import numpy as np
from core.leras import nn
tf = nn.tf
class Conv2D(nn.LayerBase):
"""
default kernel_initializer - CA
use_wscale bool enables 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=1, padding='SAME', dilations=1, 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")
if not isinstance(dilations, int):
raise ValueError ("dilations must be an int type")
kernel_size = int(kernel_size)
if dtype is None:
dtype = nn.floatx
if isinstance(padding, str):
if padding == "SAME":
padding = ( (kernel_size - 1) * dilations + 1 ) // 2
elif padding == "VALID":
padding = None
else:
raise ValueError ("Wrong padding type. Should be VALID SAME or INT or 4x INTs")
else:
padding = int(padding)
self.in_ch = in_ch
self.out_ch = out_ch
self.kernel_size = kernel_size
self.strides = strides
self.padding = padding
self.dilations = dilations
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)
self.weight = tf.get_variable("weight", (self.kernel_size,self.kernel_size,self.in_ch,self.out_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):
weight = self.weight
if self.use_wscale:
weight = weight * self.wscale
padding = self.padding
if padding is not None:
if nn.data_format == "NHWC":
padding = [ [0,0], [padding,padding], [padding,padding], [0,0] ]
else:
padding = [ [0,0], [0,0], [padding,padding], [padding,padding] ]
x = tf.pad (x, padding, mode='CONSTANT')
strides = self.strides
if nn.data_format == "NHWC":
strides = [1,strides,strides,1]
else:
strides = [1,1,strides,strides]
dilations = self.dilations
if nn.data_format == "NHWC":
dilations = [1,dilations,dilations,1]
else:
dilations = [1,1,dilations,dilations]
x = tf.nn.conv2d(x, weight, strides, 'VALID', dilations=dilations, 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
nn.Conv2D = Conv2D
