调用任意框架,完成对tiny-imagenet的训练过程和分类预测
时间: 2024-02-27 09:53:06 浏览: 180
Mini-Image Net 的训练与测试数据集
好的,下面我以PyTorch框架为例,演示如何使用该框架完成Tiny-ImageNet的训练和分类预测。
首先,需要下载Tiny-ImageNet数据集,可以从官网上下载并解压。接下来,我们可以使用PyTorch提供的Dataset和DataLoader类来加载数据集。代码如下:
```python
import torch
import torchvision.transforms as transforms
from torchvision.datasets import ImageFolder
from torch.utils.data import DataLoader
# 定义数据预处理的转换
transform_train = transforms.Compose([
transforms.RandomCrop(64, padding=4),
transforms.RandomHorizontalFlip(),
transforms.ToTensor(),
transforms.Normalize(mean=[0.485, 0.456, 0.406],
std=[0.229, 0.224, 0.225])
])
transform_test = transforms.Compose([
transforms.ToTensor(),
transforms.Normalize(mean=[0.485, 0.456, 0.406],
std=[0.229, 0.224, 0.225])
])
# 加载训练集和验证集
train_set = ImageFolder('tiny-imagenet-200/train', transform=transform_train)
train_loader = DataLoader(train_set, batch_size=64, shuffle=True, num_workers=4)
val_set = ImageFolder('tiny-imagenet-200/val', transform=transform_test)
val_loader = DataLoader(val_set, batch_size=64, shuffle=False, num_workers=4)
# 加载类别标签
with open('tiny-imagenet-200/wnids.txt', 'r') as f:
class_names = sorted([line.strip() for line in f.readlines()])
```
接下来,我们可以定义一个卷积神经网络模型,并使用SGD算法进行优化。代码如下:
```python
import torch.nn as nn
import torch.optim as optim
# 定义卷积神经网络模型
class Net(nn.Module):
def __init__(self):
super(Net, self).__init__()
self.conv1 = nn.Conv2d(3, 32, kernel_size=3, stride=1, padding=1)
self.bn1 = nn.BatchNorm2d(32)
self.relu1 = nn.ReLU(inplace=True)
self.pool1 = nn.MaxPool2d(kernel_size=2, stride=2)
self.conv2 = nn.Conv2d(32, 64, kernel_size=3, stride=1, padding=1)
self.bn2 = nn.BatchNorm2d(64)
self.relu2 = nn.ReLU(inplace=True)
self.pool2 = nn.MaxPool2d(kernel_size=2, stride=2)
self.conv3 = nn.Conv2d(64, 128, kernel_size=3, stride=1, padding=1)
self.bn3 = nn.BatchNorm2d(128)
self.relu3 = nn.ReLU(inplace=True)
self.pool3 = nn.MaxPool2d(kernel_size=2, stride=2)
self.fc1 = nn.Linear(128 * 8 * 8, 1024)
self.relu4 = nn.ReLU(inplace=True)
self.drop1 = nn.Dropout(p=0.5)
self.fc2 = nn.Linear(1024, 200)
def forward(self, x):
x = self.conv1(x)
x = self.bn1(x)
x = self.relu1(x)
x = self.pool1(x)
x = self.conv2(x)
x = self.bn2(x)
x = self.relu2(x)
x = self.pool2(x)
x = self.conv3(x)
x = self.bn3(x)
x = self.relu3(x)
x = self.pool3(x)
x = x.view(-1, 128 * 8 * 8)
x = self.fc1(x)
x = self.relu4(x)
x = self.drop1(x)
x = self.fc2(x)
return x
# 定义损失函数和优化器
criterion = nn.CrossEntropyLoss()
optimizer = optim.SGD(net.parameters(), lr=0.1, momentum=0.9, weight_decay=5e-4)
```
在模型训练过程中,我们可以使用训练集对模型进行训练,并使用验证集来评估模型性能。代码如下:
```python
# 定义模型训练函数
def train(net, train_loader, criterion, optimizer, epoch):
net.train()
train_loss = 0
correct = 0
total = 0
for batch_idx, (inputs, targets) in enumerate(train_loader):
inputs, targets = inputs.cuda(), targets.cuda()
optimizer.zero_grad()
outputs = net(inputs)
loss = criterion(outputs, targets)
loss.backward()
optimizer.step()
train_loss += loss.item()
_, predicted = outputs.max(1)
total += targets.size(0)
correct += predicted.eq(targets).sum().item()
print('Epoch: %d, Train Loss: %.3f, Train Acc: %.3f%% (%d/%d)' %
(epoch, train_loss / len(train_loader), 100. * correct / total, correct, total))
# 定义模型验证函数
def validate(net, val_loader, criterion):
net.eval()
val_loss = 0
correct = 0
total = 0
with torch.no_grad():
for batch_idx, (inputs, targets) in enumerate(val_loader):
inputs, targets = inputs.cuda(), targets.cuda()
outputs = net(inputs)
loss = criterion(outputs, targets)
val_loss += loss.item()
_, predicted = outputs.max(1)
total += targets.size(0)
correct += predicted.eq(targets).sum().item()
print('Val Loss: %.3f, Val Acc: %.3f%% (%d/%d)' %
(val_loss / len(val_loader), 100. * correct / total, correct, total))
# 开始模型训练
net.cuda()
for epoch in range(100):
train(net, train_loader, criterion, optimizer, epoch)
validate(net, val_loader, criterion)
```
最后,我们可以使用训练好的模型对测试集进行分类预测,并输出预测结果。代码如下:
```python
# 加载测试集
test_set = ImageFolder('tiny-imagenet-200/test', transform=transform_test)
test_loader = DataLoader(test_set, batch_size=64, shuffle=False, num_workers=4)
# 对测试集进行分类预测
net.eval()
test_preds = []
with torch.no_grad():
for batch_idx, (inputs, targets) in enumerate(test_loader):
inputs = inputs.cuda()
outputs = net(inputs)
_, predicted = outputs.max(1)
test_preds.extend(predicted.cpu().numpy())
# 输出预测结果
with open('tiny-imagenet-200/val/val_annotations.txt', 'r') as f:
lines = f.readlines()
class_to_idx = {class_names[i]: i for i in range(len(class_names))}
idx_to_class = {i: class_names[i] for i in range(len(class_names))}
test_filenames = [line.split()[0] for line in lines]
test_labels = [class_to_idx[line.split()[1]] for line in lines]
test_acc = sum([1 if pred == true_label else 0 for pred, true_label in zip(test_preds, test_labels)]) / len(test_labels)
print('Test Acc: %.3f%% (%d/%d)' % (100. * test_acc, sum([1 if pred == true_label else 0 for pred, true_label in zip(test_preds, test_labels)]), len(test_labels)))
```
以上就是使用PyTorch框架完成Tiny-ImageNet的训练和分类预测的完整代码。注意,由于数据集较大,训练和预测可能需要较长时间。
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