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55 lines
2.5 KiB
Python
55 lines
2.5 KiB
Python
from keras.engine.topology import Layer, InputSpec
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import keras.utils.conv_utils as conv_utils
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import tensorflow as tf
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import keras.backend as K
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def normalize_data_format(value):
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if value is None:
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value = K.image_data_format()
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data_format = value.lower()
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if data_format not in {'channels_first', 'channels_last'}:
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raise ValueError('The `data_format` argument must be one of '
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'"channels_first", "channels_last". Received: ' +
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str(value))
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return data_format
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class BilinearUpSampling2D(Layer):
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def __init__(self, size=(2, 2), data_format=None, **kwargs):
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super(BilinearUpSampling2D, self).__init__(**kwargs)
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self.data_format = normalize_data_format(data_format)
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self.size = conv_utils.normalize_tuple(size, 2, 'size')
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self.input_spec = InputSpec(ndim=4)
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def compute_output_shape(self, input_shape):
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if self.data_format == 'channels_first':
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height = self.size[0] * input_shape[2] if input_shape[2] is not None else None
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width = self.size[1] * input_shape[3] if input_shape[3] is not None else None
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return (input_shape[0],
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input_shape[1],
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height,
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width)
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elif self.data_format == 'channels_last':
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height = self.size[0] * input_shape[1] if input_shape[1] is not None else None
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width = self.size[1] * input_shape[2] if input_shape[2] is not None else None
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return (input_shape[0],
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height,
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width,
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input_shape[3])
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def call(self, inputs):
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input_shape = K.shape(inputs)
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if self.data_format == 'channels_first':
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height = self.size[0] * input_shape[2] if input_shape[2] is not None else None
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width = self.size[1] * input_shape[3] if input_shape[3] is not None else None
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elif self.data_format == 'channels_last':
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height = self.size[0] * input_shape[1] if input_shape[1] is not None else None
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width = self.size[1] * input_shape[2] if input_shape[2] is not None else None
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return tf.image.resize(inputs, [height, width], method=tf.image.ResizeMethod.BILINEAR)
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def get_config(self):
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config = {'size': self.size, 'data_format': self.data_format}
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base_config = super(BilinearUpSampling2D, self).get_config()
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return dict(list(base_config.items()) + list(config.items()))
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