import argparse import json import time import test from models import * from utils.datasets import JointDataset, collate_fn from utils.utils import * from utils.log import logger from torchvision.transforms import transforms as T def train( cfg, data_cfg, resume=False, epochs=100, batch_size=16, accumulated_batches=1, freeze_backbone=False, opt=None, ): weights = 'weights' mkdir_if_missing(weights) latest = osp.join(weights, 'latest.pt') torch.backends.cudnn.benchmark = True # unsuitable for multiscale # Configure run f = open(data_cfg) data_config = json.load(f) trainset_paths = data_config['train'] dataset_root = data_config['root'] f.close() cfg_dict = parse_model_cfg(cfg) img_size = [int(cfg_dict[0]['width']), int(cfg_dict[0]['height'])] # Get dataloader transforms = T.Compose([T.ToTensor()]) dataset = JointDataset(dataset_root, trainset_paths, img_size, augment=True, transforms=transforms) dataloader = torch.utils.data.DataLoader(dataset, batch_size=batch_size, shuffle=True, num_workers=8, pin_memory=True, drop_last=True, collate_fn=collate_fn) # Initialize model model = Darknet(cfg_dict, dataset.nID) cutoff = -1 # backbone reaches to cutoff layer start_epoch = 0 if resume: checkpoint = torch.load(latest, map_location='cpu') # Load weights to resume from model.load_state_dict(checkpoint['model']) model.cuda().train() # Set optimizer optimizer = torch.optim.SGD(filter(lambda x: x.requires_grad, model.parameters()), lr=opt.lr, momentum=.9) start_epoch = checkpoint['epoch'] + 1 if checkpoint['optimizer'] is not None: optimizer.load_state_dict(checkpoint['optimizer']) del checkpoint # current, saved else: # Initialize model with backbone (optional) if cfg.endswith('yolov3.cfg'): load_darknet_weights(model, osp.join(weights ,'darknet53.conv.74')) cutoff = 75 elif cfg.endswith('yolov3-tiny.cfg'): load_darknet_weights(model, osp.join(weights , 'yolov3-tiny.conv.15')) cutoff = 15 model.cuda().train() # Set optimizer optimizer = torch.optim.SGD(filter(lambda x: x.requires_grad, model.parameters()), lr=opt.lr, momentum=.9, weight_decay=1e-4) model = torch.nn.DataParallel(model) # Set scheduler scheduler = torch.optim.lr_scheduler.MultiStepLR(optimizer, milestones=[int(0.5*opt.epochs), int(0.75*opt.epochs)], gamma=0.1) # An important trick for detection: freeze bn during fine-tuning if not opt.unfreeze_bn: for i, (name, p) in enumerate(model.named_parameters()): p.requires_grad = False if 'batch_norm' in name else True model_info(model) t0 = time.time() for epoch in range(epochs): epoch += start_epoch logger.info(('%8s%12s' + '%10s' * 6) % ( 'Epoch', 'Batch', 'box', 'conf', 'id', 'total', 'nTargets', 'time')) # Freeze darknet53.conv.74 for first epoch if freeze_backbone and (epoch < 2): for i, (name, p) in enumerate(model.named_parameters()): if int(name.split('.')[2]) < cutoff: # if layer < 75 p.requires_grad = False if (epoch == 0) else True ui = -1 rloss = defaultdict(float) # running loss optimizer.zero_grad() for i, (imgs, targets, _, _, targets_len) in enumerate(dataloader): if sum([len(x) for x in targets]) < 1: # if no targets continue continue # SGD burn-in burnin = min(1000, len(dataloader)) if (epoch == 0) & (i <= burnin): lr = opt.lr * (i / burnin) **4 for g in optimizer.param_groups: g['lr'] = lr # Compute loss, compute gradient, update parameters loss, components = model(imgs.cuda(), targets.cuda(), targets_len.cuda()) components = torch.mean(components.view(-1, 5),dim=0) loss = torch.mean(loss) loss.backward() # accumulate gradient for x batches before optimizing if ((i + 1) % accumulated_batches == 0) or (i == len(dataloader) - 1): optimizer.step() optimizer.zero_grad() # Running epoch-means of tracked metrics ui += 1 for ii, key in enumerate(model.module.loss_names): rloss[key] = (rloss[key] * ui + components[ii]) / (ui + 1) s = ('%8s%12s' + '%10.3g' * 6) % ( '%g/%g' % (epoch, epochs - 1), '%g/%g' % (i, len(dataloader) - 1), rloss['box'], rloss['conf'], rloss['id'],rloss['loss'], rloss['nT'], time.time() - t0) t0 = time.time() if i % opt.print_interval == 0: logger.info(s) # Save latest checkpoint checkpoint = {'epoch': epoch, 'model': model.module.state_dict(), 'optimizer': optimizer.state_dict()} torch.save(checkpoint, latest) # Calculate mAP if epoch % opt.test_interval ==0: with torch.no_grad(): mAP, R, P = test.test(cfg, data_cfg, weights=latest, batch_size=batch_size, print_interval=40) test.test_emb(cfg, data_cfg, weights=latest, batch_size=batch_size, print_interval=40) # Call scheduler.step() after opimizer.step() with pytorch > 1.1.0 scheduler.step() if __name__ == '__main__': parser = argparse.ArgumentParser() parser.add_argument('--epochs', type=int, default=30, help='number of epochs') parser.add_argument('--batch-size', type=int, default=32, help='size of each image batch') parser.add_argument('--accumulated-batches', type=int, default=1, help='number of batches before optimizer step') parser.add_argument('--cfg', type=str, default='cfg/yolov3_1088x608.cfg', help='cfg file path') parser.add_argument('--data-cfg', type=str, default='cfg/ccmcpe.json', help='coco.data file path') parser.add_argument('--resume', action='store_true', help='resume training flag') parser.add_argument('--print-interval', type=int, default=40, help='print interval') parser.add_argument('--test-interval', type=int, default=9, help='test interval') parser.add_argument('--lr', type=float, default=1e-2, help='init lr') parser.add_argument('--unfreeze-bn', action='store_true', help='unfreeze bn') opt = parser.parse_args() init_seeds() train( opt.cfg, opt.data_cfg, resume=opt.resume, epochs=opt.epochs, batch_size=opt.batch_size, accumulated_batches=opt.accumulated_batches, opt=opt, )