|
|
@@ -0,0 +1,292 @@
|
|
|
+# 微调pytorch的预训练模型,在自己的数据上训练,完成分类任务。
|
|
|
+import time
|
|
|
+
|
|
|
+import torch
|
|
|
+import torch.nn as nn
|
|
|
+import torch.optim as optim
|
|
|
+from torch.utils.data import DataLoader
|
|
|
+import torchvision.transforms as transforms
|
|
|
+from torchvision.datasets import ImageFolder
|
|
|
+from torchvision.models import resnet18, ResNet18_Weights,resnet50,ResNet50_Weights, squeezenet1_0, SqueezeNet1_0_Weights,\
|
|
|
+ shufflenet_v2_x1_0, ShuffleNet_V2_X1_0_Weights, swin_v2_s, Swin_V2_S_Weights, swin_v2_b, Swin_V2_B_Weights
|
|
|
+import matplotlib.pyplot as plt
|
|
|
+import numpy as np
|
|
|
+from torch.utils.tensorboard import SummaryWriter # 添加 TensorBoard 支持
|
|
|
+from datetime import datetime
|
|
|
+import os
|
|
|
+os.environ['CUDA_VISIBLE_DEVICES'] = '1'
|
|
|
+
|
|
|
+class Trainer:
|
|
|
+ def __init__(self, batch_size, train_dir, val_dir, name, checkpoint):
|
|
|
+ # 初始化 TensorBoard writer
|
|
|
+ self.name = name
|
|
|
+ self.checkpoint = checkpoint
|
|
|
+ # 获取当前时间戳
|
|
|
+ timestamp = datetime.now().strftime("%Y%m%d-%H%M%S")
|
|
|
+ log_dir = f'runs/turbidity_{self.name}_{timestamp}'
|
|
|
+ self.writer = SummaryWriter(log_dir)
|
|
|
+
|
|
|
+ # 定义数据增强和处理
|
|
|
+ self.train_transforms = transforms.Compose([
|
|
|
+ transforms.Resize((256, 256)), # 调整图像大小为256x256 (ResNet输入尺寸)
|
|
|
+ transforms.RandomHorizontalFlip(p=0.5), # 随机水平翻转,增加数据多样性
|
|
|
+ transforms.RandomRotation(10), # 随机旋转±10度
|
|
|
+ transforms.ColorJitter(brightness=0.1, contrast=0.1, saturation=0, hue=0), # 颜色抖动
|
|
|
+ transforms.ToTensor(), # 转换为tensor并归一化到[0,1]
|
|
|
+ transforms.Normalize(mean=[0.485, 0.456, 0.406], std=[0.229, 0.224, 0.225]) # ImageNet标准化
|
|
|
+ ])
|
|
|
+
|
|
|
+ # 测试集基础变换
|
|
|
+ self.val_transforms = transforms.Compose([
|
|
|
+ transforms.Resize((256, 256)),
|
|
|
+ transforms.ToTensor(),
|
|
|
+ transforms.Normalize(mean=[0.485, 0.456, 0.406], std=[0.229, 0.224, 0.225])
|
|
|
+ ])
|
|
|
+
|
|
|
+ # 创建数据集对象
|
|
|
+ self.train_dataset = ImageFolder(root=train_dir, transform=self.train_transforms)
|
|
|
+ self.val_dataset = ImageFolder(root=val_dir, transform=self.val_transforms)
|
|
|
+
|
|
|
+ # 创建数据加载器 (Windows环境下设置num_workers=0避免多进程问题)
|
|
|
+ self.batch_size = batch_size
|
|
|
+ self.train_loader = DataLoader(self.train_dataset, batch_size=batch_size, shuffle=True, num_workers=10)
|
|
|
+ self.val_loader = DataLoader(self.val_dataset, batch_size=batch_size, shuffle=False, num_workers=10)
|
|
|
+ # 获取类别数量
|
|
|
+ self.num_classes = len(self.train_dataset.classes)
|
|
|
+ print(f"发现 {self.num_classes} 个类别: {self.train_dataset.classes}")
|
|
|
+
|
|
|
+ # 加载模型
|
|
|
+ if name == 'resnet50':
|
|
|
+ self.weights = ResNet50_Weights.IMAGENET1K_V2
|
|
|
+ self.model = resnet50(weights=self.weights)
|
|
|
+ elif name == 'squeezenet':
|
|
|
+ self.weights = SqueezeNet1_0_Weights.IMAGENET1K_V1
|
|
|
+ self.model = squeezenet1_0(weights=self.weights)
|
|
|
+ elif name == 'shufflenet':
|
|
|
+ self.weights = ShuffleNet_V2_X1_0_Weights.IMAGENET1K_V1
|
|
|
+ self.model = shufflenet_v2_x1_0(weights=self.weights)
|
|
|
+ elif name == 'swin_v2_s':
|
|
|
+ self.weights = Swin_V2_S_Weights.IMAGENET1K_V1
|
|
|
+ self.model = swin_v2_s(weights=self.weights)
|
|
|
+ elif name == 'swin_v2_b':
|
|
|
+ self.weights = Swin_V2_B_Weights.IMAGENET1K_V1
|
|
|
+ self.model = swin_v2_b(weights=self.weights)
|
|
|
+ else:
|
|
|
+ raise ValueError(f"Invalid model name: {name}")
|
|
|
+ print(self.model)
|
|
|
+ # 冻结特征提取层,只训练最后几层,
|
|
|
+ for param in self.model.parameters():
|
|
|
+ param.requires_grad = False
|
|
|
+
|
|
|
+ # 替换最后的分类层以适应新的分类任务
|
|
|
+ if hasattr(self.model, 'fc'):
|
|
|
+ # ResNet系列模型
|
|
|
+ self.model.fc = nn.Sequential(
|
|
|
+ nn.Linear(int(self.model.fc.in_features), int(self.model.fc.in_features) // 2, bias=True),
|
|
|
+ nn.ReLU(inplace=True),
|
|
|
+ nn.Dropout(0.5),
|
|
|
+ nn.Linear(int(self.model.fc.in_features) // 2, self.num_classes, bias=False)
|
|
|
+ )
|
|
|
+ elif hasattr(self.model, 'classifier'):
|
|
|
+ # Swin Transformer等模型
|
|
|
+ self.model.classifier = nn.Sequential(
|
|
|
+ nn.Linear(int(self.model.classifier.in_features), int(self.model.classifier.in_features) // 2,
|
|
|
+ bias=True),
|
|
|
+ nn.ReLU(inplace=True),
|
|
|
+ nn.Dropout(0.5),
|
|
|
+ nn.Linear(int(self.model.classifier.in_features) // 2, self.num_classes, bias=False)
|
|
|
+ )
|
|
|
+ elif hasattr(self.model, 'head'):
|
|
|
+ # Swin Transformer使用head层
|
|
|
+ in_features = self.model.head.in_features
|
|
|
+ self.model.head = nn.Sequential(
|
|
|
+ nn.Linear(int(in_features), int(in_features) // 2, bias=True),
|
|
|
+ nn.ReLU(inplace=True),
|
|
|
+ nn.Dropout(0.5),
|
|
|
+ nn.Linear(int(in_features) // 2, self.num_classes, bias=False)
|
|
|
+ )
|
|
|
+ else:
|
|
|
+ raise ValueError(f"Model {name} does not have recognizable classifier layer")
|
|
|
+
|
|
|
+ # 将模型移动到GPU
|
|
|
+ self.device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
|
|
|
+ self.model = self.model.to(self.device)
|
|
|
+
|
|
|
+ # 定义损失函数
|
|
|
+ self.loss = nn.CrossEntropyLoss() # 多分类常用的交叉熵损失
|
|
|
+
|
|
|
+ # 定义优化器
|
|
|
+ # 只更新requires_grad=True的参数
|
|
|
+ self.optimizer = optim.Adam(self.model.parameters(), lr=1e-3, weight_decay=1e-4)
|
|
|
+
|
|
|
+ # 基于验证损失动态调整,更智能
|
|
|
+ self.scheduler = optim.lr_scheduler.ReduceLROnPlateau(
|
|
|
+ self.optimizer, mode='min', factor=0.5, patience=5, min_lr=1e-7
|
|
|
+ )
|
|
|
+
|
|
|
+ def train_model(self):
|
|
|
+ """
|
|
|
+ 单轮训练函数
|
|
|
+
|
|
|
+ Args:
|
|
|
+
|
|
|
+ Returns:
|
|
|
+ average_loss: 平均损失
|
|
|
+ accuracy: 准确率
|
|
|
+ """
|
|
|
+ self.model.train() # 设置模型为训练模式(启用dropout/batchnorm等)
|
|
|
+ running_loss = 0.0
|
|
|
+ correct_predictions = 0
|
|
|
+ total_samples = 0
|
|
|
+
|
|
|
+ # 遍历训练数据
|
|
|
+ for inputs, labels in self.train_loader:
|
|
|
+ # 将数据移到指定设备上
|
|
|
+ inputs = inputs.to(self.device)
|
|
|
+ labels = labels.to(self.device)
|
|
|
+
|
|
|
+ # 清零梯度缓存
|
|
|
+ self.optimizer.zero_grad()
|
|
|
+
|
|
|
+ # 前向传播
|
|
|
+ outputs = self.model(inputs)
|
|
|
+ loss = self.loss(outputs, labels)
|
|
|
+
|
|
|
+ # 反向传播
|
|
|
+ loss.backward()
|
|
|
+
|
|
|
+ # 更新参数
|
|
|
+ self.optimizer.step()
|
|
|
+
|
|
|
+ # 统计信息
|
|
|
+ running_loss += loss.item() * inputs.size(0)
|
|
|
+ _, predicted = torch.max(outputs.data, 1)
|
|
|
+ total_samples += labels.size(0)
|
|
|
+ correct_predictions += (predicted == labels).sum().item()
|
|
|
+
|
|
|
+ epoch_loss = running_loss / len(self.train_loader.dataset)
|
|
|
+ epoch_acc = correct_predictions / total_samples
|
|
|
+ return epoch_loss, epoch_acc
|
|
|
+
|
|
|
+
|
|
|
+ def validate_model(self):
|
|
|
+ """
|
|
|
+ 验证模型性能
|
|
|
+
|
|
|
+ Args:
|
|
|
+ Returns:
|
|
|
+ average_loss: 平均损失
|
|
|
+ accuracy: 准确率
|
|
|
+ """
|
|
|
+ self.model.eval() # 设置模型为评估模式(关闭dropout/batchnorm等)
|
|
|
+
|
|
|
+ running_loss = 0.0
|
|
|
+ correct_predictions = 0
|
|
|
+ total_samples = 0
|
|
|
+
|
|
|
+ # 不计算梯度,提高推理速度
|
|
|
+ with torch.no_grad():
|
|
|
+ for inputs, labels in self.val_loader:
|
|
|
+ inputs = inputs.to(self.device)
|
|
|
+ labels = labels.to(self.device)
|
|
|
+
|
|
|
+ outputs = self.model(inputs)
|
|
|
+ loss = self.loss(outputs, labels)
|
|
|
+
|
|
|
+ running_loss += loss.item() * inputs.size(0)
|
|
|
+ _, predicted = torch.max(outputs.data, 1)
|
|
|
+ total_samples += labels.size(0)
|
|
|
+ correct_predictions += (predicted == labels).sum().item()
|
|
|
+
|
|
|
+ epoch_loss = running_loss / len(self.val_loader.dataset)
|
|
|
+ epoch_acc = correct_predictions / total_samples
|
|
|
+
|
|
|
+ return epoch_loss, epoch_acc
|
|
|
+
|
|
|
+
|
|
|
+ def train_and_validate(self, num_epochs=25):
|
|
|
+ """
|
|
|
+ 训练和验证
|
|
|
+
|
|
|
+ Args:
|
|
|
+ num_epochs: 训练轮数
|
|
|
+
|
|
|
+ Returns:
|
|
|
+ train_losses: 每轮训练损失
|
|
|
+ train_accuracies: 每轮训练准确率
|
|
|
+ val_losses: 每轮验证损失
|
|
|
+ val_accuracies: 每轮验证准确率
|
|
|
+ """
|
|
|
+ # 存储训练过程中的指标
|
|
|
+ train_losses = []
|
|
|
+ train_accuracies = []
|
|
|
+ val_losses = []
|
|
|
+ val_accuracies = []
|
|
|
+
|
|
|
+ best_val_acc = 0.0
|
|
|
+ best_val_loss = float('inf')
|
|
|
+
|
|
|
+ print("开始训练...")
|
|
|
+ for epoch in range(num_epochs):
|
|
|
+ print(f'Epoch {epoch + 1}/{num_epochs}')
|
|
|
+ print('-' * 20)
|
|
|
+
|
|
|
+ # 训练阶段
|
|
|
+ train_loss, train_acc = self.train_model()
|
|
|
+ print(f'Train Loss: {train_loss:.4f} Acc: {train_acc:.4f}')
|
|
|
+
|
|
|
+ # 验证阶段
|
|
|
+ val_loss, val_acc = self.validate_model()
|
|
|
+ print(f'Val Loss: {val_loss:.4f} Acc: {val_acc:.4f}')
|
|
|
+
|
|
|
+ # 学习率调度
|
|
|
+ self.scheduler.step(val_loss)
|
|
|
+
|
|
|
+ # 记录指标到 TensorBoard
|
|
|
+ self.writer.add_scalar('Loss/Train', train_loss, epoch)
|
|
|
+ self.writer.add_scalar('Loss/Validation', val_loss, epoch)
|
|
|
+ self.writer.add_scalar('Accuracy/Train', train_acc, epoch)
|
|
|
+ self.writer.add_scalar('Accuracy/Validation', val_acc, epoch)
|
|
|
+ self.writer.add_scalar('Learning Rate', self.scheduler.get_last_lr()[0], epoch)
|
|
|
+
|
|
|
+ # 记录指标
|
|
|
+ train_losses.append(train_loss)
|
|
|
+ train_accuracies.append(train_acc)
|
|
|
+ val_losses.append(val_loss)
|
|
|
+ val_accuracies.append(val_acc)
|
|
|
+
|
|
|
+ # 保存最佳模型 (基于验证准确率)
|
|
|
+ if val_acc > best_val_acc:
|
|
|
+ best_val_acc = val_acc
|
|
|
+ torch.save(self.model.state_dict(), f'{self.name}_best_model_acc.pth')
|
|
|
+ print(f"保存了新的最佳准确率模型,验证准确率: {best_val_acc:.4f}")
|
|
|
+
|
|
|
+ # 保存最低验证损失模型
|
|
|
+
|
|
|
+ if val_loss < best_val_loss:
|
|
|
+ best_val_loss = val_loss
|
|
|
+ torch.save(self.model.state_dict(), f'{self.name}_best_model_loss.pth')
|
|
|
+ print(f"保存了新的最低损失模型,验证损失: {best_val_loss:.4f}")
|
|
|
+
|
|
|
+
|
|
|
+ # 关闭 TensorBoard writer
|
|
|
+ self.writer.close()
|
|
|
+
|
|
|
+ print(f"训练完成! 最佳验证准确率: {best_val_acc:.4f}, 最低验证损失: {best_val_loss:.4f}")
|
|
|
+ return train_losses, train_accuracies, val_losses, val_accuracies
|
|
|
+
|
|
|
+if __name__ == '__main__':
|
|
|
+ # 开始训练
|
|
|
+ import argparse
|
|
|
+ parser = argparse.ArgumentParser('预训练模型调参')
|
|
|
+ parser.add_argument('--train_dir',default='./label_data/train',help='help')
|
|
|
+ parser.add_argument('--val_dir', default='./label_data/test',help='help')
|
|
|
+ parser.add_argument('--model', default='resnet18',help='help')
|
|
|
+ args = parser.parse_args()
|
|
|
+ num_epochs = 100
|
|
|
+ trainer = Trainer(batch_size=64,
|
|
|
+ train_dir=args.train_dir,
|
|
|
+ val_dir=args.val_dir,
|
|
|
+ name=args.model,
|
|
|
+ checkpoint=False)
|
|
|
+ train_losses, train_accuracies, val_losses, val_accuracies = trainer.train_and_validate(num_epochs)
|