#!/usr/bin/env python
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# Copyright 2024 Brainchip Holdings Ltd.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
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# Unless required by applicable law or agreed to in writing, software
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"""
Utils for VOC and Widerface datasets.
"""
__all__ = ["Coord", "remove_empty_objects", "get_dataset_length"]
import tensorflow as tf
[docs]class Coord:
"""
Static class representing bounding box coordinates.
These values align with the TensorFlow Datasets (tfds) bounding box format.
In tfds, the "bbox" feature is formatted as :
tfds.features.BBox(ymin / height, xmin / width, ymax / height, xmax / width).
"""
x1 = 1
x2 = 3
y1 = 0
y2 = 2
[docs]def remove_empty_objects(sample):
"""
Remove samples with empty objects.
Args:
sample (dict): A dictionary representing a sample with object information.
{'image', 'objects': {'bbox', 'label'}}.
Returns:
tf.Tensor: A boolean tensor indicating whether the sample has non-empty objects.
"""
is_empty = tf.reduce_all(tf.equal(tf.shape(sample['objects']['bbox'])[0], 0))
return tf.math.logical_not(is_empty)
[docs]def get_dataset_length(dataset):
"""
Get the length of a TF dataset.
Args:
dataset (tf.data.Dataset): A TF dataset containing elements.
Returns:
int: The number of elements in the dataset.
"""
count = 0
for _ in dataset:
count += 1
return count