Files
2017-03-13 14:35:34 +09:00

72 lines
2.2 KiB
Python

from data import get_loader
from vocab import Vocabulary
from model import EncoderCNN, DecoderRNN
from torch.autograd import Variable
from torch.nn.utils.rnn import pack_padded_sequence
import torch
import torch.nn as nn
import numpy as np
import torchvision.transforms as T
import pickle
# Hyper Parameters
num_epochs = 1
batch_size = 32
embed_size = 256
hidden_size = 512
crop_size = 224
num_layers = 1
learning_rate = 0.001
train_image_path = './data/train2014resized/'
train_json_path = './data/annotations/captions_train2014.json'
# Image Preprocessing
transform = T.Compose([
T.RandomCrop(crop_size),
T.RandomHorizontalFlip(),
T.ToTensor(),
T.Normalize(mean=(0.5, 0.5, 0.5), std=(0.5, 0.5, 0.5))])
# Load Vocabulary Wrapper
with open('./data/vocab.pkl', 'rb') as f:
vocab = pickle.load(f)
# Build Dataset Loader
train_loader = get_loader(train_image_path, train_json_path, vocab, transform,
batch_size=batch_size, shuffle=True, num_workers=2)
total_step = len(train_loader)
# Build Models
encoder = EncoderCNN(embed_size)
decoder = DecoderRNN(embed_size, hidden_size, len(vocab), num_layers)
encoder.cuda()
decoder.cuda()
# Loss and Optimizer
criterion = nn.CrossEntropyLoss()
params = list(decoder.parameters()) + list(encoder.resnet.fc.parameters())
optimizer = torch.optim.Adam(params, lr=learning_rate)
# Train the Decoder
for epoch in range(num_epochs):
for i, (images, captions, lengths) in enumerate(train_loader):
# Set mini-batch dataset
images = Variable(images).cuda()
captions = Variable(captions).cuda()
targets = pack_padded_sequence(captions, lengths, batch_first=True)[0]
# Forward, Backward and Optimize
decoder.zero_grad()
features = encoder(images)
outputs = decoder(features, captions, lengths)
loss = criterion(outputs, targets)
loss.backward()
optimizer.step()
if i % 100 == 0:
print('Epoch [%d/%d], Step [%d/%d], Loss: %.4f, Perplexity: %5.4f'
%(epoch, num_epochs, i, total_step, loss.data[0], np.exp(loss.data[0])))
# Save the Model
torch.save(decoder, 'decoder.pkl')
torch.save(encoder, 'encoder.pkl')