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trainer.py
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from __future__ import print_function
from six.moves import range
import torch
import torch.nn as nn
import torch.optim as optim
from torch.autograd import Variable
import torch.backends.cudnn as cudnn
from PIL import Image
from miscc.config import cfg
from miscc.utils import mkdir_p
from miscc.utils import build_super_images, build_super_images2
from miscc.utils import weights_init, load_params, copy_G_params
from model import G_DCGAN, G_NET
from datasets import prepare_data
from model import RNN_ENCODER, CNN_ENCODER
from miscc.losses import words_loss
from miscc.losses import discriminator_loss, generator_loss, KL_loss
import os
import time
import numpy as np
import sys
# ################# Text to image task############################ #
class condGANTrainer(object):
def __init__(self, output_dir, data_loader, n_words, ixtoword):
if cfg.TRAIN.FLAG:
self.model_dir = os.path.join(output_dir, 'Model')
self.image_dir = os.path.join(output_dir, 'Image')
mkdir_p(self.model_dir)
mkdir_p(self.image_dir)
torch.cuda.set_device(cfg.GPU_ID)
cudnn.benchmark = True
self.batch_size = cfg.TRAIN.BATCH_SIZE
self.max_epoch = cfg.TRAIN.MAX_EPOCH
self.snapshot_interval = cfg.TRAIN.SNAPSHOT_INTERVAL
self.n_words = n_words
self.ixtoword = ixtoword
self.data_loader = data_loader
self.num_batches = len(self.data_loader)
def build_models(self):
# ###################encoders######################################## #
if cfg.TRAIN.NET_E == '':
print('Error: no pretrained text-image encoders')
return
image_encoder = CNN_ENCODER(cfg.TEXT.EMBEDDING_DIM)
img_encoder_path = cfg.TRAIN.NET_E.replace('text_encoder', 'image_encoder')
state_dict = \
torch.load(img_encoder_path, map_location=lambda storage, loc: storage)
image_encoder.load_state_dict(state_dict)
for p in image_encoder.parameters():
p.requires_grad = False
print('Load image encoder from:', img_encoder_path)
image_encoder.eval()
text_encoder = \
RNN_ENCODER(self.n_words, nhidden=cfg.TEXT.EMBEDDING_DIM)
state_dict = \
torch.load(cfg.TRAIN.NET_E,
map_location=lambda storage, loc: storage)
text_encoder.load_state_dict(state_dict)
for p in text_encoder.parameters():
p.requires_grad = False
print('Load text encoder from:', cfg.TRAIN.NET_E)
text_encoder.eval()
# #######################generator and discriminators############## #
netsD = []
if cfg.GAN.B_DCGAN:
if cfg.TREE.BRANCH_NUM ==1:
from model import D_NET64 as D_NET
elif cfg.TREE.BRANCH_NUM == 2:
from model import D_NET128 as D_NET
else: # cfg.TREE.BRANCH_NUM == 3:
from model import D_NET256 as D_NET
# TODO: elif cfg.TREE.BRANCH_NUM > 3:
netG = G_DCGAN()
netsD = [D_NET(b_jcu=False)]
else:
from model import D_NET64, D_NET128, D_NET256
netG = G_NET()
if cfg.TREE.BRANCH_NUM > 0:
netsD.append(D_NET64())
if cfg.TREE.BRANCH_NUM > 1:
netsD.append(D_NET128())
if cfg.TREE.BRANCH_NUM > 2:
netsD.append(D_NET256())
# TODO: if cfg.TREE.BRANCH_NUM > 3:
netG.apply(weights_init)
# print(netG)
for i in range(len(netsD)):
netsD[i].apply(weights_init)
# print(netsD[i])
print('# of netsD', len(netsD))
#
epoch = 0
if cfg.TRAIN.NET_G != '':
state_dict = \
torch.load(cfg.TRAIN.NET_G, map_location=lambda storage, loc: storage)
netG.load_state_dict(state_dict)
print('Load G from: ', cfg.TRAIN.NET_G)
istart = cfg.TRAIN.NET_G.rfind('_') + 1
iend = cfg.TRAIN.NET_G.rfind('.')
epoch = cfg.TRAIN.NET_G[istart:iend]
epoch = int(epoch) + 1
if cfg.TRAIN.B_NET_D:
Gname = cfg.TRAIN.NET_G
for i in range(len(netsD)):
s_tmp = Gname[:Gname.rfind('/')]
Dname = '%s/netD%d.pth' % (s_tmp, i)
print('Load D from: ', Dname)
state_dict = \
torch.load(Dname, map_location=lambda storage, loc: storage)
netsD[i].load_state_dict(state_dict)
# ########################################################### #
if cfg.CUDA:
text_encoder = text_encoder.cuda()
image_encoder = image_encoder.cuda()
netG.cuda()
for i in range(len(netsD)):
netsD[i].cuda()
return [text_encoder, image_encoder, netG, netsD, epoch]
def define_optimizers(self, netG, netsD):
optimizersD = []
num_Ds = len(netsD)
for i in range(num_Ds):
opt = optim.Adam(netsD[i].parameters(),
lr=cfg.TRAIN.DISCRIMINATOR_LR,
betas=(0.5, 0.999))
optimizersD.append(opt)
optimizerG = optim.Adam(netG.parameters(),
lr=cfg.TRAIN.GENERATOR_LR,
betas=(0.5, 0.999))
return optimizerG, optimizersD
def prepare_labels(self):
batch_size = self.batch_size
real_labels = Variable(torch.FloatTensor(batch_size).fill_(1))
fake_labels = Variable(torch.FloatTensor(batch_size).fill_(0))
match_labels = Variable(torch.LongTensor(range(batch_size)))
if cfg.CUDA:
real_labels = real_labels.cuda()
fake_labels = fake_labels.cuda()
match_labels = match_labels.cuda()
return real_labels, fake_labels, match_labels
def save_model(self, netG, avg_param_G, netsD, epoch):
backup_para = copy_G_params(netG)
load_params(netG, avg_param_G)
torch.save(netG.state_dict(),
'%s/netG_epoch_%d.pth' % (self.model_dir, epoch))
load_params(netG, backup_para)
#
for i in range(len(netsD)):
netD = netsD[i]
torch.save(netD.state_dict(),
'%s/netD%d.pth' % (self.model_dir, i))
print('Save G/Ds models.')
def set_requires_grad_value(self, models_list, brequires):
for i in range(len(models_list)):
for p in models_list[i].parameters():
p.requires_grad = brequires
def save_img_results(self, netG, noise, sent_emb, words_embs, mask,
image_encoder, captions, cap_lens,
gen_iterations, name='current'):
# Save images
fake_imgs, attention_maps, _, _ = netG(noise, sent_emb, words_embs, mask)
for i in range(len(attention_maps)):
if len(fake_imgs) > 1:
img = fake_imgs[i + 1].detach().cpu()
lr_img = fake_imgs[i].detach().cpu()
else:
img = fake_imgs[0].detach().cpu()
lr_img = None
attn_maps = attention_maps[i]
att_sze = attn_maps.size(2)
img_set, _ = \
build_super_images(img, captions, self.ixtoword,
attn_maps, att_sze, lr_imgs=lr_img)
if img_set is not None:
im = Image.fromarray(img_set)
fullpath = '%s/G_%s_%d_%d.png'\
% (self.image_dir, name, gen_iterations, i)
im.save(fullpath)
# for i in range(len(netsD)):
i = -1
img = fake_imgs[i].detach()
region_features, _ = image_encoder(img)
att_sze = region_features.size(2)
_, _, att_maps = words_loss(region_features.detach(),
words_embs.detach(),
None, cap_lens,
None, self.batch_size)
img_set, _ = \
build_super_images(fake_imgs[i].detach().cpu(),
captions, self.ixtoword, att_maps, att_sze)
if img_set is not None:
im = Image.fromarray(img_set)
fullpath = '%s/D_%s_%d.png'\
% (self.image_dir, name, gen_iterations)
im.save(fullpath)
def train(self):
text_encoder, image_encoder, netG, netsD, start_epoch = self.build_models()
avg_param_G = copy_G_params(netG)
optimizerG, optimizersD = self.define_optimizers(netG, netsD)
real_labels, fake_labels, match_labels = self.prepare_labels()
batch_size = self.batch_size
nz = cfg.GAN.Z_DIM
noise = Variable(torch.FloatTensor(batch_size, nz))
fixed_noise = Variable(torch.FloatTensor(batch_size, nz).normal_(0, 1))
if cfg.CUDA:
noise, fixed_noise = noise.cuda(), fixed_noise.cuda()
gen_iterations = 0
# gen_iterations = start_epoch * self.num_batches
for epoch in range(start_epoch, self.max_epoch):
start_t = time.time()
data_iter = iter(self.data_loader)
step = 0
while step < self.num_batches:
# reset requires_grad to be trainable for all Ds
# self.set_requires_grad_value(netsD, True)
######################################################
# (1) Prepare training data and Compute text embeddings
######################################################
data = data_iter.next()
imgs, captions, cap_lens, class_ids, keys = prepare_data(data)
hidden = text_encoder.init_hidden(batch_size)
# words_embs: batch_size x nef x seq_len
# sent_emb: batch_size x nef
words_embs, sent_emb = text_encoder(captions, cap_lens, hidden)
words_embs, sent_emb = words_embs.detach(), sent_emb.detach()
mask = (captions == 0)
num_words = words_embs.size(2)
if mask.size(1) > num_words:
mask = mask[:, :num_words]
#######################################################
# (2) Generate fake images
######################################################
noise.data.normal_(0, 1)
fake_imgs, _, mu, logvar = netG(noise, sent_emb, words_embs, mask)
#######################################################
# (3) Update D network
######################################################
errD_total = 0
D_logs = ''
for i in range(len(netsD)):
netsD[i].zero_grad()
errD = discriminator_loss(netsD[i], imgs[i], fake_imgs[i],
sent_emb, real_labels, fake_labels)
# backward and update parameters
errD.backward()
optimizersD[i].step()
errD_total += errD
#D_logs += 'errD%d: %.2f ' % (i, errD.data[0])
D_logs += 'errD%d: %.2f ' % (i, errD.item())
#######################################################
# (4) Update G network: maximize log(D(G(z)))
######################################################
# compute total loss for training G
step += 1
gen_iterations += 1
# do not need to compute gradient for Ds
# self.set_requires_grad_value(netsD, False)
netG.zero_grad()
errG_total, G_logs = \
generator_loss(netsD, image_encoder, fake_imgs, real_labels,
words_embs, sent_emb, match_labels, cap_lens, class_ids)
kl_loss = KL_loss(mu, logvar)
errG_total += kl_loss
#G_logs += 'kl_loss: %.2f ' % kl_loss.data[0]
G_logs += 'kl_loss: %.2f ' % kl_loss.item()
# backward and update parameters
errG_total.backward()
optimizerG.step()
for p, avg_p in zip(netG.parameters(), avg_param_G):
avg_p.mul_(0.999).add_(0.001, p.data)
if gen_iterations % 100 == 0:
print(D_logs + '\n' + G_logs)
# save images
if gen_iterations % 1000 == 0:
backup_para = copy_G_params(netG)
load_params(netG, avg_param_G)
self.save_img_results(netG, fixed_noise, sent_emb,
words_embs, mask, image_encoder,
captions, cap_lens, epoch, name='average')
load_params(netG, backup_para)
#
# self.save_img_results(netG, fixed_noise, sent_emb,
# words_embs, mask, image_encoder,
# captions, cap_lens,
# epoch, name='current')
end_t = time.time()
#print('''[%d/%d][%d]
# Loss_D: %.2f Loss_G: %.2f Time: %.2fs'''
# % (epoch, self.max_epoch, self.num_batches,
# errD_total.data[0], errG_total.data[0],
# end_t - start_t))
print('''[%d/%d][%d]
Loss_D: %.2f Loss_G: %.2f Time: %.2fs'''
% (epoch, self.max_epoch, self.num_batches,
errD_total.item(), errG_total.item(),
end_t - start_t))
if epoch % cfg.TRAIN.SNAPSHOT_INTERVAL == 0: # and epoch != 0:
self.save_model(netG, avg_param_G, netsD, epoch)
self.save_model(netG, avg_param_G, netsD, self.max_epoch)
def eval(self):
text_encoder, image_encoder, netG, netsD, start_epoch = self.build_models()
avg_param_G = copy_G_params(netG)
optimizerG, optimizersD = self.define_optimizers(netG, netsD)
real_labels, fake_labels, match_labels = self.prepare_labels()
batch_size = self.batch_size
nz = cfg.GAN.Z_DIM
noise = Variable(torch.FloatTensor(batch_size, nz))
fixed_noise = Variable(torch.FloatTensor(batch_size, nz).normal_(0, 1))
if cfg.CUDA:
noise, fixed_noise = noise.cuda(), fixed_noise.cuda()
gen_iterations = 0
start_t = time.time()
data_iter = iter(self.data_loader)
step = 0
while step < self.num_batches:
# reset requires_grad to be trainable for all Ds
# self.set_requires_grad_value(netsD, True)
######################################################
# (1) Prepare training data and Compute text embeddings
######################################################
data = data_iter.next()
imgs, captions, cap_lens, class_ids, keys = prepare_data(data)
hidden = text_encoder.init_hidden(batch_size)
# words_embs: batch_size x nef x seq_len
# sent_emb: batch_size x nef
words_embs, sent_emb = text_encoder(captions, cap_lens, hidden)
words_embs, sent_emb = words_embs.detach(), sent_emb.detach()
mask = (captions == 0)
num_words = words_embs.size(2)
if mask.size(1) > num_words:
mask = mask[:, :num_words]
#######################################################
# (2) Generate fake images
######################################################
noise.data.normal_(0, 1)
fake_imgs, _, mu, logvar = netG(noise, sent_emb, words_embs, mask)
#######################################################
# (3) Update D network
######################################################
errD_total = 0
D_logs = ''
for i in range(len(netsD)):
netsD[i].zero_grad()
errD = discriminator_loss(netsD[i], imgs[i], fake_imgs[i],
sent_emb, real_labels, fake_labels)
errD_total += errD
D_logs += 'errD%d: %.2f ' % (i, errD.item())
#######################################################
# (4) Update G network: maximize log(D(G(z)))
######################################################
# compute total loss for training G
step += 1
gen_iterations += 1
netG.zero_grad()
errG_total, G_logs = \
generator_loss(netsD, image_encoder, fake_imgs, real_labels,
words_embs, sent_emb, match_labels, cap_lens, class_ids)
kl_loss = KL_loss(mu, logvar)
errG_total += kl_loss
G_logs += 'kl_loss: %.2f ' % kl_loss.item()
print(D_logs + '\n' + G_logs)
end_t = time.time()
print('''[%d/%d][%d]
Loss_D: %.2f Loss_G: %.2f Time: %.2fs'''
% (epoch, self.max_epoch, self.num_batches,
errD_total.item(), errG_total.item(),
end_t - start_t))
def save_singleimages(self, images, filenames, save_dir,
split_dir, sentenceID=0):
for i in range(images.size(0)):
s_tmp = '%s/single_samples/%s/%s' %\
(save_dir, split_dir, filenames[i])
folder = s_tmp[:s_tmp.rfind('/')]
if not os.path.isdir(folder):
print('Make a new folder: ', folder)
mkdir_p(folder)
fullpath = '%s_%d.jpg' % (s_tmp, sentenceID)
# range from [-1, 1] to [0, 1]
# img = (images[i] + 1.0) / 2
img = images[i].add(1).div(2).mul(255).clamp(0, 255).byte()
# range from [0, 1] to [0, 255]
ndarr = img.permute(1, 2, 0).data.cpu().numpy()
im = Image.fromarray(ndarr)
im.save(fullpath)
def sampling(self, split_dir):
if cfg.TRAIN.NET_G == '':
print('Error: the path for morels is not found!')
else:
if split_dir == 'test':
#split_dir = 'valid'
split_dir = 'validation' #changed by liang
# Build and load the generator
if cfg.GAN.B_DCGAN:
netG = G_DCGAN()
else:
netG = G_NET()
netG.apply(weights_init)
netG.cuda()
netG.eval()
#
text_encoder = RNN_ENCODER(self.n_words, nhidden=cfg.TEXT.EMBEDDING_DIM)
state_dict = \
torch.load(cfg.TRAIN.NET_E, map_location=lambda storage, loc: storage)
text_encoder.load_state_dict(state_dict)
print('Load text encoder from:', cfg.TRAIN.NET_E)
text_encoder = text_encoder.cuda()
text_encoder.eval()
batch_size = self.batch_size
nz = cfg.GAN.Z_DIM
noise = Variable(torch.FloatTensor(batch_size, nz), volatile=True)
noise = noise.cuda()
model_dir = cfg.TRAIN.NET_G
state_dict = \
torch.load(model_dir, map_location=lambda storage, loc: storage)
# state_dict = torch.load(cfg.TRAIN.NET_G)
netG.load_state_dict(state_dict)
print('Load G from: ', model_dir)
# the path to save generated images
s_tmp = model_dir[:model_dir.rfind('.pth')]
save_dir = '%s/%s' % (s_tmp, split_dir)
mkdir_p(save_dir)
cnt = 0
for _ in range(1): # (cfg.TEXT.CAPTIONS_PER_IMAGE):
for step, data in enumerate(self.data_loader, 0):
cnt += batch_size
if step % 100 == 0:
print('step: ', step)
# if step > 50:
# break
imgs, captions, cap_lens, class_ids, keys = prepare_data(data)
hidden = text_encoder.init_hidden(batch_size)
# words_embs: batch_size x nef x seq_len
# sent_emb: batch_size x nef
words_embs, sent_emb = text_encoder(captions, cap_lens, hidden)
words_embs, sent_emb = words_embs.detach(), sent_emb.detach()
mask = (captions == 0)
num_words = words_embs.size(2)
if mask.size(1) > num_words:
mask = mask[:, :num_words]
#######################################################
# (2) Generate fake images
######################################################
noise.data.normal_(0, 1)
fake_imgs, _, _, _ = netG(noise, sent_emb, words_embs, mask)
for j in range(batch_size):
s_tmp = '%s/single/%s' % (save_dir, keys[j])
folder = s_tmp[:s_tmp.rfind('/')]
if not os.path.isdir(folder):
print('Make a new folder: ', folder)
mkdir_p(folder)
k = -1
# for k in range(len(fake_imgs)):
im = fake_imgs[k][j].data.cpu().numpy()
# [-1, 1] --> [0, 255]
im = (im + 1.0) * 127.5
im = im.astype(np.uint8)
im = np.transpose(im, (1, 2, 0))
im = Image.fromarray(im)
fullpath = '%s_s%d.png' % (s_tmp, k)
im.save(fullpath)
def gen_example(self, data_dic):
if cfg.TRAIN.NET_G == '':
print('Error: the path for models is not found!')
else:
# Build and load the generator
text_encoder = \
RNN_ENCODER(self.n_words, nhidden=cfg.TEXT.EMBEDDING_DIM)
state_dict = \
torch.load(cfg.TRAIN.NET_E, map_location=lambda storage, loc: storage)
text_encoder.load_state_dict(state_dict)
print('Load text encoder from:', cfg.TRAIN.NET_E)
text_encoder = text_encoder.cuda()
text_encoder.eval()
# the path to save generated images
if cfg.GAN.B_DCGAN:
netG = G_DCGAN()
else:
netG = G_NET()
s_tmp = cfg.TRAIN.NET_G[:cfg.TRAIN.NET_G.rfind('.pth')]
model_dir = cfg.TRAIN.NET_G
state_dict = \
torch.load(model_dir, map_location=lambda storage, loc: storage)
netG.load_state_dict(state_dict)
print('Load G from: ', model_dir)
netG.cuda()
netG.eval()
for key in data_dic:
save_dir = '%s/%s' % (s_tmp, key)
mkdir_p(save_dir)
captions, cap_lens, sorted_indices = data_dic[key]
batch_size = captions.shape[0]
nz = cfg.GAN.Z_DIM
captions = Variable(torch.from_numpy(captions), volatile=True)
cap_lens = Variable(torch.from_numpy(cap_lens), volatile=True)
captions = captions.cuda()
cap_lens = cap_lens.cuda()
for i in range(1): # 16
noise = Variable(torch.FloatTensor(batch_size, nz), volatile=True)
noise = noise.cuda()
#######################################################
# (1) Extract text embeddings
######################################################
hidden = text_encoder.init_hidden(batch_size)
# words_embs: batch_size x nef x seq_len
# sent_emb: batch_size x nef
words_embs, sent_emb = text_encoder(captions, cap_lens, hidden)
mask = (captions == 0)
#######################################################
# (2) Generate fake images
######################################################
noise.data.normal_(0, 1)
fake_imgs, attention_maps, _, _ = netG(noise, sent_emb, words_embs, mask)
# G attention
cap_lens_np = cap_lens.cpu().data.numpy()
for j in range(batch_size):
save_name = '%s/%d_s_%d' % (save_dir, i, sorted_indices[j])
for k in range(len(fake_imgs)):
im = fake_imgs[k][j].data.cpu().numpy()
im = (im + 1.0) * 127.5
im = im.astype(np.uint8)
# print('im', im.shape)
im = np.transpose(im, (1, 2, 0))
# print('im', im.shape)
im = Image.fromarray(im)
fullpath = '%s_g%d.png' % (save_name, k)
im.save(fullpath)
for k in range(len(attention_maps)):
if len(fake_imgs) > 1:
im = fake_imgs[k + 1].detach().cpu()
else:
im = fake_imgs[0].detach().cpu()
attn_maps = attention_maps[k]
att_sze = attn_maps.size(2)
img_set, sentences = \
build_super_images2(im[j].unsqueeze(0),
captions[j].unsqueeze(0),
[cap_lens_np[j]], self.ixtoword,
[attn_maps[j]], att_sze)
if img_set is not None:
im = Image.fromarray(img_set)
fullpath = '%s_a%d.png' % (save_name, k)
im.save(fullpath)