Small documentation update (#8558)

* Merged commit includes the following changes:
253126424  by Andre Araujo:

    Scripts to compute metrics for Google Landmarks dataset.

    Also, a small fix to metric in retrieval case: avoids duplicate predicted images.

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253118971  by Andre Araujo:

    Metrics for Google Landmarks dataset.

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253106953  by Andre Araujo:

    Library to read files from Google Landmarks challenges.

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250700636  by Andre Araujo:

    Handle case of aggregation extraction with empty set of input features.

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250516819  by Andre Araujo:

    Add minimum size for DELF extractor.

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250435822  by Andre Araujo:

    Add max_image_size/min_image_size for open-source DELF proto / module.

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250414606  by Andre Araujo:

    Refactor extract_aggregation to allow reuse with different datasets.

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250356863  by Andre Araujo:

    Remove unnecessary cmd_args variable from boxes_and_features_extraction.

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249783379  by Andre Araujo:

    Create directory for writing mapping file if it does not exist.

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249581591  by Andre Araujo:

    Refactor scripts to extract boxes and features from images in Revisited datasets.
    Also, change tf.logging.info --> print for easier logging in open source code.

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249511821  by Andre Araujo:

    Small change to function for file/directory handling.

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249289499  by Andre Araujo:

    Internal change.

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PiperOrigin-RevId: 253126424

* Updating DELF init to adjust to latest changes

* Editing init files for python packages

* Edit D2R dataset reader to work with py3.

PiperOrigin-RevId: 253135576

* DELF package: fix import ordering

* Adding new requirements to setup.py

* Adding init file for training dir

* Merged commit includes the following changes:

FolderOrigin-RevId: /google/src/cloud/andrearaujo/delf_oss/google3/..

* Adding init file for training subdirs

* Working version of DELF training

* Internal change.

PiperOrigin-RevId: 253248648

* Fix variance loading in open-source code.

PiperOrigin-RevId: 260619120

* Separate image re-ranking as a standalone library, and add metric writing to dataset library.

PiperOrigin-RevId: 260998608

* Tool to read written D2R Revisited datasets metrics file. Test is added.

Also adds a unit test for previously-existing SaveMetricsFile function.

PiperOrigin-RevId: 263361410

* Add optional resize factor for feature extraction.

PiperOrigin-RevId: 264437080

* Fix NumPy's new version spacing changes.

PiperOrigin-RevId: 265127245

* Maker image matching function visible, and add support for RANSAC seed.

PiperOrigin-RevId: 277177468

* Avoid matplotlib failure due to missing display backend.

PiperOrigin-RevId: 287316435

* Removes tf.contrib dependency.

PiperOrigin-RevId: 288842237

* Fix tf contrib removal for feature_aggregation_extractor.

PiperOrigin-RevId: 289487669

* Merged commit includes the following changes:
309118395  by Andre Araujo:

    Make DELF open-source code compatible with TF2.

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309067582  by Andre Araujo:

    Handle image resizing rounding properly for python extraction.

    New behavior is tested with unit tests.

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308690144  by Andre Araujo:

    Several changes to improve DELF model/training code and make it work in TF 2.1.0:
    - Rename some files for better clarity
    - Using compat.v1 versions of functions
    - Formatting changes
    - Using more appropriate TF function names

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308689397  by Andre Araujo:

    Internal change.

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308341315  by Andre Araujo:

    Remove old slim dependency in DELF open-source model.

    This avoids issues with requiring old TF-v1, making it compatible with latest TF.

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306777559  by Andre Araujo:

    Internal change

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304505811  by Andre Araujo:

    Raise error during geometric verification if local features have different dimensionalities.

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301739992  by Andre Araujo:

    Transform some geometric verification constants into arguments, to allow custom matching.

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301300324  by Andre Araujo:

    Apply name change(experimental_run_v2 -> run) for all callers in Tensorflow.

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299919057  by Andre Araujo:

    Automated refactoring to make code Python 3 compatible.

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297953698  by Andre Araujo:

    Explicitly replace "import tensorflow" with "tensorflow.compat.v1" for TF2.x migration

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297521242  by Andre Araujo:

    Explicitly replace "import tensorflow" with "tensorflow.compat.v1" for TF2.x migration

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297278247  by Andre Araujo:

    Explicitly replace "import tensorflow" with "tensorflow.compat.v1" for TF2.x migration

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297270405  by Andre Araujo:

    Explicitly replace "import tensorflow" with "tensorflow.compat.v1" for TF2.x migration

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297238741  by Andre Araujo:

    Explicitly replace "import tensorflow" with "tensorflow.compat.v1" for TF2.x migration

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297108605  by Andre Araujo:

    Explicitly replace "import tensorflow" with "tensorflow.compat.v1" for TF2.x migration

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294676131  by Andre Araujo:

    Add option to resize images to square resolutions without aspect ratio preservation.

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293849641  by Andre Araujo:

    Internal change.

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293840896  by Andre Araujo:

    Changing Slim import to tf_slim codebase.

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293661660  by Andre Araujo:

    Allow the delf training script to read from TFRecords dataset.

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291755295  by Andre Araujo:

    Internal change.

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291448508  by Andre Araujo:

    Internal change.

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291414459  by Andre Araujo:

    Adding train script.

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291384336  by Andre Araujo:

    Adding model export script and test.

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291260565  by Andre Araujo:

    Adding placeholder for Google Landmarks dataset.

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291205548  by Andre Araujo:

    Definition of DELF model using Keras ResNet50 as backbone.

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289500793  by Andre Araujo:

    Add TFRecord building script for delf.

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PiperOrigin-RevId: 309118395

* Updating README, dependency versions

* Updating training README

* Fixing init import of export_model

* Fixing init import of export_model_utils

* tkinter in INSTALL_INSTRUCTIONS

* Merged commit includes the following changes:

FolderOrigin-RevId: /google/src/cloud/andrearaujo/delf_oss/google3/..

* INSTALL_INSTRUCTIONS mentioning different cloning options

* Updating required TF version, since 2.1 is not available in pip

* Internal change.

PiperOrigin-RevId: 309136003

* Fix missing string_input_producer and start_queue_runners in TF2.

PiperOrigin-RevId: 309437512

* Handle RANSAC from skimage's latest versions.

PiperOrigin-RevId: 310170897

* DELF 2.1 version: badge and setup.py updated

* Add TF version badge in INSTALL_INSTRUCTIONS and paper badges in README

* Add paper badges in paper instructions

* Add paper badge to landmark detection instructions

* Small update to DELF training README

* Merged commit includes the following changes:
312614961  by Andre Araujo:

    Instructions/code to reproduce DELG paper results.

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312523414  by Andre Araujo:

    Fix a minor bug when post-process extracted features, format config.delf_global_config.image_scales_ind to a list.

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312340276  by Andre Araujo:

    Add support for global feature extraction in DELF open-source codebase.

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311031367  by Andre Araujo:

    Add use_square_images as an option in DELF config. The default value is false. if it is set, then images are resized to square resolution before feature extraction (e.g. Starburst use case. ) Thought for a while, whether to have two constructor of DescriptorToImageTemplate, but in the end, decide to only keep one, may be less confusing.

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310658638  by Andre Araujo:

    Option for producing local feature-based image match visualization.

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PiperOrigin-RevId: 312614961

* DELF README update / DELG instructions

* DELF README update

* DELG instructions update

* Merged commit includes the following changes:

PiperOrigin-RevId: 312695597

* Merged commit includes the following changes:
312754894  by Andre Araujo:

    Code edits / instructions to reproduce GLDv2 results.

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PiperOrigin-RevId: 312754894

* Markdown updates after adding GLDv2 stuff

* Small updates to DELF README

* Clarify that library must be installed before reproducing results

research/delf/delf/python/delg/DELG_INSTRUCTIONS.md

@@ -6,6 +6,12 @@ These instructions can be used to reproduce the results from the
 [DELG paper](https://arxiv.org/abs/2001.05027) for the Revisited Oxford/Paris
 datasets.
 
+### Install DELF library
+
+To be able to use this code, please follow
+[these instructions](../../../INSTALL_INSTRUCTIONS.md) to properly install the
+DELF library.
+
 ### Download datasets
 
 ```bash

research/delf/delf/python/google_landmarks_dataset/README.md

@@ -15,6 +15,12 @@ file reading / metric computation modules.
 For more details on the dataset, please refer to its
 [website](https://github.com/cvdfoundation/google-landmark).
 
+### Install DELF library
+
+To be able to use this code, please follow
+[these instructions](../../../INSTALL_INSTRUCTIONS.md) to properly install the
+DELF library.
+
 ### Download Revisited Oxford/Paris datasets
 
 ```bash

research/delf/delf/python/training/README.md

 # DELF training instructions
 
+## Install DELF library
+
+To be able to use this code, please follow
+[these instructions](../../../INSTALL_INSTRUCTIONS.md) to properly install the
+DELF library.
+
 ## Data preparation
 
 See the