| import argparse |
| import logging |
| import os |
| import random |
| import sys |
| import time |
| import numpy as np |
| import torch |
| import torch.nn as nn |
| import torch.optim as optim |
| from tensorboardX import SummaryWriter |
| from torch.nn.modules.loss import CrossEntropyLoss |
| from torch.utils.data import DataLoader |
| from tqdm import tqdm |
| from utils import DiceLoss |
| from torchvision import transforms |
| from utils import test_single_volume |
|
|
| def trainer_synapse(args, model, snapshot_path): |
| from datasets.dataset_synapse import Synapse_dataset, RandomGenerator |
| logging.basicConfig(filename=snapshot_path + "/log.txt", level=logging.INFO, |
| format='[%(asctime)s.%(msecs)03d] %(message)s', datefmt='%H:%M:%S') |
| logging.getLogger().addHandler(logging.StreamHandler(sys.stdout)) |
| logging.info(str(args)) |
| base_lr = args.base_lr |
| num_classes = args.num_classes |
| batch_size = args.batch_size * args.n_gpu |
| |
| db_train = Synapse_dataset(base_dir=args.root_path, list_dir=args.list_dir, split="train", |
| transform=transforms.Compose( |
| [RandomGenerator(output_size=[args.img_size, args.img_size])])) |
| print("The length of train set is: {}".format(len(db_train))) |
|
|
| def worker_init_fn(worker_id): |
| random.seed(args.seed + worker_id) |
|
|
| trainloader = DataLoader(db_train, batch_size=batch_size, shuffle=True, num_workers=8, pin_memory=True, |
| worker_init_fn=worker_init_fn) |
| if args.n_gpu > 1: |
| model = nn.DataParallel(model) |
| model.train() |
| ce_loss = CrossEntropyLoss() |
| dice_loss = DiceLoss(num_classes) |
| optimizer = optim.SGD(model.parameters(), lr=base_lr, momentum=0.9, weight_decay=0.0001) |
| writer = SummaryWriter(snapshot_path + '/log') |
| iter_num = 0 |
| max_epoch = args.max_epochs |
| max_iterations = args.max_epochs * len(trainloader) |
| logging.info("{} iterations per epoch. {} max iterations ".format(len(trainloader), max_iterations)) |
| best_performance = 0.0 |
| iterator = tqdm(range(max_epoch), ncols=70) |
| for epoch_num in iterator: |
| for i_batch, sampled_batch in enumerate(trainloader): |
| image_batch, label_batch = sampled_batch['image'], sampled_batch['label'] |
| image_batch, label_batch = image_batch.cuda(), label_batch.cuda() |
| outputs = model(image_batch) |
| loss_ce = ce_loss(outputs, label_batch[:].long()) |
| loss_dice = dice_loss(outputs, label_batch, softmax=True) |
| loss = 0.4 * loss_ce + 0.6 * loss_dice |
| optimizer.zero_grad() |
| loss.backward() |
| optimizer.step() |
| lr_ = base_lr * (1.0 - iter_num / max_iterations) ** 0.9 |
| for param_group in optimizer.param_groups: |
| param_group['lr'] = lr_ |
|
|
| iter_num = iter_num + 1 |
| writer.add_scalar('info/lr', lr_, iter_num) |
| writer.add_scalar('info/total_loss', loss, iter_num) |
| writer.add_scalar('info/loss_ce', loss_ce, iter_num) |
|
|
| logging.info('iteration %d : loss : %f, loss_ce: %f' % (iter_num, loss.item(), loss_ce.item())) |
|
|
| if iter_num % 20 == 0: |
| image = image_batch[1, 0:1, :, :] |
| image = (image - image.min()) / (image.max() - image.min()) |
| writer.add_image('train/Image', image, iter_num) |
| outputs = torch.argmax(torch.softmax(outputs, dim=1), dim=1, keepdim=True) |
| writer.add_image('train/Prediction', outputs[1, ...] * 50, iter_num) |
| labs = label_batch[1, ...].unsqueeze(0) * 50 |
| writer.add_image('train/GroundTruth', labs, iter_num) |
|
|
| save_interval = 50 |
| if epoch_num > int(max_epoch / 2) and (epoch_num + 1) % save_interval == 0: |
| save_mode_path = os.path.join(snapshot_path, 'epoch_' + str(epoch_num) + '.pth') |
| torch.save(model.state_dict(), save_mode_path) |
| logging.info("save model to {}".format(save_mode_path)) |
|
|
| if epoch_num >= max_epoch - 1: |
| save_mode_path = os.path.join(snapshot_path, 'epoch_' + str(epoch_num) + '.pth') |
| torch.save(model.state_dict(), save_mode_path) |
| logging.info("save model to {}".format(save_mode_path)) |
| iterator.close() |
| break |
|
|
| writer.close() |
| return "Training Finished!" |