def main():
device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
print("using {} device.".format(device))
train_images_path, train_images_label, val_images_path, val_images_label = read_split_data(root)
data_transform = {
"train": transforms.Compose([transforms.RandomResizedCrop(224),
transforms.RandomHorizontalFlip(),
transforms.ToTensor(),
transforms.Normalize([0.485, 0.456, 0.406], [0.229, 0.224, 0.225])]),
"val": transforms.Compose([transforms.Resize(256),
transforms.CenterCrop(224),
transforms.ToTensor(),
transforms.Normalize([0.485, 0.456, 0.406], [0.229, 0.224, 0.225])])}
train_data_set = MyDataSet(images_path=train_images_path,
images_class=train_images_label,
transform=data_transform["train"])
batch_size = 8
nw = min([os.cpu_count(), batch_size if batch_size > 1 else 0, 8]) # number of workers
print('Using {} dataloader workers'.format(nw))
train_loader = torch.utils.data.DataLoader(train_data_set,
batch_size=batch_size,
shuffle=True,
num_workers=nw,
collate_fn=train_data_set.collate_fn)
# plot_data_loader_image(train_loader)
for step, data in enumerate(train_loader):
images, labels = data
def main(args):
device = torch.device(args.device if torch.cuda.is_available() else "cpu")
print(args)
print('Start Tensorboard with "tensorboard --logdir=runs", view at http://localhost:6006/')
tb_writer = SummaryWriter()
if os.path.exists("./weights") is False:
os.makedirs("./weights")
train_images_path, train_images_label, val_images_path, val_images_label = read_split_data(args.data_path)
img_size = {"B0": 224,
"B1": 240,
"B2": 260,
"B3": 300,
"B4": 380,
"B5": 456,
"B6": 528,
"B7": 600}
num_model = "B0"
data_transform = {
"train": transforms.Compose([transforms.RandomResizedCrop(img_size[num_model]),
transforms.RandomHorizontalFlip(),
transforms.ToTensor(),
transforms.Normalize([0.485, 0.456, 0.406], [0.229, 0.224, 0.225])]),
"val": transforms.Compose([transforms.Resize(img_size[num_model]),
transforms.CenterCrop(img_size[num_model]),
transforms.ToTensor(),
transforms.Normalize([0.485, 0.456, 0.406], [0.229, 0.224, 0.225])])}
# 实例化训练数据集
train_data_set = MyDataSet(images_path=train_images_path,
images_class=train_images_label,
transform=data_transform["train"])
# 实例化验证数据集
val_data_set = MyDataSet(images_path=val_images_path,
images_class=val_images_label,
transform=data_transform["val"])
batch_size = args.batch_size
nw = min([os.cpu_count(), batch_size if batch_size > 1 else 0, 8]) # number of workers
print('Using {} dataloader workers every process'.format(nw))
train_loader = torch.utils.data.DataLoader(train_data_set,
batch_size=batch_size,
shuffle=True,
pin_memory=True,
num_workers=nw,
collate_fn=train_data_set.collate_fn)
val_loader = torch.utils.data.DataLoader(val_data_set,
batch_size=batch_size,
shuffle=False,
pin_memory=True,
num_workers=nw,
collate_fn=val_data_set.collate_fn)
def main(args):
device = torch.device(args.device if torch.cuda.is_available() else "cpu")
print(f"using device: {device}")
_, _, val_images_path, val_images_label = read_split_data(args.data_path)
img_size = 384
data_transform = {
"val": transforms.Compose([transforms.Resize(int(img_size * 1.143)),
transforms.CenterCrop(img_size),
transforms.ToTensor(),
transforms.Normalize([0.485, 0.456, 0.406], [0.229, 0.224, 0.225])])}
# 实例化验证数据集
val_dataset = MyDataSet(images_path=val_images_path,
images_class=val_images_label,
transform=data_transform["val"])
nw = min([os.cpu_count(), args.batch_size if args.batch_size > 1 else 0, 8]) # number of workers
print('Using {} dataloader workers every process'.format(nw))
val_loader = torch.utils.data.DataLoader(val_dataset,
batch_size=args.batch_size,
shuffle=False,
pin_memory=True,
num_workers=nw,
collate_fn=val_dataset.collate_fn)
model = create_model(num_classes=args.num_classes)
# load pretrain weights
assert os.path.exists(args.weights), "cannot find {} file".format(args.weights)
model.load_state_dict(torch.load(args.weights, map_location=device))
model.to(device)
# read class_indict
json_label_path = './class_indices.json'
assert os.path.exists(json_label_path), "cannot find {} file".format(json_label_path)
json_file = open(json_label_path, 'r')
class_indict = json.load(json_file)
labels = [label for _, label in class_indict.items()]
confusion = ConfusionMatrix(num_classes=args.num_classes, labels=labels)
model.eval()
with torch.no_grad():
for val_data in tqdm(val_loader, file=sys.stdout):
val_images, val_labels = val_data
outputs = model(val_images.to(device))
outputs = torch.softmax(outputs, dim=1)
outputs = torch.argmax(outputs, dim=1)
confusion.update(outputs.to("cpu").numpy(), val_labels.to("cpu").numpy())
confusion.plot()
confusion.summary()
def main(args):
device = torch.device(args.device if torch.cuda.is_available() else "cpu")
print(args)
print(
'Start Tensorboard with "tensorboard --logdir=runs", view at http://localhost:6006/'
)
tb_writer = SummaryWriter()
if os.path.exists("./weights") is False:
os.makedirs("./weights")
train_images_path, train_images_label, val_images_path, val_images_label = read_split_data(
args.data_path)
img_size = {
"B0": 224,
"B1": 240,
"B2": 260,
"B3": 300,
"B4": 380,
"B5": 456,
"B6": 528,
"B7": 600
}
num_model = "B0"
data_transform = {
"train":
transforms.Compose([
transforms.RandomResizedCrop(img_size[num_model]),
transforms.RandomHorizontalFlip(),
transforms.ToTensor(),
transforms.Normalize([0.485, 0.456, 0.406], [0.229, 0.224, 0.225])
]),
"val":
transforms.Compose([
transforms.Resize(img_size[num_model]),
transforms.CenterCrop(img_size[num_model]),
transforms.ToTensor(),
transforms.Normalize([0.485, 0.456, 0.406], [0.229, 0.224, 0.225])
])
}
# 实例化训练数据集
train_data_set = MyDataSet(images_path=train_images_path,
images_class=train_images_label,
transform=data_transform["train"])
# 实例化验证数据集
val_data_set = MyDataSet(images_path=val_images_path,
images_class=val_images_label,
transform=data_transform["val"])
batch_size = args.batch_size
nw = min([os.cpu_count(), batch_size if batch_size > 1 else 0,
8]) # number of workers
print('Using {} dataloader workers every process'.format(nw))
train_loader = torch.utils.data.DataLoader(
train_data_set,
batch_size=batch_size,
shuffle=True,
pin_memory=True,
num_workers=nw,
collate_fn=train_data_set.collate_fn)
val_loader = torch.utils.data.DataLoader(
val_data_set,
batch_size=batch_size,
shuffle=False,
pin_memory=True,
num_workers=nw,
collate_fn=val_data_set.collate_fn)
# 如果存在预训练权重则载入
model = create_model(num_classes=args.num_classes).to(device)
if os.path.exists(args.weights):
weights_dict = torch.load(args.weights, map_location=device)
load_weights_dict = {
k: v
for k, v in weights_dict.items()
if model.state_dict()[k].numel() == v.numel()
}
print(model.load_state_dict(load_weights_dict, strict=False))
# 是否冻结权重
if args.freeze_layers:
for name, para in model.named_parameters():
# 除最后一个卷积层和全连接层外，其他权重全部冻结
if ("features.top" not in name) and ("classifier" not in name):
para.requires_grad_(False)
else:
print("training {}".format(name))
pg = [p for p in model.parameters() if p.requires_grad]
optimizer = optim.SGD(pg, lr=args.lr, momentum=0.9, weight_decay=1E-4)
# Scheduler https://arxiv.org/pdf/1812.01187.pdf
lf = lambda x: ((1 + math.cos(x * math.pi / args.epochs)) / 2) * (
1 - args.lrf) + args.lrf # cosine
scheduler = lr_scheduler.LambdaLR(optimizer, lr_lambda=lf)
for epoch in range(args.epochs):
# train
mean_loss = train_one_epoch(model=model,
optimizer=optimizer,
data_loader=train_loader,
device=device,
epoch=epoch)
scheduler.step()
# validate
sum_num = evaluate(model=model, data_loader=val_loader, device=device)
acc = sum_num / len(val_data_set)
print("[epoch {}] accuracy: {}".format(epoch, round(acc, 3)))
tags = ["loss", "accuracy", "learning_rate"]
tb_writer.add_scalar(tags[0], mean_loss, epoch)
tb_writer.add_scalar(tags[1], acc, epoch)
tb_writer.add_scalar(tags[2], optimizer.param_groups[0]["lr"], epoch)
torch.save(model.state_dict(), "./weights/model-{}.pth".format(epoch))
def main_fun(rank, world_size, args):
if torch.cuda.is_available() is False:
raise EnvironmentError("not find GPU device for training.")
# 初始化各进程环境 start
os.environ["MASTER_ADDR"] = "localhost"
os.environ["MASTER_PORT"] = "12355"
args.rank = rank
args.world_size = world_size
args.gpu = rank
args.distributed = True
torch.cuda.set_device(args.gpu)
args.dist_backend = 'nccl'
print('| distributed init (rank {}): {}'.format(args.rank, args.dist_url),
flush=True)
dist.init_process_group(backend=args.dist_backend,
init_method=args.dist_url,
world_size=args.world_size,
rank=args.rank)
dist.barrier()
# 初始化各进程环境 end
rank = args.rank
device = torch.device(args.device)
batch_size = args.batch_size
num_classes = args.num_classes
weights_path = args.weights
args.lr *= args.world_size # 学习率要根据并行GPU的数量进行倍增
if rank == 0: # 在第一个进程中打印信息，并实例化tensorboard
print(args)
print(
'Start Tensorboard with "tensorboard --logdir=runs", view at http://localhost:6006/'
)
tb_writer = SummaryWriter()
if os.path.exists("./weights") is False:
os.makedirs("./weights")
train_images_path, train_images_label, val_images_path, val_images_label = read_split_data(
args.data_path)
data_transform = {
"train":
transforms.Compose([
transforms.RandomResizedCrop(224),
transforms.RandomHorizontalFlip(),
transforms.ToTensor(),
transforms.Normalize([0.485, 0.456, 0.406], [0.229, 0.224, 0.225])
]),
"val":
transforms.Compose([
transforms.Resize(256),
transforms.CenterCrop(224),
transforms.ToTensor(),
transforms.Normalize([0.485, 0.456, 0.406], [0.229, 0.224, 0.225])
])
}
# 实例化训练数据集
train_data_set = MyDataSet(images_path=train_images_path,
images_class=train_images_label,
transform=data_transform["train"])
# 实例化验证数据集
val_data_set = MyDataSet(images_path=val_images_path,
images_class=val_images_label,
transform=data_transform["val"])
# 给每个rank对应的进程分配训练的样本索引
train_sampler = torch.utils.data.distributed.DistributedSampler(
train_data_set)
val_sampler = torch.utils.data.distributed.DistributedSampler(val_data_set)
# 将样本索引每batch_size个元素组成一个list
train_batch_sampler = torch.utils.data.BatchSampler(train_sampler,
batch_size,
drop_last=True)
nw = min([os.cpu_count(), batch_size if batch_size > 1 else 0,
8]) # number of workers
if rank == 0:
print('Using {} dataloader workers every process'.format(nw))
train_loader = torch.utils.data.DataLoader(
train_data_set,
batch_sampler=train_batch_sampler,
pin_memory=True,
num_workers=nw,
collate_fn=train_data_set.collate_fn)
val_loader = torch.utils.data.DataLoader(
val_data_set,
batch_size=batch_size,
sampler=val_sampler,
pin_memory=True,
num_workers=nw,
collate_fn=val_data_set.collate_fn)
# 实例化模型
model = resnet34(num_classes=num_classes).to(device)
# 如果存在预训练权重则载入
if os.path.exists(weights_path):
weights_dict = torch.load(weights_path, map_location=device)
load_weights_dict = {
k: v
for k, v in weights_dict.items()
if model.state_dict()[k].numel() == v.numel()
}
model.load_state_dict(load_weights_dict, strict=False)
else:
checkpoint_path = os.path.join(tempfile.gettempdir(),
"initial_weights.pt")
# 如果不存在预训练权重，需要将第一个进程中的权重保存，然后其他进程载入，保持初始化权重一致
if rank == 0:
torch.save(model.state_dict(), checkpoint_path)
dist.barrier()
# 这里注意，一定要指定map_location参数，否则会导致第一块GPU占用更多资源
model.load_state_dict(torch.load(checkpoint_path, map_location=device))
# 是否冻结权重
if args.freeze_layers:
for name, para in model.named_parameters():
# 除最后的全连接层外，其他权重全部冻结
if "fc" not in name:
para.requires_grad_(False)
else:
# 只有训练带有BN结构的网络时使用SyncBatchNorm采用意义
if args.syncBN:
# 使用SyncBatchNorm后训练会更耗时
model = torch.nn.SyncBatchNorm.convert_sync_batchnorm(model).to(
device)
# 转为DDP模型
model = torch.nn.parallel.DistributedDataParallel(model,
device_ids=[args.gpu])
# optimizer
pg = [p for p in model.parameters() if p.requires_grad]
optimizer = optim.SGD(pg, lr=args.lr, momentum=0.9, weight_decay=0.005)
# Scheduler https://arxiv.org/pdf/1812.01187.pdf
lf = lambda x: ((1 + math.cos(x * math.pi / args.epochs)) / 2) * (
1 - args.lrf) + args.lrf # cosine
scheduler = lr_scheduler.LambdaLR(optimizer, lr_lambda=lf)
for epoch in range(args.epochs):
train_sampler.set_epoch(epoch)
mean_loss = train_one_epoch(model=model,
optimizer=optimizer,
data_loader=train_loader,
device=device,
epoch=epoch)
scheduler.step()
sum_num = evaluate(model=model, data_loader=val_loader, device=device)
acc = sum_num / val_sampler.total_size
if rank == 0:
print("[epoch {}] accuracy: {}".format(epoch, round(acc, 3)))
tags = ["loss", "accuracy", "learning_rate"]
tb_writer.add_scalar(tags[0], mean_loss, epoch)
tb_writer.add_scalar(tags[1], acc, epoch)
tb_writer.add_scalar(tags[2], optimizer.param_groups[0]["lr"],
epoch)
torch.save(model.module.state_dict(),
"./weights/model-{}.pth".format(epoch))
# 删除临时缓存文件
if rank == 0:
if os.path.exists(checkpoint_path) is True:
os.remove(checkpoint_path)
cleanup()
def main(args):
device = torch.device(args.device if torch.cuda.is_available() else "cpu")
if os.path.exists("./weights") is False:
os.makedirs("./weights")
tb_writer = SummaryWriter()
train_images_path, train_images_label, val_images_path, val_images_label = read_split_data(
args.data_path)
img_size = 224
data_transform = {
"train":
transforms.Compose([
transforms.RandomResizedCrop(img_size),
transforms.RandomHorizontalFlip(),
transforms.ToTensor(),
transforms.Normalize([0.485, 0.456, 0.406], [0.229, 0.224, 0.225])
]),
"val":
transforms.Compose([
transforms.Resize(int(img_size * 1.143)),
transforms.CenterCrop(img_size),
transforms.ToTensor(),
transforms.Normalize([0.485, 0.456, 0.406], [0.229, 0.224, 0.225])
])
}
# 实例化训练数据集
train_dataset = MyDataSet(images_path=train_images_path,
images_class=train_images_label,
transform=data_transform["train"])
# 实例化验证数据集
val_dataset = MyDataSet(images_path=val_images_path,
images_class=val_images_label,
transform=data_transform["val"])
batch_size = args.batch_size
nw = min([os.cpu_count(), batch_size if batch_size > 1 else 0,
8]) # number of workers
print('Using {} dataloader workers every process'.format(nw))
train_loader = torch.utils.data.DataLoader(
train_dataset,
batch_size=batch_size,
shuffle=True,
pin_memory=True,
num_workers=nw,
collate_fn=train_dataset.collate_fn)
val_loader = torch.utils.data.DataLoader(val_dataset,
batch_size=batch_size,
shuffle=False,
pin_memory=True,
num_workers=nw,
collate_fn=val_dataset.collate_fn)
model = create_model(num_classes=args.num_classes).to(device)
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))
if args.freeze_layers:
for name, para in model.named_parameters():
# 除head外，其他权重全部冻结
if "head" not in name:
para.requires_grad_(False)
else:
print("training {}".format(name))
pg = [p for p in model.parameters() if p.requires_grad]
optimizer = optim.AdamW(pg, lr=args.lr, weight_decay=5E-2)
for epoch in range(args.epochs):
# train
train_loss, train_acc = train_one_epoch(model=model,
optimizer=optimizer,
data_loader=train_loader,
device=device,
epoch=epoch)
# validate
val_loss, val_acc = evaluate(model=model,
data_loader=val_loader,
device=device,
epoch=epoch)
tags = [
"train_loss", "train_acc", "val_loss", "val_acc", "learning_rate"
]
tb_writer.add_scalar(tags[0], train_loss, epoch)
tb_writer.add_scalar(tags[1], train_acc, epoch)
tb_writer.add_scalar(tags[2], val_loss, epoch)
tb_writer.add_scalar(tags[3], val_acc, epoch)
tb_writer.add_scalar(tags[4], optimizer.param_groups[0]["lr"], epoch)
torch.save(model.state_dict(), "./weights/model-{}.pth".format(epoch))
def main(args):
device = torch.device(args.device if torch.cuda.is_available() else "cpu")
_, _, val_images_path, val_images_label = read_split_data(args.data_path)
img_size = 384
data_transform = {
"val":
transforms.Compose([
transforms.Resize(int(img_size * 1.143)),
transforms.CenterCrop(img_size),
transforms.ToTensor(),
transforms.Normalize([0.485, 0.456, 0.406], [0.229, 0.224, 0.225])
])
}
# 实例化验证数据集
val_dataset = MyDataSet(images_path=val_images_path,
images_class=val_images_label,
transform=data_transform["val"])
batch_size = args.batch_size
nw = min([os.cpu_count(), batch_size if batch_size > 1 else 0,
8]) # number of workers
print('Using {} dataloader workers every process'.format(nw))
val_loader = torch.utils.data.DataLoader(val_dataset,
batch_size=batch_size,
shuffle=False,
pin_memory=True,
num_workers=nw,
collate_fn=val_dataset.collate_fn)
model = create_model(num_classes=args.num_classes).to(device)
assert os.path.exists(
args.weights), "weights file: '{}' not exist.".format(args.weights)
model.load_state_dict(torch.load(args.weights, map_location=device))
# read class_indict
json_path = './class_indices.json'
assert os.path.exists(json_path), "file: '{}' dose not exist.".format(
json_path)
json_file = open(json_path, "r")
class_indict = json.load(json_file)
model.eval()
with torch.no_grad():
with open("record.txt", "w") as f:
# validate
data_loader = tqdm(val_loader, file=sys.stdout)
for step, data in enumerate(data_loader):
images, labels = data
pred = model(images.to(device))
pred_classes = torch.max(pred, dim=1)[1]
contrast = torch.eq(pred_classes, labels.to(device)).tolist()
labels = labels.tolist()
pred_classes = pred_classes.tolist()
for i, flag in enumerate(contrast):
if flag is False:
file_name = val_images_path[batch_size * step + i]
true_label = class_indict[str(labels[i])]
false_label = class_indict[str(pred_classes[i])]
f.write(
f"{file_name} TrueLabel:{true_label} PredictLabel:{false_label}\n"
)
def main(args):
device = torch.device(args.device if torch.cuda.is_available() else "cpu")
print(args)
print(
'Start Tensorboard with "tensorboard --logdir=runs", view at http://localhost:6006/'
)
tb_writer = SummaryWriter()
if os.path.exists("./weights") is False:
os.makedirs("./weights")
train_images_path, train_images_label, val_images_path, val_images_label = read_split_data(
args.data_path)
data_transform = {
"train":
transforms.Compose([
transforms.RandomResizedCrop(224),
transforms.RandomHorizontalFlip(),
transforms.ToTensor(),
transforms.Normalize([0.485, 0.456, 0.406], [0.229, 0.224, 0.225])
]),
"val":
transforms.Compose([
transforms.Resize(256),
transforms.CenterCrop(224),
transforms.ToTensor(),
transforms.Normalize([0.485, 0.456, 0.406], [0.229, 0.224, 0.225])
])
}
# 实例化训练数据集
train_dataset = MyDataSet(images_path=train_images_path,
images_class=train_images_label,
transform=data_transform["train"])
# 实例化验证数据集
val_dataset = MyDataSet(images_path=val_images_path,
images_class=val_images_label,
transform=data_transform["val"])
batch_size = args.batch_size
nw = min([os.cpu_count(), batch_size if batch_size > 1 else 0,
8]) # number of workers
print('Using {} dataloader workers every process'.format(nw))
train_loader = torch.utils.data.DataLoader(
train_dataset,
batch_size=batch_size,
shuffle=True,
pin_memory=True,
num_workers=nw,
collate_fn=train_dataset.collate_fn)
val_loader = torch.utils.data.DataLoader(val_dataset,
batch_size=batch_size,
shuffle=False,
pin_memory=True,
num_workers=nw,
collate_fn=val_dataset.collate_fn)
# 如果存在预训练权重则载入
model = densenet121(num_classes=args.num_classes).to(device)
if args.weights != "":
if os.path.exists(args.weights):
load_state_dict(model, args.weights)
else:
raise FileNotFoundError("not found weights file: {}".format(
args.weights))
# 是否冻结权重
if args.freeze_layers:
for name, para in model.named_parameters():
# 除最后的全连接层外，其他权重全部冻结
if "classifier" not in name:
para.requires_grad_(False)
pg = [p for p in model.parameters() if p.requires_grad]
optimizer = optim.SGD(pg,
lr=args.lr,
momentum=0.9,
weight_decay=1E-4,
nesterov=True)
# Scheduler https://arxiv.org/pdf/1812.01187.pdf
lf = lambda x: ((1 + math.cos(x * math.pi / args.epochs)) / 2) * (
1 - args.lrf) + args.lrf # cosine
scheduler = lr_scheduler.LambdaLR(optimizer, lr_lambda=lf)
for epoch in range(args.epochs):
# train
mean_loss = train_one_epoch(model=model,
optimizer=optimizer,
data_loader=train_loader,
device=device,
epoch=epoch)
scheduler.step()
# validate
acc = evaluate(model=model, data_loader=val_loader, device=device)
print("[epoch {}] accuracy: {}".format(epoch, round(acc, 3)))
tags = ["loss", "accuracy", "learning_rate"]
tb_writer.add_scalar(tags[0], mean_loss, epoch)
tb_writer.add_scalar(tags[1], acc, epoch)
tb_writer.add_scalar(tags[2], optimizer.param_groups[0]["lr"], epoch)
torch.save(model.state_dict(), "./weights/model-{}.pth".format(epoch))
def main(args):
if torch.cuda.is_available() is False:
raise EnvironmentError("not find GPU device for training.")
# 初始化各进程环境
init_distributed_mode(args=args)
rank = args.rank
device = torch.device(args.device)
batch_size = args.batch_size
num_classes = args.num_classes
weights_path = args.weights
lr = args.lr
if rank == 0: # 在第一个进程中打印信息，并实例化tensorboard
print(args)
print('Start Tensorboard with "tensorboard --logdir=runs", view at http://localhost:6006/')
tb_writer = SummaryWriter()
if os.path.exists("./weights") is False:
os.makedirs("./weights")
train_images_path, train_images_label, val_images_path, val_images_label = read_split_data(root)
data_transform = {
"train": transforms.Compose([transforms.RandomResizedCrop(224),
transforms.RandomHorizontalFlip(),
transforms.ToTensor(),
transforms.Normalize([0.485, 0.456, 0.406], [0.229, 0.224, 0.225])]),
"val": transforms.Compose([transforms.Resize(256),
transforms.CenterCrop(224),
transforms.ToTensor(),
transforms.Normalize([0.485, 0.456, 0.406], [0.229, 0.224, 0.225])])}
# 实例化训练数据集
train_data_set = MyDataSet(images_path=train_images_path,
images_class=train_images_label,
transform=data_transform["train"])
# 实例化验证数据集
val_data_set = MyDataSet(images_path=val_images_path,
images_class=val_images_label,
transform=data_transform["val"])
# 给每个rank对应的进程分配训练的样本索引
train_sampler = torch.utils.data.distributed.DistributedSampler(train_data_set)
val_sampler = torch.utils.data.distributed.DistributedSampler(val_data_set)
# 将样本索引每batch_size个元素组成一个list
train_batch_sampler = torch.utils.data.BatchSampler(
train_sampler, batch_size, drop_last=True)
nw = min([os.cpu_count(), batch_size if batch_size > 1 else 0, 8]) # number of workers
if rank == 0:
print('Using {} dataloader workers every process'.format(nw))
train_loader = torch.utils.data.DataLoader(train_data_set,
batch_sampler=train_batch_sampler,
pin_memory=True,
num_workers=nw,
collate_fn=train_data_set.collate_fn)
val_loader = torch.utils.data.DataLoader(val_data_set,
batch_size=batch_size,
sampler=val_sampler,
pin_memory=True,
num_workers=nw,
collate_fn=val_data_set.collate_fn)
# 实例化模型
model = resnet34(num_classes=num_classes).to(device)
# 如果存在预训练权重则载入
if os.path.exists(weights_path):
weights_dict = torch.load(weights_path, map_location=device)
load_weights_dict = {k: v for k, v in weights_dict.items()
if model.state_dict()[k].numel() == v.numel()}
model.load_state_dict(load_weights_dict, strict=False)
else:
# 如果不存在预训练权重，需要将第一个进程中的权重保存，然后其他进程载入，保持初始化权重一致
if rank == 0:
torch.save(model.state_dict(), "./initial_weights.pt")
dist.barrier()
model.load_state_dict(torch.load("./initial_weights.pt"))
# 是否冻结权重
if args.freeze_layers:
for name, para in model.named_parameters():
# 除最后的全连接层外，其他权重全部冻结
if "fc" not in name:
para.requires_grad_(False)
else:
model = torch.nn.SyncBatchNorm.convert_sync_batchnorm(model).to(device)
# 转为DDP模型
model = torch.nn.parallel.DistributedDataParallel(model, device_ids=[args.gpu])
# optimizer
pg = [p for p in model.parameters() if p.requires_grad]
optimizer = optim.Adam(pg, lr=lr)
for epoch in range(args.epochs):
train_sampler.set_epoch(epoch)
mean_loss = train_one_epoch(model=model,
optimizer=optimizer,
data_loader=train_loader,
device=device,
epoch=epoch)
sum_num = evaluate(model=model,
data_loader=val_loader,
device=device)
acc = sum_num / val_sampler.total_size
if rank == 0:
tags = ["loss", "accuracy"]
tb_writer.add_scalar(tags[0], mean_loss, epoch)
tb_writer.add_scalar(tags[1], acc, epoch)
torch.save(model.state_dict(), "./weights/model-{}.pth".format(epoch))
def main(args):
device = torch.device(args.device if torch.cuda.is_available() else "cpu")
if os.path.exists("./weights") is False:
os.makedirs("./weights")
tb_writer = SummaryWriter()
train_images_path, train_images_label, val_images_path, val_images_label = read_split_data(
args.data_path)
data_transform = {
"train":
transforms.Compose([
transforms.RandomResizedCrop(224),
transforms.RandomHorizontalFlip(),
transforms.ToTensor(),
transforms.Normalize([0.5, 0.5, 0.5], [0.5, 0.5, 0.5])
]),
"val":
transforms.Compose([
transforms.Resize(256),
transforms.CenterCrop(224),
transforms.ToTensor(),
transforms.Normalize([0.5, 0.5, 0.5], [0.5, 0.5, 0.5])
])
}
# 实例化训练数据集
train_dataset = MyDataSet(images_path=train_images_path,
images_class=train_images_label,
transform=data_transform["train"])
# 实例化验证数据集
val_dataset = MyDataSet(images_path=val_images_path,
images_class=val_images_label,
transform=data_transform["val"])
batch_size = args.batch_size
nw = min([os.cpu_count(), batch_size if batch_size > 1 else 0,
8]) # number of workers
print('Using {} dataloader workers every process'.format(nw))
train_loader = torch.utils.data.DataLoader(
train_dataset,
batch_size=batch_size,
shuffle=True,
pin_memory=True,
num_workers=nw,
collate_fn=train_dataset.collate_fn)
val_loader = torch.utils.data.DataLoader(val_dataset,
batch_size=batch_size,
shuffle=False,
pin_memory=True,
num_workers=nw,
collate_fn=val_dataset.collate_fn)
model = create_model(num_classes=5, has_logits=False).to(device)
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)
# 删除不需要的权重
del_keys = ['head.weight', 'head.bias'] if model.has_logits \
else ['pre_logits.fc.weight', 'pre_logits.fc.bias', 'head.weight', 'head.bias']
for k in del_keys:
del weights_dict[k]
print(model.load_state_dict(weights_dict, strict=False))
if args.freeze_layers:
for name, para in model.named_parameters():
# 除head, pre_logits外，其他权重全部冻结
if "head" not in name and "pre_logits" not in name:
para.requires_grad_(False)
else:
print("training {}".format(name))
pg = [p for p in model.parameters() if p.requires_grad]
optimizer = optim.SGD(pg, lr=args.lr, momentum=0.9, weight_decay=5E-5)
# Scheduler https://arxiv.org/pdf/1812.01187.pdf
lf = lambda x: ((1 + math.cos(x * math.pi / args.epochs)) / 2) * (
1 - args.lrf) + args.lrf # cosine
scheduler = lr_scheduler.LambdaLR(optimizer, lr_lambda=lf)
for epoch in range(args.epochs):
# train
train_loss, train_acc = train_one_epoch(model=model,
optimizer=optimizer,
data_loader=train_loader,
device=device,
epoch=epoch)
scheduler.step()
# validate
val_loss, val_acc = evaluate(model=model,
data_loader=val_loader,
device=device,
epoch=epoch)
tags = [
"train_loss", "train_acc", "val_loss", "val_acc", "learning_rate"
]
tb_writer.add_scalar(tags[0], train_loss, epoch)
tb_writer.add_scalar(tags[1], train_acc, epoch)
tb_writer.add_scalar(tags[2], val_loss, epoch)
tb_writer.add_scalar(tags[3], val_acc, epoch)
tb_writer.add_scalar(tags[4], optimizer.param_groups[0]["lr"], epoch)
torch.save(model.state_dict(), "./weights/model-{}.pth".format(epoch))
