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Commit 7cd5f664 authored by Davis King's avatar Davis King
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Added a copy of libjpeg so that it can be statically compiled in when 

cmake can't find a copy to dynamically link to.  This is especially
useful on windows where cmake never finds libjpeg.
parent 481c85b2
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dlib/CMakeLists.txt
View file @ 7cd5f664
......@@ -83,10 +83,9 @@ if (NOT TARGET dlib)
option(DLIB_LINK_WITH_FFTW ${DLIB_LINK_WITH_FFTW_STR} ON)
add_library(dlib STATIC all/source.cpp )
if (NOT DLIB_ISO_CPP_ONLY)
if (DLIB_ISO_CPP_ONLY)
add_library(dlib STATIC all/source.cpp )
else()
# we want to link to the right stuff depending on our platform.
if (WIN32 AND NOT CYGWIN) ###############################################################################
if (DLIB_NO_GUI_SUPPORT)
......@@ -154,6 +153,7 @@ if (NOT TARGET dlib)
endif () ##################################################################################
set(source_files all/source.cpp)
if (DLIB_LINK_WITH_LIBPNG)
# try to find libpng
......@@ -175,7 +175,35 @@ if (NOT TARGET dlib)
include_directories(${JPEG_INCLUDE_DIR})
set (dlib_needed_libraries ${dlib_needed_libraries} ${JPEG_LIBRARY})
else()
set(DLIB_LINK_WITH_LIBJPEG OFF CACHE STRING ${DLIB_LINK_WITH_LIBJPEG_STR} FORCE )
# If we can't find libjpeg then statically compile it in.
include_directories("external/libjpeg")
set(source_files ${source_files}
external/libjpeg/jcomapi.cpp
external/libjpeg/jdapimin.cpp
external/libjpeg/jdapistd.cpp
external/libjpeg/jdatasrc.cpp
external/libjpeg/jdcoefct.cpp
external/libjpeg/jdcolor.cpp
external/libjpeg/jddctmgr.cpp
external/libjpeg/jdhuff.cpp
external/libjpeg/jdinput.cpp
external/libjpeg/jdmainct.cpp
external/libjpeg/jdmarker.cpp
external/libjpeg/jdmaster.cpp
external/libjpeg/jdmerge.cpp
external/libjpeg/jdphuff.cpp
external/libjpeg/jdpostct.cpp
external/libjpeg/jdsample.cpp
external/libjpeg/jerror.cpp
external/libjpeg/jidctflt.cpp
external/libjpeg/jidctfst.cpp
external/libjpeg/jidctint.cpp
external/libjpeg/jidctred.cpp
external/libjpeg/jmemmgr.cpp
external/libjpeg/jmemnobs.cpp
external/libjpeg/jquant1.cpp
external/libjpeg/jquant2.cpp
external/libjpeg/jutils.cpp )
endif()
endif()
......@@ -234,6 +262,7 @@ if (NOT TARGET dlib)
endif()
add_library(dlib STATIC ${source_files} )
target_link_libraries(dlib ${dlib_needed_libraries} )
endif () ##### end of if NOT DLIB_ISO_CPP_ONLY ##########################################################
......
dlib/external/libjpeg/README 0 → 100644
View file @ 7cd5f664
The Independent JPEG Group's JPEG software
==========================================
README for release 6b of 27-Mar-1998
====================================
This distribution contains the sixth public release of the Independent JPEG
Group's free JPEG software. You are welcome to redistribute this software and
to use it for any purpose, subject to the conditions under LEGAL ISSUES, below.
Serious users of this software (particularly those incorporating it into
larger programs) should contact IJG at jpeg-info@uunet.uu.net to be added to
our electronic mailing list. Mailing list members are notified of updates
and have a chance to participate in technical discussions, etc.
This software is the work of Tom Lane, Philip Gladstone, Jim Boucher,
Lee Crocker, Julian Minguillon, Luis Ortiz, George Phillips, Davide Rossi,
Guido Vollbeding, Ge' Weijers, and other members of the Independent JPEG
Group.
IJG is not affiliated with the official ISO JPEG standards committee.
DOCUMENTATION ROADMAP
=====================
This file contains the following sections:
OVERVIEW General description of JPEG and the IJG software.
LEGAL ISSUES Copyright, lack of warranty, terms of distribution.
REFERENCES Where to learn more about JPEG.
ARCHIVE LOCATIONS Where to find newer versions of this software.
RELATED SOFTWARE Other stuff you should get.
FILE FORMAT WARS Software *not* to get.
TO DO Plans for future IJG releases.
Other documentation files in the distribution are:
User documentation:
install.doc How to configure and install the IJG software.
usage.doc Usage instructions for cjpeg, djpeg, jpegtran,
rdjpgcom, and wrjpgcom.
*.1 Unix-style man pages for programs (same info as usage.doc).
wizard.doc Advanced usage instructions for JPEG wizards only.
change.log Version-to-version change highlights.
Programmer and internal documentation:
libjpeg.doc How to use the JPEG library in your own programs.
example.c Sample code for calling the JPEG library.
structure.doc Overview of the JPEG library's internal structure.
filelist.doc Road map of IJG files.
coderules.doc Coding style rules --- please read if you contribute code.
Please read at least the files install.doc and usage.doc. Useful information
can also be found in the JPEG FAQ (Frequently Asked Questions) article. See
ARCHIVE LOCATIONS below to find out where to obtain the FAQ article.
If you want to understand how the JPEG code works, we suggest reading one or
more of the REFERENCES, then looking at the documentation files (in roughly
the order listed) before diving into the code.
OVERVIEW
========
This package contains C software to implement JPEG image compression and
decompression. JPEG (pronounced "jay-peg") is a standardized compression
method for full-color and gray-scale images. JPEG is intended for compressing
"real-world" scenes; line drawings, cartoons and other non-realistic images
are not its strong suit. JPEG is lossy, meaning that the output image is not
exactly identical to the input image. Hence you must not use JPEG if you
have to have identical output bits. However, on typical photographic images,
very good compression levels can be obtained with no visible change, and
remarkably high compression levels are possible if you can tolerate a
low-quality image. For more details, see the references, or just experiment
with various compression settings.
This software implements JPEG baseline, extended-sequential, and progressive
compression processes. Provision is made for supporting all variants of these
processes, although some uncommon parameter settings aren't implemented yet.
For legal reasons, we are not distributing code for the arithmetic-coding
variants of JPEG; see LEGAL ISSUES. We have made no provision for supporting
the hierarchical or lossless processes defined in the standard.
We provide a set of library routines for reading and writing JPEG image files,
plus two sample applications "cjpeg" and "djpeg", which use the library to
perform conversion between JPEG and some other popular image file formats.
The library is intended to be reused in other applications.
In order to support file conversion and viewing software, we have included
considerable functionality beyond the bare JPEG coding/decoding capability;
for example, the color quantization modules are not strictly part of JPEG
decoding, but they are essential for output to colormapped file formats or
colormapped displays. These extra functions can be compiled out of the
library if not required for a particular application. We have also included
"jpegtran", a utility for lossless transcoding between different JPEG
processes, and "rdjpgcom" and "wrjpgcom", two simple applications for
inserting and extracting textual comments in JFIF files.
The emphasis in designing this software has been on achieving portability and
flexibility, while also making it fast enough to be useful. In particular,
the software is not intended to be read as a tutorial on JPEG. (See the
REFERENCES section for introductory material.) Rather, it is intended to
be reliable, portable, industrial-strength code. We do not claim to have
achieved that goal in every aspect of the software, but we strive for it.
We welcome the use of this software as a component of commercial products.
No royalty is required, but we do ask for an acknowledgement in product
documentation, as described under LEGAL ISSUES.
LEGAL ISSUES
============
In plain English:
1. We don't promise that this software works. (But if you find any bugs,
please let us know!)
2. You can use this software for whatever you want. You don't have to pay us.
3. You may not pretend that you wrote this software. If you use it in a
program, you must acknowledge somewhere in your documentation that
you've used the IJG code.
In legalese:
The authors make NO WARRANTY or representation, either express or implied,
with respect to this software, its quality, accuracy, merchantability, or
fitness for a particular purpose. This software is provided "AS IS", and you,
its user, assume the entire risk as to its quality and accuracy.
This software is copyright (C) 1991-1998, Thomas G. Lane.
All Rights Reserved except as specified below.
Permission is hereby granted to use, copy, modify, and distribute this
software (or portions thereof) for any purpose, without fee, subject to these
conditions:
(1) If any part of the source code for this software is distributed, then this
README file must be included, with this copyright and no-warranty notice
unaltered; and any additions, deletions, or changes to the original files
must be clearly indicated in accompanying documentation.
(2) If only executable code is distributed, then the accompanying
documentation must state that "this software is based in part on the work of
the Independent JPEG Group".
(3) Permission for use of this software is granted only if the user accepts
full responsibility for any undesirable consequences; the authors accept
NO LIABILITY for damages of any kind.
These conditions apply to any software derived from or based on the IJG code,
not just to the unmodified library. If you use our work, you ought to
acknowledge us.
Permission is NOT granted for the use of any IJG author's name or company name
in advertising or publicity relating to this software or products derived from
it. This software may be referred to only as "the Independent JPEG Group's
software".
We specifically permit and encourage the use of this software as the basis of
commercial products, provided that all warranty or liability claims are
assumed by the product vendor.
ansi2knr.c is included in this distribution by permission of L. Peter Deutsch,
sole proprietor of its copyright holder, Aladdin Enterprises of Menlo Park, CA.
ansi2knr.c is NOT covered by the above copyright and conditions, but instead
by the usual distribution terms of the Free Software Foundation; principally,
that you must include source code if you redistribute it. (See the file
ansi2knr.c for full details.) However, since ansi2knr.c is not needed as part
of any program generated from the IJG code, this does not limit you more than
the foregoing paragraphs do.
The Unix configuration script "configure" was produced with GNU Autoconf.
It is copyright by the Free Software Foundation but is freely distributable.
The same holds for its supporting scripts (config.guess, config.sub,
ltconfig, ltmain.sh). Another support script, install-sh, is copyright
by M.I.T. but is also freely distributable.
It appears that the arithmetic coding option of the JPEG spec is covered by
patents owned by IBM, AT&T, and Mitsubishi. Hence arithmetic coding cannot
legally be used without obtaining one or more licenses. For this reason,
support for arithmetic coding has been removed from the free JPEG software.
(Since arithmetic coding provides only a marginal gain over the unpatented
Huffman mode, it is unlikely that very many implementations will support it.)
So far as we are aware, there are no patent restrictions on the remaining
code.
The IJG distribution formerly included code to read and write GIF files.
To avoid entanglement with the Unisys LZW patent, GIF reading support has
been removed altogether, and the GIF writer has been simplified to produce
"uncompressed GIFs". This technique does not use the LZW algorithm; the
resulting GIF files are larger than usual, but are readable by all standard
GIF decoders.
We are required to state that
"The Graphics Interchange Format(c) is the Copyright property of
CompuServe Incorporated. GIF(sm) is a Service Mark property of
CompuServe Incorporated."
REFERENCES
==========
We highly recommend reading one or more of these references before trying to
understand the innards of the JPEG software.
The best short technical introduction to the JPEG compression algorithm is
Wallace, Gregory K. "The JPEG Still Picture Compression Standard",
Communications of the ACM, April 1991 (vol. 34 no. 4), pp. 30-44.
(Adjacent articles in that issue discuss MPEG motion picture compression,
applications of JPEG, and related topics.) If you don't have the CACM issue
handy, a PostScript file containing a revised version of Wallace's article is
available at ftp://ftp.uu.net/graphics/jpeg/wallace.ps.gz. The file (actually
a preprint for an article that appeared in IEEE Trans. Consumer Electronics)
omits the sample images that appeared in CACM, but it includes corrections
and some added material. Note: the Wallace article is copyright ACM and IEEE,
and it may not be used for commercial purposes.
A somewhat less technical, more leisurely introduction to JPEG can be found in
"The Data Compression Book" by Mark Nelson and Jean-loup Gailly, published by
M&T Books (New York), 2nd ed. 1996, ISBN 1-55851-434-1. This book provides
good explanations and example C code for a multitude of compression methods
including JPEG. It is an excellent source if you are comfortable reading C
code but don't know much about data compression in general. The book's JPEG
sample code is far from industrial-strength, but when you are ready to look
at a full implementation, you've got one here...
The best full description of JPEG is the textbook "JPEG Still Image Data
Compression Standard" by William B. Pennebaker and Joan L. Mitchell, published
by Van Nostrand Reinhold, 1993, ISBN 0-442-01272-1. Price US$59.95, 638 pp.
The book includes the complete text of the ISO JPEG standards (DIS 10918-1
and draft DIS 10918-2). This is by far the most complete exposition of JPEG
in existence, and we highly recommend it.
The JPEG standard itself is not available electronically; you must order a
paper copy through ISO or ITU. (Unless you feel a need to own a certified
official copy, we recommend buying the Pennebaker and Mitchell book instead;
it's much cheaper and includes a great deal of useful explanatory material.)
In the USA, copies of the standard may be ordered from ANSI Sales at (212)
642-4900, or from Global Engineering Documents at (800) 854-7179. (ANSI
doesn't take credit card orders, but Global does.) It's not cheap: as of
1992, ANSI was charging $95 for Part 1 and $47 for Part 2, plus 7%
shipping/handling. The standard is divided into two parts, Part 1 being the
actual specification, while Part 2 covers compliance testing methods. Part 1
is titled "Digital Compression and Coding of Continuous-tone Still Images,
Part 1: Requirements and guidelines" and has document numbers ISO/IEC IS
10918-1, ITU-T T.81. Part 2 is titled "Digital Compression and Coding of
Continuous-tone Still Images, Part 2: Compliance testing" and has document
numbers ISO/IEC IS 10918-2, ITU-T T.83.
Some extensions to the original JPEG standard are defined in JPEG Part 3,
a newer ISO standard numbered ISO/IEC IS 10918-3 and ITU-T T.84. IJG
currently does not support any Part 3 extensions.
The JPEG standard does not specify all details of an interchangeable file
format. For the omitted details we follow the "JFIF" conventions, revision
1.02. A copy of the JFIF spec is available from:
Literature Department
C-Cube Microsystems, Inc.
1778 McCarthy Blvd.
Milpitas, CA 95035
phone (408) 944-6300, fax (408) 944-6314
A PostScript version of this document is available by FTP at
ftp://ftp.uu.net/graphics/jpeg/jfif.ps.gz. There is also a plain text
version at ftp://ftp.uu.net/graphics/jpeg/jfif.txt.gz, but it is missing
the figures.
The TIFF 6.0 file format specification can be obtained by FTP from
ftp://ftp.sgi.com/graphics/tiff/TIFF6.ps.gz. The JPEG incorporation scheme
found in the TIFF 6.0 spec of 3-June-92 has a number of serious problems.
IJG does not recommend use of the TIFF 6.0 design (TIFF Compression tag 6).
Instead, we recommend the JPEG design proposed by TIFF Technical Note #2
(Compression tag 7). Copies of this Note can be obtained from ftp.sgi.com or
from ftp://ftp.uu.net/graphics/jpeg/. It is expected that the next revision
of the TIFF spec will replace the 6.0 JPEG design with the Note's design.
Although IJG's own code does not support TIFF/JPEG, the free libtiff library
uses our library to implement TIFF/JPEG per the Note. libtiff is available
from ftp://ftp.sgi.com/graphics/tiff/.
ARCHIVE LOCATIONS
=================
The "official" archive site for this software is ftp.uu.net (Internet
address 192.48.96.9). The most recent released version can always be found
there in directory graphics/jpeg. This particular version will be archived
as ftp://ftp.uu.net/graphics/jpeg/jpegsrc.v6b.tar.gz. If you don't have
direct Internet access, UUNET's archives are also available via UUCP; contact
help@uunet.uu.net for information on retrieving files that way.
Numerous Internet sites maintain copies of the UUNET files. However, only
ftp.uu.net is guaranteed to have the latest official version.
You can also obtain this software in DOS-compatible "zip" archive format from
the SimTel archives (ftp://ftp.simtel.net/pub/simtelnet/msdos/graphics/), or
on CompuServe in the Graphics Support forum (GO CIS:GRAPHSUP), library 12
"JPEG Tools". Again, these versions may sometimes lag behind the ftp.uu.net
release.
The JPEG FAQ (Frequently Asked Questions) article is a useful source of
general information about JPEG. It is updated constantly and therefore is
not included in this distribution. The FAQ is posted every two weeks to
Usenet newsgroups comp.graphics.misc, news.answers, and other groups.
It is available on the World Wide Web at http://www.faqs.org/faqs/jpeg-faq/
and other news.answers archive sites, including the official news.answers
archive at rtfm.mit.edu: ftp://rtfm.mit.edu/pub/usenet/news.answers/jpeg-faq/.
If you don't have Web or FTP access, send e-mail to mail-server@rtfm.mit.edu
with body
send usenet/news.answers/jpeg-faq/part1
send usenet/news.answers/jpeg-faq/part2
RELATED SOFTWARE
================
Numerous viewing and image manipulation programs now support JPEG. (Quite a
few of them use this library to do so.) The JPEG FAQ described above lists
some of the more popular free and shareware viewers, and tells where to
obtain them on Internet.
If you are on a Unix machine, we highly recommend Jef Poskanzer's free
PBMPLUS software, which provides many useful operations on PPM-format image
files. In particular, it can convert PPM images to and from a wide range of
other formats, thus making cjpeg/djpeg considerably more useful. The latest
version is distributed by the NetPBM group, and is available from numerous
sites, notably ftp://wuarchive.wustl.edu/graphics/graphics/packages/NetPBM/.
Unfortunately PBMPLUS/NETPBM is not nearly as portable as the IJG software is;
you are likely to have difficulty making it work on any non-Unix machine.
A different free JPEG implementation, written by the PVRG group at Stanford,
is available from ftp://havefun.stanford.edu/pub/jpeg/. This program
is designed for research and experimentation rather than production use;
it is slower, harder to use, and less portable than the IJG code, but it
is easier to read and modify. Also, the PVRG code supports lossless JPEG,
which we do not. (On the other hand, it doesn't do progressive JPEG.)
FILE FORMAT WARS
================
Some JPEG programs produce files that are not compatible with our library.
The root of the problem is that the ISO JPEG committee failed to specify a
concrete file format. Some vendors "filled in the blanks" on their own,
creating proprietary formats that no one else could read. (For example, none
of the early commercial JPEG implementations for the Macintosh were able to
exchange compressed files.)
The file format we have adopted is called JFIF (see REFERENCES). This format
has been agreed to by a number of major commercial JPEG vendors, and it has
become the de facto standard. JFIF is a minimal or "low end" representation.
We recommend the use of TIFF/JPEG (TIFF revision 6.0 as modified by TIFF
Technical Note #2) for "high end" applications that need to record a lot of
additional data about an image. TIFF/JPEG is fairly new and not yet widely
supported, unfortunately.
The upcoming JPEG Part 3 standard defines a file format called SPIFF.
SPIFF is interoperable with JFIF, in the sense that most JFIF decoders should
be able to read the most common variant of SPIFF. SPIFF has some technical
advantages over JFIF, but its major claim to fame is simply that it is an
official standard rather than an informal one. At this point it is unclear
whether SPIFF will supersede JFIF or whether JFIF will remain the de-facto
standard. IJG intends to support SPIFF once the standard is frozen, but we
have not decided whether it should become our default output format or not.
(In any case, our decoder will remain capable of reading JFIF indefinitely.)
Various proprietary file formats incorporating JPEG compression also exist.
We have little or no sympathy for the existence of these formats. Indeed,
one of the original reasons for developing this free software was to help
force convergence on common, open format standards for JPEG files. Don't
use a proprietary file format!
TO DO
=====
The major thrust for v7 will probably be improvement of visual quality.
The current method for scaling the quantization tables is known not to be
very good at low Q values. We also intend to investigate block boundary
smoothing, "poor man's variable quantization", and other means of improving
quality-vs-file-size performance without sacrificing compatibility.
In future versions, we are considering supporting some of the upcoming JPEG
Part 3 extensions --- principally, variable quantization and the SPIFF file
format.
As always, speeding things up is of great interest.
Please send bug reports, offers of help, etc. to jpeg-info@uunet.uu.net.
dlib/external/libjpeg/jcomapi.cpp 0 → 100644
View file @ 7cd5f664
/*
* jcomapi.c
*
* Copyright (C) 1994-1997, Thomas G. Lane.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file contains application interface routines that are used for both
* compression and decompression.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
/*
* Abort processing of a JPEG compression or decompression operation,
* but don't destroy the object itself.
*
* For this, we merely clean up all the nonpermanent memory pools.
* Note that temp files (virtual arrays) are not allowed to belong to
* the permanent pool, so we will be able to close all temp files here.
* Closing a data source or destination, if necessary, is the application's
* responsibility.
*/
GLOBAL(void)
jpeg_abort (j_common_ptr cinfo)
{
int pool;
/* Do nothing if called on a not-initialized or destroyed JPEG object. */
if (cinfo->mem == NULL)
return;
/* Releasing pools in reverse order might help avoid fragmentation
* with some (brain-damaged) malloc libraries.
*/
for (pool = JPOOL_NUMPOOLS-1; pool > JPOOL_PERMANENT; pool--) {
(*cinfo->mem->free_pool) (cinfo, pool);
}
/* Reset overall state for possible reuse of object */
if (cinfo->is_decompressor) {
cinfo->global_state = DSTATE_START;
/* Try to keep application from accessing now-deleted marker list.
* A bit kludgy to do it here, but this is the most central place.
*/
((j_decompress_ptr) cinfo)->marker_list = NULL;
} else {
cinfo->global_state = CSTATE_START;
}
}
/*
* Destruction of a JPEG object.
*
* Everything gets deallocated except the master jpeg_compress_struct itself
* and the error manager struct. Both of these are supplied by the application
* and must be freed, if necessary, by the application. (Often they are on
* the stack and so don't need to be freed anyway.)
* Closing a data source or destination, if necessary, is the application's
* responsibility.
*/
GLOBAL(void)
jpeg_destroy (j_common_ptr cinfo)
{
/* We need only tell the memory manager to release everything. */
/* NB: mem pointer is NULL if memory mgr failed to initialize. */
if (cinfo->mem != NULL)
(*cinfo->mem->self_destruct) (cinfo);
cinfo->mem = NULL; /* be safe if jpeg_destroy is called twice */
cinfo->global_state = 0; /* mark it destroyed */
}
/*
* Convenience routines for allocating quantization and Huffman tables.
* (Would jutils.c be a more reasonable place to put these?)
*/
GLOBAL(JQUANT_TBL *)
jpeg_alloc_quant_table (j_common_ptr cinfo)
{
JQUANT_TBL *tbl;
tbl = (JQUANT_TBL *)
(*cinfo->mem->alloc_small) (cinfo, JPOOL_PERMANENT, SIZEOF(JQUANT_TBL));
tbl->sent_table = FALSE; /* make sure this is false in any new table */
return tbl;
}
GLOBAL(JHUFF_TBL *)
jpeg_alloc_huff_table (j_common_ptr cinfo)
{
JHUFF_TBL *tbl;
tbl = (JHUFF_TBL *)
(*cinfo->mem->alloc_small) (cinfo, JPOOL_PERMANENT, SIZEOF(JHUFF_TBL));
tbl->sent_table = FALSE; /* make sure this is false in any new table */
return tbl;
}
dlib/external/libjpeg/jconfig.h 0 → 100644
View file @ 7cd5f664
/* jconfig.h. Generated automatically by configure. */
/* jconfig.cfg --- source file edited by configure script */
/* see jconfig.doc for explanations */
#define HAVE_PROTOTYPES
#define HAVE_UNSIGNED_CHAR
#define HAVE_UNSIGNED_SHORT
#undef void
#undef const
#undef CHAR_IS_UNSIGNED
#define HAVE_STDDEF_H
#define HAVE_STDLIB_H
#undef NEED_BSD_STRINGS
#undef NEED_SYS_TYPES_H
#undef NEED_FAR_POINTERS
#undef NEED_SHORT_EXTERNAL_NAMES
/* Define this if you get warnings about undefined structures. */
#undef INCOMPLETE_TYPES_BROKEN
#ifdef JPEG_INTERNALS
#undef RIGHT_SHIFT_IS_UNSIGNED
#define INLINE __inline__
/* These are for configuring the JPEG memory manager. */
#undef DEFAULT_MAX_MEM
#undef NO_MKTEMP
#endif /* JPEG_INTERNALS */
#ifdef JPEG_CJPEG_DJPEG
#define BMP_SUPPORTED /* BMP image file format */
#define GIF_SUPPORTED /* GIF image file format */
#define PPM_SUPPORTED /* PBMPLUS PPM/PGM image file format */
#undef RLE_SUPPORTED /* Utah RLE image file format */
#define TARGA_SUPPORTED /* Targa image file format */
#undef TWO_FILE_COMMANDLINE
#undef NEED_SIGNAL_CATCHER
#undef DONT_USE_B_MODE
/* Define this if you want percent-done progress reports from cjpeg/djpeg. */
#undef PROGRESS_REPORT
#endif /* JPEG_CJPEG_DJPEG */
dlib/external/libjpeg/jdapimin.cpp 0 → 100644
View file @ 7cd5f664
/*
* jdapimin.c
*
* Copyright (C) 1994-1998, Thomas G. Lane.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file contains application interface code for the decompression half
* of the JPEG library. These are the "minimum" API routines that may be
* needed in either the normal full-decompression case or the
* transcoding-only case.
*
* Most of the routines intended to be called directly by an application
* are in this file or in jdapistd.c. But also see jcomapi.c for routines
* shared by compression and decompression, and jdtrans.c for the transcoding
* case.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
/*
* Initialization of a JPEG decompression object.
* The error manager must already be set up (in case memory manager fails).
*/
GLOBAL(void)
jpeg_CreateDecompress (j_decompress_ptr cinfo, int version, size_t structsize)
{
int i;
/* Guard against version mismatches between library and caller. */
cinfo->mem = NULL; /* so jpeg_destroy knows mem mgr not called */
if (version != JPEG_LIB_VERSION)
ERREXIT2(cinfo, JERR_BAD_LIB_VERSION, JPEG_LIB_VERSION, version);
if (structsize != SIZEOF(struct jpeg_decompress_struct))
ERREXIT2(cinfo, JERR_BAD_STRUCT_SIZE,
(int) SIZEOF(struct jpeg_decompress_struct), (int) structsize);
/* For debugging purposes, we zero the whole master structure.
* But the application has already set the err pointer, and may have set
* client_data, so we have to save and restore those fields.
* Note: if application hasn't set client_data, tools like Purify may
* complain here.
*/
{
struct jpeg_error_mgr * err = cinfo->err;
void * client_data = cinfo->client_data; /* ignore Purify complaint here */
MEMZERO(cinfo, SIZEOF(struct jpeg_decompress_struct));
cinfo->err = err;
cinfo->client_data = client_data;
}
cinfo->is_decompressor = TRUE;
/* Initialize a memory manager instance for this object */
jinit_memory_mgr((j_common_ptr) cinfo);
/* Zero out pointers to permanent structures. */
cinfo->progress = NULL;
cinfo->src = NULL;
for (i = 0; i < NUM_QUANT_TBLS; i++)
cinfo->quant_tbl_ptrs[i] = NULL;
for (i = 0; i < NUM_HUFF_TBLS; i++) {
cinfo->dc_huff_tbl_ptrs[i] = NULL;
cinfo->ac_huff_tbl_ptrs[i] = NULL;
}
/* Initialize marker processor so application can override methods
* for COM, APPn markers before calling jpeg_read_header.
*/
cinfo->marker_list = NULL;
jinit_marker_reader(cinfo);
/* And initialize the overall input controller. */
jinit_input_controller(cinfo);
/* OK, I'm ready */
cinfo->global_state = DSTATE_START;
}
/*
* Destruction of a JPEG decompression object
*/
GLOBAL(void)
jpeg_destroy_decompress (j_decompress_ptr cinfo)
{
jpeg_destroy((j_common_ptr) cinfo); /* use common routine */
}
/*
* Abort processing of a JPEG decompression operation,
* but don't destroy the object itself.
*/
GLOBAL(void)
jpeg_abort_decompress (j_decompress_ptr cinfo)
{
jpeg_abort((j_common_ptr) cinfo); /* use common routine */
}
/*
* Set default decompression parameters.
*/
LOCAL(void)
default_decompress_parms (j_decompress_ptr cinfo)
{
/* Guess the input colorspace, and set output colorspace accordingly. */
/* (Wish JPEG committee had provided a real way to specify this...) */
/* Note application may override our guesses. */
switch (cinfo->num_components) {
case 1:
cinfo->jpeg_color_space = JCS_GRAYSCALE;
cinfo->out_color_space = JCS_GRAYSCALE;
break;
case 3:
if (cinfo->saw_JFIF_marker) {
cinfo->jpeg_color_space = JCS_YCbCr; /* JFIF implies YCbCr */
} else if (cinfo->saw_Adobe_marker) {
switch (cinfo->Adobe_transform) {
case 0:
cinfo->jpeg_color_space = JCS_RGB;
break;
case 1:
cinfo->jpeg_color_space = JCS_YCbCr;
break;
default:
WARNMS1(cinfo, JWRN_ADOBE_XFORM, cinfo->Adobe_transform);
cinfo->jpeg_color_space = JCS_YCbCr; /* assume it's YCbCr */
break;
}
} else {
/* Saw no special markers, try to guess from the component IDs */
int cid0 = cinfo->comp_info[0].component_id;
int cid1 = cinfo->comp_info[1].component_id;
int cid2 = cinfo->comp_info[2].component_id;
if (cid0 == 1 && cid1 == 2 && cid2 == 3)
cinfo->jpeg_color_space = JCS_YCbCr; /* assume JFIF w/out marker */
else if (cid0 == 82 && cid1 == 71 && cid2 == 66)
cinfo->jpeg_color_space = JCS_RGB; /* ASCII 'R', 'G', 'B' */
else {
TRACEMS3(cinfo, 1, JTRC_UNKNOWN_IDS, cid0, cid1, cid2);
cinfo->jpeg_color_space = JCS_YCbCr; /* assume it's YCbCr */
}
}
/* Always guess RGB is proper output colorspace. */
cinfo->out_color_space = JCS_RGB;
break;
case 4:
if (cinfo->saw_Adobe_marker) {
switch (cinfo->Adobe_transform) {
case 0:
cinfo->jpeg_color_space = JCS_CMYK;
break;
case 2:
cinfo->jpeg_color_space = JCS_YCCK;
break;
default:
WARNMS1(cinfo, JWRN_ADOBE_XFORM, cinfo->Adobe_transform);
cinfo->jpeg_color_space = JCS_YCCK; /* assume it's YCCK */
break;
}
} else {
/* No special markers, assume straight CMYK. */
cinfo->jpeg_color_space = JCS_CMYK;
}
cinfo->out_color_space = JCS_CMYK;
break;
default:
cinfo->jpeg_color_space = JCS_UNKNOWN;
cinfo->out_color_space = JCS_UNKNOWN;
break;
}
/* Set defaults for other decompression parameters. */
cinfo->scale_num = 1; /* 1:1 scaling */
cinfo->scale_denom = 1;
cinfo->output_gamma = 1.0;
cinfo->buffered_image = FALSE;
cinfo->raw_data_out = FALSE;
cinfo->dct_method = JDCT_DEFAULT;
cinfo->do_fancy_upsampling = TRUE;
cinfo->do_block_smoothing = TRUE;
cinfo->quantize_colors = FALSE;
/* We set these in case application only sets quantize_colors. */
cinfo->dither_mode = JDITHER_FS;
#ifdef QUANT_2PASS_SUPPORTED
cinfo->two_pass_quantize = TRUE;
#else
cinfo->two_pass_quantize = FALSE;
#endif
cinfo->desired_number_of_colors = 256;
cinfo->colormap = NULL;
/* Initialize for no mode change in buffered-image mode. */
cinfo->enable_1pass_quant = FALSE;
cinfo->enable_external_quant = FALSE;
cinfo->enable_2pass_quant = FALSE;
}
/*
* Decompression startup: read start of JPEG datastream to see what's there.
* Need only initialize JPEG object and supply a data source before calling.
*
* This routine will read as far as the first SOS marker (ie, actual start of
* compressed data), and will save all tables and parameters in the JPEG
* object. It will also initialize the decompression parameters to default
* values, and finally return JPEG_HEADER_OK. On return, the application may
* adjust the decompression parameters and then call jpeg_start_decompress.
* (Or, if the application only wanted to determine the image parameters,
* the data need not be decompressed. In that case, call jpeg_abort or
* jpeg_destroy to release any temporary space.)
* If an abbreviated (tables only) datastream is presented, the routine will
* return JPEG_HEADER_TABLES_ONLY upon reaching EOI. The application may then
* re-use the JPEG object to read the abbreviated image datastream(s).
* It is unnecessary (but OK) to call jpeg_abort in this case.
* The JPEG_SUSPENDED return code only occurs if the data source module
* requests suspension of the decompressor. In this case the application
* should load more source data and then re-call jpeg_read_header to resume
* processing.
* If a non-suspending data source is used and require_image is TRUE, then the
* return code need not be inspected since only JPEG_HEADER_OK is possible.
*
* This routine is now just a front end to jpeg_consume_input, with some
* extra error checking.
*/
GLOBAL(int)
jpeg_read_header (j_decompress_ptr cinfo, boolean require_image)
{
int retcode;
if (cinfo->global_state != DSTATE_START &&
cinfo->global_state != DSTATE_INHEADER)
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
retcode = jpeg_consume_input(cinfo);
switch (retcode) {
case JPEG_REACHED_SOS:
retcode = JPEG_HEADER_OK;
break;
case JPEG_REACHED_EOI:
if (require_image) /* Complain if application wanted an image */
ERREXIT(cinfo, JERR_NO_IMAGE);
/* Reset to start state; it would be safer to require the application to
* call jpeg_abort, but we can't change it now for compatibility reasons.
* A side effect is to free any temporary memory (there shouldn't be any).
*/
jpeg_abort((j_common_ptr) cinfo); /* sets state = DSTATE_START */
retcode = JPEG_HEADER_TABLES_ONLY;
break;
case JPEG_SUSPENDED:
/* no work */
break;
}
return retcode;
}
/*
* Consume data in advance of what the decompressor requires.
* This can be called at any time once the decompressor object has
* been created and a data source has been set up.
*
* This routine is essentially a state machine that handles a couple
* of critical state-transition actions, namely initial setup and
* transition from header scanning to ready-for-start_decompress.
* All the actual input is done via the input controller's consume_input
* method.
*/
GLOBAL(int)
jpeg_consume_input (j_decompress_ptr cinfo)
{
int retcode = JPEG_SUSPENDED;
/* NB: every possible DSTATE value should be listed in this switch */
switch (cinfo->global_state) {
case DSTATE_START:
/* Start-of-datastream actions: reset appropriate modules */
(*cinfo->inputctl->reset_input_controller) (cinfo);
/* Initialize application's data source module */
(*cinfo->src->init_source) (cinfo);
cinfo->global_state = DSTATE_INHEADER;
/*FALLTHROUGH*/
case DSTATE_INHEADER:
retcode = (*cinfo->inputctl->consume_input) (cinfo);
if (retcode == JPEG_REACHED_SOS) { /* Found SOS, prepare to decompress */
/* Set up default parameters based on header data */
default_decompress_parms(cinfo);
/* Set global state: ready for start_decompress */
cinfo->global_state = DSTATE_READY;
}
break;
case DSTATE_READY:
/* Can't advance past first SOS until start_decompress is called */
retcode = JPEG_REACHED_SOS;
break;
case DSTATE_PRELOAD:
case DSTATE_PRESCAN:
case DSTATE_SCANNING:
case DSTATE_RAW_OK:
case DSTATE_BUFIMAGE:
case DSTATE_BUFPOST:
case DSTATE_STOPPING:
retcode = (*cinfo->inputctl->consume_input) (cinfo);
break;
default:
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
}
return retcode;
}
/*
* Have we finished reading the input file?
*/
GLOBAL(boolean)
jpeg_input_complete (j_decompress_ptr cinfo)
{
/* Check for valid jpeg object */
if (cinfo->global_state < DSTATE_START ||
cinfo->global_state > DSTATE_STOPPING)
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
return cinfo->inputctl->eoi_reached;
}
/*
* Is there more than one scan?
*/
GLOBAL(boolean)
jpeg_has_multiple_scans (j_decompress_ptr cinfo)
{
/* Only valid after jpeg_read_header completes */
if (cinfo->global_state < DSTATE_READY ||
cinfo->global_state > DSTATE_STOPPING)
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
return cinfo->inputctl->has_multiple_scans;
}
/*
* Finish JPEG decompression.
*
* This will normally just verify the file trailer and release temp storage.
*
* Returns FALSE if suspended. The return value need be inspected only if
* a suspending data source is used.
*/
GLOBAL(boolean)
jpeg_finish_decompress (j_decompress_ptr cinfo)
{
if ((cinfo->global_state == DSTATE_SCANNING ||
cinfo->global_state == DSTATE_RAW_OK) && ! cinfo->buffered_image) {
/* Terminate final pass of non-buffered mode */
if (cinfo->output_scanline < cinfo->output_height)
ERREXIT(cinfo, JERR_TOO_LITTLE_DATA);
(*cinfo->master->finish_output_pass) (cinfo);
cinfo->global_state = DSTATE_STOPPING;
} else if (cinfo->global_state == DSTATE_BUFIMAGE) {
/* Finishing after a buffered-image operation */
cinfo->global_state = DSTATE_STOPPING;
} else if (cinfo->global_state != DSTATE_STOPPING) {
/* STOPPING = repeat call after a suspension, anything else is error */
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
}
/* Read until EOI */
while (! cinfo->inputctl->eoi_reached) {
if ((*cinfo->inputctl->consume_input) (cinfo) == JPEG_SUSPENDED)
return FALSE; /* Suspend, come back later */
}
/* Do final cleanup */
(*cinfo->src->term_source) (cinfo);
/* We can use jpeg_abort to release memory and reset global_state */
jpeg_abort((j_common_ptr) cinfo);
return TRUE;
}
dlib/external/libjpeg/jdapistd.cpp 0 → 100644
View file @ 7cd5f664
/*
* jdapistd.c
*
* Copyright (C) 1994-1996, Thomas G. Lane.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file contains application interface code for the decompression half
* of the JPEG library. These are the "standard" API routines that are
* used in the normal full-decompression case. They are not used by a
* transcoding-only application. Note that if an application links in
* jpeg_start_decompress, it will end up linking in the entire decompressor.
* We thus must separate this file from jdapimin.c to avoid linking the
* whole decompression library into a transcoder.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
/* Forward declarations */
LOCAL(boolean) output_pass_setup JPP((j_decompress_ptr cinfo));
/*
* Decompression initialization.
* jpeg_read_header must be completed before calling this.
*
* If a multipass operating mode was selected, this will do all but the
* last pass, and thus may take a great deal of time.
*
* Returns FALSE if suspended. The return value need be inspected only if
* a suspending data source is used.
*/
GLOBAL(boolean)
jpeg_start_decompress (j_decompress_ptr cinfo)
{
if (cinfo->global_state == DSTATE_READY) {
/* First call: initialize master control, select active modules */
jinit_master_decompress(cinfo);
if (cinfo->buffered_image) {
/* No more work here; expecting jpeg_start_output next */
cinfo->global_state = DSTATE_BUFIMAGE;
return TRUE;
}
cinfo->global_state = DSTATE_PRELOAD;
}
if (cinfo->global_state == DSTATE_PRELOAD) {
/* If file has multiple scans, absorb them all into the coef buffer */
if (cinfo->inputctl->has_multiple_scans) {
#ifdef D_MULTISCAN_FILES_SUPPORTED
for (;;) {
int retcode;
/* Call progress monitor hook if present */
if (cinfo->progress != NULL)
(*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);
/* Absorb some more input */
retcode = (*cinfo->inputctl->consume_input) (cinfo);
if (retcode == JPEG_SUSPENDED)
return FALSE;
if (retcode == JPEG_REACHED_EOI)
break;
/* Advance progress counter if appropriate */
if (cinfo->progress != NULL &&
(retcode == JPEG_ROW_COMPLETED || retcode == JPEG_REACHED_SOS)) {
if (++cinfo->progress->pass_counter >= cinfo->progress->pass_limit) {
/* jdmaster underestimated number of scans; ratchet up one scan */
cinfo->progress->pass_limit += (long) cinfo->total_iMCU_rows;
}
}
}
#else
ERREXIT(cinfo, JERR_NOT_COMPILED);
#endif /* D_MULTISCAN_FILES_SUPPORTED */
}
cinfo->output_scan_number = cinfo->input_scan_number;
} else if (cinfo->global_state != DSTATE_PRESCAN)
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
/* Perform any dummy output passes, and set up for the final pass */
return output_pass_setup(cinfo);
}
/*
* Set up for an output pass, and perform any dummy pass(es) needed.
* Common subroutine for jpeg_start_decompress and jpeg_start_output.
* Entry: global_state = DSTATE_PRESCAN only if previously suspended.
* Exit: If done, returns TRUE and sets global_state for proper output mode.
* If suspended, returns FALSE and sets global_state = DSTATE_PRESCAN.
*/
LOCAL(boolean)
output_pass_setup (j_decompress_ptr cinfo)
{
if (cinfo->global_state != DSTATE_PRESCAN) {
/* First call: do pass setup */
(*cinfo->master->prepare_for_output_pass) (cinfo);
cinfo->output_scanline = 0;
cinfo->global_state = DSTATE_PRESCAN;
}
/* Loop over any required dummy passes */
while (cinfo->master->is_dummy_pass) {
#ifdef QUANT_2PASS_SUPPORTED
/* Crank through the dummy pass */
while (cinfo->output_scanline < cinfo->output_height) {
JDIMENSION last_scanline;
/* Call progress monitor hook if present */
if (cinfo->progress != NULL) {
cinfo->progress->pass_counter = (long) cinfo->output_scanline;
cinfo->progress->pass_limit = (long) cinfo->output_height;
(*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);
}
/* Process some data */
last_scanline = cinfo->output_scanline;
(*cinfo->main->process_data) (cinfo, (JSAMPARRAY) NULL,
&cinfo->output_scanline, (JDIMENSION) 0);
if (cinfo->output_scanline == last_scanline)
return FALSE; /* No progress made, must suspend */
}
/* Finish up dummy pass, and set up for another one */
(*cinfo->master->finish_output_pass) (cinfo);
(*cinfo->master->prepare_for_output_pass) (cinfo);
cinfo->output_scanline = 0;
#else
ERREXIT(cinfo, JERR_NOT_COMPILED);
#endif /* QUANT_2PASS_SUPPORTED */
}
/* Ready for application to drive output pass through
* jpeg_read_scanlines or jpeg_read_raw_data.
*/
cinfo->global_state = cinfo->raw_data_out ? DSTATE_RAW_OK : DSTATE_SCANNING;
return TRUE;
}
/*
* Read some scanlines of data from the JPEG decompressor.
*
* The return value will be the number of lines actually read.
* This may be less than the number requested in several cases,
* including bottom of image, data source suspension, and operating
* modes that emit multiple scanlines at a time.
*
* Note: we warn about excess calls to jpeg_read_scanlines() since
* this likely signals an application programmer error. However,
* an oversize buffer (max_lines > scanlines remaining) is not an error.
*/
GLOBAL(JDIMENSION)
jpeg_read_scanlines (j_decompress_ptr cinfo, JSAMPARRAY scanlines,
JDIMENSION max_lines)
{
JDIMENSION row_ctr;
if (cinfo->global_state != DSTATE_SCANNING)
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
if (cinfo->output_scanline >= cinfo->output_height) {
WARNMS(cinfo, JWRN_TOO_MUCH_DATA);
return 0;
}
/* Call progress monitor hook if present */
if (cinfo->progress != NULL) {
cinfo->progress->pass_counter = (long) cinfo->output_scanline;
cinfo->progress->pass_limit = (long) cinfo->output_height;
(*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);
}
/* Process some data */
row_ctr = 0;
(*cinfo->main->process_data) (cinfo, scanlines, &row_ctr, max_lines);
cinfo->output_scanline += row_ctr;
return row_ctr;
}
/*
* Alternate entry point to read raw data.
* Processes exactly one iMCU row per call, unless suspended.
*/
GLOBAL(JDIMENSION)
jpeg_read_raw_data (j_decompress_ptr cinfo, JSAMPIMAGE data,
JDIMENSION max_lines)
{
JDIMENSION lines_per_iMCU_row;
if (cinfo->global_state != DSTATE_RAW_OK)
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
if (cinfo->output_scanline >= cinfo->output_height) {
WARNMS(cinfo, JWRN_TOO_MUCH_DATA);
return 0;
}
/* Call progress monitor hook if present */
if (cinfo->progress != NULL) {
cinfo->progress->pass_counter = (long) cinfo->output_scanline;
cinfo->progress->pass_limit = (long) cinfo->output_height;
(*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);
}
/* Verify that at least one iMCU row can be returned. */
lines_per_iMCU_row = cinfo->max_v_samp_factor * cinfo->min_DCT_scaled_size;
if (max_lines < lines_per_iMCU_row)
ERREXIT(cinfo, JERR_BUFFER_SIZE);
/* Decompress directly into user's buffer. */
if (! (*cinfo->coef->decompress_data) (cinfo, data))
return 0; /* suspension forced, can do nothing more */
/* OK, we processed one iMCU row. */
cinfo->output_scanline += lines_per_iMCU_row;
return lines_per_iMCU_row;
}
/* Additional entry points for buffered-image mode. */
#ifdef D_MULTISCAN_FILES_SUPPORTED
/*
* Initialize for an output pass in buffered-image mode.
*/
GLOBAL(boolean)
jpeg_start_output (j_decompress_ptr cinfo, int scan_number)
{
if (cinfo->global_state != DSTATE_BUFIMAGE &&
cinfo->global_state != DSTATE_PRESCAN)
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
/* Limit scan number to valid range */
if (scan_number <= 0)
scan_number = 1;
if (cinfo->inputctl->eoi_reached &&
scan_number > cinfo->input_scan_number)
scan_number = cinfo->input_scan_number;
cinfo->output_scan_number = scan_number;
/* Perform any dummy output passes, and set up for the real pass */
return output_pass_setup(cinfo);
}
/*
* Finish up after an output pass in buffered-image mode.
*
* Returns FALSE if suspended. The return value need be inspected only if
* a suspending data source is used.
*/
GLOBAL(boolean)
jpeg_finish_output (j_decompress_ptr cinfo)
{
if ((cinfo->global_state == DSTATE_SCANNING ||
cinfo->global_state == DSTATE_RAW_OK) && cinfo->buffered_image) {
/* Terminate this pass. */
/* We do not require the whole pass to have been completed. */
(*cinfo->master->finish_output_pass) (cinfo);
cinfo->global_state = DSTATE_BUFPOST;
} else if (cinfo->global_state != DSTATE_BUFPOST) {
/* BUFPOST = repeat call after a suspension, anything else is error */
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
}
/* Read markers looking for SOS or EOI */
while (cinfo->input_scan_number <= cinfo->output_scan_number &&
! cinfo->inputctl->eoi_reached) {
if ((*cinfo->inputctl->consume_input) (cinfo) == JPEG_SUSPENDED)
return FALSE; /* Suspend, come back later */
}
cinfo->global_state = DSTATE_BUFIMAGE;
return TRUE;
}
#endif /* D_MULTISCAN_FILES_SUPPORTED */
dlib/external/libjpeg/jdatasrc.cpp 0 → 100644
View file @ 7cd5f664
/*
* jdatasrc.c
*
* Copyright (C) 1994-1996, Thomas G. Lane.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file contains decompression data source routines for the case of
* reading JPEG data from a file (or any stdio stream). While these routines
* are sufficient for most applications, some will want to use a different
* source manager.
* IMPORTANT: we assume that fread() will correctly transcribe an array of
* JOCTETs from 8-bit-wide elements on external storage. If char is wider
* than 8 bits on your machine, you may need to do some tweaking.
*/
/* this is not a core library module, so it doesn't define JPEG_INTERNALS */
#include "jinclude.h"
#include "jpeglib.h"
#include "jerror.h"
/* Expanded data source object for stdio input */
typedef struct {
struct jpeg_source_mgr pub; /* public fields */
FILE * infile; /* source stream */
JOCTET * buffer; /* start of buffer */
boolean start_of_file; /* have we gotten any data yet? */
} my_source_mgr;
typedef my_source_mgr * my_src_ptr;
#define INPUT_BUF_SIZE 4096 /* choose an efficiently fread'able size */
/*
* Initialize source --- called by jpeg_read_header
* before any data is actually read.
*/
METHODDEF(void)
init_source (j_decompress_ptr cinfo)
{
my_src_ptr src = (my_src_ptr) cinfo->src;
/* We reset the empty-input-file flag for each image,
* but we don't clear the input buffer.
* This is correct behavior for reading a series of images from one source.
*/
src->start_of_file = TRUE;
}
/*
* Fill the input buffer --- called whenever buffer is emptied.
*
* In typical applications, this should read fresh data into the buffer
* (ignoring the current state of next_input_byte & bytes_in_buffer),
* reset the pointer & count to the start of the buffer, and return TRUE
* indicating that the buffer has been reloaded. It is not necessary to
* fill the buffer entirely, only to obtain at least one more byte.
*
* There is no such thing as an EOF return. If the end of the file has been
* reached, the routine has a choice of ERREXIT() or inserting fake data into
* the buffer. In most cases, generating a warning message and inserting a
* fake EOI marker is the best course of action --- this will allow the
* decompressor to output however much of the image is there. However,
* the resulting error message is misleading if the real problem is an empty
* input file, so we handle that case specially.
*
* In applications that need to be able to suspend compression due to input
* not being available yet, a FALSE return indicates that no more data can be
* obtained right now, but more may be forthcoming later. In this situation,
* the decompressor will return to its caller (with an indication of the
* number of scanlines it has read, if any). The application should resume
* decompression after it has loaded more data into the input buffer. Note
* that there are substantial restrictions on the use of suspension --- see
* the documentation.
*
* When suspending, the decompressor will back up to a convenient restart point
* (typically the start of the current MCU). next_input_byte & bytes_in_buffer
* indicate where the restart point will be if the current call returns FALSE.
* Data beyond this point must be rescanned after resumption, so move it to
* the front of the buffer rather than discarding it.
*/
METHODDEF(boolean)
fill_input_buffer (j_decompress_ptr cinfo)
{
my_src_ptr src = (my_src_ptr) cinfo->src;
size_t nbytes;
nbytes = JFREAD(src->infile, src->buffer, INPUT_BUF_SIZE);
if (nbytes <= 0) {
if (src->start_of_file) /* Treat empty input file as fatal error */
ERREXIT(cinfo, JERR_INPUT_EMPTY);
WARNMS(cinfo, JWRN_JPEG_EOF);
/* Insert a fake EOI marker */
src->buffer[0] = (JOCTET) 0xFF;
src->buffer[1] = (JOCTET) JPEG_EOI;
nbytes = 2;
}
src->pub.next_input_byte = src->buffer;
src->pub.bytes_in_buffer = nbytes;
src->start_of_file = FALSE;
return TRUE;
}
/*
* Skip data --- used to skip over a potentially large amount of
* uninteresting data (such as an APPn marker).
*
* Writers of suspendable-input applications must note that skip_input_data
* is not granted the right to give a suspension return. If the skip extends
* beyond the data currently in the buffer, the buffer can be marked empty so
* that the next read will cause a fill_input_buffer call that can suspend.
* Arranging for additional bytes to be discarded before reloading the input
* buffer is the application writer's problem.
*/
METHODDEF(void)
skip_input_data (j_decompress_ptr cinfo, long num_bytes)
{
my_src_ptr src = (my_src_ptr) cinfo->src;
/* Just a dumb implementation for now. Could use fseek() except
* it doesn't work on pipes. Not clear that being smart is worth
* any trouble anyway --- large skips are infrequent.
*/
if (num_bytes > 0) {
while (num_bytes > (long) src->pub.bytes_in_buffer) {
num_bytes -= (long) src->pub.bytes_in_buffer;
(void) fill_input_buffer(cinfo);
/* note we assume that fill_input_buffer will never return FALSE,
* so suspension need not be handled.
*/
}
src->pub.next_input_byte += (size_t) num_bytes;
src->pub.bytes_in_buffer -= (size_t) num_bytes;
}
}
/*
* An additional method that can be provided by data source modules is the
* resync_to_restart method for error recovery in the presence of RST markers.
* For the moment, this source module just uses the default resync method
* provided by the JPEG library. That method assumes that no backtracking
* is possible.
*/
/*
* Terminate source --- called by jpeg_finish_decompress
* after all data has been read. Often a no-op.
*
* NB: *not* called by jpeg_abort or jpeg_destroy; surrounding
* application must deal with any cleanup that should happen even
* for error exit.
*/
METHODDEF(void)
term_source (j_decompress_ptr cinfo)
{
/* no work necessary here */
}
/*
* Prepare for input from a stdio stream.
* The caller must have already opened the stream, and is responsible
* for closing it after finishing decompression.
*/
GLOBAL(void)
jpeg_stdio_src (j_decompress_ptr cinfo, FILE * infile)
{
my_src_ptr src;
/* The source object and input buffer are made permanent so that a series
* of JPEG images can be read from the same file by calling jpeg_stdio_src
* only before the first one. (If we discarded the buffer at the end of
* one image, we'd likely lose the start of the next one.)
* This makes it unsafe to use this manager and a different source
* manager serially with the same JPEG object. Caveat programmer.
*/
if (cinfo->src == NULL) { /* first time for this JPEG object? */
cinfo->src = (struct jpeg_source_mgr *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
SIZEOF(my_source_mgr));
src = (my_src_ptr) cinfo->src;
src->buffer = (JOCTET *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
INPUT_BUF_SIZE * SIZEOF(JOCTET));
}
src = (my_src_ptr) cinfo->src;
src->pub.init_source = init_source;
src->pub.fill_input_buffer = fill_input_buffer;
src->pub.skip_input_data = skip_input_data;
src->pub.resync_to_restart = jpeg_resync_to_restart; /* use default method */
src->pub.term_source = term_source;
src->infile = infile;
src->pub.bytes_in_buffer = 0; /* forces fill_input_buffer on first read */
src->pub.next_input_byte = NULL; /* until buffer loaded */
}
dlib/external/libjpeg/jdcoefct.cpp 0 → 100644
View file @ 7cd5f664
/*
* jdcoefct.c
*
* Copyright (C) 1994-1997, Thomas G. Lane.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file contains the coefficient buffer controller for decompression.
* This controller is the top level of the JPEG decompressor proper.
* The coefficient buffer lies between entropy decoding and inverse-DCT steps.
*
* In buffered-image mode, this controller is the interface between
* input-oriented processing and output-oriented processing.
* Also, the input side (only) is used when reading a file for transcoding.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
/* Block smoothing is only applicable for progressive JPEG, so: */
#ifndef D_PROGRESSIVE_SUPPORTED
#undef BLOCK_SMOOTHING_SUPPORTED
#endif
/* Private buffer controller object */
typedef struct {
struct jpeg_d_coef_controller pub; /* public fields */
/* These variables keep track of the current location of the input side. */
/* cinfo->input_iMCU_row is also used for this. */
JDIMENSION MCU_ctr; /* counts MCUs processed in current row */
int MCU_vert_offset; /* counts MCU rows within iMCU row */
int MCU_rows_per_iMCU_row; /* number of such rows needed */
/* The output side's location is represented by cinfo->output_iMCU_row. */
/* In single-pass modes, it's sufficient to buffer just one MCU.
* We allocate a workspace of D_MAX_BLOCKS_IN_MCU coefficient blocks,
* and let the entropy decoder write into that workspace each time.
* (On 80x86, the workspace is FAR even though it's not really very big;
* this is to keep the module interfaces unchanged when a large coefficient
* buffer is necessary.)
* In multi-pass modes, this array points to the current MCU's blocks
* within the virtual arrays; it is used only by the input side.
*/
JBLOCKROW MCU_buffer[D_MAX_BLOCKS_IN_MCU];
#ifdef D_MULTISCAN_FILES_SUPPORTED
/* In multi-pass modes, we need a virtual block array for each component. */
jvirt_barray_ptr whole_image[MAX_COMPONENTS];
#endif
#ifdef BLOCK_SMOOTHING_SUPPORTED
/* When doing block smoothing, we latch coefficient Al values here */
int * coef_bits_latch;
#define SAVED_COEFS 6 /* we save coef_bits[0..5] */
#endif
} my_coef_controller;
typedef my_coef_controller * my_coef_ptr;
/* Forward declarations */
METHODDEF(int) decompress_onepass
JPP((j_decompress_ptr cinfo, JSAMPIMAGE output_buf));
#ifdef D_MULTISCAN_FILES_SUPPORTED
METHODDEF(int) decompress_data
JPP((j_decompress_ptr cinfo, JSAMPIMAGE output_buf));
#endif
#ifdef BLOCK_SMOOTHING_SUPPORTED
LOCAL(boolean) smoothing_ok JPP((j_decompress_ptr cinfo));
METHODDEF(int) decompress_smooth_data
JPP((j_decompress_ptr cinfo, JSAMPIMAGE output_buf));
#endif
LOCAL(void)
start_iMCU_row (j_decompress_ptr cinfo)
/* Reset within-iMCU-row counters for a new row (input side) */
{
my_coef_ptr coef = (my_coef_ptr) cinfo->coef;
/* In an interleaved scan, an MCU row is the same as an iMCU row.
* In a noninterleaved scan, an iMCU row has v_samp_factor MCU rows.
* But at the bottom of the image, process only what's left.
*/
if (cinfo->comps_in_scan > 1) {
coef->MCU_rows_per_iMCU_row = 1;
} else {
if (cinfo->input_iMCU_row < (cinfo->total_iMCU_rows-1))
coef->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->v_samp_factor;
else
coef->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->last_row_height;
}
coef->MCU_ctr = 0;
coef->MCU_vert_offset = 0;
}
/*
* Initialize for an input processing pass.
*/
METHODDEF(void)
start_input_pass (j_decompress_ptr cinfo)
{
cinfo->input_iMCU_row = 0;
start_iMCU_row(cinfo);
}
/*
* Initialize for an output processing pass.
*/
METHODDEF(void)
start_output_pass (j_decompress_ptr cinfo)
{
#ifdef BLOCK_SMOOTHING_SUPPORTED
my_coef_ptr coef = (my_coef_ptr) cinfo->coef;
/* If multipass, check to see whether to use block smoothing on this pass */
if (coef->pub.coef_arrays != NULL) {
if (cinfo->do_block_smoothing && smoothing_ok(cinfo))
coef->pub.decompress_data = decompress_smooth_data;
else
coef->pub.decompress_data = decompress_data;
}
#endif
cinfo->output_iMCU_row = 0;
}
/*
* Decompress and return some data in the single-pass case.
* Always attempts to emit one fully interleaved MCU row ("iMCU" row).
* Input and output must run in lockstep since we have only a one-MCU buffer.
* Return value is JPEG_ROW_COMPLETED, JPEG_SCAN_COMPLETED, or JPEG_SUSPENDED.
*
* NB: output_buf contains a plane for each component in image,
* which we index according to the component's SOF position.
*/
METHODDEF(int)
decompress_onepass (j_decompress_ptr cinfo, JSAMPIMAGE output_buf)
{
my_coef_ptr coef = (my_coef_ptr) cinfo->coef;
JDIMENSION MCU_col_num; /* index of current MCU within row */
JDIMENSION last_MCU_col = cinfo->MCUs_per_row - 1;
JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1;
int blkn, ci, xindex, yindex, yoffset, useful_width;
JSAMPARRAY output_ptr;
JDIMENSION start_col, output_col;
jpeg_component_info *compptr;
inverse_DCT_method_ptr inverse_DCT;
/* Loop to process as much as one whole iMCU row */
for (yoffset = coef->MCU_vert_offset; yoffset < coef->MCU_rows_per_iMCU_row;
yoffset++) {
for (MCU_col_num = coef->MCU_ctr; MCU_col_num <= last_MCU_col;
MCU_col_num++) {
/* Try to fetch an MCU. Entropy decoder expects buffer to be zeroed. */
jzero_far((void FAR *) coef->MCU_buffer[0],
(size_t) (cinfo->blocks_in_MCU * SIZEOF(JBLOCK)));
if (! (*cinfo->entropy->decode_mcu) (cinfo, coef->MCU_buffer)) {
/* Suspension forced; update state counters and exit */
coef->MCU_vert_offset = yoffset;
coef->MCU_ctr = MCU_col_num;
return JPEG_SUSPENDED;
}
/* Determine where data should go in output_buf and do the IDCT thing.
* We skip dummy blocks at the right and bottom edges (but blkn gets
* incremented past them!). Note the inner loop relies on having
* allocated the MCU_buffer[] blocks sequentially.
*/
blkn = 0; /* index of current DCT block within MCU */
for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
compptr = cinfo->cur_comp_info[ci];
/* Don't bother to IDCT an uninteresting component. */
if (! compptr->component_needed) {
blkn += compptr->MCU_blocks;
continue;
}
inverse_DCT = cinfo->idct->inverse_DCT[compptr->component_index];
useful_width = (MCU_col_num < last_MCU_col) ? compptr->MCU_width
: compptr->last_col_width;
output_ptr = output_buf[compptr->component_index] +
yoffset * compptr->DCT_scaled_size;
start_col = MCU_col_num * compptr->MCU_sample_width;
for (yindex = 0; yindex < compptr->MCU_height; yindex++) {
if (cinfo->input_iMCU_row < last_iMCU_row ||
yoffset+yindex < compptr->last_row_height) {
output_col = start_col;
for (xindex = 0; xindex < useful_width; xindex++) {
(*inverse_DCT) (cinfo, compptr,
(JCOEFPTR) coef->MCU_buffer[blkn+xindex],
output_ptr, output_col);
output_col += compptr->DCT_scaled_size;
}
}
blkn += compptr->MCU_width;
output_ptr += compptr->DCT_scaled_size;
}
}
}
/* Completed an MCU row, but perhaps not an iMCU row */
coef->MCU_ctr = 0;
}
/* Completed the iMCU row, advance counters for next one */
cinfo->output_iMCU_row++;
if (++(cinfo->input_iMCU_row) < cinfo->total_iMCU_rows) {
start_iMCU_row(cinfo);
return JPEG_ROW_COMPLETED;
}
/* Completed the scan */
(*cinfo->inputctl->finish_input_pass) (cinfo);
return JPEG_SCAN_COMPLETED;
}
/*
* Dummy consume-input routine for single-pass operation.
*/
METHODDEF(int)
dummy_consume_data (j_decompress_ptr cinfo)
{
return JPEG_SUSPENDED; /* Always indicate nothing was done */
}
#ifdef D_MULTISCAN_FILES_SUPPORTED
/*
* Consume input data and store it in the full-image coefficient buffer.
* We read as much as one fully interleaved MCU row ("iMCU" row) per call,
* ie, v_samp_factor block rows for each component in the scan.
* Return value is JPEG_ROW_COMPLETED, JPEG_SCAN_COMPLETED, or JPEG_SUSPENDED.
*/
METHODDEF(int)
consume_data (j_decompress_ptr cinfo)
{
my_coef_ptr coef = (my_coef_ptr) cinfo->coef;
JDIMENSION MCU_col_num; /* index of current MCU within row */
int blkn, ci, xindex, yindex, yoffset;
JDIMENSION start_col;
JBLOCKARRAY buffer[MAX_COMPS_IN_SCAN];
JBLOCKROW buffer_ptr;
jpeg_component_info *compptr;
/* Align the virtual buffers for the components used in this scan. */
for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
compptr = cinfo->cur_comp_info[ci];
buffer[ci] = (*cinfo->mem->access_virt_barray)
((j_common_ptr) cinfo, coef->whole_image[compptr->component_index],
cinfo->input_iMCU_row * compptr->v_samp_factor,
(JDIMENSION) compptr->v_samp_factor, TRUE);
/* Note: entropy decoder expects buffer to be zeroed,
* but this is handled automatically by the memory manager
* because we requested a pre-zeroed array.
*/
}
/* Loop to process one whole iMCU row */
for (yoffset = coef->MCU_vert_offset; yoffset < coef->MCU_rows_per_iMCU_row;
yoffset++) {
for (MCU_col_num = coef->MCU_ctr; MCU_col_num < cinfo->MCUs_per_row;
MCU_col_num++) {
/* Construct list of pointers to DCT blocks belonging to this MCU */
blkn = 0; /* index of current DCT block within MCU */
for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
compptr = cinfo->cur_comp_info[ci];
start_col = MCU_col_num * compptr->MCU_width;
for (yindex = 0; yindex < compptr->MCU_height; yindex++) {
buffer_ptr = buffer[ci][yindex+yoffset] + start_col;
for (xindex = 0; xindex < compptr->MCU_width; xindex++) {
coef->MCU_buffer[blkn++] = buffer_ptr++;
}
}
}
/* Try to fetch the MCU. */
if (! (*cinfo->entropy->decode_mcu) (cinfo, coef->MCU_buffer)) {
/* Suspension forced; update state counters and exit */
coef->MCU_vert_offset = yoffset;
coef->MCU_ctr = MCU_col_num;
return JPEG_SUSPENDED;
}
}
/* Completed an MCU row, but perhaps not an iMCU row */
coef->MCU_ctr = 0;
}
/* Completed the iMCU row, advance counters for next one */
if (++(cinfo->input_iMCU_row) < cinfo->total_iMCU_rows) {
start_iMCU_row(cinfo);
return JPEG_ROW_COMPLETED;
}
/* Completed the scan */
(*cinfo->inputctl->finish_input_pass) (cinfo);
return JPEG_SCAN_COMPLETED;
}
/*
* Decompress and return some data in the multi-pass case.
* Always attempts to emit one fully interleaved MCU row ("iMCU" row).
* Return value is JPEG_ROW_COMPLETED, JPEG_SCAN_COMPLETED, or JPEG_SUSPENDED.
*
* NB: output_buf contains a plane for each component in image.
*/
METHODDEF(int)
decompress_data (j_decompress_ptr cinfo, JSAMPIMAGE output_buf)
{
my_coef_ptr coef = (my_coef_ptr) cinfo->coef;
JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1;
JDIMENSION block_num;
int ci, block_row, block_rows;
JBLOCKARRAY buffer;
JBLOCKROW buffer_ptr;
JSAMPARRAY output_ptr;
JDIMENSION output_col;
jpeg_component_info *compptr;
inverse_DCT_method_ptr inverse_DCT;
/* Force some input to be done if we are getting ahead of the input. */
while (cinfo->input_scan_number < cinfo->output_scan_number ||
(cinfo->input_scan_number == cinfo->output_scan_number &&
cinfo->input_iMCU_row <= cinfo->output_iMCU_row)) {
if ((*cinfo->inputctl->consume_input)(cinfo) == JPEG_SUSPENDED)
return JPEG_SUSPENDED;
}
/* OK, output from the virtual arrays. */
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
/* Don't bother to IDCT an uninteresting component. */
if (! compptr->component_needed)
continue;
/* Align the virtual buffer for this component. */
buffer = (*cinfo->mem->access_virt_barray)
((j_common_ptr) cinfo, coef->whole_image[ci],
cinfo->output_iMCU_row * compptr->v_samp_factor,
(JDIMENSION) compptr->v_samp_factor, FALSE);
/* Count non-dummy DCT block rows in this iMCU row. */
if (cinfo->output_iMCU_row < last_iMCU_row)
block_rows = compptr->v_samp_factor;
else {
/* NB: can't use last_row_height here; it is input-side-dependent! */
block_rows = (int) (compptr->height_in_blocks % compptr->v_samp_factor);
if (block_rows == 0) block_rows = compptr->v_samp_factor;
}
inverse_DCT = cinfo->idct->inverse_DCT[ci];
output_ptr = output_buf[ci];
/* Loop over all DCT blocks to be processed. */
for (block_row = 0; block_row < block_rows; block_row++) {
buffer_ptr = buffer[block_row];
output_col = 0;
for (block_num = 0; block_num < compptr->width_in_blocks; block_num++) {
(*inverse_DCT) (cinfo, compptr, (JCOEFPTR) buffer_ptr,
output_ptr, output_col);
buffer_ptr++;
output_col += compptr->DCT_scaled_size;
}
output_ptr += compptr->DCT_scaled_size;
}
}
if (++(cinfo->output_iMCU_row) < cinfo->total_iMCU_rows)
return JPEG_ROW_COMPLETED;
return JPEG_SCAN_COMPLETED;
}
#endif /* D_MULTISCAN_FILES_SUPPORTED */
#ifdef BLOCK_SMOOTHING_SUPPORTED
/*
* This code applies interblock smoothing as described by section K.8
* of the JPEG standard: the first 5 AC coefficients are estimated from
* the DC values of a DCT block and its 8 neighboring blocks.
* We apply smoothing only for progressive JPEG decoding, and only if
* the coefficients it can estimate are not yet known to full precision.
*/
/* Natural-order array positions of the first 5 zigzag-order coefficients */
#define Q01_POS 1
#define Q10_POS 8
#define Q20_POS 16
#define Q11_POS 9
#define Q02_POS 2
/*
* Determine whether block smoothing is applicable and safe.
* We also latch the current states of the coef_bits[] entries for the
* AC coefficients; otherwise, if the input side of the decompressor
* advances into a new scan, we might think the coefficients are known
* more accurately than they really are.
*/
LOCAL(boolean)
smoothing_ok (j_decompress_ptr cinfo)
{
my_coef_ptr coef = (my_coef_ptr) cinfo->coef;
boolean smoothing_useful = FALSE;
int ci, coefi;
jpeg_component_info *compptr;
JQUANT_TBL * qtable;
int * coef_bits;
int * coef_bits_latch;
if (! cinfo->progressive_mode || cinfo->coef_bits == NULL)
return FALSE;
/* Allocate latch area if not already done */
if (coef->coef_bits_latch == NULL)
coef->coef_bits_latch = (int *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
cinfo->num_components *
(SAVED_COEFS * SIZEOF(int)));
coef_bits_latch = coef->coef_bits_latch;
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
/* All components' quantization values must already be latched. */
if ((qtable = compptr->quant_table) == NULL)
return FALSE;
/* Verify DC & first 5 AC quantizers are nonzero to avoid zero-divide. */
if (qtable->quantval[0] == 0 ||
qtable->quantval[Q01_POS] == 0 ||
qtable->quantval[Q10_POS] == 0 ||
qtable->quantval[Q20_POS] == 0 ||
qtable->quantval[Q11_POS] == 0 ||
qtable->quantval[Q02_POS] == 0)
return FALSE;
/* DC values must be at least partly known for all components. */
coef_bits = cinfo->coef_bits[ci];
if (coef_bits[0] < 0)
return FALSE;
/* Block smoothing is helpful if some AC coefficients remain inaccurate. */
for (coefi = 1; coefi <= 5; coefi++) {
coef_bits_latch[coefi] = coef_bits[coefi];
if (coef_bits[coefi] != 0)
smoothing_useful = TRUE;
}
coef_bits_latch += SAVED_COEFS;
}
return smoothing_useful;
}
/*
* Variant of decompress_data for use when doing block smoothing.
*/
METHODDEF(int)
decompress_smooth_data (j_decompress_ptr cinfo, JSAMPIMAGE output_buf)
{
my_coef_ptr coef = (my_coef_ptr) cinfo->coef;
JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1;
JDIMENSION block_num, last_block_column;
int ci, block_row, block_rows, access_rows;
JBLOCKARRAY buffer;
JBLOCKROW buffer_ptr, prev_block_row, next_block_row;
JSAMPARRAY output_ptr;
JDIMENSION output_col;
jpeg_component_info *compptr;
inverse_DCT_method_ptr inverse_DCT;
boolean first_row, last_row;
JBLOCK workspace;
int *coef_bits;
JQUANT_TBL *quanttbl;
INT32 Q00,Q01,Q02,Q10,Q11,Q20, num;
int DC1,DC2,DC3,DC4,DC5,DC6,DC7,DC8,DC9;
int Al, pred;
/* Force some input to be done if we are getting ahead of the input. */
while (cinfo->input_scan_number <= cinfo->output_scan_number &&
! cinfo->inputctl->eoi_reached) {
if (cinfo->input_scan_number == cinfo->output_scan_number) {
/* If input is working on current scan, we ordinarily want it to
* have completed the current row. But if input scan is DC,
* we want it to keep one row ahead so that next block row's DC
* values are up to date.
*/
JDIMENSION delta = (cinfo->Ss == 0) ? 1 : 0;
if (cinfo->input_iMCU_row > cinfo->output_iMCU_row+delta)
break;
}
if ((*cinfo->inputctl->consume_input)(cinfo) == JPEG_SUSPENDED)
return JPEG_SUSPENDED;
}
/* OK, output from the virtual arrays. */
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
/* Don't bother to IDCT an uninteresting component. */
if (! compptr->component_needed)
continue;
/* Count non-dummy DCT block rows in this iMCU row. */
if (cinfo->output_iMCU_row < last_iMCU_row) {
block_rows = compptr->v_samp_factor;
access_rows = block_rows * 2; /* this and next iMCU row */
last_row = FALSE;
} else {
/* NB: can't use last_row_height here; it is input-side-dependent! */
block_rows = (int) (compptr->height_in_blocks % compptr->v_samp_factor);
if (block_rows == 0) block_rows = compptr->v_samp_factor;
access_rows = block_rows; /* this iMCU row only */
last_row = TRUE;
}
/* Align the virtual buffer for this component. */
if (cinfo->output_iMCU_row > 0) {
access_rows += compptr->v_samp_factor; /* prior iMCU row too */
buffer = (*cinfo->mem->access_virt_barray)
((j_common_ptr) cinfo, coef->whole_image[ci],
(cinfo->output_iMCU_row - 1) * compptr->v_samp_factor,
(JDIMENSION) access_rows, FALSE);
buffer += compptr->v_samp_factor; /* point to current iMCU row */
first_row = FALSE;
} else {
buffer = (*cinfo->mem->access_virt_barray)
((j_common_ptr) cinfo, coef->whole_image[ci],
(JDIMENSION) 0, (JDIMENSION) access_rows, FALSE);
first_row = TRUE;
}
/* Fetch component-dependent info */
coef_bits = coef->coef_bits_latch + (ci * SAVED_COEFS);
quanttbl = compptr->quant_table;
Q00 = quanttbl->quantval[0];
Q01 = quanttbl->quantval[Q01_POS];
Q10 = quanttbl->quantval[Q10_POS];
Q20 = quanttbl->quantval[Q20_POS];
Q11 = quanttbl->quantval[Q11_POS];
Q02 = quanttbl->quantval[Q02_POS];
inverse_DCT = cinfo->idct->inverse_DCT[ci];
output_ptr = output_buf[ci];
/* Loop over all DCT blocks to be processed. */
for (block_row = 0; block_row < block_rows; block_row++) {
buffer_ptr = buffer[block_row];
if (first_row && block_row == 0)
prev_block_row = buffer_ptr;
else
prev_block_row = buffer[block_row-1];
if (last_row && block_row == block_rows-1)
next_block_row = buffer_ptr;
else
next_block_row = buffer[block_row+1];
/* We fetch the surrounding DC values using a sliding-register approach.
* Initialize all nine here so as to do the right thing on narrow pics.
*/
DC1 = DC2 = DC3 = (int) prev_block_row[0][0];
DC4 = DC5 = DC6 = (int) buffer_ptr[0][0];
DC7 = DC8 = DC9 = (int) next_block_row[0][0];
output_col = 0;
last_block_column = compptr->width_in_blocks - 1;
for (block_num = 0; block_num <= last_block_column; block_num++) {
/* Fetch current DCT block into workspace so we can modify it. */
jcopy_block_row(buffer_ptr, (JBLOCKROW) workspace, (JDIMENSION) 1);
/* Update DC values */
if (block_num < last_block_column) {
DC3 = (int) prev_block_row[1][0];
DC6 = (int) buffer_ptr[1][0];
DC9 = (int) next_block_row[1][0];
}
/* Compute coefficient estimates per K.8.
* An estimate is applied only if coefficient is still zero,
* and is not known to be fully accurate.
*/
/* AC01 */
if ((Al=coef_bits[1]) != 0 && workspace[1] == 0) {
num = 36 * Q00 * (DC4 - DC6);
if (num >= 0) {
pred = (int) (((Q01<<7) + num) / (Q01<<8));
if (Al > 0 && pred >= (1<<Al))
pred = (1<<Al)-1;
} else {
pred = (int) (((Q01<<7) - num) / (Q01<<8));
if (Al > 0 && pred >= (1<<Al))
pred = (1<<Al)-1;
pred = -pred;
}
workspace[1] = (JCOEF) pred;
}
/* AC10 */
if ((Al=coef_bits[2]) != 0 && workspace[8] == 0) {
num = 36 * Q00 * (DC2 - DC8);
if (num >= 0) {
pred = (int) (((Q10<<7) + num) / (Q10<<8));
if (Al > 0 && pred >= (1<<Al))
pred = (1<<Al)-1;
} else {
pred = (int) (((Q10<<7) - num) / (Q10<<8));
if (Al > 0 && pred >= (1<<Al))
pred = (1<<Al)-1;
pred = -pred;
}
workspace[8] = (JCOEF) pred;
}
/* AC20 */
if ((Al=coef_bits[3]) != 0 && workspace[16] == 0) {
num = 9 * Q00 * (DC2 + DC8 - 2*DC5);
if (num >= 0) {
pred = (int) (((Q20<<7) + num) / (Q20<<8));
if (Al > 0 && pred >= (1<<Al))
pred = (1<<Al)-1;
} else {
pred = (int) (((Q20<<7) - num) / (Q20<<8));
if (Al > 0 && pred >= (1<<Al))
pred = (1<<Al)-1;
pred = -pred;
}
workspace[16] = (JCOEF) pred;
}
/* AC11 */
if ((Al=coef_bits[4]) != 0 && workspace[9] == 0) {
num = 5 * Q00 * (DC1 - DC3 - DC7 + DC9);
if (num >= 0) {
pred = (int) (((Q11<<7) + num) / (Q11<<8));
if (Al > 0 && pred >= (1<<Al))
pred = (1<<Al)-1;
} else {
pred = (int) (((Q11<<7) - num) / (Q11<<8));
if (Al > 0 && pred >= (1<<Al))
pred = (1<<Al)-1;
pred = -pred;
}
workspace[9] = (JCOEF) pred;
}
/* AC02 */
if ((Al=coef_bits[5]) != 0 && workspace[2] == 0) {
num = 9 * Q00 * (DC4 + DC6 - 2*DC5);
if (num >= 0) {
pred = (int) (((Q02<<7) + num) / (Q02<<8));
if (Al > 0 && pred >= (1<<Al))
pred = (1<<Al)-1;
} else {
pred = (int) (((Q02<<7) - num) / (Q02<<8));
if (Al > 0 && pred >= (1<<Al))
pred = (1<<Al)-1;
pred = -pred;
}
workspace[2] = (JCOEF) pred;
}
/* OK, do the IDCT */
(*inverse_DCT) (cinfo, compptr, (JCOEFPTR) workspace,
output_ptr, output_col);
/* Advance for next column */
DC1 = DC2; DC2 = DC3;
DC4 = DC5; DC5 = DC6;
DC7 = DC8; DC8 = DC9;
buffer_ptr++, prev_block_row++, next_block_row++;
output_col += compptr->DCT_scaled_size;
}
output_ptr += compptr->DCT_scaled_size;
}
}
if (++(cinfo->output_iMCU_row) < cinfo->total_iMCU_rows)
return JPEG_ROW_COMPLETED;
return JPEG_SCAN_COMPLETED;
}
#endif /* BLOCK_SMOOTHING_SUPPORTED */
/*
* Initialize coefficient buffer controller.
*/
GLOBAL(void)
jinit_d_coef_controller (j_decompress_ptr cinfo, boolean need_full_buffer)
{
my_coef_ptr coef;
coef = (my_coef_ptr)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
SIZEOF(my_coef_controller));
cinfo->coef = (struct jpeg_d_coef_controller *) coef;
coef->pub.start_input_pass = start_input_pass;
coef->pub.start_output_pass = start_output_pass;
#ifdef BLOCK_SMOOTHING_SUPPORTED
coef->coef_bits_latch = NULL;
#endif
/* Create the coefficient buffer. */
if (need_full_buffer) {
#ifdef D_MULTISCAN_FILES_SUPPORTED
/* Allocate a full-image virtual array for each component, */
/* padded to a multiple of samp_factor DCT blocks in each direction. */
/* Note we ask for a pre-zeroed array. */
int ci, access_rows;
jpeg_component_info *compptr;
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
access_rows = compptr->v_samp_factor;
#ifdef BLOCK_SMOOTHING_SUPPORTED
/* If block smoothing could be used, need a bigger window */
if (cinfo->progressive_mode)
access_rows *= 3;
#endif
coef->whole_image[ci] = (*cinfo->mem->request_virt_barray)
((j_common_ptr) cinfo, JPOOL_IMAGE, TRUE,
(JDIMENSION) jround_up((long) compptr->width_in_blocks,
(long) compptr->h_samp_factor),
(JDIMENSION) jround_up((long) compptr->height_in_blocks,
(long) compptr->v_samp_factor),
(JDIMENSION) access_rows);
}
coef->pub.consume_data = consume_data;
coef->pub.decompress_data = decompress_data;
coef->pub.coef_arrays = coef->whole_image; /* link to virtual arrays */
#else
ERREXIT(cinfo, JERR_NOT_COMPILED);
#endif
} else {
/* We only need a single-MCU buffer. */
JBLOCKROW buffer;
int i;
buffer = (JBLOCKROW)
(*cinfo->mem->alloc_large) ((j_common_ptr) cinfo, JPOOL_IMAGE,
D_MAX_BLOCKS_IN_MCU * SIZEOF(JBLOCK));
for (i = 0; i < D_MAX_BLOCKS_IN_MCU; i++) {
coef->MCU_buffer[i] = buffer + i;
}
coef->pub.consume_data = dummy_consume_data;
coef->pub.decompress_data = decompress_onepass;
coef->pub.coef_arrays = NULL; /* flag for no virtual arrays */
}
}
dlib/external/libjpeg/jdcolor.cpp 0 → 100644
View file @ 7cd5f664
/*
* jdcolor.c
*
* Copyright (C) 1991-1997, Thomas G. Lane.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file contains output colorspace conversion routines.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
/* Private subobject */
typedef struct {
struct jpeg_color_deconverter pub; /* public fields */
/* Private state for YCC->RGB conversion */
int * Cr_r_tab; /* => table for Cr to R conversion */
int * Cb_b_tab; /* => table for Cb to B conversion */
INT32 * Cr_g_tab; /* => table for Cr to G conversion */
INT32 * Cb_g_tab; /* => table for Cb to G conversion */
} my_color_deconverter;
typedef my_color_deconverter * my_cconvert_ptr;
/**************** YCbCr -> RGB conversion: most common case **************/
/*
* YCbCr is defined per CCIR 601-1, except that Cb and Cr are
* normalized to the range 0..MAXJSAMPLE rather than -0.5 .. 0.5.
* The conversion equations to be implemented are therefore
* R = Y + 1.40200 * Cr
* G = Y - 0.34414 * Cb - 0.71414 * Cr
* B = Y + 1.77200 * Cb
* where Cb and Cr represent the incoming values less CENTERJSAMPLE.
* (These numbers are derived from TIFF 6.0 section 21, dated 3-June-92.)
*
* To avoid floating-point arithmetic, we represent the fractional constants
* as integers scaled up by 2^16 (about 4 digits precision); we have to divide
* the products by 2^16, with appropriate rounding, to get the correct answer.
* Notice that Y, being an integral input, does not contribute any fraction
* so it need not participate in the rounding.
*
* For even more speed, we avoid doing any multiplications in the inner loop
* by precalculating the constants times Cb and Cr for all possible values.
* For 8-bit JSAMPLEs this is very reasonable (only 256 entries per table);
* for 12-bit samples it is still acceptable. It's not very reasonable for
* 16-bit samples, but if you want lossless storage you shouldn't be changing
* colorspace anyway.
* The Cr=>R and Cb=>B values can be rounded to integers in advance; the
* values for the G calculation are left scaled up, since we must add them
* together before rounding.
*/
#define SCALEBITS 16 /* speediest right-shift on some machines */
#define ONE_HALF ((INT32) 1 << (SCALEBITS-1))
#define FIX(x) ((INT32) ((x) * (1L<<SCALEBITS) + 0.5))
/*
* Initialize tables for YCC->RGB colorspace conversion.
*/
LOCAL(void)
build_ycc_rgb_table (j_decompress_ptr cinfo)
{
my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;
int i;
INT32 x;
SHIFT_TEMPS
cconvert->Cr_r_tab = (int *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
(MAXJSAMPLE+1) * SIZEOF(int));
cconvert->Cb_b_tab = (int *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
(MAXJSAMPLE+1) * SIZEOF(int));
cconvert->Cr_g_tab = (INT32 *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
(MAXJSAMPLE+1) * SIZEOF(INT32));
cconvert->Cb_g_tab = (INT32 *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
(MAXJSAMPLE+1) * SIZEOF(INT32));
for (i = 0, x = -CENTERJSAMPLE; i <= MAXJSAMPLE; i++, x++) {
/* i is the actual input pixel value, in the range 0..MAXJSAMPLE */
/* The Cb or Cr value we are thinking of is x = i - CENTERJSAMPLE */
/* Cr=>R value is nearest int to 1.40200 * x */
cconvert->Cr_r_tab[i] = (int)
RIGHT_SHIFT(FIX(1.40200) * x + ONE_HALF, SCALEBITS);
/* Cb=>B value is nearest int to 1.77200 * x */
cconvert->Cb_b_tab[i] = (int)
RIGHT_SHIFT(FIX(1.77200) * x + ONE_HALF, SCALEBITS);
/* Cr=>G value is scaled-up -0.71414 * x */
cconvert->Cr_g_tab[i] = (- FIX(0.71414)) * x;
/* Cb=>G value is scaled-up -0.34414 * x */
/* We also add in ONE_HALF so that need not do it in inner loop */
cconvert->Cb_g_tab[i] = (- FIX(0.34414)) * x + ONE_HALF;
}
}
/*
* Convert some rows of samples to the output colorspace.
*
* Note that we change from noninterleaved, one-plane-per-component format
* to interleaved-pixel format. The output buffer is therefore three times
* as wide as the input buffer.
* A starting row offset is provided only for the input buffer. The caller
* can easily adjust the passed output_buf value to accommodate any row
* offset required on that side.
*/
METHODDEF(void)
ycc_rgb_convert (j_decompress_ptr cinfo,
JSAMPIMAGE input_buf, JDIMENSION input_row,
JSAMPARRAY output_buf, int num_rows)
{
my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;
register int y, cb, cr;
register JSAMPROW outptr;
register JSAMPROW inptr0, inptr1, inptr2;
register JDIMENSION col;
JDIMENSION num_cols = cinfo->output_width;
/* copy these pointers into registers if possible */
register JSAMPLE * range_limit = cinfo->sample_range_limit;
register int * Crrtab = cconvert->Cr_r_tab;
register int * Cbbtab = cconvert->Cb_b_tab;
register INT32 * Crgtab = cconvert->Cr_g_tab;
register INT32 * Cbgtab = cconvert->Cb_g_tab;
SHIFT_TEMPS
while (--num_rows >= 0) {
inptr0 = input_buf[0][input_row];
inptr1 = input_buf[1][input_row];
inptr2 = input_buf[2][input_row];
input_row++;
outptr = *output_buf++;
for (col = 0; col < num_cols; col++) {
y = GETJSAMPLE(inptr0[col]);
cb = GETJSAMPLE(inptr1[col]);
cr = GETJSAMPLE(inptr2[col]);
/* Range-limiting is essential due to noise introduced by DCT losses. */
outptr[RGB_RED] = range_limit[y + Crrtab[cr]];
outptr[RGB_GREEN] = range_limit[y +
((int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr],
SCALEBITS))];
outptr[RGB_BLUE] = range_limit[y + Cbbtab[cb]];
outptr += RGB_PIXELSIZE;
}
}
}
/**************** Cases other than YCbCr -> RGB **************/
/*
* Color conversion for no colorspace change: just copy the data,
* converting from separate-planes to interleaved representation.
*/
METHODDEF(void)
null_convert (j_decompress_ptr cinfo,
JSAMPIMAGE input_buf, JDIMENSION input_row,
JSAMPARRAY output_buf, int num_rows)
{
register JSAMPROW inptr, outptr;
register JDIMENSION count;
register int num_components = cinfo->num_components;
JDIMENSION num_cols = cinfo->output_width;
int ci;
while (--num_rows >= 0) {
for (ci = 0; ci < num_components; ci++) {
inptr = input_buf[ci][input_row];
outptr = output_buf[0] + ci;
for (count = num_cols; count > 0; count--) {
*outptr = *inptr++; /* needn't bother with GETJSAMPLE() here */
outptr += num_components;
}
}
input_row++;
output_buf++;
}
}
/*
* Color conversion for grayscale: just copy the data.
* This also works for YCbCr -> grayscale conversion, in which
* we just copy the Y (luminance) component and ignore chrominance.
*/
METHODDEF(void)
grayscale_convert (j_decompress_ptr cinfo,
JSAMPIMAGE input_buf, JDIMENSION input_row,
JSAMPARRAY output_buf, int num_rows)
{
jcopy_sample_rows(input_buf[0], (int) input_row, output_buf, 0,
num_rows, cinfo->output_width);
}
/*
* Convert grayscale to RGB: just duplicate the graylevel three times.
* This is provided to support applications that don't want to cope
* with grayscale as a separate case.
*/
METHODDEF(void)
gray_rgb_convert (j_decompress_ptr cinfo,
JSAMPIMAGE input_buf, JDIMENSION input_row,
JSAMPARRAY output_buf, int num_rows)
{
register JSAMPROW inptr, outptr;
register JDIMENSION col;
JDIMENSION num_cols = cinfo->output_width;
while (--num_rows >= 0) {
inptr = input_buf[0][input_row++];
outptr = *output_buf++;
for (col = 0; col < num_cols; col++) {
/* We can dispense with GETJSAMPLE() here */
outptr[RGB_RED] = outptr[RGB_GREEN] = outptr[RGB_BLUE] = inptr[col];
outptr += RGB_PIXELSIZE;
}
}
}
/*
* Adobe-style YCCK->CMYK conversion.
* We convert YCbCr to R=1-C, G=1-M, and B=1-Y using the same
* conversion as above, while passing K (black) unchanged.
* We assume build_ycc_rgb_table has been called.
*/
METHODDEF(void)
ycck_cmyk_convert (j_decompress_ptr cinfo,
JSAMPIMAGE input_buf, JDIMENSION input_row,
JSAMPARRAY output_buf, int num_rows)
{
my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;
register int y, cb, cr;
register JSAMPROW outptr;
register JSAMPROW inptr0, inptr1, inptr2, inptr3;
register JDIMENSION col;
JDIMENSION num_cols = cinfo->output_width;
/* copy these pointers into registers if possible */
register JSAMPLE * range_limit = cinfo->sample_range_limit;
register int * Crrtab = cconvert->Cr_r_tab;
register int * Cbbtab = cconvert->Cb_b_tab;
register INT32 * Crgtab = cconvert->Cr_g_tab;
register INT32 * Cbgtab = cconvert->Cb_g_tab;
SHIFT_TEMPS
while (--num_rows >= 0) {
inptr0 = input_buf[0][input_row];
inptr1 = input_buf[1][input_row];
inptr2 = input_buf[2][input_row];
inptr3 = input_buf[3][input_row];
input_row++;
outptr = *output_buf++;
for (col = 0; col < num_cols; col++) {
y = GETJSAMPLE(inptr0[col]);
cb = GETJSAMPLE(inptr1[col]);
cr = GETJSAMPLE(inptr2[col]);
/* Range-limiting is essential due to noise introduced by DCT losses. */
outptr[0] = range_limit[MAXJSAMPLE - (y + Crrtab[cr])]; /* red */
outptr[1] = range_limit[MAXJSAMPLE - (y + /* green */
((int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr],
SCALEBITS)))];
outptr[2] = range_limit[MAXJSAMPLE - (y + Cbbtab[cb])]; /* blue */
/* K passes through unchanged */
outptr[3] = inptr3[col]; /* don't need GETJSAMPLE here */
outptr += 4;
}
}
}
/*
* Empty method for start_pass.
*/
METHODDEF(void)
start_pass_dcolor (j_decompress_ptr cinfo)
{
/* no work needed */
}
/*
* Module initialization routine for output colorspace conversion.
*/
GLOBAL(void)
jinit_color_deconverter (j_decompress_ptr cinfo)
{
my_cconvert_ptr cconvert;
int ci;
cconvert = (my_cconvert_ptr)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
SIZEOF(my_color_deconverter));
cinfo->cconvert = (struct jpeg_color_deconverter *) cconvert;
cconvert->pub.start_pass = start_pass_dcolor;
/* Make sure num_components agrees with jpeg_color_space */
switch (cinfo->jpeg_color_space) {
case JCS_GRAYSCALE:
if (cinfo->num_components != 1)
ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);
break;
case JCS_RGB:
case JCS_YCbCr:
if (cinfo->num_components != 3)
ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);
break;
case JCS_CMYK:
case JCS_YCCK:
if (cinfo->num_components != 4)
ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);
break;
default: /* JCS_UNKNOWN can be anything */
if (cinfo->num_components < 1)
ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);
break;
}
/* Set out_color_components and conversion method based on requested space.
* Also clear the component_needed flags for any unused components,
* so that earlier pipeline stages can avoid useless computation.
*/
switch (cinfo->out_color_space) {
case JCS_GRAYSCALE:
cinfo->out_color_components = 1;
if (cinfo->jpeg_color_space == JCS_GRAYSCALE ||
cinfo->jpeg_color_space == JCS_YCbCr) {
cconvert->pub.color_convert = grayscale_convert;
/* For color->grayscale conversion, only the Y (0) component is needed */
for (ci = 1; ci < cinfo->num_components; ci++)
cinfo->comp_info[ci].component_needed = FALSE;
} else
ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
break;
case JCS_RGB:
cinfo->out_color_components = RGB_PIXELSIZE;
if (cinfo->jpeg_color_space == JCS_YCbCr) {
cconvert->pub.color_convert = ycc_rgb_convert;
build_ycc_rgb_table(cinfo);
} else if (cinfo->jpeg_color_space == JCS_GRAYSCALE) {
cconvert->pub.color_convert = gray_rgb_convert;
} else if (cinfo->jpeg_color_space == JCS_RGB && RGB_PIXELSIZE == 3) {
cconvert->pub.color_convert = null_convert;
} else
ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
break;
case JCS_CMYK:
cinfo->out_color_components = 4;
if (cinfo->jpeg_color_space == JCS_YCCK) {
cconvert->pub.color_convert = ycck_cmyk_convert;
build_ycc_rgb_table(cinfo);
} else if (cinfo->jpeg_color_space == JCS_CMYK) {
cconvert->pub.color_convert = null_convert;
} else
ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
break;
default:
/* Permit null conversion to same output space */
if (cinfo->out_color_space == cinfo->jpeg_color_space) {
cinfo->out_color_components = cinfo->num_components;
cconvert->pub.color_convert = null_convert;
} else /* unsupported non-null conversion */
ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
break;
}
if (cinfo->quantize_colors)
cinfo->output_components = 1; /* single colormapped output component */
else
cinfo->output_components = cinfo->out_color_components;
}
dlib/external/libjpeg/jdct.h 0 → 100644
View file @ 7cd5f664
/*
* jdct.h
*
* Copyright (C) 1994-1996, Thomas G. Lane.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This include file contains common declarations for the forward and
* inverse DCT modules. These declarations are private to the DCT managers
* (jcdctmgr.c, jddctmgr.c) and the individual DCT algorithms.
* The individual DCT algorithms are kept in separate files to ease
* machine-dependent tuning (e.g., assembly coding).
*/
/*
* A forward DCT routine is given a pointer to a work area of type DCTELEM[];
* the DCT is to be performed in-place in that buffer. Type DCTELEM is int
* for 8-bit samples, INT32 for 12-bit samples. (NOTE: Floating-point DCT
* implementations use an array of type FAST_FLOAT, instead.)
* The DCT inputs are expected to be signed (range +-CENTERJSAMPLE).
* The DCT outputs are returned scaled up by a factor of 8; they therefore
* have a range of +-8K for 8-bit data, +-128K for 12-bit data. This
* convention improves accuracy in integer implementations and saves some
* work in floating-point ones.
* Quantization of the output coefficients is done by jcdctmgr.c.
*/
#if BITS_IN_JSAMPLE == 8
typedef int DCTELEM; /* 16 or 32 bits is fine */
#else
typedef INT32 DCTELEM; /* must have 32 bits */
#endif
typedef JMETHOD(void, forward_DCT_method_ptr, (DCTELEM * data));
typedef JMETHOD(void, float_DCT_method_ptr, (FAST_FLOAT * data));
/*
* An inverse DCT routine is given a pointer to the input JBLOCK and a pointer
* to an output sample array. The routine must dequantize the input data as
* well as perform the IDCT; for dequantization, it uses the multiplier table
* pointed to by compptr->dct_table. The output data is to be placed into the
* sample array starting at a specified column. (Any row offset needed will
* be applied to the array pointer before it is passed to the IDCT code.)
* Note that the number of samples emitted by the IDCT routine is
* DCT_scaled_size * DCT_scaled_size.
*/
/* typedef inverse_DCT_method_ptr is declared in jpegint.h */
/*
* Each IDCT routine has its own ideas about the best dct_table element type.
*/
typedef MULTIPLIER ISLOW_MULT_TYPE; /* short or int, whichever is faster */
#if BITS_IN_JSAMPLE == 8
typedef MULTIPLIER IFAST_MULT_TYPE; /* 16 bits is OK, use short if faster */
#define IFAST_SCALE_BITS 2 /* fractional bits in scale factors */
#else
typedef INT32 IFAST_MULT_TYPE; /* need 32 bits for scaled quantizers */
#define IFAST_SCALE_BITS 13 /* fractional bits in scale factors */
#endif
typedef FAST_FLOAT FLOAT_MULT_TYPE; /* preferred floating type */
/*
* Each IDCT routine is responsible for range-limiting its results and
* converting them to unsigned form (0..MAXJSAMPLE). The raw outputs could
* be quite far out of range if the input data is corrupt, so a bulletproof
* range-limiting step is required. We use a mask-and-table-lookup method
* to do the combined operations quickly. See the comments with
* prepare_range_limit_table (in jdmaster.c) for more info.
*/
#define IDCT_range_limit(cinfo) ((cinfo)->sample_range_limit + CENTERJSAMPLE)
#define RANGE_MASK (MAXJSAMPLE * 4 + 3) /* 2 bits wider than legal samples */
/* Short forms of external names for systems with brain-damaged linkers. */
#ifdef NEED_SHORT_EXTERNAL_NAMES
#define jpeg_fdct_islow jFDislow
#define jpeg_fdct_ifast jFDifast
#define jpeg_fdct_float jFDfloat
#define jpeg_idct_islow jRDislow
#define jpeg_idct_ifast jRDifast
#define jpeg_idct_float jRDfloat
#define jpeg_idct_4x4 jRD4x4
#define jpeg_idct_2x2 jRD2x2
#define jpeg_idct_1x1 jRD1x1
#endif /* NEED_SHORT_EXTERNAL_NAMES */
/* Extern declarations for the forward and inverse DCT routines. */
EXTERN(void) jpeg_fdct_islow JPP((DCTELEM * data));
EXTERN(void) jpeg_fdct_ifast JPP((DCTELEM * data));
EXTERN(void) jpeg_fdct_float JPP((FAST_FLOAT * data));
EXTERN(void) jpeg_idct_islow
JPP((j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block, JSAMPARRAY output_buf, JDIMENSION output_col));
EXTERN(void) jpeg_idct_ifast
JPP((j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block, JSAMPARRAY output_buf, JDIMENSION output_col));
EXTERN(void) jpeg_idct_float
JPP((j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block, JSAMPARRAY output_buf, JDIMENSION output_col));
EXTERN(void) jpeg_idct_4x4
JPP((j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block, JSAMPARRAY output_buf, JDIMENSION output_col));
EXTERN(void) jpeg_idct_2x2
JPP((j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block, JSAMPARRAY output_buf, JDIMENSION output_col));
EXTERN(void) jpeg_idct_1x1
JPP((j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block, JSAMPARRAY output_buf, JDIMENSION output_col));
/*
* Macros for handling fixed-point arithmetic; these are used by many
* but not all of the DCT/IDCT modules.
*
* All values are expected to be of type INT32.
* Fractional constants are scaled left by CONST_BITS bits.
* CONST_BITS is defined within each module using these macros,
* and may differ from one module to the next.
*/
#define ONE ((INT32) 1)
#define CONST_SCALE (ONE << CONST_BITS)
/* Convert a positive real constant to an integer scaled by CONST_SCALE.
* Caution: some C compilers fail to reduce "FIX(constant)" at compile time,
* thus causing a lot of useless floating-point operations at run time.
*/
#define FIX(x) ((INT32) ((x) * CONST_SCALE + 0.5))
/* Descale and correctly round an INT32 value that's scaled by N bits.
* We assume RIGHT_SHIFT rounds towards minus infinity, so adding
* the fudge factor is correct for either sign of X.
*/
#define DESCALE(x,n) RIGHT_SHIFT((x) + (ONE << ((n)-1)), n)
/* Multiply an INT32 variable by an INT32 constant to yield an INT32 result.
* This macro is used only when the two inputs will actually be no more than
* 16 bits wide, so that a 16x16->32 bit multiply can be used instead of a
* full 32x32 multiply. This provides a useful speedup on many machines.
* Unfortunately there is no way to specify a 16x16->32 multiply portably
* in C, but some C compilers will do the right thing if you provide the
* correct combination of casts.
*/
#ifdef SHORTxSHORT_32 /* may work if 'int' is 32 bits */
#define MULTIPLY16C16(var,const) (((INT16) (var)) * ((INT16) (const)))
#endif
#ifdef SHORTxLCONST_32 /* known to work with Microsoft C 6.0 */
#define MULTIPLY16C16(var,const) (((INT16) (var)) * ((INT32) (const)))
#endif
#ifndef MULTIPLY16C16 /* default definition */
#define MULTIPLY16C16(var,const) ((var) * (const))
#endif
/* Same except both inputs are variables. */
#ifdef SHORTxSHORT_32 /* may work if 'int' is 32 bits */
#define MULTIPLY16V16(var1,var2) (((INT16) (var1)) * ((INT16) (var2)))
#endif
#ifndef MULTIPLY16V16 /* default definition */
#define MULTIPLY16V16(var1,var2) ((var1) * (var2))
#endif
dlib/external/libjpeg/jddctmgr.cpp 0 → 100644
View file @ 7cd5f664
/*
* jddctmgr.c
*
* Copyright (C) 1994-1996, Thomas G. Lane.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file contains the inverse-DCT management logic.
* This code selects a particular IDCT implementation to be used,
* and it performs related housekeeping chores. No code in this file
* is executed per IDCT step, only during output pass setup.
*
* Note that the IDCT routines are responsible for performing coefficient
* dequantization as well as the IDCT proper. This module sets up the
* dequantization multiplier table needed by the IDCT routine.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
#include "jdct.h" /* Private declarations for DCT subsystem */
/*
* The decompressor input side (jdinput.c) saves away the appropriate
* quantization table for each component at the start of the first scan
* involving that component. (This is necessary in order to correctly
* decode files that reuse Q-table slots.)
* When we are ready to make an output pass, the saved Q-table is converted
* to a multiplier table that will actually be used by the IDCT routine.
* The multiplier table contents are IDCT-method-dependent. To support
* application changes in IDCT method between scans, we can remake the
* multiplier tables if necessary.
* In buffered-image mode, the first output pass may occur before any data
* has been seen for some components, and thus before their Q-tables have
* been saved away. To handle this case, multiplier tables are preset
* to zeroes; the result of the IDCT will be a neutral gray level.
*/
/* Private subobject for this module */
typedef struct {
struct jpeg_inverse_dct pub; /* public fields */
/* This array contains the IDCT method code that each multiplier table
* is currently set up for, or -1 if it's not yet set up.
* The actual multiplier tables are pointed to by dct_table in the
* per-component comp_info structures.
*/
int cur_method[MAX_COMPONENTS];
} my_idct_controller;
typedef my_idct_controller * my_idct_ptr;
/* Allocated multiplier tables: big enough for any supported variant */
typedef union {
ISLOW_MULT_TYPE islow_array[DCTSIZE2];
#ifdef DCT_IFAST_SUPPORTED
IFAST_MULT_TYPE ifast_array[DCTSIZE2];
#endif
#ifdef DCT_FLOAT_SUPPORTED
FLOAT_MULT_TYPE float_array[DCTSIZE2];
#endif
} multiplier_table;
/* The current scaled-IDCT routines require ISLOW-style multiplier tables,
* so be sure to compile that code if either ISLOW or SCALING is requested.
*/
#ifdef DCT_ISLOW_SUPPORTED
#define PROVIDE_ISLOW_TABLES
#else
#ifdef IDCT_SCALING_SUPPORTED
#define PROVIDE_ISLOW_TABLES
#endif
#endif
/*
* Prepare for an output pass.
* Here we select the proper IDCT routine for each component and build
* a matching multiplier table.
*/
METHODDEF(void)
start_pass (j_decompress_ptr cinfo)
{
my_idct_ptr idct = (my_idct_ptr) cinfo->idct;
int ci, i;
jpeg_component_info *compptr;
int method = 0;
inverse_DCT_method_ptr method_ptr = NULL;
JQUANT_TBL * qtbl;
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
/* Select the proper IDCT routine for this component's scaling */
switch (compptr->DCT_scaled_size) {
#ifdef IDCT_SCALING_SUPPORTED
case 1:
method_ptr = jpeg_idct_1x1;
method = JDCT_ISLOW; /* jidctred uses islow-style table */
break;
case 2:
method_ptr = jpeg_idct_2x2;
method = JDCT_ISLOW; /* jidctred uses islow-style table */
break;
case 4:
method_ptr = jpeg_idct_4x4;
method = JDCT_ISLOW; /* jidctred uses islow-style table */
break;
#endif
case DCTSIZE:
switch (cinfo->dct_method) {
#ifdef DCT_ISLOW_SUPPORTED
case JDCT_ISLOW:
method_ptr = jpeg_idct_islow;
method = JDCT_ISLOW;
break;
#endif
#ifdef DCT_IFAST_SUPPORTED
case JDCT_IFAST:
method_ptr = jpeg_idct_ifast;
method = JDCT_IFAST;
break;
#endif
#ifdef DCT_FLOAT_SUPPORTED
case JDCT_FLOAT:
method_ptr = jpeg_idct_float;
method = JDCT_FLOAT;
break;
#endif
default:
ERREXIT(cinfo, JERR_NOT_COMPILED);
break;
}
break;
default:
ERREXIT1(cinfo, JERR_BAD_DCTSIZE, compptr->DCT_scaled_size);
break;
}
idct->pub.inverse_DCT[ci] = method_ptr;
/* Create multiplier table from quant table.
* However, we can skip this if the component is uninteresting
* or if we already built the table. Also, if no quant table
* has yet been saved for the component, we leave the
* multiplier table all-zero; we'll be reading zeroes from the
* coefficient controller's buffer anyway.
*/
if (! compptr->component_needed || idct->cur_method[ci] == method)
continue;
qtbl = compptr->quant_table;
if (qtbl == NULL) /* happens if no data yet for component */
continue;
idct->cur_method[ci] = method;
switch (method) {
#ifdef PROVIDE_ISLOW_TABLES
case JDCT_ISLOW:
{
/* For LL&M IDCT method, multipliers are equal to raw quantization
* coefficients, but are stored as ints to ensure access efficiency.
*/
ISLOW_MULT_TYPE * ismtbl = (ISLOW_MULT_TYPE *) compptr->dct_table;
for (i = 0; i < DCTSIZE2; i++) {
ismtbl[i] = (ISLOW_MULT_TYPE) qtbl->quantval[i];
}
}
break;
#endif
#ifdef DCT_IFAST_SUPPORTED
case JDCT_IFAST:
{
/* For AA&N IDCT method, multipliers are equal to quantization
* coefficients scaled by scalefactor[row]*scalefactor[col], where
* scalefactor[0] = 1
* scalefactor[k] = cos(k*PI/16) * sqrt(2) for k=1..7
* For integer operation, the multiplier table is to be scaled by
* IFAST_SCALE_BITS.
*/
IFAST_MULT_TYPE * ifmtbl = (IFAST_MULT_TYPE *) compptr->dct_table;
#define CONST_BITS 14
static const INT16 aanscales[DCTSIZE2] = {
/* precomputed values scaled up by 14 bits */
16384, 22725, 21407, 19266, 16384, 12873, 8867, 4520,
22725, 31521, 29692, 26722, 22725, 17855, 12299, 6270,
21407, 29692, 27969, 25172, 21407, 16819, 11585, 5906,
19266, 26722, 25172, 22654, 19266, 15137, 10426, 5315,
16384, 22725, 21407, 19266, 16384, 12873, 8867, 4520,
12873, 17855, 16819, 15137, 12873, 10114, 6967, 3552,
8867, 12299, 11585, 10426, 8867, 6967, 4799, 2446,
4520, 6270, 5906, 5315, 4520, 3552, 2446, 1247
};
SHIFT_TEMPS
for (i = 0; i < DCTSIZE2; i++) {
ifmtbl[i] = (IFAST_MULT_TYPE)
DESCALE(MULTIPLY16V16((INT32) qtbl->quantval[i],
(INT32) aanscales[i]),
CONST_BITS-IFAST_SCALE_BITS);
}
}
break;
#endif
#ifdef DCT_FLOAT_SUPPORTED
case JDCT_FLOAT:
{
/* For float AA&N IDCT method, multipliers are equal to quantization
* coefficients scaled by scalefactor[row]*scalefactor[col], where
* scalefactor[0] = 1
* scalefactor[k] = cos(k*PI/16) * sqrt(2) for k=1..7
*/
FLOAT_MULT_TYPE * fmtbl = (FLOAT_MULT_TYPE *) compptr->dct_table;
int row, col;
static const double aanscalefactor[DCTSIZE] = {
1.0, 1.387039845, 1.306562965, 1.175875602,
1.0, 0.785694958, 0.541196100, 0.275899379
};
i = 0;
for (row = 0; row < DCTSIZE; row++) {
for (col = 0; col < DCTSIZE; col++) {
fmtbl[i] = (FLOAT_MULT_TYPE)
((double) qtbl->quantval[i] *
aanscalefactor[row] * aanscalefactor[col]);
i++;
}
}
}
break;
#endif
default:
ERREXIT(cinfo, JERR_NOT_COMPILED);
break;
}
}
}
/*
* Initialize IDCT manager.
*/
GLOBAL(void)
jinit_inverse_dct (j_decompress_ptr cinfo)
{
my_idct_ptr idct;
int ci;
jpeg_component_info *compptr;
idct = (my_idct_ptr)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
SIZEOF(my_idct_controller));
cinfo->idct = (struct jpeg_inverse_dct *) idct;
idct->pub.start_pass = start_pass;
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
/* Allocate and pre-zero a multiplier table for each component */
compptr->dct_table =
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
SIZEOF(multiplier_table));
MEMZERO(compptr->dct_table, SIZEOF(multiplier_table));
/* Mark multiplier table not yet set up for any method */
idct->cur_method[ci] = -1;
}
}
dlib/external/libjpeg/jdhuff.cpp 0 → 100644
View file @ 7cd5f664
/*
* jdhuff.c
*
* Copyright (C) 1991-1997, Thomas G. Lane.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file contains Huffman entropy decoding routines.
*
* Much of the complexity here has to do with supporting input suspension.
* If the data source module demands suspension, we want to be able to back
* up to the start of the current MCU. To do this, we copy state variables
* into local working storage, and update them back to the permanent
* storage only upon successful completion of an MCU.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
#include "jdhuff.h" /* Declarations shared with jdphuff.c */
/*
* Expanded entropy decoder object for Huffman decoding.
*
* The savable_state subrecord contains fields that change within an MCU,
* but must not be updated permanently until we complete the MCU.
*/
typedef struct {
int last_dc_val[MAX_COMPS_IN_SCAN]; /* last DC coef for each component */
} savable_state;
/* This macro is to work around compilers with missing or broken
* structure assignment. You'll need to fix this code if you have
* such a compiler and you change MAX_COMPS_IN_SCAN.
*/
#ifndef NO_STRUCT_ASSIGN
#define ASSIGN_STATE(dest,src) ((dest) = (src))
#else
#if MAX_COMPS_IN_SCAN == 4
#define ASSIGN_STATE(dest,src) \
((dest).last_dc_val[0] = (src).last_dc_val[0], \
(dest).last_dc_val[1] = (src).last_dc_val[1], \
(dest).last_dc_val[2] = (src).last_dc_val[2], \
(dest).last_dc_val[3] = (src).last_dc_val[3])
#endif
#endif
typedef struct {
struct jpeg_entropy_decoder pub; /* public fields */
/* These fields are loaded into local variables at start of each MCU.
* In case of suspension, we exit WITHOUT updating them.
*/
bitread_perm_state bitstate; /* Bit buffer at start of MCU */
savable_state saved; /* Other state at start of MCU */
/* These fields are NOT loaded into local working state. */
unsigned int restarts_to_go; /* MCUs left in this restart interval */
/* Pointers to derived tables (these workspaces have image lifespan) */
d_derived_tbl * dc_derived_tbls[NUM_HUFF_TBLS];
d_derived_tbl * ac_derived_tbls[NUM_HUFF_TBLS];
/* Precalculated info set up by start_pass for use in decode_mcu: */
/* Pointers to derived tables to be used for each block within an MCU */
d_derived_tbl * dc_cur_tbls[D_MAX_BLOCKS_IN_MCU];
d_derived_tbl * ac_cur_tbls[D_MAX_BLOCKS_IN_MCU];
/* Whether we care about the DC and AC coefficient values for each block */
boolean dc_needed[D_MAX_BLOCKS_IN_MCU];
boolean ac_needed[D_MAX_BLOCKS_IN_MCU];
} huff_entropy_decoder;
typedef huff_entropy_decoder * huff_entropy_ptr;
/*
* Initialize for a Huffman-compressed scan.
*/
METHODDEF(void)
start_pass_huff_decoder (j_decompress_ptr cinfo)
{
huff_entropy_ptr entropy = (huff_entropy_ptr) cinfo->entropy;
int ci, blkn, dctbl, actbl;
jpeg_component_info * compptr;
/* Check that the scan parameters Ss, Se, Ah/Al are OK for sequential JPEG.
* This ought to be an error condition, but we make it a warning because
* there are some baseline files out there with all zeroes in these bytes.
*/
if (cinfo->Ss != 0 || cinfo->Se != DCTSIZE2-1 ||
cinfo->Ah != 0 || cinfo->Al != 0)
WARNMS(cinfo, JWRN_NOT_SEQUENTIAL);
for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
compptr = cinfo->cur_comp_info[ci];
dctbl = compptr->dc_tbl_no;
actbl = compptr->ac_tbl_no;
/* Compute derived values for Huffman tables */
/* We may do this more than once for a table, but it's not expensive */
jpeg_make_d_derived_tbl(cinfo, TRUE, dctbl,
& entropy->dc_derived_tbls[dctbl]);
jpeg_make_d_derived_tbl(cinfo, FALSE, actbl,
& entropy->ac_derived_tbls[actbl]);
/* Initialize DC predictions to 0 */
entropy->saved.last_dc_val[ci] = 0;
}
/* Precalculate decoding info for each block in an MCU of this scan */
for (blkn = 0; blkn < cinfo->blocks_in_MCU; blkn++) {
ci = cinfo->MCU_membership[blkn];
compptr = cinfo->cur_comp_info[ci];
/* Precalculate which table to use for each block */
entropy->dc_cur_tbls[blkn] = entropy->dc_derived_tbls[compptr->dc_tbl_no];
entropy->ac_cur_tbls[blkn] = entropy->ac_derived_tbls[compptr->ac_tbl_no];
/* Decide whether we really care about the coefficient values */
if (compptr->component_needed) {
entropy->dc_needed[blkn] = TRUE;
/* we don't need the ACs if producing a 1/8th-size image */
entropy->ac_needed[blkn] = (compptr->DCT_scaled_size > 1);
} else {
entropy->dc_needed[blkn] = entropy->ac_needed[blkn] = FALSE;
}
}
/* Initialize bitread state variables */
entropy->bitstate.bits_left = 0;
entropy->bitstate.get_buffer = 0; /* unnecessary, but keeps Purify quiet */
entropy->pub.insufficient_data = FALSE;
/* Initialize restart counter */
entropy->restarts_to_go = cinfo->restart_interval;
}
/*
* Compute the derived values for a Huffman table.
* This routine also performs some validation checks on the table.
*
* Note this is also used by jdphuff.c.
*/
GLOBAL(void)
jpeg_make_d_derived_tbl (j_decompress_ptr cinfo, boolean isDC, int tblno,
d_derived_tbl ** pdtbl)
{
JHUFF_TBL *htbl;
d_derived_tbl *dtbl;
int p, i, l, si, numsymbols;
int lookbits, ctr;
char huffsize[257];
unsigned int huffcode[257];
unsigned int code;
/* Note that huffsize[] and huffcode[] are filled in code-length order,
* paralleling the order of the symbols themselves in htbl->huffval[].
*/
/* Find the input Huffman table */
if (tblno < 0 || tblno >= NUM_HUFF_TBLS)
ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, tblno);
htbl =
isDC ? cinfo->dc_huff_tbl_ptrs[tblno] : cinfo->ac_huff_tbl_ptrs[tblno];
if (htbl == NULL)
ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, tblno);
/* Allocate a workspace if we haven't already done so. */
if (*pdtbl == NULL)
*pdtbl = (d_derived_tbl *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
SIZEOF(d_derived_tbl));
dtbl = *pdtbl;
dtbl->pub = htbl; /* fill in back link */
/* Figure C.1: make table of Huffman code length for each symbol */
p = 0;
for (l = 1; l <= 16; l++) {
i = (int) htbl->bits[l];
if (i < 0 || p + i > 256) /* protect against table overrun */
ERREXIT(cinfo, JERR_BAD_HUFF_TABLE);
while (i--)
huffsize[p++] = (char) l;
}
huffsize[p] = 0;
numsymbols = p;
/* Figure C.2: generate the codes themselves */
/* We also validate that the counts represent a legal Huffman code tree. */
code = 0;
si = huffsize[0];
p = 0;
while (huffsize[p]) {
while (((int) huffsize[p]) == si) {
huffcode[p++] = code;
code++;
}
/* code is now 1 more than the last code used for codelength si; but
* it must still fit in si bits, since no code is allowed to be all ones.
*/
if (((INT32) code) >= (((INT32) 1) << si))
ERREXIT(cinfo, JERR_BAD_HUFF_TABLE);
code <<= 1;
si++;
}
/* Figure F.15: generate decoding tables for bit-sequential decoding */
p = 0;
for (l = 1; l <= 16; l++) {
if (htbl->bits[l]) {
/* valoffset[l] = huffval[] index of 1st symbol of code length l,
* minus the minimum code of length l
*/
dtbl->valoffset[l] = (INT32) p - (INT32) huffcode[p];
p += htbl->bits[l];
dtbl->maxcode[l] = huffcode[p-1]; /* maximum code of length l */
} else {
dtbl->maxcode[l] = -1; /* -1 if no codes of this length */
}
}
dtbl->maxcode[17] = 0xFFFFFL; /* ensures jpeg_huff_decode terminates */
/* Compute lookahead tables to speed up decoding.
* First we set all the table entries to 0, indicating "too long";
* then we iterate through the Huffman codes that are short enough and
* fill in all the entries that correspond to bit sequences starting
* with that code.
*/
MEMZERO(dtbl->look_nbits, SIZEOF(dtbl->look_nbits));
p = 0;
for (l = 1; l <= HUFF_LOOKAHEAD; l++) {
for (i = 1; i <= (int) htbl->bits[l]; i++, p++) {
/* l = current code's length, p = its index in huffcode[] & huffval[]. */
/* Generate left-justified code followed by all possible bit sequences */
lookbits = huffcode[p] << (HUFF_LOOKAHEAD-l);
for (ctr = 1 << (HUFF_LOOKAHEAD-l); ctr > 0; ctr--) {
dtbl->look_nbits[lookbits] = l;
dtbl->look_sym[lookbits] = htbl->huffval[p];
lookbits++;
}
}
}
/* Validate symbols as being reasonable.
* For AC tables, we make no check, but accept all byte values 0..255.
* For DC tables, we require the symbols to be in range 0..15.
* (Tighter bounds could be applied depending on the data depth and mode,
* but this is sufficient to ensure safe decoding.)
*/
if (isDC) {
for (i = 0; i < numsymbols; i++) {
int sym = htbl->huffval[i];
if (sym < 0 || sym > 15)
ERREXIT(cinfo, JERR_BAD_HUFF_TABLE);
}
}
}
/*
* Out-of-line code for bit fetching (shared with jdphuff.c).
* See jdhuff.h for info about usage.
* Note: current values of get_buffer and bits_left are passed as parameters,
* but are returned in the corresponding fields of the state struct.
*
* On most machines MIN_GET_BITS should be 25 to allow the full 32-bit width
* of get_buffer to be used. (On machines with wider words, an even larger
* buffer could be used.) However, on some machines 32-bit shifts are
* quite slow and take time proportional to the number of places shifted.
* (This is true with most PC compilers, for instance.) In this case it may
* be a win to set MIN_GET_BITS to the minimum value of 15. This reduces the
* average shift distance at the cost of more calls to jpeg_fill_bit_buffer.
*/
#ifdef SLOW_SHIFT_32
#define MIN_GET_BITS 15 /* minimum allowable value */
#else
#define MIN_GET_BITS (BIT_BUF_SIZE-7)
#endif
GLOBAL(boolean)
jpeg_fill_bit_buffer (bitread_working_state * state,
register bit_buf_type get_buffer, register int bits_left,
int nbits)
/* Load up the bit buffer to a depth of at least nbits */
{
/* Copy heavily used state fields into locals (hopefully registers) */
register const JOCTET * next_input_byte = state->next_input_byte;
register size_t bytes_in_buffer = state->bytes_in_buffer;
j_decompress_ptr cinfo = state->cinfo;
/* Attempt to load at least MIN_GET_BITS bits into get_buffer. */
/* (It is assumed that no request will be for more than that many bits.) */
/* We fail to do so only if we hit a marker or are forced to suspend. */
if (cinfo->unread_marker == 0) { /* cannot advance past a marker */
while (bits_left < MIN_GET_BITS) {
register int c;
/* Attempt to read a byte */
if (bytes_in_buffer == 0) {
if (! (*cinfo->src->fill_input_buffer) (cinfo))
return FALSE;
next_input_byte = cinfo->src->next_input_byte;
bytes_in_buffer = cinfo->src->bytes_in_buffer;
}
bytes_in_buffer--;
c = GETJOCTET(*next_input_byte++);
/* If it's 0xFF, check and discard stuffed zero byte */
if (c == 0xFF) {
/* Loop here to discard any padding FF's on terminating marker,
* so that we can save a valid unread_marker value. NOTE: we will
* accept multiple FF's followed by a 0 as meaning a single FF data
* byte. This data pattern is not valid according to the standard.
*/
do {
if (bytes_in_buffer == 0) {
if (! (*cinfo->src->fill_input_buffer) (cinfo))
return FALSE;
next_input_byte = cinfo->src->next_input_byte;
bytes_in_buffer = cinfo->src->bytes_in_buffer;
}
bytes_in_buffer--;
c = GETJOCTET(*next_input_byte++);
} while (c == 0xFF);
if (c == 0) {
/* Found FF/00, which represents an FF data byte */
c = 0xFF;
} else {
/* Oops, it's actually a marker indicating end of compressed data.
* Save the marker code for later use.
* Fine point: it might appear that we should save the marker into
* bitread working state, not straight into permanent state. But
* once we have hit a marker, we cannot need to suspend within the
* current MCU, because we will read no more bytes from the data
* source. So it is OK to update permanent state right away.
*/
cinfo->unread_marker = c;
/* See if we need to insert some fake zero bits. */
goto no_more_bytes;
}
}
/* OK, load c into get_buffer */
get_buffer = (get_buffer << 8) | c;
bits_left += 8;
} /* end while */
} else {
no_more_bytes:
/* We get here if we've read the marker that terminates the compressed
* data segment. There should be enough bits in the buffer register
* to satisfy the request; if so, no problem.
*/
if (nbits > bits_left) {
/* Uh-oh. Report corrupted data to user and stuff zeroes into
* the data stream, so that we can produce some kind of image.
* We use a nonvolatile flag to ensure that only one warning message
* appears per data segment.
*/
if (! cinfo->entropy->insufficient_data) {
WARNMS(cinfo, JWRN_HIT_MARKER);
cinfo->entropy->insufficient_data = TRUE;
}
/* Fill the buffer with zero bits */
get_buffer <<= MIN_GET_BITS - bits_left;
bits_left = MIN_GET_BITS;
}
}
/* Unload the local registers */
state->next_input_byte = next_input_byte;
state->bytes_in_buffer = bytes_in_buffer;
state->get_buffer = get_buffer;
state->bits_left = bits_left;
return TRUE;
}
/*
* Out-of-line code for Huffman code decoding.
* See jdhuff.h for info about usage.
*/
GLOBAL(int)
jpeg_huff_decode (bitread_working_state * state,
register bit_buf_type get_buffer, register int bits_left,
d_derived_tbl * htbl, int min_bits)
{
register int l = min_bits;
register INT32 code;
/* HUFF_DECODE has determined that the code is at least min_bits */
/* bits long, so fetch that many bits in one swoop. */
CHECK_BIT_BUFFER(*state, l, return -1);
code = GET_BITS(l);
/* Collect the rest of the Huffman code one bit at a time. */
/* This is per Figure F.16 in the JPEG spec. */
while (code > htbl->maxcode[l]) {
code <<= 1;
CHECK_BIT_BUFFER(*state, 1, return -1);
code |= GET_BITS(1);
l++;
}
/* Unload the local registers */
state->get_buffer = get_buffer;
state->bits_left = bits_left;
/* With garbage input we may reach the sentinel value l = 17. */
if (l > 16) {
WARNMS(state->cinfo, JWRN_HUFF_BAD_CODE);
return 0; /* fake a zero as the safest result */
}
return htbl->pub->huffval[ (int) (code + htbl->valoffset[l]) ];
}
/*
* Figure F.12: extend sign bit.
* On some machines, a shift and add will be faster than a table lookup.
*/
#ifdef AVOID_TABLES
#define HUFF_EXTEND(x,s) ((x) < (1<<((s)-1)) ? (x) + (((-1)<<(s)) + 1) : (x))
#else
#define HUFF_EXTEND(x,s) ((x) < extend_test[s] ? (x) + extend_offset[s] : (x))
static const int extend_test[16] = /* entry n is 2**(n-1) */
{ 0, 0x0001, 0x0002, 0x0004, 0x0008, 0x0010, 0x0020, 0x0040, 0x0080,
0x0100, 0x0200, 0x0400, 0x0800, 0x1000, 0x2000, 0x4000 };
static const int extend_offset[16] = /* entry n is (-1 << n) + 1 */
{ 0, ((-1)<<1) + 1, ((-1)<<2) + 1, ((-1)<<3) + 1, ((-1)<<4) + 1,
((-1)<<5) + 1, ((-1)<<6) + 1, ((-1)<<7) + 1, ((-1)<<8) + 1,
((-1)<<9) + 1, ((-1)<<10) + 1, ((-1)<<11) + 1, ((-1)<<12) + 1,
((-1)<<13) + 1, ((-1)<<14) + 1, ((-1)<<15) + 1 };
#endif /* AVOID_TABLES */
/*
* Check for a restart marker & resynchronize decoder.
* Returns FALSE if must suspend.
*/
LOCAL(boolean)
process_restart (j_decompress_ptr cinfo)
{
huff_entropy_ptr entropy = (huff_entropy_ptr) cinfo->entropy;
int ci;
/* Throw away any unused bits remaining in bit buffer; */
/* include any full bytes in next_marker's count of discarded bytes */
cinfo->marker->discarded_bytes += entropy->bitstate.bits_left / 8;
entropy->bitstate.bits_left = 0;
/* Advance past the RSTn marker */
if (! (*cinfo->marker->read_restart_marker) (cinfo))
return FALSE;
/* Re-initialize DC predictions to 0 */
for (ci = 0; ci < cinfo->comps_in_scan; ci++)
entropy->saved.last_dc_val[ci] = 0;
/* Reset restart counter */
entropy->restarts_to_go = cinfo->restart_interval;
/* Reset out-of-data flag, unless read_restart_marker left us smack up
* against a marker. In that case we will end up treating the next data
* segment as empty, and we can avoid producing bogus output pixels by
* leaving the flag set.
*/
if (cinfo->unread_marker == 0)
entropy->pub.insufficient_data = FALSE;
return TRUE;
}
/*
* Decode and return one MCU's worth of Huffman-compressed coefficients.
* The coefficients are reordered from zigzag order into natural array order,
* but are not dequantized.
*
* The i'th block of the MCU is stored into the block pointed to by
* MCU_data[i]. WE ASSUME THIS AREA HAS BEEN ZEROED BY THE CALLER.
* (Wholesale zeroing is usually a little faster than retail...)
*
* Returns FALSE if data source requested suspension. In that case no
* changes have been made to permanent state. (Exception: some output
* coefficients may already have been assigned. This is harmless for
* this module, since we'll just re-assign them on the next call.)
*/
METHODDEF(boolean)
decode_mcu (j_decompress_ptr cinfo, JBLOCKROW *MCU_data)
{
huff_entropy_ptr entropy = (huff_entropy_ptr) cinfo->entropy;
int blkn;
BITREAD_STATE_VARS;
savable_state state;
/* Process restart marker if needed; may have to suspend */
if (cinfo->restart_interval) {
if (entropy->restarts_to_go == 0)
if (! process_restart(cinfo))
return FALSE;
}
/* If we've run out of data, just leave the MCU set to zeroes.
* This way, we return uniform gray for the remainder of the segment.
*/
if (! entropy->pub.insufficient_data) {
/* Load up working state */
BITREAD_LOAD_STATE(cinfo,entropy->bitstate);
ASSIGN_STATE(state, entropy->saved);
/* Outer loop handles each block in the MCU */
for (blkn = 0; blkn < cinfo->blocks_in_MCU; blkn++) {
JBLOCKROW block = MCU_data[blkn];
d_derived_tbl * dctbl = entropy->dc_cur_tbls[blkn];
d_derived_tbl * actbl = entropy->ac_cur_tbls[blkn];
register int s, k, r;
/* Decode a single block's worth of coefficients */
/* Section F.2.2.1: decode the DC coefficient difference */
HUFF_DECODE(s, br_state, dctbl, return FALSE, label1);
if (s) {
CHECK_BIT_BUFFER(br_state, s, return FALSE);
r = GET_BITS(s);
s = HUFF_EXTEND(r, s);
}
if (entropy->dc_needed[blkn]) {
/* Convert DC difference to actual value, update last_dc_val */
int ci = cinfo->MCU_membership[blkn];
s += state.last_dc_val[ci];
state.last_dc_val[ci] = s;
/* Output the DC coefficient (assumes jpeg_natural_order[0] = 0) */
(*block)[0] = (JCOEF) s;
}
if (entropy->ac_needed[blkn]) {
/* Section F.2.2.2: decode the AC coefficients */
/* Since zeroes are skipped, output area must be cleared beforehand */
for (k = 1; k < DCTSIZE2; k++) {
HUFF_DECODE(s, br_state, actbl, return FALSE, label2);
r = s >> 4;
s &= 15;
if (s) {
k += r;
CHECK_BIT_BUFFER(br_state, s, return FALSE);
r = GET_BITS(s);
s = HUFF_EXTEND(r, s);
/* Output coefficient in natural (dezigzagged) order.
* Note: the extra entries in jpeg_natural_order[] will save us
* if k >= DCTSIZE2, which could happen if the data is corrupted.
*/
(*block)[jpeg_natural_order[k]] = (JCOEF) s;
} else {
if (r != 15)
break;
k += 15;
}
}
} else {
/* Section F.2.2.2: decode the AC coefficients */
/* In this path we just discard the values */
for (k = 1; k < DCTSIZE2; k++) {
HUFF_DECODE(s, br_state, actbl, return FALSE, label3);
r = s >> 4;
s &= 15;
if (s) {
k += r;
CHECK_BIT_BUFFER(br_state, s, return FALSE);
DROP_BITS(s);
} else {
if (r != 15)
break;
k += 15;
}
}
}
}
/* Completed MCU, so update state */
BITREAD_SAVE_STATE(cinfo,entropy->bitstate);
ASSIGN_STATE(entropy->saved, state);
}
/* Account for restart interval (no-op if not using restarts) */
entropy->restarts_to_go--;
return TRUE;
}
/*
* Module initialization routine for Huffman entropy decoding.
*/
GLOBAL(void)
jinit_huff_decoder (j_decompress_ptr cinfo)
{
huff_entropy_ptr entropy;
int i;
entropy = (huff_entropy_ptr)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
SIZEOF(huff_entropy_decoder));
cinfo->entropy = (struct jpeg_entropy_decoder *) entropy;
entropy->pub.start_pass = start_pass_huff_decoder;
entropy->pub.decode_mcu = decode_mcu;
/* Mark tables unallocated */
for (i = 0; i < NUM_HUFF_TBLS; i++) {
entropy->dc_derived_tbls[i] = entropy->ac_derived_tbls[i] = NULL;
}
}
dlib/external/libjpeg/jdhuff.h 0 → 100644
View file @ 7cd5f664
/*
* jdhuff.h
*
* Copyright (C) 1991-1997, Thomas G. Lane.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file contains declarations for Huffman entropy decoding routines
* that are shared between the sequential decoder (jdhuff.c) and the
* progressive decoder (jdphuff.c). No other modules need to see these.
*/
/* Short forms of external names for systems with brain-damaged linkers. */
#ifdef NEED_SHORT_EXTERNAL_NAMES
#define jpeg_make_d_derived_tbl jMkDDerived
#define jpeg_fill_bit_buffer jFilBitBuf
#define jpeg_huff_decode jHufDecode
#endif /* NEED_SHORT_EXTERNAL_NAMES */
/* Derived data constructed for each Huffman table */
#define HUFF_LOOKAHEAD 8 /* # of bits of lookahead */
typedef struct {
/* Basic tables: (element [0] of each array is unused) */
INT32 maxcode[18]; /* largest code of length k (-1 if none) */
/* (maxcode[17] is a sentinel to ensure jpeg_huff_decode terminates) */
INT32 valoffset[17]; /* huffval[] offset for codes of length k */
/* valoffset[k] = huffval[] index of 1st symbol of code length k, less
* the smallest code of length k; so given a code of length k, the
* corresponding symbol is huffval[code + valoffset[k]]
*/
/* Link to public Huffman table (needed only in jpeg_huff_decode) */
JHUFF_TBL *pub;
/* Lookahead tables: indexed by the next HUFF_LOOKAHEAD bits of
* the input data stream. If the next Huffman code is no more
* than HUFF_LOOKAHEAD bits long, we can obtain its length and
* the corresponding symbol directly from these tables.
*/
int look_nbits[1<<HUFF_LOOKAHEAD]; /* # bits, or 0 if too long */
UINT8 look_sym[1<<HUFF_LOOKAHEAD]; /* symbol, or unused */
} d_derived_tbl;
/* Expand a Huffman table definition into the derived format */
EXTERN(void) jpeg_make_d_derived_tbl
JPP((j_decompress_ptr cinfo, boolean isDC, int tblno,
d_derived_tbl ** pdtbl));
/*
* Fetching the next N bits from the input stream is a time-critical operation
* for the Huffman decoders. We implement it with a combination of inline
* macros and out-of-line subroutines. Note that N (the number of bits
* demanded at one time) never exceeds 15 for JPEG use.
*
* We read source bytes into get_buffer and dole out bits as needed.
* If get_buffer already contains enough bits, they are fetched in-line
* by the macros CHECK_BIT_BUFFER and GET_BITS. When there aren't enough
* bits, jpeg_fill_bit_buffer is called; it will attempt to fill get_buffer
* as full as possible (not just to the number of bits needed; this
* prefetching reduces the overhead cost of calling jpeg_fill_bit_buffer).
* Note that jpeg_fill_bit_buffer may return FALSE to indicate suspension.
* On TRUE return, jpeg_fill_bit_buffer guarantees that get_buffer contains
* at least the requested number of bits --- dummy zeroes are inserted if
* necessary.
*/
typedef INT32 bit_buf_type; /* type of bit-extraction buffer */
#define BIT_BUF_SIZE 32 /* size of buffer in bits */
/* If long is > 32 bits on your machine, and shifting/masking longs is
* reasonably fast, making bit_buf_type be long and setting BIT_BUF_SIZE
* appropriately should be a win. Unfortunately we can't define the size
* with something like #define BIT_BUF_SIZE (sizeof(bit_buf_type)*8)
* because not all machines measure sizeof in 8-bit bytes.
*/
typedef struct { /* Bitreading state saved across MCUs */
bit_buf_type get_buffer; /* current bit-extraction buffer */
int bits_left; /* # of unused bits in it */
} bitread_perm_state;
typedef struct { /* Bitreading working state within an MCU */
/* Current data source location */
/* We need a copy, rather than munging the original, in case of suspension */
const JOCTET * next_input_byte; /* => next byte to read from source */
size_t bytes_in_buffer; /* # of bytes remaining in source buffer */
/* Bit input buffer --- note these values are kept in register variables,
* not in this struct, inside the inner loops.
*/
bit_buf_type get_buffer; /* current bit-extraction buffer */
int bits_left; /* # of unused bits in it */
/* Pointer needed by jpeg_fill_bit_buffer. */
j_decompress_ptr cinfo; /* back link to decompress master record */
} bitread_working_state;
/* Macros to declare and load/save bitread local variables. */
#define BITREAD_STATE_VARS \
register bit_buf_type get_buffer; \
register int bits_left; \
bitread_working_state br_state
#define BITREAD_LOAD_STATE(cinfop,permstate) \
br_state.cinfo = cinfop; \
br_state.next_input_byte = cinfop->src->next_input_byte; \
br_state.bytes_in_buffer = cinfop->src->bytes_in_buffer; \
get_buffer = permstate.get_buffer; \
bits_left = permstate.bits_left;
#define BITREAD_SAVE_STATE(cinfop,permstate) \
cinfop->src->next_input_byte = br_state.next_input_byte; \
cinfop->src->bytes_in_buffer = br_state.bytes_in_buffer; \
permstate.get_buffer = get_buffer; \
permstate.bits_left = bits_left
/*
* These macros provide the in-line portion of bit fetching.
* Use CHECK_BIT_BUFFER to ensure there are N bits in get_buffer
* before using GET_BITS, PEEK_BITS, or DROP_BITS.
* The variables get_buffer and bits_left are assumed to be locals,
* but the state struct might not be (jpeg_huff_decode needs this).
* CHECK_BIT_BUFFER(state,n,action);
* Ensure there are N bits in get_buffer; if suspend, take action.
* val = GET_BITS(n);
* Fetch next N bits.
* val = PEEK_BITS(n);
* Fetch next N bits without removing them from the buffer.
* DROP_BITS(n);
* Discard next N bits.
* The value N should be a simple variable, not an expression, because it
* is evaluated multiple times.
*/
#define CHECK_BIT_BUFFER(state,nbits,action) \
{ if (bits_left < (nbits)) { \
if (! jpeg_fill_bit_buffer(&(state),get_buffer,bits_left,nbits)) \
{ action; } \
get_buffer = (state).get_buffer; bits_left = (state).bits_left; } }
#define GET_BITS(nbits) \
(((int) (get_buffer >> (bits_left -= (nbits)))) & ((1<<(nbits))-1))
#define PEEK_BITS(nbits) \
(((int) (get_buffer >> (bits_left - (nbits)))) & ((1<<(nbits))-1))
#define DROP_BITS(nbits) \
(bits_left -= (nbits))
/* Load up the bit buffer to a depth of at least nbits */
EXTERN(boolean) jpeg_fill_bit_buffer
JPP((bitread_working_state * state, register bit_buf_type get_buffer,
register int bits_left, int nbits));
/*
* Code for extracting next Huffman-coded symbol from input bit stream.
* Again, this is time-critical and we make the main paths be macros.
*
* We use a lookahead table to process codes of up to HUFF_LOOKAHEAD bits
* without looping. Usually, more than 95% of the Huffman codes will be 8
* or fewer bits long. The few overlength codes are handled with a loop,
* which need not be inline code.
*
* Notes about the HUFF_DECODE macro:
* 1. Near the end of the data segment, we may fail to get enough bits
* for a lookahead. In that case, we do it the hard way.
* 2. If the lookahead table contains no entry, the next code must be
* more than HUFF_LOOKAHEAD bits long.
* 3. jpeg_huff_decode returns -1 if forced to suspend.
*/
#define HUFF_DECODE(result,state,htbl,failaction,slowlabel) \
{ register int nb, look; \
if (bits_left < HUFF_LOOKAHEAD) { \
if (! jpeg_fill_bit_buffer(&state,get_buffer,bits_left, 0)) {failaction;} \
get_buffer = state.get_buffer; bits_left = state.bits_left; \
if (bits_left < HUFF_LOOKAHEAD) { \
nb = 1; goto slowlabel; \
} \
} \
look = PEEK_BITS(HUFF_LOOKAHEAD); \
if ((nb = htbl->look_nbits[look]) != 0) { \
DROP_BITS(nb); \
result = htbl->look_sym[look]; \
} else { \
nb = HUFF_LOOKAHEAD+1; \
slowlabel: \
if ((result=jpeg_huff_decode(&state,get_buffer,bits_left,htbl,nb)) < 0) \
{ failaction; } \
get_buffer = state.get_buffer; bits_left = state.bits_left; \
} \
}
/* Out-of-line case for Huffman code fetching */
EXTERN(int) jpeg_huff_decode
JPP((bitread_working_state * state, register bit_buf_type get_buffer,
register int bits_left, d_derived_tbl * htbl, int min_bits));
dlib/external/libjpeg/jdinput.cpp 0 → 100644
View file @ 7cd5f664
/*
* jdinput.c
*
* Copyright (C) 1991-1997, Thomas G. Lane.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file contains input control logic for the JPEG decompressor.
* These routines are concerned with controlling the decompressor's input
* processing (marker reading and coefficient decoding). The actual input
* reading is done in jdmarker.c, jdhuff.c, and jdphuff.c.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
/* Private state */
typedef struct {
struct jpeg_input_controller pub; /* public fields */
boolean inheaders; /* TRUE until first SOS is reached */
} my_input_controller;
typedef my_input_controller * my_inputctl_ptr;
/* Forward declarations */
METHODDEF(int) consume_markers JPP((j_decompress_ptr cinfo));
/*
* Routines to calculate various quantities related to the size of the image.
*/
LOCAL(void)
initial_setup (j_decompress_ptr cinfo)
/* Called once, when first SOS marker is reached */
{
int ci;
jpeg_component_info *compptr;
/* Make sure image isn't bigger than I can handle */
if ((long) cinfo->image_height > (long) JPEG_MAX_DIMENSION ||
(long) cinfo->image_width > (long) JPEG_MAX_DIMENSION)
ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) JPEG_MAX_DIMENSION);
/* For now, precision must match compiled-in value... */
if (cinfo->data_precision != BITS_IN_JSAMPLE)
ERREXIT1(cinfo, JERR_BAD_PRECISION, cinfo->data_precision);
/* Check that number of components won't exceed internal array sizes */
if (cinfo->num_components > MAX_COMPONENTS)
ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,
MAX_COMPONENTS);
/* Compute maximum sampling factors; check factor validity */
cinfo->max_h_samp_factor = 1;
cinfo->max_v_samp_factor = 1;
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
if (compptr->h_samp_factor<=0 || compptr->h_samp_factor>MAX_SAMP_FACTOR ||
compptr->v_samp_factor<=0 || compptr->v_samp_factor>MAX_SAMP_FACTOR)
ERREXIT(cinfo, JERR_BAD_SAMPLING);
cinfo->max_h_samp_factor = MAX(cinfo->max_h_samp_factor,
compptr->h_samp_factor);
cinfo->max_v_samp_factor = MAX(cinfo->max_v_samp_factor,
compptr->v_samp_factor);
}
/* We initialize DCT_scaled_size and min_DCT_scaled_size to DCTSIZE.
* In the full decompressor, this will be overridden by jdmaster.c;
* but in the transcoder, jdmaster.c is not used, so we must do it here.
*/
cinfo->min_DCT_scaled_size = DCTSIZE;
/* Compute dimensions of components */
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
compptr->DCT_scaled_size = DCTSIZE;
/* Size in DCT blocks */
compptr->width_in_blocks = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * (long) compptr->h_samp_factor,
(long) (cinfo->max_h_samp_factor * DCTSIZE));
compptr->height_in_blocks = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * (long) compptr->v_samp_factor,
(long) (cinfo->max_v_samp_factor * DCTSIZE));
/* downsampled_width and downsampled_height will also be overridden by
* jdmaster.c if we are doing full decompression. The transcoder library
* doesn't use these values, but the calling application might.
*/
/* Size in samples */
compptr->downsampled_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * (long) compptr->h_samp_factor,
(long) cinfo->max_h_samp_factor);
compptr->downsampled_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height * (long) compptr->v_samp_factor,
(long) cinfo->max_v_samp_factor);
/* Mark component needed, until color conversion says otherwise */
compptr->component_needed = TRUE;
/* Mark no quantization table yet saved for component */
compptr->quant_table = NULL;
}
/* Compute number of fully interleaved MCU rows. */
cinfo->total_iMCU_rows = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height,
(long) (cinfo->max_v_samp_factor*DCTSIZE));
/* Decide whether file contains multiple scans */
if (cinfo->comps_in_scan < cinfo->num_components || cinfo->progressive_mode)
cinfo->inputctl->has_multiple_scans = TRUE;
else
cinfo->inputctl->has_multiple_scans = FALSE;
}
LOCAL(void)
per_scan_setup (j_decompress_ptr cinfo)
/* Do computations that are needed before processing a JPEG scan */
/* cinfo->comps_in_scan and cinfo->cur_comp_info[] were set from SOS marker */
{
int ci, mcublks, tmp;
jpeg_component_info *compptr;
if (cinfo->comps_in_scan == 1) {
/* Noninterleaved (single-component) scan */
compptr = cinfo->cur_comp_info[0];
/* Overall image size in MCUs */
cinfo->MCUs_per_row = compptr->width_in_blocks;
cinfo->MCU_rows_in_scan = compptr->height_in_blocks;
/* For noninterleaved scan, always one block per MCU */
compptr->MCU_width = 1;
compptr->MCU_height = 1;
compptr->MCU_blocks = 1;
compptr->MCU_sample_width = compptr->DCT_scaled_size;
compptr->last_col_width = 1;
/* For noninterleaved scans, it is convenient to define last_row_height
* as the number of block rows present in the last iMCU row.
*/
tmp = (int) (compptr->height_in_blocks % compptr->v_samp_factor);
if (tmp == 0) tmp = compptr->v_samp_factor;
compptr->last_row_height = tmp;
/* Prepare array describing MCU composition */
cinfo->blocks_in_MCU = 1;
cinfo->MCU_membership[0] = 0;
} else {
/* Interleaved (multi-component) scan */
if (cinfo->comps_in_scan <= 0 || cinfo->comps_in_scan > MAX_COMPS_IN_SCAN)
ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->comps_in_scan,
MAX_COMPS_IN_SCAN);
/* Overall image size in MCUs */
cinfo->MCUs_per_row = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width,
(long) (cinfo->max_h_samp_factor*DCTSIZE));
cinfo->MCU_rows_in_scan = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height,
(long) (cinfo->max_v_samp_factor*DCTSIZE));
cinfo->blocks_in_MCU = 0;
for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
compptr = cinfo->cur_comp_info[ci];
/* Sampling factors give # of blocks of component in each MCU */
compptr->MCU_width = compptr->h_samp_factor;
compptr->MCU_height = compptr->v_samp_factor;
compptr->MCU_blocks = compptr->MCU_width * compptr->MCU_height;
compptr->MCU_sample_width = compptr->MCU_width * compptr->DCT_scaled_size;
/* Figure number of non-dummy blocks in last MCU column & row */
tmp = (int) (compptr->width_in_blocks % compptr->MCU_width);
if (tmp == 0) tmp = compptr->MCU_width;
compptr->last_col_width = tmp;
tmp = (int) (compptr->height_in_blocks % compptr->MCU_height);
if (tmp == 0) tmp = compptr->MCU_height;
compptr->last_row_height = tmp;
/* Prepare array describing MCU composition */
mcublks = compptr->MCU_blocks;
if (cinfo->blocks_in_MCU + mcublks > D_MAX_BLOCKS_IN_MCU)
ERREXIT(cinfo, JERR_BAD_MCU_SIZE);
while (mcublks-- > 0) {
cinfo->MCU_membership[cinfo->blocks_in_MCU++] = ci;
}
}
}
}
/*
* Save away a copy of the Q-table referenced by each component present
* in the current scan, unless already saved during a prior scan.
*
* In a multiple-scan JPEG file, the encoder could assign different components
* the same Q-table slot number, but change table definitions between scans
* so that each component uses a different Q-table. (The IJG encoder is not
* currently capable of doing this, but other encoders might.) Since we want
* to be able to dequantize all the components at the end of the file, this
* means that we have to save away the table actually used for each component.
* We do this by copying the table at the start of the first scan containing
* the component.
* The JPEG spec prohibits the encoder from changing the contents of a Q-table
* slot between scans of a component using that slot. If the encoder does so
* anyway, this decoder will simply use the Q-table values that were current
* at the start of the first scan for the component.
*
* The decompressor output side looks only at the saved quant tables,
* not at the current Q-table slots.
*/
LOCAL(void)
latch_quant_tables (j_decompress_ptr cinfo)
{
int ci, qtblno;
jpeg_component_info *compptr;
JQUANT_TBL * qtbl;
for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
compptr = cinfo->cur_comp_info[ci];
/* No work if we already saved Q-table for this component */
if (compptr->quant_table != NULL)
continue;
/* Make sure specified quantization table is present */
qtblno = compptr->quant_tbl_no;
if (qtblno < 0 || qtblno >= NUM_QUANT_TBLS ||
cinfo->quant_tbl_ptrs[qtblno] == NULL)
ERREXIT1(cinfo, JERR_NO_QUANT_TABLE, qtblno);
/* OK, save away the quantization table */
qtbl = (JQUANT_TBL *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
SIZEOF(JQUANT_TBL));
MEMCOPY(qtbl, cinfo->quant_tbl_ptrs[qtblno], SIZEOF(JQUANT_TBL));
compptr->quant_table = qtbl;
}
}
/*
* Initialize the input modules to read a scan of compressed data.
* The first call to this is done by jdmaster.c after initializing
* the entire decompressor (during jpeg_start_decompress).
* Subsequent calls come from consume_markers, below.
*/
METHODDEF(void)
start_input_pass (j_decompress_ptr cinfo)
{
per_scan_setup(cinfo);
latch_quant_tables(cinfo);
(*cinfo->entropy->start_pass) (cinfo);
(*cinfo->coef->start_input_pass) (cinfo);
cinfo->inputctl->consume_input = cinfo->coef->consume_data;
}
/*
* Finish up after inputting a compressed-data scan.
* This is called by the coefficient controller after it's read all
* the expected data of the scan.
*/
METHODDEF(void)
finish_input_pass (j_decompress_ptr cinfo)
{
cinfo->inputctl->consume_input = consume_markers;
}
/*
* Read JPEG markers before, between, or after compressed-data scans.
* Change state as necessary when a new scan is reached.
* Return value is JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI.
*
* The consume_input method pointer points either here or to the
* coefficient controller's consume_data routine, depending on whether
* we are reading a compressed data segment or inter-segment markers.
*/
METHODDEF(int)
consume_markers (j_decompress_ptr cinfo)
{
my_inputctl_ptr inputctl = (my_inputctl_ptr) cinfo->inputctl;
int val;
if (inputctl->pub.eoi_reached) /* After hitting EOI, read no further */
return JPEG_REACHED_EOI;
val = (*cinfo->marker->read_markers) (cinfo);
switch (val) {
case JPEG_REACHED_SOS: /* Found SOS */
if (inputctl->inheaders) { /* 1st SOS */
initial_setup(cinfo);
inputctl->inheaders = FALSE;
/* Note: start_input_pass must be called by jdmaster.c
* before any more input can be consumed. jdapimin.c is
* responsible for enforcing this sequencing.
*/
} else { /* 2nd or later SOS marker */
if (! inputctl->pub.has_multiple_scans)
ERREXIT(cinfo, JERR_EOI_EXPECTED); /* Oops, I wasn't expecting this! */
start_input_pass(cinfo);
}
break;
case JPEG_REACHED_EOI: /* Found EOI */
inputctl->pub.eoi_reached = TRUE;
if (inputctl->inheaders) { /* Tables-only datastream, apparently */
if (cinfo->marker->saw_SOF)
ERREXIT(cinfo, JERR_SOF_NO_SOS);
} else {
/* Prevent infinite loop in coef ctlr's decompress_data routine
* if user set output_scan_number larger than number of scans.
*/
if (cinfo->output_scan_number > cinfo->input_scan_number)
cinfo->output_scan_number = cinfo->input_scan_number;
}
break;
case JPEG_SUSPENDED:
break;
}
return val;
}
/*
* Reset state to begin a fresh datastream.
*/
METHODDEF(void)
reset_input_controller (j_decompress_ptr cinfo)
{
my_inputctl_ptr inputctl = (my_inputctl_ptr) cinfo->inputctl;
inputctl->pub.consume_input = consume_markers;
inputctl->pub.has_multiple_scans = FALSE; /* "unknown" would be better */
inputctl->pub.eoi_reached = FALSE;
inputctl->inheaders = TRUE;
/* Reset other modules */
(*cinfo->err->reset_error_mgr) ((j_common_ptr) cinfo);
(*cinfo->marker->reset_marker_reader) (cinfo);
/* Reset progression state -- would be cleaner if entropy decoder did this */
cinfo->coef_bits = NULL;
}
/*
* Initialize the input controller module.
* This is called only once, when the decompression object is created.
*/
GLOBAL(void)
jinit_input_controller (j_decompress_ptr cinfo)
{
my_inputctl_ptr inputctl;
/* Create subobject in permanent pool */
inputctl = (my_inputctl_ptr)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
SIZEOF(my_input_controller));
cinfo->inputctl = (struct jpeg_input_controller *) inputctl;
/* Initialize method pointers */
inputctl->pub.consume_input = consume_markers;
inputctl->pub.reset_input_controller = reset_input_controller;
inputctl->pub.start_input_pass = start_input_pass;
inputctl->pub.finish_input_pass = finish_input_pass;
/* Initialize state: can't use reset_input_controller since we don't
* want to try to reset other modules yet.
*/
inputctl->pub.has_multiple_scans = FALSE; /* "unknown" would be better */
inputctl->pub.eoi_reached = FALSE;
inputctl->inheaders = TRUE;
}
dlib/external/libjpeg/jdmainct.cpp 0 → 100644
View file @ 7cd5f664
/*
* jdmainct.c
*
* Copyright (C) 1994-1996, Thomas G. Lane.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file contains the main buffer controller for decompression.
* The main buffer lies between the JPEG decompressor proper and the
* post-processor; it holds downsampled data in the JPEG colorspace.
*
* Note that this code is bypassed in raw-data mode, since the application
* supplies the equivalent of the main buffer in that case.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
/*
* In the current system design, the main buffer need never be a full-image
* buffer; any full-height buffers will be found inside the coefficient or
* postprocessing controllers. Nonetheless, the main controller is not
* trivial. Its responsibility is to provide context rows for upsampling/
* rescaling, and doing this in an efficient fashion is a bit tricky.
*
* Postprocessor input data is counted in "row groups". A row group
* is defined to be (v_samp_factor * DCT_scaled_size / min_DCT_scaled_size)
* sample rows of each component. (We require DCT_scaled_size values to be
* chosen such that these numbers are integers. In practice DCT_scaled_size
* values will likely be powers of two, so we actually have the stronger
* condition that DCT_scaled_size / min_DCT_scaled_size is an integer.)
* Upsampling will typically produce max_v_samp_factor pixel rows from each
* row group (times any additional scale factor that the upsampler is
* applying).
*
* The coefficient controller will deliver data to us one iMCU row at a time;
* each iMCU row contains v_samp_factor * DCT_scaled_size sample rows, or
* exactly min_DCT_scaled_size row groups. (This amount of data corresponds
* to one row of MCUs when the image is fully interleaved.) Note that the
* number of sample rows varies across components, but the number of row
* groups does not. Some garbage sample rows may be included in the last iMCU
* row at the bottom of the image.
*
* Depending on the vertical scaling algorithm used, the upsampler may need
* access to the sample row(s) above and below its current input row group.
* The upsampler is required to set need_context_rows TRUE at global selection
* time if so. When need_context_rows is FALSE, this controller can simply
* obtain one iMCU row at a time from the coefficient controller and dole it
* out as row groups to the postprocessor.
*
* When need_context_rows is TRUE, this controller guarantees that the buffer
* passed to postprocessing contains at least one row group's worth of samples
* above and below the row group(s) being processed. Note that the context
* rows "above" the first passed row group appear at negative row offsets in
* the passed buffer. At the top and bottom of the image, the required
* context rows are manufactured by duplicating the first or last real sample
* row; this avoids having special cases in the upsampling inner loops.
*
* The amount of context is fixed at one row group just because that's a
* convenient number for this controller to work with. The existing
* upsamplers really only need one sample row of context. An upsampler
* supporting arbitrary output rescaling might wish for more than one row
* group of context when shrinking the image; tough, we don't handle that.
* (This is justified by the assumption that downsizing will be handled mostly
* by adjusting the DCT_scaled_size values, so that the actual scale factor at
* the upsample step needn't be much less than one.)
*
* To provide the desired context, we have to retain the last two row groups
* of one iMCU row while reading in the next iMCU row. (The last row group
* can't be processed until we have another row group for its below-context,
* and so we have to save the next-to-last group too for its above-context.)
* We could do this most simply by copying data around in our buffer, but
* that'd be very slow. We can avoid copying any data by creating a rather
* strange pointer structure. Here's how it works. We allocate a workspace
* consisting of M+2 row groups (where M = min_DCT_scaled_size is the number
* of row groups per iMCU row). We create two sets of redundant pointers to
* the workspace. Labeling the physical row groups 0 to M+1, the synthesized
* pointer lists look like this:
* M+1 M-1
* master pointer --> 0 master pointer --> 0
* 1 1
* ... ...
* M-3 M-3
* M-2 M
* M-1 M+1
* M M-2
* M+1 M-1
* 0 0
* We read alternate iMCU rows using each master pointer; thus the last two
* row groups of the previous iMCU row remain un-overwritten in the workspace.
* The pointer lists are set up so that the required context rows appear to
* be adjacent to the proper places when we pass the pointer lists to the
* upsampler.
*
* The above pictures describe the normal state of the pointer lists.
* At top and bottom of the image, we diddle the pointer lists to duplicate
* the first or last sample row as necessary (this is cheaper than copying
* sample rows around).
*
* This scheme breaks down if M < 2, ie, min_DCT_scaled_size is 1. In that
* situation each iMCU row provides only one row group so the buffering logic
* must be different (eg, we must read two iMCU rows before we can emit the
* first row group). For now, we simply do not support providing context
* rows when min_DCT_scaled_size is 1. That combination seems unlikely to
* be worth providing --- if someone wants a 1/8th-size preview, they probably
* want it quick and dirty, so a context-free upsampler is sufficient.
*/
/* Private buffer controller object */
typedef struct {
struct jpeg_d_main_controller pub; /* public fields */
/* Pointer to allocated workspace (M or M+2 row groups). */
JSAMPARRAY buffer[MAX_COMPONENTS];
boolean buffer_full; /* Have we gotten an iMCU row from decoder? */
JDIMENSION rowgroup_ctr; /* counts row groups output to postprocessor */
/* Remaining fields are only used in the context case. */
/* These are the master pointers to the funny-order pointer lists. */
JSAMPIMAGE xbuffer[2]; /* pointers to weird pointer lists */
int whichptr; /* indicates which pointer set is now in use */
int context_state; /* process_data state machine status */
JDIMENSION rowgroups_avail; /* row groups available to postprocessor */
JDIMENSION iMCU_row_ctr; /* counts iMCU rows to detect image top/bot */
} my_main_controller;
typedef my_main_controller * my_main_ptr;
/* context_state values: */
#define CTX_PREPARE_FOR_IMCU 0 /* need to prepare for MCU row */
#define CTX_PROCESS_IMCU 1 /* feeding iMCU to postprocessor */
#define CTX_POSTPONED_ROW 2 /* feeding postponed row group */
/* Forward declarations */
METHODDEF(void) process_data_simple_main
JPP((j_decompress_ptr cinfo, JSAMPARRAY output_buf,
JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail));
METHODDEF(void) process_data_context_main
JPP((j_decompress_ptr cinfo, JSAMPARRAY output_buf,
JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail));
#ifdef QUANT_2PASS_SUPPORTED
METHODDEF(void) process_data_crank_post
JPP((j_decompress_ptr cinfo, JSAMPARRAY output_buf,
JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail));
#endif
LOCAL(void)
alloc_funny_pointers (j_decompress_ptr cinfo)
/* Allocate space for the funny pointer lists.
* This is done only once, not once per pass.
*/
{
my_main_ptr main = (my_main_ptr) cinfo->main;
int ci, rgroup;
int M = cinfo->min_DCT_scaled_size;
jpeg_component_info *compptr;
JSAMPARRAY xbuf;
/* Get top-level space for component array pointers.
* We alloc both arrays with one call to save a few cycles.
*/
main->xbuffer[0] = (JSAMPIMAGE)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
cinfo->num_components * 2 * SIZEOF(JSAMPARRAY));
main->xbuffer[1] = main->xbuffer[0] + cinfo->num_components;
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
rgroup = (compptr->v_samp_factor * compptr->DCT_scaled_size) /
cinfo->min_DCT_scaled_size; /* height of a row group of component */
/* Get space for pointer lists --- M+4 row groups in each list.
* We alloc both pointer lists with one call to save a few cycles.
*/
xbuf = (JSAMPARRAY)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
2 * (rgroup * (M + 4)) * SIZEOF(JSAMPROW));
xbuf += rgroup; /* want one row group at negative offsets */
main->xbuffer[0][ci] = xbuf;
xbuf += rgroup * (M + 4);
main->xbuffer[1][ci] = xbuf;
}
}
LOCAL(void)
make_funny_pointers (j_decompress_ptr cinfo)
/* Create the funny pointer lists discussed in the comments above.
* The actual workspace is already allocated (in main->buffer),
* and the space for the pointer lists is allocated too.
* This routine just fills in the curiously ordered lists.
* This will be repeated at the beginning of each pass.
*/
{
my_main_ptr main = (my_main_ptr) cinfo->main;
int ci, i, rgroup;
int M = cinfo->min_DCT_scaled_size;
jpeg_component_info *compptr;
JSAMPARRAY buf, xbuf0, xbuf1;
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
rgroup = (compptr->v_samp_factor * compptr->DCT_scaled_size) /
cinfo->min_DCT_scaled_size; /* height of a row group of component */
xbuf0 = main->xbuffer[0][ci];
xbuf1 = main->xbuffer[1][ci];
/* First copy the workspace pointers as-is */
buf = main->buffer[ci];
for (i = 0; i < rgroup * (M + 2); i++) {
xbuf0[i] = xbuf1[i] = buf[i];
}
/* In the second list, put the last four row groups in swapped order */
for (i = 0; i < rgroup * 2; i++) {
xbuf1[rgroup*(M-2) + i] = buf[rgroup*M + i];
xbuf1[rgroup*M + i] = buf[rgroup*(M-2) + i];
}
/* The wraparound pointers at top and bottom will be filled later
* (see set_wraparound_pointers, below). Initially we want the "above"
* pointers to duplicate the first actual data line. This only needs
* to happen in xbuffer[0].
*/
for (i = 0; i < rgroup; i++) {
xbuf0[i - rgroup] = xbuf0[0];
}
}
}
LOCAL(void)
set_wraparound_pointers (j_decompress_ptr cinfo)
/* Set up the "wraparound" pointers at top and bottom of the pointer lists.
* This changes the pointer list state from top-of-image to the normal state.
*/
{
my_main_ptr main = (my_main_ptr) cinfo->main;
int ci, i, rgroup;
int M = cinfo->min_DCT_scaled_size;
jpeg_component_info *compptr;
JSAMPARRAY xbuf0, xbuf1;
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
rgroup = (compptr->v_samp_factor * compptr->DCT_scaled_size) /
cinfo->min_DCT_scaled_size; /* height of a row group of component */
xbuf0 = main->xbuffer[0][ci];
xbuf1 = main->xbuffer[1][ci];
for (i = 0; i < rgroup; i++) {
xbuf0[i - rgroup] = xbuf0[rgroup*(M+1) + i];
xbuf1[i - rgroup] = xbuf1[rgroup*(M+1) + i];
xbuf0[rgroup*(M+2) + i] = xbuf0[i];
xbuf1[rgroup*(M+2) + i] = xbuf1[i];
}
}
}
LOCAL(void)
set_bottom_pointers (j_decompress_ptr cinfo)
/* Change the pointer lists to duplicate the last sample row at the bottom
* of the image. whichptr indicates which xbuffer holds the final iMCU row.
* Also sets rowgroups_avail to indicate number of nondummy row groups in row.
*/
{
my_main_ptr main = (my_main_ptr) cinfo->main;
int ci, i, rgroup, iMCUheight, rows_left;
jpeg_component_info *compptr;
JSAMPARRAY xbuf;
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
/* Count sample rows in one iMCU row and in one row group */
iMCUheight = compptr->v_samp_factor * compptr->DCT_scaled_size;
rgroup = iMCUheight / cinfo->min_DCT_scaled_size;
/* Count nondummy sample rows remaining for this component */
rows_left = (int) (compptr->downsampled_height % (JDIMENSION) iMCUheight);
if (rows_left == 0) rows_left = iMCUheight;
/* Count nondummy row groups. Should get same answer for each component,
* so we need only do it once.
*/
if (ci == 0) {
main->rowgroups_avail = (JDIMENSION) ((rows_left-1) / rgroup + 1);
}
/* Duplicate the last real sample row rgroup*2 times; this pads out the
* last partial rowgroup and ensures at least one full rowgroup of context.
*/
xbuf = main->xbuffer[main->whichptr][ci];
for (i = 0; i < rgroup * 2; i++) {
xbuf[rows_left + i] = xbuf[rows_left-1];
}
}
}
/*
* Initialize for a processing pass.
*/
METHODDEF(void)
start_pass_main (j_decompress_ptr cinfo, J_BUF_MODE pass_mode)
{
my_main_ptr main = (my_main_ptr) cinfo->main;
switch (pass_mode) {
case JBUF_PASS_THRU:
if (cinfo->upsample->need_context_rows) {
main->pub.process_data = process_data_context_main;
make_funny_pointers(cinfo); /* Create the xbuffer[] lists */
main->whichptr = 0; /* Read first iMCU row into xbuffer[0] */
main->context_state = CTX_PREPARE_FOR_IMCU;
main->iMCU_row_ctr = 0;
} else {
/* Simple case with no context needed */
main->pub.process_data = process_data_simple_main;
}
main->buffer_full = FALSE; /* Mark buffer empty */
main->rowgroup_ctr = 0;
break;
#ifdef QUANT_2PASS_SUPPORTED
case JBUF_CRANK_DEST:
/* For last pass of 2-pass quantization, just crank the postprocessor */
main->pub.process_data = process_data_crank_post;
break;
#endif
default:
ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
break;
}
}
/*
* Process some data.
* This handles the simple case where no context is required.
*/
METHODDEF(void)
process_data_simple_main (j_decompress_ptr cinfo,
JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
JDIMENSION out_rows_avail)
{
my_main_ptr main = (my_main_ptr) cinfo->main;
JDIMENSION rowgroups_avail;
/* Read input data if we haven't filled the main buffer yet */
if (! main->buffer_full) {
if (! (*cinfo->coef->decompress_data) (cinfo, main->buffer))
return; /* suspension forced, can do nothing more */
main->buffer_full = TRUE; /* OK, we have an iMCU row to work with */
}
/* There are always min_DCT_scaled_size row groups in an iMCU row. */
rowgroups_avail = (JDIMENSION) cinfo->min_DCT_scaled_size;
/* Note: at the bottom of the image, we may pass extra garbage row groups
* to the postprocessor. The postprocessor has to check for bottom
* of image anyway (at row resolution), so no point in us doing it too.
*/
/* Feed the postprocessor */
(*cinfo->post->post_process_data) (cinfo, main->buffer,
&main->rowgroup_ctr, rowgroups_avail,
output_buf, out_row_ctr, out_rows_avail);
/* Has postprocessor consumed all the data yet? If so, mark buffer empty */
if (main->rowgroup_ctr >= rowgroups_avail) {
main->buffer_full = FALSE;
main->rowgroup_ctr = 0;
}
}
/*
* Process some data.
* This handles the case where context rows must be provided.
*/
METHODDEF(void)
process_data_context_main (j_decompress_ptr cinfo,
JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
JDIMENSION out_rows_avail)
{
my_main_ptr main = (my_main_ptr) cinfo->main;
/* Read input data if we haven't filled the main buffer yet */
if (! main->buffer_full) {
if (! (*cinfo->coef->decompress_data) (cinfo,
main->xbuffer[main->whichptr]))
return; /* suspension forced, can do nothing more */
main->buffer_full = TRUE; /* OK, we have an iMCU row to work with */
main->iMCU_row_ctr++; /* count rows received */
}
/* Postprocessor typically will not swallow all the input data it is handed
* in one call (due to filling the output buffer first). Must be prepared
* to exit and restart. This switch lets us keep track of how far we got.
* Note that each case falls through to the next on successful completion.
*/
switch (main->context_state) {
case CTX_POSTPONED_ROW:
/* Call postprocessor using previously set pointers for postponed row */
(*cinfo->post->post_process_data) (cinfo, main->xbuffer[main->whichptr],
&main->rowgroup_ctr, main->rowgroups_avail,
output_buf, out_row_ctr, out_rows_avail);
if (main->rowgroup_ctr < main->rowgroups_avail)
return; /* Need to suspend */
main->context_state = CTX_PREPARE_FOR_IMCU;
if (*out_row_ctr >= out_rows_avail)
return; /* Postprocessor exactly filled output buf */
/*FALLTHROUGH*/
case CTX_PREPARE_FOR_IMCU:
/* Prepare to process first M-1 row groups of this iMCU row */
main->rowgroup_ctr = 0;
main->rowgroups_avail = (JDIMENSION) (cinfo->min_DCT_scaled_size - 1);
/* Check for bottom of image: if so, tweak pointers to "duplicate"
* the last sample row, and adjust rowgroups_avail to ignore padding rows.
*/
if (main->iMCU_row_ctr == cinfo->total_iMCU_rows)
set_bottom_pointers(cinfo);
main->context_state = CTX_PROCESS_IMCU;
/*FALLTHROUGH*/
case CTX_PROCESS_IMCU:
/* Call postprocessor using previously set pointers */
(*cinfo->post->post_process_data) (cinfo, main->xbuffer[main->whichptr],
&main->rowgroup_ctr, main->rowgroups_avail,
output_buf, out_row_ctr, out_rows_avail);
if (main->rowgroup_ctr < main->rowgroups_avail)
return; /* Need to suspend */
/* After the first iMCU, change wraparound pointers to normal state */
if (main->iMCU_row_ctr == 1)
set_wraparound_pointers(cinfo);
/* Prepare to load new iMCU row using other xbuffer list */
main->whichptr ^= 1; /* 0=>1 or 1=>0 */
main->buffer_full = FALSE;
/* Still need to process last row group of this iMCU row, */
/* which is saved at index M+1 of the other xbuffer */
main->rowgroup_ctr = (JDIMENSION) (cinfo->min_DCT_scaled_size + 1);
main->rowgroups_avail = (JDIMENSION) (cinfo->min_DCT_scaled_size + 2);
main->context_state = CTX_POSTPONED_ROW;
}
}
/*
* Process some data.
* Final pass of two-pass quantization: just call the postprocessor.
* Source data will be the postprocessor controller's internal buffer.
*/
#ifdef QUANT_2PASS_SUPPORTED
METHODDEF(void)
process_data_crank_post (j_decompress_ptr cinfo,
JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
JDIMENSION out_rows_avail)
{
(*cinfo->post->post_process_data) (cinfo, (JSAMPIMAGE) NULL,
(JDIMENSION *) NULL, (JDIMENSION) 0,
output_buf, out_row_ctr, out_rows_avail);
}
#endif /* QUANT_2PASS_SUPPORTED */
/*
* Initialize main buffer controller.
*/
GLOBAL(void)
jinit_d_main_controller (j_decompress_ptr cinfo, boolean need_full_buffer)
{
my_main_ptr main;
int ci, rgroup, ngroups;
jpeg_component_info *compptr;
main = (my_main_ptr)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
SIZEOF(my_main_controller));
cinfo->main = (struct jpeg_d_main_controller *) main;
main->pub.start_pass = start_pass_main;
if (need_full_buffer) /* shouldn't happen */
ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
/* Allocate the workspace.
* ngroups is the number of row groups we need.
*/
if (cinfo->upsample->need_context_rows) {
if (cinfo->min_DCT_scaled_size < 2) /* unsupported, see comments above */
ERREXIT(cinfo, JERR_NOTIMPL);
alloc_funny_pointers(cinfo); /* Alloc space for xbuffer[] lists */
ngroups = cinfo->min_DCT_scaled_size + 2;
} else {
ngroups = cinfo->min_DCT_scaled_size;
}
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
rgroup = (compptr->v_samp_factor * compptr->DCT_scaled_size) /
cinfo->min_DCT_scaled_size; /* height of a row group of component */
main->buffer[ci] = (*cinfo->mem->alloc_sarray)
((j_common_ptr) cinfo, JPOOL_IMAGE,
compptr->width_in_blocks * compptr->DCT_scaled_size,
(JDIMENSION) (rgroup * ngroups));
}
}
dlib/external/libjpeg/jdmarker.cpp 0 → 100644
View file @ 7cd5f664
/*
* jdmarker.c
*
* Copyright (C) 1991-1998, Thomas G. Lane.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file contains routines to decode JPEG datastream markers.
* Most of the complexity arises from our desire to support input
* suspension: if not all of the data for a marker is available,
* we must exit back to the application. On resumption, we reprocess
* the marker.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
typedef enum { /* JPEG marker codes */
M_SOF0 = 0xc0,
M_SOF1 = 0xc1,
M_SOF2 = 0xc2,
M_SOF3 = 0xc3,
M_SOF5 = 0xc5,
M_SOF6 = 0xc6,
M_SOF7 = 0xc7,
M_JPG = 0xc8,
M_SOF9 = 0xc9,
M_SOF10 = 0xca,
M_SOF11 = 0xcb,
M_SOF13 = 0xcd,
M_SOF14 = 0xce,
M_SOF15 = 0xcf,
M_DHT = 0xc4,
M_DAC = 0xcc,
M_RST0 = 0xd0,
M_RST1 = 0xd1,
M_RST2 = 0xd2,
M_RST3 = 0xd3,
M_RST4 = 0xd4,
M_RST5 = 0xd5,
M_RST6 = 0xd6,
M_RST7 = 0xd7,
M_SOI = 0xd8,
M_EOI = 0xd9,
M_SOS = 0xda,
M_DQT = 0xdb,
M_DNL = 0xdc,
M_DRI = 0xdd,
M_DHP = 0xde,
M_EXP = 0xdf,
M_APP0 = 0xe0,
M_APP1 = 0xe1,
M_APP2 = 0xe2,
M_APP3 = 0xe3,
M_APP4 = 0xe4,
M_APP5 = 0xe5,
M_APP6 = 0xe6,
M_APP7 = 0xe7,
M_APP8 = 0xe8,
M_APP9 = 0xe9,
M_APP10 = 0xea,
M_APP11 = 0xeb,
M_APP12 = 0xec,
M_APP13 = 0xed,
M_APP14 = 0xee,
M_APP15 = 0xef,
M_JPG0 = 0xf0,
M_JPG13 = 0xfd,
M_COM = 0xfe,
M_TEM = 0x01,
M_ERROR = 0x100
} JPEG_MARKER;
/* Private state */
typedef struct {
struct jpeg_marker_reader pub; /* public fields */
/* Application-overridable marker processing methods */
jpeg_marker_parser_method process_COM;
jpeg_marker_parser_method process_APPn[16];
/* Limit on marker data length to save for each marker type */
unsigned int length_limit_COM;
unsigned int length_limit_APPn[16];
/* Status of COM/APPn marker saving */
jpeg_saved_marker_ptr cur_marker; /* NULL if not processing a marker */
unsigned int bytes_read; /* data bytes read so far in marker */
/* Note: cur_marker is not linked into marker_list until it's all read. */
} my_marker_reader;
typedef my_marker_reader * my_marker_ptr;
/*
* Macros for fetching data from the data source module.
*
* At all times, cinfo->src->next_input_byte and ->bytes_in_buffer reflect
* the current restart point; we update them only when we have reached a
* suitable place to restart if a suspension occurs.
*/
/* Declare and initialize local copies of input pointer/count */
#define INPUT_VARS(cinfo) \
struct jpeg_source_mgr * datasrc = (cinfo)->src; \
const JOCTET * next_input_byte = datasrc->next_input_byte; \
size_t bytes_in_buffer = datasrc->bytes_in_buffer
/* Unload the local copies --- do this only at a restart boundary */
#define INPUT_SYNC(cinfo) \
( datasrc->next_input_byte = next_input_byte, \
datasrc->bytes_in_buffer = bytes_in_buffer )
/* Reload the local copies --- used only in MAKE_BYTE_AVAIL */
#define INPUT_RELOAD(cinfo) \
( next_input_byte = datasrc->next_input_byte, \
bytes_in_buffer = datasrc->bytes_in_buffer )
/* Internal macro for INPUT_BYTE and INPUT_2BYTES: make a byte available.
* Note we do *not* do INPUT_SYNC before calling fill_input_buffer,
* but we must reload the local copies after a successful fill.
*/
#define MAKE_BYTE_AVAIL(cinfo,action) \
if (bytes_in_buffer == 0) { \
if (! (*datasrc->fill_input_buffer) (cinfo)) \
{ action; } \
INPUT_RELOAD(cinfo); \
}
/* Read a byte into variable V.
* If must suspend, take the specified action (typically "return FALSE").
*/
#define INPUT_BYTE(cinfo,V,action) \
MAKESTMT( MAKE_BYTE_AVAIL(cinfo,action); \
bytes_in_buffer--; \
V = GETJOCTET(*next_input_byte++); )
/* As above, but read two bytes interpreted as an unsigned 16-bit integer.
* V should be declared unsigned int or perhaps INT32.
*/
#define INPUT_2BYTES(cinfo,V,action) \
MAKESTMT( MAKE_BYTE_AVAIL(cinfo,action); \
bytes_in_buffer--; \
V = ((unsigned int) GETJOCTET(*next_input_byte++)) << 8; \
MAKE_BYTE_AVAIL(cinfo,action); \
bytes_in_buffer--; \
V += GETJOCTET(*next_input_byte++); )
/*
* Routines to process JPEG markers.
*
* Entry condition: JPEG marker itself has been read and its code saved
* in cinfo->unread_marker; input restart point is just after the marker.
*
* Exit: if return TRUE, have read and processed any parameters, and have
* updated the restart point to point after the parameters.
* If return FALSE, was forced to suspend before reaching end of
* marker parameters; restart point has not been moved. Same routine
* will be called again after application supplies more input data.
*
* This approach to suspension assumes that all of a marker's parameters
* can fit into a single input bufferload. This should hold for "normal"
* markers. Some COM/APPn markers might have large parameter segments
* that might not fit. If we are simply dropping such a marker, we use
* skip_input_data to get past it, and thereby put the problem on the
* source manager's shoulders. If we are saving the marker's contents
* into memory, we use a slightly different convention: when forced to
* suspend, the marker processor updates the restart point to the end of
* what it's consumed (ie, the end of the buffer) before returning FALSE.
* On resumption, cinfo->unread_marker still contains the marker code,
* but the data source will point to the next chunk of marker data.
* The marker processor must retain internal state to deal with this.
*
* Note that we don't bother to avoid duplicate trace messages if a
* suspension occurs within marker parameters. Other side effects
* require more care.
*/
LOCAL(boolean)
get_soi (j_decompress_ptr cinfo)
/* Process an SOI marker */
{
int i;
TRACEMS(cinfo, 1, JTRC_SOI);
if (cinfo->marker->saw_SOI)
ERREXIT(cinfo, JERR_SOI_DUPLICATE);
/* Reset all parameters that are defined to be reset by SOI */
for (i = 0; i < NUM_ARITH_TBLS; i++) {
cinfo->arith_dc_L[i] = 0;
cinfo->arith_dc_U[i] = 1;
cinfo->arith_ac_K[i] = 5;
}
cinfo->restart_interval = 0;
/* Set initial assumptions for colorspace etc */
cinfo->jpeg_color_space = JCS_UNKNOWN;
cinfo->CCIR601_sampling = FALSE; /* Assume non-CCIR sampling??? */
cinfo->saw_JFIF_marker = FALSE;
cinfo->JFIF_major_version = 1; /* set default JFIF APP0 values */
cinfo->JFIF_minor_version = 1;
cinfo->density_unit = 0;
cinfo->X_density = 1;
cinfo->Y_density = 1;
cinfo->saw_Adobe_marker = FALSE;
cinfo->Adobe_transform = 0;
cinfo->marker->saw_SOI = TRUE;
return TRUE;
}
LOCAL(boolean)
get_sof (j_decompress_ptr cinfo, boolean is_prog, boolean is_arith)
/* Process a SOFn marker */
{
INT32 length;
int c, ci;
jpeg_component_info * compptr;
INPUT_VARS(cinfo);
cinfo->progressive_mode = is_prog;
cinfo->arith_code = is_arith;
INPUT_2BYTES(cinfo, length, return FALSE);
INPUT_BYTE(cinfo, cinfo->data_precision, return FALSE);
INPUT_2BYTES(cinfo, cinfo->image_height, return FALSE);
INPUT_2BYTES(cinfo, cinfo->image_width, return FALSE);
INPUT_BYTE(cinfo, cinfo->num_components, return FALSE);
length -= 8;
TRACEMS4(cinfo, 1, JTRC_SOF, cinfo->unread_marker,
(int) cinfo->image_width, (int) cinfo->image_height,
cinfo->num_components);
if (cinfo->marker->saw_SOF)
ERREXIT(cinfo, JERR_SOF_DUPLICATE);
/* We don't support files in which the image height is initially specified */
/* as 0 and is later redefined by DNL. As long as we have to check that, */
/* might as well have a general sanity check. */
if (cinfo->image_height <= 0 || cinfo->image_width <= 0
|| cinfo->num_components <= 0)
ERREXIT(cinfo, JERR_EMPTY_IMAGE);
if (length != (cinfo->num_components * 3))
ERREXIT(cinfo, JERR_BAD_LENGTH);
if (cinfo->comp_info == NULL) /* do only once, even if suspend */
cinfo->comp_info = (jpeg_component_info *) (*cinfo->mem->alloc_small)
((j_common_ptr) cinfo, JPOOL_IMAGE,
cinfo->num_components * SIZEOF(jpeg_component_info));
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
compptr->component_index = ci;
INPUT_BYTE(cinfo, compptr->component_id, return FALSE);
INPUT_BYTE(cinfo, c, return FALSE);
compptr->h_samp_factor = (c >> 4) & 15;
compptr->v_samp_factor = (c ) & 15;
INPUT_BYTE(cinfo, compptr->quant_tbl_no, return FALSE);
TRACEMS4(cinfo, 1, JTRC_SOF_COMPONENT,
compptr->component_id, compptr->h_samp_factor,
compptr->v_samp_factor, compptr->quant_tbl_no);
}
cinfo->marker->saw_SOF = TRUE;
INPUT_SYNC(cinfo);
return TRUE;
}
LOCAL(boolean)
get_sos (j_decompress_ptr cinfo)
/* Process a SOS marker */
{
INT32 length;
int i, ci, n, c, cc;
jpeg_component_info * compptr;
INPUT_VARS(cinfo);
if (! cinfo->marker->saw_SOF)
ERREXIT(cinfo, JERR_SOS_NO_SOF);
INPUT_2BYTES(cinfo, length, return FALSE);
INPUT_BYTE(cinfo, n, return FALSE); /* Number of components */
TRACEMS1(cinfo, 1, JTRC_SOS, n);
if (length != (n * 2 + 6) || n < 1 || n > MAX_COMPS_IN_SCAN)
ERREXIT(cinfo, JERR_BAD_LENGTH);
cinfo->comps_in_scan = n;
/* Collect the component-spec parameters */
for (i = 0; i < n; i++) {
INPUT_BYTE(cinfo, cc, return FALSE);
INPUT_BYTE(cinfo, c, return FALSE);
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
if (cc == compptr->component_id)
goto id_found;
}
ERREXIT1(cinfo, JERR_BAD_COMPONENT_ID, cc);
id_found:
cinfo->cur_comp_info[i] = compptr;
compptr->dc_tbl_no = (c >> 4) & 15;
compptr->ac_tbl_no = (c ) & 15;
TRACEMS3(cinfo, 1, JTRC_SOS_COMPONENT, cc,
compptr->dc_tbl_no, compptr->ac_tbl_no);
}
/* Collect the additional scan parameters Ss, Se, Ah/Al. */
INPUT_BYTE(cinfo, c, return FALSE);
cinfo->Ss = c;
INPUT_BYTE(cinfo, c, return FALSE);
cinfo->Se = c;
INPUT_BYTE(cinfo, c, return FALSE);
cinfo->Ah = (c >> 4) & 15;
cinfo->Al = (c ) & 15;
TRACEMS4(cinfo, 1, JTRC_SOS_PARAMS, cinfo->Ss, cinfo->Se,
cinfo->Ah, cinfo->Al);
/* Prepare to scan data & restart markers */
cinfo->marker->next_restart_num = 0;
/* Count another SOS marker */
cinfo->input_scan_number++;
INPUT_SYNC(cinfo);
return TRUE;
}
#ifdef D_ARITH_CODING_SUPPORTED
LOCAL(boolean)
get_dac (j_decompress_ptr cinfo)
/* Process a DAC marker */
{
INT32 length;
int index, val;
INPUT_VARS(cinfo);
INPUT_2BYTES(cinfo, length, return FALSE);
length -= 2;
while (length > 0) {
INPUT_BYTE(cinfo, index, return FALSE);
INPUT_BYTE(cinfo, val, return FALSE);
length -= 2;
TRACEMS2(cinfo, 1, JTRC_DAC, index, val);
if (index < 0 || index >= (2*NUM_ARITH_TBLS))
ERREXIT1(cinfo, JERR_DAC_INDEX, index);
if (index >= NUM_ARITH_TBLS) { /* define AC table */
cinfo->arith_ac_K[index-NUM_ARITH_TBLS] = (UINT8) val;
} else { /* define DC table */
cinfo->arith_dc_L[index] = (UINT8) (val & 0x0F);
cinfo->arith_dc_U[index] = (UINT8) (val >> 4);
if (cinfo->arith_dc_L[index] > cinfo->arith_dc_U[index])
ERREXIT1(cinfo, JERR_DAC_VALUE, val);
}
}
if (length != 0)
ERREXIT(cinfo, JERR_BAD_LENGTH);
INPUT_SYNC(cinfo);
return TRUE;
}
#else /* ! D_ARITH_CODING_SUPPORTED */
#define get_dac(cinfo) skip_variable(cinfo)
#endif /* D_ARITH_CODING_SUPPORTED */
LOCAL(boolean)
get_dht (j_decompress_ptr cinfo)
/* Process a DHT marker */
{
INT32 length;
UINT8 bits[17];
UINT8 huffval[256];
int i, index, count;
JHUFF_TBL **htblptr;
INPUT_VARS(cinfo);
INPUT_2BYTES(cinfo, length, return FALSE);
length -= 2;
while (length > 16) {
INPUT_BYTE(cinfo, index, return FALSE);
TRACEMS1(cinfo, 1, JTRC_DHT, index);
bits[0] = 0;
count = 0;
for (i = 1; i <= 16; i++) {
INPUT_BYTE(cinfo, bits[i], return FALSE);
count += bits[i];
}
length -= 1 + 16;
TRACEMS8(cinfo, 2, JTRC_HUFFBITS,
bits[1], bits[2], bits[3], bits[4],
bits[5], bits[6], bits[7], bits[8]);
TRACEMS8(cinfo, 2, JTRC_HUFFBITS,
bits[9], bits[10], bits[11], bits[12],
bits[13], bits[14], bits[15], bits[16]);
/* Here we just do minimal validation of the counts to avoid walking
* off the end of our table space. jdhuff.c will check more carefully.
*/
if (count > 256 || ((INT32) count) > length)
ERREXIT(cinfo, JERR_BAD_HUFF_TABLE);
for (i = 0; i < count; i++)
INPUT_BYTE(cinfo, huffval[i], return FALSE);
length -= count;
if (index & 0x10) { /* AC table definition */
index -= 0x10;
htblptr = &cinfo->ac_huff_tbl_ptrs[index];
} else { /* DC table definition */
htblptr = &cinfo->dc_huff_tbl_ptrs[index];
}
if (index < 0 || index >= NUM_HUFF_TBLS)
ERREXIT1(cinfo, JERR_DHT_INDEX, index);
if (*htblptr == NULL)
*htblptr = jpeg_alloc_huff_table((j_common_ptr) cinfo);
MEMCOPY((*htblptr)->bits, bits, SIZEOF((*htblptr)->bits));
MEMCOPY((*htblptr)->huffval, huffval, SIZEOF((*htblptr)->huffval));
}
if (length != 0)
ERREXIT(cinfo, JERR_BAD_LENGTH);
INPUT_SYNC(cinfo);
return TRUE;
}
LOCAL(boolean)
get_dqt (j_decompress_ptr cinfo)
/* Process a DQT marker */
{
INT32 length;
int n, i, prec;
unsigned int tmp;
JQUANT_TBL *quant_ptr;
INPUT_VARS(cinfo);
INPUT_2BYTES(cinfo, length, return FALSE);
length -= 2;
while (length > 0) {
INPUT_BYTE(cinfo, n, return FALSE);
prec = n >> 4;
n &= 0x0F;
TRACEMS2(cinfo, 1, JTRC_DQT, n, prec);
if (n >= NUM_QUANT_TBLS)
ERREXIT1(cinfo, JERR_DQT_INDEX, n);
if (cinfo->quant_tbl_ptrs[n] == NULL)
cinfo->quant_tbl_ptrs[n] = jpeg_alloc_quant_table((j_common_ptr) cinfo);
quant_ptr = cinfo->quant_tbl_ptrs[n];
for (i = 0; i < DCTSIZE2; i++) {
if (prec)
INPUT_2BYTES(cinfo, tmp, return FALSE);
else
INPUT_BYTE(cinfo, tmp, return FALSE);
/* We convert the zigzag-order table to natural array order. */
quant_ptr->quantval[jpeg_natural_order[i]] = (UINT16) tmp;
}
if (cinfo->err->trace_level >= 2) {
for (i = 0; i < DCTSIZE2; i += 8) {
TRACEMS8(cinfo, 2, JTRC_QUANTVALS,
quant_ptr->quantval[i], quant_ptr->quantval[i+1],
quant_ptr->quantval[i+2], quant_ptr->quantval[i+3],
quant_ptr->quantval[i+4], quant_ptr->quantval[i+5],
quant_ptr->quantval[i+6], quant_ptr->quantval[i+7]);
}
}
length -= DCTSIZE2+1;
if (prec) length -= DCTSIZE2;
}
if (length != 0)
ERREXIT(cinfo, JERR_BAD_LENGTH);
INPUT_SYNC(cinfo);
return TRUE;
}
LOCAL(boolean)
get_dri (j_decompress_ptr cinfo)
/* Process a DRI marker */
{
INT32 length;
unsigned int tmp;
INPUT_VARS(cinfo);
INPUT_2BYTES(cinfo, length, return FALSE);
if (length != 4)
ERREXIT(cinfo, JERR_BAD_LENGTH);
INPUT_2BYTES(cinfo, tmp, return FALSE);
TRACEMS1(cinfo, 1, JTRC_DRI, tmp);
cinfo->restart_interval = tmp;
INPUT_SYNC(cinfo);
return TRUE;
}
/*
* Routines for processing APPn and COM markers.
* These are either saved in memory or discarded, per application request.
* APP0 and APP14 are specially checked to see if they are
* JFIF and Adobe markers, respectively.
*/
#define APP0_DATA_LEN 14 /* Length of interesting data in APP0 */
#define APP14_DATA_LEN 12 /* Length of interesting data in APP14 */
#define APPN_DATA_LEN 14 /* Must be the largest of the above!! */
LOCAL(void)
examine_app0 (j_decompress_ptr cinfo, JOCTET FAR * data,
unsigned int datalen, INT32 remaining)
/* Examine first few bytes from an APP0.
* Take appropriate action if it is a JFIF marker.
* datalen is # of bytes at data[], remaining is length of rest of marker data.
*/
{
INT32 totallen = (INT32) datalen + remaining;
if (datalen >= APP0_DATA_LEN &&
GETJOCTET(data[0]) == 0x4A &&
GETJOCTET(data[1]) == 0x46 &&
GETJOCTET(data[2]) == 0x49 &&
GETJOCTET(data[3]) == 0x46 &&
GETJOCTET(data[4]) == 0) {
/* Found JFIF APP0 marker: save info */
cinfo->saw_JFIF_marker = TRUE;
cinfo->JFIF_major_version = GETJOCTET(data[5]);
cinfo->JFIF_minor_version = GETJOCTET(data[6]);
cinfo->density_unit = GETJOCTET(data[7]);
cinfo->X_density = (GETJOCTET(data[8]) << 8) + GETJOCTET(data[9]);
cinfo->Y_density = (GETJOCTET(data[10]) << 8) + GETJOCTET(data[11]);
/* Check version.
* Major version must be 1, anything else signals an incompatible change.
* (We used to treat this as an error, but now it's a nonfatal warning,
* because some bozo at Hijaak couldn't read the spec.)
* Minor version should be 0..2, but process anyway if newer.
*/
if (cinfo->JFIF_major_version != 1)
WARNMS2(cinfo, JWRN_JFIF_MAJOR,
cinfo->JFIF_major_version, cinfo->JFIF_minor_version);
/* Generate trace messages */
TRACEMS5(cinfo, 1, JTRC_JFIF,
cinfo->JFIF_major_version, cinfo->JFIF_minor_version,
cinfo->X_density, cinfo->Y_density, cinfo->density_unit);
/* Validate thumbnail dimensions and issue appropriate messages */
if (GETJOCTET(data[12]) | GETJOCTET(data[13]))
TRACEMS2(cinfo, 1, JTRC_JFIF_THUMBNAIL,
GETJOCTET(data[12]), GETJOCTET(data[13]));
totallen -= APP0_DATA_LEN;
if (totallen !=
((INT32)GETJOCTET(data[12]) * (INT32)GETJOCTET(data[13]) * (INT32) 3))
TRACEMS1(cinfo, 1, JTRC_JFIF_BADTHUMBNAILSIZE, (int) totallen);
} else if (datalen >= 6 &&
GETJOCTET(data[0]) == 0x4A &&
GETJOCTET(data[1]) == 0x46 &&
GETJOCTET(data[2]) == 0x58 &&
GETJOCTET(data[3]) == 0x58 &&
GETJOCTET(data[4]) == 0) {
/* Found JFIF "JFXX" extension APP0 marker */
/* The library doesn't actually do anything with these,
* but we try to produce a helpful trace message.
*/
switch (GETJOCTET(data[5])) {
case 0x10:
TRACEMS1(cinfo, 1, JTRC_THUMB_JPEG, (int) totallen);
break;
case 0x11:
TRACEMS1(cinfo, 1, JTRC_THUMB_PALETTE, (int) totallen);
break;
case 0x13:
TRACEMS1(cinfo, 1, JTRC_THUMB_RGB, (int) totallen);
break;
default:
TRACEMS2(cinfo, 1, JTRC_JFIF_EXTENSION,
GETJOCTET(data[5]), (int) totallen);
break;
}
} else {
/* Start of APP0 does not match "JFIF" or "JFXX", or too short */
TRACEMS1(cinfo, 1, JTRC_APP0, (int) totallen);
}
}
LOCAL(void)
examine_app14 (j_decompress_ptr cinfo, JOCTET FAR * data,
unsigned int datalen, INT32 remaining)
/* Examine first few bytes from an APP14.
* Take appropriate action if it is an Adobe marker.
* datalen is # of bytes at data[], remaining is length of rest of marker data.
*/
{
unsigned int version, flags0, flags1, transform;
if (datalen >= APP14_DATA_LEN &&
GETJOCTET(data[0]) == 0x41 &&
GETJOCTET(data[1]) == 0x64 &&
GETJOCTET(data[2]) == 0x6F &&
GETJOCTET(data[3]) == 0x62 &&
GETJOCTET(data[4]) == 0x65) {
/* Found Adobe APP14 marker */
version = (GETJOCTET(data[5]) << 8) + GETJOCTET(data[6]);
flags0 = (GETJOCTET(data[7]) << 8) + GETJOCTET(data[8]);
flags1 = (GETJOCTET(data[9]) << 8) + GETJOCTET(data[10]);
transform = GETJOCTET(data[11]);
TRACEMS4(cinfo, 1, JTRC_ADOBE, version, flags0, flags1, transform);
cinfo->saw_Adobe_marker = TRUE;
cinfo->Adobe_transform = (UINT8) transform;
} else {
/* Start of APP14 does not match "Adobe", or too short */
TRACEMS1(cinfo, 1, JTRC_APP14, (int) (datalen + remaining));
}
}
METHODDEF(boolean)
get_interesting_appn (j_decompress_ptr cinfo)
/* Process an APP0 or APP14 marker without saving it */
{
INT32 length;
JOCTET b[APPN_DATA_LEN];
unsigned int i, numtoread;
INPUT_VARS(cinfo);
INPUT_2BYTES(cinfo, length, return FALSE);
length -= 2;
/* get the interesting part of the marker data */
if (length >= APPN_DATA_LEN)
numtoread = APPN_DATA_LEN;
else if (length > 0)
numtoread = (unsigned int) length;
else
numtoread = 0;
for (i = 0; i < numtoread; i++)
INPUT_BYTE(cinfo, b[i], return FALSE);
length -= numtoread;
/* process it */
switch (cinfo->unread_marker) {
case M_APP0:
examine_app0(cinfo, (JOCTET FAR *) b, numtoread, length);
break;
case M_APP14:
examine_app14(cinfo, (JOCTET FAR *) b, numtoread, length);
break;
default:
/* can't get here unless jpeg_save_markers chooses wrong processor */
ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, cinfo->unread_marker);
break;
}
/* skip any remaining data -- could be lots */
INPUT_SYNC(cinfo);
if (length > 0)
(*cinfo->src->skip_input_data) (cinfo, (long) length);
return TRUE;
}
#ifdef SAVE_MARKERS_SUPPORTED
METHODDEF(boolean)
save_marker (j_decompress_ptr cinfo)
/* Save an APPn or COM marker into the marker list */
{
my_marker_ptr marker = (my_marker_ptr) cinfo->marker;
jpeg_saved_marker_ptr cur_marker = marker->cur_marker;
unsigned int bytes_read, data_length;
JOCTET FAR * data;
INT32 length = 0;
INPUT_VARS(cinfo);
if (cur_marker == NULL) {
/* begin reading a marker */
INPUT_2BYTES(cinfo, length, return FALSE);
length -= 2;
if (length >= 0) { /* watch out for bogus length word */
/* figure out how much we want to save */
unsigned int limit;
if (cinfo->unread_marker == (int) M_COM)
limit = marker->length_limit_COM;
else
limit = marker->length_limit_APPn[cinfo->unread_marker - (int) M_APP0];
if ((unsigned int) length < limit)
limit = (unsigned int) length;
/* allocate and initialize the marker item */
cur_marker = (jpeg_saved_marker_ptr)
(*cinfo->mem->alloc_large) ((j_common_ptr) cinfo, JPOOL_IMAGE,
SIZEOF(struct jpeg_marker_struct) + limit);
cur_marker->next = NULL;
cur_marker->marker = (UINT8) cinfo->unread_marker;
cur_marker->original_length = (unsigned int) length;
cur_marker->data_length = limit;
/* data area is just beyond the jpeg_marker_struct */
data = cur_marker->data = (JOCTET FAR *) (cur_marker + 1);
marker->cur_marker = cur_marker;
marker->bytes_read = 0;
bytes_read = 0;
data_length = limit;
} else {
/* deal with bogus length word */
bytes_read = data_length = 0;
data = NULL;
}
} else {
/* resume reading a marker */
bytes_read = marker->bytes_read;
data_length = cur_marker->data_length;
data = cur_marker->data + bytes_read;
}
while (bytes_read < data_length) {
INPUT_SYNC(cinfo); /* move the restart point to here */
marker->bytes_read = bytes_read;
/* If there's not at least one byte in buffer, suspend */
MAKE_BYTE_AVAIL(cinfo, return FALSE);
/* Copy bytes with reasonable rapidity */
while (bytes_read < data_length && bytes_in_buffer > 0) {
*data++ = *next_input_byte++;
bytes_in_buffer--;
bytes_read++;
}
}
/* Done reading what we want to read */
if (cur_marker != NULL) { /* will be NULL if bogus length word */
/* Add new marker to end of list */
if (cinfo->marker_list == NULL) {
cinfo->marker_list = cur_marker;
} else {
jpeg_saved_marker_ptr prev = cinfo->marker_list;
while (prev->next != NULL)
prev = prev->next;
prev->next = cur_marker;
}
/* Reset pointer & calc remaining data length */
data = cur_marker->data;
length = cur_marker->original_length - data_length;
}
/* Reset to initial state for next marker */
marker->cur_marker = NULL;
/* Process the marker if interesting; else just make a generic trace msg */
switch (cinfo->unread_marker) {
case M_APP0:
examine_app0(cinfo, data, data_length, length);
break;
case M_APP14:
examine_app14(cinfo, data, data_length, length);
break;
default:
TRACEMS2(cinfo, 1, JTRC_MISC_MARKER, cinfo->unread_marker,
(int) (data_length + length));
break;
}
/* skip any remaining data -- could be lots */
INPUT_SYNC(cinfo); /* do before skip_input_data */
if (length > 0)
(*cinfo->src->skip_input_data) (cinfo, (long) length);
return TRUE;
}
#endif /* SAVE_MARKERS_SUPPORTED */
METHODDEF(boolean)
skip_variable (j_decompress_ptr cinfo)
/* Skip over an unknown or uninteresting variable-length marker */
{
INT32 length;
INPUT_VARS(cinfo);
INPUT_2BYTES(cinfo, length, return FALSE);
length -= 2;
TRACEMS2(cinfo, 1, JTRC_MISC_MARKER, cinfo->unread_marker, (int) length);
INPUT_SYNC(cinfo); /* do before skip_input_data */
if (length > 0)
(*cinfo->src->skip_input_data) (cinfo, (long) length);
return TRUE;
}
/*
* Find the next JPEG marker, save it in cinfo->unread_marker.
* Returns FALSE if had to suspend before reaching a marker;
* in that case cinfo->unread_marker is unchanged.
*
* Note that the result might not be a valid marker code,
* but it will never be 0 or FF.
*/
LOCAL(boolean)
next_marker (j_decompress_ptr cinfo)
{
int c;
INPUT_VARS(cinfo);
for (;;) {
INPUT_BYTE(cinfo, c, return FALSE);
/* Skip any non-FF bytes.
* This may look a bit inefficient, but it will not occur in a valid file.
* We sync after each discarded byte so that a suspending data source
* can discard the byte from its buffer.
*/
while (c != 0xFF) {
cinfo->marker->discarded_bytes++;
INPUT_SYNC(cinfo);
INPUT_BYTE(cinfo, c, return FALSE);
}
/* This loop swallows any duplicate FF bytes. Extra FFs are legal as
* pad bytes, so don't count them in discarded_bytes. We assume there
* will not be so many consecutive FF bytes as to overflow a suspending
* data source's input buffer.
*/
do {
INPUT_BYTE(cinfo, c, return FALSE);
} while (c == 0xFF);
if (c != 0)
break; /* found a valid marker, exit loop */
/* Reach here if we found a stuffed-zero data sequence (FF/00).
* Discard it and loop back to try again.
*/
cinfo->marker->discarded_bytes += 2;
INPUT_SYNC(cinfo);
}
if (cinfo->marker->discarded_bytes != 0) {
WARNMS2(cinfo, JWRN_EXTRANEOUS_DATA, cinfo->marker->discarded_bytes, c);
cinfo->marker->discarded_bytes = 0;
}
cinfo->unread_marker = c;
INPUT_SYNC(cinfo);
return TRUE;
}
LOCAL(boolean)
first_marker (j_decompress_ptr cinfo)
/* Like next_marker, but used to obtain the initial SOI marker. */
/* For this marker, we do not allow preceding garbage or fill; otherwise,
* we might well scan an entire input file before realizing it ain't JPEG.
* If an application wants to process non-JFIF files, it must seek to the
* SOI before calling the JPEG library.
*/
{
int c, c2;
INPUT_VARS(cinfo);
INPUT_BYTE(cinfo, c, return FALSE);
INPUT_BYTE(cinfo, c2, return FALSE);
if (c != 0xFF || c2 != (int) M_SOI)
ERREXIT2(cinfo, JERR_NO_SOI, c, c2);
cinfo->unread_marker = c2;
INPUT_SYNC(cinfo);
return TRUE;
}
/*
* Read markers until SOS or EOI.
*
* Returns same codes as are defined for jpeg_consume_input:
* JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI.
*/
METHODDEF(int)
read_markers (j_decompress_ptr cinfo)
{
/* Outer loop repeats once for each marker. */
for (;;) {
/* Collect the marker proper, unless we already did. */
/* NB: first_marker() enforces the requirement that SOI appear first. */
if (cinfo->unread_marker == 0) {
if (! cinfo->marker->saw_SOI) {
if (! first_marker(cinfo))
return JPEG_SUSPENDED;
} else {
if (! next_marker(cinfo))
return JPEG_SUSPENDED;
}
}
/* At this point cinfo->unread_marker contains the marker code and the
* input point is just past the marker proper, but before any parameters.
* A suspension will cause us to return with this state still true.
*/
switch (cinfo->unread_marker) {
case M_SOI:
if (! get_soi(cinfo))
return JPEG_SUSPENDED;
break;
case M_SOF0: /* Baseline */
case M_SOF1: /* Extended sequential, Huffman */
if (! get_sof(cinfo, FALSE, FALSE))
return JPEG_SUSPENDED;
break;
case M_SOF2: /* Progressive, Huffman */
if (! get_sof(cinfo, TRUE, FALSE))
return JPEG_SUSPENDED;
break;
case M_SOF9: /* Extended sequential, arithmetic */
if (! get_sof(cinfo, FALSE, TRUE))
return JPEG_SUSPENDED;
break;
case M_SOF10: /* Progressive, arithmetic */
if (! get_sof(cinfo, TRUE, TRUE))
return JPEG_SUSPENDED;
break;
/* Currently unsupported SOFn types */
case M_SOF3: /* Lossless, Huffman */
case M_SOF5: /* Differential sequential, Huffman */
case M_SOF6: /* Differential progressive, Huffman */
case M_SOF7: /* Differential lossless, Huffman */
case M_JPG: /* Reserved for JPEG extensions */
case M_SOF11: /* Lossless, arithmetic */
case M_SOF13: /* Differential sequential, arithmetic */
case M_SOF14: /* Differential progressive, arithmetic */
case M_SOF15: /* Differential lossless, arithmetic */
ERREXIT1(cinfo, JERR_SOF_UNSUPPORTED, cinfo->unread_marker);
break;
case M_SOS:
if (! get_sos(cinfo))
return JPEG_SUSPENDED;
cinfo->unread_marker = 0; /* processed the marker */
return JPEG_REACHED_SOS;
case M_EOI:
TRACEMS(cinfo, 1, JTRC_EOI);
cinfo->unread_marker = 0; /* processed the marker */
return JPEG_REACHED_EOI;
case M_DAC:
if (! get_dac(cinfo))
return JPEG_SUSPENDED;
break;
case M_DHT:
if (! get_dht(cinfo))
return JPEG_SUSPENDED;
break;
case M_DQT:
if (! get_dqt(cinfo))
return JPEG_SUSPENDED;
break;
case M_DRI:
if (! get_dri(cinfo))
return JPEG_SUSPENDED;
break;
case M_APP0:
case M_APP1:
case M_APP2:
case M_APP3:
case M_APP4:
case M_APP5:
case M_APP6:
case M_APP7:
case M_APP8:
case M_APP9:
case M_APP10:
case M_APP11:
case M_APP12:
case M_APP13:
case M_APP14:
case M_APP15:
if (! (*((my_marker_ptr) cinfo->marker)->process_APPn[
cinfo->unread_marker - (int) M_APP0]) (cinfo))
return JPEG_SUSPENDED;
break;
case M_COM:
if (! (*((my_marker_ptr) cinfo->marker)->process_COM) (cinfo))
return JPEG_SUSPENDED;
break;
case M_RST0: /* these are all parameterless */
case M_RST1:
case M_RST2:
case M_RST3:
case M_RST4:
case M_RST5:
case M_RST6:
case M_RST7:
case M_TEM:
TRACEMS1(cinfo, 1, JTRC_PARMLESS_MARKER, cinfo->unread_marker);
break;
case M_DNL: /* Ignore DNL ... perhaps the wrong thing */
if (! skip_variable(cinfo))
return JPEG_SUSPENDED;
break;
default: /* must be DHP, EXP, JPGn, or RESn */
/* For now, we treat the reserved markers as fatal errors since they are
* likely to be used to signal incompatible JPEG Part 3 extensions.
* Once the JPEG 3 version-number marker is well defined, this code
* ought to change!
*/
ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, cinfo->unread_marker);
break;
}
/* Successfully processed marker, so reset state variable */
cinfo->unread_marker = 0;
} /* end loop */
}
/*
* Read a restart marker, which is expected to appear next in the datastream;
* if the marker is not there, take appropriate recovery action.
* Returns FALSE if suspension is required.
*
* This is called by the entropy decoder after it has read an appropriate
* number of MCUs. cinfo->unread_marker may be nonzero if the entropy decoder
* has already read a marker from the data source. Under normal conditions
* cinfo->unread_marker will be reset to 0 before returning; if not reset,
* it holds a marker which the decoder will be unable to read past.
*/
METHODDEF(boolean)
read_restart_marker (j_decompress_ptr cinfo)
{
/* Obtain a marker unless we already did. */
/* Note that next_marker will complain if it skips any data. */
if (cinfo->unread_marker == 0) {
if (! next_marker(cinfo))
return FALSE;
}
if (cinfo->unread_marker ==
((int) M_RST0 + cinfo->marker->next_restart_num)) {
/* Normal case --- swallow the marker and let entropy decoder continue */
TRACEMS1(cinfo, 3, JTRC_RST, cinfo->marker->next_restart_num);
cinfo->unread_marker = 0;
} else {
/* Uh-oh, the restart markers have been messed up. */
/* Let the data source manager determine how to resync. */
if (! (*cinfo->src->resync_to_restart) (cinfo,
cinfo->marker->next_restart_num))
return FALSE;
}
/* Update next-restart state */
cinfo->marker->next_restart_num = (cinfo->marker->next_restart_num + 1) & 7;
return TRUE;
}
/*
* This is the default resync_to_restart method for data source managers
* to use if they don't have any better approach. Some data source managers
* may be able to back up, or may have additional knowledge about the data
* which permits a more intelligent recovery strategy; such managers would
* presumably supply their own resync method.
*
* read_restart_marker calls resync_to_restart if it finds a marker other than
* the restart marker it was expecting. (This code is *not* used unless
* a nonzero restart interval has been declared.) cinfo->unread_marker is
* the marker code actually found (might be anything, except 0 or FF).
* The desired restart marker number (0..7) is passed as a parameter.
* This routine is supposed to apply whatever error recovery strategy seems
* appropriate in order to position the input stream to the next data segment.
* Note that cinfo->unread_marker is treated as a marker appearing before
* the current data-source input point; usually it should be reset to zero
* before returning.
* Returns FALSE if suspension is required.
*
* This implementation is substantially constrained by wanting to treat the
* input as a data stream; this means we can't back up. Therefore, we have
* only the following actions to work with:
* 1. Simply discard the marker and let the entropy decoder resume at next
* byte of file.
* 2. Read forward until we find another marker, discarding intervening
* data. (In theory we could look ahead within the current bufferload,
* without having to discard data if we don't find the desired marker.
* This idea is not implemented here, in part because it makes behavior
* dependent on buffer size and chance buffer-boundary positions.)
* 3. Leave the marker unread (by failing to zero cinfo->unread_marker).
* This will cause the entropy decoder to process an empty data segment,
* inserting dummy zeroes, and then we will reprocess the marker.
*
* #2 is appropriate if we think the desired marker lies ahead, while #3 is
* appropriate if the found marker is a future restart marker (indicating
* that we have missed the desired restart marker, probably because it got
* corrupted).
* We apply #2 or #3 if the found marker is a restart marker no more than
* two counts behind or ahead of the expected one. We also apply #2 if the
* found marker is not a legal JPEG marker code (it's certainly bogus data).
* If the found marker is a restart marker more than 2 counts away, we do #1
* (too much risk that the marker is erroneous; with luck we will be able to
* resync at some future point).
* For any valid non-restart JPEG marker, we apply #3. This keeps us from
* overrunning the end of a scan. An implementation limited to single-scan
* files might find it better to apply #2 for markers other than EOI, since
* any other marker would have to be bogus data in that case.
*/
GLOBAL(boolean)
jpeg_resync_to_restart (j_decompress_ptr cinfo, int desired)
{
int marker = cinfo->unread_marker;
int action = 1;
/* Always put up a warning. */
WARNMS2(cinfo, JWRN_MUST_RESYNC, marker, desired);
/* Outer loop handles repeated decision after scanning forward. */
for (;;) {
if (marker < (int) M_SOF0)
action = 2; /* invalid marker */
else if (marker < (int) M_RST0 || marker > (int) M_RST7)
action = 3; /* valid non-restart marker */
else {
if (marker == ((int) M_RST0 + ((desired+1) & 7)) ||
marker == ((int) M_RST0 + ((desired+2) & 7)))
action = 3; /* one of the next two expected restarts */
else if (marker == ((int) M_RST0 + ((desired-1) & 7)) ||
marker == ((int) M_RST0 + ((desired-2) & 7)))
action = 2; /* a prior restart, so advance */
else
action = 1; /* desired restart or too far away */
}
TRACEMS2(cinfo, 4, JTRC_RECOVERY_ACTION, marker, action);
switch (action) {
case 1:
/* Discard marker and let entropy decoder resume processing. */
cinfo->unread_marker = 0;
return TRUE;
case 2:
/* Scan to the next marker, and repeat the decision loop. */
if (! next_marker(cinfo))
return FALSE;
marker = cinfo->unread_marker;
break;
case 3:
/* Return without advancing past this marker. */
/* Entropy decoder will be forced to process an empty segment. */
return TRUE;
}
} /* end loop */
}
/*
* Reset marker processing state to begin a fresh datastream.
*/
METHODDEF(void)
reset_marker_reader (j_decompress_ptr cinfo)
{
my_marker_ptr marker = (my_marker_ptr) cinfo->marker;
cinfo->comp_info = NULL; /* until allocated by get_sof */
cinfo->input_scan_number = 0; /* no SOS seen yet */
cinfo->unread_marker = 0; /* no pending marker */
marker->pub.saw_SOI = FALSE; /* set internal state too */
marker->pub.saw_SOF = FALSE;
marker->pub.discarded_bytes = 0;
marker->cur_marker = NULL;
}
/*
* Initialize the marker reader module.
* This is called only once, when the decompression object is created.
*/
GLOBAL(void)
jinit_marker_reader (j_decompress_ptr cinfo)
{
my_marker_ptr marker;
int i;
/* Create subobject in permanent pool */
marker = (my_marker_ptr)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
SIZEOF(my_marker_reader));
cinfo->marker = (struct jpeg_marker_reader *) marker;
/* Initialize public method pointers */
marker->pub.reset_marker_reader = reset_marker_reader;
marker->pub.read_markers = read_markers;
marker->pub.read_restart_marker = read_restart_marker;
/* Initialize COM/APPn processing.
* By default, we examine and then discard APP0 and APP14,
* but simply discard COM and all other APPn.
*/
marker->process_COM = skip_variable;
marker->length_limit_COM = 0;
for (i = 0; i < 16; i++) {
marker->process_APPn[i] = skip_variable;
marker->length_limit_APPn[i] = 0;
}
marker->process_APPn[0] = get_interesting_appn;
marker->process_APPn[14] = get_interesting_appn;
/* Reset marker processing state */
reset_marker_reader(cinfo);
}
/*
* Control saving of COM and APPn markers into marker_list.
*/
#ifdef SAVE_MARKERS_SUPPORTED
GLOBAL(void)
jpeg_save_markers (j_decompress_ptr cinfo, int marker_code,
unsigned int length_limit)
{
my_marker_ptr marker = (my_marker_ptr) cinfo->marker;
long maxlength;
jpeg_marker_parser_method processor;
/* Length limit mustn't be larger than what we can allocate
* (should only be a concern in a 16-bit environment).
*/
maxlength = cinfo->mem->max_alloc_chunk - SIZEOF(struct jpeg_marker_struct);
if (((long) length_limit) > maxlength)
length_limit = (unsigned int) maxlength;
/* Choose processor routine to use.
* APP0/APP14 have special requirements.
*/
if (length_limit) {
processor = save_marker;
/* If saving APP0/APP14, save at least enough for our internal use. */
if (marker_code == (int) M_APP0 && length_limit < APP0_DATA_LEN)
length_limit = APP0_DATA_LEN;
else if (marker_code == (int) M_APP14 && length_limit < APP14_DATA_LEN)
length_limit = APP14_DATA_LEN;
} else {
processor = skip_variable;
/* If discarding APP0/APP14, use our regular on-the-fly processor. */
if (marker_code == (int) M_APP0 || marker_code == (int) M_APP14)
processor = get_interesting_appn;
}
if (marker_code == (int) M_COM) {
marker->process_COM = processor;
marker->length_limit_COM = length_limit;
} else if (marker_code >= (int) M_APP0 && marker_code <= (int) M_APP15) {
marker->process_APPn[marker_code - (int) M_APP0] = processor;
marker->length_limit_APPn[marker_code - (int) M_APP0] = length_limit;
} else
ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, marker_code);
}
#endif /* SAVE_MARKERS_SUPPORTED */
/*
* Install a special processing method for COM or APPn markers.
*/
GLOBAL(void)
jpeg_set_marker_processor (j_decompress_ptr cinfo, int marker_code,
jpeg_marker_parser_method routine)
{
my_marker_ptr marker = (my_marker_ptr) cinfo->marker;
if (marker_code == (int) M_COM)
marker->process_COM = routine;
else if (marker_code >= (int) M_APP0 && marker_code <= (int) M_APP15)
marker->process_APPn[marker_code - (int) M_APP0] = routine;
else
ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, marker_code);
}
dlib/external/libjpeg/jdmaster.cpp 0 → 100644
View file @ 7cd5f664
/*
* jdmaster.c
*
* Copyright (C) 1991-1997, Thomas G. Lane.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file contains master control logic for the JPEG decompressor.
* These routines are concerned with selecting the modules to be executed
* and with determining the number of passes and the work to be done in each
* pass.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
/* Private state */
typedef struct {
struct jpeg_decomp_master pub; /* public fields */
int pass_number; /* # of passes completed */
boolean using_merged_upsample; /* TRUE if using merged upsample/cconvert */
/* Saved references to initialized quantizer modules,
* in case we need to switch modes.
*/
struct jpeg_color_quantizer * quantizer_1pass;
struct jpeg_color_quantizer * quantizer_2pass;
} my_decomp_master;
typedef my_decomp_master * my_master_ptr;
/*
* Determine whether merged upsample/color conversion should be used.
* CRUCIAL: this must match the actual capabilities of jdmerge.c!
*/
LOCAL(boolean)
use_merged_upsample (j_decompress_ptr cinfo)
{
#ifdef UPSAMPLE_MERGING_SUPPORTED
/* Merging is the equivalent of plain box-filter upsampling */
if (cinfo->do_fancy_upsampling || cinfo->CCIR601_sampling)
return FALSE;
/* jdmerge.c only supports YCC=>RGB color conversion */
if (cinfo->jpeg_color_space != JCS_YCbCr || cinfo->num_components != 3 ||
cinfo->out_color_space != JCS_RGB ||
cinfo->out_color_components != RGB_PIXELSIZE)
return FALSE;
/* and it only handles 2h1v or 2h2v sampling ratios */
if (cinfo->comp_info[0].h_samp_factor != 2 ||
cinfo->comp_info[1].h_samp_factor != 1 ||
cinfo->comp_info[2].h_samp_factor != 1 ||
cinfo->comp_info[0].v_samp_factor > 2 ||
cinfo->comp_info[1].v_samp_factor != 1 ||
cinfo->comp_info[2].v_samp_factor != 1)
return FALSE;
/* furthermore, it doesn't work if we've scaled the IDCTs differently */
if (cinfo->comp_info[0].DCT_scaled_size != cinfo->min_DCT_scaled_size ||
cinfo->comp_info[1].DCT_scaled_size != cinfo->min_DCT_scaled_size ||
cinfo->comp_info[2].DCT_scaled_size != cinfo->min_DCT_scaled_size)
return FALSE;
/* ??? also need to test for upsample-time rescaling, when & if supported */
return TRUE; /* by golly, it'll work... */
#else
return FALSE;
#endif
}
/*
* Compute output image dimensions and related values.
* NOTE: this is exported for possible use by application.
* Hence it mustn't do anything that can't be done twice.
* Also note that it may be called before the master module is initialized!
*/
GLOBAL(void)
jpeg_calc_output_dimensions (j_decompress_ptr cinfo)
/* Do computations that are needed before master selection phase */
{
#ifdef IDCT_SCALING_SUPPORTED
int ci;
jpeg_component_info *compptr;
#endif
/* Prevent application from calling me at wrong times */
if (cinfo->global_state != DSTATE_READY)
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
#ifdef IDCT_SCALING_SUPPORTED
/* Compute actual output image dimensions and DCT scaling choices. */
if (cinfo->scale_num * 8 <= cinfo->scale_denom) {
/* Provide 1/8 scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width, 8L);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height, 8L);
cinfo->min_DCT_scaled_size = 1;
} else if (cinfo->scale_num * 4 <= cinfo->scale_denom) {
/* Provide 1/4 scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width, 4L);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height, 4L);
cinfo->min_DCT_scaled_size = 2;
} else if (cinfo->scale_num * 2 <= cinfo->scale_denom) {
/* Provide 1/2 scaling */
cinfo->output_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width, 2L);
cinfo->output_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height, 2L);
cinfo->min_DCT_scaled_size = 4;
} else {
/* Provide 1/1 scaling */
cinfo->output_width = cinfo->image_width;
cinfo->output_height = cinfo->image_height;
cinfo->min_DCT_scaled_size = DCTSIZE;
}
/* In selecting the actual DCT scaling for each component, we try to
* scale up the chroma components via IDCT scaling rather than upsampling.
* This saves time if the upsampler gets to use 1:1 scaling.
* Note this code assumes that the supported DCT scalings are powers of 2.
*/
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
int ssize = cinfo->min_DCT_scaled_size;
while (ssize < DCTSIZE &&
(compptr->h_samp_factor * ssize * 2 <=
cinfo->max_h_samp_factor * cinfo->min_DCT_scaled_size) &&
(compptr->v_samp_factor * ssize * 2 <=
cinfo->max_v_samp_factor * cinfo->min_DCT_scaled_size)) {
ssize = ssize * 2;
}
compptr->DCT_scaled_size = ssize;
}
/* Recompute downsampled dimensions of components;
* application needs to know these if using raw downsampled data.
*/
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
/* Size in samples, after IDCT scaling */
compptr->downsampled_width = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width *
(long) (compptr->h_samp_factor * compptr->DCT_scaled_size),
(long) (cinfo->max_h_samp_factor * DCTSIZE));
compptr->downsampled_height = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height *
(long) (compptr->v_samp_factor * compptr->DCT_scaled_size),
(long) (cinfo->max_v_samp_factor * DCTSIZE));
}
#else /* !IDCT_SCALING_SUPPORTED */
/* Hardwire it to "no scaling" */
cinfo->output_width = cinfo->image_width;
cinfo->output_height = cinfo->image_height;
/* jdinput.c has already initialized DCT_scaled_size to DCTSIZE,
* and has computed unscaled downsampled_width and downsampled_height.
*/
#endif /* IDCT_SCALING_SUPPORTED */
/* Report number of components in selected colorspace. */
/* Probably this should be in the color conversion module... */
switch (cinfo->out_color_space) {
case JCS_GRAYSCALE:
cinfo->out_color_components = 1;
break;
case JCS_RGB:
#if RGB_PIXELSIZE != 3
cinfo->out_color_components = RGB_PIXELSIZE;
break;
#endif /* else share code with YCbCr */
case JCS_YCbCr:
cinfo->out_color_components = 3;
break;
case JCS_CMYK:
case JCS_YCCK:
cinfo->out_color_components = 4;
break;
default: /* else must be same colorspace as in file */
cinfo->out_color_components = cinfo->num_components;
break;
}
cinfo->output_components = (cinfo->quantize_colors ? 1 :
cinfo->out_color_components);
/* See if upsampler will want to emit more than one row at a time */
if (use_merged_upsample(cinfo))
cinfo->rec_outbuf_height = cinfo->max_v_samp_factor;
else
cinfo->rec_outbuf_height = 1;
}
/*
* Several decompression processes need to range-limit values to the range
* 0..MAXJSAMPLE; the input value may fall somewhat outside this range
* due to noise introduced by quantization, roundoff error, etc. These
* processes are inner loops and need to be as fast as possible. On most
* machines, particularly CPUs with pipelines or instruction prefetch,
* a (subscript-check-less) C table lookup
* x = sample_range_limit[x];
* is faster than explicit tests
* if (x < 0) x = 0;
* else if (x > MAXJSAMPLE) x = MAXJSAMPLE;
* These processes all use a common table prepared by the routine below.
*
* For most steps we can mathematically guarantee that the initial value
* of x is within MAXJSAMPLE+1 of the legal range, so a table running from
* -(MAXJSAMPLE+1) to 2*MAXJSAMPLE+1 is sufficient. But for the initial
* limiting step (just after the IDCT), a wildly out-of-range value is
* possible if the input data is corrupt. To avoid any chance of indexing
* off the end of memory and getting a bad-pointer trap, we perform the
* post-IDCT limiting thus:
* x = range_limit[x & MASK];
* where MASK is 2 bits wider than legal sample data, ie 10 bits for 8-bit
* samples. Under normal circumstances this is more than enough range and
* a correct output will be generated; with bogus input data the mask will
* cause wraparound, and we will safely generate a bogus-but-in-range output.
* For the post-IDCT step, we want to convert the data from signed to unsigned
* representation by adding CENTERJSAMPLE at the same time that we limit it.
* So the post-IDCT limiting table ends up looking like this:
* CENTERJSAMPLE,CENTERJSAMPLE+1,...,MAXJSAMPLE,
* MAXJSAMPLE (repeat 2*(MAXJSAMPLE+1)-CENTERJSAMPLE times),
* 0 (repeat 2*(MAXJSAMPLE+1)-CENTERJSAMPLE times),
* 0,1,...,CENTERJSAMPLE-1
* Negative inputs select values from the upper half of the table after
* masking.
*
* We can save some space by overlapping the start of the post-IDCT table
* with the simpler range limiting table. The post-IDCT table begins at
* sample_range_limit + CENTERJSAMPLE.
*
* Note that the table is allocated in near data space on PCs; it's small
* enough and used often enough to justify this.
*/
LOCAL(void)
prepare_range_limit_table (j_decompress_ptr cinfo)
/* Allocate and fill in the sample_range_limit table */
{
JSAMPLE * table;
int i;
table = (JSAMPLE *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
(5 * (MAXJSAMPLE+1) + CENTERJSAMPLE) * SIZEOF(JSAMPLE));
table += (MAXJSAMPLE+1); /* allow negative subscripts of simple table */
cinfo->sample_range_limit = table;
/* First segment of "simple" table: limit[x] = 0 for x < 0 */
MEMZERO(table - (MAXJSAMPLE+1), (MAXJSAMPLE+1) * SIZEOF(JSAMPLE));
/* Main part of "simple" table: limit[x] = x */
for (i = 0; i <= MAXJSAMPLE; i++)
table[i] = (JSAMPLE) i;
table += CENTERJSAMPLE; /* Point to where post-IDCT table starts */
/* End of simple table, rest of first half of post-IDCT table */
for (i = CENTERJSAMPLE; i < 2*(MAXJSAMPLE+1); i++)
table[i] = MAXJSAMPLE;
/* Second half of post-IDCT table */
MEMZERO(table + (2 * (MAXJSAMPLE+1)),
(2 * (MAXJSAMPLE+1) - CENTERJSAMPLE) * SIZEOF(JSAMPLE));
MEMCOPY(table + (4 * (MAXJSAMPLE+1) - CENTERJSAMPLE),
cinfo->sample_range_limit, CENTERJSAMPLE * SIZEOF(JSAMPLE));
}
/*
* Master selection of decompression modules.
* This is done once at jpeg_start_decompress time. We determine
* which modules will be used and give them appropriate initialization calls.
* We also initialize the decompressor input side to begin consuming data.
*
* Since jpeg_read_header has finished, we know what is in the SOF
* and (first) SOS markers. We also have all the application parameter
* settings.
*/
LOCAL(void)
master_selection (j_decompress_ptr cinfo)
{
my_master_ptr master = (my_master_ptr) cinfo->master;
boolean use_c_buffer;
long samplesperrow;
JDIMENSION jd_samplesperrow;
/* Initialize dimensions and other stuff */
jpeg_calc_output_dimensions(cinfo);
prepare_range_limit_table(cinfo);
/* Width of an output scanline must be representable as JDIMENSION. */
samplesperrow = (long) cinfo->output_width * (long) cinfo->out_color_components;
jd_samplesperrow = (JDIMENSION) samplesperrow;
if ((long) jd_samplesperrow != samplesperrow)
ERREXIT(cinfo, JERR_WIDTH_OVERFLOW);
/* Initialize my private state */
master->pass_number = 0;
master->using_merged_upsample = use_merged_upsample(cinfo);
/* Color quantizer selection */
master->quantizer_1pass = NULL;
master->quantizer_2pass = NULL;
/* No mode changes if not using buffered-image mode. */
if (! cinfo->quantize_colors || ! cinfo->buffered_image) {
cinfo->enable_1pass_quant = FALSE;
cinfo->enable_external_quant = FALSE;
cinfo->enable_2pass_quant = FALSE;
}
if (cinfo->quantize_colors) {
if (cinfo->raw_data_out)
ERREXIT(cinfo, JERR_NOTIMPL);
/* 2-pass quantizer only works in 3-component color space. */
if (cinfo->out_color_components != 3) {
cinfo->enable_1pass_quant = TRUE;
cinfo->enable_external_quant = FALSE;
cinfo->enable_2pass_quant = FALSE;
cinfo->colormap = NULL;
} else if (cinfo->colormap != NULL) {
cinfo->enable_external_quant = TRUE;
} else if (cinfo->two_pass_quantize) {
cinfo->enable_2pass_quant = TRUE;
} else {
cinfo->enable_1pass_quant = TRUE;
}
if (cinfo->enable_1pass_quant) {
#ifdef QUANT_1PASS_SUPPORTED
jinit_1pass_quantizer(cinfo);
master->quantizer_1pass = cinfo->cquantize;
#else
ERREXIT(cinfo, JERR_NOT_COMPILED);
#endif
}
/* We use the 2-pass code to map to external colormaps. */
if (cinfo->enable_2pass_quant || cinfo->enable_external_quant) {
#ifdef QUANT_2PASS_SUPPORTED
jinit_2pass_quantizer(cinfo);
master->quantizer_2pass = cinfo->cquantize;
#else
ERREXIT(cinfo, JERR_NOT_COMPILED);
#endif
}
/* If both quantizers are initialized, the 2-pass one is left active;
* this is necessary for starting with quantization to an external map.
*/
}
/* Post-processing: in particular, color conversion first */
if (! cinfo->raw_data_out) {
if (master->using_merged_upsample) {
#ifdef UPSAMPLE_MERGING_SUPPORTED
jinit_merged_upsampler(cinfo); /* does color conversion too */
#else
ERREXIT(cinfo, JERR_NOT_COMPILED);
#endif
} else {
jinit_color_deconverter(cinfo);
jinit_upsampler(cinfo);
}
jinit_d_post_controller(cinfo, cinfo->enable_2pass_quant);
}
/* Inverse DCT */
jinit_inverse_dct(cinfo);
/* Entropy decoding: either Huffman or arithmetic coding. */
if (cinfo->arith_code) {
ERREXIT(cinfo, JERR_ARITH_NOTIMPL);
} else {
if (cinfo->progressive_mode) {
#ifdef D_PROGRESSIVE_SUPPORTED
jinit_phuff_decoder(cinfo);
#else
ERREXIT(cinfo, JERR_NOT_COMPILED);
#endif
} else
jinit_huff_decoder(cinfo);
}
/* Initialize principal buffer controllers. */
use_c_buffer = cinfo->inputctl->has_multiple_scans || cinfo->buffered_image;
jinit_d_coef_controller(cinfo, use_c_buffer);
if (! cinfo->raw_data_out)
jinit_d_main_controller(cinfo, FALSE /* never need full buffer here */);
/* We can now tell the memory manager to allocate virtual arrays. */
(*cinfo->mem->realize_virt_arrays) ((j_common_ptr) cinfo);
/* Initialize input side of decompressor to consume first scan. */
(*cinfo->inputctl->start_input_pass) (cinfo);
#ifdef D_MULTISCAN_FILES_SUPPORTED
/* If jpeg_start_decompress will read the whole file, initialize
* progress monitoring appropriately. The input step is counted
* as one pass.
*/
if (cinfo->progress != NULL && ! cinfo->buffered_image &&
cinfo->inputctl->has_multiple_scans) {
int nscans;
/* Estimate number of scans to set pass_limit. */
if (cinfo->progressive_mode) {
/* Arbitrarily estimate 2 interleaved DC scans + 3 AC scans/component. */
nscans = 2 + 3 * cinfo->num_components;
} else {
/* For a nonprogressive multiscan file, estimate 1 scan per component. */
nscans = cinfo->num_components;
}
cinfo->progress->pass_counter = 0L;
cinfo->progress->pass_limit = (long) cinfo->total_iMCU_rows * nscans;
cinfo->progress->completed_passes = 0;
cinfo->progress->total_passes = (cinfo->enable_2pass_quant ? 3 : 2);
/* Count the input pass as done */
master->pass_number++;
}
#endif /* D_MULTISCAN_FILES_SUPPORTED */
}
/*
* Per-pass setup.
* This is called at the beginning of each output pass. We determine which
* modules will be active during this pass and give them appropriate
* start_pass calls. We also set is_dummy_pass to indicate whether this
* is a "real" output pass or a dummy pass for color quantization.
* (In the latter case, jdapistd.c will crank the pass to completion.)
*/
METHODDEF(void)
prepare_for_output_pass (j_decompress_ptr cinfo)
{
my_master_ptr master = (my_master_ptr) cinfo->master;
if (master->pub.is_dummy_pass) {
#ifdef QUANT_2PASS_SUPPORTED
/* Final pass of 2-pass quantization */
master->pub.is_dummy_pass = FALSE;
(*cinfo->cquantize->start_pass) (cinfo, FALSE);
(*cinfo->post->start_pass) (cinfo, JBUF_CRANK_DEST);
(*cinfo->main->start_pass) (cinfo, JBUF_CRANK_DEST);
#else
ERREXIT(cinfo, JERR_NOT_COMPILED);
#endif /* QUANT_2PASS_SUPPORTED */
} else {
if (cinfo->quantize_colors && cinfo->colormap == NULL) {
/* Select new quantization method */
if (cinfo->two_pass_quantize && cinfo->enable_2pass_quant) {
cinfo->cquantize = master->quantizer_2pass;
master->pub.is_dummy_pass = TRUE;
} else if (cinfo->enable_1pass_quant) {
cinfo->cquantize = master->quantizer_1pass;
} else {
ERREXIT(cinfo, JERR_MODE_CHANGE);
}
}
(*cinfo->idct->start_pass) (cinfo);
(*cinfo->coef->start_output_pass) (cinfo);
if (! cinfo->raw_data_out) {
if (! master->using_merged_upsample)
(*cinfo->cconvert->start_pass) (cinfo);
(*cinfo->upsample->start_pass) (cinfo);
if (cinfo->quantize_colors)
(*cinfo->cquantize->start_pass) (cinfo, master->pub.is_dummy_pass);
(*cinfo->post->start_pass) (cinfo,
(master->pub.is_dummy_pass ? JBUF_SAVE_AND_PASS : JBUF_PASS_THRU));
(*cinfo->main->start_pass) (cinfo, JBUF_PASS_THRU);
}
}
/* Set up progress monitor's pass info if present */
if (cinfo->progress != NULL) {
cinfo->progress->completed_passes = master->pass_number;
cinfo->progress->total_passes = master->pass_number +
(master->pub.is_dummy_pass ? 2 : 1);
/* In buffered-image mode, we assume one more output pass if EOI not
* yet reached, but no more passes if EOI has been reached.
*/
if (cinfo->buffered_image && ! cinfo->inputctl->eoi_reached) {
cinfo->progress->total_passes += (cinfo->enable_2pass_quant ? 2 : 1);
}
}
}
/*
* Finish up at end of an output pass.
*/
METHODDEF(void)
finish_output_pass (j_decompress_ptr cinfo)
{
my_master_ptr master = (my_master_ptr) cinfo->master;
if (cinfo->quantize_colors)
(*cinfo->cquantize->finish_pass) (cinfo);
master->pass_number++;
}
#ifdef D_MULTISCAN_FILES_SUPPORTED
/*
* Switch to a new external colormap between output passes.
*/
GLOBAL(void)
jpeg_new_colormap (j_decompress_ptr cinfo)
{
my_master_ptr master = (my_master_ptr) cinfo->master;
/* Prevent application from calling me at wrong times */
if (cinfo->global_state != DSTATE_BUFIMAGE)
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
if (cinfo->quantize_colors && cinfo->enable_external_quant &&
cinfo->colormap != NULL) {
/* Select 2-pass quantizer for external colormap use */
cinfo->cquantize = master->quantizer_2pass;
/* Notify quantizer of colormap change */
(*cinfo->cquantize->new_color_map) (cinfo);
master->pub.is_dummy_pass = FALSE; /* just in case */
} else
ERREXIT(cinfo, JERR_MODE_CHANGE);
}
#endif /* D_MULTISCAN_FILES_SUPPORTED */
/*
* Initialize master decompression control and select active modules.
* This is performed at the start of jpeg_start_decompress.
*/
GLOBAL(void)
jinit_master_decompress (j_decompress_ptr cinfo)
{
my_master_ptr master;
master = (my_master_ptr)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
SIZEOF(my_decomp_master));
cinfo->master = (struct jpeg_decomp_master *) master;
master->pub.prepare_for_output_pass = prepare_for_output_pass;
master->pub.finish_output_pass = finish_output_pass;
master->pub.is_dummy_pass = FALSE;
master_selection(cinfo);
}
dlib/external/libjpeg/jdmerge.cpp 0 → 100644
View file @ 7cd5f664
/*
* jdmerge.c
*
* Copyright (C) 1994-1996, Thomas G. Lane.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file contains code for merged upsampling/color conversion.
*
* This file combines functions from jdsample.c and jdcolor.c;
* read those files first to understand what's going on.
*
* When the chroma components are to be upsampled by simple replication
* (ie, box filtering), we can save some work in color conversion by
* calculating all the output pixels corresponding to a pair of chroma
* samples at one time. In the conversion equations
* R = Y + K1 * Cr
* G = Y + K2 * Cb + K3 * Cr
* B = Y + K4 * Cb
* only the Y term varies among the group of pixels corresponding to a pair
* of chroma samples, so the rest of the terms can be calculated just once.
* At typical sampling ratios, this eliminates half or three-quarters of the
* multiplications needed for color conversion.
*
* This file currently provides implementations for the following cases:
* YCbCr => RGB color conversion only.
* Sampling ratios of 2h1v or 2h2v.
* No scaling needed at upsample time.
* Corner-aligned (non-CCIR601) sampling alignment.
* Other special cases could be added, but in most applications these are
* the only common cases. (For uncommon cases we fall back on the more
* general code in jdsample.c and jdcolor.c.)
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
#ifdef UPSAMPLE_MERGING_SUPPORTED
/* Private subobject */
typedef struct {
struct jpeg_upsampler pub; /* public fields */
/* Pointer to routine to do actual upsampling/conversion of one row group */
JMETHOD(void, upmethod, (j_decompress_ptr cinfo,
JSAMPIMAGE input_buf, JDIMENSION in_row_group_ctr,
JSAMPARRAY output_buf));
/* Private state for YCC->RGB conversion */
int * Cr_r_tab; /* => table for Cr to R conversion */
int * Cb_b_tab; /* => table for Cb to B conversion */
INT32 * Cr_g_tab; /* => table for Cr to G conversion */
INT32 * Cb_g_tab; /* => table for Cb to G conversion */
/* For 2:1 vertical sampling, we produce two output rows at a time.
* We need a "spare" row buffer to hold the second output row if the
* application provides just a one-row buffer; we also use the spare
* to discard the dummy last row if the image height is odd.
*/
JSAMPROW spare_row;
boolean spare_full; /* T if spare buffer is occupied */
JDIMENSION out_row_width; /* samples per output row */
JDIMENSION rows_to_go; /* counts rows remaining in image */
} my_upsampler;
typedef my_upsampler * my_upsample_ptr;
#define SCALEBITS 16 /* speediest right-shift on some machines */
#define ONE_HALF ((INT32) 1 << (SCALEBITS-1))
#define FIX(x) ((INT32) ((x) * (1L<<SCALEBITS) + 0.5))
/*
* Initialize tables for YCC->RGB colorspace conversion.
* This is taken directly from jdcolor.c; see that file for more info.
*/
LOCAL(void)
build_ycc_rgb_table (j_decompress_ptr cinfo)
{
my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;
int i;
INT32 x;
SHIFT_TEMPS
upsample->Cr_r_tab = (int *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
(MAXJSAMPLE+1) * SIZEOF(int));
upsample->Cb_b_tab = (int *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
(MAXJSAMPLE+1) * SIZEOF(int));
upsample->Cr_g_tab = (INT32 *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
(MAXJSAMPLE+1) * SIZEOF(INT32));
upsample->Cb_g_tab = (INT32 *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
(MAXJSAMPLE+1) * SIZEOF(INT32));
for (i = 0, x = -CENTERJSAMPLE; i <= MAXJSAMPLE; i++, x++) {
/* i is the actual input pixel value, in the range 0..MAXJSAMPLE */
/* The Cb or Cr value we are thinking of is x = i - CENTERJSAMPLE */
/* Cr=>R value is nearest int to 1.40200 * x */
upsample->Cr_r_tab[i] = (int)
RIGHT_SHIFT(FIX(1.40200) * x + ONE_HALF, SCALEBITS);
/* Cb=>B value is nearest int to 1.77200 * x */
upsample->Cb_b_tab[i] = (int)
RIGHT_SHIFT(FIX(1.77200) * x + ONE_HALF, SCALEBITS);
/* Cr=>G value is scaled-up -0.71414 * x */
upsample->Cr_g_tab[i] = (- FIX(0.71414)) * x;
/* Cb=>G value is scaled-up -0.34414 * x */
/* We also add in ONE_HALF so that need not do it in inner loop */
upsample->Cb_g_tab[i] = (- FIX(0.34414)) * x + ONE_HALF;
}
}
/*
* Initialize for an upsampling pass.
*/
METHODDEF(void)
start_pass_merged_upsample (j_decompress_ptr cinfo)
{
my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;
/* Mark the spare buffer empty */
upsample->spare_full = FALSE;
/* Initialize total-height counter for detecting bottom of image */
upsample->rows_to_go = cinfo->output_height;
}
/*
* Control routine to do upsampling (and color conversion).
*
* The control routine just handles the row buffering considerations.
*/
METHODDEF(void)
merged_2v_upsample (j_decompress_ptr cinfo,
JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr,
JDIMENSION in_row_groups_avail,
JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
JDIMENSION out_rows_avail)
/* 2:1 vertical sampling case: may need a spare row. */
{
my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;
JSAMPROW work_ptrs[2];
JDIMENSION num_rows; /* number of rows returned to caller */
if (upsample->spare_full) {
/* If we have a spare row saved from a previous cycle, just return it. */
jcopy_sample_rows(& upsample->spare_row, 0, output_buf + *out_row_ctr, 0,
1, upsample->out_row_width);
num_rows = 1;
upsample->spare_full = FALSE;
} else {
/* Figure number of rows to return to caller. */
num_rows = 2;
/* Not more than the distance to the end of the image. */
if (num_rows > upsample->rows_to_go)
num_rows = upsample->rows_to_go;
/* And not more than what the client can accept: */
out_rows_avail -= *out_row_ctr;
if (num_rows > out_rows_avail)
num_rows = out_rows_avail;
/* Create output pointer array for upsampler. */
work_ptrs[0] = output_buf[*out_row_ctr];
if (num_rows > 1) {
work_ptrs[1] = output_buf[*out_row_ctr + 1];
} else {
work_ptrs[1] = upsample->spare_row;
upsample->spare_full = TRUE;
}
/* Now do the upsampling. */
(*upsample->upmethod) (cinfo, input_buf, *in_row_group_ctr, work_ptrs);
}
/* Adjust counts */
*out_row_ctr += num_rows;
upsample->rows_to_go -= num_rows;
/* When the buffer is emptied, declare this input row group consumed */
if (! upsample->spare_full)
(*in_row_group_ctr)++;
}
METHODDEF(void)
merged_1v_upsample (j_decompress_ptr cinfo,
JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr,
JDIMENSION in_row_groups_avail,
JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
JDIMENSION out_rows_avail)
/* 1:1 vertical sampling case: much easier, never need a spare row. */
{
my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;
/* Just do the upsampling. */
(*upsample->upmethod) (cinfo, input_buf, *in_row_group_ctr,
output_buf + *out_row_ctr);
/* Adjust counts */
(*out_row_ctr)++;
(*in_row_group_ctr)++;
}
/*
* These are the routines invoked by the control routines to do
* the actual upsampling/conversion. One row group is processed per call.
*
* Note: since we may be writing directly into application-supplied buffers,
* we have to be honest about the output width; we can't assume the buffer
* has been rounded up to an even width.
*/
/*
* Upsample and color convert for the case of 2:1 horizontal and 1:1 vertical.
*/
METHODDEF(void)
h2v1_merged_upsample (j_decompress_ptr cinfo,
JSAMPIMAGE input_buf, JDIMENSION in_row_group_ctr,
JSAMPARRAY output_buf)
{
my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;
register int y, cred, cgreen, cblue;
int cb, cr;
register JSAMPROW outptr;
JSAMPROW inptr0, inptr1, inptr2;
JDIMENSION col;
/* copy these pointers into registers if possible */
register JSAMPLE * range_limit = cinfo->sample_range_limit;
int * Crrtab = upsample->Cr_r_tab;
int * Cbbtab = upsample->Cb_b_tab;
INT32 * Crgtab = upsample->Cr_g_tab;
INT32 * Cbgtab = upsample->Cb_g_tab;
SHIFT_TEMPS
inptr0 = input_buf[0][in_row_group_ctr];
inptr1 = input_buf[1][in_row_group_ctr];
inptr2 = input_buf[2][in_row_group_ctr];
outptr = output_buf[0];
/* Loop for each pair of output pixels */
for (col = cinfo->output_width >> 1; col > 0; col--) {
/* Do the chroma part of the calculation */
cb = GETJSAMPLE(*inptr1++);
cr = GETJSAMPLE(*inptr2++);
cred = Crrtab[cr];
cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS);
cblue = Cbbtab[cb];
/* Fetch 2 Y values and emit 2 pixels */
y = GETJSAMPLE(*inptr0++);
outptr[RGB_RED] = range_limit[y + cred];
outptr[RGB_GREEN] = range_limit[y + cgreen];
outptr[RGB_BLUE] = range_limit[y + cblue];
outptr += RGB_PIXELSIZE;
y = GETJSAMPLE(*inptr0++);
outptr[RGB_RED] = range_limit[y + cred];
outptr[RGB_GREEN] = range_limit[y + cgreen];
outptr[RGB_BLUE] = range_limit[y + cblue];
outptr += RGB_PIXELSIZE;
}
/* If image width is odd, do the last output column separately */
if (cinfo->output_width & 1) {
cb = GETJSAMPLE(*inptr1);
cr = GETJSAMPLE(*inptr2);
cred = Crrtab[cr];
cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS);
cblue = Cbbtab[cb];
y = GETJSAMPLE(*inptr0);
outptr[RGB_RED] = range_limit[y + cred];
outptr[RGB_GREEN] = range_limit[y + cgreen];
outptr[RGB_BLUE] = range_limit[y + cblue];
}
}
/*
* Upsample and color convert for the case of 2:1 horizontal and 2:1 vertical.
*/
METHODDEF(void)
h2v2_merged_upsample (j_decompress_ptr cinfo,
JSAMPIMAGE input_buf, JDIMENSION in_row_group_ctr,
JSAMPARRAY output_buf)
{
my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;
register int y, cred, cgreen, cblue;
int cb, cr;
register JSAMPROW outptr0, outptr1;
JSAMPROW inptr00, inptr01, inptr1, inptr2;
JDIMENSION col;
/* copy these pointers into registers if possible */
register JSAMPLE * range_limit = cinfo->sample_range_limit;
int * Crrtab = upsample->Cr_r_tab;
int * Cbbtab = upsample->Cb_b_tab;
INT32 * Crgtab = upsample->Cr_g_tab;
INT32 * Cbgtab = upsample->Cb_g_tab;
SHIFT_TEMPS
inptr00 = input_buf[0][in_row_group_ctr*2];
inptr01 = input_buf[0][in_row_group_ctr*2 + 1];
inptr1 = input_buf[1][in_row_group_ctr];
inptr2 = input_buf[2][in_row_group_ctr];
outptr0 = output_buf[0];
outptr1 = output_buf[1];
/* Loop for each group of output pixels */
for (col = cinfo->output_width >> 1; col > 0; col--) {
/* Do the chroma part of the calculation */
cb = GETJSAMPLE(*inptr1++);
cr = GETJSAMPLE(*inptr2++);
cred = Crrtab[cr];
cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS);
cblue = Cbbtab[cb];
/* Fetch 4 Y values and emit 4 pixels */
y = GETJSAMPLE(*inptr00++);
outptr0[RGB_RED] = range_limit[y + cred];
outptr0[RGB_GREEN] = range_limit[y + cgreen];
outptr0[RGB_BLUE] = range_limit[y + cblue];
outptr0 += RGB_PIXELSIZE;
y = GETJSAMPLE(*inptr00++);
outptr0[RGB_RED] = range_limit[y + cred];
outptr0[RGB_GREEN] = range_limit[y + cgreen];
outptr0[RGB_BLUE] = range_limit[y + cblue];
outptr0 += RGB_PIXELSIZE;
y = GETJSAMPLE(*inptr01++);
outptr1[RGB_RED] = range_limit[y + cred];
outptr1[RGB_GREEN] = range_limit[y + cgreen];
outptr1[RGB_BLUE] = range_limit[y + cblue];
outptr1 += RGB_PIXELSIZE;
y = GETJSAMPLE(*inptr01++);
outptr1[RGB_RED] = range_limit[y + cred];
outptr1[RGB_GREEN] = range_limit[y + cgreen];
outptr1[RGB_BLUE] = range_limit[y + cblue];
outptr1 += RGB_PIXELSIZE;
}
/* If image width is odd, do the last output column separately */
if (cinfo->output_width & 1) {
cb = GETJSAMPLE(*inptr1);
cr = GETJSAMPLE(*inptr2);
cred = Crrtab[cr];
cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS);
cblue = Cbbtab[cb];
y = GETJSAMPLE(*inptr00);
outptr0[RGB_RED] = range_limit[y + cred];
outptr0[RGB_GREEN] = range_limit[y + cgreen];
outptr0[RGB_BLUE] = range_limit[y + cblue];
y = GETJSAMPLE(*inptr01);
outptr1[RGB_RED] = range_limit[y + cred];
outptr1[RGB_GREEN] = range_limit[y + cgreen];
outptr1[RGB_BLUE] = range_limit[y + cblue];
}
}
/*
* Module initialization routine for merged upsampling/color conversion.
*
* NB: this is called under the conditions determined by use_merged_upsample()
* in jdmaster.c. That routine MUST correspond to the actual capabilities
* of this module; no safety checks are made here.
*/
GLOBAL(void)
jinit_merged_upsampler (j_decompress_ptr cinfo)
{
my_upsample_ptr upsample;
upsample = (my_upsample_ptr)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
SIZEOF(my_upsampler));
cinfo->upsample = (struct jpeg_upsampler *) upsample;
upsample->pub.start_pass = start_pass_merged_upsample;
upsample->pub.need_context_rows = FALSE;
upsample->out_row_width = cinfo->output_width * cinfo->out_color_components;
if (cinfo->max_v_samp_factor == 2) {
upsample->pub.upsample = merged_2v_upsample;
upsample->upmethod = h2v2_merged_upsample;
/* Allocate a spare row buffer */
upsample->spare_row = (JSAMPROW)
(*cinfo->mem->alloc_large) ((j_common_ptr) cinfo, JPOOL_IMAGE,
(size_t) (upsample->out_row_width * SIZEOF(JSAMPLE)));
} else {
upsample->pub.upsample = merged_1v_upsample;
upsample->upmethod = h2v1_merged_upsample;
/* No spare row needed */
upsample->spare_row = NULL;
}
build_ycc_rgb_table(cinfo);
}
#endif /* UPSAMPLE_MERGING_SUPPORTED */
dlib/external/libjpeg/jdphuff.cpp 0 → 100644
View file @ 7cd5f664
/*
* jdphuff.c
*
* Copyright (C) 1995-1997, Thomas G. Lane.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file contains Huffman entropy decoding routines for progressive JPEG.
*
* Much of the complexity here has to do with supporting input suspension.
* If the data source module demands suspension, we want to be able to back
* up to the start of the current MCU. To do this, we copy state variables
* into local working storage, and update them back to the permanent
* storage only upon successful completion of an MCU.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
#include "jdhuff.h" /* Declarations shared with jdhuff.c */
#ifdef D_PROGRESSIVE_SUPPORTED
/*
* Expanded entropy decoder object for progressive Huffman decoding.
*
* The savable_state subrecord contains fields that change within an MCU,
* but must not be updated permanently until we complete the MCU.
*/
typedef struct {
unsigned int EOBRUN; /* remaining EOBs in EOBRUN */
int last_dc_val[MAX_COMPS_IN_SCAN]; /* last DC coef for each component */
} savable_state;
/* This macro is to work around compilers with missing or broken
* structure assignment. You'll need to fix this code if you have
* such a compiler and you change MAX_COMPS_IN_SCAN.
*/
#ifndef NO_STRUCT_ASSIGN
#define ASSIGN_STATE(dest,src) ((dest) = (src))
#else
#if MAX_COMPS_IN_SCAN == 4
#define ASSIGN_STATE(dest,src) \
((dest).EOBRUN = (src).EOBRUN, \
(dest).last_dc_val[0] = (src).last_dc_val[0], \
(dest).last_dc_val[1] = (src).last_dc_val[1], \
(dest).last_dc_val[2] = (src).last_dc_val[2], \
(dest).last_dc_val[3] = (src).last_dc_val[3])
#endif
#endif
typedef struct {
struct jpeg_entropy_decoder pub; /* public fields */
/* These fields are loaded into local variables at start of each MCU.
* In case of suspension, we exit WITHOUT updating them.
*/
bitread_perm_state bitstate; /* Bit buffer at start of MCU */
savable_state saved; /* Other state at start of MCU */
/* These fields are NOT loaded into local working state. */
unsigned int restarts_to_go; /* MCUs left in this restart interval */
/* Pointers to derived tables (these workspaces have image lifespan) */
d_derived_tbl * derived_tbls[NUM_HUFF_TBLS];
d_derived_tbl * ac_derived_tbl; /* active table during an AC scan */
} phuff_entropy_decoder;
typedef phuff_entropy_decoder * phuff_entropy_ptr;
/* Forward declarations */
METHODDEF(boolean) decode_mcu_DC_first JPP((j_decompress_ptr cinfo,
JBLOCKROW *MCU_data));
METHODDEF(boolean) decode_mcu_AC_first JPP((j_decompress_ptr cinfo,
JBLOCKROW *MCU_data));
METHODDEF(boolean) decode_mcu_DC_refine JPP((j_decompress_ptr cinfo,
JBLOCKROW *MCU_data));
METHODDEF(boolean) decode_mcu_AC_refine JPP((j_decompress_ptr cinfo,
JBLOCKROW *MCU_data));
/*
* Initialize for a Huffman-compressed scan.
*/
METHODDEF(void)
start_pass_phuff_decoder (j_decompress_ptr cinfo)
{
phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
boolean is_DC_band, bad;
int ci, coefi, tbl;
int *coef_bit_ptr;
jpeg_component_info * compptr;
is_DC_band = (cinfo->Ss == 0);
/* Validate scan parameters */
bad = FALSE;
if (is_DC_band) {
if (cinfo->Se != 0)
bad = TRUE;
} else {
/* need not check Ss/Se < 0 since they came from unsigned bytes */
if (cinfo->Ss > cinfo->Se || cinfo->Se >= DCTSIZE2)
bad = TRUE;
/* AC scans may have only one component */
if (cinfo->comps_in_scan != 1)
bad = TRUE;
}
if (cinfo->Ah != 0) {
/* Successive approximation refinement scan: must have Al = Ah-1. */
if (cinfo->Al != cinfo->Ah-1)
bad = TRUE;
}
if (cinfo->Al > 13) /* need not check for < 0 */
bad = TRUE;
/* Arguably the maximum Al value should be less than 13 for 8-bit precision,
* but the spec doesn't say so, and we try to be liberal about what we
* accept. Note: large Al values could result in out-of-range DC
* coefficients during early scans, leading to bizarre displays due to
* overflows in the IDCT math. But we won't crash.
*/
if (bad)
ERREXIT4(cinfo, JERR_BAD_PROGRESSION,
cinfo->Ss, cinfo->Se, cinfo->Ah, cinfo->Al);
/* Update progression status, and verify that scan order is legal.
* Note that inter-scan inconsistencies are treated as warnings
* not fatal errors ... not clear if this is right way to behave.
*/
for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
int cindex = cinfo->cur_comp_info[ci]->component_index;
coef_bit_ptr = & cinfo->coef_bits[cindex][0];
if (!is_DC_band && coef_bit_ptr[0] < 0) /* AC without prior DC scan */
WARNMS2(cinfo, JWRN_BOGUS_PROGRESSION, cindex, 0);
for (coefi = cinfo->Ss; coefi <= cinfo->Se; coefi++) {
int expected = (coef_bit_ptr[coefi] < 0) ? 0 : coef_bit_ptr[coefi];
if (cinfo->Ah != expected)
WARNMS2(cinfo, JWRN_BOGUS_PROGRESSION, cindex, coefi);
coef_bit_ptr[coefi] = cinfo->Al;
}
}
/* Select MCU decoding routine */
if (cinfo->Ah == 0) {
if (is_DC_band)
entropy->pub.decode_mcu = decode_mcu_DC_first;
else
entropy->pub.decode_mcu = decode_mcu_AC_first;
} else {
if (is_DC_band)
entropy->pub.decode_mcu = decode_mcu_DC_refine;
else
entropy->pub.decode_mcu = decode_mcu_AC_refine;
}
for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
compptr = cinfo->cur_comp_info[ci];
/* Make sure requested tables are present, and compute derived tables.
* We may build same derived table more than once, but it's not expensive.
*/
if (is_DC_band) {
if (cinfo->Ah == 0) { /* DC refinement needs no table */
tbl = compptr->dc_tbl_no;
jpeg_make_d_derived_tbl(cinfo, TRUE, tbl,
& entropy->derived_tbls[tbl]);
}
} else {
tbl = compptr->ac_tbl_no;
jpeg_make_d_derived_tbl(cinfo, FALSE, tbl,
& entropy->derived_tbls[tbl]);
/* remember the single active table */
entropy->ac_derived_tbl = entropy->derived_tbls[tbl];
}
/* Initialize DC predictions to 0 */
entropy->saved.last_dc_val[ci] = 0;
}
/* Initialize bitread state variables */
entropy->bitstate.bits_left = 0;
entropy->bitstate.get_buffer = 0; /* unnecessary, but keeps Purify quiet */
entropy->pub.insufficient_data = FALSE;
/* Initialize private state variables */
entropy->saved.EOBRUN = 0;
/* Initialize restart counter */
entropy->restarts_to_go = cinfo->restart_interval;
}
/*
* Figure F.12: extend sign bit.
* On some machines, a shift and add will be faster than a table lookup.
*/
#ifdef AVOID_TABLES
#define HUFF_EXTEND(x,s) ((x) < (1<<((s)-1)) ? (x) + (((-1)<<(s)) + 1) : (x))
#else
#define HUFF_EXTEND(x,s) ((x) < extend_test[s] ? (x) + extend_offset[s] : (x))
static const int extend_test[16] = /* entry n is 2**(n-1) */
{ 0, 0x0001, 0x0002, 0x0004, 0x0008, 0x0010, 0x0020, 0x0040, 0x0080,
0x0100, 0x0200, 0x0400, 0x0800, 0x1000, 0x2000, 0x4000 };
static const int extend_offset[16] = /* entry n is (-1 << n) + 1 */
{ 0, ((-1)<<1) + 1, ((-1)<<2) + 1, ((-1)<<3) + 1, ((-1)<<4) + 1,
((-1)<<5) + 1, ((-1)<<6) + 1, ((-1)<<7) + 1, ((-1)<<8) + 1,
((-1)<<9) + 1, ((-1)<<10) + 1, ((-1)<<11) + 1, ((-1)<<12) + 1,
((-1)<<13) + 1, ((-1)<<14) + 1, ((-1)<<15) + 1 };
#endif /* AVOID_TABLES */
/*
* Check for a restart marker & resynchronize decoder.
* Returns FALSE if must suspend.
*/
LOCAL(boolean)
process_restart (j_decompress_ptr cinfo)
{
phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
int ci;
/* Throw away any unused bits remaining in bit buffer; */
/* include any full bytes in next_marker's count of discarded bytes */
cinfo->marker->discarded_bytes += entropy->bitstate.bits_left / 8;
entropy->bitstate.bits_left = 0;
/* Advance past the RSTn marker */
if (! (*cinfo->marker->read_restart_marker) (cinfo))
return FALSE;
/* Re-initialize DC predictions to 0 */
for (ci = 0; ci < cinfo->comps_in_scan; ci++)
entropy->saved.last_dc_val[ci] = 0;
/* Re-init EOB run count, too */
entropy->saved.EOBRUN = 0;
/* Reset restart counter */
entropy->restarts_to_go = cinfo->restart_interval;
/* Reset out-of-data flag, unless read_restart_marker left us smack up
* against a marker. In that case we will end up treating the next data
* segment as empty, and we can avoid producing bogus output pixels by
* leaving the flag set.
*/
if (cinfo->unread_marker == 0)
entropy->pub.insufficient_data = FALSE;
return TRUE;
}
/*
* Huffman MCU decoding.
* Each of these routines decodes and returns one MCU's worth of
* Huffman-compressed coefficients.
* The coefficients are reordered from zigzag order into natural array order,
* but are not dequantized.
*
* The i'th block of the MCU is stored into the block pointed to by
* MCU_data[i]. WE ASSUME THIS AREA IS INITIALLY ZEROED BY THE CALLER.
*
* We return FALSE if data source requested suspension. In that case no
* changes have been made to permanent state. (Exception: some output
* coefficients may already have been assigned. This is harmless for
* spectral selection, since we'll just re-assign them on the next call.
* Successive approximation AC refinement has to be more careful, however.)
*/
/*
* MCU decoding for DC initial scan (either spectral selection,
* or first pass of successive approximation).
*/
METHODDEF(boolean)
decode_mcu_DC_first (j_decompress_ptr cinfo, JBLOCKROW *MCU_data)
{
phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
int Al = cinfo->Al;
register int s, r;
int blkn, ci;
JBLOCKROW block;
BITREAD_STATE_VARS;
savable_state state;
d_derived_tbl * tbl;
jpeg_component_info * compptr;
/* Process restart marker if needed; may have to suspend */
if (cinfo->restart_interval) {
if (entropy->restarts_to_go == 0)
if (! process_restart(cinfo))
return FALSE;
}
/* If we've run out of data, just leave the MCU set to zeroes.
* This way, we return uniform gray for the remainder of the segment.
*/
if (! entropy->pub.insufficient_data) {
/* Load up working state */
BITREAD_LOAD_STATE(cinfo,entropy->bitstate);
ASSIGN_STATE(state, entropy->saved);
/* Outer loop handles each block in the MCU */
for (blkn = 0; blkn < cinfo->blocks_in_MCU; blkn++) {
block = MCU_data[blkn];
ci = cinfo->MCU_membership[blkn];
compptr = cinfo->cur_comp_info[ci];
tbl = entropy->derived_tbls[compptr->dc_tbl_no];
/* Decode a single block's worth of coefficients */
/* Section F.2.2.1: decode the DC coefficient difference */
HUFF_DECODE(s, br_state, tbl, return FALSE, label1);
if (s) {
CHECK_BIT_BUFFER(br_state, s, return FALSE);
r = GET_BITS(s);
s = HUFF_EXTEND(r, s);
}
/* Convert DC difference to actual value, update last_dc_val */
s += state.last_dc_val[ci];
state.last_dc_val[ci] = s;
/* Scale and output the coefficient (assumes jpeg_natural_order[0]=0) */
(*block)[0] = (JCOEF) (s << Al);
}
/* Completed MCU, so update state */
BITREAD_SAVE_STATE(cinfo,entropy->bitstate);
ASSIGN_STATE(entropy->saved, state);
}
/* Account for restart interval (no-op if not using restarts) */
entropy->restarts_to_go--;
return TRUE;
}
/*
* MCU decoding for AC initial scan (either spectral selection,
* or first pass of successive approximation).
*/
METHODDEF(boolean)
decode_mcu_AC_first (j_decompress_ptr cinfo, JBLOCKROW *MCU_data)
{
phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
int Se = cinfo->Se;
int Al = cinfo->Al;
register int s, k, r;
unsigned int EOBRUN;
JBLOCKROW block;
BITREAD_STATE_VARS;
d_derived_tbl * tbl;
/* Process restart marker if needed; may have to suspend */
if (cinfo->restart_interval) {
if (entropy->restarts_to_go == 0)
if (! process_restart(cinfo))
return FALSE;
}
/* If we've run out of data, just leave the MCU set to zeroes.
* This way, we return uniform gray for the remainder of the segment.
*/
if (! entropy->pub.insufficient_data) {
/* Load up working state.
* We can avoid loading/saving bitread state if in an EOB run.
*/
EOBRUN = entropy->saved.EOBRUN; /* only part of saved state we need */
/* There is always only one block per MCU */
if (EOBRUN > 0) /* if it's a band of zeroes... */
EOBRUN--; /* ...process it now (we do nothing) */
else {
BITREAD_LOAD_STATE(cinfo,entropy->bitstate);
block = MCU_data[0];
tbl = entropy->ac_derived_tbl;
for (k = cinfo->Ss; k <= Se; k++) {
HUFF_DECODE(s, br_state, tbl, return FALSE, label2);
r = s >> 4;
s &= 15;
if (s) {
k += r;
CHECK_BIT_BUFFER(br_state, s, return FALSE);
r = GET_BITS(s);
s = HUFF_EXTEND(r, s);
/* Scale and output coefficient in natural (dezigzagged) order */
(*block)[jpeg_natural_order[k]] = (JCOEF) (s << Al);
} else {
if (r == 15) { /* ZRL */
k += 15; /* skip 15 zeroes in band */
} else { /* EOBr, run length is 2^r + appended bits */
EOBRUN = 1 << r;
if (r) { /* EOBr, r > 0 */
CHECK_BIT_BUFFER(br_state, r, return FALSE);
r = GET_BITS(r);
EOBRUN += r;
}
EOBRUN--; /* this band is processed at this moment */
break; /* force end-of-band */
}
}
}
BITREAD_SAVE_STATE(cinfo,entropy->bitstate);
}
/* Completed MCU, so update state */
entropy->saved.EOBRUN = EOBRUN; /* only part of saved state we need */
}
/* Account for restart interval (no-op if not using restarts) */
entropy->restarts_to_go--;
return TRUE;
}
/*
* MCU decoding for DC successive approximation refinement scan.
* Note: we assume such scans can be multi-component, although the spec
* is not very clear on the point.
*/
METHODDEF(boolean)
decode_mcu_DC_refine (j_decompress_ptr cinfo, JBLOCKROW *MCU_data)
{
phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
int p1 = 1 << cinfo->Al; /* 1 in the bit position being coded */
int blkn;
JBLOCKROW block;
BITREAD_STATE_VARS;
/* Process restart marker if needed; may have to suspend */
if (cinfo->restart_interval) {
if (entropy->restarts_to_go == 0)
if (! process_restart(cinfo))
return FALSE;
}
/* Not worth the cycles to check insufficient_data here,
* since we will not change the data anyway if we read zeroes.
*/
/* Load up working state */
BITREAD_LOAD_STATE(cinfo,entropy->bitstate);
/* Outer loop handles each block in the MCU */
for (blkn = 0; blkn < cinfo->blocks_in_MCU; blkn++) {
block = MCU_data[blkn];
/* Encoded data is simply the next bit of the two's-complement DC value */
CHECK_BIT_BUFFER(br_state, 1, return FALSE);
if (GET_BITS(1))
(*block)[0] |= p1;
/* Note: since we use |=, repeating the assignment later is safe */
}
/* Completed MCU, so update state */
BITREAD_SAVE_STATE(cinfo,entropy->bitstate);
/* Account for restart interval (no-op if not using restarts) */
entropy->restarts_to_go--;
return TRUE;
}
/*
* MCU decoding for AC successive approximation refinement scan.
*/
METHODDEF(boolean)
decode_mcu_AC_refine (j_decompress_ptr cinfo, JBLOCKROW *MCU_data)
{
phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
int Se = cinfo->Se;
int p1 = 1 << cinfo->Al; /* 1 in the bit position being coded */
int m1 = (-1) << cinfo->Al; /* -1 in the bit position being coded */
register int s, k, r;
unsigned int EOBRUN;
JBLOCKROW block;
JCOEFPTR thiscoef;
BITREAD_STATE_VARS;
d_derived_tbl * tbl;
int num_newnz;
int newnz_pos[DCTSIZE2];
/* Process restart marker if needed; may have to suspend */
if (cinfo->restart_interval) {
if (entropy->restarts_to_go == 0)
if (! process_restart(cinfo))
return FALSE;
}
/* If we've run out of data, don't modify the MCU.
*/
if (! entropy->pub.insufficient_data) {
/* Load up working state */
BITREAD_LOAD_STATE(cinfo,entropy->bitstate);
EOBRUN = entropy->saved.EOBRUN; /* only part of saved state we need */
/* There is always only one block per MCU */
block = MCU_data[0];
tbl = entropy->ac_derived_tbl;
/* If we are forced to suspend, we must undo the assignments to any newly
* nonzero coefficients in the block, because otherwise we'd get confused
* next time about which coefficients were already nonzero.
* But we need not undo addition of bits to already-nonzero coefficients;
* instead, we can test the current bit to see if we already did it.
*/
num_newnz = 0;
/* initialize coefficient loop counter to start of band */
k = cinfo->Ss;
if (EOBRUN == 0) {
for (; k <= Se; k++) {
HUFF_DECODE(s, br_state, tbl, goto undoit, label3);
r = s >> 4;
s &= 15;
if (s) {
if (s != 1) /* size of new coef should always be 1 */
WARNMS(cinfo, JWRN_HUFF_BAD_CODE);
CHECK_BIT_BUFFER(br_state, 1, goto undoit);
if (GET_BITS(1))
s = p1; /* newly nonzero coef is positive */
else
s = m1; /* newly nonzero coef is negative */
} else {
if (r != 15) {
EOBRUN = 1 << r; /* EOBr, run length is 2^r + appended bits */
if (r) {
CHECK_BIT_BUFFER(br_state, r, goto undoit);
r = GET_BITS(r);
EOBRUN += r;
}
break; /* rest of block is handled by EOB logic */
}
/* note s = 0 for processing ZRL */
}
/* Advance over already-nonzero coefs and r still-zero coefs,
* appending correction bits to the nonzeroes. A correction bit is 1
* if the absolute value of the coefficient must be increased.
*/
do {
thiscoef = *block + jpeg_natural_order[k];
if (*thiscoef != 0) {
CHECK_BIT_BUFFER(br_state, 1, goto undoit);
if (GET_BITS(1)) {
if ((*thiscoef & p1) == 0) { /* do nothing if already set it */
if (*thiscoef >= 0)
*thiscoef += p1;
else
*thiscoef += m1;
}
}
} else {
if (--r < 0)
break; /* reached target zero coefficient */
}
k++;
} while (k <= Se);
if (s) {
int pos = jpeg_natural_order[k];
/* Output newly nonzero coefficient */
(*block)[pos] = (JCOEF) s;
/* Remember its position in case we have to suspend */
newnz_pos[num_newnz++] = pos;
}
}
}
if (EOBRUN > 0) {
/* Scan any remaining coefficient positions after the end-of-band
* (the last newly nonzero coefficient, if any). Append a correction
* bit to each already-nonzero coefficient. A correction bit is 1
* if the absolute value of the coefficient must be increased.
*/
for (; k <= Se; k++) {
thiscoef = *block + jpeg_natural_order[k];
if (*thiscoef != 0) {
CHECK_BIT_BUFFER(br_state, 1, goto undoit);
if (GET_BITS(1)) {
if ((*thiscoef & p1) == 0) { /* do nothing if already changed it */
if (*thiscoef >= 0)
*thiscoef += p1;
else
*thiscoef += m1;
}
}
}
}
/* Count one block completed in EOB run */
EOBRUN--;
}
/* Completed MCU, so update state */
BITREAD_SAVE_STATE(cinfo,entropy->bitstate);
entropy->saved.EOBRUN = EOBRUN; /* only part of saved state we need */
}
/* Account for restart interval (no-op if not using restarts) */
entropy->restarts_to_go--;
return TRUE;
undoit:
/* Re-zero any output coefficients that we made newly nonzero */
while (num_newnz > 0)
(*block)[newnz_pos[--num_newnz]] = 0;
return FALSE;
}
/*
* Module initialization routine for progressive Huffman entropy decoding.
*/
GLOBAL(void)
jinit_phuff_decoder (j_decompress_ptr cinfo)
{
phuff_entropy_ptr entropy;
int *coef_bit_ptr;
int ci, i;
entropy = (phuff_entropy_ptr)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
SIZEOF(phuff_entropy_decoder));
cinfo->entropy = (struct jpeg_entropy_decoder *) entropy;
entropy->pub.start_pass = start_pass_phuff_decoder;
/* Mark derived tables unallocated */
for (i = 0; i < NUM_HUFF_TBLS; i++) {
entropy->derived_tbls[i] = NULL;
}
/* Create progression status table */
cinfo->coef_bits = (int (*)[DCTSIZE2])
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
cinfo->num_components*DCTSIZE2*SIZEOF(int));
coef_bit_ptr = & cinfo->coef_bits[0][0];
for (ci = 0; ci < cinfo->num_components; ci++)
for (i = 0; i < DCTSIZE2; i++)
*coef_bit_ptr++ = -1;
}
#endif /* D_PROGRESSIVE_SUPPORTED */
dlib/external/libjpeg/jdpostct.cpp 0 → 100644
View file @ 7cd5f664
/*
* jdpostct.c
*
* Copyright (C) 1994-1996, Thomas G. Lane.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file contains the decompression postprocessing controller.
* This controller manages the upsampling, color conversion, and color
* quantization/reduction steps; specifically, it controls the buffering
* between upsample/color conversion and color quantization/reduction.
*
* If no color quantization/reduction is required, then this module has no
* work to do, and it just hands off to the upsample/color conversion code.
* An integrated upsample/convert/quantize process would replace this module
* entirely.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
/* Private buffer controller object */
typedef struct {
struct jpeg_d_post_controller pub; /* public fields */
/* Color quantization source buffer: this holds output data from
* the upsample/color conversion step to be passed to the quantizer.
* For two-pass color quantization, we need a full-image buffer;
* for one-pass operation, a strip buffer is sufficient.
*/
jvirt_sarray_ptr whole_image; /* virtual array, or NULL if one-pass */
JSAMPARRAY buffer; /* strip buffer, or current strip of virtual */
JDIMENSION strip_height; /* buffer size in rows */
/* for two-pass mode only: */
JDIMENSION starting_row; /* row # of first row in current strip */
JDIMENSION next_row; /* index of next row to fill/empty in strip */
} my_post_controller;
typedef my_post_controller * my_post_ptr;
/* Forward declarations */
METHODDEF(void) post_process_1pass
JPP((j_decompress_ptr cinfo,
JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr,
JDIMENSION in_row_groups_avail,
JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
JDIMENSION out_rows_avail));
#ifdef QUANT_2PASS_SUPPORTED
METHODDEF(void) post_process_prepass
JPP((j_decompress_ptr cinfo,
JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr,
JDIMENSION in_row_groups_avail,
JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
JDIMENSION out_rows_avail));
METHODDEF(void) post_process_2pass
JPP((j_decompress_ptr cinfo,
JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr,
JDIMENSION in_row_groups_avail,
JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
JDIMENSION out_rows_avail));
#endif
/*
* Initialize for a processing pass.
*/
METHODDEF(void)
start_pass_dpost (j_decompress_ptr cinfo, J_BUF_MODE pass_mode)
{
my_post_ptr post = (my_post_ptr) cinfo->post;
switch (pass_mode) {
case JBUF_PASS_THRU:
if (cinfo->quantize_colors) {
/* Single-pass processing with color quantization. */
post->pub.post_process_data = post_process_1pass;
/* We could be doing buffered-image output before starting a 2-pass
* color quantization; in that case, jinit_d_post_controller did not
* allocate a strip buffer. Use the virtual-array buffer as workspace.
*/
if (post->buffer == NULL) {
post->buffer = (*cinfo->mem->access_virt_sarray)
((j_common_ptr) cinfo, post->whole_image,
(JDIMENSION) 0, post->strip_height, TRUE);
}
} else {
/* For single-pass processing without color quantization,
* I have no work to do; just call the upsampler directly.
*/
post->pub.post_process_data = cinfo->upsample->upsample;
}
break;
#ifdef QUANT_2PASS_SUPPORTED
case JBUF_SAVE_AND_PASS:
/* First pass of 2-pass quantization */
if (post->whole_image == NULL)
ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
post->pub.post_process_data = post_process_prepass;
break;
case JBUF_CRANK_DEST:
/* Second pass of 2-pass quantization */
if (post->whole_image == NULL)
ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
post->pub.post_process_data = post_process_2pass;
break;
#endif /* QUANT_2PASS_SUPPORTED */
default:
ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
break;
}
post->starting_row = post->next_row = 0;
}
/*
* Process some data in the one-pass (strip buffer) case.
* This is used for color precision reduction as well as one-pass quantization.
*/
METHODDEF(void)
post_process_1pass (j_decompress_ptr cinfo,
JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr,
JDIMENSION in_row_groups_avail,
JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
JDIMENSION out_rows_avail)
{
my_post_ptr post = (my_post_ptr) cinfo->post;
JDIMENSION num_rows, max_rows;
/* Fill the buffer, but not more than what we can dump out in one go. */
/* Note we rely on the upsampler to detect bottom of image. */
max_rows = out_rows_avail - *out_row_ctr;
if (max_rows > post->strip_height)
max_rows = post->strip_height;
num_rows = 0;
(*cinfo->upsample->upsample) (cinfo,
input_buf, in_row_group_ctr, in_row_groups_avail,
post->buffer, &num_rows, max_rows);
/* Quantize and emit data. */
(*cinfo->cquantize->color_quantize) (cinfo,
post->buffer, output_buf + *out_row_ctr, (int) num_rows);
*out_row_ctr += num_rows;
}
#ifdef QUANT_2PASS_SUPPORTED
/*
* Process some data in the first pass of 2-pass quantization.
*/
METHODDEF(void)
post_process_prepass (j_decompress_ptr cinfo,
JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr,
JDIMENSION in_row_groups_avail,
JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
JDIMENSION out_rows_avail)
{
my_post_ptr post = (my_post_ptr) cinfo->post;
JDIMENSION old_next_row, num_rows;
/* Reposition virtual buffer if at start of strip. */
if (post->next_row == 0) {
post->buffer = (*cinfo->mem->access_virt_sarray)
((j_common_ptr) cinfo, post->whole_image,
post->starting_row, post->strip_height, TRUE);
}
/* Upsample some data (up to a strip height's worth). */
old_next_row = post->next_row;
(*cinfo->upsample->upsample) (cinfo,
input_buf, in_row_group_ctr, in_row_groups_avail,
post->buffer, &post->next_row, post->strip_height);
/* Allow quantizer to scan new data. No data is emitted, */
/* but we advance out_row_ctr so outer loop can tell when we're done. */
if (post->next_row > old_next_row) {
num_rows = post->next_row - old_next_row;
(*cinfo->cquantize->color_quantize) (cinfo, post->buffer + old_next_row,
(JSAMPARRAY) NULL, (int) num_rows);
*out_row_ctr += num_rows;
}
/* Advance if we filled the strip. */
if (post->next_row >= post->strip_height) {
post->starting_row += post->strip_height;
post->next_row = 0;
}
}
/*
* Process some data in the second pass of 2-pass quantization.
*/
METHODDEF(void)
post_process_2pass (j_decompress_ptr cinfo,
JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr,
JDIMENSION in_row_groups_avail,
JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
JDIMENSION out_rows_avail)
{
my_post_ptr post = (my_post_ptr) cinfo->post;
JDIMENSION num_rows, max_rows;
/* Reposition virtual buffer if at start of strip. */
if (post->next_row == 0) {
post->buffer = (*cinfo->mem->access_virt_sarray)
((j_common_ptr) cinfo, post->whole_image,
post->starting_row, post->strip_height, FALSE);
}
/* Determine number of rows to emit. */
num_rows = post->strip_height - post->next_row; /* available in strip */
max_rows = out_rows_avail - *out_row_ctr; /* available in output area */
if (num_rows > max_rows)
num_rows = max_rows;
/* We have to check bottom of image here, can't depend on upsampler. */
max_rows = cinfo->output_height - post->starting_row;
if (num_rows > max_rows)
num_rows = max_rows;
/* Quantize and emit data. */
(*cinfo->cquantize->color_quantize) (cinfo,
post->buffer + post->next_row, output_buf + *out_row_ctr,
(int) num_rows);
*out_row_ctr += num_rows;
/* Advance if we filled the strip. */
post->next_row += num_rows;
if (post->next_row >= post->strip_height) {
post->starting_row += post->strip_height;
post->next_row = 0;
}
}
#endif /* QUANT_2PASS_SUPPORTED */
/*
* Initialize postprocessing controller.
*/
GLOBAL(void)
jinit_d_post_controller (j_decompress_ptr cinfo, boolean need_full_buffer)
{
my_post_ptr post;
post = (my_post_ptr)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
SIZEOF(my_post_controller));
cinfo->post = (struct jpeg_d_post_controller *) post;
post->pub.start_pass = start_pass_dpost;
post->whole_image = NULL; /* flag for no virtual arrays */
post->buffer = NULL; /* flag for no strip buffer */
/* Create the quantization buffer, if needed */
if (cinfo->quantize_colors) {
/* The buffer strip height is max_v_samp_factor, which is typically
* an efficient number of rows for upsampling to return.
* (In the presence of output rescaling, we might want to be smarter?)
*/
post->strip_height = (JDIMENSION) cinfo->max_v_samp_factor;
if (need_full_buffer) {
/* Two-pass color quantization: need full-image storage. */
/* We round up the number of rows to a multiple of the strip height. */
#ifdef QUANT_2PASS_SUPPORTED
post->whole_image = (*cinfo->mem->request_virt_sarray)
((j_common_ptr) cinfo, JPOOL_IMAGE, FALSE,
cinfo->output_width * cinfo->out_color_components,
(JDIMENSION) jround_up((long) cinfo->output_height,
(long) post->strip_height),
post->strip_height);
#else
ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
#endif /* QUANT_2PASS_SUPPORTED */
} else {
/* One-pass color quantization: just make a strip buffer. */
post->buffer = (*cinfo->mem->alloc_sarray)
((j_common_ptr) cinfo, JPOOL_IMAGE,
cinfo->output_width * cinfo->out_color_components,
post->strip_height);
}
}
}
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