google-research

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# coding=utf-8
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# Copyright 2024 The Google Research Authors.
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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#     http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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"""Model definitions for dsprites and 3dident experiments.
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"""
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from absl import flags
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import tensorflow.compat.v2 as tf
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FLAGS = flags.FLAGS
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class LinearLayerOverPretrainedSimclrModel(tf.keras.Model):
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  """Trainable linear evaluation layer over a pretrained SimCLR model.
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  """
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  def __init__(self, path, optimizer, num_classes):
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    super().__init__()
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    self.saved_model = tf.saved_model.load(path)
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    self.dense_layer = tf.keras.layers.Dense(
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        units=num_classes, name='affine_transform')
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    self.optimizer = optimizer
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  def call(self, x):
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    outputs = self.saved_model(x, trainable=False)
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    pred_t = self.dense_layer(outputs['final_avg_pool'])
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    return pred_t
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