Merged commit includes the following changes:

[lzr-official]

247226201 by ronnyvotel:

Updating the visualization tools to accept unique_ids for color coding.

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247067830 by Zhichao Lu:

Add box_encodings_clip_range options for the convolutional box predictor (for TPU compatibility).

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246888475 by Zhichao Lu:

Remove unused _update_eval_steps function.

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246163259 by lzc:

Add a gather op that can handle ignore indices (which are "-1"s in this case).

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246084944 by Zhichao Lu:

Keras based implementation for SSD + MobilenetV2 + FPN.

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245544227 by rathodv:

Add batch_get_targets method to target assigner module to gather any groundtruth tensors based on the results of target assigner.

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245540854 by rathodv:

Update target assigner to return match tensor instead of a match object.

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245434441 by Zhichao Lu:

Add README for tpu_exporters package.

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245381834 by lzc:

Internal change.

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245298983 by Zhichao Lu:

Add conditional_shape_resizer to config_util

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245134666 by Zhichao Lu:

Adds ConditionalShapeResizer to the ImageResizer proto which enables resizing only if input image height or width is is greater or smaller than a certain size. Also enables specification of resize method in resize_to_{max, min}_dimension methods.

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245093975 by Zhichao Lu:

Exporting SavedModel for Object Detection TPU inference. (faster-rcnn)

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245072421 by Zhichao Lu:

Adds a new image resizing method "resize_to_max_dimension" which resizes images only if a dimension is greater than the maximum desired value while maintaining aspect ratio.

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244946998 by lzc:

Internal Changes.

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244943693 by Zhichao Lu:

Add a custom config to mobilenet v2 that makes it more detection friendly.

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244754158 by derekjchow:

Internal change.

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244699875 by Zhichao Lu:

Add check_range=False to box_list_ops.to_normalized_coordinates when training
for instance segmentation.  This is consistent with other calls when training
for object detection.  There could be wrongly annotated boxes in the dataset.

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244507425 by rathodv:

Support bfloat16 for ssd models.

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244399982 by Zhichao Lu:

Exporting SavedModel for Object Detection TPU inference. (ssd)

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244209387 by Zhichao Lu:

Internal change.

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243922296 by rathodv:

Change `raw_detection_scores` to contain softmax/sigmoid scores (not logits) for `raw_ detection_boxes`.

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243883978 by Zhichao Lu:

Add a sample fully conv config.

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243369455 by Zhichao Lu:

Fix regularization loss gap in Keras and Slim.

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243292002 by lzc:

Internal changes.

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243097958 by Zhichao Lu:

Exporting SavedModel for Object Detection TPU inference. (ssd model)

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243007177 by Zhichao Lu:

Exporting SavedModel for Object Detection TPU inference. (ssd model)

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242776550 by Zhichao Lu:

Make object detection pre-processing run on GPU.  tf.map_fn() uses
TensorArrayV3 ops, which have no int32 GPU implementation.  Cast to int64,
then cast back to int32.

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242723128 by Zhichao Lu:

Using sorted dictionaries for additional heads in non_max_suppression to ensure tensor order

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242495311 by Zhichao Lu:

Update documentation to reflect new TFLite examples repo location

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242230527 by Zhichao Lu:

Fix Dropout bugs for WeightSharedConvolutionalBoxPred.

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242226573 by Zhichao Lu:

Create Keras-based WeightSharedConvolutionalBoxPredictor.

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241806074 by Zhichao Lu:

Add inference in unit tests of TFX OD template.

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241641498 by lzc:

Internal change.

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241637481 by Zhichao Lu:

matmul_crop_and_resize(): Switch to dynamic shaping, so that not all dimensions are required to be known.

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241429980 by Zhichao Lu:

Internal change

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241167237 by Zhichao Lu:

Adds a faster_rcnn_inception_resnet_v2 Keras feature extractor, and updates the model builder to construct it.

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241088616 by Zhichao Lu:

Make it compatible with different dtype, e.g. float32, bfloat16, etc.

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240897364 by lzc:

Use image_np_expanded in object_detection_tutorial notebook.

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240890393 by Zhichao Lu:

Disable multicore inference for OD template as its not yet compatible.

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240352168 by Zhichao Lu:

Make SSDResnetV1FpnFeatureExtractor not protected to allow inheritance.

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240351470 by lzc:

Internal change.

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239878928 by Zhichao Lu:

Defines Keras box predictors for Faster RCNN and RFCN

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239872103 by Zhichao Lu:

Delete duplicated inputs in test.

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239714273 by Zhichao Lu:

Adding scope variable to all class heads

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239698643 by Zhichao Lu:

Create FPN feature extractor for object detection.

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239696657 by Zhichao Lu:

Internal Change.

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239299404 by Zhichao Lu:

Allows the faster rcnn meta-architecture to support Keras subcomponents

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238502595 by Zhichao Lu:

Lay the groundwork for symmetric quantization.

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238496885 by Zhichao Lu:

Add flexible_grid_anchor_generator

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238138727 by lzc:

Remove dead code.

_USE_C_SHAPES has been forced True in TensorFlow releases since
TensorFlow 1.9
(https://github.com/tensorflow/tensorflow/commit/1d74a69443f741e69f9f52cb6bc2940b4d4ae3b7)

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238123936 by rathodv:

Add num_matched_groundtruth summary to target assigner in SSD.

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238103345 by ronnyvotel:

Raising error if input file pattern does not match any files.
Also printing the number of evaluation images for coco metrics.

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238044081 by Zhichao Lu:

Fix docstring to state the correct dimensionality of `class_predictions_with_background`.

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237920279 by Zhichao Lu:

[XLA] Rework debug flags for dumping HLO.

The following flags (usually passed via the XLA_FLAGS envvar) are removed:

  xla_dump_computations_to
  xla_dump_executions_to
  xla_dump_ir_to
  xla_dump_optimized_hlo_proto_to
  xla_dump_per_pass_hlo_proto_to
  xla_dump_unoptimized_hlo_proto_to
  xla_generate_hlo_graph
  xla_generate_hlo_text_to
  xla_hlo_dump_as_html
  xla_hlo_graph_path
  xla_log_hlo_text

The following new flags are added:

  xla_dump_to
  xla_dump_hlo_module_re
  xla_dump_hlo_pass_re
  xla_dump_hlo_as_text
  xla_dump_hlo_as_proto
  xla_dump_hlo_as_dot
  xla_dump_hlo_as_url
  xla_dump_hlo_as_html
  xla_dump_ir
  xla_dump_hlo_snapshots

The default is not to dump anything at all, but as soon as some dumping flag is
specified, we enable the following defaults (most of which can be overridden).

 * dump to stdout (overridden by --xla_dump_to)
 * dump HLO modules at the very beginning and end of the optimization pipeline
 * don't dump between any HLO passes (overridden by --xla_dump_hlo_pass_re)
 * dump all HLO modules (overridden by --xla_dump_hlo_module_re)
 * dump in textual format (overridden by
   --xla_dump_hlo_as_{text,proto,dot,url,html}).

For example, to dump optimized and unoptimized HLO text and protos to /tmp/foo,
pass

  --xla_dump_to=/tmp/foo --xla_dump_hlo_as_text --xla_dump_hlo_as_proto

For details on these flags' meanings, see xla.proto.

The intent of this change is to make dumping both simpler to use and more
powerful.

For example:

 * Previously there was no way to dump the HLO module during the pass pipeline
   in HLO text format; the only option was --dump_per_pass_hlo_proto_to, which
   dumped in proto format.

   Now this is --xla_dump_pass_re=.* --xla_dump_hlo_as_text.  (In fact, the
   second flag is not necessary in this case, as dumping as text is the
   default.)

 * Previously there was no way to dump HLO as a graph before and after
   compilation; the only option was --xla_generate_hlo_graph, which would dump
   before/after every pass.

   Now this is --xla_dump_hlo_as_{dot,url,html} (depending on what format you
   want the graph in).

 * Previously, there was no coordination between the filenames written by the
   various flags, so info about one module might be dumped with various
   filename prefixes.  Now the filenames are consistent and all dumps from a
   particular module are next to each other.

If you only specify some of these flags, we try to figure out what you wanted.
For example:

 * --xla_dump_to implies --xla_dump_hlo_as_text unless you specify some
   other --xla_dump_as_* flag.

 * --xla_dump_hlo_as_text or --xla_dump_ir implies dumping to stdout unless you
   specify a different --xla_dump_to directory.  You can explicitly dump to
   stdout with --xla_dump_to=-.

As part of this change, I simplified the debugging code in the HLO passes for
dumping HLO modules.  Previously, many tests explicitly VLOG'ed the HLO module
before, after, and sometimes during the pass.  I removed these VLOGs.  If you
want dumps before/during/after an HLO pass, use --xla_dump_pass_re=<pass_name>.

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237510043 by lzc:

Internal Change.

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237469515 by Zhichao Lu:

Parameterize model_builder.build in inputs.py.

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237293511 by rathodv:

Remove multiclass_scores from tensor_dict in transform_data_fn always.

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237260333 by ronnyvotel:

Updating faster_rcnn_meta_arch to define prediction dictionary fields that are batched.

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PiperOrigin-RevId: 247226201

[pkulzc]

Thanks Zhuoran!