def eval_h5(conf, ckpt):
"""
Train model for a number of steps.
Args:
conf: configuration dictionary
ckpt: restore from ckpt
"""
cropw = conf['cropw']
mb_size = conf['mb_size']
path_tmp = conf['path_tmp']
n_epochs = conf['n_epochs']
cw = conf['cw']
grad_norm_thresh = conf['grad_norm_thresh']
# Prepare data
tr_stream, te_stream = tools.prepare_data(conf)
n_tr = tr_stream.dataset.num_examples
n_te = te_stream.dataset.num_examples
with tf.Graph().as_default(), tf.device('/cpu:0' if FLAGS.dev_assign else None):
# Placeholders
Xs = [tf.placeholder(tf.float32, [None, cw, cw, 1], name='X_%02d' % i) \
for i in range(FLAGS.num_gpus)]
Ys = [tf.placeholder(tf.float32, [None, cw - 2*cropw, cw - 2*cropw, 1],
name='Y_%02d' % i) \
for i in range(FLAGS.num_gpus)]
# Calculate the gradients for each model tower
tower_grads = []
y_splits = []
for i in range(FLAGS.num_gpus):
with tf.device(('/gpu:%d' % i) if FLAGS.dev_assign else None):
with tf.name_scope('%s_%02d' % (FLAGS.tower_name, i)) as scope:
# Calculate the loss for one tower. This function constructs
# the entire model but shares the variables across all towers.
y_split = model.inference(Xs[i], conf)
y_splits.append(y_split)
total_loss = model.loss(y_split, Ys[i], conf, scope)
# Reuse variables for the next tower.
tf.get_variable_scope().reuse_variables()
y = tf.concat(0, y_splits, name='y')
# Tensorflow boilerplate
sess, saver, summ_writer, summ_op = tools.tf_boilerplate(None, conf, ckpt)
# Evaluation
psnr_tr = eval_epoch(Xs, Ys, y, sess, tr_stream, cropw)
psnr_te = eval_epoch(Xs, Ys, y, sess, te_stream, cropw)
print('approx psnr_tr=%.3f' % psnr_tr)
print('approx psnr_te=%.3f' % psnr_te)
tr_stream.close()
te_stream.close()
def train(conf, ckpt=None):
"""
Train model for a number of steps.
Args:
conf: configuration dictionary
ckpt: restore from ckpt
"""
cropw = conf['cropw']
mb_size = conf['mb_size']
path_tmp = conf['path_tmp']
n_epochs = conf['n_epochs']
cw = conf['cw']
grad_norm_thresh = conf['grad_norm_thresh']
tools.reset_tmp(path_tmp)
# Prepare data
tr_stream, te_stream = tools.prepare_data(conf)
n_tr = tr_stream.dataset.num_examples
n_te = te_stream.dataset.num_examples
with tf.Graph().as_default(), tf.device('/cpu:0' if FLAGS.dev_assign else None):
# Exponential decay learning rate
global_step = tf.get_variable('global_step', [],
initializer=tf.constant_initializer(0), dtype=tf.int32,
trainable=False)
lr = tools.exp_decay_lr(global_step, n_tr, conf)
# Create an optimizer that performs gradient descent
opt = tf.train.AdamOptimizer(lr)
# Placeholders
Xs = [tf.placeholder(tf.float32, [None, cw, cw, 1], name='X_%02d' % i) \
for i in range(FLAGS.num_gpus)]
Ys = [tf.placeholder(tf.float32, [None, cw - 2*cropw, cw - 2*cropw, 1],
name='Y_%02d' % i) \
for i in range(FLAGS.num_gpus)]
# Calculate the gradients for each model tower
tower_grads = []
y_splits = []
for i in range(FLAGS.num_gpus):
with tf.device(('/gpu:%d' % i) if FLAGS.dev_assign else None):
with tf.name_scope('%s_%02d' % (FLAGS.tower_name, i)) as scope:
# Calculate the loss for one tower. This function constructs
# the entire model but shares the variables across all towers.
y_split = model.inference(Xs[i], conf)
y_splits.append(y_split)
total_loss = model.loss(y_split, Ys[i], conf, scope)
# Calculate the gradients for the batch of data on this tower.
gvs = opt.compute_gradients(total_loss)
# Optionally clip gradients.
if grad_norm_thresh > 0:
gvs = tools.clip_by_norm(gvs, grad_norm_thresh)
# Keep track of the gradients across all towers.
tower_grads.append(gvs)
# Reuse variables for the next tower.
tf.get_variable_scope().reuse_variables()
# Retain the summaries from the final tower.
summs = tf.get_collection(tf.GraphKeys.SUMMARIES, scope)
y = tf.concat(0, y_splits, name='y')
# We must calculate the mean of each gradient. Note that this is the
# synchronization point across all towers.
gvs = tools.average_gradients(tower_grads)
# Apply the gradients to adjust the shared variables.
apply_grad_op = opt.apply_gradients(gvs, global_step=global_step)
# Add a summary to track the learning rate.
summs.append(tf.scalar_summary('learning_rate', lr))
# Add histograms for gradients.
for g, v in gvs:
if g:
v_name = re.sub('%s_[0-9]*/' % FLAGS.tower_name, '', v.op.name)
summs.append(tf.histogram_summary(v_name + '/gradients', g))
# Tensorflow boilerplate
sess, saver, summ_writer, summ_op = tools.tf_boilerplate(summs, conf, ckpt)
# Baseline error
bpsnr_tr = tools.baseline_psnr(tr_stream)
bpsnr_te = tools.baseline_psnr(te_stream)
print('approx baseline psnr_tr=%.3f' % bpsnr_tr)
print('approx baseline psnr_te=%.3f' % bpsnr_te)
# Train
format_str = ('%s| %04d PSNR=%.3f (Tr: %.1fex/s; %.1fs/batch)'
'(Te: %.1fex/s; %.1fs/batch)')
step = 0
for epoch in range(n_epochs):
print('--- Epoch %d ---' % epoch)
# Training
for X_c, y_c in tr_stream.get_epoch_iterator():
y_c = y_c[:, cropw:-cropw, cropw:-cropw]
chunk_size = X_c.shape[0]
gpu_chunk = chunk_size // FLAGS.num_gpus
dict_input1 = [(Xs[i], X_c[i*gpu_chunk : \
((i + 1)*gpu_chunk) \
if (i != FLAGS.num_gpus - 1) \
else chunk_size]) \
for i in range(FLAGS.num_gpus)]
dict_input2 = [(Ys[i], y_c[i*gpu_chunk : \
((i + 1)*gpu_chunk) \
if (i != FLAGS.num_gpus - 1) \
else chunk_size]) \
for i in range(FLAGS.num_gpus)]
feed = dict(dict_input1 + dict_input2)
start_time = time.time()
sess.run(apply_grad_op, feed_dict=feed)
duration_tr = time.time() - start_time
if step % 10 == 0:
feed2 = dict(dict_input1)
start_time = time.time()
y_eval = sess.run(y, feed_dict=feed2)
duration_eval = time.time() - start_time
psnr = tools.eval_psnr(y_c, y_eval)
ex_per_step_tr = mb_size * FLAGS.num_gpus / duration_tr
ex_per_step_eval = mb_size * FLAGS.num_gpus / duration_eval
print(format_str % (datetime.now().time(), step, psnr,
ex_per_step_tr, float(duration_tr / FLAGS.num_gpus),
ex_per_step_eval, float(duration_eval / FLAGS.num_gpus)))
if step % 25 == 0:
summ_str = sess.run(summ_op, feed_dict=feed)
summ_writer.add_summary(summ_str, step)
if step % 100 == 0:
saver.save(sess, os.path.join(path_tmp, 'ckpt'),
global_step=step)
step += 1
# Evaluation
#psnr_tr = eval_epoch(Xs, Ys, y, sess, tr_stream, cropw)
#psnr_te = eval_epoch(Xs, Ys, y, sess, te_stream, cropw)
#print('approx psnr_tr=%.3f' % psnr_tr)
#print('approx psnr_te=%.3f' % psnr_te)
saver.save(sess, os.path.join(path_tmp, 'ckpt'),
global_step=step)
saver.save(sess, os.path.join(path_tmp, 'ckpt'),
global_step=step)
tr_stream.close()
te_stream.close()