| import numpy as np |
| from face_feature.core.leras import nn |
| tf = nn.tf |
|
|
| class Conv2DTranspose(nn.LayerBase): |
| """ |
| use_wscale enables weight scale (equalized learning rate) |
| if kernel_initializer is None, it will be forced to random_normal |
| """ |
| def __init__(self, in_ch, out_ch, kernel_size, strides=2, padding='SAME', use_bias=True, use_wscale=False, kernel_initializer=None, bias_initializer=None, trainable=True, dtype=None, **kwargs ): |
| if not isinstance(strides, int): |
| raise ValueError ("strides must be an int type") |
| kernel_size = int(kernel_size) |
|
|
| if dtype is None: |
| dtype = nn.floatx |
|
|
| self.in_ch = in_ch |
| self.out_ch = out_ch |
| self.kernel_size = kernel_size |
| self.strides = strides |
| self.padding = padding |
| self.use_bias = use_bias |
| self.use_wscale = use_wscale |
| self.kernel_initializer = kernel_initializer |
| self.bias_initializer = bias_initializer |
| self.trainable = trainable |
| self.dtype = dtype |
| super().__init__(**kwargs) |
|
|
| def build_weights(self): |
| kernel_initializer = self.kernel_initializer |
| if self.use_wscale: |
| gain = 1.0 if self.kernel_size == 1 else np.sqrt(2) |
| fan_in = self.kernel_size*self.kernel_size*self.in_ch |
| he_std = gain / np.sqrt(fan_in) |
| self.wscale = tf.constant(he_std, dtype=self.dtype ) |
| if kernel_initializer is None: |
| kernel_initializer = tf.initializers.random_normal(0, 1.0, dtype=self.dtype) |
|
|
| if kernel_initializer is None: |
| kernel_initializer = nn.initializers.ca() |
| self.weight = tf.get_variable("weight", (self.kernel_size,self.kernel_size,self.out_ch,self.in_ch), dtype=self.dtype, initializer=kernel_initializer, trainable=self.trainable ) |
|
|
| if self.use_bias: |
| bias_initializer = self.bias_initializer |
| if bias_initializer is None: |
| bias_initializer = tf.initializers.zeros(dtype=self.dtype) |
|
|
| self.bias = tf.get_variable("bias", (self.out_ch,), dtype=self.dtype, initializer=bias_initializer, trainable=self.trainable ) |
|
|
| def get_weights(self): |
| weights = [self.weight] |
| if self.use_bias: |
| weights += [self.bias] |
| return weights |
|
|
| def forward(self, x): |
| shape = x.shape |
|
|
| if nn.data_format == "NHWC": |
| h,w,c = shape[1], shape[2], shape[3] |
| output_shape = tf.stack ( (tf.shape(x)[0], |
| self.deconv_length(w, self.strides, self.kernel_size, self.padding), |
| self.deconv_length(h, self.strides, self.kernel_size, self.padding), |
| self.out_ch) ) |
|
|
| strides = [1,self.strides,self.strides,1] |
| else: |
| c,h,w = shape[1], shape[2], shape[3] |
| output_shape = tf.stack ( (tf.shape(x)[0], |
| self.out_ch, |
| self.deconv_length(w, self.strides, self.kernel_size, self.padding), |
| self.deconv_length(h, self.strides, self.kernel_size, self.padding), |
| ) ) |
| strides = [1,1,self.strides,self.strides] |
| weight = self.weight |
| if self.use_wscale: |
| weight = weight * self.wscale |
|
|
| x = tf.nn.conv2d_transpose(x, weight, output_shape, strides, padding=self.padding, data_format=nn.data_format) |
|
|
| if self.use_bias: |
| if nn.data_format == "NHWC": |
| bias = tf.reshape (self.bias, (1,1,1,self.out_ch) ) |
| else: |
| bias = tf.reshape (self.bias, (1,self.out_ch,1,1) ) |
| x = tf.add(x, bias) |
| return x |
|
|
| def __str__(self): |
| r = f"{self.__class__.__name__} : in_ch:{self.in_ch} out_ch:{self.out_ch} " |
|
|
| return r |
|
|
| def deconv_length(self, dim_size, stride_size, kernel_size, padding): |
| assert padding in {'SAME', 'VALID', 'FULL'} |
| if dim_size is None: |
| return None |
| if padding == 'VALID': |
| dim_size = dim_size * stride_size + max(kernel_size - stride_size, 0) |
| elif padding == 'FULL': |
| dim_size = dim_size * stride_size - (stride_size + kernel_size - 2) |
| elif padding == 'SAME': |
| dim_size = dim_size * stride_size |
| return dim_size |
| nn.Conv2DTranspose = Conv2DTranspose |