def process_reals(x, labels, lod, mirror_augment, drange_data, drange_net):
with tf.name_scope('DynamicRange'):
x = tf.cast(x, tf.float32)
x = misc.adjust_dynamic_range(x, drange_data, drange_net)
if mirror_augment:
with tf.name_scope('MirrorAugment'):
x = tf.where(
tf.random_uniform([tf.shape(x)[0]]) < 0.5, x,
tf.reverse(x, [3]))
with tf.name_scope(
'FadeLOD'
): # Smooth crossfade between consecutive levels-of-detail.
s = tf.shape(x)
y = tf.reshape(x, [-1, s[1], s[2] // 2, 2, s[3] // 2, 2])
y = tf.reduce_mean(y, axis=[3, 5], keepdims=True)
y = tf.tile(y, [1, 1, 1, 2, 1, 2])
y = tf.reshape(y, [-1, s[1], s[2], s[3]])
x = tflib.lerp(x, y, lod - tf.floor(lod))
with tf.name_scope(
'UpscaleLOD'
): # Upscale to match the expected input/output size of the networks.
s = tf.shape(x)
factor = tf.cast(2**tf.floor(lod), tf.int32)
x = tf.reshape(x, [-1, s[1], s[2], 1, s[3], 1])
x = tf.tile(x, [1, 1, 1, factor, 1, factor])
x = tf.reshape(x, [-1, s[1], s[2] * factor, s[3] * factor])
return x, labels
def grow(x, res, lod):
y = block(res, x)
img = lambda: upscale2d(torgb(res, y), 2**lod)
img = cset(
img, (lod_in > lod), lambda: upscale2d(
tflib.lerp(torgb(res, y), upscale2d(torgb(res - 1, x)),
lod_in - lod), 2**lod))
if lod > 0:
img = cset(img, (lod_in < lod),
lambda: grow(y, res + 1, lod - 1))
return img()
def grow(res, lod):
x = lambda: fromrgb(downscale2d(images_in, 2**lod), res)
if lod > 0:
x = cset(x, (lod_in < lod), lambda: grow(res + 1, lod - 1))
x = block(x(), res)
y = lambda: x
if res > 2:
y = cset(
y, (lod_in > lod), lambda: tflib.lerp(
x,
fromrgb(downscale2d(images_in, 2**(lod + 1)), res - 1),
lod_in - lod))
return y()
def D_wgan_gp(G,
D,
opt,
training_set,
minibatch_size,
reals,
labels,
wgan_lambda=10.0,
wgan_epsilon=0.001,
wgan_target=1.0):
_ = opt, training_set
latents = tf.random_normal([minibatch_size] + G.input_shapes[0][1:])
fake_images_out = G.get_output_for(latents, labels, is_training=True)
real_scores_out = D.get_output_for(reals, labels, is_training=True)
fake_scores_out = D.get_output_for(fake_images_out,
labels,
is_training=True)
real_scores_out = autosummary('Loss/scores/real', real_scores_out)
fake_scores_out = autosummary('Loss/scores/fake', fake_scores_out)
loss = fake_scores_out - real_scores_out
with tf.name_scope('EpsilonPenalty'):
epsilon_penalty = autosummary('Loss/epsilon_penalty',
tf.square(real_scores_out))
loss += epsilon_penalty * wgan_epsilon
with tf.name_scope('GradientPenalty'):
mixing_factors = tf.random_uniform([minibatch_size, 1, 1, 1],
0.0,
1.0,
dtype=fake_images_out.dtype)
mixed_images_out = tflib.lerp(tf.cast(reals, fake_images_out.dtype),
fake_images_out, mixing_factors)
mixed_scores_out = D.get_output_for(mixed_images_out,
labels,
is_training=True)
mixed_scores_out = autosummary('Loss/scores/mixed', mixed_scores_out)
mixed_grads = tf.gradients(tf.reduce_sum(mixed_scores_out),
[mixed_images_out])[0]
mixed_norms = tf.sqrt(
tf.reduce_sum(tf.square(mixed_grads), axis=[1, 2, 3]))
mixed_norms = autosummary('Loss/mixed_norms', mixed_norms)
gradient_penalty = tf.square(mixed_norms - wgan_target)
reg = gradient_penalty * (wgan_lambda / (wgan_target**2))
return loss, reg
def grow(res, lod):
x = lambda: fromrgb(naive_downsample_2d(images_in, factor=2**lod), res)
if lod > 0: x = cset(x, (lod_in < lod), lambda: grow(res + 1, lod - 1))
x = block(x(), res); y = lambda: x
y = cset(y, (lod_in > lod), lambda: tflib.lerp(x, fromrgb(naive_downsample_2d(images_in, factor=2**(lod+1)), res - 1), lod_in - lod))
return y()
def grow(x, res, lod):
y = block(res, x)
img = lambda: naive_upsample_2d(torgb(res, y), factor=2**lod)
img = cset(img, (lod_in > lod), lambda: naive_upsample_2d(tflib.lerp(torgb(res, y), upsample_2d(torgb(res - 1, x)), lod_in - lod), factor=2**lod))
if lod > 0: img = cset(img, (lod_in < lod), lambda: grow(y, res + 1, lod - 1))
return img()
def G_main(
latents_in, # First input: Latent vectors (Z) [minibatch, latent_size].
labels_in, # Second input: Conditioning labels [minibatch, label_size].
truncation_psi = 0.5, # Style strength multiplier for the truncation trick. None = disable.
truncation_cutoff = None, # Number of layers for which to apply the truncation trick. None = disable.
truncation_psi_val = None, # Value for truncation_psi to use during validation.
truncation_cutoff_val = None, # Value for truncation_cutoff to use during validation.
dlatent_avg_beta = 0.995, # Decay for tracking the moving average of W during training. None = disable.
style_mixing_prob = 0.9, # Probability of mixing styles during training. None = disable.
is_training = False, # Network is under training? Enables and disables specific features.
is_validation = False, # Network is under validation? Chooses which value to use for truncation_psi.
return_dlatents = False, # Return dlatents in addition to the images?
is_template_graph = False, # True = template graph constructed by the Network class, False = actual evaluation.
components = EasyDict(), # Container for sub-networks. Retained between calls.
mapping_func = 'G_mapping', # Build func name for the mapping network.
synthesis_func = 'G_synthesis_stylegan2', # Build func name for the synthesis network.
**kwargs): # Arguments for sub-networks (mapping and synthesis).
# Validate arguments.
assert not is_training or not is_validation
assert isinstance(components, EasyDict)
if is_validation:
truncation_psi = truncation_psi_val
truncation_cutoff = truncation_cutoff_val
if is_training or (truncation_psi is not None and not tflib.is_tf_expression(truncation_psi) and truncation_psi == 1):
truncation_psi = None
if is_training:
truncation_cutoff = None
if not is_training or (dlatent_avg_beta is not None and not tflib.is_tf_expression(dlatent_avg_beta) and dlatent_avg_beta == 1):
dlatent_avg_beta = None
if not is_training or (style_mixing_prob is not None and not tflib.is_tf_expression(style_mixing_prob) and style_mixing_prob <= 0):
style_mixing_prob = None
# Setup components.
if 'synthesis' not in components:
components.synthesis = tflib.Network('G_synthesis', func_name=globals()[synthesis_func], **kwargs)
num_layers = components.synthesis.input_shape[1]
dlatent_size = components.synthesis.input_shape[2]
if 'mapping' not in components:
components.mapping = tflib.Network('G_mapping', func_name=globals()[mapping_func], dlatent_broadcast=num_layers, **kwargs)
# Setup variables.
lod_in = tf.get_variable('lod', initializer=np.float32(0), trainable=False)
dlatent_avg = tf.get_variable('dlatent_avg', shape=[dlatent_size], initializer=tf.initializers.zeros(), trainable=False)
# Evaluate mapping network.
dlatents = components.mapping.get_output_for(latents_in, labels_in, is_training=is_training, **kwargs)
dlatents = tf.cast(dlatents, tf.float32)
# Update moving average of W.
if dlatent_avg_beta is not None:
with tf.variable_scope('DlatentAvg'):
batch_avg = tf.reduce_mean(dlatents[:, 0], axis=0)
update_op = tf.assign(dlatent_avg, tflib.lerp(batch_avg, dlatent_avg, dlatent_avg_beta))
with tf.control_dependencies([update_op]):
dlatents = tf.identity(dlatents)
# Perform style mixing regularization.
if style_mixing_prob is not None:
with tf.variable_scope('StyleMix'):
latents2 = tf.random_normal(tf.shape(latents_in))
dlatents2 = components.mapping.get_output_for(latents2, labels_in, is_training=is_training, **kwargs)
dlatents2 = tf.cast(dlatents2, tf.float32)
layer_idx = np.arange(num_layers)[np.newaxis, :, np.newaxis]
cur_layers = num_layers - tf.cast(lod_in, tf.int32) * 2
mixing_cutoff = tf.cond(
tf.random_uniform([], 0.0, 1.0) < style_mixing_prob,
lambda: tf.random_uniform([], 1, cur_layers, dtype=tf.int32),
lambda: cur_layers)
dlatents = tf.where(tf.broadcast_to(layer_idx < mixing_cutoff, tf.shape(dlatents)), dlatents, dlatents2)
# Apply truncation trick.
if truncation_psi is not None:
with tf.variable_scope('Truncation'):
layer_idx = np.arange(num_layers)[np.newaxis, :, np.newaxis]
layer_psi = np.ones(layer_idx.shape, dtype=np.float32)
if truncation_cutoff is None:
layer_psi *= truncation_psi
else:
layer_psi = tf.where(layer_idx < truncation_cutoff, layer_psi * truncation_psi, layer_psi)
dlatents = tflib.lerp(dlatent_avg, dlatents, layer_psi)
# Evaluate synthesis network.
deps = []
if 'lod' in components.synthesis.vars:
deps.append(tf.assign(components.synthesis.vars['lod'], lod_in))
with tf.control_dependencies(deps):
images_out = components.synthesis.get_output_for(dlatents, is_training=is_training, force_clean_graph=is_template_graph, **kwargs)
# Return requested outputs.
images_out = tf.identity(images_out, name='images_out')
if return_dlatents:
return images_out, dlatents
return images_out
def _evaluate(self, Gs, Gs_kwargs, num_gpus):
Gs_kwargs = dict(Gs_kwargs)
Gs_kwargs.update(self.Gs_overrides)
minibatch_size = num_gpus * self.minibatch_per_gpu
# Construct TensorFlow graph.
distance_expr = []
for gpu_idx in range(num_gpus):
with tf.device('/gpu:%d' % gpu_idx):
Gs_clone = Gs.clone()
noise_vars = [
var for name, var in
Gs_clone.components.synthesis.vars.items()
if name.startswith('noise')
]
# Generate random latents and interpolation t-values.
lat_t01 = tf.random_normal([self.minibatch_per_gpu * 2] +
Gs_clone.input_shape[1:])
lerp_t = tf.random_uniform(
[self.minibatch_per_gpu], 0.0,
1.0 if self.sampling == 'full' else 0.0)
labels = tf.reshape(
tf.tile(self._get_random_labels_tf(self.minibatch_per_gpu),
[1, 2]), [self.minibatch_per_gpu * 2, -1])
# Interpolate in W or Z.
if self.space == 'w':
dlat_t01 = Gs_clone.components.mapping.get_output_for(
lat_t01, labels, **Gs_kwargs)
dlat_t01 = tf.cast(dlat_t01, tf.float32)
dlat_t0, dlat_t1 = dlat_t01[0::2], dlat_t01[1::2]
dlat_e0 = tflib.lerp(dlat_t0, dlat_t1,
lerp_t[:, np.newaxis, np.newaxis])
dlat_e1 = tflib.lerp(
dlat_t0, dlat_t1,
lerp_t[:, np.newaxis, np.newaxis] + self.epsilon)
dlat_e01 = tf.reshape(tf.stack([dlat_e0, dlat_e1], axis=1),
dlat_t01.shape)
else: # space == 'z'
lat_t0, lat_t1 = lat_t01[0::2], lat_t01[1::2]
lat_e0 = slerp(lat_t0, lat_t1, lerp_t[:, np.newaxis])
lat_e1 = slerp(lat_t0, lat_t1,
lerp_t[:, np.newaxis] + self.epsilon)
lat_e01 = tf.reshape(tf.stack([lat_e0, lat_e1], axis=1),
lat_t01.shape)
dlat_e01 = Gs_clone.components.mapping.get_output_for(
lat_e01, labels, **Gs_kwargs)
# Synthesize images.
with tf.control_dependencies([
var.initializer for var in noise_vars
]): # use same noise inputs for the entire minibatch
images = Gs_clone.components.synthesis.get_output_for(
dlat_e01, randomize_noise=False, **Gs_kwargs)
images = tf.cast(images, tf.float32)
# Crop only the face region.
if self.crop:
c = int(images.shape[2] // 8)
images = images[:, :, c * 3:c * 7, c * 2:c * 6]
# Downsample image to 256x256 if it's larger than that. VGG was built for 224x224 images.
factor = images.shape[2] // 256
if factor > 1:
images = tf.reshape(images, [
-1, images.shape[1], images.shape[2] // factor, factor,
images.shape[3] // factor, factor
])
images = tf.reduce_mean(images, axis=[3, 5])
# Scale dynamic range from [-1,1] to [0,255] for VGG.
images = (images + 1) * (255 / 2)
# Evaluate perceptual distance.
img_e0, img_e1 = images[0::2], images[1::2]
distance_measure = misc.load_pkl(
'http://d36zk2xti64re0.cloudfront.net/stylegan1/networks/metrics/vgg16_zhang_perceptual.pkl'
)
distance_expr.append(
distance_measure.get_output_for(img_e0, img_e1) *
(1 / self.epsilon**2))
# Sampling loop.
all_distances = []
for begin in range(0, self.num_samples, minibatch_size):
self._report_progress(begin, self.num_samples)
all_distances += tflib.run(distance_expr)
all_distances = np.concatenate(all_distances, axis=0)
# Reject outliers.
lo = np.percentile(all_distances, 1, interpolation='lower')
hi = np.percentile(all_distances, 99, interpolation='higher')
filtered_distances = np.extract(
np.logical_and(lo <= all_distances, all_distances <= hi),
all_distances)
self._report_result(np.mean(filtered_distances))