调用任意框架,完成对tiny-imagenet的训练过程和分类预测
时间: 2024-01-21 20:20:13 浏览: 188
好的,我以PyTorch框架为例,给出对tiny-imagenet的训练过程和分类预测。首先,需要下载并解压tiny-imagenet数据集,然后将其划分为训练集、验证集和测试集。这里我假设数据集已经准备好了。
### 训练过程
1. 导入必要的库
```python
import torch
import torch.nn as nn
import torch.optim as optim
import torchvision
import torchvision.transforms as transforms
```
2. 定义数据增强和预处理
```python
transform_train = transforms.Compose([
transforms.RandomCrop(64, padding=4),
transforms.RandomHorizontalFlip(),
transforms.ToTensor(),
transforms.Normalize((0.5, 0.5, 0.5), (0.5, 0.5, 0.5))
])
transform_test = transforms.Compose([
transforms.ToTensor(),
transforms.Normalize((0.5, 0.5, 0.5), (0.5, 0.5, 0.5))
])
```
3. 加载数据集
```python
trainset = torchvision.datasets.ImageFolder(root='./tiny-imagenet-200/train', transform=transform_train)
trainloader = torch.utils.data.DataLoader(trainset, batch_size=128, shuffle=True, num_workers=2)
valset = torchvision.datasets.ImageFolder(root='./tiny-imagenet-200/val', transform=transform_test)
valloader = torch.utils.data.DataLoader(valset, batch_size=128, shuffle=False, num_workers=2)
```
4. 定义模型
```python
class Net(nn.Module):
def __init__(self):
super(Net, self).__init__()
self.features = nn.Sequential(
nn.Conv2d(3, 64, kernel_size=3, stride=1, padding=1),
nn.BatchNorm2d(64),
nn.ReLU(inplace=True),
nn.Conv2d(64, 128, kernel_size=3, stride=1, padding=1),
nn.BatchNorm2d(128),
nn.ReLU(inplace=True),
nn.MaxPool2d(kernel_size=2, stride=2),
nn.Conv2d(128, 256, kernel_size=3, stride=1, padding=1),
nn.BatchNorm2d(256),
nn.ReLU(inplace=True),
nn.Conv2d(256, 256, kernel_size=3, stride=1, padding=1),
nn.BatchNorm2d(256),
nn.ReLU(inplace=True),
nn.MaxPool2d(kernel_size=2, stride=2),
nn.Conv2d(256, 512, kernel_size=3, stride=1, padding=1),
nn.BatchNorm2d(512),
nn.ReLU(inplace=True),
nn.Conv2d(512, 512, kernel_size=3, stride=1, padding=1),
nn.BatchNorm2d(512),
nn.ReLU(inplace=True),
nn.MaxPool2d(kernel_size=2, stride=2)
)
self.classifier = nn.Sequential(
nn.Linear(512 * 8 * 8, 1024),
nn.ReLU(inplace=True),
nn.Dropout(),
nn.Linear(1024, 1024),
nn.ReLU(inplace=True),
nn.Dropout(),
nn.Linear(1024, 200)
)
def forward(self, x):
x = self.features(x)
x = x.view(-1, 512 * 8 * 8)
x = self.classifier(x)
return x
```
5. 定义优化器和损失函数
```python
net = Net()
net = net.cuda()
criterion = nn.CrossEntropyLoss()
optimizer = optim.SGD(net.parameters(), lr=0.1, momentum=0.9, weight_decay=5e-4)
scheduler = optim.lr_scheduler.MultiStepLR(optimizer, milestones=[60, 120, 160], gamma=0.2)
```
6. 训练模型
```python
for epoch in range(200): # 训练200个epoch
net.train()
train_loss = 0.0
correct = 0
total = 0
for i, data in enumerate(trainloader, 0):
inputs, labels = data
inputs = inputs.cuda()
labels = labels.cuda()
optimizer.zero_grad()
outputs = net(inputs)
loss = criterion(outputs, labels)
loss.backward()
optimizer.step()
train_loss += loss.item()
_, predicted = outputs.max(1)
total += labels.size(0)
correct += predicted.eq(labels).sum().item()
train_acc = 100.0 * correct / total
train_loss /= len(trainloader)
net.eval()
val_loss = 0.0
correct = 0
total = 0
with torch.no_grad():
for data in valloader:
inputs, labels = data
inputs = inputs.cuda()
labels = labels.cuda()
outputs = net(inputs)
loss = criterion(outputs, labels)
val_loss += loss.item()
_, predicted = outputs.max(1)
total += labels.size(0)
correct += predicted.eq(labels).sum().item()
val_acc = 100.0 * correct / total
val_loss /= len(valloader)
scheduler.step()
print('[Epoch %d] Train Loss: %.3f | Train Acc: %.3f%% | Val Loss: %.3f | Val Acc: %.3f%%' %
(epoch + 1, train_loss, train_acc, val_loss, val_acc))
```
### 分类预测
1. 加载测试集数据
```python
testset = torchvision.datasets.ImageFolder(root='./tiny-imagenet-200/test', transform=transform_test)
testloader = torch.utils.data.DataLoader(testset, batch_size=128, shuffle=False, num_workers=2)
```
2. 定义预测函数
```python
def predict(net, testloader):
net.eval()
predictions = []
with torch.no_grad():
for data in testloader:
inputs, _ = data
inputs = inputs.cuda()
outputs = net(inputs)
_, predicted = outputs.max(1)
predictions += predicted.cpu().tolist()
return predictions
```
3. 加载训练好的模型并进行预测
```python
net.load_state_dict(torch.load('tiny-imagenet-200.pth'))
predictions = predict(net, testloader)
```
至此,我们完成了对tiny-imagenet的训练和分类预测。
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