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Commit 747088ea authored by Davis King's avatar Davis King
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Added save_jpeg()

parent 3bef1e6b
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dlib/CMakeLists.txt
View file @ 747088ea
...@@ -294,10 +294,30 @@ if (NOT TARGET dlib) ...@@ -294,10 +294,30 @@ if (NOT TARGET dlib)
external/libjpeg/jmemnobs.cpp external/libjpeg/jmemnobs.cpp
external/libjpeg/jquant1.cpp external/libjpeg/jquant1.cpp
external/libjpeg/jquant2.cpp external/libjpeg/jquant2.cpp
external/libjpeg/jutils.cpp ) external/libjpeg/jutils.cpp
external/libjpeg/jcapimin.cpp
external/libjpeg/jdatadst.cpp
external/libjpeg/jcparam.cpp
external/libjpeg/jcapistd.cpp
external/libjpeg/jcmarker.cpp
external/libjpeg/jcinit.cpp
external/libjpeg/jcmaster.cpp
external/libjpeg/jcdctmgr.cpp
external/libjpeg/jccoefct.cpp
external/libjpeg/jccolor.cpp
external/libjpeg/jchuff.cpp
external/libjpeg/jcmainct.cpp
external/libjpeg/jcphuff.cpp
external/libjpeg/jcprepct.cpp
external/libjpeg/jcsample.cpp
external/libjpeg/jfdctint.cpp
external/libjpeg/jfdctflt.cpp
external/libjpeg/jfdctfst.cpp
)
endif() endif()
set(source_files ${source_files} set(source_files ${source_files}
image_loader/jpeg_loader.cpp image_loader/jpeg_loader.cpp
image_saver/save_jpeg.cpp
) )
endif() endif()
......
dlib/all/source.cpp
View file @ 747088ea
...@@ -57,6 +57,7 @@ ...@@ -57,6 +57,7 @@
#ifdef DLIB_JPEG_SUPPORT #ifdef DLIB_JPEG_SUPPORT
#include "../image_loader/jpeg_loader.cpp" #include "../image_loader/jpeg_loader.cpp"
#include "../image_saver/save_jpeg.cpp"
#endif #endif
#ifndef DLIB_NO_GUI_SUPPORT #ifndef DLIB_NO_GUI_SUPPORT
......
dlib/external/libjpeg/jcapimin.cpp 0 → 100644
View file @ 747088ea
/*
* jcapimin.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 compression half
* of the JPEG library. These are the "minimum" API routines that may be
* needed in either the normal full-compression case or the transcoding-only
* case.
*
* Most of the routines intended to be called directly by an application
* are in this file or in jcapistd.c. But also see jcparam.c for
* parameter-setup helper routines, jcomapi.c for routines shared by
* compression and decompression, and jctrans.c for the transcoding case.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
/*
* Initialization of a JPEG compression object.
* The error manager must already be set up (in case memory manager fails).
*/
GLOBAL(void)
jpeg_CreateCompress (j_compress_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_compress_struct))
ERREXIT2(cinfo, JERR_BAD_STRUCT_SIZE,
(int) SIZEOF(struct jpeg_compress_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_compress_struct));
cinfo->err = err;
cinfo->client_data = client_data;
}
cinfo->is_decompressor = FALSE;
/* 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->dest = NULL;
cinfo->comp_info = 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;
}
cinfo->script_space = NULL;
cinfo->input_gamma = 1.0; /* in case application forgets */
/* OK, I'm ready */
cinfo->global_state = CSTATE_START;
}
/*
* Destruction of a JPEG compression object
*/
GLOBAL(void)
jpeg_destroy_compress (j_compress_ptr cinfo)
{
jpeg_destroy((j_common_ptr) cinfo); /* use common routine */
}
/*
* Abort processing of a JPEG compression operation,
* but don't destroy the object itself.
*/
GLOBAL(void)
jpeg_abort_compress (j_compress_ptr cinfo)
{
jpeg_abort((j_common_ptr) cinfo); /* use common routine */
}
/*
* Forcibly suppress or un-suppress all quantization and Huffman tables.
* Marks all currently defined tables as already written (if suppress)
* or not written (if !suppress). This will control whether they get emitted
* by a subsequent jpeg_start_compress call.
*
* This routine is exported for use by applications that want to produce
* abbreviated JPEG datastreams. It logically belongs in jcparam.c, but
* since it is called by jpeg_start_compress, we put it here --- otherwise
* jcparam.o would be linked whether the application used it or not.
*/
GLOBAL(void)
jpeg_suppress_tables (j_compress_ptr cinfo, int suppress)
{
int i;
JQUANT_TBL * qtbl;
JHUFF_TBL * htbl;
for (i = 0; i < NUM_QUANT_TBLS; i++) {
if ((qtbl = cinfo->quant_tbl_ptrs[i]) != NULL)
qtbl->sent_table = suppress;
}
for (i = 0; i < NUM_HUFF_TBLS; i++) {
if ((htbl = cinfo->dc_huff_tbl_ptrs[i]) != NULL)
htbl->sent_table = suppress;
if ((htbl = cinfo->ac_huff_tbl_ptrs[i]) != NULL)
htbl->sent_table = suppress;
}
}
/*
* Finish JPEG compression.
*
* If a multipass operating mode was selected, this may do a great deal of
* work including most of the actual output.
*/
GLOBAL(void)
jpeg_finish_compress (j_compress_ptr cinfo)
{
JDIMENSION iMCU_row;
if (cinfo->global_state == CSTATE_SCANNING ||
cinfo->global_state == CSTATE_RAW_OK) {
/* Terminate first pass */
if (cinfo->next_scanline < cinfo->image_height)
ERREXIT(cinfo, JERR_TOO_LITTLE_DATA);
(*cinfo->master->finish_pass) (cinfo);
} else if (cinfo->global_state != CSTATE_WRCOEFS)
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
/* Perform any remaining passes */
while (! cinfo->master->is_last_pass) {
(*cinfo->master->prepare_for_pass) (cinfo);
for (iMCU_row = 0; iMCU_row < cinfo->total_iMCU_rows; iMCU_row++) {
if (cinfo->progress != NULL) {
cinfo->progress->pass_counter = (long) iMCU_row;
cinfo->progress->pass_limit = (long) cinfo->total_iMCU_rows;
(*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);
}
/* We bypass the main controller and invoke coef controller directly;
* all work is being done from the coefficient buffer.
*/
if (! (*cinfo->coef->compress_data) (cinfo, (JSAMPIMAGE) NULL))
ERREXIT(cinfo, JERR_CANT_SUSPEND);
}
(*cinfo->master->finish_pass) (cinfo);
}
/* Write EOI, do final cleanup */
(*cinfo->marker->write_file_trailer) (cinfo);
(*cinfo->dest->term_destination) (cinfo);
/* We can use jpeg_abort to release memory and reset global_state */
jpeg_abort((j_common_ptr) cinfo);
}
/*
* Write a special marker.
* This is only recommended for writing COM or APPn markers.
* Must be called after jpeg_start_compress() and before
* first call to jpeg_write_scanlines() or jpeg_write_raw_data().
*/
GLOBAL(void)
jpeg_write_marker (j_compress_ptr cinfo, int marker,
const JOCTET *dataptr, unsigned int datalen)
{
JMETHOD(void, write_marker_byte, (j_compress_ptr info, int val));
if (cinfo->next_scanline != 0 ||
(cinfo->global_state != CSTATE_SCANNING &&
cinfo->global_state != CSTATE_RAW_OK &&
cinfo->global_state != CSTATE_WRCOEFS))
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
(*cinfo->marker->write_marker_header) (cinfo, marker, datalen);
write_marker_byte = cinfo->marker->write_marker_byte; /* copy for speed */
while (datalen--) {
(*write_marker_byte) (cinfo, *dataptr);
dataptr++;
}
}
/* Same, but piecemeal. */
GLOBAL(void)
jpeg_write_m_header (j_compress_ptr cinfo, int marker, unsigned int datalen)
{
if (cinfo->next_scanline != 0 ||
(cinfo->global_state != CSTATE_SCANNING &&
cinfo->global_state != CSTATE_RAW_OK &&
cinfo->global_state != CSTATE_WRCOEFS))
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
(*cinfo->marker->write_marker_header) (cinfo, marker, datalen);
}
GLOBAL(void)
jpeg_write_m_byte (j_compress_ptr cinfo, int val)
{
(*cinfo->marker->write_marker_byte) (cinfo, val);
}
/*
* Alternate compression function: just write an abbreviated table file.
* Before calling this, all parameters and a data destination must be set up.
*
* To produce a pair of files containing abbreviated tables and abbreviated
* image data, one would proceed as follows:
*
* initialize JPEG object
* set JPEG parameters
* set destination to table file
* jpeg_write_tables(cinfo);
* set destination to image file
* jpeg_start_compress(cinfo, FALSE);
* write data...
* jpeg_finish_compress(cinfo);
*
* jpeg_write_tables has the side effect of marking all tables written
* (same as jpeg_suppress_tables(..., TRUE)). Thus a subsequent start_compress
* will not re-emit the tables unless it is passed write_all_tables=TRUE.
*/
GLOBAL(void)
jpeg_write_tables (j_compress_ptr cinfo)
{
if (cinfo->global_state != CSTATE_START)
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
/* (Re)initialize error mgr and destination modules */
(*cinfo->err->reset_error_mgr) ((j_common_ptr) cinfo);
(*cinfo->dest->init_destination) (cinfo);
/* Initialize the marker writer ... bit of a crock to do it here. */
jinit_marker_writer(cinfo);
/* Write them tables! */
(*cinfo->marker->write_tables_only) (cinfo);
/* And clean up. */
(*cinfo->dest->term_destination) (cinfo);
/*
* In library releases up through v6a, we called jpeg_abort() here to free
* any working memory allocated by the destination manager and marker
* writer. Some applications had a problem with that: they allocated space
* of their own from the library memory manager, and didn't want it to go
* away during write_tables. So now we do nothing. This will cause a
* memory leak if an app calls write_tables repeatedly without doing a full
* compression cycle or otherwise resetting the JPEG object. However, that
* seems less bad than unexpectedly freeing memory in the normal case.
* An app that prefers the old behavior can call jpeg_abort for itself after
* each call to jpeg_write_tables().
*/
}
dlib/external/libjpeg/jcapistd.cpp 0 → 100644
View file @ 747088ea
/*
* jcapistd.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 compression half
* of the JPEG library. These are the "standard" API routines that are
* used in the normal full-compression case. They are not used by a
* transcoding-only application. Note that if an application links in
* jpeg_start_compress, it will end up linking in the entire compressor.
* We thus must separate this file from jcapimin.c to avoid linking the
* whole compression library into a transcoder.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
/*
* Compression initialization.
* Before calling this, all parameters and a data destination must be set up.
*
* We require a write_all_tables parameter as a failsafe check when writing
* multiple datastreams from the same compression object. Since prior runs
* will have left all the tables marked sent_table=TRUE, a subsequent run
* would emit an abbreviated stream (no tables) by default. This may be what
* is wanted, but for safety's sake it should not be the default behavior:
* programmers should have to make a deliberate choice to emit abbreviated
* images. Therefore the documentation and examples should encourage people
* to pass write_all_tables=TRUE; then it will take active thought to do the
* wrong thing.
*/
GLOBAL(void)
jpeg_start_compress (j_compress_ptr cinfo, int write_all_tables)
{
if (cinfo->global_state != CSTATE_START)
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
if (write_all_tables)
jpeg_suppress_tables(cinfo, FALSE); /* mark all tables to be written */
/* (Re)initialize error mgr and destination modules */
(*cinfo->err->reset_error_mgr) ((j_common_ptr) cinfo);
(*cinfo->dest->init_destination) (cinfo);
/* Perform master selection of active modules */
jinit_compress_master(cinfo);
/* Set up for the first pass */
(*cinfo->master->prepare_for_pass) (cinfo);
/* Ready for application to drive first pass through jpeg_write_scanlines
* or jpeg_write_raw_data.
*/
cinfo->next_scanline = 0;
cinfo->global_state = (cinfo->raw_data_in ? CSTATE_RAW_OK : CSTATE_SCANNING);
}
/*
* Write some scanlines of data to the JPEG compressor.
*
* The return value will be the number of lines actually written.
* This should be less than the supplied num_lines only in case that
* the data destination module has requested suspension of the compressor,
* or if more than image_height scanlines are passed in.
*
* Note: we warn about excess calls to jpeg_write_scanlines() since
* this likely signals an application programmer error. However,
* excess scanlines passed in the last valid call are *silently* ignored,
* so that the application need not adjust num_lines for end-of-image
* when using a multiple-scanline buffer.
*/
GLOBAL(JDIMENSION)
jpeg_write_scanlines (j_compress_ptr cinfo, JSAMPARRAY scanlines,
JDIMENSION num_lines)
{
JDIMENSION row_ctr, rows_left;
if (cinfo->global_state != CSTATE_SCANNING)
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
if (cinfo->next_scanline >= cinfo->image_height)
WARNMS(cinfo, JWRN_TOO_MUCH_DATA);
/* Call progress monitor hook if present */
if (cinfo->progress != NULL) {
cinfo->progress->pass_counter = (long) cinfo->next_scanline;
cinfo->progress->pass_limit = (long) cinfo->image_height;
(*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);
}
/* Give master control module another chance if this is first call to
* jpeg_write_scanlines. This lets output of the frame/scan headers be
* delayed so that application can write COM, etc, markers between
* jpeg_start_compress and jpeg_write_scanlines.
*/
if (cinfo->master->call_pass_startup)
(*cinfo->master->pass_startup) (cinfo);
/* Ignore any extra scanlines at bottom of image. */
rows_left = cinfo->image_height - cinfo->next_scanline;
if (num_lines > rows_left)
num_lines = rows_left;
row_ctr = 0;
(*cinfo->main->process_data) (cinfo, scanlines, &row_ctr, num_lines);
cinfo->next_scanline += row_ctr;
return row_ctr;
}
/*
* Alternate entry point to write raw data.
* Processes exactly one iMCU row per call, unless suspended.
*/
GLOBAL(JDIMENSION)
jpeg_write_raw_data (j_compress_ptr cinfo, JSAMPIMAGE data,
JDIMENSION num_lines)
{
JDIMENSION lines_per_iMCU_row;
if (cinfo->global_state != CSTATE_RAW_OK)
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
if (cinfo->next_scanline >= cinfo->image_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->next_scanline;
cinfo->progress->pass_limit = (long) cinfo->image_height;
(*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);
}
/* Give master control module another chance if this is first call to
* jpeg_write_raw_data. This lets output of the frame/scan headers be
* delayed so that application can write COM, etc, markers between
* jpeg_start_compress and jpeg_write_raw_data.
*/
if (cinfo->master->call_pass_startup)
(*cinfo->master->pass_startup) (cinfo);
/* Verify that at least one iMCU row has been passed. */
lines_per_iMCU_row = cinfo->max_v_samp_factor * DCTSIZE;
if (num_lines < lines_per_iMCU_row)
ERREXIT(cinfo, JERR_BUFFER_SIZE);
/* Directly compress the row. */
if (! (*cinfo->coef->compress_data) (cinfo, data)) {
/* If compressor did not consume the whole row, suspend processing. */
return 0;
}
/* OK, we processed one iMCU row. */
cinfo->next_scanline += lines_per_iMCU_row;
return lines_per_iMCU_row;
}
dlib/external/libjpeg/jccoefct.cpp 0 → 100644
View file @ 747088ea
/*
* jccoefct.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 compression.
* This controller is the top level of the JPEG compressor proper.
* The coefficient buffer lies between forward-DCT and entropy encoding steps.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
/* We use a full-image coefficient buffer when doing Huffman optimization,
* and also for writing multiple-scan JPEG files. In all cases, the DCT
* step is run during the first pass, and subsequent passes need only read
* the buffered coefficients.
*/
#ifdef ENTROPY_OPT_SUPPORTED
#define FULL_COEF_BUFFER_SUPPORTED
#else
#ifdef C_MULTISCAN_FILES_SUPPORTED
#define FULL_COEF_BUFFER_SUPPORTED
#endif
#endif
/* Private buffer controller object */
typedef struct {
struct jpeg_c_coef_controller pub; /* public fields */
JDIMENSION iMCU_row_num; /* iMCU row # within image */
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 */
/* For single-pass compression, it's sufficient to buffer just one MCU
* (although this may prove a bit slow in practice). We allocate a
* workspace of C_MAX_BLOCKS_IN_MCU coefficient blocks, and reuse it for each
* MCU constructed and sent. (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.
*/
JBLOCKROW MCU_buffer[C_MAX_BLOCKS_IN_MCU];
/* In multi-pass modes, we need a virtual block array for each component. */
jvirt_barray_ptr whole_image[MAX_COMPONENTS];
} my_coef_controller;
typedef my_coef_controller * my_coef_ptr;
/* Forward declarations */
METHODDEF(int) compress_data
JPP((j_compress_ptr cinfo, JSAMPIMAGE input_buf));
#ifdef FULL_COEF_BUFFER_SUPPORTED
METHODDEF(int) compress_first_pass
JPP((j_compress_ptr cinfo, JSAMPIMAGE input_buf));
METHODDEF(int) compress_output
JPP((j_compress_ptr cinfo, JSAMPIMAGE input_buf));
#endif
LOCAL(void)
start_iMCU_row (j_compress_ptr cinfo)
/* Reset within-iMCU-row counters for a new row */
{
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 (coef->iMCU_row_num < (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 a processing pass.
*/
METHODDEF(void)
start_pass_coef (j_compress_ptr cinfo, J_BUF_MODE pass_mode)
{
my_coef_ptr coef = (my_coef_ptr) cinfo->coef;
coef->iMCU_row_num = 0;
start_iMCU_row(cinfo);
switch (pass_mode) {
case JBUF_PASS_THRU:
if (coef->whole_image[0] != NULL)
ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
coef->pub.compress_data = compress_data;
break;
#ifdef FULL_COEF_BUFFER_SUPPORTED
case JBUF_SAVE_AND_PASS:
if (coef->whole_image[0] == NULL)
ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
coef->pub.compress_data = compress_first_pass;
break;
case JBUF_CRANK_DEST:
if (coef->whole_image[0] == NULL)
ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
coef->pub.compress_data = compress_output;
break;
#endif
default:
ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
break;
}
}
/*
* Process some data in the single-pass case.
* We process the equivalent of one fully interleaved MCU row ("iMCU" row)
* per call, ie, v_samp_factor block rows for each component in the image.
* Returns TRUE if the iMCU row is completed, FALSE if suspended.
*
* NB: input_buf contains a plane for each component in image,
* which we index according to the component's SOF position.
*/
METHODDEF(int)
compress_data (j_compress_ptr cinfo, JSAMPIMAGE input_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, bi, ci, yindex, yoffset, blockcnt;
JDIMENSION ypos, xpos;
jpeg_component_info *compptr;
/* Loop to write 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++) {
/* Determine where data comes from in input_buf and do the DCT thing.
* Each call on forward_DCT processes a horizontal row of DCT blocks
* as wide as an MCU; we rely on having allocated the MCU_buffer[] blocks
* sequentially. Dummy blocks at the right or bottom edge are filled in
* specially. The data in them does not matter for image reconstruction,
* so we fill them with values that will encode to the smallest amount of
* data, viz: all zeroes in the AC entries, DC entries equal to previous
* block's DC value. (Thanks to Thomas Kinsman for this idea.)
*/
blkn = 0;
for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
compptr = cinfo->cur_comp_info[ci];
blockcnt = (MCU_col_num < last_MCU_col) ? compptr->MCU_width
: compptr->last_col_width;
xpos = MCU_col_num * compptr->MCU_sample_width;
ypos = yoffset * DCTSIZE; /* ypos == (yoffset+yindex) * DCTSIZE */
for (yindex = 0; yindex < compptr->MCU_height; yindex++) {
if (coef->iMCU_row_num < last_iMCU_row ||
yoffset+yindex < compptr->last_row_height) {
(*cinfo->fdct->forward_DCT) (cinfo, compptr,
input_buf[compptr->component_index],
coef->MCU_buffer[blkn],
ypos, xpos, (JDIMENSION) blockcnt);
if (blockcnt < compptr->MCU_width) {
/* Create some dummy blocks at the right edge of the image. */
jzero_far((void FAR *) coef->MCU_buffer[blkn + blockcnt],
(compptr->MCU_width - blockcnt) * SIZEOF(JBLOCK));
for (bi = blockcnt; bi < compptr->MCU_width; bi++) {
coef->MCU_buffer[blkn+bi][0][0] = coef->MCU_buffer[blkn+bi-1][0][0];
}
}
} else {
/* Create a row of dummy blocks at the bottom of the image. */
jzero_far((void FAR *) coef->MCU_buffer[blkn],
compptr->MCU_width * SIZEOF(JBLOCK));
for (bi = 0; bi < compptr->MCU_width; bi++) {
coef->MCU_buffer[blkn+bi][0][0] = coef->MCU_buffer[blkn-1][0][0];
}
}
blkn += compptr->MCU_width;
ypos += DCTSIZE;
}
}
/* Try to write the MCU. In event of a suspension failure, we will
* re-DCT the MCU on restart (a bit inefficient, could be fixed...)
*/
if (! (*cinfo->entropy->encode_mcu) (cinfo, coef->MCU_buffer)) {
/* Suspension forced; update state counters and exit */
coef->MCU_vert_offset = yoffset;
coef->mcu_ctr = MCU_col_num;
return FALSE;
}
}
/* Completed an MCU row, but perhaps not an iMCU row */
coef->mcu_ctr = 0;
}
/* Completed the iMCU row, advance counters for next one */
coef->iMCU_row_num++;
start_iMCU_row(cinfo);
return TRUE;
}
#ifdef FULL_COEF_BUFFER_SUPPORTED
/*
* Process some data in the first pass of a multi-pass case.
* We process the equivalent of one fully interleaved MCU row ("iMCU" row)
* per call, ie, v_samp_factor block rows for each component in the image.
* This amount of data is read from the source buffer, DCT'd and quantized,
* and saved into the virtual arrays. We also generate suitable dummy blocks
* as needed at the right and lower edges. (The dummy blocks are constructed
* in the virtual arrays, which have been padded appropriately.) This makes
* it possible for subsequent passes not to worry about real vs. dummy blocks.
*
* We must also emit the data to the entropy encoder. This is conveniently
* done by calling compress_output() after we've loaded the current strip
* of the virtual arrays.
*
* NB: input_buf contains a plane for each component in image. All
* components are DCT'd and loaded into the virtual arrays in this pass.
* However, it may be that only a subset of the components are emitted to
* the entropy encoder during this first pass; be careful about looking
* at the scan-dependent variables (MCU dimensions, etc).
*/
METHODDEF(int)
compress_first_pass (j_compress_ptr cinfo, JSAMPIMAGE input_buf)
{
my_coef_ptr coef = (my_coef_ptr) cinfo->coef;
JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1;
JDIMENSION blocks_across, MCUs_across, MCUindex;
int bi, ci, h_samp_factor, block_row, block_rows, ndummy;
JCOEF lastDC;
jpeg_component_info *compptr;
JBLOCKARRAY buffer;
JBLOCKROW thisblockrow, lastblockrow;
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
/* Align the virtual buffer for this component. */
buffer = (*cinfo->mem->access_virt_barray)
((j_common_ptr) cinfo, coef->whole_image[ci],
coef->iMCU_row_num * compptr->v_samp_factor,
(JDIMENSION) compptr->v_samp_factor, TRUE);
/* Count non-dummy DCT block rows in this iMCU row. */
if (coef->iMCU_row_num < last_iMCU_row)
block_rows = compptr->v_samp_factor;
else {
/* NB: can't use last_row_height here, since may not be set! */
block_rows = (int) (compptr->height_in_blocks % compptr->v_samp_factor);
if (block_rows == 0) block_rows = compptr->v_samp_factor;
}
blocks_across = compptr->width_in_blocks;
h_samp_factor = compptr->h_samp_factor;
/* Count number of dummy blocks to be added at the right margin. */
ndummy = (int) (blocks_across % h_samp_factor);
if (ndummy > 0)
ndummy = h_samp_factor - ndummy;
/* Perform DCT for all non-dummy blocks in this iMCU row. Each call
* on forward_DCT processes a complete horizontal row of DCT blocks.
*/
for (block_row = 0; block_row < block_rows; block_row++) {
thisblockrow = buffer[block_row];
(*cinfo->fdct->forward_DCT) (cinfo, compptr,
input_buf[ci], thisblockrow,
(JDIMENSION) (block_row * DCTSIZE),
(JDIMENSION) 0, blocks_across);
if (ndummy > 0) {
/* Create dummy blocks at the right edge of the image. */
thisblockrow += blocks_across; /* => first dummy block */
jzero_far((void FAR *) thisblockrow, ndummy * SIZEOF(JBLOCK));
lastDC = thisblockrow[-1][0];
for (bi = 0; bi < ndummy; bi++) {
thisblockrow[bi][0] = lastDC;
}
}
}
/* If at end of image, create dummy block rows as needed.
* The tricky part here is that within each MCU, we want the DC values
* of the dummy blocks to match the last real block's DC value.
* This squeezes a few more bytes out of the resulting file...
*/
if (coef->iMCU_row_num == last_iMCU_row) {
blocks_across += ndummy; /* include lower right corner */
MCUs_across = blocks_across / h_samp_factor;
for (block_row = block_rows; block_row < compptr->v_samp_factor;
block_row++) {
thisblockrow = buffer[block_row];
lastblockrow = buffer[block_row-1];
jzero_far((void FAR *) thisblockrow,
(size_t) (blocks_across * SIZEOF(JBLOCK)));
for (MCUindex = 0; MCUindex < MCUs_across; MCUindex++) {
lastDC = lastblockrow[h_samp_factor-1][0];
for (bi = 0; bi < h_samp_factor; bi++) {
thisblockrow[bi][0] = lastDC;
}
thisblockrow += h_samp_factor; /* advance to next MCU in row */
lastblockrow += h_samp_factor;
}
}
}
}
/* NB: compress_output will increment iMCU_row_num if successful.
* A suspension return will result in redoing all the work above next time.
*/
/* Emit data to the entropy encoder, sharing code with subsequent passes */
return compress_output(cinfo, input_buf);
}
/*
* Process some data in subsequent passes of a multi-pass case.
* We process the equivalent of one fully interleaved MCU row ("iMCU" row)
* per call, ie, v_samp_factor block rows for each component in the scan.
* The data is obtained from the virtual arrays and fed to the entropy coder.
* Returns TRUE if the iMCU row is completed, FALSE if suspended.
*
* NB: input_buf is ignored; it is likely to be a NULL pointer.
*/
METHODDEF(int)
compress_output (j_compress_ptr cinfo, JSAMPIMAGE input_buf)
{
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.
* NB: during first pass, this is safe only because the buffers will
* already be aligned properly, so jmemmgr.c won't need to do any I/O.
*/
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],
coef->iMCU_row_num * compptr->v_samp_factor,
(JDIMENSION) compptr->v_samp_factor, FALSE);
}
/* 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 write the MCU. */
if (! (*cinfo->entropy->encode_mcu) (cinfo, coef->MCU_buffer)) {
/* Suspension forced; update state counters and exit */
coef->MCU_vert_offset = yoffset;
coef->mcu_ctr = MCU_col_num;
return FALSE;
}
}
/* Completed an MCU row, but perhaps not an iMCU row */
coef->mcu_ctr = 0;
}
/* Completed the iMCU row, advance counters for next one */
coef->iMCU_row_num++;
start_iMCU_row(cinfo);
return TRUE;
}
#endif /* FULL_COEF_BUFFER_SUPPORTED */
/*
* Initialize coefficient buffer controller.
*/
GLOBAL(void)
jinit_c_coef_controller (j_compress_ptr cinfo, int 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_c_coef_controller *) coef;
coef->pub.start_pass = start_pass_coef;
/* Create the coefficient buffer. */
if (need_full_buffer) {
#ifdef FULL_COEF_BUFFER_SUPPORTED
/* Allocate a full-image virtual array for each component, */
/* padded to a multiple of samp_factor DCT blocks in each direction. */
int ci;
jpeg_component_info *compptr;
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
coef->whole_image[ci] = (*cinfo->mem->request_virt_barray)
((j_common_ptr) cinfo, JPOOL_IMAGE, FALSE,
(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) compptr->v_samp_factor);
}
#else
ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
#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,
C_MAX_BLOCKS_IN_MCU * SIZEOF(JBLOCK));
for (i = 0; i < C_MAX_BLOCKS_IN_MCU; i++) {
coef->MCU_buffer[i] = buffer + i;
}
coef->whole_image[0] = NULL; /* flag for no virtual arrays */
}
}
dlib/external/libjpeg/jccolor.cpp 0 → 100644
View file @ 747088ea
/*
* jccolor.c
*
* Copyright (C) 1991-1996, 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 input colorspace conversion routines.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
/* Private subobject */
typedef struct {
struct jpeg_color_converter pub; /* public fields */
/* Private state for RGB->YCC conversion */
long * rgb_ycc_tab; /* => table for RGB to YCbCr conversion */
} my_color_converter;
typedef my_color_converter * my_cconvert_ptr;
/**************** RGB -> YCbCr 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
* Y = 0.29900 * R + 0.58700 * G + 0.11400 * B
* Cb = -0.16874 * R - 0.33126 * G + 0.50000 * B + CENTERJSAMPLE
* Cr = 0.50000 * R - 0.41869 * G - 0.08131 * B + CENTERJSAMPLE
* (These numbers are derived from TIFF 6.0 section 21, dated 3-June-92.)
* Note: older versions of the IJG code used a zero offset of MAXJSAMPLE/2,
* rather than CENTERJSAMPLE, for Cb and Cr. This gave equal positive and
* negative swings for Cb/Cr, but meant that grayscale values (Cb=Cr=0)
* were not represented exactly. Now we sacrifice exact representation of
* maximum red and maximum blue in order to get exact grayscales.
*
* 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.
*
* For even more speed, we avoid doing any multiplications in the inner loop
* by precalculating the constants times R,G,B 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 CENTERJSAMPLE offsets and the rounding fudge-factor of 0.5 are included
* in the tables to save adding them separately in the inner loop.
*/
#define SCALEBITS 16 /* speediest right-shift on some machines */
#define CBCR_OFFSET ((long) CENTERJSAMPLE << SCALEBITS)
#define ONE_HALF ((long) 1 << (SCALEBITS-1))
#define FIX(x) ((long) ((x) * (1L<<SCALEBITS) + 0.5))
/* We allocate one big table and divide it up into eight parts, instead of
* doing eight alloc_small requests. This lets us use a single table base
* address, which can be held in a register in the inner loops on many
* machines (more than can hold all eight addresses, anyway).
*/
#define R_Y_OFF 0 /* offset to R => Y section */
#define G_Y_OFF (1*(MAXJSAMPLE+1)) /* offset to G => Y section */
#define B_Y_OFF (2*(MAXJSAMPLE+1)) /* etc. */
#define R_CB_OFF (3*(MAXJSAMPLE+1))
#define G_CB_OFF (4*(MAXJSAMPLE+1))
#define B_CB_OFF (5*(MAXJSAMPLE+1))
#define R_CR_OFF B_CB_OFF /* B=>Cb, R=>Cr are the same */
#define G_CR_OFF (6*(MAXJSAMPLE+1))
#define B_CR_OFF (7*(MAXJSAMPLE+1))
#define TABLE_SIZE (8*(MAXJSAMPLE+1))
/*
* Initialize for RGB->YCC colorspace conversion.
*/
METHODDEF(void)
rgb_ycc_start (j_compress_ptr cinfo)
{
my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;
long * rgb_ycc_tab;
long i;
/* Allocate and fill in the conversion tables. */
cconvert->rgb_ycc_tab = rgb_ycc_tab = (long *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
(TABLE_SIZE * SIZEOF(long)));
for (i = 0; i <= MAXJSAMPLE; i++) {
rgb_ycc_tab[i+R_Y_OFF] = FIX(0.29900) * i;
rgb_ycc_tab[i+G_Y_OFF] = FIX(0.58700) * i;
rgb_ycc_tab[i+B_Y_OFF] = FIX(0.11400) * i + ONE_HALF;
rgb_ycc_tab[i+R_CB_OFF] = (-FIX(0.16874)) * i;
rgb_ycc_tab[i+G_CB_OFF] = (-FIX(0.33126)) * i;
/* We use a rounding fudge-factor of 0.5-epsilon for Cb and Cr.
* This ensures that the maximum output will round to MAXJSAMPLE
* not MAXJSAMPLE+1, and thus that we don't have to range-limit.
*/
rgb_ycc_tab[i+B_CB_OFF] = FIX(0.50000) * i + CBCR_OFFSET + ONE_HALF-1;
/* B=>Cb and R=>Cr tables are the same
rgb_ycc_tab[i+R_CR_OFF] = FIX(0.50000) * i + CBCR_OFFSET + ONE_HALF-1;
*/
rgb_ycc_tab[i+G_CR_OFF] = (-FIX(0.41869)) * i;
rgb_ycc_tab[i+B_CR_OFF] = (-FIX(0.08131)) * i;
}
}
/*
* Convert some rows of samples to the JPEG colorspace.
*
* Note that we change from the application's interleaved-pixel format
* to our internal noninterleaved, one-plane-per-component format.
* The input buffer is therefore three times as wide as the output buffer.
*
* A starting row offset is provided only for the output buffer. The caller
* can easily adjust the passed input_buf value to accommodate any row
* offset required on that side.
*/
METHODDEF(void)
rgb_ycc_convert (j_compress_ptr cinfo,
JSAMPARRAY input_buf, JSAMPIMAGE output_buf,
JDIMENSION output_row, int num_rows)
{
my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;
register int r, g, b;
register long * ctab = cconvert->rgb_ycc_tab;
register JSAMPROW inptr;
register JSAMPROW outptr0, outptr1, outptr2;
register JDIMENSION col;
JDIMENSION num_cols = cinfo->image_width;
while (--num_rows >= 0) {
inptr = *input_buf++;
outptr0 = output_buf[0][output_row];
outptr1 = output_buf[1][output_row];
outptr2 = output_buf[2][output_row];
output_row++;
for (col = 0; col < num_cols; col++) {
r = GETJSAMPLE(inptr[RGB_RED]);
g = GETJSAMPLE(inptr[RGB_GREEN]);
b = GETJSAMPLE(inptr[RGB_BLUE]);
inptr += RGB_PIXELSIZE;
/* If the inputs are 0..MAXJSAMPLE, the outputs of these equations
* must be too; we do not need an explicit range-limiting operation.
* Hence the value being shifted is never negative, and we don't
* need the general RIGHT_SHIFT macro.
*/
/* Y */
outptr0[col] = (JSAMPLE)
((ctab[r+R_Y_OFF] + ctab[g+G_Y_OFF] + ctab[b+B_Y_OFF])
>> SCALEBITS);
/* Cb */
outptr1[col] = (JSAMPLE)
((ctab[r+R_CB_OFF] + ctab[g+G_CB_OFF] + ctab[b+B_CB_OFF])
>> SCALEBITS);
/* Cr */
outptr2[col] = (JSAMPLE)
((ctab[r+R_CR_OFF] + ctab[g+G_CR_OFF] + ctab[b+B_CR_OFF])
>> SCALEBITS);
}
}
}
/**************** Cases other than RGB -> YCbCr **************/
/*
* Convert some rows of samples to the JPEG colorspace.
* This version handles RGB->grayscale conversion, which is the same
* as the RGB->Y portion of RGB->YCbCr.
* We assume rgb_ycc_start has been called (we only use the Y tables).
*/
METHODDEF(void)
rgb_gray_convert (j_compress_ptr cinfo,
JSAMPARRAY input_buf, JSAMPIMAGE output_buf,
JDIMENSION output_row, int num_rows)
{
my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;
register int r, g, b;
register long * ctab = cconvert->rgb_ycc_tab;
register JSAMPROW inptr;
register JSAMPROW outptr;
register JDIMENSION col;
JDIMENSION num_cols = cinfo->image_width;
while (--num_rows >= 0) {
inptr = *input_buf++;
outptr = output_buf[0][output_row];
output_row++;
for (col = 0; col < num_cols; col++) {
r = GETJSAMPLE(inptr[RGB_RED]);
g = GETJSAMPLE(inptr[RGB_GREEN]);
b = GETJSAMPLE(inptr[RGB_BLUE]);
inptr += RGB_PIXELSIZE;
/* Y */
outptr[col] = (JSAMPLE)
((ctab[r+R_Y_OFF] + ctab[g+G_Y_OFF] + ctab[b+B_Y_OFF])
>> SCALEBITS);
}
}
}
/*
* Convert some rows of samples to the JPEG colorspace.
* This version handles Adobe-style CMYK->YCCK conversion,
* where we convert R=1-C, G=1-M, and B=1-Y to YCbCr using the same
* conversion as above, while passing K (black) unchanged.
* We assume rgb_ycc_start has been called.
*/
METHODDEF(void)
cmyk_ycck_convert (j_compress_ptr cinfo,
JSAMPARRAY input_buf, JSAMPIMAGE output_buf,
JDIMENSION output_row, int num_rows)
{
my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;
register int r, g, b;
register long * ctab = cconvert->rgb_ycc_tab;
register JSAMPROW inptr;
register JSAMPROW outptr0, outptr1, outptr2, outptr3;
register JDIMENSION col;
JDIMENSION num_cols = cinfo->image_width;
while (--num_rows >= 0) {
inptr = *input_buf++;
outptr0 = output_buf[0][output_row];
outptr1 = output_buf[1][output_row];
outptr2 = output_buf[2][output_row];
outptr3 = output_buf[3][output_row];
output_row++;
for (col = 0; col < num_cols; col++) {
r = MAXJSAMPLE - GETJSAMPLE(inptr[0]);
g = MAXJSAMPLE - GETJSAMPLE(inptr[1]);
b = MAXJSAMPLE - GETJSAMPLE(inptr[2]);
/* K passes through as-is */
outptr3[col] = inptr[3]; /* don't need GETJSAMPLE here */
inptr += 4;
/* If the inputs are 0..MAXJSAMPLE, the outputs of these equations
* must be too; we do not need an explicit range-limiting operation.
* Hence the value being shifted is never negative, and we don't
* need the general RIGHT_SHIFT macro.
*/
/* Y */
outptr0[col] = (JSAMPLE)
((ctab[r+R_Y_OFF] + ctab[g+G_Y_OFF] + ctab[b+B_Y_OFF])
>> SCALEBITS);
/* Cb */
outptr1[col] = (JSAMPLE)
((ctab[r+R_CB_OFF] + ctab[g+G_CB_OFF] + ctab[b+B_CB_OFF])
>> SCALEBITS);
/* Cr */
outptr2[col] = (JSAMPLE)
((ctab[r+R_CR_OFF] + ctab[g+G_CR_OFF] + ctab[b+B_CR_OFF])
>> SCALEBITS);
}
}
}
/*
* Convert some rows of samples to the JPEG colorspace.
* This version handles grayscale output with no conversion.
* The source can be either plain grayscale or YCbCr (since Y == gray).
*/
METHODDEF(void)
grayscale_convert (j_compress_ptr cinfo,
JSAMPARRAY input_buf, JSAMPIMAGE output_buf,
JDIMENSION output_row, int num_rows)
{
register JSAMPROW inptr;
register JSAMPROW outptr;
register JDIMENSION col;
JDIMENSION num_cols = cinfo->image_width;
int instride = cinfo->input_components;
while (--num_rows >= 0) {
inptr = *input_buf++;
outptr = output_buf[0][output_row];
output_row++;
for (col = 0; col < num_cols; col++) {
outptr[col] = inptr[0]; /* don't need GETJSAMPLE() here */
inptr += instride;
}
}
}
/*
* Convert some rows of samples to the JPEG colorspace.
* This version handles multi-component colorspaces without conversion.
* We assume input_components == num_components.
*/
METHODDEF(void)
null_convert (j_compress_ptr cinfo,
JSAMPARRAY input_buf, JSAMPIMAGE output_buf,
JDIMENSION output_row, int num_rows)
{
register JSAMPROW inptr;
register JSAMPROW outptr;
register JDIMENSION col;
register int ci;
int nc = cinfo->num_components;
JDIMENSION num_cols = cinfo->image_width;
while (--num_rows >= 0) {
/* It seems fastest to make a separate pass for each component. */
for (ci = 0; ci < nc; ci++) {
inptr = *input_buf;
outptr = output_buf[ci][output_row];
for (col = 0; col < num_cols; col++) {
outptr[col] = inptr[ci]; /* don't need GETJSAMPLE() here */
inptr += nc;
}
}
input_buf++;
output_row++;
}
}
/*
* Empty method for start_pass.
*/
METHODDEF(void)
null_method (j_compress_ptr cinfo)
{
/* no work needed */
}
/*
* Module initialization routine for input colorspace conversion.
*/
GLOBAL(void)
jinit_color_converter (j_compress_ptr cinfo)
{
my_cconvert_ptr cconvert;
cconvert = (my_cconvert_ptr)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
SIZEOF(my_color_converter));
cinfo->cconvert = (struct jpeg_color_converter *) cconvert;
/* set start_pass to null method until we find out differently */
cconvert->pub.start_pass = null_method;
/* Make sure input_components agrees with in_color_space */
switch (cinfo->in_color_space) {
case JCS_GRAYSCALE:
if (cinfo->input_components != 1)
ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);
break;
case JCS_RGB:
#if RGB_PIXELSIZE != 3
if (cinfo->input_components != RGB_PIXELSIZE)
ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);
break;
#endif /* else share code with YCbCr */
case JCS_YCbCr:
if (cinfo->input_components != 3)
ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);
break;
case JCS_CMYK:
case JCS_YCCK:
if (cinfo->input_components != 4)
ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);
break;
default: /* JCS_UNKNOWN can be anything */
if (cinfo->input_components < 1)
ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);
break;
}
/* Check num_components, set conversion method based on requested space */
switch (cinfo->jpeg_color_space) {
case JCS_GRAYSCALE:
if (cinfo->num_components != 1)
ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);
if (cinfo->in_color_space == JCS_GRAYSCALE)
cconvert->pub.color_convert = grayscale_convert;
else if (cinfo->in_color_space == JCS_RGB) {
cconvert->pub.start_pass = rgb_ycc_start;
cconvert->pub.color_convert = rgb_gray_convert;
} else if (cinfo->in_color_space == JCS_YCbCr)
cconvert->pub.color_convert = grayscale_convert;
else
ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
break;
case JCS_RGB:
if (cinfo->num_components != 3)
ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);
if (cinfo->in_color_space == JCS_RGB && RGB_PIXELSIZE == 3)
cconvert->pub.color_convert = null_convert;
else
ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
break;
case JCS_YCbCr:
if (cinfo->num_components != 3)
ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);
if (cinfo->in_color_space == JCS_RGB) {
cconvert->pub.start_pass = rgb_ycc_start;
cconvert->pub.color_convert = rgb_ycc_convert;
} else if (cinfo->in_color_space == JCS_YCbCr)
cconvert->pub.color_convert = null_convert;
else
ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
break;
case JCS_CMYK:
if (cinfo->num_components != 4)
ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);
if (cinfo->in_color_space == JCS_CMYK)
cconvert->pub.color_convert = null_convert;
else
ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
break;
case JCS_YCCK:
if (cinfo->num_components != 4)
ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);
if (cinfo->in_color_space == JCS_CMYK) {
cconvert->pub.start_pass = rgb_ycc_start;
cconvert->pub.color_convert = cmyk_ycck_convert;
} else if (cinfo->in_color_space == JCS_YCCK)
cconvert->pub.color_convert = null_convert;
else
ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
break;
default: /* allow null conversion of JCS_UNKNOWN */
if (cinfo->jpeg_color_space != cinfo->in_color_space ||
cinfo->num_components != cinfo->input_components)
ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
cconvert->pub.color_convert = null_convert;
break;
}
}
dlib/external/libjpeg/jcdctmgr.cpp 0 → 100644
View file @ 747088ea
/*
* jcdctmgr.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 forward-DCT management logic.
* This code selects a particular DCT implementation to be used,
* and it performs related housekeeping chores including coefficient
* quantization.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
#include "jdct.h" /* Private declarations for DCT subsystem */
/* Private subobject for this module */
typedef struct {
struct jpeg_forward_dct pub; /* public fields */
/* Pointer to the DCT routine actually in use */
forward_DCT_method_ptr do_dct;
/* The actual post-DCT divisors --- not identical to the quant table
* entries, because of scaling (especially for an unnormalized DCT).
* Each table is given in normal array order.
*/
DCTELEM * divisors[NUM_QUANT_TBLS];
#ifdef DCT_FLOAT_SUPPORTED
/* Same as above for the floating-point case. */
float_DCT_method_ptr do_float_dct;
FAST_FLOAT * float_divisors[NUM_QUANT_TBLS];
#endif
} my_fdct_controller;
typedef my_fdct_controller * my_fdct_ptr;
/*
* Initialize for a processing pass.
* Verify that all referenced Q-tables are present, and set up
* the divisor table for each one.
* In the current implementation, DCT of all components is done during
* the first pass, even if only some components will be output in the
* first scan. Hence all components should be examined here.
*/
METHODDEF(void)
start_pass_fdctmgr (j_compress_ptr cinfo)
{
my_fdct_ptr fdct = (my_fdct_ptr) cinfo->fdct;
int ci, qtblno, i;
jpeg_component_info *compptr;
JQUANT_TBL * qtbl;
DCTELEM * dtbl;
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
qtblno = compptr->quant_tbl_no;
/* Make sure specified quantization table is present */
if (qtblno < 0 || qtblno >= NUM_QUANT_TBLS ||
cinfo->quant_tbl_ptrs[qtblno] == NULL)
ERREXIT1(cinfo, JERR_NO_QUANT_TABLE, qtblno);
qtbl = cinfo->quant_tbl_ptrs[qtblno];
/* Compute divisors for this quant table */
/* We may do this more than once for same table, but it's not a big deal */
switch (cinfo->dct_method) {
#ifdef DCT_ISLOW_SUPPORTED
case JDCT_ISLOW:
/* For LL&M IDCT method, divisors are equal to raw quantization
* coefficients multiplied by 8 (to counteract scaling).
*/
if (fdct->divisors[qtblno] == NULL) {
fdct->divisors[qtblno] = (DCTELEM *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
DCTSIZE2 * SIZEOF(DCTELEM));
}
dtbl = fdct->divisors[qtblno];
for (i = 0; i < DCTSIZE2; i++) {
dtbl[i] = ((DCTELEM) qtbl->quantval[i]) << 3;
}
break;
#endif
#ifdef DCT_IFAST_SUPPORTED
case JDCT_IFAST:
{
/* For AA&N IDCT method, divisors 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
* We apply a further scale factor of 8.
*/
#define CONST_BITS 14
static const short 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
if (fdct->divisors[qtblno] == NULL) {
fdct->divisors[qtblno] = (DCTELEM *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
DCTSIZE2 * SIZEOF(DCTELEM));
}
dtbl = fdct->divisors[qtblno];
for (i = 0; i < DCTSIZE2; i++) {
dtbl[i] = (DCTELEM)
DESCALE(MULTIPLY16V16((long) qtbl->quantval[i],
(long) aanscales[i]),
CONST_BITS-3);
}
}
break;
#endif
#ifdef DCT_FLOAT_SUPPORTED
case JDCT_FLOAT:
{
/* For float AA&N IDCT method, divisors 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
* We apply a further scale factor of 8.
* What's actually stored is 1/divisor so that the inner loop can
* use a multiplication rather than a division.
*/
FAST_FLOAT * fdtbl;
int row, col;
static const double aanscalefactor[DCTSIZE] = {
1.0, 1.387039845, 1.306562965, 1.175875602,
1.0, 0.785694958, 0.541196100, 0.275899379
};
if (fdct->float_divisors[qtblno] == NULL) {
fdct->float_divisors[qtblno] = (FAST_FLOAT *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
DCTSIZE2 * SIZEOF(FAST_FLOAT));
}
fdtbl = fdct->float_divisors[qtblno];
i = 0;
for (row = 0; row < DCTSIZE; row++) {
for (col = 0; col < DCTSIZE; col++) {
fdtbl[i] = (FAST_FLOAT)
(1.0 / (((double) qtbl->quantval[i] *
aanscalefactor[row] * aanscalefactor[col] * 8.0)));
i++;
}
}
}
break;
#endif
default:
ERREXIT(cinfo, JERR_NOT_COMPILED);
break;
}
}
}
/*
* Perform forward DCT on one or more blocks of a component.
*
* The input samples are taken from the sample_data[] array starting at
* position start_row/start_col, and moving to the right for any additional
* blocks. The quantized coefficients are returned in coef_blocks[].
*/
METHODDEF(void)
forward_DCT (j_compress_ptr cinfo, jpeg_component_info * compptr,
JSAMPARRAY sample_data, JBLOCKROW coef_blocks,
JDIMENSION start_row, JDIMENSION start_col,
JDIMENSION num_blocks)
/* This version is used for integer DCT implementations. */
{
/* This routine is heavily used, so it's worth coding it tightly. */
my_fdct_ptr fdct = (my_fdct_ptr) cinfo->fdct;
forward_DCT_method_ptr do_dct = fdct->do_dct;
DCTELEM * divisors = fdct->divisors[compptr->quant_tbl_no];
DCTELEM workspace[DCTSIZE2]; /* work area for FDCT subroutine */
JDIMENSION bi;
sample_data += start_row; /* fold in the vertical offset once */
for (bi = 0; bi < num_blocks; bi++, start_col += DCTSIZE) {
/* Load data into workspace, applying unsigned->signed conversion */
{ register DCTELEM *workspaceptr;
register JSAMPROW elemptr;
register int elemr;
workspaceptr = workspace;
for (elemr = 0; elemr < DCTSIZE; elemr++) {
elemptr = sample_data[elemr] + start_col;
#if DCTSIZE == 8 /* unroll the inner loop */
*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;
*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;
*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;
*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;
*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;
*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;
*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;
*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;
#else
{ register int elemc;
for (elemc = DCTSIZE; elemc > 0; elemc--) {
*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;
}
}
#endif
}
}
/* Perform the DCT */
(*do_dct) (workspace);
/* Quantize/descale the coefficients, and store into coef_blocks[] */
{ register DCTELEM temp, qval;
register int i;
register JCOEFPTR output_ptr = coef_blocks[bi];
for (i = 0; i < DCTSIZE2; i++) {
qval = divisors[i];
temp = workspace[i];
/* Divide the coefficient value by qval, ensuring proper rounding.
* Since C does not specify the direction of rounding for negative
* quotients, we have to force the dividend positive for portability.
*
* In most files, at least half of the output values will be zero
* (at default quantization settings, more like three-quarters...)
* so we should ensure that this case is fast. On many machines,
* a comparison is enough cheaper than a divide to make a special test
* a win. Since both inputs will be nonnegative, we need only test
* for a < b to discover whether a/b is 0.
* If your machine's division is fast enough, define FAST_DIVIDE.
*/
#ifdef FAST_DIVIDE
#define DIVIDE_BY(a,b) a /= b
#else
#define DIVIDE_BY(a,b) if (a >= b) a /= b; else a = 0
#endif
if (temp < 0) {
temp = -temp;
temp += qval>>1; /* for rounding */
DIVIDE_BY(temp, qval);
temp = -temp;
} else {
temp += qval>>1; /* for rounding */
DIVIDE_BY(temp, qval);
}
output_ptr[i] = (JCOEF) temp;
}
}
}
}
#ifdef DCT_FLOAT_SUPPORTED
METHODDEF(void)
forward_DCT_float (j_compress_ptr cinfo, jpeg_component_info * compptr,
JSAMPARRAY sample_data, JBLOCKROW coef_blocks,
JDIMENSION start_row, JDIMENSION start_col,
JDIMENSION num_blocks)
/* This version is used for floating-point DCT implementations. */
{
/* This routine is heavily used, so it's worth coding it tightly. */
my_fdct_ptr fdct = (my_fdct_ptr) cinfo->fdct;
float_DCT_method_ptr do_dct = fdct->do_float_dct;
FAST_FLOAT * divisors = fdct->float_divisors[compptr->quant_tbl_no];
FAST_FLOAT workspace[DCTSIZE2]; /* work area for FDCT subroutine */
JDIMENSION bi;
sample_data += start_row; /* fold in the vertical offset once */
for (bi = 0; bi < num_blocks; bi++, start_col += DCTSIZE) {
/* Load data into workspace, applying unsigned->signed conversion */
{ register FAST_FLOAT *workspaceptr;
register JSAMPROW elemptr;
register int elemr;
workspaceptr = workspace;
for (elemr = 0; elemr < DCTSIZE; elemr++) {
elemptr = sample_data[elemr] + start_col;
#if DCTSIZE == 8 /* unroll the inner loop */
*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);
*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);
*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);
*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);
*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);
*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);
*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);
*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);
#else
{ register int elemc;
for (elemc = DCTSIZE; elemc > 0; elemc--) {
*workspaceptr++ = (FAST_FLOAT)
(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);
}
}
#endif
}
}
/* Perform the DCT */
(*do_dct) (workspace);
/* Quantize/descale the coefficients, and store into coef_blocks[] */
{ register FAST_FLOAT temp;
register int i;
register JCOEFPTR output_ptr = coef_blocks[bi];
for (i = 0; i < DCTSIZE2; i++) {
/* Apply the quantization and scaling factor */
temp = workspace[i] * divisors[i];
/* Round to nearest integer.
* Since C does not specify the direction of rounding for negative
* quotients, we have to force the dividend positive for portability.
* The maximum coefficient size is +-16K (for 12-bit data), so this
* code should work for either 16-bit or 32-bit ints.
*/
output_ptr[i] = (JCOEF) ((int) (temp + (FAST_FLOAT) 16384.5) - 16384);
}
}
}
}
#endif /* DCT_FLOAT_SUPPORTED */
/*
* Initialize FDCT manager.
*/
GLOBAL(void)
jinit_forward_dct (j_compress_ptr cinfo)
{
my_fdct_ptr fdct;
int i;
fdct = (my_fdct_ptr)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
SIZEOF(my_fdct_controller));
cinfo->fdct = (struct jpeg_forward_dct *) fdct;
fdct->pub.start_pass = start_pass_fdctmgr;
switch (cinfo->dct_method) {
#ifdef DCT_ISLOW_SUPPORTED
case JDCT_ISLOW:
fdct->pub.forward_DCT = forward_DCT;
fdct->do_dct = jpeg_fdct_islow;
break;
#endif
#ifdef DCT_IFAST_SUPPORTED
case JDCT_IFAST:
fdct->pub.forward_DCT = forward_DCT;
fdct->do_dct = jpeg_fdct_ifast;
break;
#endif
#ifdef DCT_FLOAT_SUPPORTED
case JDCT_FLOAT:
fdct->pub.forward_DCT = forward_DCT_float;
fdct->do_float_dct = jpeg_fdct_float;
break;
#endif
default:
ERREXIT(cinfo, JERR_NOT_COMPILED);
break;
}
/* Mark divisor tables unallocated */
for (i = 0; i < NUM_QUANT_TBLS; i++) {
fdct->divisors[i] = NULL;
#ifdef DCT_FLOAT_SUPPORTED
fdct->float_divisors[i] = NULL;
#endif
}
}
dlib/external/libjpeg/jchuff.cpp 0 → 100644
View file @ 747088ea
/*
* jchuff.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 encoding routines.
*
* Much of the complexity here has to do with supporting output suspension.
* If the data destination 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 JPEG objects only upon successful completion of an MCU.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
#include "jchuff.h" /* Declarations shared with jcphuff.c */
/* Expanded entropy encoder object for Huffman encoding.
*
* The savable_state subrecord contains fields that change within an MCU,
* but must not be updated permanently until we complete the MCU.
*/
typedef struct {
long put_buffer; /* current bit-accumulation buffer */
int put_bits; /* # of bits now in it */
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).put_buffer = (src).put_buffer, \
(dest).put_bits = (src).put_bits, \
(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_encoder pub; /* public fields */
savable_state saved; /* Bit buffer & DC 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 */
int next_restart_num; /* next restart number to write (0-7) */
/* Pointers to derived tables (these workspaces have image lifespan) */
c_derived_tbl * dc_derived_tbls[NUM_HUFF_TBLS];
c_derived_tbl * ac_derived_tbls[NUM_HUFF_TBLS];
#ifdef ENTROPY_OPT_SUPPORTED /* Statistics tables for optimization */
long * dc_count_ptrs[NUM_HUFF_TBLS];
long * ac_count_ptrs[NUM_HUFF_TBLS];
#endif
} huff_entropy_encoder;
typedef huff_entropy_encoder * huff_entropy_ptr;
/* Working state while writing an MCU.
* This struct contains all the fields that are needed by subroutines.
*/
typedef struct {
JOCTET * next_output_byte; /* => next byte to write in buffer */
size_t free_in_buffer; /* # of byte spaces remaining in buffer */
savable_state cur; /* Current bit buffer & DC state */
j_compress_ptr cinfo; /* dump_buffer needs access to this */
} working_state;
/* Forward declarations */
METHODDEF(int) encode_mcu_huff JPP((j_compress_ptr cinfo,
JBLOCKROW *MCU_data));
METHODDEF(void) finish_pass_huff JPP((j_compress_ptr cinfo));
#ifdef ENTROPY_OPT_SUPPORTED
METHODDEF(int) encode_mcu_gather JPP((j_compress_ptr cinfo,
JBLOCKROW *MCU_data));
METHODDEF(void) finish_pass_gather JPP((j_compress_ptr cinfo));
#endif
/*
* Initialize for a Huffman-compressed scan.
* If gather_statistics is TRUE, we do not output anything during the scan,
* just count the Huffman symbols used and generate Huffman code tables.
*/
METHODDEF(void)
start_pass_huff (j_compress_ptr cinfo, int gather_statistics)
{
huff_entropy_ptr entropy = (huff_entropy_ptr) cinfo->entropy;
int ci, dctbl, actbl;
jpeg_component_info * compptr;
if (gather_statistics) {
#ifdef ENTROPY_OPT_SUPPORTED
entropy->pub.encode_mcu = encode_mcu_gather;
entropy->pub.finish_pass = finish_pass_gather;
#else
ERREXIT(cinfo, JERR_NOT_COMPILED);
#endif
} else {
entropy->pub.encode_mcu = encode_mcu_huff;
entropy->pub.finish_pass = finish_pass_huff;
}
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;
if (gather_statistics) {
#ifdef ENTROPY_OPT_SUPPORTED
/* Check for invalid table indexes */
/* (make_c_derived_tbl does this in the other path) */
if (dctbl < 0 || dctbl >= NUM_HUFF_TBLS)
ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, dctbl);
if (actbl < 0 || actbl >= NUM_HUFF_TBLS)
ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, actbl);
/* Allocate and zero the statistics tables */
/* Note that jpeg_gen_optimal_table expects 257 entries in each table! */
if (entropy->dc_count_ptrs[dctbl] == NULL)
entropy->dc_count_ptrs[dctbl] = (long *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
257 * SIZEOF(long));
MEMZERO(entropy->dc_count_ptrs[dctbl], 257 * SIZEOF(long));
if (entropy->ac_count_ptrs[actbl] == NULL)
entropy->ac_count_ptrs[actbl] = (long *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
257 * SIZEOF(long));
MEMZERO(entropy->ac_count_ptrs[actbl], 257 * SIZEOF(long));
#endif
} else {
/* Compute derived values for Huffman tables */
/* We may do this more than once for a table, but it's not expensive */
jpeg_make_c_derived_tbl(cinfo, TRUE, dctbl,
& entropy->dc_derived_tbls[dctbl]);
jpeg_make_c_derived_tbl(cinfo, FALSE, actbl,
& entropy->ac_derived_tbls[actbl]);
}
/* Initialize DC predictions to 0 */
entropy->saved.last_dc_val[ci] = 0;
}
/* Initialize bit buffer to empty */
entropy->saved.put_buffer = 0;
entropy->saved.put_bits = 0;
/* Initialize restart stuff */
entropy->restarts_to_go = cinfo->restart_interval;
entropy->next_restart_num = 0;
}
/*
* Compute the derived values for a Huffman table.
* This routine also performs some validation checks on the table.
*
* Note this is also used by jcphuff.c.
*/
GLOBAL(void)
jpeg_make_c_derived_tbl (j_compress_ptr cinfo, int isDC, int tblno,
c_derived_tbl ** pdtbl)
{
JHUFF_TBL *htbl;
c_derived_tbl *dtbl;
int p, i, l, lastp, si, maxsymbol;
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 = (c_derived_tbl *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
SIZEOF(c_derived_tbl));
dtbl = *pdtbl;
/* 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;
lastp = 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 (((long) code) >= (((long) 1) << si))
ERREXIT(cinfo, JERR_BAD_HUFF_TABLE);
code <<= 1;
si++;
}
/* Figure C.3: generate encoding tables */
/* These are code and size indexed by symbol value */
/* Set all codeless symbols to have code length 0;
* this lets us detect duplicate VAL entries here, and later
* allows emit_bits to detect any attempt to emit such symbols.
*/
MEMZERO(dtbl->ehufsi, SIZEOF(dtbl->ehufsi));
/* This is also a convenient place to check for out-of-range
* and duplicated VAL entries. We allow 0..255 for AC symbols
* but only 0..15 for DC. (We could constrain them further
* based on data depth and mode, but this seems enough.)
*/
maxsymbol = isDC ? 15 : 255;
for (p = 0; p < lastp; p++) {
i = htbl->huffval[p];
if (i < 0 || i > maxsymbol || dtbl->ehufsi[i])
ERREXIT(cinfo, JERR_BAD_HUFF_TABLE);
dtbl->ehufco[i] = huffcode[p];
dtbl->ehufsi[i] = huffsize[p];
}
}
/* Outputting bytes to the file */
/* Emit a byte, taking 'action' if must suspend. */
#define emit_byte(state,val,action) \
{ *(state)->next_output_byte++ = (JOCTET) (val); \
if (--(state)->free_in_buffer == 0) \
if (! dump_buffer(state)) \
{ action; } }
LOCAL(int)
dump_buffer (working_state * state)
/* Empty the output buffer; return TRUE if successful, FALSE if must suspend */
{
struct jpeg_destination_mgr * dest = state->cinfo->dest;
if (! (*dest->empty_output_buffer) (state->cinfo))
return FALSE;
/* After a successful buffer dump, must reset buffer pointers */
state->next_output_byte = dest->next_output_byte;
state->free_in_buffer = dest->free_in_buffer;
return TRUE;
}
/* Outputting bits to the file */
/* Only the right 24 bits of put_buffer are used; the valid bits are
* left-justified in this part. At most 16 bits can be passed to emit_bits
* in one call, and we never retain more than 7 bits in put_buffer
* between calls, so 24 bits are sufficient.
*/
INLINE
LOCAL(int)
emit_bits (working_state * state, unsigned int code, int size)
/* Emit some bits; return TRUE if successful, FALSE if must suspend */
{
/* This routine is heavily used, so it's worth coding tightly. */
register long put_buffer = (long) code;
register int put_bits = state->cur.put_bits;
/* if size is 0, caller used an invalid Huffman table entry */
if (size == 0)
ERREXIT(state->cinfo, JERR_HUFF_MISSING_CODE);
put_buffer &= (((long) 1)<<size) - 1; /* mask off any extra bits in code */
put_bits += size; /* new number of bits in buffer */
put_buffer <<= 24 - put_bits; /* align incoming bits */
put_buffer |= state->cur.put_buffer; /* and merge with old buffer contents */
while (put_bits >= 8) {
int c = (int) ((put_buffer >> 16) & 0xFF);
emit_byte(state, c, return FALSE);
if (c == 0xFF) { /* need to stuff a zero byte? */
emit_byte(state, 0, return FALSE);
}
put_buffer <<= 8;
put_bits -= 8;
}
state->cur.put_buffer = put_buffer; /* update state variables */
state->cur.put_bits = put_bits;
return TRUE;
}
LOCAL(int)
flush_bits (working_state * state)
{
if (! emit_bits(state, 0x7F, 7)) /* fill any partial byte with ones */
return FALSE;
state->cur.put_buffer = 0; /* and reset bit-buffer to empty */
state->cur.put_bits = 0;
return TRUE;
}
/* Encode a single block's worth of coefficients */
LOCAL(int)
encode_one_block (working_state * state, JCOEFPTR block, int last_dc_val,
c_derived_tbl *dctbl, c_derived_tbl *actbl)
{
register int temp, temp2;
register int nbits;
register int k, r, i;
/* Encode the DC coefficient difference per section F.1.2.1 */
temp = temp2 = block[0] - last_dc_val;
if (temp < 0) {
temp = -temp; /* temp is abs value of input */
/* For a negative input, want temp2 = bitwise complement of abs(input) */
/* This code assumes we are on a two's complement machine */
temp2--;
}
/* Find the number of bits needed for the magnitude of the coefficient */
nbits = 0;
while (temp) {
nbits++;
temp >>= 1;
}
/* Check for out-of-range coefficient values.
* Since we're encoding a difference, the range limit is twice as much.
*/
if (nbits > MAX_COEF_BITS+1)
ERREXIT(state->cinfo, JERR_BAD_DCT_COEF);
/* Emit the Huffman-coded symbol for the number of bits */
if (! emit_bits(state, dctbl->ehufco[nbits], dctbl->ehufsi[nbits]))
return FALSE;
/* Emit that number of bits of the value, if positive, */
/* or the complement of its magnitude, if negative. */
if (nbits) /* emit_bits rejects calls with size 0 */
if (! emit_bits(state, (unsigned int) temp2, nbits))
return FALSE;
/* Encode the AC coefficients per section F.1.2.2 */
r = 0; /* r = run length of zeros */
for (k = 1; k < DCTSIZE2; k++) {
if ((temp = block[jpeg_natural_order[k]]) == 0) {
r++;
} else {
/* if run length > 15, must emit special run-length-16 codes (0xF0) */
while (r > 15) {
if (! emit_bits(state, actbl->ehufco[0xF0], actbl->ehufsi[0xF0]))
return FALSE;
r -= 16;
}
temp2 = temp;
if (temp < 0) {
temp = -temp; /* temp is abs value of input */
/* This code assumes we are on a two's complement machine */
temp2--;
}
/* Find the number of bits needed for the magnitude of the coefficient */
nbits = 1; /* there must be at least one 1 bit */
while ((temp >>= 1))
nbits++;
/* Check for out-of-range coefficient values */
if (nbits > MAX_COEF_BITS)
ERREXIT(state->cinfo, JERR_BAD_DCT_COEF);
/* Emit Huffman symbol for run length / number of bits */
i = (r << 4) + nbits;
if (! emit_bits(state, actbl->ehufco[i], actbl->ehufsi[i]))
return FALSE;
/* Emit that number of bits of the value, if positive, */
/* or the complement of its magnitude, if negative. */
if (! emit_bits(state, (unsigned int) temp2, nbits))
return FALSE;
r = 0;
}
}
/* If the last coef(s) were zero, emit an end-of-block code */
if (r > 0)
if (! emit_bits(state, actbl->ehufco[0], actbl->ehufsi[0]))
return FALSE;
return TRUE;
}
/*
* Emit a restart marker & resynchronize predictions.
*/
LOCAL(int)
emit_restart (working_state * state, int restart_num)
{
int ci;
if (! flush_bits(state))
return FALSE;
emit_byte(state, 0xFF, return FALSE);
emit_byte(state, JPEG_RST0 + restart_num, return FALSE);
/* Re-initialize DC predictions to 0 */
for (ci = 0; ci < state->cinfo->comps_in_scan; ci++)
state->cur.last_dc_val[ci] = 0;
/* The restart counter is not updated until we successfully write the MCU. */
return TRUE;
}
/*
* Encode and output one MCU's worth of Huffman-compressed coefficients.
*/
METHODDEF(int)
encode_mcu_huff (j_compress_ptr cinfo, JBLOCKROW *MCU_data)
{
huff_entropy_ptr entropy = (huff_entropy_ptr) cinfo->entropy;
working_state state;
int blkn, ci;
jpeg_component_info * compptr;
/* Load up working state */
state.next_output_byte = cinfo->dest->next_output_byte;
state.free_in_buffer = cinfo->dest->free_in_buffer;
ASSIGN_STATE(state.cur, entropy->saved);
state.cinfo = cinfo;
/* Emit restart marker if needed */
if (cinfo->restart_interval) {
if (entropy->restarts_to_go == 0)
if (! emit_restart(&state, entropy->next_restart_num))
return FALSE;
}
/* Encode the MCU data blocks */
for (blkn = 0; blkn < cinfo->blocks_in_MCU; blkn++) {
ci = cinfo->MCU_membership[blkn];
compptr = cinfo->cur_comp_info[ci];
if (! encode_one_block(&state,
MCU_data[blkn][0], state.cur.last_dc_val[ci],
entropy->dc_derived_tbls[compptr->dc_tbl_no],
entropy->ac_derived_tbls[compptr->ac_tbl_no]))
return FALSE;
/* Update last_dc_val */
state.cur.last_dc_val[ci] = MCU_data[blkn][0][0];
}
/* Completed MCU, so update state */
cinfo->dest->next_output_byte = state.next_output_byte;
cinfo->dest->free_in_buffer = state.free_in_buffer;
ASSIGN_STATE(entropy->saved, state.cur);
/* Update restart-interval state too */
if (cinfo->restart_interval) {
if (entropy->restarts_to_go == 0) {
entropy->restarts_to_go = cinfo->restart_interval;
entropy->next_restart_num++;
entropy->next_restart_num &= 7;
}
entropy->restarts_to_go--;
}
return TRUE;
}
/*
* Finish up at the end of a Huffman-compressed scan.
*/
METHODDEF(void)
finish_pass_huff (j_compress_ptr cinfo)
{
huff_entropy_ptr entropy = (huff_entropy_ptr) cinfo->entropy;
working_state state;
/* Load up working state ... flush_bits needs it */
state.next_output_byte = cinfo->dest->next_output_byte;
state.free_in_buffer = cinfo->dest->free_in_buffer;
ASSIGN_STATE(state.cur, entropy->saved);
state.cinfo = cinfo;
/* Flush out the last data */
if (! flush_bits(&state))
ERREXIT(cinfo, JERR_CANT_SUSPEND);
/* Update state */
cinfo->dest->next_output_byte = state.next_output_byte;
cinfo->dest->free_in_buffer = state.free_in_buffer;
ASSIGN_STATE(entropy->saved, state.cur);
}
/*
* Huffman coding optimization.
*
* We first scan the supplied data and count the number of uses of each symbol
* that is to be Huffman-coded. (This process MUST agree with the code above.)
* Then we build a Huffman coding tree for the observed counts.
* Symbols which are not needed at all for the particular image are not
* assigned any code, which saves space in the DHT marker as well as in
* the compressed data.
*/
#ifdef ENTROPY_OPT_SUPPORTED
/* Process a single block's worth of coefficients */
LOCAL(void)
htest_one_block (j_compress_ptr cinfo, JCOEFPTR block, int last_dc_val,
long dc_counts[], long ac_counts[])
{
register int temp;
register int nbits;
register int k, r;
/* Encode the DC coefficient difference per section F.1.2.1 */
temp = block[0] - last_dc_val;
if (temp < 0)
temp = -temp;
/* Find the number of bits needed for the magnitude of the coefficient */
nbits = 0;
while (temp) {
nbits++;
temp >>= 1;
}
/* Check for out-of-range coefficient values.
* Since we're encoding a difference, the range limit is twice as much.
*/
if (nbits > MAX_COEF_BITS+1)
ERREXIT(cinfo, JERR_BAD_DCT_COEF);
/* Count the Huffman symbol for the number of bits */
dc_counts[nbits]++;
/* Encode the AC coefficients per section F.1.2.2 */
r = 0; /* r = run length of zeros */
for (k = 1; k < DCTSIZE2; k++) {
if ((temp = block[jpeg_natural_order[k]]) == 0) {
r++;
} else {
/* if run length > 15, must emit special run-length-16 codes (0xF0) */
while (r > 15) {
ac_counts[0xF0]++;
r -= 16;
}
/* Find the number of bits needed for the magnitude of the coefficient */
if (temp < 0)
temp = -temp;
/* Find the number of bits needed for the magnitude of the coefficient */
nbits = 1; /* there must be at least one 1 bit */
while ((temp >>= 1))
nbits++;
/* Check for out-of-range coefficient values */
if (nbits > MAX_COEF_BITS)
ERREXIT(cinfo, JERR_BAD_DCT_COEF);
/* Count Huffman symbol for run length / number of bits */
ac_counts[(r << 4) + nbits]++;
r = 0;
}
}
/* If the last coef(s) were zero, emit an end-of-block code */
if (r > 0)
ac_counts[0]++;
}
/*
* Trial-encode one MCU's worth of Huffman-compressed coefficients.
* No data is actually output, so no suspension return is possible.
*/
METHODDEF(int)
encode_mcu_gather (j_compress_ptr cinfo, JBLOCKROW *MCU_data)
{
huff_entropy_ptr entropy = (huff_entropy_ptr) cinfo->entropy;
int blkn, ci;
jpeg_component_info * compptr;
/* Take care of restart intervals if needed */
if (cinfo->restart_interval) {
if (entropy->restarts_to_go == 0) {
/* Re-initialize DC predictions to 0 */
for (ci = 0; ci < cinfo->comps_in_scan; ci++)
entropy->saved.last_dc_val[ci] = 0;
/* Update restart state */
entropy->restarts_to_go = cinfo->restart_interval;
}
entropy->restarts_to_go--;
}
for (blkn = 0; blkn < cinfo->blocks_in_MCU; blkn++) {
ci = cinfo->MCU_membership[blkn];
compptr = cinfo->cur_comp_info[ci];
htest_one_block(cinfo, MCU_data[blkn][0], entropy->saved.last_dc_val[ci],
entropy->dc_count_ptrs[compptr->dc_tbl_no],
entropy->ac_count_ptrs[compptr->ac_tbl_no]);
entropy->saved.last_dc_val[ci] = MCU_data[blkn][0][0];
}
return TRUE;
}
/*
* Generate the best Huffman code table for the given counts, fill htbl.
* Note this is also used by jcphuff.c.
*
* The JPEG standard requires that no symbol be assigned a codeword of all
* one bits (so that padding bits added at the end of a compressed segment
* can't look like a valid code). Because of the canonical ordering of
* codewords, this just means that there must be an unused slot in the
* longest codeword length category. Section K.2 of the JPEG spec suggests
* reserving such a slot by pretending that symbol 256 is a valid symbol
* with count 1. In theory that's not optimal; giving it count zero but
* including it in the symbol set anyway should give a better Huffman code.
* But the theoretically better code actually seems to come out worse in
* practice, because it produces more all-ones bytes (which incur stuffed
* zero bytes in the final file). In any case the difference is tiny.
*
* The JPEG standard requires Huffman codes to be no more than 16 bits long.
* If some symbols have a very small but nonzero probability, the Huffman tree
* must be adjusted to meet the code length restriction. We currently use
* the adjustment method suggested in JPEG section K.2. This method is *not*
* optimal; it may not choose the best possible limited-length code. But
* typically only very-low-frequency symbols will be given less-than-optimal
* lengths, so the code is almost optimal. Experimental comparisons against
* an optimal limited-length-code algorithm indicate that the difference is
* microscopic --- usually less than a hundredth of a percent of total size.
* So the extra complexity of an optimal algorithm doesn't seem worthwhile.
*/
GLOBAL(void)
jpeg_gen_optimal_table (j_compress_ptr cinfo, JHUFF_TBL * htbl, long freq[])
{
#define MAX_CLEN 32 /* assumed maximum initial code length */
unsigned short bits[MAX_CLEN+1]; /* bits[k] = # of symbols with code length k */
int codesize[257]; /* codesize[k] = code length of symbol k */
int others[257]; /* next symbol in current branch of tree */
int c1, c2;
int p, i, j;
long v;
/* This algorithm is explained in section K.2 of the JPEG standard */
MEMZERO(bits, SIZEOF(bits));
MEMZERO(codesize, SIZEOF(codesize));
for (i = 0; i < 257; i++)
others[i] = -1; /* init links to empty */
freq[256] = 1; /* make sure 256 has a nonzero count */
/* Including the pseudo-symbol 256 in the Huffman procedure guarantees
* that no real symbol is given code-value of all ones, because 256
* will be placed last in the largest codeword category.
*/
/* Huffman's basic algorithm to assign optimal code lengths to symbols */
for (;;) {
/* Find the smallest nonzero frequency, set c1 = its symbol */
/* In case of ties, take the larger symbol number */
c1 = -1;
v = 1000000000L;
for (i = 0; i <= 256; i++) {
if (freq[i] && freq[i] <= v) {
v = freq[i];
c1 = i;
}
}
/* Find the next smallest nonzero frequency, set c2 = its symbol */
/* In case of ties, take the larger symbol number */
c2 = -1;
v = 1000000000L;
for (i = 0; i <= 256; i++) {
if (freq[i] && freq[i] <= v && i != c1) {
v = freq[i];
c2 = i;
}
}
/* Done if we've merged everything into one frequency */
if (c2 < 0)
break;
/* Else merge the two counts/trees */
freq[c1] += freq[c2];
freq[c2] = 0;
/* Increment the codesize of everything in c1's tree branch */
codesize[c1]++;
while (others[c1] >= 0) {
c1 = others[c1];
codesize[c1]++;
}
others[c1] = c2; /* chain c2 onto c1's tree branch */
/* Increment the codesize of everything in c2's tree branch */
codesize[c2]++;
while (others[c2] >= 0) {
c2 = others[c2];
codesize[c2]++;
}
}
/* Now count the number of symbols of each code length */
for (i = 0; i <= 256; i++) {
if (codesize[i]) {
/* The JPEG standard seems to think that this can't happen, */
/* but I'm paranoid... */
if (codesize[i] > MAX_CLEN)
ERREXIT(cinfo, JERR_HUFF_CLEN_OVERFLOW);
bits[codesize[i]]++;
}
}
/* JPEG doesn't allow symbols with code lengths over 16 bits, so if the pure
* Huffman procedure assigned any such lengths, we must adjust the coding.
* Here is what the JPEG spec says about how this next bit works:
* Since symbols are paired for the longest Huffman code, the symbols are
* removed from this length category two at a time. The prefix for the pair
* (which is one bit shorter) is allocated to one of the pair; then,
* skipping the BITS entry for that prefix length, a code word from the next
* shortest nonzero BITS entry is converted into a prefix for two code words
* one bit longer.
*/
for (i = MAX_CLEN; i > 16; i--) {
while (bits[i] > 0) {
j = i - 2; /* find length of new prefix to be used */
while (bits[j] == 0)
j--;
bits[i] -= 2; /* remove two symbols */
bits[i-1]++; /* one goes in this length */
bits[j+1] += 2; /* two new symbols in this length */
bits[j]--; /* symbol of this length is now a prefix */
}
}
/* Remove the count for the pseudo-symbol 256 from the largest codelength */
while (bits[i] == 0) /* find largest codelength still in use */
i--;
bits[i]--;
/* Return final symbol counts (only for lengths 0..16) */
MEMCOPY(htbl->bits, bits, SIZEOF(htbl->bits));
/* Return a list of the symbols sorted by code length */
/* It's not real clear to me why we don't need to consider the codelength
* changes made above, but the JPEG spec seems to think this works.
*/
p = 0;
for (i = 1; i <= MAX_CLEN; i++) {
for (j = 0; j <= 255; j++) {
if (codesize[j] == i) {
htbl->huffval[p] = (unsigned short) j;
p++;
}
}
}
/* Set sent_table FALSE so updated table will be written to JPEG file. */
htbl->sent_table = FALSE;
}
/*
* Finish up a statistics-gathering pass and create the new Huffman tables.
*/
METHODDEF(void)
finish_pass_gather (j_compress_ptr cinfo)
{
huff_entropy_ptr entropy = (huff_entropy_ptr) cinfo->entropy;
int ci, dctbl, actbl;
jpeg_component_info * compptr;
JHUFF_TBL **htblptr;
int did_dc[NUM_HUFF_TBLS];
int did_ac[NUM_HUFF_TBLS];
/* It's important not to apply jpeg_gen_optimal_table more than once
* per table, because it clobbers the input frequency counts!
*/
MEMZERO(did_dc, SIZEOF(did_dc));
MEMZERO(did_ac, SIZEOF(did_ac));
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;
if (! did_dc[dctbl]) {
htblptr = & cinfo->dc_huff_tbl_ptrs[dctbl];
if (*htblptr == NULL)
*htblptr = jpeg_alloc_huff_table((j_common_ptr) cinfo);
jpeg_gen_optimal_table(cinfo, *htblptr, entropy->dc_count_ptrs[dctbl]);
did_dc[dctbl] = TRUE;
}
if (! did_ac[actbl]) {
htblptr = & cinfo->ac_huff_tbl_ptrs[actbl];
if (*htblptr == NULL)
*htblptr = jpeg_alloc_huff_table((j_common_ptr) cinfo);
jpeg_gen_optimal_table(cinfo, *htblptr, entropy->ac_count_ptrs[actbl]);
did_ac[actbl] = TRUE;
}
}
}
#endif /* ENTROPY_OPT_SUPPORTED */
/*
* Module initialization routine for Huffman entropy encoding.
*/
GLOBAL(void)
jinit_huff_encoder (j_compress_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_encoder));
cinfo->entropy = (struct jpeg_entropy_encoder *) entropy;
entropy->pub.start_pass = start_pass_huff;
/* Mark tables unallocated */
for (i = 0; i < NUM_HUFF_TBLS; i++) {
entropy->dc_derived_tbls[i] = entropy->ac_derived_tbls[i] = NULL;
#ifdef ENTROPY_OPT_SUPPORTED
entropy->dc_count_ptrs[i] = entropy->ac_count_ptrs[i] = NULL;
#endif
}
}
dlib/external/libjpeg/jchuff.h 0 → 100644
View file @ 747088ea
/*
* jchuff.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 encoding routines
* that are shared between the sequential encoder (jchuff.c) and the
* progressive encoder (jcphuff.c). No other modules need to see these.
*/
/* The legal range of a DCT coefficient is
* -1024 .. +1023 for 8-bit data;
* -16384 .. +16383 for 12-bit data.
* Hence the magnitude should always fit in 10 or 14 bits respectively.
*/
#if BITS_IN_JSAMPLE == 8
#define MAX_COEF_BITS 10
#else
#define MAX_COEF_BITS 14
#endif
/* Derived data constructed for each Huffman table */
typedef struct {
unsigned int ehufco[256]; /* code for each symbol */
char ehufsi[256]; /* length of code for each symbol */
/* If no code has been allocated for a symbol S, ehufsi[S] contains 0 */
} c_derived_tbl;
/* Short forms of external names for systems with brain-damaged linkers. */
#ifdef NEED_SHORT_EXTERNAL_NAMES
#define jpeg_make_c_derived_tbl jMkCDerived
#define jpeg_gen_optimal_table jGenOptTbl
#endif /* NEED_SHORT_EXTERNAL_NAMES */
/* Expand a Huffman table definition into the derived format */
EXTERN(void) jpeg_make_c_derived_tbl
JPP((j_compress_ptr cinfo, int isDC, int tblno,
c_derived_tbl ** pdtbl));
/* Generate an optimal table definition given the specified counts */
EXTERN(void) jpeg_gen_optimal_table
JPP((j_compress_ptr cinfo, JHUFF_TBL * htbl, long freq[]));
dlib/external/libjpeg/jcinit.cpp 0 → 100644
View file @ 747088ea
/*
* jcinit.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 initialization logic for the JPEG compressor.
* This routine is in charge of selecting the modules to be executed and
* making an initialization call to each one.
*
* Logically, this code belongs in jcmaster.c. It's split out because
* linking this routine implies linking the entire compression library.
* For a transcoding-only application, we want to be able to use jcmaster.c
* without linking in the whole library.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
/*
* Master selection of compression modules.
* This is done once at the start of processing an image. We determine
* which modules will be used and give them appropriate initialization calls.
*/
GLOBAL(void)
jinit_compress_master (j_compress_ptr cinfo)
{
/* Initialize master control (includes parameter checking/processing) */
jinit_c_master_control(cinfo, FALSE /* full compression */);
/* Preprocessing */
if (! cinfo->raw_data_in) {
jinit_color_converter(cinfo);
jinit_downsampler(cinfo);
jinit_c_prep_controller(cinfo, FALSE /* never need full buffer here */);
}
/* Forward DCT */
jinit_forward_dct(cinfo);
/* Entropy encoding: either Huffman or arithmetic coding. */
if (cinfo->arith_code) {
ERREXIT(cinfo, JERR_ARITH_NOTIMPL);
} else {
if (cinfo->progressive_mode) {
#ifdef C_PROGRESSIVE_SUPPORTED
jinit_phuff_encoder(cinfo);
#else
ERREXIT(cinfo, JERR_NOT_COMPILED);
#endif
} else
jinit_huff_encoder(cinfo);
}
/* Need a full-image coefficient buffer in any multi-pass mode. */
jinit_c_coef_controller(cinfo,
(int) (cinfo->num_scans > 1 || cinfo->optimize_coding));
jinit_c_main_controller(cinfo, FALSE /* never need full buffer here */);
jinit_marker_writer(cinfo);
/* We can now tell the memory manager to allocate virtual arrays. */
(*cinfo->mem->realize_virt_arrays) ((j_common_ptr) cinfo);
/* Write the datastream header (SOI) immediately.
* Frame and scan headers are postponed till later.
* This lets application insert special markers after the SOI.
*/
(*cinfo->marker->write_file_header) (cinfo);
}
dlib/external/libjpeg/jcmainct.cpp 0 → 100644
View file @ 747088ea
/*
* jcmainct.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 compression.
* The main buffer lies between the pre-processor and the JPEG
* compressor proper; it holds downsampled data in the JPEG colorspace.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
/* Note: currently, there is no operating mode in which a full-image buffer
* is needed at this step. If there were, that mode could not be used with
* "raw data" input, since this module is bypassed in that case. However,
* we've left the code here for possible use in special applications.
*/
#undef FULL_MAIN_BUFFER_SUPPORTED
/* Private buffer controller object */
typedef struct {
struct jpeg_c_main_controller pub; /* public fields */
JDIMENSION cur_iMCU_row; /* number of current iMCU row */
JDIMENSION rowgroup_ctr; /* counts row groups received in iMCU row */
int suspended; /* remember if we suspended output */
J_BUF_MODE pass_mode; /* current operating mode */
/* If using just a strip buffer, this points to the entire set of buffers
* (we allocate one for each component). In the full-image case, this
* points to the currently accessible strips of the virtual arrays.
*/
JSAMPARRAY buffer[MAX_COMPONENTS];
#ifdef FULL_MAIN_BUFFER_SUPPORTED
/* If using full-image storage, this array holds pointers to virtual-array
* control blocks for each component. Unused if not full-image storage.
*/
jvirt_sarray_ptr whole_image[MAX_COMPONENTS];
#endif
} my_main_controller;
typedef my_main_controller * my_main_ptr;
/* Forward declarations */
METHODDEF(void) process_data_simple_main
JPP((j_compress_ptr cinfo, JSAMPARRAY input_buf,
JDIMENSION *in_row_ctr, JDIMENSION in_rows_avail));
#ifdef FULL_MAIN_BUFFER_SUPPORTED
METHODDEF(void) process_data_buffer_main
JPP((j_compress_ptr cinfo, JSAMPARRAY input_buf,
JDIMENSION *in_row_ctr, JDIMENSION in_rows_avail));
#endif
/*
* Initialize for a processing pass.
*/
METHODDEF(void)
start_pass_main (j_compress_ptr cinfo, J_BUF_MODE pass_mode)
{
my_main_ptr main = (my_main_ptr) cinfo->main;
/* Do nothing in raw-data mode. */
if (cinfo->raw_data_in)
return;
main->cur_iMCU_row = 0; /* initialize counters */
main->rowgroup_ctr = 0;
main->suspended = FALSE;
main->pass_mode = pass_mode; /* save mode for use by process_data */
switch (pass_mode) {
case JBUF_PASS_THRU:
#ifdef FULL_MAIN_BUFFER_SUPPORTED
if (main->whole_image[0] != NULL)
ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
#endif
main->pub.process_data = process_data_simple_main;
break;
#ifdef FULL_MAIN_BUFFER_SUPPORTED
case JBUF_SAVE_SOURCE:
case JBUF_CRANK_DEST:
case JBUF_SAVE_AND_PASS:
if (main->whole_image[0] == NULL)
ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
main->pub.process_data = process_data_buffer_main;
break;
#endif
default:
ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
break;
}
}
/*
* Process some data.
* This routine handles the simple pass-through mode,
* where we have only a strip buffer.
*/
METHODDEF(void)
process_data_simple_main (j_compress_ptr cinfo,
JSAMPARRAY input_buf, JDIMENSION *in_row_ctr,
JDIMENSION in_rows_avail)
{
my_main_ptr main = (my_main_ptr) cinfo->main;
while (main->cur_iMCU_row < cinfo->total_iMCU_rows) {
/* Read input data if we haven't filled the main buffer yet */
if (main->rowgroup_ctr < DCTSIZE)
(*cinfo->prep->pre_process_data) (cinfo,
input_buf, in_row_ctr, in_rows_avail,
main->buffer, &main->rowgroup_ctr,
(JDIMENSION) DCTSIZE);
/* If we don't have a full iMCU row buffered, return to application for
* more data. Note that preprocessor will always pad to fill the iMCU row
* at the bottom of the image.
*/
if (main->rowgroup_ctr != DCTSIZE)
return;
/* Send the completed row to the compressor */
if (! (*cinfo->coef->compress_data) (cinfo, main->buffer)) {
/* If compressor did not consume the whole row, then we must need to
* suspend processing and return to the application. In this situation
* we pretend we didn't yet consume the last input row; otherwise, if
* it happened to be the last row of the image, the application would
* think we were done.
*/
if (! main->suspended) {
(*in_row_ctr)--;
main->suspended = TRUE;
}
return;
}
/* We did finish the row. Undo our little suspension hack if a previous
* call suspended; then mark the main buffer empty.
*/
if (main->suspended) {
(*in_row_ctr)++;
main->suspended = FALSE;
}
main->rowgroup_ctr = 0;
main->cur_iMCU_row++;
}
}
#ifdef FULL_MAIN_BUFFER_SUPPORTED
/*
* Process some data.
* This routine handles all of the modes that use a full-size buffer.
*/
METHODDEF(void)
process_data_buffer_main (j_compress_ptr cinfo,
JSAMPARRAY input_buf, JDIMENSION *in_row_ctr,
JDIMENSION in_rows_avail)
{
my_main_ptr main = (my_main_ptr) cinfo->main;
int ci;
jpeg_component_info *compptr;
int writing = (main->pass_mode != JBUF_CRANK_DEST);
while (main->cur_iMCU_row < cinfo->total_iMCU_rows) {
/* Realign the virtual buffers if at the start of an iMCU row. */
if (main->rowgroup_ctr == 0) {
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
main->buffer[ci] = (*cinfo->mem->access_virt_sarray)
((j_common_ptr) cinfo, main->whole_image[ci],
main->cur_iMCU_row * (compptr->v_samp_factor * DCTSIZE),
(JDIMENSION) (compptr->v_samp_factor * DCTSIZE), writing);
}
/* In a read pass, pretend we just read some source data. */
if (! writing) {
*in_row_ctr += cinfo->max_v_samp_factor * DCTSIZE;
main->rowgroup_ctr = DCTSIZE;
}
}
/* If a write pass, read input data until the current iMCU row is full. */
/* Note: preprocessor will pad if necessary to fill the last iMCU row. */
if (writing) {
(*cinfo->prep->pre_process_data) (cinfo,
input_buf, in_row_ctr, in_rows_avail,
main->buffer, &main->rowgroup_ctr,
(JDIMENSION) DCTSIZE);
/* Return to application if we need more data to fill the iMCU row. */
if (main->rowgroup_ctr < DCTSIZE)
return;
}
/* Emit data, unless this is a sink-only pass. */
if (main->pass_mode != JBUF_SAVE_SOURCE) {
if (! (*cinfo->coef->compress_data) (cinfo, main->buffer)) {
/* If compressor did not consume the whole row, then we must need to
* suspend processing and return to the application. In this situation
* we pretend we didn't yet consume the last input row; otherwise, if
* it happened to be the last row of the image, the application would
* think we were done.
*/
if (! main->suspended) {
(*in_row_ctr)--;
main->suspended = TRUE;
}
return;
}
/* We did finish the row. Undo our little suspension hack if a previous
* call suspended; then mark the main buffer empty.
*/
if (main->suspended) {
(*in_row_ctr)++;
main->suspended = FALSE;
}
}
/* If get here, we are done with this iMCU row. Mark buffer empty. */
main->rowgroup_ctr = 0;
main->cur_iMCU_row++;
}
}
#endif /* FULL_MAIN_BUFFER_SUPPORTED */
/*
* Initialize main buffer controller.
*/
GLOBAL(void)
jinit_c_main_controller (j_compress_ptr cinfo, int need_full_buffer)
{
my_main_ptr main;
int ci;
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_c_main_controller *) main;
main->pub.start_pass = start_pass_main;
/* We don't need to create a buffer in raw-data mode. */
if (cinfo->raw_data_in)
return;
/* Create the buffer. It holds downsampled data, so each component
* may be of a different size.
*/
if (need_full_buffer) {
#ifdef FULL_MAIN_BUFFER_SUPPORTED
/* Allocate a full-image virtual array for each component */
/* Note we pad the bottom to a multiple of the iMCU height */
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
main->whole_image[ci] = (*cinfo->mem->request_virt_sarray)
((j_common_ptr) cinfo, JPOOL_IMAGE, FALSE,
compptr->width_in_blocks * DCTSIZE,
(JDIMENSION) jround_up((long) compptr->height_in_blocks,
(long) compptr->v_samp_factor) * DCTSIZE,
(JDIMENSION) (compptr->v_samp_factor * DCTSIZE));
}
#else
ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
#endif
} else {
#ifdef FULL_MAIN_BUFFER_SUPPORTED
main->whole_image[0] = NULL; /* flag for no virtual arrays */
#endif
/* Allocate a strip buffer for each component */
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
main->buffer[ci] = (*cinfo->mem->alloc_sarray)
((j_common_ptr) cinfo, JPOOL_IMAGE,
compptr->width_in_blocks * DCTSIZE,
(JDIMENSION) (compptr->v_samp_factor * DCTSIZE));
}
}
}
dlib/external/libjpeg/jcmarker.cpp 0 → 100644
View file @ 747088ea
/*
* jcmarker.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 write JPEG datastream markers.
*/
#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_writer pub; /* public fields */
unsigned int last_restart_interval; /* last DRI value emitted; 0 after SOI */
} my_marker_writer;
typedef my_marker_writer * my_marker_ptr;
/*
* Basic output routines.
*
* Note that we do not support suspension while writing a marker.
* Therefore, an application using suspension must ensure that there is
* enough buffer space for the initial markers (typ. 600-700 bytes) before
* calling jpeg_start_compress, and enough space to write the trailing EOI
* (a few bytes) before calling jpeg_finish_compress. Multipass compression
* modes are not supported at all with suspension, so those two are the only
* points where markers will be written.
*/
LOCAL(void)
emit_byte (j_compress_ptr cinfo, int val)
/* Emit a byte */
{
struct jpeg_destination_mgr * dest = cinfo->dest;
*(dest->next_output_byte)++ = (JOCTET) val;
if (--dest->free_in_buffer == 0) {
if (! (*dest->empty_output_buffer) (cinfo))
ERREXIT(cinfo, JERR_CANT_SUSPEND);
}
}
LOCAL(void)
emit_marker (j_compress_ptr cinfo, JPEG_MARKER mark)
/* Emit a marker code */
{
emit_byte(cinfo, 0xFF);
emit_byte(cinfo, (int) mark);
}
LOCAL(void)
emit_2bytes (j_compress_ptr cinfo, int value)
/* Emit a 2-byte integer; these are always MSB first in JPEG files */
{
emit_byte(cinfo, (value >> 8) & 0xFF);
emit_byte(cinfo, value & 0xFF);
}
/*
* Routines to write specific marker types.
*/
LOCAL(int)
emit_dqt (j_compress_ptr cinfo, int index)
/* Emit a DQT marker */
/* Returns the precision used (0 = 8bits, 1 = 16bits) for baseline checking */
{
JQUANT_TBL * qtbl = cinfo->quant_tbl_ptrs[index];
int prec;
int i;
if (qtbl == NULL)
ERREXIT1(cinfo, JERR_NO_QUANT_TABLE, index);
prec = 0;
for (i = 0; i < DCTSIZE2; i++) {
if (qtbl->quantval[i] > 255)
prec = 1;
}
if (! qtbl->sent_table) {
emit_marker(cinfo, M_DQT);
emit_2bytes(cinfo, prec ? DCTSIZE2*2 + 1 + 2 : DCTSIZE2 + 1 + 2);
emit_byte(cinfo, index + (prec<<4));
for (i = 0; i < DCTSIZE2; i++) {
/* The table entries must be emitted in zigzag order. */
unsigned int qval = qtbl->quantval[jpeg_natural_order[i]];
if (prec)
emit_byte(cinfo, (int) (qval >> 8));
emit_byte(cinfo, (int) (qval & 0xFF));
}
qtbl->sent_table = TRUE;
}
return prec;
}
LOCAL(void)
emit_dht (j_compress_ptr cinfo, int index, int is_ac)
/* Emit a DHT marker */
{
JHUFF_TBL * htbl;
int length, i;
if (is_ac) {
htbl = cinfo->ac_huff_tbl_ptrs[index];
index += 0x10; /* output index has AC bit set */
} else {
htbl = cinfo->dc_huff_tbl_ptrs[index];
}
if (htbl == NULL)
ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, index);
if (! htbl->sent_table) {
emit_marker(cinfo, M_DHT);
length = 0;
for (i = 1; i <= 16; i++)
length += htbl->bits[i];
emit_2bytes(cinfo, length + 2 + 1 + 16);
emit_byte(cinfo, index);
for (i = 1; i <= 16; i++)
emit_byte(cinfo, htbl->bits[i]);
for (i = 0; i < length; i++)
emit_byte(cinfo, htbl->huffval[i]);
htbl->sent_table = TRUE;
}
}
LOCAL(void)
emit_dac (j_compress_ptr cinfo)
/* Emit a DAC marker */
/* Since the useful info is so small, we want to emit all the tables in */
/* one DAC marker. Therefore this routine does its own scan of the table. */
{
#ifdef C_ARITH_CODING_SUPPORTED
char dc_in_use[NUM_ARITH_TBLS];
char ac_in_use[NUM_ARITH_TBLS];
int length, i;
jpeg_component_info *compptr;
for (i = 0; i < NUM_ARITH_TBLS; i++)
dc_in_use[i] = ac_in_use[i] = 0;
for (i = 0; i < cinfo->comps_in_scan; i++) {
compptr = cinfo->cur_comp_info[i];
dc_in_use[compptr->dc_tbl_no] = 1;
ac_in_use[compptr->ac_tbl_no] = 1;
}
length = 0;
for (i = 0; i < NUM_ARITH_TBLS; i++)
length += dc_in_use[i] + ac_in_use[i];
emit_marker(cinfo, M_DAC);
emit_2bytes(cinfo, length*2 + 2);
for (i = 0; i < NUM_ARITH_TBLS; i++) {
if (dc_in_use[i]) {
emit_byte(cinfo, i);
emit_byte(cinfo, cinfo->arith_dc_L[i] + (cinfo->arith_dc_U[i]<<4));
}
if (ac_in_use[i]) {
emit_byte(cinfo, i + 0x10);
emit_byte(cinfo, cinfo->arith_ac_K[i]);
}
}
#endif /* C_ARITH_CODING_SUPPORTED */
}
LOCAL(void)
emit_dri (j_compress_ptr cinfo)
/* Emit a DRI marker */
{
emit_marker(cinfo, M_DRI);
emit_2bytes(cinfo, 4); /* fixed length */
emit_2bytes(cinfo, (int) cinfo->restart_interval);
}
LOCAL(void)
emit_sof (j_compress_ptr cinfo, JPEG_MARKER code)
/* Emit a SOF marker */
{
int ci;
jpeg_component_info *compptr;
emit_marker(cinfo, code);
emit_2bytes(cinfo, 3 * cinfo->num_components + 2 + 5 + 1); /* length */
/* Make sure image isn't bigger than SOF field can handle */
if ((long) cinfo->image_height > 65535L ||
(long) cinfo->image_width > 65535L)
ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) 65535);
emit_byte(cinfo, cinfo->data_precision);
emit_2bytes(cinfo, (int) cinfo->image_height);
emit_2bytes(cinfo, (int) cinfo->image_width);
emit_byte(cinfo, cinfo->num_components);
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
emit_byte(cinfo, compptr->component_id);
emit_byte(cinfo, (compptr->h_samp_factor << 4) + compptr->v_samp_factor);
emit_byte(cinfo, compptr->quant_tbl_no);
}
}
LOCAL(void)
emit_sos (j_compress_ptr cinfo)
/* Emit a SOS marker */
{
int i, td, ta;
jpeg_component_info *compptr;
emit_marker(cinfo, M_SOS);
emit_2bytes(cinfo, 2 * cinfo->comps_in_scan + 2 + 1 + 3); /* length */
emit_byte(cinfo, cinfo->comps_in_scan);
for (i = 0; i < cinfo->comps_in_scan; i++) {
compptr = cinfo->cur_comp_info[i];
emit_byte(cinfo, compptr->component_id);
td = compptr->dc_tbl_no;
ta = compptr->ac_tbl_no;
if (cinfo->progressive_mode) {
/* Progressive mode: only DC or only AC tables are used in one scan;
* furthermore, Huffman coding of DC refinement uses no table at all.
* We emit 0 for unused field(s); this is recommended by the P&M text
* but does not seem to be specified in the standard.
*/
if (cinfo->Ss == 0) {
ta = 0; /* DC scan */
if (cinfo->Ah != 0 && !cinfo->arith_code)
td = 0; /* no DC table either */
} else {
td = 0; /* AC scan */
}
}
emit_byte(cinfo, (td << 4) + ta);
}
emit_byte(cinfo, cinfo->Ss);
emit_byte(cinfo, cinfo->Se);
emit_byte(cinfo, (cinfo->Ah << 4) + cinfo->Al);
}
LOCAL(void)
emit_jfif_app0 (j_compress_ptr cinfo)
/* Emit a JFIF-compliant APP0 marker */
{
/*
* Length of APP0 block (2 bytes)
* Block ID (4 bytes - ASCII "JFIF")
* Zero byte (1 byte to terminate the ID string)
* Version Major, Minor (2 bytes - major first)
* Units (1 byte - 0x00 = none, 0x01 = inch, 0x02 = cm)
* Xdpu (2 bytes - dots per unit horizontal)
* Ydpu (2 bytes - dots per unit vertical)
* Thumbnail X size (1 byte)
* Thumbnail Y size (1 byte)
*/
emit_marker(cinfo, M_APP0);
emit_2bytes(cinfo, 2 + 4 + 1 + 2 + 1 + 2 + 2 + 1 + 1); /* length */
emit_byte(cinfo, 0x4A); /* Identifier: ASCII "JFIF" */
emit_byte(cinfo, 0x46);
emit_byte(cinfo, 0x49);
emit_byte(cinfo, 0x46);
emit_byte(cinfo, 0);
emit_byte(cinfo, cinfo->JFIF_major_version); /* Version fields */
emit_byte(cinfo, cinfo->JFIF_minor_version);
emit_byte(cinfo, cinfo->density_unit); /* Pixel size information */
emit_2bytes(cinfo, (int) cinfo->X_density);
emit_2bytes(cinfo, (int) cinfo->Y_density);
emit_byte(cinfo, 0); /* No thumbnail image */
emit_byte(cinfo, 0);
}
LOCAL(void)
emit_adobe_app14 (j_compress_ptr cinfo)
/* Emit an Adobe APP14 marker */
{
/*
* Length of APP14 block (2 bytes)
* Block ID (5 bytes - ASCII "Adobe")
* Version Number (2 bytes - currently 100)
* Flags0 (2 bytes - currently 0)
* Flags1 (2 bytes - currently 0)
* Color transform (1 byte)
*
* Although Adobe TN 5116 mentions Version = 101, all the Adobe files
* now in circulation seem to use Version = 100, so that's what we write.
*
* We write the color transform byte as 1 if the JPEG color space is
* YCbCr, 2 if it's YCCK, 0 otherwise. Adobe's definition has to do with
* whether the encoder performed a transformation, which is pretty useless.
*/
emit_marker(cinfo, M_APP14);
emit_2bytes(cinfo, 2 + 5 + 2 + 2 + 2 + 1); /* length */
emit_byte(cinfo, 0x41); /* Identifier: ASCII "Adobe" */
emit_byte(cinfo, 0x64);
emit_byte(cinfo, 0x6F);
emit_byte(cinfo, 0x62);
emit_byte(cinfo, 0x65);
emit_2bytes(cinfo, 100); /* Version */
emit_2bytes(cinfo, 0); /* Flags0 */
emit_2bytes(cinfo, 0); /* Flags1 */
switch (cinfo->jpeg_color_space) {
case JCS_YCbCr:
emit_byte(cinfo, 1); /* Color transform = 1 */
break;
case JCS_YCCK:
emit_byte(cinfo, 2); /* Color transform = 2 */
break;
default:
emit_byte(cinfo, 0); /* Color transform = 0 */
break;
}
}
/*
* These routines allow writing an arbitrary marker with parameters.
* The only intended use is to emit COM or APPn markers after calling
* write_file_header and before calling write_frame_header.
* Other uses are not guaranteed to produce desirable results.
* Counting the parameter bytes properly is the caller's responsibility.
*/
METHODDEF(void)
write_marker_header (j_compress_ptr cinfo, int marker, unsigned int datalen)
/* Emit an arbitrary marker header */
{
if (datalen > (unsigned int) 65533) /* safety check */
ERREXIT(cinfo, JERR_BAD_LENGTH);
emit_marker(cinfo, (JPEG_MARKER) marker);
emit_2bytes(cinfo, (int) (datalen + 2)); /* total length */
}
METHODDEF(void)
write_marker_byte (j_compress_ptr cinfo, int val)
/* Emit one byte of marker parameters following write_marker_header */
{
emit_byte(cinfo, val);
}
/*
* Write datastream header.
* This consists of an SOI and optional APPn markers.
* We recommend use of the JFIF marker, but not the Adobe marker,
* when using YCbCr or grayscale data. The JFIF marker should NOT
* be used for any other JPEG colorspace. The Adobe marker is helpful
* to distinguish RGB, CMYK, and YCCK colorspaces.
* Note that an application can write additional header markers after
* jpeg_start_compress returns.
*/
METHODDEF(void)
write_file_header (j_compress_ptr cinfo)
{
my_marker_ptr marker = (my_marker_ptr) cinfo->marker;
emit_marker(cinfo, M_SOI); /* first the SOI */
/* SOI is defined to reset restart interval to 0 */
marker->last_restart_interval = 0;
if (cinfo->write_JFIF_header) /* next an optional JFIF APP0 */
emit_jfif_app0(cinfo);
if (cinfo->write_Adobe_marker) /* next an optional Adobe APP14 */
emit_adobe_app14(cinfo);
}
/*
* Write frame header.
* This consists of DQT and SOFn markers.
* Note that we do not emit the SOF until we have emitted the DQT(s).
* This avoids compatibility problems with incorrect implementations that
* try to error-check the quant table numbers as soon as they see the SOF.
*/
METHODDEF(void)
write_frame_header (j_compress_ptr cinfo)
{
int ci, prec;
int is_baseline;
jpeg_component_info *compptr;
/* Emit DQT for each quantization table.
* Note that emit_dqt() suppresses any duplicate tables.
*/
prec = 0;
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
prec += emit_dqt(cinfo, compptr->quant_tbl_no);
}
/* now prec is nonzero iff there are any 16-bit quant tables. */
/* Check for a non-baseline specification.
* Note we assume that Huffman table numbers won't be changed later.
*/
if (cinfo->arith_code || cinfo->progressive_mode ||
cinfo->data_precision != 8) {
is_baseline = FALSE;
} else {
is_baseline = TRUE;
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
if (compptr->dc_tbl_no > 1 || compptr->ac_tbl_no > 1)
is_baseline = FALSE;
}
if (prec && is_baseline) {
is_baseline = FALSE;
/* If it's baseline except for quantizer size, warn the user */
TRACEMS(cinfo, 0, JTRC_16BIT_TABLES);
}
}
/* Emit the proper SOF marker */
if (cinfo->arith_code) {
emit_sof(cinfo, M_SOF9); /* SOF code for arithmetic coding */
} else {
if (cinfo->progressive_mode)
emit_sof(cinfo, M_SOF2); /* SOF code for progressive Huffman */
else if (is_baseline)
emit_sof(cinfo, M_SOF0); /* SOF code for baseline implementation */
else
emit_sof(cinfo, M_SOF1); /* SOF code for non-baseline Huffman file */
}
}
/*
* Write scan header.
* This consists of DHT or DAC markers, optional DRI, and SOS.
* Compressed data will be written following the SOS.
*/
METHODDEF(void)
write_scan_header (j_compress_ptr cinfo)
{
my_marker_ptr marker = (my_marker_ptr) cinfo->marker;
int i;
jpeg_component_info *compptr;
if (cinfo->arith_code) {
/* Emit arith conditioning info. We may have some duplication
* if the file has multiple scans, but it's so small it's hardly
* worth worrying about.
*/
emit_dac(cinfo);
} else {
/* Emit Huffman tables.
* Note that emit_dht() suppresses any duplicate tables.
*/
for (i = 0; i < cinfo->comps_in_scan; i++) {
compptr = cinfo->cur_comp_info[i];
if (cinfo->progressive_mode) {
/* Progressive mode: only DC or only AC tables are used in one scan */
if (cinfo->Ss == 0) {
if (cinfo->Ah == 0) /* DC needs no table for refinement scan */
emit_dht(cinfo, compptr->dc_tbl_no, FALSE);
} else {
emit_dht(cinfo, compptr->ac_tbl_no, TRUE);
}
} else {
/* Sequential mode: need both DC and AC tables */
emit_dht(cinfo, compptr->dc_tbl_no, FALSE);
emit_dht(cinfo, compptr->ac_tbl_no, TRUE);
}
}
}
/* Emit DRI if required --- note that DRI value could change for each scan.
* We avoid wasting space with unnecessary DRIs, however.
*/
if (cinfo->restart_interval != marker->last_restart_interval) {
emit_dri(cinfo);
marker->last_restart_interval = cinfo->restart_interval;
}
emit_sos(cinfo);
}
/*
* Write datastream trailer.
*/
METHODDEF(void)
write_file_trailer (j_compress_ptr cinfo)
{
emit_marker(cinfo, M_EOI);
}
/*
* Write an abbreviated table-specification datastream.
* This consists of SOI, DQT and DHT tables, and EOI.
* Any table that is defined and not marked sent_table = TRUE will be
* emitted. Note that all tables will be marked sent_table = TRUE at exit.
*/
METHODDEF(void)
write_tables_only (j_compress_ptr cinfo)
{
int i;
emit_marker(cinfo, M_SOI);
for (i = 0; i < NUM_QUANT_TBLS; i++) {
if (cinfo->quant_tbl_ptrs[i] != NULL)
(void) emit_dqt(cinfo, i);
}
if (! cinfo->arith_code) {
for (i = 0; i < NUM_HUFF_TBLS; i++) {
if (cinfo->dc_huff_tbl_ptrs[i] != NULL)
emit_dht(cinfo, i, FALSE);
if (cinfo->ac_huff_tbl_ptrs[i] != NULL)
emit_dht(cinfo, i, TRUE);
}
}
emit_marker(cinfo, M_EOI);
}
/*
* Initialize the marker writer module.
*/
GLOBAL(void)
jinit_marker_writer (j_compress_ptr cinfo)
{
my_marker_ptr marker;
/* Create the subobject */
marker = (my_marker_ptr)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
SIZEOF(my_marker_writer));
cinfo->marker = (struct jpeg_marker_writer *) marker;
/* Initialize method pointers */
marker->pub.write_file_header = write_file_header;
marker->pub.write_frame_header = write_frame_header;
marker->pub.write_scan_header = write_scan_header;
marker->pub.write_file_trailer = write_file_trailer;
marker->pub.write_tables_only = write_tables_only;
marker->pub.write_marker_header = write_marker_header;
marker->pub.write_marker_byte = write_marker_byte;
/* Initialize private state */
marker->last_restart_interval = 0;
}
dlib/external/libjpeg/jcmaster.cpp 0 → 100644
View file @ 747088ea
/*
* jcmaster.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 compressor.
* These routines are concerned with parameter validation, initial setup,
* and inter-pass control (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 enum {
main_pass, /* input data, also do first output step */
huff_opt_pass, /* Huffman code optimization pass */
output_pass /* data output pass */
} c_pass_type;
typedef struct {
struct jpeg_comp_master pub; /* public fields */
c_pass_type pass_type; /* the type of the current pass */
int pass_number; /* # of passes completed */
int total_passes; /* total # of passes needed */
int scan_number; /* current index in scan_info[] */
} my_comp_master;
typedef my_comp_master * my_master_ptr;
/*
* Support routines that do various essential calculations.
*/
LOCAL(void)
initial_setup (j_compress_ptr cinfo)
/* Do computations that are needed before master selection phase */
{
int ci;
jpeg_component_info *compptr;
long samplesperrow;
JDIMENSION jd_samplesperrow;
/* Sanity check on image dimensions */
if (cinfo->image_height <= 0 || cinfo->image_width <= 0
|| cinfo->num_components <= 0 || cinfo->input_components <= 0)
ERREXIT(cinfo, JERR_EMPTY_IMAGE);
/* 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);
/* Width of an input scanline must be representable as JDIMENSION. */
samplesperrow = (long) cinfo->image_width * (long) cinfo->input_components;
jd_samplesperrow = (JDIMENSION) samplesperrow;
if ((long) jd_samplesperrow != samplesperrow)
ERREXIT(cinfo, JERR_WIDTH_OVERFLOW);
/* 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);
}
/* Compute dimensions of components */
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
/* Fill in the correct component_index value; don't rely on application */
compptr->component_index = ci;
/* For compression, we never do DCT scaling. */
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));
/* 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 (this flag isn't actually used for compression) */
compptr->component_needed = TRUE;
}
/* Compute number of fully interleaved MCU rows (number of times that
* main controller will call coefficient controller).
*/
cinfo->total_iMCU_rows = (JDIMENSION)
jdiv_round_up((long) cinfo->image_height,
(long) (cinfo->max_v_samp_factor*DCTSIZE));
}
#ifdef C_MULTISCAN_FILES_SUPPORTED
LOCAL(void)
validate_script (j_compress_ptr cinfo)
/* Verify that the scan script in cinfo->scan_info[] is valid; also
* determine whether it uses progressive JPEG, and set cinfo->progressive_mode.
*/
{
const jpeg_scan_info * scanptr;
int scanno, ncomps, ci, coefi, thisi;
int Ss, Se, Ah, Al;
int component_sent[MAX_COMPONENTS];
#ifdef C_PROGRESSIVE_SUPPORTED
int * last_bitpos_ptr;
int last_bitpos[MAX_COMPONENTS][DCTSIZE2];
/* -1 until that coefficient has been seen; then last Al for it */
#endif
if (cinfo->num_scans <= 0)
ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, 0);
/* For sequential JPEG, all scans must have Ss=0, Se=DCTSIZE2-1;
* for progressive JPEG, no scan can have this.
*/
scanptr = cinfo->scan_info;
if (scanptr->Ss != 0 || scanptr->Se != DCTSIZE2-1) {
#ifdef C_PROGRESSIVE_SUPPORTED
cinfo->progressive_mode = TRUE;
last_bitpos_ptr = & last_bitpos[0][0];
for (ci = 0; ci < cinfo->num_components; ci++)
for (coefi = 0; coefi < DCTSIZE2; coefi++)
*last_bitpos_ptr++ = -1;
#else
ERREXIT(cinfo, JERR_NOT_COMPILED);
#endif
} else {
cinfo->progressive_mode = FALSE;
for (ci = 0; ci < cinfo->num_components; ci++)
component_sent[ci] = FALSE;
}
for (scanno = 1; scanno <= cinfo->num_scans; scanptr++, scanno++) {
/* Validate component indexes */
ncomps = scanptr->comps_in_scan;
if (ncomps <= 0 || ncomps > MAX_COMPS_IN_SCAN)
ERREXIT2(cinfo, JERR_COMPONENT_COUNT, ncomps, MAX_COMPS_IN_SCAN);
for (ci = 0; ci < ncomps; ci++) {
thisi = scanptr->component_index[ci];
if (thisi < 0 || thisi >= cinfo->num_components)
ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno);
/* Components must appear in SOF order within each scan */
if (ci > 0 && thisi <= scanptr->component_index[ci-1])
ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno);
}
/* Validate progression parameters */
Ss = scanptr->Ss;
Se = scanptr->Se;
Ah = scanptr->Ah;
Al = scanptr->Al;
if (cinfo->progressive_mode) {
#ifdef C_PROGRESSIVE_SUPPORTED
/* The JPEG spec simply gives the ranges 0..13 for Ah and Al, but that
* seems wrong: the upper bound ought to depend on data precision.
* Perhaps they really meant 0..N+1 for N-bit precision.
* Here we allow 0..10 for 8-bit data; Al larger than 10 results in
* out-of-range reconstructed DC values during the first DC scan,
* which might cause problems for some decoders.
*/
#if BITS_IN_JSAMPLE == 8
#define MAX_AH_AL 10
#else
#define MAX_AH_AL 13
#endif
if (Ss < 0 || Ss >= DCTSIZE2 || Se < Ss || Se >= DCTSIZE2 ||
Ah < 0 || Ah > MAX_AH_AL || Al < 0 || Al > MAX_AH_AL)
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
if (Ss == 0) {
if (Se != 0) /* DC and AC together not OK */
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
} else {
if (ncomps != 1) /* AC scans must be for only one component */
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
}
for (ci = 0; ci < ncomps; ci++) {
last_bitpos_ptr = & last_bitpos[scanptr->component_index[ci]][0];
if (Ss != 0 && last_bitpos_ptr[0] < 0) /* AC without prior DC scan */
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
for (coefi = Ss; coefi <= Se; coefi++) {
if (last_bitpos_ptr[coefi] < 0) {
/* first scan of this coefficient */
if (Ah != 0)
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
} else {
/* not first scan */
if (Ah != last_bitpos_ptr[coefi] || Al != Ah-1)
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
}
last_bitpos_ptr[coefi] = Al;
}
}
#endif
} else {
/* For sequential JPEG, all progression parameters must be these: */
if (Ss != 0 || Se != DCTSIZE2-1 || Ah != 0 || Al != 0)
ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
/* Make sure components are not sent twice */
for (ci = 0; ci < ncomps; ci++) {
thisi = scanptr->component_index[ci];
if (component_sent[thisi])
ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno);
component_sent[thisi] = TRUE;
}
}
}
/* Now verify that everything got sent. */
if (cinfo->progressive_mode) {
#ifdef C_PROGRESSIVE_SUPPORTED
/* For progressive mode, we only check that at least some DC data
* got sent for each component; the spec does not require that all bits
* of all coefficients be transmitted. Would it be wiser to enforce
* transmission of all coefficient bits??
*/
for (ci = 0; ci < cinfo->num_components; ci++) {
if (last_bitpos[ci][0] < 0)
ERREXIT(cinfo, JERR_MISSING_DATA);
}
#endif
} else {
for (ci = 0; ci < cinfo->num_components; ci++) {
if (! component_sent[ci])
ERREXIT(cinfo, JERR_MISSING_DATA);
}
}
}
#endif /* C_MULTISCAN_FILES_SUPPORTED */
LOCAL(void)
select_scan_parameters (j_compress_ptr cinfo)
/* Set up the scan parameters for the current scan */
{
int ci;
#ifdef C_MULTISCAN_FILES_SUPPORTED
if (cinfo->scan_info != NULL) {
/* Prepare for current scan --- the script is already validated */
my_master_ptr master = (my_master_ptr) cinfo->master;
const jpeg_scan_info * scanptr = cinfo->scan_info + master->scan_number;
cinfo->comps_in_scan = scanptr->comps_in_scan;
for (ci = 0; ci < scanptr->comps_in_scan; ci++) {
cinfo->cur_comp_info[ci] =
&cinfo->comp_info[scanptr->component_index[ci]];
}
cinfo->Ss = scanptr->Ss;
cinfo->Se = scanptr->Se;
cinfo->Ah = scanptr->Ah;
cinfo->Al = scanptr->Al;
}
else
#endif
{
/* Prepare for single sequential-JPEG scan containing all components */
if (cinfo->num_components > MAX_COMPS_IN_SCAN)
ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,
MAX_COMPS_IN_SCAN);
cinfo->comps_in_scan = cinfo->num_components;
for (ci = 0; ci < cinfo->num_components; ci++) {
cinfo->cur_comp_info[ci] = &cinfo->comp_info[ci];
}
cinfo->Ss = 0;
cinfo->Se = DCTSIZE2-1;
cinfo->Ah = 0;
cinfo->Al = 0;
}
}
LOCAL(void)
per_scan_setup (j_compress_ptr cinfo)
/* Do computations that are needed before processing a JPEG scan */
/* cinfo->comps_in_scan and cinfo->cur_comp_info[] are already set */
{
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 = DCTSIZE;
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 * DCTSIZE;
/* 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 > C_MAX_BLOCKS_IN_MCU)
ERREXIT(cinfo, JERR_BAD_MCU_SIZE);
while (mcublks-- > 0) {
cinfo->MCU_membership[cinfo->blocks_in_MCU++] = ci;
}
}
}
/* Convert restart specified in rows to actual MCU count. */
/* Note that count must fit in 16 bits, so we provide limiting. */
if (cinfo->restart_in_rows > 0) {
long nominal = (long) cinfo->restart_in_rows * (long) cinfo->MCUs_per_row;
cinfo->restart_interval = (unsigned int) MIN(nominal, 65535L);
}
}
/*
* Per-pass setup.
* This is called at the beginning of each pass. We determine which modules
* will be active during this pass and give them appropriate start_pass calls.
* We also set is_last_pass to indicate whether any more passes will be
* required.
*/
METHODDEF(void)
prepare_for_pass (j_compress_ptr cinfo)
{
my_master_ptr master = (my_master_ptr) cinfo->master;
switch (master->pass_type) {
case main_pass:
/* Initial pass: will collect input data, and do either Huffman
* optimization or data output for the first scan.
*/
select_scan_parameters(cinfo);
per_scan_setup(cinfo);
if (! cinfo->raw_data_in) {
(*cinfo->cconvert->start_pass) (cinfo);
(*cinfo->downsample->start_pass) (cinfo);
(*cinfo->prep->start_pass) (cinfo, JBUF_PASS_THRU);
}
(*cinfo->fdct->start_pass) (cinfo);
(*cinfo->entropy->start_pass) (cinfo, cinfo->optimize_coding);
(*cinfo->coef->start_pass) (cinfo,
(master->total_passes > 1 ?
JBUF_SAVE_AND_PASS : JBUF_PASS_THRU));
(*cinfo->main->start_pass) (cinfo, JBUF_PASS_THRU);
if (cinfo->optimize_coding) {
/* No immediate data output; postpone writing frame/scan headers */
master->pub.call_pass_startup = FALSE;
} else {
/* Will write frame/scan headers at first jpeg_write_scanlines call */
master->pub.call_pass_startup = TRUE;
}
break;
#ifdef ENTROPY_OPT_SUPPORTED
case huff_opt_pass:
/* Do Huffman optimization for a scan after the first one. */
select_scan_parameters(cinfo);
per_scan_setup(cinfo);
if (cinfo->Ss != 0 || cinfo->Ah == 0 || cinfo->arith_code) {
(*cinfo->entropy->start_pass) (cinfo, TRUE);
(*cinfo->coef->start_pass) (cinfo, JBUF_CRANK_DEST);
master->pub.call_pass_startup = FALSE;
break;
}
/* Special case: Huffman DC refinement scans need no Huffman table
* and therefore we can skip the optimization pass for them.
*/
master->pass_type = output_pass;
master->pass_number++;
/*FALLTHROUGH*/
#endif
case output_pass:
/* Do a data-output pass. */
/* We need not repeat per-scan setup if prior optimization pass did it. */
if (! cinfo->optimize_coding) {
select_scan_parameters(cinfo);
per_scan_setup(cinfo);
}
(*cinfo->entropy->start_pass) (cinfo, FALSE);
(*cinfo->coef->start_pass) (cinfo, JBUF_CRANK_DEST);
/* We emit frame/scan headers now */
if (master->scan_number == 0)
(*cinfo->marker->write_frame_header) (cinfo);
(*cinfo->marker->write_scan_header) (cinfo);
master->pub.call_pass_startup = FALSE;
break;
default:
ERREXIT(cinfo, JERR_NOT_COMPILED);
}
master->pub.is_last_pass = (master->pass_number == master->total_passes-1);
/* 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->total_passes;
}
}
/*
* Special start-of-pass hook.
* This is called by jpeg_write_scanlines if call_pass_startup is TRUE.
* In single-pass processing, we need this hook because we don't want to
* write frame/scan headers during jpeg_start_compress; we want to let the
* application write COM markers etc. between jpeg_start_compress and the
* jpeg_write_scanlines loop.
* In multi-pass processing, this routine is not used.
*/
METHODDEF(void)
pass_startup (j_compress_ptr cinfo)
{
cinfo->master->call_pass_startup = FALSE; /* reset flag so call only once */
(*cinfo->marker->write_frame_header) (cinfo);
(*cinfo->marker->write_scan_header) (cinfo);
}
/*
* Finish up at end of pass.
*/
METHODDEF(void)
finish_pass_master (j_compress_ptr cinfo)
{
my_master_ptr master = (my_master_ptr) cinfo->master;
/* The entropy coder always needs an end-of-pass call,
* either to analyze statistics or to flush its output buffer.
*/
(*cinfo->entropy->finish_pass) (cinfo);
/* Update state for next pass */
switch (master->pass_type) {
case main_pass:
/* next pass is either output of scan 0 (after optimization)
* or output of scan 1 (if no optimization).
*/
master->pass_type = output_pass;
if (! cinfo->optimize_coding)
master->scan_number++;
break;
case huff_opt_pass:
/* next pass is always output of current scan */
master->pass_type = output_pass;
break;
case output_pass:
/* next pass is either optimization or output of next scan */
if (cinfo->optimize_coding)
master->pass_type = huff_opt_pass;
master->scan_number++;
break;
}
master->pass_number++;
}
/*
* Initialize master compression control.
*/
GLOBAL(void)
jinit_c_master_control (j_compress_ptr cinfo, int transcode_only)
{
my_master_ptr master;
master = (my_master_ptr)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
SIZEOF(my_comp_master));
cinfo->master = (struct jpeg_comp_master *) master;
master->pub.prepare_for_pass = prepare_for_pass;
master->pub.pass_startup = pass_startup;
master->pub.finish_pass = finish_pass_master;
master->pub.is_last_pass = FALSE;
/* Validate parameters, determine derived values */
initial_setup(cinfo);
if (cinfo->scan_info != NULL) {
#ifdef C_MULTISCAN_FILES_SUPPORTED
validate_script(cinfo);
#else
ERREXIT(cinfo, JERR_NOT_COMPILED);
#endif
} else {
cinfo->progressive_mode = FALSE;
cinfo->num_scans = 1;
}
if (cinfo->progressive_mode) /* TEMPORARY HACK ??? */
cinfo->optimize_coding = TRUE; /* assume default tables no good for progressive mode */
/* Initialize my private state */
if (transcode_only) {
/* no main pass in transcoding */
if (cinfo->optimize_coding)
master->pass_type = huff_opt_pass;
else
master->pass_type = output_pass;
} else {
/* for normal compression, first pass is always this type: */
master->pass_type = main_pass;
}
master->scan_number = 0;
master->pass_number = 0;
if (cinfo->optimize_coding)
master->total_passes = cinfo->num_scans * 2;
else
master->total_passes = cinfo->num_scans;
}
dlib/external/libjpeg/jcparam.cpp 0 → 100644
View file @ 747088ea
/*
* jcparam.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 optional default-setting code for the JPEG compressor.
* Applications do not have to use this file, but those that don't use it
* must know a lot more about the innards of the JPEG code.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
/*
* Quantization table setup routines
*/
GLOBAL(void)
jpeg_add_quant_table (j_compress_ptr cinfo, int which_tbl,
const unsigned int *basic_table,
int scale_factor, int force_baseline)
/* Define a quantization table equal to the basic_table times
* a scale factor (given as a percentage).
* If force_baseline is TRUE, the computed quantization table entries
* are limited to 1..255 for JPEG baseline compatibility.
*/
{
JQUANT_TBL ** qtblptr;
int i;
long temp;
/* Safety check to ensure start_compress not called yet. */
if (cinfo->global_state != CSTATE_START)
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
if (which_tbl < 0 || which_tbl >= NUM_QUANT_TBLS)
ERREXIT1(cinfo, JERR_DQT_INDEX, which_tbl);
qtblptr = & cinfo->quant_tbl_ptrs[which_tbl];
if (*qtblptr == NULL)
*qtblptr = jpeg_alloc_quant_table((j_common_ptr) cinfo);
for (i = 0; i < DCTSIZE2; i++) {
temp = ((long) basic_table[i] * scale_factor + 50L) / 100L;
/* limit the values to the valid range */
if (temp <= 0L) temp = 1L;
if (temp > 32767L) temp = 32767L; /* max quantizer needed for 12 bits */
if (force_baseline && temp > 255L)
temp = 255L; /* limit to baseline range if requested */
(*qtblptr)->quantval[i] = (unsigned short) temp;
}
/* Initialize sent_table FALSE so table will be written to JPEG file. */
(*qtblptr)->sent_table = FALSE;
}
GLOBAL(void)
jpeg_set_linear_quality (j_compress_ptr cinfo, int scale_factor,
int force_baseline)
/* Set or change the 'quality' (quantization) setting, using default tables
* and a straight percentage-scaling quality scale. In most cases it's better
* to use jpeg_set_quality (below); this entry point is provided for
* applications that insist on a linear percentage scaling.
*/
{
/* These are the sample quantization tables given in JPEG spec section K.1.
* The spec says that the values given produce "good" quality, and
* when divided by 2, "very good" quality.
*/
static const unsigned int std_luminance_quant_tbl[DCTSIZE2] = {
16, 11, 10, 16, 24, 40, 51, 61,
12, 12, 14, 19, 26, 58, 60, 55,
14, 13, 16, 24, 40, 57, 69, 56,
14, 17, 22, 29, 51, 87, 80, 62,
18, 22, 37, 56, 68, 109, 103, 77,
24, 35, 55, 64, 81, 104, 113, 92,
49, 64, 78, 87, 103, 121, 120, 101,
72, 92, 95, 98, 112, 100, 103, 99
};
static const unsigned int std_chrominance_quant_tbl[DCTSIZE2] = {
17, 18, 24, 47, 99, 99, 99, 99,
18, 21, 26, 66, 99, 99, 99, 99,
24, 26, 56, 99, 99, 99, 99, 99,
47, 66, 99, 99, 99, 99, 99, 99,
99, 99, 99, 99, 99, 99, 99, 99,
99, 99, 99, 99, 99, 99, 99, 99,
99, 99, 99, 99, 99, 99, 99, 99,
99, 99, 99, 99, 99, 99, 99, 99
};
/* Set up two quantization tables using the specified scaling */
jpeg_add_quant_table(cinfo, 0, std_luminance_quant_tbl,
scale_factor, force_baseline);
jpeg_add_quant_table(cinfo, 1, std_chrominance_quant_tbl,
scale_factor, force_baseline);
}
GLOBAL(int)
jpeg_quality_scaling (int quality)
/* Convert a user-specified quality rating to a percentage scaling factor
* for an underlying quantization table, using our recommended scaling curve.
* The input 'quality' factor should be 0 (terrible) to 100 (very good).
*/
{
/* Safety limit on quality factor. Convert 0 to 1 to avoid zero divide. */
if (quality <= 0) quality = 1;
if (quality > 100) quality = 100;
/* The basic table is used as-is (scaling 100) for a quality of 50.
* Qualities 50..100 are converted to scaling percentage 200 - 2*Q;
* note that at Q=100 the scaling is 0, which will cause jpeg_add_quant_table
* to make all the table entries 1 (hence, minimum quantization loss).
* Qualities 1..50 are converted to scaling percentage 5000/Q.
*/
if (quality < 50)
quality = 5000 / quality;
else
quality = 200 - quality*2;
return quality;
}
GLOBAL(void)
jpeg_set_quality (j_compress_ptr cinfo, int quality, int force_baseline)
/* Set or change the 'quality' (quantization) setting, using default tables.
* This is the standard quality-adjusting entry point for typical user
* interfaces; only those who want detailed control over quantization tables
* would use the preceding three routines directly.
*/
{
/* Convert user 0-100 rating to percentage scaling */
quality = jpeg_quality_scaling(quality);
/* Set up standard quality tables */
jpeg_set_linear_quality(cinfo, quality, force_baseline);
}
/*
* Huffman table setup routines
*/
LOCAL(void)
add_huff_table (j_compress_ptr cinfo,
JHUFF_TBL **htblptr, const unsigned char *bits, const unsigned char *val)
/* Define a Huffman table */
{
int nsymbols, len;
if (*htblptr == NULL)
*htblptr = jpeg_alloc_huff_table((j_common_ptr) cinfo);
/* Copy the number-of-symbols-of-each-code-length counts */
MEMCOPY((*htblptr)->bits, bits, SIZEOF((*htblptr)->bits));
/* Validate the counts. We do this here mainly so we can copy the right
* number of symbols from the val[] array, without risking marching off
* the end of memory. jchuff.c will do a more thorough test later.
*/
nsymbols = 0;
for (len = 1; len <= 16; len++)
nsymbols += bits[len];
if (nsymbols < 1 || nsymbols > 256)
ERREXIT(cinfo, JERR_BAD_HUFF_TABLE);
MEMCOPY((*htblptr)->huffval, val, nsymbols * SIZEOF(unsigned char));
/* Initialize sent_table FALSE so table will be written to JPEG file. */
(*htblptr)->sent_table = FALSE;
}
LOCAL(void)
std_huff_tables (j_compress_ptr cinfo)
/* Set up the standard Huffman tables (cf. JPEG standard section K.3) */
/* IMPORTANT: these are only valid for 8-bit data precision! */
{
static const unsigned char bits_dc_luminance[17] =
{ /* 0-base */ 0, 0, 1, 5, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0 };
static const unsigned char val_dc_luminance[] =
{ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 };
static const unsigned char bits_dc_chrominance[17] =
{ /* 0-base */ 0, 0, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0 };
static const unsigned char val_dc_chrominance[] =
{ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 };
static const unsigned char bits_ac_luminance[17] =
{ /* 0-base */ 0, 0, 2, 1, 3, 3, 2, 4, 3, 5, 5, 4, 4, 0, 0, 1, 0x7d };
static const unsigned char val_ac_luminance[] =
{ 0x01, 0x02, 0x03, 0x00, 0x04, 0x11, 0x05, 0x12,
0x21, 0x31, 0x41, 0x06, 0x13, 0x51, 0x61, 0x07,
0x22, 0x71, 0x14, 0x32, 0x81, 0x91, 0xa1, 0x08,
0x23, 0x42, 0xb1, 0xc1, 0x15, 0x52, 0xd1, 0xf0,
0x24, 0x33, 0x62, 0x72, 0x82, 0x09, 0x0a, 0x16,
0x17, 0x18, 0x19, 0x1a, 0x25, 0x26, 0x27, 0x28,
0x29, 0x2a, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39,
0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49,
0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59,
0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69,
0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79,
0x7a, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89,
0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98,
0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,
0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6,
0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3, 0xc4, 0xc5,
0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4,
0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xe1, 0xe2,
0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea,
0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8,
0xf9, 0xfa };
static const unsigned char bits_ac_chrominance[17] =
{ /* 0-base */ 0, 0, 2, 1, 2, 4, 4, 3, 4, 7, 5, 4, 4, 0, 1, 2, 0x77 };
static const unsigned char val_ac_chrominance[] =
{ 0x00, 0x01, 0x02, 0x03, 0x11, 0x04, 0x05, 0x21,
0x31, 0x06, 0x12, 0x41, 0x51, 0x07, 0x61, 0x71,
0x13, 0x22, 0x32, 0x81, 0x08, 0x14, 0x42, 0x91,
0xa1, 0xb1, 0xc1, 0x09, 0x23, 0x33, 0x52, 0xf0,
0x15, 0x62, 0x72, 0xd1, 0x0a, 0x16, 0x24, 0x34,
0xe1, 0x25, 0xf1, 0x17, 0x18, 0x19, 0x1a, 0x26,
0x27, 0x28, 0x29, 0x2a, 0x35, 0x36, 0x37, 0x38,
0x39, 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48,
0x49, 0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58,
0x59, 0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68,
0x69, 0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78,
0x79, 0x7a, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
0x88, 0x89, 0x8a, 0x92, 0x93, 0x94, 0x95, 0x96,
0x97, 0x98, 0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5,
0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4,
0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3,
0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2,
0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda,
0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9,
0xea, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8,
0xf9, 0xfa };
add_huff_table(cinfo, &cinfo->dc_huff_tbl_ptrs[0],
bits_dc_luminance, val_dc_luminance);
add_huff_table(cinfo, &cinfo->ac_huff_tbl_ptrs[0],
bits_ac_luminance, val_ac_luminance);
add_huff_table(cinfo, &cinfo->dc_huff_tbl_ptrs[1],
bits_dc_chrominance, val_dc_chrominance);
add_huff_table(cinfo, &cinfo->ac_huff_tbl_ptrs[1],
bits_ac_chrominance, val_ac_chrominance);
}
/*
* Default parameter setup for compression.
*
* Applications that don't choose to use this routine must do their
* own setup of all these parameters. Alternately, you can call this
* to establish defaults and then alter parameters selectively. This
* is the recommended approach since, if we add any new parameters,
* your code will still work (they'll be set to reasonable defaults).
*/
GLOBAL(void)
jpeg_set_defaults (j_compress_ptr cinfo)
{
int i;
/* Safety check to ensure start_compress not called yet. */
if (cinfo->global_state != CSTATE_START)
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
/* Allocate comp_info array large enough for maximum component count.
* Array is made permanent in case application wants to compress
* multiple images at same param settings.
*/
if (cinfo->comp_info == NULL)
cinfo->comp_info = (jpeg_component_info *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
MAX_COMPONENTS * SIZEOF(jpeg_component_info));
/* Initialize everything not dependent on the color space */
cinfo->data_precision = BITS_IN_JSAMPLE;
/* Set up two quantization tables using default quality of 75 */
jpeg_set_quality(cinfo, 75, TRUE);
/* Set up two Huffman tables */
std_huff_tables(cinfo);
/* Initialize default arithmetic coding conditioning */
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;
}
/* Default is no multiple-scan output */
cinfo->scan_info = NULL;
cinfo->num_scans = 0;
/* Expect normal source image, not raw downsampled data */
cinfo->raw_data_in = FALSE;
/* Use Huffman coding, not arithmetic coding, by default */
cinfo->arith_code = FALSE;
/* By default, don't do extra passes to optimize entropy coding */
cinfo->optimize_coding = FALSE;
/* The standard Huffman tables are only valid for 8-bit data precision.
* If the precision is higher, force optimization on so that usable
* tables will be computed. This test can be removed if default tables
* are supplied that are valid for the desired precision.
*/
if (cinfo->data_precision > 8)
cinfo->optimize_coding = TRUE;
/* By default, use the simpler non-cosited sampling alignment */
cinfo->CCIR601_sampling = FALSE;
/* No input smoothing */
cinfo->smoothing_factor = 0;
/* DCT algorithm preference */
cinfo->dct_method = JDCT_DEFAULT;
/* No restart markers */
cinfo->restart_interval = 0;
cinfo->restart_in_rows = 0;
/* Fill in default JFIF marker parameters. Note that whether the marker
* will actually be written is determined by jpeg_set_colorspace.
*
* By default, the library emits JFIF version code 1.01.
* An application that wants to emit JFIF 1.02 extension markers should set
* JFIF_minor_version to 2. We could probably get away with just defaulting
* to 1.02, but there may still be some decoders in use that will complain
* about that; saying 1.01 should minimize compatibility problems.
*/
cinfo->JFIF_major_version = 1; /* Default JFIF version = 1.01 */
cinfo->JFIF_minor_version = 1;
cinfo->density_unit = 0; /* Pixel size is unknown by default */
cinfo->X_density = 1; /* Pixel aspect ratio is square by default */
cinfo->Y_density = 1;
/* Choose JPEG colorspace based on input space, set defaults accordingly */
jpeg_default_colorspace(cinfo);
}
/*
* Select an appropriate JPEG colorspace for in_color_space.
*/
GLOBAL(void)
jpeg_default_colorspace (j_compress_ptr cinfo)
{
switch (cinfo->in_color_space) {
case JCS_GRAYSCALE:
jpeg_set_colorspace(cinfo, JCS_GRAYSCALE);
break;
case JCS_RGB:
jpeg_set_colorspace(cinfo, JCS_YCbCr);
break;
case JCS_YCbCr:
jpeg_set_colorspace(cinfo, JCS_YCbCr);
break;
case JCS_CMYK:
jpeg_set_colorspace(cinfo, JCS_CMYK); /* By default, no translation */
break;
case JCS_YCCK:
jpeg_set_colorspace(cinfo, JCS_YCCK);
break;
case JCS_UNKNOWN:
jpeg_set_colorspace(cinfo, JCS_UNKNOWN);
break;
default:
ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);
}
}
/*
* Set the JPEG colorspace, and choose colorspace-dependent default values.
*/
GLOBAL(void)
jpeg_set_colorspace (j_compress_ptr cinfo, J_COLOR_SPACE colorspace)
{
jpeg_component_info * compptr;
int ci;
#define SET_COMP(index,id,hsamp,vsamp,quant,dctbl,actbl) \
(compptr = &cinfo->comp_info[index], \
compptr->component_id = (id), \
compptr->h_samp_factor = (hsamp), \
compptr->v_samp_factor = (vsamp), \
compptr->quant_tbl_no = (quant), \
compptr->dc_tbl_no = (dctbl), \
compptr->ac_tbl_no = (actbl) )
/* Safety check to ensure start_compress not called yet. */
if (cinfo->global_state != CSTATE_START)
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
/* For all colorspaces, we use Q and Huff tables 0 for luminance components,
* tables 1 for chrominance components.
*/
cinfo->jpeg_color_space = colorspace;
cinfo->write_JFIF_header = FALSE; /* No marker for non-JFIF colorspaces */
cinfo->write_Adobe_marker = FALSE; /* write no Adobe marker by default */
switch (colorspace) {
case JCS_GRAYSCALE:
cinfo->write_JFIF_header = TRUE; /* Write a JFIF marker */
cinfo->num_components = 1;
/* JFIF specifies component ID 1 */
SET_COMP(0, 1, 1,1, 0, 0,0);
break;
case JCS_RGB:
cinfo->write_Adobe_marker = TRUE; /* write Adobe marker to flag RGB */
cinfo->num_components = 3;
SET_COMP(0, 0x52 /* 'R' */, 1,1, 0, 0,0);
SET_COMP(1, 0x47 /* 'G' */, 1,1, 0, 0,0);
SET_COMP(2, 0x42 /* 'B' */, 1,1, 0, 0,0);
break;
case JCS_YCbCr:
cinfo->write_JFIF_header = TRUE; /* Write a JFIF marker */
cinfo->num_components = 3;
/* JFIF specifies component IDs 1,2,3 */
/* We default to 2x2 subsamples of chrominance */
SET_COMP(0, 1, 2,2, 0, 0,0);
SET_COMP(1, 2, 1,1, 1, 1,1);
SET_COMP(2, 3, 1,1, 1, 1,1);
break;
case JCS_CMYK:
cinfo->write_Adobe_marker = TRUE; /* write Adobe marker to flag CMYK */
cinfo->num_components = 4;
SET_COMP(0, 0x43 /* 'C' */, 1,1, 0, 0,0);
SET_COMP(1, 0x4D /* 'M' */, 1,1, 0, 0,0);
SET_COMP(2, 0x59 /* 'Y' */, 1,1, 0, 0,0);
SET_COMP(3, 0x4B /* 'K' */, 1,1, 0, 0,0);
break;
case JCS_YCCK:
cinfo->write_Adobe_marker = TRUE; /* write Adobe marker to flag YCCK */
cinfo->num_components = 4;
SET_COMP(0, 1, 2,2, 0, 0,0);
SET_COMP(1, 2, 1,1, 1, 1,1);
SET_COMP(2, 3, 1,1, 1, 1,1);
SET_COMP(3, 4, 2,2, 0, 0,0);
break;
case JCS_UNKNOWN:
cinfo->num_components = cinfo->input_components;
if (cinfo->num_components < 1 || cinfo->num_components > MAX_COMPONENTS)
ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,
MAX_COMPONENTS);
for (ci = 0; ci < cinfo->num_components; ci++) {
SET_COMP(ci, ci, 1,1, 0, 0,0);
}
break;
default:
ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);
}
}
#ifdef C_PROGRESSIVE_SUPPORTED
LOCAL(jpeg_scan_info *)
fill_a_scan (jpeg_scan_info * scanptr, int ci,
int Ss, int Se, int Ah, int Al)
/* Support routine: generate one scan for specified component */
{
scanptr->comps_in_scan = 1;
scanptr->component_index[0] = ci;
scanptr->Ss = Ss;
scanptr->Se = Se;
scanptr->Ah = Ah;
scanptr->Al = Al;
scanptr++;
return scanptr;
}
LOCAL(jpeg_scan_info *)
fill_scans (jpeg_scan_info * scanptr, int ncomps,
int Ss, int Se, int Ah, int Al)
/* Support routine: generate one scan for each component */
{
int ci;
for (ci = 0; ci < ncomps; ci++) {
scanptr->comps_in_scan = 1;
scanptr->component_index[0] = ci;
scanptr->Ss = Ss;
scanptr->Se = Se;
scanptr->Ah = Ah;
scanptr->Al = Al;
scanptr++;
}
return scanptr;
}
LOCAL(jpeg_scan_info *)
fill_dc_scans (jpeg_scan_info * scanptr, int ncomps, int Ah, int Al)
/* Support routine: generate interleaved DC scan if possible, else N scans */
{
int ci;
if (ncomps <= MAX_COMPS_IN_SCAN) {
/* Single interleaved DC scan */
scanptr->comps_in_scan = ncomps;
for (ci = 0; ci < ncomps; ci++)
scanptr->component_index[ci] = ci;
scanptr->Ss = scanptr->Se = 0;
scanptr->Ah = Ah;
scanptr->Al = Al;
scanptr++;
} else {
/* Noninterleaved DC scan for each component */
scanptr = fill_scans(scanptr, ncomps, 0, 0, Ah, Al);
}
return scanptr;
}
/*
* Create a recommended progressive-JPEG script.
* cinfo->num_components and cinfo->jpeg_color_space must be correct.
*/
GLOBAL(void)
jpeg_simple_progression (j_compress_ptr cinfo)
{
int ncomps = cinfo->num_components;
int nscans;
jpeg_scan_info * scanptr;
/* Safety check to ensure start_compress not called yet. */
if (cinfo->global_state != CSTATE_START)
ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
/* Figure space needed for script. Calculation must match code below! */
if (ncomps == 3 && cinfo->jpeg_color_space == JCS_YCbCr) {
/* Custom script for YCbCr color images. */
nscans = 10;
} else {
/* All-purpose script for other color spaces. */
if (ncomps > MAX_COMPS_IN_SCAN)
nscans = 6 * ncomps; /* 2 DC + 4 AC scans per component */
else
nscans = 2 + 4 * ncomps; /* 2 DC scans; 4 AC scans per component */
}
/* Allocate space for script.
* We need to put it in the permanent pool in case the application performs
* multiple compressions without changing the settings. To avoid a memory
* leak if jpeg_simple_progression is called repeatedly for the same JPEG
* object, we try to re-use previously allocated space, and we allocate
* enough space to handle YCbCr even if initially asked for grayscale.
*/
if (cinfo->script_space == NULL || cinfo->script_space_size < nscans) {
cinfo->script_space_size = MAX(nscans, 10);
cinfo->script_space = (jpeg_scan_info *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
cinfo->script_space_size * SIZEOF(jpeg_scan_info));
}
scanptr = cinfo->script_space;
cinfo->scan_info = scanptr;
cinfo->num_scans = nscans;
if (ncomps == 3 && cinfo->jpeg_color_space == JCS_YCbCr) {
/* Custom script for YCbCr color images. */
/* Initial DC scan */
scanptr = fill_dc_scans(scanptr, ncomps, 0, 1);
/* Initial AC scan: get some luma data out in a hurry */
scanptr = fill_a_scan(scanptr, 0, 1, 5, 0, 2);
/* Chroma data is too small to be worth expending many scans on */
scanptr = fill_a_scan(scanptr, 2, 1, 63, 0, 1);
scanptr = fill_a_scan(scanptr, 1, 1, 63, 0, 1);
/* Complete spectral selection for luma AC */
scanptr = fill_a_scan(scanptr, 0, 6, 63, 0, 2);
/* Refine next bit of luma AC */
scanptr = fill_a_scan(scanptr, 0, 1, 63, 2, 1);
/* Finish DC successive approximation */
scanptr = fill_dc_scans(scanptr, ncomps, 1, 0);
/* Finish AC successive approximation */
scanptr = fill_a_scan(scanptr, 2, 1, 63, 1, 0);
scanptr = fill_a_scan(scanptr, 1, 1, 63, 1, 0);
/* Luma bottom bit comes last since it's usually largest scan */
scanptr = fill_a_scan(scanptr, 0, 1, 63, 1, 0);
} else {
/* All-purpose script for other color spaces. */
/* Successive approximation first pass */
scanptr = fill_dc_scans(scanptr, ncomps, 0, 1);
scanptr = fill_scans(scanptr, ncomps, 1, 5, 0, 2);
scanptr = fill_scans(scanptr, ncomps, 6, 63, 0, 2);
/* Successive approximation second pass */
scanptr = fill_scans(scanptr, ncomps, 1, 63, 2, 1);
/* Successive approximation final pass */
scanptr = fill_dc_scans(scanptr, ncomps, 1, 0);
scanptr = fill_scans(scanptr, ncomps, 1, 63, 1, 0);
}
}
#endif /* C_PROGRESSIVE_SUPPORTED */
dlib/external/libjpeg/jcphuff.cpp 0 → 100644
View file @ 747088ea
/*
* jcphuff.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 encoding routines for progressive JPEG.
*
* We do not support output suspension in this module, since the library
* currently does not allow multiple-scan files to be written with output
* suspension.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
#include "jchuff.h" /* Declarations shared with jchuff.c */
#ifdef C_PROGRESSIVE_SUPPORTED
/* Expanded entropy encoder object for progressive Huffman encoding. */
typedef struct {
struct jpeg_entropy_encoder pub; /* public fields */
/* Mode flag: TRUE for optimization, FALSE for actual data output */
int gather_statistics;
/* Bit-level coding status.
* next_output_byte/free_in_buffer are local copies of cinfo->dest fields.
*/
JOCTET * next_output_byte; /* => next byte to write in buffer */
size_t free_in_buffer; /* # of byte spaces remaining in buffer */
long put_buffer; /* current bit-accumulation buffer */
int put_bits; /* # of bits now in it */
j_compress_ptr cinfo; /* link to cinfo (needed for dump_buffer) */
/* Coding status for DC components */
int last_dc_val[MAX_COMPS_IN_SCAN]; /* last DC coef for each component */
/* Coding status for AC components */
int ac_tbl_no; /* the table number of the single component */
unsigned int EOBRUN; /* run length of EOBs */
unsigned int BE; /* # of buffered correction bits before MCU */
char * bit_buffer; /* buffer for correction bits (1 per char) */
/* packing correction bits tightly would save some space but cost time... */
unsigned int restarts_to_go; /* MCUs left in this restart interval */
int next_restart_num; /* next restart number to write (0-7) */
/* Pointers to derived tables (these workspaces have image lifespan).
* Since any one scan codes only DC or only AC, we only need one set
* of tables, not one for DC and one for AC.
*/
c_derived_tbl * derived_tbls[NUM_HUFF_TBLS];
/* Statistics tables for optimization; again, one set is enough */
long * count_ptrs[NUM_HUFF_TBLS];
} phuff_entropy_encoder;
typedef phuff_entropy_encoder * phuff_entropy_ptr;
/* MAX_CORR_BITS is the number of bits the AC refinement correction-bit
* buffer can hold. Larger sizes may slightly improve compression, but
* 1000 is already well into the realm of overkill.
* The minimum safe size is 64 bits.
*/
#define MAX_CORR_BITS 1000 /* Max # of correction bits I can buffer */
/* IRIGHT_SHIFT is like RIGHT_SHIFT, but works on int rather than long.
* We assume that int right shift is unsigned if long right shift is,
* which should be safe.
*/
#ifdef RIGHT_SHIFT_IS_UNSIGNED
#define ISHIFT_TEMPS int ishift_temp;
#define IRIGHT_SHIFT(x,shft) \
((ishift_temp = (x)) < 0 ? \
(ishift_temp >> (shft)) | ((~0) << (16-(shft))) : \
(ishift_temp >> (shft)))
#else
#define ISHIFT_TEMPS
#define IRIGHT_SHIFT(x,shft) ((x) >> (shft))
#endif
/* Forward declarations */
METHODDEF(int) encode_mcu_DC_first JPP((j_compress_ptr cinfo,
JBLOCKROW *MCU_data));
METHODDEF(int) encode_mcu_AC_first JPP((j_compress_ptr cinfo,
JBLOCKROW *MCU_data));
METHODDEF(int) encode_mcu_DC_refine JPP((j_compress_ptr cinfo,
JBLOCKROW *MCU_data));
METHODDEF(int) encode_mcu_AC_refine JPP((j_compress_ptr cinfo,
JBLOCKROW *MCU_data));
METHODDEF(void) finish_pass_phuff JPP((j_compress_ptr cinfo));
METHODDEF(void) finish_pass_gather_phuff JPP((j_compress_ptr cinfo));
/*
* Initialize for a Huffman-compressed scan using progressive JPEG.
*/
METHODDEF(void)
start_pass_phuff (j_compress_ptr cinfo, int gather_statistics)
{
phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
int is_DC_band;
int ci, tbl;
jpeg_component_info * compptr;
entropy->cinfo = cinfo;
entropy->gather_statistics = gather_statistics;
is_DC_band = (cinfo->Ss == 0);
/* We assume jcmaster.c already validated the scan parameters. */
/* Select execution routines */
if (cinfo->Ah == 0) {
if (is_DC_band)
entropy->pub.encode_mcu = encode_mcu_DC_first;
else
entropy->pub.encode_mcu = encode_mcu_AC_first;
} else {
if (is_DC_band)
entropy->pub.encode_mcu = encode_mcu_DC_refine;
else {
entropy->pub.encode_mcu = encode_mcu_AC_refine;
/* AC refinement needs a correction bit buffer */
if (entropy->bit_buffer == NULL)
entropy->bit_buffer = (char *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
MAX_CORR_BITS * SIZEOF(char));
}
}
if (gather_statistics)
entropy->pub.finish_pass = finish_pass_gather_phuff;
else
entropy->pub.finish_pass = finish_pass_phuff;
/* Only DC coefficients may be interleaved, so cinfo->comps_in_scan = 1
* for AC coefficients.
*/
for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
compptr = cinfo->cur_comp_info[ci];
/* Initialize DC predictions to 0 */
entropy->last_dc_val[ci] = 0;
/* Get table index */
if (is_DC_band) {
if (cinfo->Ah != 0) /* DC refinement needs no table */
continue;
tbl = compptr->dc_tbl_no;
} else {
entropy->ac_tbl_no = tbl = compptr->ac_tbl_no;
}
if (gather_statistics) {
/* Check for invalid table index */
/* (make_c_derived_tbl does this in the other path) */
if (tbl < 0 || tbl >= NUM_HUFF_TBLS)
ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, tbl);
/* Allocate and zero the statistics tables */
/* Note that jpeg_gen_optimal_table expects 257 entries in each table! */
if (entropy->count_ptrs[tbl] == NULL)
entropy->count_ptrs[tbl] = (long *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
257 * SIZEOF(long));
MEMZERO(entropy->count_ptrs[tbl], 257 * SIZEOF(long));
} else {
/* Compute derived values for Huffman table */
/* We may do this more than once for a table, but it's not expensive */
jpeg_make_c_derived_tbl(cinfo, is_DC_band, tbl,
& entropy->derived_tbls[tbl]);
}
}
/* Initialize AC stuff */
entropy->EOBRUN = 0;
entropy->BE = 0;
/* Initialize bit buffer to empty */
entropy->put_buffer = 0;
entropy->put_bits = 0;
/* Initialize restart stuff */
entropy->restarts_to_go = cinfo->restart_interval;
entropy->next_restart_num = 0;
}
/* Outputting bytes to the file.
* NB: these must be called only when actually outputting,
* that is, entropy->gather_statistics == FALSE.
*/
/* Emit a byte */
#define emit_byte(entropy,val) \
{ *(entropy)->next_output_byte++ = (JOCTET) (val); \
if (--(entropy)->free_in_buffer == 0) \
dump_buffer(entropy); }
LOCAL(void)
dump_buffer (phuff_entropy_ptr entropy)
/* Empty the output buffer; we do not support suspension in this module. */
{
struct jpeg_destination_mgr * dest = entropy->cinfo->dest;
if (! (*dest->empty_output_buffer) (entropy->cinfo))
ERREXIT(entropy->cinfo, JERR_CANT_SUSPEND);
/* After a successful buffer dump, must reset buffer pointers */
entropy->next_output_byte = dest->next_output_byte;
entropy->free_in_buffer = dest->free_in_buffer;
}
/* Outputting bits to the file */
/* Only the right 24 bits of put_buffer are used; the valid bits are
* left-justified in this part. At most 16 bits can be passed to emit_bits
* in one call, and we never retain more than 7 bits in put_buffer
* between calls, so 24 bits are sufficient.
*/
INLINE
LOCAL(void)
emit_bits (phuff_entropy_ptr entropy, unsigned int code, int size)
/* Emit some bits, unless we are in gather mode */
{
/* This routine is heavily used, so it's worth coding tightly. */
register long put_buffer = (long) code;
register int put_bits = entropy->put_bits;
/* if size is 0, caller used an invalid Huffman table entry */
if (size == 0)
ERREXIT(entropy->cinfo, JERR_HUFF_MISSING_CODE);
if (entropy->gather_statistics)
return; /* do nothing if we're only getting stats */
put_buffer &= (((long) 1)<<size) - 1; /* mask off any extra bits in code */
put_bits += size; /* new number of bits in buffer */
put_buffer <<= 24 - put_bits; /* align incoming bits */
put_buffer |= entropy->put_buffer; /* and merge with old buffer contents */
while (put_bits >= 8) {
int c = (int) ((put_buffer >> 16) & 0xFF);
emit_byte(entropy, c);
if (c == 0xFF) { /* need to stuff a zero byte? */
emit_byte(entropy, 0);
}
put_buffer <<= 8;
put_bits -= 8;
}
entropy->put_buffer = put_buffer; /* update variables */
entropy->put_bits = put_bits;
}
LOCAL(void)
flush_bits (phuff_entropy_ptr entropy)
{
emit_bits(entropy, 0x7F, 7); /* fill any partial byte with ones */
entropy->put_buffer = 0; /* and reset bit-buffer to empty */
entropy->put_bits = 0;
}
/*
* Emit (or just count) a Huffman symbol.
*/
INLINE
LOCAL(void)
emit_symbol (phuff_entropy_ptr entropy, int tbl_no, int symbol)
{
if (entropy->gather_statistics)
entropy->count_ptrs[tbl_no][symbol]++;
else {
c_derived_tbl * tbl = entropy->derived_tbls[tbl_no];
emit_bits(entropy, tbl->ehufco[symbol], tbl->ehufsi[symbol]);
}
}
/*
* Emit bits from a correction bit buffer.
*/
LOCAL(void)
emit_buffered_bits (phuff_entropy_ptr entropy, char * bufstart,
unsigned int nbits)
{
if (entropy->gather_statistics)
return; /* no real work */
while (nbits > 0) {
emit_bits(entropy, (unsigned int) (*bufstart), 1);
bufstart++;
nbits--;
}
}
/*
* Emit any pending EOBRUN symbol.
*/
LOCAL(void)
emit_eobrun (phuff_entropy_ptr entropy)
{
register int temp, nbits;
if (entropy->EOBRUN > 0) { /* if there is any pending EOBRUN */
temp = entropy->EOBRUN;
nbits = 0;
while ((temp >>= 1))
nbits++;
/* safety check: shouldn't happen given limited correction-bit buffer */
if (nbits > 14)
ERREXIT(entropy->cinfo, JERR_HUFF_MISSING_CODE);
emit_symbol(entropy, entropy->ac_tbl_no, nbits << 4);
if (nbits)
emit_bits(entropy, entropy->EOBRUN, nbits);
entropy->EOBRUN = 0;
/* Emit any buffered correction bits */
emit_buffered_bits(entropy, entropy->bit_buffer, entropy->BE);
entropy->BE = 0;
}
}
/*
* Emit a restart marker & resynchronize predictions.
*/
LOCAL(void)
emit_restart (phuff_entropy_ptr entropy, int restart_num)
{
int ci;
emit_eobrun(entropy);
if (! entropy->gather_statistics) {
flush_bits(entropy);
emit_byte(entropy, 0xFF);
emit_byte(entropy, JPEG_RST0 + restart_num);
}
if (entropy->cinfo->Ss == 0) {
/* Re-initialize DC predictions to 0 */
for (ci = 0; ci < entropy->cinfo->comps_in_scan; ci++)
entropy->last_dc_val[ci] = 0;
} else {
/* Re-initialize all AC-related fields to 0 */
entropy->EOBRUN = 0;
entropy->BE = 0;
}
}
/*
* MCU encoding for DC initial scan (either spectral selection,
* or first pass of successive approximation).
*/
METHODDEF(int)
encode_mcu_DC_first (j_compress_ptr cinfo, JBLOCKROW *MCU_data)
{
phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
register int temp, temp2;
register int nbits;
int blkn, ci;
int Al = cinfo->Al;
JBLOCKROW block;
jpeg_component_info * compptr;
ISHIFT_TEMPS
entropy->next_output_byte = cinfo->dest->next_output_byte;
entropy->free_in_buffer = cinfo->dest->free_in_buffer;
/* Emit restart marker if needed */
if (cinfo->restart_interval)
if (entropy->restarts_to_go == 0)
emit_restart(entropy, entropy->next_restart_num);
/* Encode the MCU data blocks */
for (blkn = 0; blkn < cinfo->blocks_in_MCU; blkn++) {
block = MCU_data[blkn];
ci = cinfo->MCU_membership[blkn];
compptr = cinfo->cur_comp_info[ci];
/* Compute the DC value after the required point transform by Al.
* This is simply an arithmetic right shift.
*/
temp2 = IRIGHT_SHIFT((int) ((*block)[0]), Al);
/* DC differences are figured on the point-transformed values. */
temp = temp2 - entropy->last_dc_val[ci];
entropy->last_dc_val[ci] = temp2;
/* Encode the DC coefficient difference per section G.1.2.1 */
temp2 = temp;
if (temp < 0) {
temp = -temp; /* temp is abs value of input */
/* For a negative input, want temp2 = bitwise complement of abs(input) */
/* This code assumes we are on a two's complement machine */
temp2--;
}
/* Find the number of bits needed for the magnitude of the coefficient */
nbits = 0;
while (temp) {
nbits++;
temp >>= 1;
}
/* Check for out-of-range coefficient values.
* Since we're encoding a difference, the range limit is twice as much.
*/
if (nbits > MAX_COEF_BITS+1)
ERREXIT(cinfo, JERR_BAD_DCT_COEF);
/* Count/emit the Huffman-coded symbol for the number of bits */
emit_symbol(entropy, compptr->dc_tbl_no, nbits);
/* Emit that number of bits of the value, if positive, */
/* or the complement of its magnitude, if negative. */
if (nbits) /* emit_bits rejects calls with size 0 */
emit_bits(entropy, (unsigned int) temp2, nbits);
}
cinfo->dest->next_output_byte = entropy->next_output_byte;
cinfo->dest->free_in_buffer = entropy->free_in_buffer;
/* Update restart-interval state too */
if (cinfo->restart_interval) {
if (entropy->restarts_to_go == 0) {
entropy->restarts_to_go = cinfo->restart_interval;
entropy->next_restart_num++;
entropy->next_restart_num &= 7;
}
entropy->restarts_to_go--;
}
return TRUE;
}
/*
* MCU encoding for AC initial scan (either spectral selection,
* or first pass of successive approximation).
*/
METHODDEF(int)
encode_mcu_AC_first (j_compress_ptr cinfo, JBLOCKROW *MCU_data)
{
phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
register int temp, temp2;
register int nbits;
register int r, k;
int Se = cinfo->Se;
int Al = cinfo->Al;
JBLOCKROW block;
entropy->next_output_byte = cinfo->dest->next_output_byte;
entropy->free_in_buffer = cinfo->dest->free_in_buffer;
/* Emit restart marker if needed */
if (cinfo->restart_interval)
if (entropy->restarts_to_go == 0)
emit_restart(entropy, entropy->next_restart_num);
/* Encode the MCU data block */
block = MCU_data[0];
/* Encode the AC coefficients per section G.1.2.2, fig. G.3 */
r = 0; /* r = run length of zeros */
for (k = cinfo->Ss; k <= Se; k++) {
if ((temp = (*block)[jpeg_natural_order[k]]) == 0) {
r++;
continue;
}
/* We must apply the point transform by Al. For AC coefficients this
* is an integer division with rounding towards 0. To do this portably
* in C, we shift after obtaining the absolute value; so the code is
* interwoven with finding the abs value (temp) and output bits (temp2).
*/
if (temp < 0) {
temp = -temp; /* temp is abs value of input */
temp >>= Al; /* apply the point transform */
/* For a negative coef, want temp2 = bitwise complement of abs(coef) */
temp2 = ~temp;
} else {
temp >>= Al; /* apply the point transform */
temp2 = temp;
}
/* Watch out for case that nonzero coef is zero after point transform */
if (temp == 0) {
r++;
continue;
}
/* Emit any pending EOBRUN */
if (entropy->EOBRUN > 0)
emit_eobrun(entropy);
/* if run length > 15, must emit special run-length-16 codes (0xF0) */
while (r > 15) {
emit_symbol(entropy, entropy->ac_tbl_no, 0xF0);
r -= 16;
}
/* Find the number of bits needed for the magnitude of the coefficient */
nbits = 1; /* there must be at least one 1 bit */
while ((temp >>= 1))
nbits++;
/* Check for out-of-range coefficient values */
if (nbits > MAX_COEF_BITS)
ERREXIT(cinfo, JERR_BAD_DCT_COEF);
/* Count/emit Huffman symbol for run length / number of bits */
emit_symbol(entropy, entropy->ac_tbl_no, (r << 4) + nbits);
/* Emit that number of bits of the value, if positive, */
/* or the complement of its magnitude, if negative. */
emit_bits(entropy, (unsigned int) temp2, nbits);
r = 0; /* reset zero run length */
}
if (r > 0) { /* If there are trailing zeroes, */
entropy->EOBRUN++; /* count an EOB */
if (entropy->EOBRUN == 0x7FFF)
emit_eobrun(entropy); /* force it out to avoid overflow */
}
cinfo->dest->next_output_byte = entropy->next_output_byte;
cinfo->dest->free_in_buffer = entropy->free_in_buffer;
/* Update restart-interval state too */
if (cinfo->restart_interval) {
if (entropy->restarts_to_go == 0) {
entropy->restarts_to_go = cinfo->restart_interval;
entropy->next_restart_num++;
entropy->next_restart_num &= 7;
}
entropy->restarts_to_go--;
}
return TRUE;
}
/*
* MCU encoding 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(int)
encode_mcu_DC_refine (j_compress_ptr cinfo, JBLOCKROW *MCU_data)
{
phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
register int temp;
int blkn;
int Al = cinfo->Al;
JBLOCKROW block;
entropy->next_output_byte = cinfo->dest->next_output_byte;
entropy->free_in_buffer = cinfo->dest->free_in_buffer;
/* Emit restart marker if needed */
if (cinfo->restart_interval)
if (entropy->restarts_to_go == 0)
emit_restart(entropy, entropy->next_restart_num);
/* Encode the MCU data blocks */
for (blkn = 0; blkn < cinfo->blocks_in_MCU; blkn++) {
block = MCU_data[blkn];
/* We simply emit the Al'th bit of the DC coefficient value. */
temp = (*block)[0];
emit_bits(entropy, (unsigned int) (temp >> Al), 1);
}
cinfo->dest->next_output_byte = entropy->next_output_byte;
cinfo->dest->free_in_buffer = entropy->free_in_buffer;
/* Update restart-interval state too */
if (cinfo->restart_interval) {
if (entropy->restarts_to_go == 0) {
entropy->restarts_to_go = cinfo->restart_interval;
entropy->next_restart_num++;
entropy->next_restart_num &= 7;
}
entropy->restarts_to_go--;
}
return TRUE;
}
/*
* MCU encoding for AC successive approximation refinement scan.
*/
METHODDEF(int)
encode_mcu_AC_refine (j_compress_ptr cinfo, JBLOCKROW *MCU_data)
{
phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
register int temp;
register int r, k;
int EOB;
char *BR_buffer;
unsigned int BR;
int Se = cinfo->Se;
int Al = cinfo->Al;
JBLOCKROW block;
int absvalues[DCTSIZE2];
entropy->next_output_byte = cinfo->dest->next_output_byte;
entropy->free_in_buffer = cinfo->dest->free_in_buffer;
/* Emit restart marker if needed */
if (cinfo->restart_interval)
if (entropy->restarts_to_go == 0)
emit_restart(entropy, entropy->next_restart_num);
/* Encode the MCU data block */
block = MCU_data[0];
/* It is convenient to make a pre-pass to determine the transformed
* coefficients' absolute values and the EOB position.
*/
EOB = 0;
for (k = cinfo->Ss; k <= Se; k++) {
temp = (*block)[jpeg_natural_order[k]];
/* We must apply the point transform by Al. For AC coefficients this
* is an integer division with rounding towards 0. To do this portably
* in C, we shift after obtaining the absolute value.
*/
if (temp < 0)
temp = -temp; /* temp is abs value of input */
temp >>= Al; /* apply the point transform */
absvalues[k] = temp; /* save abs value for main pass */
if (temp == 1)
EOB = k; /* EOB = index of last newly-nonzero coef */
}
/* Encode the AC coefficients per section G.1.2.3, fig. G.7 */
r = 0; /* r = run length of zeros */
BR = 0; /* BR = count of buffered bits added now */
BR_buffer = entropy->bit_buffer + entropy->BE; /* Append bits to buffer */
for (k = cinfo->Ss; k <= Se; k++) {
if ((temp = absvalues[k]) == 0) {
r++;
continue;
}
/* Emit any required ZRLs, but not if they can be folded into EOB */
while (r > 15 && k <= EOB) {
/* emit any pending EOBRUN and the BE correction bits */
emit_eobrun(entropy);
/* Emit ZRL */
emit_symbol(entropy, entropy->ac_tbl_no, 0xF0);
r -= 16;
/* Emit buffered correction bits that must be associated with ZRL */
emit_buffered_bits(entropy, BR_buffer, BR);
BR_buffer = entropy->bit_buffer; /* BE bits are gone now */
BR = 0;
}
/* If the coef was previously nonzero, it only needs a correction bit.
* NOTE: a straight translation of the spec's figure G.7 would suggest
* that we also need to test r > 15. But if r > 15, we can only get here
* if k > EOB, which implies that this coefficient is not 1.
*/
if (temp > 1) {
/* The correction bit is the next bit of the absolute value. */
BR_buffer[BR++] = (char) (temp & 1);
continue;
}
/* Emit any pending EOBRUN and the BE correction bits */
emit_eobrun(entropy);
/* Count/emit Huffman symbol for run length / number of bits */
emit_symbol(entropy, entropy->ac_tbl_no, (r << 4) + 1);
/* Emit output bit for newly-nonzero coef */
temp = ((*block)[jpeg_natural_order[k]] < 0) ? 0 : 1;
emit_bits(entropy, (unsigned int) temp, 1);
/* Emit buffered correction bits that must be associated with this code */
emit_buffered_bits(entropy, BR_buffer, BR);
BR_buffer = entropy->bit_buffer; /* BE bits are gone now */
BR = 0;
r = 0; /* reset zero run length */
}
if (r > 0 || BR > 0) { /* If there are trailing zeroes, */
entropy->EOBRUN++; /* count an EOB */
entropy->BE += BR; /* concat my correction bits to older ones */
/* We force out the EOB if we risk either:
* 1. overflow of the EOB counter;
* 2. overflow of the correction bit buffer during the next MCU.
*/
if (entropy->EOBRUN == 0x7FFF || entropy->BE > (MAX_CORR_BITS-DCTSIZE2+1))
emit_eobrun(entropy);
}
cinfo->dest->next_output_byte = entropy->next_output_byte;
cinfo->dest->free_in_buffer = entropy->free_in_buffer;
/* Update restart-interval state too */
if (cinfo->restart_interval) {
if (entropy->restarts_to_go == 0) {
entropy->restarts_to_go = cinfo->restart_interval;
entropy->next_restart_num++;
entropy->next_restart_num &= 7;
}
entropy->restarts_to_go--;
}
return TRUE;
}
/*
* Finish up at the end of a Huffman-compressed progressive scan.
*/
METHODDEF(void)
finish_pass_phuff (j_compress_ptr cinfo)
{
phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
entropy->next_output_byte = cinfo->dest->next_output_byte;
entropy->free_in_buffer = cinfo->dest->free_in_buffer;
/* Flush out any buffered data */
emit_eobrun(entropy);
flush_bits(entropy);
cinfo->dest->next_output_byte = entropy->next_output_byte;
cinfo->dest->free_in_buffer = entropy->free_in_buffer;
}
/*
* Finish up a statistics-gathering pass and create the new Huffman tables.
*/
METHODDEF(void)
finish_pass_gather_phuff (j_compress_ptr cinfo)
{
phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;
int is_DC_band;
int ci, tbl;
jpeg_component_info * compptr;
JHUFF_TBL **htblptr;
int did[NUM_HUFF_TBLS];
/* Flush out buffered data (all we care about is counting the EOB symbol) */
emit_eobrun(entropy);
is_DC_band = (cinfo->Ss == 0);
/* It's important not to apply jpeg_gen_optimal_table more than once
* per table, because it clobbers the input frequency counts!
*/
MEMZERO(did, SIZEOF(did));
for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
compptr = cinfo->cur_comp_info[ci];
if (is_DC_band) {
if (cinfo->Ah != 0) /* DC refinement needs no table */
continue;
tbl = compptr->dc_tbl_no;
} else {
tbl = compptr->ac_tbl_no;
}
if (! did[tbl]) {
if (is_DC_band)
htblptr = & cinfo->dc_huff_tbl_ptrs[tbl];
else
htblptr = & cinfo->ac_huff_tbl_ptrs[tbl];
if (*htblptr == NULL)
*htblptr = jpeg_alloc_huff_table((j_common_ptr) cinfo);
jpeg_gen_optimal_table(cinfo, *htblptr, entropy->count_ptrs[tbl]);
did[tbl] = TRUE;
}
}
}
/*
* Module initialization routine for progressive Huffman entropy encoding.
*/
GLOBAL(void)
jinit_phuff_encoder (j_compress_ptr cinfo)
{
phuff_entropy_ptr entropy;
int i;
entropy = (phuff_entropy_ptr)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
SIZEOF(phuff_entropy_encoder));
cinfo->entropy = (struct jpeg_entropy_encoder *) entropy;
entropy->pub.start_pass = start_pass_phuff;
/* Mark tables unallocated */
for (i = 0; i < NUM_HUFF_TBLS; i++) {
entropy->derived_tbls[i] = NULL;
entropy->count_ptrs[i] = NULL;
}
entropy->bit_buffer = NULL; /* needed only in AC refinement scan */
}
#endif /* C_PROGRESSIVE_SUPPORTED */
dlib/external/libjpeg/jcprepct.cpp 0 → 100644
View file @ 747088ea
/*
* jcprepct.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 compression preprocessing controller.
* This controller manages the color conversion, downsampling,
* and edge expansion steps.
*
* Most of the complexity here is associated with buffering input rows
* as required by the downsampler. See the comments at the head of
* jcsample.c for the downsampler's needs.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
/* At present, jcsample.c can request context rows only for smoothing.
* In the future, we might also need context rows for CCIR601 sampling
* or other more-complex downsampling procedures. The code to support
* context rows should be compiled only if needed.
*/
#ifdef INPUT_SMOOTHING_SUPPORTED
#define CONTEXT_ROWS_SUPPORTED
#endif
/*
* For the simple (no-context-row) case, we just need to buffer one
* row group's worth of pixels for the downsampling step. At the bottom of
* the image, we pad to a full row group by replicating the last pixel row.
* The downsampler's last output row is then replicated if needed to pad
* out to a full iMCU row.
*
* When providing context rows, we must buffer three row groups' worth of
* pixels. Three row groups are physically allocated, but the row pointer
* arrays are made five row groups high, with the extra pointers above and
* below "wrapping around" to point to the last and first real row groups.
* This allows the downsampler to access the proper context rows.
* At the top and bottom of the image, we create dummy context rows by
* copying the first or last real pixel row. This copying could be avoided
* by pointer hacking as is done in jdmainct.c, but it doesn't seem worth the
* trouble on the compression side.
*/
/* Private buffer controller object */
typedef struct {
struct jpeg_c_prep_controller pub; /* public fields */
/* Downsampling input buffer. This buffer holds color-converted data
* until we have enough to do a downsample step.
*/
JSAMPARRAY color_buf[MAX_COMPONENTS];
JDIMENSION rows_to_go; /* counts rows remaining in source image */
int next_buf_row; /* index of next row to store in color_buf */
#ifdef CONTEXT_ROWS_SUPPORTED /* only needed for context case */
int this_row_group; /* starting row index of group to process */
int next_buf_stop; /* downsample when we reach this index */
#endif
} my_prep_controller;
typedef my_prep_controller * my_prep_ptr;
/*
* Initialize for a processing pass.
*/
METHODDEF(void)
start_pass_prep (j_compress_ptr cinfo, J_BUF_MODE pass_mode)
{
my_prep_ptr prep = (my_prep_ptr) cinfo->prep;
if (pass_mode != JBUF_PASS_THRU)
ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
/* Initialize total-height counter for detecting bottom of image */
prep->rows_to_go = cinfo->image_height;
/* Mark the conversion buffer empty */
prep->next_buf_row = 0;
#ifdef CONTEXT_ROWS_SUPPORTED
/* Preset additional state variables for context mode.
* These aren't used in non-context mode, so we needn't test which mode.
*/
prep->this_row_group = 0;
/* Set next_buf_stop to stop after two row groups have been read in. */
prep->next_buf_stop = 2 * cinfo->max_v_samp_factor;
#endif
}
/*
* Expand an image vertically from height input_rows to height output_rows,
* by duplicating the bottom row.
*/
LOCAL(void)
expand_bottom_edge (JSAMPARRAY image_data, JDIMENSION num_cols,
int input_rows, int output_rows)
{
register int row;
for (row = input_rows; row < output_rows; row++) {
jcopy_sample_rows(image_data, input_rows-1, image_data, row,
1, num_cols);
}
}
/*
* Process some data in the simple no-context case.
*
* Preprocessor output data is counted in "row groups". A row group
* is defined to be v_samp_factor sample rows of each component.
* Downsampling will produce this much data from each max_v_samp_factor
* input rows.
*/
METHODDEF(void)
pre_process_data (j_compress_ptr cinfo,
JSAMPARRAY input_buf, JDIMENSION *in_row_ctr,
JDIMENSION in_rows_avail,
JSAMPIMAGE output_buf, JDIMENSION *out_row_group_ctr,
JDIMENSION out_row_groups_avail)
{
my_prep_ptr prep = (my_prep_ptr) cinfo->prep;
int numrows, ci;
JDIMENSION inrows;
jpeg_component_info * compptr;
while (*in_row_ctr < in_rows_avail &&
*out_row_group_ctr < out_row_groups_avail) {
/* Do color conversion to fill the conversion buffer. */
inrows = in_rows_avail - *in_row_ctr;
numrows = cinfo->max_v_samp_factor - prep->next_buf_row;
numrows = (int) MIN((JDIMENSION) numrows, inrows);
(*cinfo->cconvert->color_convert) (cinfo, input_buf + *in_row_ctr,
prep->color_buf,
(JDIMENSION) prep->next_buf_row,
numrows);
*in_row_ctr += numrows;
prep->next_buf_row += numrows;
prep->rows_to_go -= numrows;
/* If at bottom of image, pad to fill the conversion buffer. */
if (prep->rows_to_go == 0 &&
prep->next_buf_row < cinfo->max_v_samp_factor) {
for (ci = 0; ci < cinfo->num_components; ci++) {
expand_bottom_edge(prep->color_buf[ci], cinfo->image_width,
prep->next_buf_row, cinfo->max_v_samp_factor);
}
prep->next_buf_row = cinfo->max_v_samp_factor;
}
/* If we've filled the conversion buffer, empty it. */
if (prep->next_buf_row == cinfo->max_v_samp_factor) {
(*cinfo->downsample->downsample) (cinfo,
prep->color_buf, (JDIMENSION) 0,
output_buf, *out_row_group_ctr);
prep->next_buf_row = 0;
(*out_row_group_ctr)++;
}
/* If at bottom of image, pad the output to a full iMCU height.
* Note we assume the caller is providing a one-iMCU-height output buffer!
*/
if (prep->rows_to_go == 0 &&
*out_row_group_ctr < out_row_groups_avail) {
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
expand_bottom_edge(output_buf[ci],
compptr->width_in_blocks * DCTSIZE,
(int) (*out_row_group_ctr * compptr->v_samp_factor),
(int) (out_row_groups_avail * compptr->v_samp_factor));
}
*out_row_group_ctr = out_row_groups_avail;
break; /* can exit outer loop without test */
}
}
}
#ifdef CONTEXT_ROWS_SUPPORTED
/*
* Process some data in the context case.
*/
METHODDEF(void)
pre_process_context (j_compress_ptr cinfo,
JSAMPARRAY input_buf, JDIMENSION *in_row_ctr,
JDIMENSION in_rows_avail,
JSAMPIMAGE output_buf, JDIMENSION *out_row_group_ctr,
JDIMENSION out_row_groups_avail)
{
my_prep_ptr prep = (my_prep_ptr) cinfo->prep;
int numrows, ci;
int buf_height = cinfo->max_v_samp_factor * 3;
JDIMENSION inrows;
while (*out_row_group_ctr < out_row_groups_avail) {
if (*in_row_ctr < in_rows_avail) {
/* Do color conversion to fill the conversion buffer. */
inrows = in_rows_avail - *in_row_ctr;
numrows = prep->next_buf_stop - prep->next_buf_row;
numrows = (int) MIN((JDIMENSION) numrows, inrows);
(*cinfo->cconvert->color_convert) (cinfo, input_buf + *in_row_ctr,
prep->color_buf,
(JDIMENSION) prep->next_buf_row,
numrows);
/* Pad at top of image, if first time through */
if (prep->rows_to_go == cinfo->image_height) {
for (ci = 0; ci < cinfo->num_components; ci++) {
int row;
for (row = 1; row <= cinfo->max_v_samp_factor; row++) {
jcopy_sample_rows(prep->color_buf[ci], 0,
prep->color_buf[ci], -row,
1, cinfo->image_width);
}
}
}
*in_row_ctr += numrows;
prep->next_buf_row += numrows;
prep->rows_to_go -= numrows;
} else {
/* Return for more data, unless we are at the bottom of the image. */
if (prep->rows_to_go != 0)
break;
/* When at bottom of image, pad to fill the conversion buffer. */
if (prep->next_buf_row < prep->next_buf_stop) {
for (ci = 0; ci < cinfo->num_components; ci++) {
expand_bottom_edge(prep->color_buf[ci], cinfo->image_width,
prep->next_buf_row, prep->next_buf_stop);
}
prep->next_buf_row = prep->next_buf_stop;
}
}
/* If we've gotten enough data, downsample a row group. */
if (prep->next_buf_row == prep->next_buf_stop) {
(*cinfo->downsample->downsample) (cinfo,
prep->color_buf,
(JDIMENSION) prep->this_row_group,
output_buf, *out_row_group_ctr);
(*out_row_group_ctr)++;
/* Advance pointers with wraparound as necessary. */
prep->this_row_group += cinfo->max_v_samp_factor;
if (prep->this_row_group >= buf_height)
prep->this_row_group = 0;
if (prep->next_buf_row >= buf_height)
prep->next_buf_row = 0;
prep->next_buf_stop = prep->next_buf_row + cinfo->max_v_samp_factor;
}
}
}
/*
* Create the wrapped-around downsampling input buffer needed for context mode.
*/
LOCAL(void)
create_context_buffer (j_compress_ptr cinfo)
{
my_prep_ptr prep = (my_prep_ptr) cinfo->prep;
int rgroup_height = cinfo->max_v_samp_factor;
int ci, i;
jpeg_component_info * compptr;
JSAMPARRAY true_buffer, fake_buffer;
/* Grab enough space for fake row pointers for all the components;
* we need five row groups' worth of pointers for each component.
*/
fake_buffer = (JSAMPARRAY)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
(cinfo->num_components * 5 * rgroup_height) *
SIZEOF(JSAMPROW));
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
/* Allocate the actual buffer space (3 row groups) for this component.
* We make the buffer wide enough to allow the downsampler to edge-expand
* horizontally within the buffer, if it so chooses.
*/
true_buffer = (*cinfo->mem->alloc_sarray)
((j_common_ptr) cinfo, JPOOL_IMAGE,
(JDIMENSION) (((long) compptr->width_in_blocks * DCTSIZE *
cinfo->max_h_samp_factor) / compptr->h_samp_factor),
(JDIMENSION) (3 * rgroup_height));
/* Copy true buffer row pointers into the middle of the fake row array */
MEMCOPY(fake_buffer + rgroup_height, true_buffer,
3 * rgroup_height * SIZEOF(JSAMPROW));
/* Fill in the above and below wraparound pointers */
for (i = 0; i < rgroup_height; i++) {
fake_buffer[i] = true_buffer[2 * rgroup_height + i];
fake_buffer[4 * rgroup_height + i] = true_buffer[i];
}
prep->color_buf[ci] = fake_buffer + rgroup_height;
fake_buffer += 5 * rgroup_height; /* point to space for next component */
}
}
#endif /* CONTEXT_ROWS_SUPPORTED */
/*
* Initialize preprocessing controller.
*/
GLOBAL(void)
jinit_c_prep_controller (j_compress_ptr cinfo, int need_full_buffer)
{
my_prep_ptr prep;
int ci;
jpeg_component_info * compptr;
if (need_full_buffer) /* safety check */
ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
prep = (my_prep_ptr)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
SIZEOF(my_prep_controller));
cinfo->prep = (struct jpeg_c_prep_controller *) prep;
prep->pub.start_pass = start_pass_prep;
/* Allocate the color conversion buffer.
* We make the buffer wide enough to allow the downsampler to edge-expand
* horizontally within the buffer, if it so chooses.
*/
if (cinfo->downsample->need_context_rows) {
/* Set up to provide context rows */
#ifdef CONTEXT_ROWS_SUPPORTED
prep->pub.pre_process_data = pre_process_context;
create_context_buffer(cinfo);
#else
ERREXIT(cinfo, JERR_NOT_COMPILED);
#endif
} else {
/* No context, just make it tall enough for one row group */
prep->pub.pre_process_data = pre_process_data;
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
prep->color_buf[ci] = (*cinfo->mem->alloc_sarray)
((j_common_ptr) cinfo, JPOOL_IMAGE,
(JDIMENSION) (((long) compptr->width_in_blocks * DCTSIZE *
cinfo->max_h_samp_factor) / compptr->h_samp_factor),
(JDIMENSION) cinfo->max_v_samp_factor);
}
}
}
dlib/external/libjpeg/jcsample.cpp 0 → 100644
View file @ 747088ea
/*
* jcsample.c
*
* Copyright (C) 1991-1996, 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 downsampling routines.
*
* Downsampling input data is counted in "row groups". A row group
* is defined to be max_v_samp_factor pixel rows of each component,
* from which the downsampler produces v_samp_factor sample rows.
* A single row group is processed in each call to the downsampler module.
*
* The downsampler is responsible for edge-expansion of its output data
* to fill an integral number of DCT blocks horizontally. The source buffer
* may be modified if it is helpful for this purpose (the source buffer is
* allocated wide enough to correspond to the desired output width).
* The caller (the prep controller) is responsible for vertical padding.
*
* The downsampler may request "context rows" by setting need_context_rows
* during startup. In this case, the input arrays will contain at least
* one row group's worth of pixels above and below the passed-in data;
* the caller will create dummy rows at image top and bottom by replicating
* the first or last real pixel row.
*
* An excellent reference for image resampling is
* Digital Image Warping, George Wolberg, 1990.
* Pub. by IEEE Computer Society Press, Los Alamitos, CA. ISBN 0-8186-8944-7.
*
* The downsampling algorithm used here is a simple average of the source
* pixels covered by the output pixel. The hi-falutin sampling literature
* refers to this as a "box filter". In general the characteristics of a box
* filter are not very good, but for the specific cases we normally use (1:1
* and 2:1 ratios) the box is equivalent to a "triangle filter" which is not
* nearly so bad. If you intend to use other sampling ratios, you'd be well
* advised to improve this code.
*
* A simple input-smoothing capability is provided. This is mainly intended
* for cleaning up color-dithered GIF input files (if you find it inadequate,
* we suggest using an external filtering program such as pnmconvol). When
* enabled, each input pixel P is replaced by a weighted sum of itself and its
* eight neighbors. P's weight is 1-8*SF and each neighbor's weight is SF,
* where SF = (smoothing_factor / 1024).
* Currently, smoothing is only supported for 2h2v sampling factors.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
/* Pointer to routine to downsample a single component */
typedef JMETHOD(void, downsample1_ptr,
(j_compress_ptr cinfo, jpeg_component_info * compptr,
JSAMPARRAY input_data, JSAMPARRAY output_data));
/* Private subobject */
typedef struct {
struct jpeg_downsampler pub; /* public fields */
/* Downsampling method pointers, one per component */
downsample1_ptr methods[MAX_COMPONENTS];
} my_downsampler;
typedef my_downsampler * my_downsample_ptr;
/*
* Initialize for a downsampling pass.
*/
METHODDEF(void)
start_pass_downsample (j_compress_ptr cinfo)
{
/* no work for now */
}
/*
* Expand a component horizontally from width input_cols to width output_cols,
* by duplicating the rightmost samples.
*/
LOCAL(void)
expand_right_edge (JSAMPARRAY image_data, int num_rows,
JDIMENSION input_cols, JDIMENSION output_cols)
{
register JSAMPROW ptr;
register JSAMPLE pixval;
register int count;
int row;
int numcols = (int) (output_cols - input_cols);
if (numcols > 0) {
for (row = 0; row < num_rows; row++) {
ptr = image_data[row] + input_cols;
pixval = ptr[-1]; /* don't need GETJSAMPLE() here */
for (count = numcols; count > 0; count--)
*ptr++ = pixval;
}
}
}
/*
* Do downsampling for a whole row group (all components).
*
* In this version we simply downsample each component independently.
*/
METHODDEF(void)
sep_downsample (j_compress_ptr cinfo,
JSAMPIMAGE input_buf, JDIMENSION in_row_index,
JSAMPIMAGE output_buf, JDIMENSION out_row_group_index)
{
my_downsample_ptr downsample = (my_downsample_ptr) cinfo->downsample;
int ci;
jpeg_component_info * compptr;
JSAMPARRAY in_ptr, out_ptr;
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
in_ptr = input_buf[ci] + in_row_index;
out_ptr = output_buf[ci] + (out_row_group_index * compptr->v_samp_factor);
(*downsample->methods[ci]) (cinfo, compptr, in_ptr, out_ptr);
}
}
/*
* Downsample pixel values of a single component.
* One row group is processed per call.
* This version handles arbitrary integral sampling ratios, without smoothing.
* Note that this version is not actually used for customary sampling ratios.
*/
METHODDEF(void)
int_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,
JSAMPARRAY input_data, JSAMPARRAY output_data)
{
int inrow, outrow, h_expand, v_expand, numpix, numpix2, h, v;
JDIMENSION outcol, outcol_h; /* outcol_h == outcol*h_expand */
JDIMENSION output_cols = compptr->width_in_blocks * DCTSIZE;
JSAMPROW inptr, outptr;
long outvalue;
h_expand = cinfo->max_h_samp_factor / compptr->h_samp_factor;
v_expand = cinfo->max_v_samp_factor / compptr->v_samp_factor;
numpix = h_expand * v_expand;
numpix2 = numpix/2;
/* Expand input data enough to let all the output samples be generated
* by the standard loop. Special-casing padded output would be more
* efficient.
*/
expand_right_edge(input_data, cinfo->max_v_samp_factor,
cinfo->image_width, output_cols * h_expand);
inrow = 0;
for (outrow = 0; outrow < compptr->v_samp_factor; outrow++) {
outptr = output_data[outrow];
for (outcol = 0, outcol_h = 0; outcol < output_cols;
outcol++, outcol_h += h_expand) {
outvalue = 0;
for (v = 0; v < v_expand; v++) {
inptr = input_data[inrow+v] + outcol_h;
for (h = 0; h < h_expand; h++) {
outvalue += (long) GETJSAMPLE(*inptr++);
}
}
*outptr++ = (JSAMPLE) ((outvalue + numpix2) / numpix);
}
inrow += v_expand;
}
}
/*
* Downsample pixel values of a single component.
* This version handles the special case of a full-size component,
* without smoothing.
*/
METHODDEF(void)
fullsize_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,
JSAMPARRAY input_data, JSAMPARRAY output_data)
{
/* Copy the data */
jcopy_sample_rows(input_data, 0, output_data, 0,
cinfo->max_v_samp_factor, cinfo->image_width);
/* Edge-expand */
expand_right_edge(output_data, cinfo->max_v_samp_factor,
cinfo->image_width, compptr->width_in_blocks * DCTSIZE);
}
/*
* Downsample pixel values of a single component.
* This version handles the common case of 2:1 horizontal and 1:1 vertical,
* without smoothing.
*
* A note about the "bias" calculations: when rounding fractional values to
* integer, we do not want to always round 0.5 up to the next integer.
* If we did that, we'd introduce a noticeable bias towards larger values.
* Instead, this code is arranged so that 0.5 will be rounded up or down at
* alternate pixel locations (a simple ordered dither pattern).
*/
METHODDEF(void)
h2v1_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,
JSAMPARRAY input_data, JSAMPARRAY output_data)
{
int outrow;
JDIMENSION outcol;
JDIMENSION output_cols = compptr->width_in_blocks * DCTSIZE;
register JSAMPROW inptr, outptr;
register int bias;
/* Expand input data enough to let all the output samples be generated
* by the standard loop. Special-casing padded output would be more
* efficient.
*/
expand_right_edge(input_data, cinfo->max_v_samp_factor,
cinfo->image_width, output_cols * 2);
for (outrow = 0; outrow < compptr->v_samp_factor; outrow++) {
outptr = output_data[outrow];
inptr = input_data[outrow];
bias = 0; /* bias = 0,1,0,1,... for successive samples */
for (outcol = 0; outcol < output_cols; outcol++) {
*outptr++ = (JSAMPLE) ((GETJSAMPLE(*inptr) + GETJSAMPLE(inptr[1])
+ bias) >> 1);
bias ^= 1; /* 0=>1, 1=>0 */
inptr += 2;
}
}
}
/*
* Downsample pixel values of a single component.
* This version handles the standard case of 2:1 horizontal and 2:1 vertical,
* without smoothing.
*/
METHODDEF(void)
h2v2_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,
JSAMPARRAY input_data, JSAMPARRAY output_data)
{
int inrow, outrow;
JDIMENSION outcol;
JDIMENSION output_cols = compptr->width_in_blocks * DCTSIZE;
register JSAMPROW inptr0, inptr1, outptr;
register int bias;
/* Expand input data enough to let all the output samples be generated
* by the standard loop. Special-casing padded output would be more
* efficient.
*/
expand_right_edge(input_data, cinfo->max_v_samp_factor,
cinfo->image_width, output_cols * 2);
inrow = 0;
for (outrow = 0; outrow < compptr->v_samp_factor; outrow++) {
outptr = output_data[outrow];
inptr0 = input_data[inrow];
inptr1 = input_data[inrow+1];
bias = 1; /* bias = 1,2,1,2,... for successive samples */
for (outcol = 0; outcol < output_cols; outcol++) {
*outptr++ = (JSAMPLE) ((GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[1]) +
GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[1])
+ bias) >> 2);
bias ^= 3; /* 1=>2, 2=>1 */
inptr0 += 2; inptr1 += 2;
}
inrow += 2;
}
}
#ifdef INPUT_SMOOTHING_SUPPORTED
/*
* Downsample pixel values of a single component.
* This version handles the standard case of 2:1 horizontal and 2:1 vertical,
* with smoothing. One row of context is required.
*/
METHODDEF(void)
h2v2_smooth_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,
JSAMPARRAY input_data, JSAMPARRAY output_data)
{
int inrow, outrow;
JDIMENSION colctr;
JDIMENSION output_cols = compptr->width_in_blocks * DCTSIZE;
register JSAMPROW inptr0, inptr1, above_ptr, below_ptr, outptr;
long membersum, neighsum, memberscale, neighscale;
/* Expand input data enough to let all the output samples be generated
* by the standard loop. Special-casing padded output would be more
* efficient.
*/
expand_right_edge(input_data - 1, cinfo->max_v_samp_factor + 2,
cinfo->image_width, output_cols * 2);
/* We don't bother to form the individual "smoothed" input pixel values;
* we can directly compute the output which is the average of the four
* smoothed values. Each of the four member pixels contributes a fraction
* (1-8*SF) to its own smoothed image and a fraction SF to each of the three
* other smoothed pixels, therefore a total fraction (1-5*SF)/4 to the final
* output. The four corner-adjacent neighbor pixels contribute a fraction
* SF to just one smoothed pixel, or SF/4 to the final output; while the
* eight edge-adjacent neighbors contribute SF to each of two smoothed
* pixels, or SF/2 overall. In order to use integer arithmetic, these
* factors are scaled by 2^16 = 65536.
* Also recall that SF = smoothing_factor / 1024.
*/
memberscale = 16384 - cinfo->smoothing_factor * 80; /* scaled (1-5*SF)/4 */
neighscale = cinfo->smoothing_factor * 16; /* scaled SF/4 */
inrow = 0;
for (outrow = 0; outrow < compptr->v_samp_factor; outrow++) {
outptr = output_data[outrow];
inptr0 = input_data[inrow];
inptr1 = input_data[inrow+1];
above_ptr = input_data[inrow-1];
below_ptr = input_data[inrow+2];
/* Special case for first column: pretend column -1 is same as column 0 */
membersum = GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[1]) +
GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[1]);
neighsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(above_ptr[1]) +
GETJSAMPLE(*below_ptr) + GETJSAMPLE(below_ptr[1]) +
GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[2]) +
GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[2]);
neighsum += neighsum;
neighsum += GETJSAMPLE(*above_ptr) + GETJSAMPLE(above_ptr[2]) +
GETJSAMPLE(*below_ptr) + GETJSAMPLE(below_ptr[2]);
membersum = membersum * memberscale + neighsum * neighscale;
*outptr++ = (JSAMPLE) ((membersum + 32768) >> 16);
inptr0 += 2; inptr1 += 2; above_ptr += 2; below_ptr += 2;
for (colctr = output_cols - 2; colctr > 0; colctr--) {
/* sum of pixels directly mapped to this output element */
membersum = GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[1]) +
GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[1]);
/* sum of edge-neighbor pixels */
neighsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(above_ptr[1]) +
GETJSAMPLE(*below_ptr) + GETJSAMPLE(below_ptr[1]) +
GETJSAMPLE(inptr0[-1]) + GETJSAMPLE(inptr0[2]) +
GETJSAMPLE(inptr1[-1]) + GETJSAMPLE(inptr1[2]);
/* The edge-neighbors count twice as much as corner-neighbors */
neighsum += neighsum;
/* Add in the corner-neighbors */
neighsum += GETJSAMPLE(above_ptr[-1]) + GETJSAMPLE(above_ptr[2]) +
GETJSAMPLE(below_ptr[-1]) + GETJSAMPLE(below_ptr[2]);
/* form final output scaled up by 2^16 */
membersum = membersum * memberscale + neighsum * neighscale;
/* round, descale and output it */
*outptr++ = (JSAMPLE) ((membersum + 32768) >> 16);
inptr0 += 2; inptr1 += 2; above_ptr += 2; below_ptr += 2;
}
/* Special case for last column */
membersum = GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[1]) +
GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[1]);
neighsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(above_ptr[1]) +
GETJSAMPLE(*below_ptr) + GETJSAMPLE(below_ptr[1]) +
GETJSAMPLE(inptr0[-1]) + GETJSAMPLE(inptr0[1]) +
GETJSAMPLE(inptr1[-1]) + GETJSAMPLE(inptr1[1]);
neighsum += neighsum;
neighsum += GETJSAMPLE(above_ptr[-1]) + GETJSAMPLE(above_ptr[1]) +
GETJSAMPLE(below_ptr[-1]) + GETJSAMPLE(below_ptr[1]);
membersum = membersum * memberscale + neighsum * neighscale;
*outptr = (JSAMPLE) ((membersum + 32768) >> 16);
inrow += 2;
}
}
/*
* Downsample pixel values of a single component.
* This version handles the special case of a full-size component,
* with smoothing. One row of context is required.
*/
METHODDEF(void)
fullsize_smooth_downsample (j_compress_ptr cinfo, jpeg_component_info *compptr,
JSAMPARRAY input_data, JSAMPARRAY output_data)
{
int outrow;
JDIMENSION colctr;
JDIMENSION output_cols = compptr->width_in_blocks * DCTSIZE;
register JSAMPROW inptr, above_ptr, below_ptr, outptr;
long membersum, neighsum, memberscale, neighscale;
int colsum, lastcolsum, nextcolsum;
/* Expand input data enough to let all the output samples be generated
* by the standard loop. Special-casing padded output would be more
* efficient.
*/
expand_right_edge(input_data - 1, cinfo->max_v_samp_factor + 2,
cinfo->image_width, output_cols);
/* Each of the eight neighbor pixels contributes a fraction SF to the
* smoothed pixel, while the main pixel contributes (1-8*SF). In order
* to use integer arithmetic, these factors are multiplied by 2^16 = 65536.
* Also recall that SF = smoothing_factor / 1024.
*/
memberscale = 65536L - cinfo->smoothing_factor * 512L; /* scaled 1-8*SF */
neighscale = cinfo->smoothing_factor * 64; /* scaled SF */
for (outrow = 0; outrow < compptr->v_samp_factor; outrow++) {
outptr = output_data[outrow];
inptr = input_data[outrow];
above_ptr = input_data[outrow-1];
below_ptr = input_data[outrow+1];
/* Special case for first column */
colsum = GETJSAMPLE(*above_ptr++) + GETJSAMPLE(*below_ptr++) +
GETJSAMPLE(*inptr);
membersum = GETJSAMPLE(*inptr++);
nextcolsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(*below_ptr) +
GETJSAMPLE(*inptr);
neighsum = colsum + (colsum - membersum) + nextcolsum;
membersum = membersum * memberscale + neighsum * neighscale;
*outptr++ = (JSAMPLE) ((membersum + 32768) >> 16);
lastcolsum = colsum; colsum = nextcolsum;
for (colctr = output_cols - 2; colctr > 0; colctr--) {
membersum = GETJSAMPLE(*inptr++);
above_ptr++; below_ptr++;
nextcolsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(*below_ptr) +
GETJSAMPLE(*inptr);
neighsum = lastcolsum + (colsum - membersum) + nextcolsum;
membersum = membersum * memberscale + neighsum * neighscale;
*outptr++ = (JSAMPLE) ((membersum + 32768) >> 16);
lastcolsum = colsum; colsum = nextcolsum;
}
/* Special case for last column */
membersum = GETJSAMPLE(*inptr);
neighsum = lastcolsum + (colsum - membersum) + colsum;
membersum = membersum * memberscale + neighsum * neighscale;
*outptr = (JSAMPLE) ((membersum + 32768) >> 16);
}
}
#endif /* INPUT_SMOOTHING_SUPPORTED */
/*
* Module initialization routine for downsampling.
* Note that we must select a routine for each component.
*/
GLOBAL(void)
jinit_downsampler (j_compress_ptr cinfo)
{
my_downsample_ptr downsample;
int ci;
jpeg_component_info * compptr;
int smoothok = TRUE;
downsample = (my_downsample_ptr)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
SIZEOF(my_downsampler));
cinfo->downsample = (struct jpeg_downsampler *) downsample;
downsample->pub.start_pass = start_pass_downsample;
downsample->pub.downsample = sep_downsample;
downsample->pub.need_context_rows = FALSE;
if (cinfo->CCIR601_sampling)
ERREXIT(cinfo, JERR_CCIR601_NOTIMPL);
/* Verify we can handle the sampling factors, and set up method pointers */
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
if (compptr->h_samp_factor == cinfo->max_h_samp_factor &&
compptr->v_samp_factor == cinfo->max_v_samp_factor) {
#ifdef INPUT_SMOOTHING_SUPPORTED
if (cinfo->smoothing_factor) {
downsample->methods[ci] = fullsize_smooth_downsample;
downsample->pub.need_context_rows = TRUE;
} else
#endif
downsample->methods[ci] = fullsize_downsample;
} else if (compptr->h_samp_factor * 2 == cinfo->max_h_samp_factor &&
compptr->v_samp_factor == cinfo->max_v_samp_factor) {
smoothok = FALSE;
downsample->methods[ci] = h2v1_downsample;
} else if (compptr->h_samp_factor * 2 == cinfo->max_h_samp_factor &&
compptr->v_samp_factor * 2 == cinfo->max_v_samp_factor) {
#ifdef INPUT_SMOOTHING_SUPPORTED
if (cinfo->smoothing_factor) {
downsample->methods[ci] = h2v2_smooth_downsample;
downsample->pub.need_context_rows = TRUE;
} else
#endif
downsample->methods[ci] = h2v2_downsample;
} else if ((cinfo->max_h_samp_factor % compptr->h_samp_factor) == 0 &&
(cinfo->max_v_samp_factor % compptr->v_samp_factor) == 0) {
smoothok = FALSE;
downsample->methods[ci] = int_downsample;
} else
ERREXIT(cinfo, JERR_FRACT_SAMPLE_NOTIMPL);
}
#ifdef INPUT_SMOOTHING_SUPPORTED
if (cinfo->smoothing_factor && !smoothok)
TRACEMS(cinfo, 0, JTRC_SMOOTH_NOTIMPL);
#endif
}
dlib/external/libjpeg/jdatadst.cpp 0 → 100644
View file @ 747088ea
/*
* jdatadst.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 compression data destination routines for the case of
* emitting JPEG data to a file (or any stdio stream). While these routines
* are sufficient for most applications, some will want to use a different
* destination manager.
* IMPORTANT: we assume that fwrite() will correctly transcribe an array of
* JOCTETs into 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 destination object for stdio output */
typedef struct {
struct jpeg_destination_mgr pub; /* public fields */
FILE * outfile; /* target stream */
JOCTET * buffer; /* start of buffer */
} my_destination_mgr;
typedef my_destination_mgr * my_dest_ptr;
#define OUTPUT_BUF_SIZE 4096 /* choose an efficiently fwrite'able size */
/*
* Initialize destination --- called by jpeg_start_compress
* before any data is actually written.
*/
METHODDEF(void)
init_destination (j_compress_ptr cinfo)
{
my_dest_ptr dest = (my_dest_ptr) cinfo->dest;
/* Allocate the output buffer --- it will be released when done with image */
dest->buffer = (JOCTET *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
OUTPUT_BUF_SIZE * SIZEOF(JOCTET));
dest->pub.next_output_byte = dest->buffer;
dest->pub.free_in_buffer = OUTPUT_BUF_SIZE;
}
/*
* Empty the output buffer --- called whenever buffer fills up.
*
* In typical applications, this should write the entire output buffer
* (ignoring the current state of next_output_byte & free_in_buffer),
* reset the pointer & count to the start of the buffer, and return TRUE
* indicating that the buffer has been dumped.
*
* In applications that need to be able to suspend compression due to output
* overrun, a FALSE return indicates that the buffer cannot be emptied now.
* In this situation, the compressor will return to its caller (possibly with
* an indication that it has not accepted all the supplied scanlines). The
* application should resume compression after it has made more room in the
* output buffer. Note that there are substantial restrictions on the use of
* suspension --- see the documentation.
*
* When suspending, the compressor will back up to a convenient restart point
* (typically the start of the current MCU). next_output_byte & free_in_buffer
* indicate where the restart point will be if the current call returns FALSE.
* Data beyond this point will be regenerated after resumption, so do not
* write it out when emptying the buffer externally.
*/
METHODDEF(int)
empty_output_buffer (j_compress_ptr cinfo)
{
my_dest_ptr dest = (my_dest_ptr) cinfo->dest;
if (JFWRITE(dest->outfile, dest->buffer, OUTPUT_BUF_SIZE) !=
(size_t) OUTPUT_BUF_SIZE)
ERREXIT(cinfo, JERR_FILE_WRITE);
dest->pub.next_output_byte = dest->buffer;
dest->pub.free_in_buffer = OUTPUT_BUF_SIZE;
return TRUE;
}
/*
* Terminate destination --- called by jpeg_finish_compress
* after all data has been written. Usually needs to flush buffer.
*
* 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_destination (j_compress_ptr cinfo)
{
my_dest_ptr dest = (my_dest_ptr) cinfo->dest;
size_t datacount = OUTPUT_BUF_SIZE - dest->pub.free_in_buffer;
/* Write any data remaining in the buffer */
if (datacount > 0) {
if (JFWRITE(dest->outfile, dest->buffer, datacount) != datacount)
ERREXIT(cinfo, JERR_FILE_WRITE);
}
fflush(dest->outfile);
/* Make sure we wrote the output file OK */
if (ferror(dest->outfile))
ERREXIT(cinfo, JERR_FILE_WRITE);
}
/*
* Prepare for output to a stdio stream.
* The caller must have already opened the stream, and is responsible
* for closing it after finishing compression.
*/
GLOBAL(void)
jpeg_stdio_dest (j_compress_ptr cinfo, FILE * outfile)
{
my_dest_ptr dest;
/* The destination object is made permanent so that multiple JPEG images
* can be written to the same file without re-executing jpeg_stdio_dest.
* This makes it dangerous to use this manager and a different destination
* manager serially with the same JPEG object, because their private object
* sizes may be different. Caveat programmer.
*/
if (cinfo->dest == NULL) { /* first time for this JPEG object? */
cinfo->dest = (struct jpeg_destination_mgr *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
SIZEOF(my_destination_mgr));
}
dest = (my_dest_ptr) cinfo->dest;
dest->pub.init_destination = init_destination;
dest->pub.empty_output_buffer = empty_output_buffer;
dest->pub.term_destination = term_destination;
dest->outfile = outfile;
}
dlib/external/libjpeg/jfdctflt.cpp 0 → 100644
View file @ 747088ea
/*
* jfdctflt.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 a floating-point implementation of the
* forward DCT (Discrete Cosine Transform).
*
* This implementation should be more accurate than either of the integer
* DCT implementations. However, it may not give the same results on all
* machines because of differences in roundoff behavior. Speed will depend
* on the hardware's floating point capacity.
*
* A 2-D DCT can be done by 1-D DCT on each row followed by 1-D DCT
* on each column. Direct algorithms are also available, but they are
* much more complex and seem not to be any faster when reduced to code.
*
* This implementation is based on Arai, Agui, and Nakajima's algorithm for
* scaled DCT. Their original paper (Trans. IEICE E-71(11):1095) is in
* Japanese, but the algorithm is described in the Pennebaker & Mitchell
* JPEG textbook (see REFERENCES section in file README). The following code
* is based directly on figure 4-8 in P&M.
* While an 8-point DCT cannot be done in less than 11 multiplies, it is
* possible to arrange the computation so that many of the multiplies are
* simple scalings of the final outputs. These multiplies can then be
* folded into the multiplications or divisions by the JPEG quantization
* table entries. The AA&N method leaves only 5 multiplies and 29 adds
* to be done in the DCT itself.
* The primary disadvantage of this method is that with a fixed-point
* implementation, accuracy is lost due to imprecise representation of the
* scaled quantization values. However, that problem does not arise if
* we use floating point arithmetic.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
#include "jdct.h" /* Private declarations for DCT subsystem */
#ifdef DCT_FLOAT_SUPPORTED
/*
* This module is specialized to the case DCTSIZE = 8.
*/
#if DCTSIZE != 8
Sorry, this code only copes with 8x8 DCTs. /* deliberate syntax err */
#endif
/*
* Perform the forward DCT on one block of samples.
*/
GLOBAL(void)
jpeg_fdct_float (FAST_FLOAT * data)
{
FAST_FLOAT tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;
FAST_FLOAT tmp10, tmp11, tmp12, tmp13;
FAST_FLOAT z1, z2, z3, z4, z5, z11, z13;
FAST_FLOAT *dataptr;
int ctr;
/* Pass 1: process rows. */
dataptr = data;
for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {
tmp0 = dataptr[0] + dataptr[7];
tmp7 = dataptr[0] - dataptr[7];
tmp1 = dataptr[1] + dataptr[6];
tmp6 = dataptr[1] - dataptr[6];
tmp2 = dataptr[2] + dataptr[5];
tmp5 = dataptr[2] - dataptr[5];
tmp3 = dataptr[3] + dataptr[4];
tmp4 = dataptr[3] - dataptr[4];
/* Even part */
tmp10 = tmp0 + tmp3; /* phase 2 */
tmp13 = tmp0 - tmp3;
tmp11 = tmp1 + tmp2;
tmp12 = tmp1 - tmp2;
dataptr[0] = tmp10 + tmp11; /* phase 3 */
dataptr[4] = tmp10 - tmp11;
z1 = (tmp12 + tmp13) * ((FAST_FLOAT) 0.707106781); /* c4 */
dataptr[2] = tmp13 + z1; /* phase 5 */
dataptr[6] = tmp13 - z1;
/* Odd part */
tmp10 = tmp4 + tmp5; /* phase 2 */
tmp11 = tmp5 + tmp6;
tmp12 = tmp6 + tmp7;
/* The rotator is modified from fig 4-8 to avoid extra negations. */
z5 = (tmp10 - tmp12) * ((FAST_FLOAT) 0.382683433); /* c6 */
z2 = ((FAST_FLOAT) 0.541196100) * tmp10 + z5; /* c2-c6 */
z4 = ((FAST_FLOAT) 1.306562965) * tmp12 + z5; /* c2+c6 */
z3 = tmp11 * ((FAST_FLOAT) 0.707106781); /* c4 */
z11 = tmp7 + z3; /* phase 5 */
z13 = tmp7 - z3;
dataptr[5] = z13 + z2; /* phase 6 */
dataptr[3] = z13 - z2;
dataptr[1] = z11 + z4;
dataptr[7] = z11 - z4;
dataptr += DCTSIZE; /* advance pointer to next row */
}
/* Pass 2: process columns. */
dataptr = data;
for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {
tmp0 = dataptr[DCTSIZE*0] + dataptr[DCTSIZE*7];
tmp7 = dataptr[DCTSIZE*0] - dataptr[DCTSIZE*7];
tmp1 = dataptr[DCTSIZE*1] + dataptr[DCTSIZE*6];
tmp6 = dataptr[DCTSIZE*1] - dataptr[DCTSIZE*6];
tmp2 = dataptr[DCTSIZE*2] + dataptr[DCTSIZE*5];
tmp5 = dataptr[DCTSIZE*2] - dataptr[DCTSIZE*5];
tmp3 = dataptr[DCTSIZE*3] + dataptr[DCTSIZE*4];
tmp4 = dataptr[DCTSIZE*3] - dataptr[DCTSIZE*4];
/* Even part */
tmp10 = tmp0 + tmp3; /* phase 2 */
tmp13 = tmp0 - tmp3;
tmp11 = tmp1 + tmp2;
tmp12 = tmp1 - tmp2;
dataptr[DCTSIZE*0] = tmp10 + tmp11; /* phase 3 */
dataptr[DCTSIZE*4] = tmp10 - tmp11;
z1 = (tmp12 + tmp13) * ((FAST_FLOAT) 0.707106781); /* c4 */
dataptr[DCTSIZE*2] = tmp13 + z1; /* phase 5 */
dataptr[DCTSIZE*6] = tmp13 - z1;
/* Odd part */
tmp10 = tmp4 + tmp5; /* phase 2 */
tmp11 = tmp5 + tmp6;
tmp12 = tmp6 + tmp7;
/* The rotator is modified from fig 4-8 to avoid extra negations. */
z5 = (tmp10 - tmp12) * ((FAST_FLOAT) 0.382683433); /* c6 */
z2 = ((FAST_FLOAT) 0.541196100) * tmp10 + z5; /* c2-c6 */
z4 = ((FAST_FLOAT) 1.306562965) * tmp12 + z5; /* c2+c6 */
z3 = tmp11 * ((FAST_FLOAT) 0.707106781); /* c4 */
z11 = tmp7 + z3; /* phase 5 */
z13 = tmp7 - z3;
dataptr[DCTSIZE*5] = z13 + z2; /* phase 6 */
dataptr[DCTSIZE*3] = z13 - z2;
dataptr[DCTSIZE*1] = z11 + z4;
dataptr[DCTSIZE*7] = z11 - z4;
dataptr++; /* advance pointer to next column */
}
}
#endif /* DCT_FLOAT_SUPPORTED */
dlib/external/libjpeg/jfdctfst.cpp 0 → 100644
View file @ 747088ea
/*
* jfdctfst.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 a fast, not so accurate integer implementation of the
* forward DCT (Discrete Cosine Transform).
*
* A 2-D DCT can be done by 1-D DCT on each row followed by 1-D DCT
* on each column. Direct algorithms are also available, but they are
* much more complex and seem not to be any faster when reduced to code.
*
* This implementation is based on Arai, Agui, and Nakajima's algorithm for
* scaled DCT. Their original paper (Trans. IEICE E-71(11):1095) is in
* Japanese, but the algorithm is described in the Pennebaker & Mitchell
* JPEG textbook (see REFERENCES section in file README). The following code
* is based directly on figure 4-8 in P&M.
* While an 8-point DCT cannot be done in less than 11 multiplies, it is
* possible to arrange the computation so that many of the multiplies are
* simple scalings of the final outputs. These multiplies can then be
* folded into the multiplications or divisions by the JPEG quantization
* table entries. The AA&N method leaves only 5 multiplies and 29 adds
* to be done in the DCT itself.
* The primary disadvantage of this method is that with fixed-point math,
* accuracy is lost due to imprecise representation of the scaled
* quantization values. The smaller the quantization table entry, the less
* precise the scaled value, so this implementation does worse with high-
* quality-setting files than with low-quality ones.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
#include "jdct.h" /* Private declarations for DCT subsystem */
#ifdef DCT_IFAST_SUPPORTED
/*
* This module is specialized to the case DCTSIZE = 8.
*/
#if DCTSIZE != 8
Sorry, this code only copes with 8x8 DCTs. /* deliberate syntax err */
#endif
/* Scaling decisions are generally the same as in the LL&M algorithm;
* see jfdctint.c for more details. However, we choose to descale
* (right shift) multiplication products as soon as they are formed,
* rather than carrying additional fractional bits into subsequent additions.
* This compromises accuracy slightly, but it lets us save a few shifts.
* More importantly, 16-bit arithmetic is then adequate (for 8-bit samples)
* everywhere except in the multiplications proper; this saves a good deal
* of work on 16-bit-int machines.
*
* Again to save a few shifts, the intermediate results between pass 1 and
* pass 2 are not upscaled, but are represented only to integral precision.
*
* A final compromise is to represent the multiplicative constants to only
* 8 fractional bits, rather than 13. This saves some shifting work on some
* machines, and may also reduce the cost of multiplication (since there
* are fewer one-bits in the constants).
*/
#define CONST_BITS 8
/* Some C compilers fail to reduce "FIX(constant)" at compile time, thus
* causing a lot of useless floating-point operations at run time.
* To get around this we use the following pre-calculated constants.
* If you change CONST_BITS you may want to add appropriate values.
* (With a reasonable C compiler, you can just rely on the FIX() macro...)
*/
#if CONST_BITS == 8
#define FIX_0_382683433 ((long) 98) /* FIX(0.382683433) */
#define FIX_0_541196100 ((long) 139) /* FIX(0.541196100) */
#define FIX_0_707106781 ((long) 181) /* FIX(0.707106781) */
#define FIX_1_306562965 ((long) 334) /* FIX(1.306562965) */
#else
#define FIX_0_382683433 FIX(0.382683433)
#define FIX_0_541196100 FIX(0.541196100)
#define FIX_0_707106781 FIX(0.707106781)
#define FIX_1_306562965 FIX(1.306562965)
#endif
/* We can gain a little more speed, with a further compromise in accuracy,
* by omitting the addition in a descaling shift. This yields an incorrectly
* rounded result half the time...
*/
#ifndef USE_ACCURATE_ROUNDING
#undef DESCALE
#define DESCALE(x,n) RIGHT_SHIFT(x, n)
#endif
/* Multiply a DCTELEM variable by an long constant, and immediately
* descale to yield a DCTELEM result.
*/
#define MULTIPLY(var,const) ((DCTELEM) DESCALE((var) * (const), CONST_BITS))
/*
* Perform the forward DCT on one block of samples.
*/
GLOBAL(void)
jpeg_fdct_ifast (DCTELEM * data)
{
DCTELEM tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;
DCTELEM tmp10, tmp11, tmp12, tmp13;
DCTELEM z1, z2, z3, z4, z5, z11, z13;
DCTELEM *dataptr;
int ctr;
SHIFT_TEMPS
/* Pass 1: process rows. */
dataptr = data;
for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {
tmp0 = dataptr[0] + dataptr[7];
tmp7 = dataptr[0] - dataptr[7];
tmp1 = dataptr[1] + dataptr[6];
tmp6 = dataptr[1] - dataptr[6];
tmp2 = dataptr[2] + dataptr[5];
tmp5 = dataptr[2] - dataptr[5];
tmp3 = dataptr[3] + dataptr[4];
tmp4 = dataptr[3] - dataptr[4];
/* Even part */
tmp10 = tmp0 + tmp3; /* phase 2 */
tmp13 = tmp0 - tmp3;
tmp11 = tmp1 + tmp2;
tmp12 = tmp1 - tmp2;
dataptr[0] = tmp10 + tmp11; /* phase 3 */
dataptr[4] = tmp10 - tmp11;
z1 = MULTIPLY(tmp12 + tmp13, FIX_0_707106781); /* c4 */
dataptr[2] = tmp13 + z1; /* phase 5 */
dataptr[6] = tmp13 - z1;
/* Odd part */
tmp10 = tmp4 + tmp5; /* phase 2 */
tmp11 = tmp5 + tmp6;
tmp12 = tmp6 + tmp7;
/* The rotator is modified from fig 4-8 to avoid extra negations. */
z5 = MULTIPLY(tmp10 - tmp12, FIX_0_382683433); /* c6 */
z2 = MULTIPLY(tmp10, FIX_0_541196100) + z5; /* c2-c6 */
z4 = MULTIPLY(tmp12, FIX_1_306562965) + z5; /* c2+c6 */
z3 = MULTIPLY(tmp11, FIX_0_707106781); /* c4 */
z11 = tmp7 + z3; /* phase 5 */
z13 = tmp7 - z3;
dataptr[5] = z13 + z2; /* phase 6 */
dataptr[3] = z13 - z2;
dataptr[1] = z11 + z4;
dataptr[7] = z11 - z4;
dataptr += DCTSIZE; /* advance pointer to next row */
}
/* Pass 2: process columns. */
dataptr = data;
for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {
tmp0 = dataptr[DCTSIZE*0] + dataptr[DCTSIZE*7];
tmp7 = dataptr[DCTSIZE*0] - dataptr[DCTSIZE*7];
tmp1 = dataptr[DCTSIZE*1] + dataptr[DCTSIZE*6];
tmp6 = dataptr[DCTSIZE*1] - dataptr[DCTSIZE*6];
tmp2 = dataptr[DCTSIZE*2] + dataptr[DCTSIZE*5];
tmp5 = dataptr[DCTSIZE*2] - dataptr[DCTSIZE*5];
tmp3 = dataptr[DCTSIZE*3] + dataptr[DCTSIZE*4];
tmp4 = dataptr[DCTSIZE*3] - dataptr[DCTSIZE*4];
/* Even part */
tmp10 = tmp0 + tmp3; /* phase 2 */
tmp13 = tmp0 - tmp3;
tmp11 = tmp1 + tmp2;
tmp12 = tmp1 - tmp2;
dataptr[DCTSIZE*0] = tmp10 + tmp11; /* phase 3 */
dataptr[DCTSIZE*4] = tmp10 - tmp11;
z1 = MULTIPLY(tmp12 + tmp13, FIX_0_707106781); /* c4 */
dataptr[DCTSIZE*2] = tmp13 + z1; /* phase 5 */
dataptr[DCTSIZE*6] = tmp13 - z1;
/* Odd part */
tmp10 = tmp4 + tmp5; /* phase 2 */
tmp11 = tmp5 + tmp6;
tmp12 = tmp6 + tmp7;
/* The rotator is modified from fig 4-8 to avoid extra negations. */
z5 = MULTIPLY(tmp10 - tmp12, FIX_0_382683433); /* c6 */
z2 = MULTIPLY(tmp10, FIX_0_541196100) + z5; /* c2-c6 */
z4 = MULTIPLY(tmp12, FIX_1_306562965) + z5; /* c2+c6 */
z3 = MULTIPLY(tmp11, FIX_0_707106781); /* c4 */
z11 = tmp7 + z3; /* phase 5 */
z13 = tmp7 - z3;
dataptr[DCTSIZE*5] = z13 + z2; /* phase 6 */
dataptr[DCTSIZE*3] = z13 - z2;
dataptr[DCTSIZE*1] = z11 + z4;
dataptr[DCTSIZE*7] = z11 - z4;
dataptr++; /* advance pointer to next column */
}
}
#endif /* DCT_IFAST_SUPPORTED */
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