def lsgan_loss(real, weight, fake=None):
if fake:
loss = weight * F.mean(F.squared_error(F.constant(1, real.shape), real)
+ F.pow_scalar(fake, 2))
else:
loss = weight * \
F.mean(F.squared_error(F.constant(1, real.shape), real))
return loss
def create_network(batchsize, imheight, imwidth, args, seen):
import gc
gc.collect()
nnabla_ext.cuda.clear_memory_cache()
anchors = args.num_anchors
classes = args.num_classes
yolo_x = nn.Variable((batchsize, 3, imheight, imwidth))
target = nn.Variable((batchsize, 50 * 5))
yolo_features = yolov2.yolov2(yolo_x, anchors, classes, test=False)
nB = yolo_features.shape[0]
nA = args.num_anchors
nC = args.num_classes
nH = yolo_features.shape[2]
nW = yolo_features.shape[3]
# Bouding box regression loss
# pred.shape = [nB, nA, 4, nH, nW]
output = F.reshape(yolo_features, (nB, nA, (5 + nC), nH, nW))
xy = F.sigmoid(output[:, :, :2, ...])
wh = output[:, :, 2:4, ...]
bbox_pred = F.concatenate(xy, wh, axis=2)
conf_pred = F.sigmoid(output[:, :, 4:5, ...])
cls_pred = output[:, :, 5:, ...]
region_loss_targets = RegionLossTargets(nC, args.anchors, seen,
args.coord_scale,
args.noobject_scale,
args.object_scale,
args.class_scale, args.thresh)
tcoord, mcoord, tconf, mconf, tcls, mcls = region_loss_targets(
bbox_pred, target)
for v in tcoord, mcoord, tconf, mconf, tcls, mcls:
v.need_grad = False
# Bounding box regression
bbox_loss = F.sum(F.squared_error(bbox_pred, tcoord) * mcoord)
# Conf (IoU) regression loss
conf_loss = F.sum(F.squared_error(conf_pred, tconf) * mconf)
# Class probability regression loss
cls_loss = F.sum(F.softmax_cross_entropy(cls_pred, tcls, axis=2) * mcls)
# Note:
# loss is devided by 2.0 due to the fact that the original darknet
# code doesn't multiply the derivative of square functions by 2.0
# in region_layer.c.
loss = (bbox_loss + conf_loss) / 2.0 + cls_loss
return yolo_x, target, loss, region_loss_targets
def ls_gan_loss(r_out, f_out):
# todo: set constant arbitrary
# D
d_gan_real = F.mean(F.squared_error(r_out,
F.constant(1., shape=r_out.shape)))
d_gan_fake = F.mean(F.squared_error(f_out,
F.constant(0., shape=f_out.shape)))
# G
g_gan = F.mean(F.squared_error(f_out,
F.constant(1., shape=f_out.shape)))
return d_gan_real, d_gan_fake, g_gan
def sigma_regularization(ctx, log_var, one):
with nn.context_scope(ctx):
h = F.exp(log_var)
h = F.pow_scalar(h, 0.5)
h = F.mean(h, axis=1)
r = F.mean(F.squared_error(h, one))
return r
def sigma_regularization(ctx, log_var, one):
with nn.context_scope(ctx):
h = F.exp(log_var)
h = F.pow_scalar(h, 0.5)
b = log_var.shape[0]
r = F.sum(F.squared_error(h, one)) / b
return r
def test_simple_loop():
nn.clear_parameters()
x = nn.Variable.from_numpy_array(np.random.randn(10, 3, 128, 128))
t = nn.Variable.from_numpy_array(np.random.randint(0, 100, (10, )))
unet = UNet(num_classes=1,
model_channels=128,
output_channels=3,
num_res_blocks=2,
attention_resolutions=(16, 8),
attention_num_heads=4,
channel_mult=(1, 1, 2, 2, 4, 4))
y = unet(x, t)
loss = F.mean(F.squared_error(y, x))
import nnabla.solvers as S
solver = S.Sgd()
solver.set_parameters(nn.get_parameters())
from tqdm import trange
tr = trange(100)
for i in tr:
loss.forward(clear_no_need_grad=True)
solver.zero_grad()
loss.backward(clear_buffer=True)
solver.update()
tr.set_description(f"diff: {loss.d.copy():.5f}")
def sr_loss_with_uncertainty(ctx, pred0, pred1, log_var):
#TODO: squared error/absolute error
with nn.context_scope(ctx):
loss_sr = F.mean(F.squared_error(
F.softmax(pred0), F.softmax(pred1)) * F.exp(-log_var)) \
+ F.mean(log_var)
return loss_sr
def capsule_loss(v_norm, t_onehot, recon=None, x=None, m_pos=0.9, m_neg=0.1, wn=0.5, wr=0.0005):
'''
Compute a margin loss given a length vector of output capsules and one-hot labels, and.optionally comptues a reconstruction loss.
Margin loss is given in eq 4. Reconstruction loss is given in Sec 4.1.
Args:
v_norm (nnabla.Variable): A length vector of capsules. A shape of [B, capsules].
t_onehot (nnabla.Variable): A shape of [B, capsules].
recon (nnabla.Variable): Reconstruction output with a shape of [B, 1, 28, 28]. The values are in [0, 0.1].
x (nnabla.Variable): Reconstruction target (i.e. input) with a shape of [B, 1, 28, 28]. The values are in [0, 0.1].
m_pos (float): Margin of capsules corresponding targets.
m_neg (float): Margin of capsules corresponding non-targets.
wn (float): Weight of the non-target margin loss.
wr (float): Weight of the reconstruction loss.
Returns:
nnabla.Variable: 0-dim
'''
# Classification loss
lp = F.sum(t_onehot * F.relu(m_pos - v_norm) ** 2)
ln = F.sum((1 - t_onehot) * F.relu(v_norm - m_neg) ** 2)
lmargin = lp + wn * ln
if recon is None or x is None:
return lmargin / v_norm.shape[0]
# Reconstruction loss
lr = F.sum(F.squared_error(recon, x))
# return (lmargin + wr * lr) / v_norm.shape[0]
lmargin = lmargin / v_norm.shape[0]
lmargin.persistent = True
lreconst = (wr * lr) / v_norm.shape[0]
lreconst.persistent = True
return lmargin, lreconst, lmargin + lreconst
def sigma_regularization(ctx, log_var, one):
with nn.context_scope(ctx):
h = F.exp(log_var)
h = F.pow_scalar(h, 0.5)
b = log_var.shape[0]
r = F.sum(F.squared_error(h, one)) / b
return r
def siamese_loss(e0, e1, t, margin=1.0, eps=1e-4):
dist = F.sum(F.squared_error(e0, e1), axis=1) # Squared distance
# Contrastive loss
sim_cost = t * dist
dissim_cost = (1 - t) * (F.maximum_scalar(margin -
(dist + eps)**(0.5), 0)**2)
return F.mean(sim_cost + dissim_cost)
def sigma_regularization(ctx, log_var, one):
with nn.context_scope(ctx):
h = F.exp(log_var)
h = F.pow_scalar(h, 0.5)
h = F.mean(h, axis=1)
r = F.mean(F.squared_error(h, one))
return r
def create_network(batchsize, imheight, imwidth, args):
import gc
gc.collect()
nnabla_ext.cuda.clear_memory_cache()
anchors = args.num_anchors
classes = args.num_classes
yolo_x = nn.Variable((batchsize, 3, imheight, imwidth))
yolo_features = yolov2.yolov2(yolo_x, anchors, classes, test=False)
nB = yolo_features.shape[0]
nA = args.num_anchors
nC = args.num_classes
nH = yolo_features.shape[2]
nW = yolo_features.shape[3]
output = yolo_features.get_unlinked_variable(need_grad=True)
# TODO: Workaround until v1.0.2.
# Explicitly enable grad since need_grad option above didn't work.
output.need_grad = True
output = F.reshape(output, (nB, nA, (5 + nC), nH, nW))
output_splitted = F.split(output, 2)
x, y, w, h, conf = [v.reshape((nB, nA, nH, nW))
for v in output_splitted[0:5]]
x, y, conf = map(F.sigmoid, [x, y, conf])
cls = F.stack(*output_splitted[5:], axis=2)
cls = cls.reshape((nB*nA, nC, nH*nW))
cls = F.transpose(cls, [0, 2, 1]).reshape((nB*nA*nH*nW, nC))
tx, ty, tw, th, tconf, coord_mask, conf_mask_sq = [
nn.Variable(v.shape) for v in [x, y, w, h, conf, x, conf]]
cls_ones, cls_mask = [nn.Variable(cls.shape) for _ in range(2)]
tcls, cls_mask_bb = [nn.Variable((cls.shape[0], 1)) for _ in range(2)]
coord_mask_sq = F.pow_scalar(coord_mask, 2)
loss_x = args.coord_scale * F.sum(F.squared_error(x, tx) * coord_mask_sq)
loss_y = args.coord_scale * F.sum(F.squared_error(y, ty) * coord_mask_sq)
loss_w = args.coord_scale * F.sum(F.squared_error(w, tw) * coord_mask_sq)
loss_h = args.coord_scale * F.sum(F.squared_error(h, th) * coord_mask_sq)
loss_conf = F.sum(F.squared_error(conf, tconf) * conf_mask_sq)
loss_cls = args.class_scale * \
F.sum(cls_mask_bb * F.softmax_cross_entropy(cls + cls_ones - cls_mask, tcls))
loss_nnabla = loss_x + loss_y + loss_w + loss_h + loss_conf + loss_cls
return yolo_x, yolo_features, (x, y, w, h, conf, cls), (tx, ty, tw, th, tconf, coord_mask, conf_mask_sq, cls_ones, cls_mask, tcls, cls_mask_bb), loss_nnabla
def _build(self):
# inference
self.infer_obs_t = nn.Variable((1,) + self.obs_shape)
with nn.parameter_scope('trainable'):
self.infer_policy_t = policy_network(self.infer_obs_t,
self.action_size, 'actor')
# training
self.obss_t = nn.Variable((self.batch_size,) + self.obs_shape)
self.acts_t = nn.Variable((self.batch_size, self.action_size))
self.rews_tp1 = nn.Variable((self.batch_size, 1))
self.obss_tp1 = nn.Variable((self.batch_size,) + self.obs_shape)
self.ters_tp1 = nn.Variable((self.batch_size, 1))
# critic training
with nn.parameter_scope('trainable'):
q_t = q_network(self.obss_t, self.acts_t, 'critic')
with nn.parameter_scope('target'):
policy_tp1 = policy_network(self.obss_tp1, self.action_size,
'actor')
q_tp1 = q_network(self.obss_tp1, policy_tp1, 'critic')
y = self.rews_tp1 + self.gamma * q_tp1 * (1.0 - self.ters_tp1)
self.critic_loss = F.mean(F.squared_error(q_t, y))
# actor training
with nn.parameter_scope('trainable'):
policy_t = policy_network(self.obss_t, self.action_size, 'actor')
q_t_with_actor = q_network(self.obss_t, policy_t, 'critic')
self.actor_loss = -F.mean(q_t_with_actor)
# get neural network parameters
with nn.parameter_scope('trainable'):
with nn.parameter_scope('critic'):
critic_params = nn.get_parameters()
with nn.parameter_scope('actor'):
actor_params = nn.get_parameters()
# setup optimizers
self.critic_solver = S.Adam(self.critic_lr)
self.critic_solver.set_parameters(critic_params)
self.actor_solver = S.Adam(self.actor_lr)
self.actor_solver.set_parameters(actor_params)
with nn.parameter_scope('trainable'):
trainable_params = nn.get_parameters()
with nn.parameter_scope('target'):
target_params = nn.get_parameters()
# build target update
update_targets = []
sync_targets = []
for key, src in trainable_params.items():
dst = target_params[key]
updated_dst = (1.0 - self.tau) * dst + self.tau * src
update_targets.append(F.assign(dst, updated_dst))
sync_targets.append(F.assign(dst, src))
self.update_target_expr = F.sink(*update_targets)
self.sync_target_expr = F.sink(*sync_targets)
def mnist_lenet_siamese(x0, x1, test=False):
""""""
h0 = mnist_lenet_feature(x0, test)
h1 = mnist_lenet_feature(x1, test) # share weights
# h = (h0 - h1) ** 2 # equivalent
h = F.squared_error(h0, h1)
p = F.sum(h, axis=1)
return p
def mnist_lenet_siamese(x0, x1, test=False):
""""""
h0 = mnist_lenet_feature(x0, test)
h1 = mnist_lenet_feature(x1, test) # share weights
# h = (h0 - h1) ** 2 # equivalent
h = F.squared_error(h0, h1)
p = F.sum(h, axis=1)
return p
def feature_matching_loss(x, y, num=4):
"""
Calculate feature matching loss
"""
fm_loss = 0.0
for i in range(num):
fm_loss += F.mean(F.squared_error(x[i], y[i]))
return fm_loss
def sigmas_regularization(ctx, log_var0, log_var1):
with nn.context_scope(ctx):
h0 = F.exp(log_var0)
h0 = F.pow_scalar(h0, 0.5)
h1 = F.exp(log_var1)
h1 = F.pow_scalar(h1, 0.5)
r = F.mean(F.squared_error(h0, h1))
return r
def sr_loss_with_uncertainty(ctx, pred0, pred1, log_var0, log_var1):
#TODO: squared error/absolute error
s0 = F.exp(log_var0)
s1 = F.exp(log_var1)
squared_error = F.squared_error(pred0, pred1)
with nn.context_scope(ctx):
loss_sr = F.mean(squared_error * (1 / s0 + 1 / s1) + (s0 / s1 + s1 / s0)) * 0.5
return loss_sr
def sigmas_regularization(ctx, log_var0, log_var1):
with nn.context_scope(ctx):
h0 = F.exp(log_var0)
h0 = F.pow_scalar(h0, 0.5)
h1 = F.exp(log_var1)
h1 = F.pow_scalar(h1, 0.5)
r = F.mean(F.squared_error(h0, h1))
return r
def sr_loss_with_uncertainty(ctx, pred0, pred1, log_var0, log_var1):
#TODO: squared error/absolute error
s0 = F.exp(log_var0)
s1 = F.exp(log_var1)
squared_error = F.squared_error(pred0, pred1)
with nn.context_scope(ctx):
loss_sr = F.mean(squared_error * (1 / s0 + 1 / s1) + (s0 / s1 + s1 / s0)) * 0.5
return loss_sr
def sr_loss_with_uncertainty(ctx, pred0, pred1, log_var0, log_var1):
var0 = F.exp(log_var0)
var1 = F.exp(log_var1)
s0 = F.pow_scalar(var0, 0.5)
s1 = F.pow_scalar(var0, 0.5)
squared_error = F.squared_error(pred0, pred1)
with nn.context_scope(ctx):
loss = F.log(s1/s0) + (var0/var1 + squared_error/var1) * 0.5
loss_sr = F.mean(loss)
return loss_sr
def __call__(self, x, return_encoding_indices=False):
x = F.transpose(x, (0, 2, 3, 1))
x_flat = x.reshape((-1, self.embedding_dim))
x_flat_squared = F.broadcast(F.sum(x_flat**2, axis=1, keepdims=True),
(x_flat.shape[0], self.num_embedding))
emb_wt_squared = F.transpose(
F.sum(self.embedding_weight**2, axis=1, keepdims=True), (1, 0))
distances = x_flat_squared + emb_wt_squared - 2 * \
F.affine(x_flat, F.transpose(self.embedding_weight, (1, 0)))
encoding_indices = F.min(distances,
only_index=True,
axis=1,
keepdims=True)
encoding_indices.need_grad = False
quantized = F.embed(
encoding_indices.reshape(encoding_indices.shape[:-1]),
self.embedding_weight).reshape(x.shape)
if return_encoding_indices:
return encoding_indices, F.transpose(quantized, (0, 3, 1, 2))
encodings = F.one_hot(encoding_indices, (self.num_embedding, ))
e_latent_loss = F.mean(
F.squared_error(quantized.get_unlinked_variable(need_grad=False),
x))
q_latent_loss = F.mean(
F.squared_error(quantized,
x.get_unlinked_variable(need_grad=False)))
loss = q_latent_loss + self.commitment_cost * e_latent_loss
quantized = x + (quantized - x).get_unlinked_variable(need_grad=False)
avg_probs = F.mean(encodings, axis=0)
perplexity = F.exp(-F.sum(avg_probs * F.log(avg_probs + 1.0e-10)))
return loss, F.transpose(quantized,
(0, 3, 1, 2)), perplexity, encodings
def sr_loss_with_uncertainty(ctx, pred0, pred1, log_v0, log_v1,
log_s0, log_s1):
v0 = F.exp(log_v0)
v1 = F.exp(log_v1)
squared_error = F.squared_error(pred0, pred1)
s0 = F.exp(log_s0)
s1 = F.exp(log_s1)
with nn.context_scope(ctx):
error = squared_error * (1 / v0 + 1 / v1) + (v0 / v1 + v1 / v0) + (s0 / s1 + s1 / s0)
loss_sr = F.mean(error) * 0.5
return loss_sr
def preservation_loss(self, x, target):
r"""Returns content preservation loss.
Args:
x (nn.Variable): Input variable.
target (nn.Variable): Target variable.
Returns:
nn.Variable: Output loss.
"""
loss = F.mean(F.squared_error(x, target))
return loss
def sr_loss_with_uncertainty(ctx, pred0, pred1, log_v0, log_v1, log_s0,
log_s1):
v0 = F.exp(log_v0)
v1 = F.exp(log_v1)
squared_error = F.squared_error(pred0, pred1)
s0 = F.exp(log_s0)
s1 = F.exp(log_s1)
with nn.context_scope(ctx):
error = squared_error * (1 / v0 + 1 / v1) + (v0 / v1 + v1 / v0) + (
s0 / s1 + s1 / s0)
loss_sr = F.mean(error) * 0.5
return loss_sr
def mse(x, y, mask=None, eps=1e-5):
# l2 distance and reduce mean
se = F.squared_error(x, y)
if mask is not None:
assert se.shape[:2] == mask.shape[:2]
se *= F.reshape(mask, se.shape)
return F.sum(se) / (F.sum(mask) + eps)
return F.mean(se)
def train(self):
# variables for training
tx_in = nn.Variable(
[self._batch_size, self._x_input_length, self._cols_size])
tx_out = nn.Variable(
[self._batch_size, self._x_output_length, self._cols_size])
tpred = self.network(tx_in, self._lstm_unit_name, self._lstm_units)
tpred.persistent = True
loss = F.mean(F.squared_error(tpred, tx_out))
solver = S.Adam(self._learning_rate)
solver.set_parameters(nn.get_parameters())
# variables for validation
vx_in = nn.Variable(
[self._batch_size, self._x_input_length, self._cols_size])
vx_out = nn.Variable(
[self._batch_size, self._x_output_length, self._cols_size])
vpred = self.network(vx_in, self._lstm_unit_name, self._lstm_units)
# data iterators
tdata = self._load_dataset(self._training_dataset_path,
self._batch_size,
shuffle=True)
vdata = self._load_dataset(self._validation_dataset_path,
self._batch_size,
shuffle=True)
# monitors
from nnabla.monitor import Monitor, MonitorSeries, MonitorTimeElapsed
monitor = Monitor(self._monitor_path)
monitor_loss = MonitorSeries("Training loss", monitor, interval=10)
monitor_err = MonitorSeries("Training error", monitor, interval=10)
monitor_time = MonitorTimeElapsed("Training time",
monitor,
interval=100)
monitor_verr = MonitorSeries("Validation error", monitor, interval=10)
# Training loop
for i in range(self._max_iter):
if i % self._val_interval == 0:
ve = self._validate(vpred, vx_in, vx_out, vdata,
self._val_iter)
monitor_verr.add(i, ve / self._val_iter)
te = self._train(tpred, solver, loss, tx_in, tx_out, tdata.next(),
self._weight_decay)
monitor_loss.add(i, loss.d.copy())
monitor_err.add(i, te)
monitor_time.add(i)
ve = self._validate(vpred, vx_in, vx_out, vdata, self._val_iter)
monitor_verr.add(i, ve / self._val_iter)
# Save a best model parameters
nn.save_parameters(self._model_params_path)
def spectral_loss(self, x, target):
r"""Returns the multi-scale spectral loss.
Args:
x (nn.Variable): Input variable.
target (nn.Variable): Target variable.
Returns:
nn.Variable: Multi-scale spectral loss.
"""
loss = []
for window_size in self.hp.window_sizes:
sx = log_mel_spectrogram(x, self.hp.sr, window_size)
st = log_mel_spectrogram(target, self.hp.sr, window_size)
st.need_grad = False # avoid grads flowing though targets
loss.append(F.mean(F.squared_error(sx, st)))
return sum(loss)
def get_warp_loss(conf, rnn_length, frame_t, frame_t_pre, flow_lr):
"""
Warp loss
"""
input_frames = F.reshape(frame_t,
(conf.train.batch_size * (rnn_length - 1),
conf.train.crop_size, conf.train.crop_size, 3))
frame_t_pre_reshaped = F.reshape(
frame_t_pre,
(conf.train.batch_size *
(rnn_length - 1), conf.train.crop_size, conf.train.crop_size, 3))
s_input_warp = warp_by_flow(frame_t_pre_reshaped, flow_lr)
warp_loss = F.mean(
F.sum(F.squared_error(input_frames, s_input_warp), axis=[3]))
return warp_loss
def sr_loss_with_uncertainty_and_coef(ctx, pred0, pred1, log_var0, log_var1):
c0 = srwu_learned_coef(ctx, log_var0)
c1 = srwu_learned_coef(ctx, log_var1)
sc0 = sigmas_learned_coef(ctx, log_var0, log_var1)
sc1 = sigmas_learned_coef(ctx, log_var1, log_var0)
c0.need_grad = False
c1.need_grad = False
sc0.need_grad = False
sc1.need_grad = False
#TODO: squared error/absolute error
s0 = F.exp(log_var0)
s1 = F.exp(log_var1)
squared_error = F.squared_error(pred0, pred1)
with nn.context_scope(ctx):
loss_sr = F.mean(
squared_error * (c0 / s0 + c1 / s1) + (sc0 * s0 / s1 + sc1 * s1 / s0)) * 0.5
return loss_sr
def _build(self):
generator_fn, discriminator_fn = self._network_funcs()
# real shape
ch, w, h = self.real.shape[1:]
# inputs
self.x = nn.Variable((1, ch, w, h))
self.y = nn.Variable((1, ch, w, h))
self.rec_x = nn.Variable((1, ch, w, h))
self.rec_y = nn.Variable((1, ch, w, h))
y_real = nn.Variable.from_numpy_array(self.real)
y_real.persistent = True
# padding inputs
padded_x = _pad(self.x, self.kernel, self.num_layer)
padded_rec_x = _pad(self.rec_x, self.kernel, self.num_layer)
# generate fake image
self.fake = generator_fn(x=padded_x, y=self.y)
fake_without_grads = F.identity(self.fake)
fake_without_grads.need_grad = False
rec = generator_fn(x=padded_rec_x, y=self.rec_y)
# discriminate images
p_real = discriminator_fn(x=y_real)
p_fake = discriminator_fn(x=self.fake)
p_fake_without_grads = discriminator_fn(x=fake_without_grads)
# gradient penalty for discriminator
grad_penalty = _calc_gradient_penalty(y_real, fake_without_grads,
discriminator_fn)
# discriminator loss
self.d_real_error = -F.mean(p_real)
self.d_fake_error = F.mean(p_fake_without_grads)
self.d_error = self.d_real_error + self.d_fake_error \
+ self.lam_grad * grad_penalty
# generator loss
self.rec_error = F.mean(F.squared_error(rec, y_real))
self.g_fake_error = -F.mean(p_fake)
self.g_error = self.g_fake_error + self.alpha_recon * self.rec_error
def __init__(self, num_actions, num_envs, batch_size, v_coeff, ent_coeff,
lr_scheduler):
# inference graph
self.infer_obs_t = nn.Variable((num_envs, 4, 84, 84))
self.infer_pi_t,\
self.infer_value_t = cnn_network(self.infer_obs_t, num_actions,
'network')
self.infer_t = F.sink(self.infer_pi_t, self.infer_value_t)
# evaluation graph
self.eval_obs_t = nn.Variable((1, 4, 84, 84))
self.eval_pi_t, _ = cnn_network(self.eval_obs_t, num_actions,
'network')
# training graph
self.obss_t = nn.Variable((batch_size, 4, 84, 84))
self.acts_t = nn.Variable((batch_size, 1))
self.rets_t = nn.Variable((batch_size, 1))
self.advs_t = nn.Variable((batch_size, 1))
pi_t, value_t = cnn_network(self.obss_t, num_actions, 'network')
# value loss
l2loss = F.squared_error(value_t, self.rets_t)
self.value_loss = v_coeff * F.mean(l2loss)
# policy loss
log_pi_t = F.log(pi_t + 1e-20)
a_one_hot = F.one_hot(self.acts_t, (num_actions, ))
log_probs_t = F.sum(log_pi_t * a_one_hot, axis=1, keepdims=True)
self.pi_loss = F.mean(log_probs_t * self.advs_t)
# KL loss
entropy = -ent_coeff * F.mean(F.sum(pi_t * log_pi_t, axis=1))
self.loss = self.value_loss - self.pi_loss - entropy
self.params = nn.get_parameters()
self.solver = S.RMSprop(lr_scheduler(0.0), 0.99, 1e-5)
self.solver.set_parameters(self.params)
self.lr_scheduler = lr_scheduler
def vgg16_perceptual_loss(fake, real):
'''
VGG perceptual loss based on VGG-16 network.
Assuming the values in fake and real are in [0, 255].
'''
from nnabla.models.imagenet import VGG16
class VisitFeatures(object):
def __init__(self):
self.features = []
self.relu_counter = 0
# self.features_at = set([1, 4, 7, 10]) : ['relu1_2', 'relu2_2', 'relu3_3', 'relu4_3']
self.features_at = set([4, 7])
def __call__(self, f):
if not f.name.startswith('ReLU'):
return
if self.relu_counter in self.features_at:
self.features.append(f.outputs[0])
self.relu_counter += 1
vgg = VGG16()
def get_features(x):
o = vgg(x, use_up_to='lastconv')
f = VisitFeatures()
o.visit(f)
return f
with nn.parameter_scope("vgg16_loss"):
fake_features = get_features(fake)
real_features = get_features(real)
return sum([
F.mean(F.squared_error(ff, fr))
for ff, fr in zip(fake_features.features, real_features.features)
])
def sr_loss(ctx, pred0, pred1):
with nn.context_scope(ctx):
pred_x_u0 = F.softmax(pred0)
pred_x_u1 = F.softmax(pred1)
loss_sr = F.mean(F.squared_error(pred_x_u0, pred_x_u1))
return loss_sr
def sr_loss(ctx, pred0, pred1):
with nn.context_scope(ctx):
loss_sr = F.mean(F.squared_error(pred0, pred1))
return loss_sr
def sr_loss(ctx, pred0, pred1):
with nn.context_scope(ctx):
loss_sr = F.mean(F.squared_error(pred0, pred1))
return loss_sr
def train(args):
"""
Main script.
"""
# Get context.
from nnabla.contrib.context import extension_context
extension_module = args.context
if args.context is None:
extension_module = 'cpu'
logger.info("Running in %s" % extension_module)
ctx = extension_context(extension_module, device_id=args.device_id)
nn.set_default_context(ctx)
# Create CNN network for both training and testing.
# TRAIN
# Fake path
x1 = nn.Variable([args.batch_size, 1, 28, 28])
#z = nn.Variable([args.batch_size, VEC_SIZE, 1, 1])
#z = vectorizer(x1,maxh = 1024)
#fake = generator(z,maxh= 1024)
z = vectorizer(x1)
fake = generator(z)
fake.persistent = True # Not to clear at backward
pred_fake = discriminator(fake)
loss_gen = F.mean(
F.sigmoid_cross_entropy(pred_fake, F.constant(1, pred_fake.shape)))
loss_vec = F.mean(F.squared_error(fake, x1))
fake_dis = fake.unlinked()
pred_fake_dis = discriminator(fake_dis)
loss_dis = F.mean(
F.sigmoid_cross_entropy(pred_fake_dis,
F.constant(0, pred_fake_dis.shape)))
# Real path
x = nn.Variable([args.batch_size, 1, 28, 28])
pred_real = discriminator(x)
loss_dis += F.mean(
F.sigmoid_cross_entropy(pred_real, F.constant(1, pred_real.shape)))
# Create Solver.
solver_gen = S.Adam(args.learning_rate, beta1=0.5)
solver_dis = S.Adam(args.learning_rate, beta1=0.5)
solver_vec = S.Adam(args.learning_rate, beta1=0.5)
with nn.parameter_scope("vec"):
solver_vec.set_parameters(nn.get_parameters())
with nn.parameter_scope("gen"):
solver_vec.set_parameters(nn.get_parameters())
with nn.parameter_scope("gen"):
solver_gen.set_parameters(nn.get_parameters())
with nn.parameter_scope("dis"):
solver_dis.set_parameters(nn.get_parameters())
# Create monitor.
import nnabla.monitor as M
monitor = M.Monitor(args.monitor_path)
monitor_loss_gen = M.MonitorSeries("Generator loss", monitor, interval=10)
monitor_loss_dis = M.MonitorSeries("Discriminator loss",
monitor,
interval=10)
monitor_loss_vec = M.MonitorSeries("Vectorizer loss", monitor, interval=10)
monitor_time = M.MonitorTimeElapsed("Time", monitor, interval=100)
monitor_fake = M.MonitorImageTile("Fake images",
monitor,
normalize_method=lambda x: x + 1 / 2.)
monitor_vec1 = M.MonitorImageTile("vec images1",
monitor,
normalize_method=lambda x: x + 1 / 2.)
monitor_vec2 = M.MonitorImageTile("vec images2",
monitor,
normalize_method=lambda x: x + 1 / 2.)
#data = data_iterator_mnist(args.batch_size, True)
data = iterator.simple_data_iterator(load_kanji_data(), args.batch_size,
True)
# Training loop.
for i in range(args.max_iter):
if i % args.model_save_interval == 0:
with nn.parameter_scope("gen"):
nn.save_parameters(
os.path.join(args.model_save_path,
"generator_param_%06d.h5" % i))
with nn.parameter_scope("dis"):
nn.save_parameters(
os.path.join(args.model_save_path,
"discriminator_param_%06d.h5" % i))
# Training forward
image, _ = data.next()
x1.d = image / 255. - 0.5
# Generator update.
solver_vec.zero_grad()
loss_vec.forward(clear_no_need_grad=True)
loss_vec.backward(clear_buffer=True)
solver_vec.weight_decay(args.weight_decay)
solver_vec.update()
monitor_vec1.add(i, fake)
monitor_vec2.add(i, x1)
monitor_loss_vec.add(i, loss_vec.d.copy())
x.d = image / 255. - 0.5 # [0, 255] to [-1, 1]
z.d = np.random.randn(*z.shape)
# Generator update.
solver_gen.zero_grad()
loss_gen.forward(clear_no_need_grad=True)
loss_gen.backward(clear_buffer=True)
solver_gen.weight_decay(args.weight_decay)
solver_gen.update()
monitor_fake.add(i, fake)
monitor_loss_gen.add(i, loss_gen.d.copy())
# Discriminator update.
solver_dis.zero_grad()
loss_dis.forward(clear_no_need_grad=True)
loss_dis.backward(clear_buffer=True)
solver_dis.weight_decay(args.weight_decay)
solver_dis.update()
monitor_loss_dis.add(i, loss_dis.d.copy())
monitor_time.add(i)
with nn.parameter_scope("gen"):
nn.save_parameters(
os.path.join(args.model_save_path, "generator_param_%06d.h5" % i))
with nn.parameter_scope("dis"):
nn.save_parameters(
os.path.join(args.model_save_path,
"discriminator_param_%06d.h5" % i))
def sr_loss(ctx, pred0, pred1):
with nn.context_scope(ctx):
pred_x_u0 = F.softmax(pred0)
pred_x_u1 = F.softmax(pred1)
loss_sr = F.mean(F.squared_error(pred_x_u0, pred_x_u1))
return loss_sr
def recon_loss(ctx, pred, x_l):
with nn.context_scope(ctx):
loss_recon = F.mean(F.squared_error(pred, x_l))
return loss_recon