Files
2022-06-16 15:28:52 +00:00

106 lines
4.1 KiB
Python

import tensorflow as tf
from stylegan2_ae.layers.commons import compute_runtime_coef
from stylegan2_ae.layers.dense import Dense
from stylegan2_ae.layers.bias_act import BiasAct
from stylegan2_ae.layers.cuda.upfirdn_2d_v2 import upsample_conv_2d, conv_downsample_2d, compute_paddings
class ModulatedConv2D(tf.keras.layers.Layer):
def __init__(self, in_res, in_fmaps, fmaps, kernel, up, down, demodulate, resample_kernel, gain, lrmul,
fused_modconv, **kwargs):
super(ModulatedConv2D, self).__init__(**kwargs)
assert not (up and down)
self.in_res = in_res
self.in_fmaps = in_fmaps
self.fmaps = fmaps
self.kernel = kernel
self.demodulate = demodulate
self.up = up
self.down = down
self.fused_modconv = fused_modconv
self.gain = gain
self.lrmul = lrmul
# self.resample_kernel = resample_kernel
self.k, self.pad0, self.pad1 = compute_paddings(resample_kernel, self.kernel, up, down, is_conv=True)
# self.factor = 2
self.mod_dense = Dense(self.in_fmaps, gain=1.0, lrmul=1.0, name='mod_dense')
self.mod_bias = BiasAct(lrmul=1.0, act='linear', name='mod_bias')
def build(self, input_shape):
# x_shape, w_shape = input_shape[0], input_shape[1]
weight_shape = [self.kernel, self.kernel, self.in_fmaps, self.fmaps]
init_std, self.runtime_coef = compute_runtime_coef(weight_shape, self.gain, self.lrmul)
# [kkIO]
w_init = tf.random.normal(shape=weight_shape, mean=0.0, stddev=init_std)
self.w = tf.Variable(w_init, name='w', trainable=True)
def call(self, inputs, training=None, mask=None):
x, y = inputs
# height, width = tf.shape(x)[2], tf.shape(x)[3]
# prepare weights: [BkkIO] Introduce minibatch dimension
w = self.runtime_coef * self.w
ww = w[tf.newaxis]
# Modulate
s = self.mod_dense(y) # [BI]
s = self.mod_bias(s) + 1.0 # [BI]
ww *= s[:, tf.newaxis, tf.newaxis, :, tf.newaxis] # [BkkIO]
if self.demodulate:
d = tf.math.rsqrt(tf.reduce_sum(tf.square(ww), axis=[1, 2, 3]) + 1e-8) # [BO]
ww *= d[:, tf.newaxis, tf.newaxis, tf.newaxis, :] # [BkkIO]
if self.fused_modconv:
# Fused => reshape minibatch to convolution groups
x_shape = tf.shape(x)
ww_shape = tf.shape(ww)
x = tf.reshape(x, [1, -1, x_shape[2], x_shape[3]])
w = tf.reshape(tf.transpose(ww, [1, 2, 3, 0, 4]), [ww_shape[1], ww_shape[2], ww_shape[3], -1])
else:
# [BIhw] Not fused => scale input activations
x *= s[:, :, tf.newaxis, tf.newaxis]
# Convolution with optional up/downsampling.
if self.up:
x = upsample_conv_2d(x, self.in_res, w, self.kernel, self.kernel, self.pad0, self.pad1, self.k)
elif self.down:
x = conv_downsample_2d(x, self.in_res, w, self.kernel, self.kernel, self.pad0, self.pad1, self.k)
else:
x = tf.nn.conv2d(x, w, data_format='NCHW', strides=[1, 1, 1, 1], padding='SAME')
# Reshape/scale output
if self.fused_modconv:
# Fused => reshape convolution groups back to minibatch
x_shape = tf.shape(x)
x = tf.reshape(x, [-1, self.fmaps, x_shape[2], x_shape[3]])
elif self.demodulate:
# [BOhw] Not fused => scale output activations
x *= d[:, :, tf.newaxis, tf.newaxis]
return x
def get_config(self):
config = super(ModulatedConv2D, self).get_config()
config.update({
'in_res': self.in_res,
'in_fmaps': self.in_fmaps,
'fmaps': self.fmaps,
'kernel': self.kernel,
'demodulate': self.demodulate,
'fused_modconv': self.fused_modconv,
'gain': self.gain,
'lrmul': self.lrmul,
'up': self.up,
'down': self.down,
'k': self.k,
'pad0': self.pad0,
'pad1': self.pad1,
'runtime_coef': self.runtime_coef,
})
return config