解释net.load_state_dict(torch.load(args.weight_path, map_location='cpu'), strict=False)

这行代码的作用是加载一个预训练模型的权重参数。torch.load()函数用于加载预训练模型的权重参数，参数args.weight_path指定了预训练模型的权重文件路径。map_location参数指定了权重参数的位置，这里设置为'cpu'表示将权重参数加载到CPU上，如果不指定该参数，则默认加载到GPU上。strict参数表示是否严格匹配预训练模型和当前模型的结构，如果strict=True，则预训练模型和当前模型的结构必须完全一致，否则会报错；如果strict=False，则预训练模型和当前模型的结构可以不完全一致，只要保证加载的权重参数名称相同即可。最终，net.load_state_dict()函数将预训练模型的权重参数加载到当前模型中。

相关问题

if args.weights != "": assert os.path.exists(args.weights), "weights file: '{}' not exist.".format(args.weights) weights_dict = torch.load(args.weights, map_location=device)["model"] # 删除有关分类类别的权重 for k in list(weights_dict.keys()): if "head" in k: del weights_dict[k] print(model.load_state_dict(weights_dict, strict=False))

这段代码的作用是加载预训练模型的权重，并将其应用于当前的模型中。如果 `args.weights` 参数不为空，则会检查指定的权重文件是否存在。接着，使用 `torch.load()` 函数加载权重文件，`map_location=device` 参数表示将模型加载到指定的设备上（例如 CPU 或 GPU）。然后，删除与分类类别相关的权重（因为当前的模型可能与预训练模型的分类类别不同）。最后，使用 `model.load_state_dict()` 函数将加载的权重应用于当前的模型中，`strict=False` 参数表示允许加载的权重字典中存在当前模型中不存在的键。函数返回值为 `None`。

import torch, os, cv2 from model.model import parsingNet from utils.common import merge_config from utils.dist_utils import dist_print import torch import scipy.special, tqdm import numpy as np import torchvision.transforms as transforms from data.dataset import LaneTestDataset from data.constant import culane_row_anchor, tusimple_row_anchor if __name__ == "__main__": torch.backends.cudnn.benchmark = True args, cfg = merge_config() dist_print('start testing...') assert cfg.backbone in ['18','34','50','101','152','50next','101next','50wide','101wide'] if cfg.dataset == 'CULane': cls_num_per_lane = 18 elif cfg.dataset == 'Tusimple': cls_num_per_lane = 56 else: raise NotImplementedError net = parsingNet(pretrained = False, backbone=cfg.backbone,cls_dim = (cfg.griding_num+1,cls_num_per_lane,4), use_aux=False).cuda() # we dont need auxiliary segmentation in testing state_dict = torch.load(cfg.test_model, map_location='cpu')['model'] compatible_state_dict = {} for k, v in state_dict.items(): if 'module.' in k: compatible_state_dict[k[7:]] = v else: compatible_state_dict[k] = v net.load_state_dict(compatible_state_dict, strict=False) net.eval() img_transforms = transforms.Compose([ transforms.Resize((288, 800)), transforms.ToTensor(), transforms.Normalize((0.485, 0.456, 0.406), (0.229, 0.224, 0.225)), ]) if cfg.dataset == 'CULane': splits = ['test0_normal.txt', 'test1_crowd.txt', 'test2_hlight.txt', 'test3_shadow.txt', 'test4_noline.txt', 'test5_arrow.txt', 'test6_curve.txt', 'test7_cross.txt', 'test8_night.txt'] datasets = [LaneTestDataset(cfg.data_root,os.path.join(cfg.data_root, 'list/test_split/'+split),img_transform = img_transforms) for split in splits] img_w, img_h = 1640, 590 row_anchor = culane_row_anchor elif cfg.dataset == 'Tusimple': splits = ['test.txt'] datasets = [LaneTestDataset(cfg.data_root,os.path.join(cfg.data_root, split),img_transform = img_transforms) for split in splits] img_w, img_h = 1280, 720 row_anchor = tusimple_row_anchor else: raise NotImplementedError for split, dataset in zip(splits, datasets): loader = torch.utils.data.DataLoader(dataset, batch_size=1, shuffle = False, num_workers=1) fourcc = cv2.VideoWriter_fourcc(*'MJPG') print(split[:-3]+'avi') vout = cv2.VideoWriter(split[:-3]+'avi', fourcc , 30.0, (img_w, img_h)) for i, data in enumerate(tqdm.tqdm(loader)): imgs, names = data imgs = imgs.cuda() with torch.no_grad(): out = net(imgs) col_sample = np.linspace(0, 800 - 1, cfg.griding_num) col_sample_w = col_sample[1] - col_sample[0] out_j = out[0].data.cpu().numpy() out_j = out_j[:, ::-1, :] prob = scipy.special.softmax(out_j[:-1, :, :], axis=0) idx = np.arange(cfg.griding_num) + 1 idx = idx.reshape(-1, 1, 1) loc = np.sum(prob * idx, axis=0) out_j = np.argmax(out_j, axis=0) loc[out_j == cfg.griding_num] = 0 out_j = loc # import pdb; pdb.set_trace() vis = cv2.imread(os.path.join(cfg.data_root,names[0])) for i in range(out_j.shape[1]): if np.sum(out_j[:, i] != 0) > 2: for k in range(out_j.shape[0]): if out_j[k, i] > 0: ppp = (int(out_j[k, i] * col_sample_w * img_w / 800) - 1, int(img_h * (row_anchor[cls_num_per_lane-1-k]/288)) - 1 ) cv2.circle(vis,ppp,5,(0,255,0),-1) vout.write(vis) vout.release()

这是一个使用PyTorch框架测试模型的代码，代码中导入了许多必要的库以及自定义的模型和数据集等。通过调用PyTorch的后端，启用一些加速技术，然后解析配置参数，并根据数据集类型设置类别数。创建一个模型实例，传入必要的参数并将其转移到GPU上以加速处理。最后进行模型测试。