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from core.leras import nn |
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tf = nn.tf |
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class InstanceNorm2D(nn.LayerBase): |
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def __init__(self, in_ch, dtype=None, **kwargs): |
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self.in_ch = in_ch |
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if dtype is None: |
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dtype = nn.floatx |
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self.dtype = dtype |
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super().__init__(**kwargs) |
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def build_weights(self): |
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kernel_initializer = tf.initializers.glorot_uniform(dtype=self.dtype) |
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self.weight = tf.get_variable("weight", (self.in_ch,), dtype=self.dtype, initializer=kernel_initializer ) |
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self.bias = tf.get_variable("bias", (self.in_ch,), dtype=self.dtype, initializer=tf.initializers.zeros() ) |
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def get_weights(self): |
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return [self.weight, self.bias] |
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def forward(self, x): |
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if nn.data_format == "NHWC": |
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shape = (1,1,1,self.in_ch) |
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else: |
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shape = (1,self.in_ch,1,1) |
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weight = tf.reshape ( self.weight , shape ) |
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bias = tf.reshape ( self.bias , shape ) |
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x_mean = tf.reduce_mean(x, axis=nn.conv2d_spatial_axes, keepdims=True ) |
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x_std = tf.math.reduce_std(x, axis=nn.conv2d_spatial_axes, keepdims=True ) + 1e-5 |
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x = (x - x_mean) / x_std |
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x *= weight |
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x += bias |
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return x |
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nn.InstanceNorm2D = InstanceNorm2D |