def conv2d(x, w, up=False, down=False, resample_kernel=None, padding=0):
assert not (up and down)
kernel = w.shape[0].value
assert w.shape[1].value == kernel
assert kernel >= 1 and kernel % 2 == 1
w = tf.cast(w, x.dtype)
if up:
x = upsample_conv_2d(x,
w,
data_format='NCHW',
k=resample_kernel,
padding=padding)
elif down:
x = conv_downsample_2d(x,
w,
data_format='NCHW',
k=resample_kernel,
padding=padding)
else:
padding_mode = {0: 'SAME', -(kernel // 2): 'VALID'}[padding]
x = tf.nn.conv2d(x,
w,
data_format='NCHW',
strides=[1, 1, 1, 1],
padding=padding_mode)
return x
def conv2d_layer(x,
fmaps,
kernel,
up=False,
down=False,
resample_kernel=None,
gain=1,
use_wscale=True,
lrmul=1,
weight_var='weight'):
assert not (up and down)
assert kernel >= 1 and kernel % 2 == 1
w = get_weight([kernel, kernel, x.shape[1].value, fmaps],
gain=gain,
use_wscale=use_wscale,
lrmul=lrmul,
weight_var=weight_var)
if up:
x = upsample_conv_2d(x,
tf.cast(w, x.dtype),
data_format='NCHW',
k=resample_kernel)
elif down:
x = conv_downsample_2d(x,
tf.cast(w, x.dtype),
data_format='NCHW',
k=resample_kernel)
else:
x = tf.nn.conv2d(x,
tf.cast(w, x.dtype),
data_format='NCHW',
strides=[1, 1, 1, 1],
padding='SAME')
return x
def modulated_conv2d_layer(x, y, fmaps, kernel, up=False, down=False, demodulate=True, resample_kernel=None, gain=1, use_wscale=True, lrmul=1, fused_modconv=True, weight_var='weight', mod_weight_var='mod_weight', mod_bias_var='mod_bias'):
assert not (up and down)
assert kernel >= 1 and kernel % 2 == 1
# Get weight.
w = get_weight([kernel, kernel, x.shape[1].value, fmaps], gain=gain, use_wscale=use_wscale, lrmul=lrmul, weight_var=weight_var)
ww = w[np.newaxis] # [BkkIO] Introduce minibatch dimension.
## att mask
if not up and not down:
mask = 1 + get_weight([x.shape[2].value, x.shape[3].value], gain=gain, use_wscale=use_wscale, lrmul=lrmul, weight_var='mask')
x = x * mask * tf.rsqrt(tf.reduce_mean(tf.square(mask)) + 1e-8)
# Modulate.
s = dense_layer(y, fmaps=x.shape[1].value, weight_var=mod_weight_var) # [BI] Transform incoming W to style.
s = apply_bias_act(s, bias_var=mod_bias_var) + 1 # [BI] Add bias (initially 1).
ww *= tf.cast(s[:, np.newaxis, np.newaxis, :, np.newaxis], w.dtype) # [BkkIO] Scale input feature maps.
# Demodulate.
if demodulate:
d = tf.rsqrt(tf.reduce_sum(tf.square(ww), axis=[1,2,3]) + 1e-8) # [BO] Scaling factor.
ww *= d[:, np.newaxis, np.newaxis, np.newaxis, :] # [BkkIO] Scale output feature maps.
# Reshape/scale input.
if fused_modconv:
x = tf.reshape(x, [1, -1, x.shape[2], x.shape[3]]) # Fused => reshape minibatch to convolution groups.
w = tf.reshape(tf.transpose(ww, [1, 2, 3, 0, 4]), [ww.shape[1], ww.shape[2], ww.shape[3], -1])
else:
x *= tf.cast(s[:, :, np.newaxis, np.newaxis], x.dtype) # [BIhw] Not fused => scale input activations.
# Convolution with optional up/downsampling.
if up:
x = upsample_conv_2d(x, tf.cast(w, x.dtype), data_format='NCHW', k=resample_kernel)
elif down:
x = conv_downsample_2d(x, tf.cast(w, x.dtype), data_format='NCHW', k=resample_kernel)
else:
x = tf.nn.conv2d(x, tf.cast(w, x.dtype), data_format='NCHW', strides=[1,1,1,1], padding='SAME')
# Reshape/scale output.
if fused_modconv:
x = tf.reshape(x, [-1, fmaps, x.shape[2], x.shape[3]]) # Fused => reshape convolution groups back to minibatch.
elif demodulate:
x *= tf.cast(d[:, :, np.newaxis, np.newaxis], x.dtype) # [BOhw] Not fused => scale output activations.
return x
def decomposition_conv2d_layer(x,
y,
fmaps,
kernel,
up=False,
down=False,
demodulate=True,
resample_kernel=None,
gain=1,
use_wscale=True,
lrmul=1,
fused_modconv=True,
weight_var='weight',
mod_weight_var='U_weight',
mod_bias_var='mod_bias'):
assert not (up and down)
assert kernel >= 1 and kernel % 2 == 1
# Get weight.
out_channel = fmaps
in_channel = kernel * kernel * x.shape[1].value
s_dimension = min(out_channel, in_channel)
U = get_weight([out_channel, s_dimension],
gain=gain,
use_wscale=use_wscale,
lrmul=lrmul,
weight_var='U_' + weight_var)
V = get_weight([in_channel, s_dimension],
gain=gain,
use_wscale=use_wscale,
lrmul=lrmul,
weight_var='V_' + weight_var)
# linear and normalization to obtain the style vector s and its diagnonal matrix S
s = dense_layer(
y, fmaps=s_dimension,
weight_var=mod_weight_var) # [BI] Transform incoming W to style.
s = apply_bias_act(
s, bias_var=mod_bias_var) + 1 # [BI] Add bias (initially 1).
s *= tf.rsqrt(tf.reduce_mean(tf.square(s), axis=1, keepdims=True) + 1e-8)
# construct diagnol matrix using style s
S = tf.matrix_diag(s)
# using S to construct a controllable matrix w
w = tf.matmul(tf.reshape(S, [-1, s_dimension]), tf.transpose(V, [1, 0]))
w = tf.reshape(w, [-1, s_dimension, in_channel])
w = tf.transpose(w, [0, 2, 1])
w = tf.matmul(tf.reshape(w, [-1, s_dimension]), tf.transpose(U, [1, 0]))
w = tf.reshape(w, [-1, kernel, kernel, x.shape[1].value, out_channel])
# normalize w similar to weight demodulation
if demodulate:
d = tf.rsqrt(tf.reduce_sum(tf.square(w), axis=[1, 2, 3]) +
1e-8) # [BO] Scaling factor.
w *= d[:, np.newaxis, np.newaxis,
np.newaxis, :] # [BkkIO] Scale output feature maps.
if fused_modconv:
x = tf.reshape(x,
[1, -1, x.shape[2], x.shape[3]
]) # Fused => reshape minibatch to convolution groups.
w = tf.reshape(tf.transpose(w, [1, 2, 3, 0, 4]),
[w.shape[1], w.shape[2], w.shape[3], -1])
else:
x *= tf.cast(s[:, :, np.newaxis, np.newaxis],
x.dtype) # [BIhw] Not fused => scale input activations.
# Convolution with optional up/downsampling.
if up:
x = upsample_conv_2d(x,
tf.cast(w, x.dtype),
data_format='NCHW',
k=resample_kernel)
elif down:
x = conv_downsample_2d(x,
tf.cast(w, x.dtype),
data_format='NCHW',
k=resample_kernel)
else:
x = tf.nn.conv2d(x,
tf.cast(w, x.dtype),
data_format='NCHW',
strides=[1, 1, 1, 1],
padding='SAME')
if fused_modconv:
x = tf.reshape(
x, [-1, fmaps, x.shape[2], x.shape[3]
]) # Fused => reshape convolution groups back to minibatch.
elif demodulate:
x *= tf.cast(d[:, :, np.newaxis, np.newaxis],
x.dtype) # [BOhw] Not fused => scale output activations.
return x