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def flops(self): flops = 0 H, W = self.input_resolution T = self.num_frames ## just count the FLOPs of q@k and attn@v # norm1 # flops += self.dim * H * W # W-MSA/SW-MSA nW = H * W / self.window_size / self.window_size if self.t_attn: flops += nW * self.attn.flops(self.window_size * self.window_size, T, temporal=True) flops += nW * self.attn.flops(self.window_size * self.window_size, T, temporal=False) # mlp # flops += 2 * H * W * self.dim * self.dim * self.mlp_ratio # norm2 # flops += self.dim * H * W return flops

时间: 2023-06-19 19:06:52 浏览: 320
这段代码实现了一个计算模型 FLOPs 的方法。FLOPs 是衡量模型计算量的指标,代表模型所需的浮点运算次数。在这个方法中,首先初始化 FLOPs 为0,然后根据输入分辨率、帧数、窗口大小以及是否有时间注意力,计算出注意力机制的 FLOPs 和 MLP 的 FLOPs,并返回它们的总和。此外,注释掉的代码是计算归一化操作的 FLOPs,但是在这个方法中并没有被计算。
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def flops(self): flops = 0 flops += self.patch_embed.flops() for i, layer in enumerate(self.layers): flops += layer.flops() # flops += self.num_features * self.patches_resolution[0] * self.patches_resolution[1] // (2 ** self.num_layers) # flops += self.num_features * self.num_classes return flops

这是一个类中的方法,用于计算模型的 FLOPs(floating-point operations,即浮点运算量),可以用于评估模型的计算复杂度。具体实现中,首先计算输入图像的 Patch Embedding 的 FLOPs,然后循环遍历所有的 Transformer 层,计算每一层的 FLOPs 并累加到总的 FLOPs 中。最后,还可以选择性地加上最后一层全连接层的计算 FLOPs。

def flops(self, N, T, temporal=False): # calculate flops for 1 window with token length of N flops = 0 # qkv = self.qkv(x) # flops += N * self.dim * 3 * self.dim if temporal: flops += self.dim * N * T * T * 2 else: # attn = (q @ k.transpose(-2, -1)) flops += self.num_heads * N * (self.dim // self.num_heads) * N * T # x = (attn @ v) flops += self.num_heads * N * N * (self.dim // self.num_heads) * T # x = self.proj(x) # flops += N * self.dim * self.dim return flops

这段代码计算了一个窗口内的FLOPS(浮点操作数),其中N为令牌长度,T为时间步数。如果temporal为True,则计算的是temporal self-attention的FLOPS,否则计算的是普通的self-attention的FLOPS。具体来说,计算FLOPS的过程包括以下几个步骤: 1. 计算qkv,其中q、k、v均为大小为N×dim的矩阵,dim为模型的隐藏层维度。这一部分的FLOPS为N×dim×3×dim。 2. 如果是temporal self-attention,计算attn,其中attn为大小为N×T×T的矩阵,表示每个时间步之间的attention。这一部分的FLOPS为2×dim×N×T×T。 3. 如果是普通的self-attention,计算attn,其中attn为大小为num_heads×N×T×T的矩阵,表示每个头在每个时间步的attention。这一部分的FLOPS为num_heads×N×(dim/num_heads)×N×T。 4. 计算x,其中x为大小为num_heads×N×T×(dim/num_heads)的矩阵,表示每个头在每个时间步的输出。这一部分的FLOPS为num_heads×N×N×(dim/num_heads)×T。 5. 计算proj,其中proj为大小为N×dim的矩阵,表示self-attention的输出。这一部分的FLOPS为N×dim×dim。 最终,将所有步骤的FLOPS相加,即得到一个窗口内的总FLOPS。
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请你参考这个代码: class Linear_Attention(nn.Module): def __init__(self, embed_dim, num_heads=8, qkv_bias=False): super().__init__() self.embed_dim = embed_dim self.num_heads = num_heads head_dim = embed_dim // num_heads self.scale = head_dim ** -0.5 # 使用分组卷积替代全连接,减少参数量 self.qkv = nn.Conv2d(embed_dim, embed_dim * 3, kernel_size=1, bias=qkv_bias) self.proj = nn.Conv2d(embed_dim, embed_dim, kernel_size=1) self.norm = nn.GroupNorm(1, embed_dim) # 使用 GroupNorm 替代 LayerNorm def forward(self, x): B, C, H, W = x.shape # 使用卷积处理,避免reshape带来的内存开销 qkv = self.qkv(x).chunk(3, dim=1) q, k, v = map(lambda t: t.reshape(B, self.num_heads, -1, H*W), qkv) # [B, heads, C//heads, H*W] # 使用线性注意力机制(避免计算完整注意力矩阵) k = k.softmax(dim=-1) context = torch.matmul(k, v.transpose(-2, -1)) # [B, heads, C//heads, C//heads] attn_output = torch.matmul(context.transpose(-2, -1), q) # [B, heads, C//heads, H*W] attn_output = attn_output.reshape(B, C, H, W) x = x + self.proj(attn_output) x = self.norm(x) return x 修改一下下面的代码: class Linear_Attention(nn.Module): def __init__(self, embed_dim, num_heads=8): super().__init__() self.attention = nn.MultiheadAttention(embed_dim, num_heads) self.norm = nn.LayerNorm(embed_dim) def forward(self, x): B, C, H, W = x.shape x = x.reshape(B, C, H * W).permute(2, 0, 1) ## [H*W, B, C] attn_output, _ = self.attention(x, x, x) x = x + attn_output x = self.norm(x) x = x.permute(1, 2, 0).reshape(B, C, H, W) return x

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import time import math from functools import partial from typing import Optional, Callable import torch import torch.nn as nn import torch.nn.functional as F import torch.utils.checkpoint as checkpoint from einops import rearrange, repeat from timm.models.layers import DropPath, to_2tuple, trunc_normal_ try: from mamba_ssm.ops.selective_scan_interface import selective_scan_fn, selective_scan_ref except: pass # an alternative for mamba_ssm (in which causal_conv1d is needed) try: from selective_scan import selective_scan_fn as selective_scan_fn_v1 from selective_scan import selective_scan_ref as selective_scan_ref_v1 except: pass DropPath.__repr__ = lambda self: f"timm.DropPath({self.drop_prob})" def flops_selective_scan_ref(B=1, L=256, D=768, N=16, with_D=True, with_Z=False, with_Group=True, with_complex=False): """ u: r(B D L) delta: r(B D L) A: r(D N) B: r(B N L) C: r(B N L) D: r(D) z: r(B D L) delta_bias: r(D), fp32 ignores: [.float(), +, .softplus, .shape, new_zeros, repeat, stack, to(dtype), silu] """ import numpy as np # fvcore.nn.jit_handles def get_flops_einsum(input_shapes, equation): np_arrs = [np.zeros(s) for s in input_shapes] optim = np.einsum_path(equation, *np_arrs, optimize="optimal")[1] for line in optim.split("\n"): if "optimized flop" in line.lower(): # divided by 2 because we count MAC (multiply-add counted as one flop) flop = float(np.floor(float(line.split(":")[-1]) / 2)) return flop assert not with_complex flops = 0 # below code flops = 0 if False: ... """ dtype_in = u.dtype u = u.float() delta = delta.float() if delta_bias is not None: delta = delta + delta_bias[..., None].float() if delta_softplus: delta = F.softplus(delta) batch, dim, dstate = u.shape[0],

import torch import torch.nn as nn import torch.optim as optim from torch.optim.lr_scheduler import CosineAnnealingLR from torchvision import datasets, transforms from torch.utils.data import random_split, DataLoader import time import numpy as np import matplotlib.pyplot as plt from sklearn.metrics import confusion_matrix, classification_report import seaborn as sns import os import argparse from PIL import Image # 设置中文字体显示 plt.rcParams['font.sans-serif'] = ['SimHei', 'Microsoft YaHei', 'KaiTi'] plt.rcParams['axes.unicode_minus'] = False # 解决负号显示异常 # 设置随机种子,保证结果可复现 torch.manual_seed(42) np.random.seed(42) # 定义VGG网络 - 适配自定义数据集(VGG16简化版) class VGGCustom(nn.Module): def __init__(self, num_classes, input_size=(3, 224, 224)): super(VGGCustom, self).__init__() self.input_size = input_size # VGG核心:多个3x3卷积堆叠 + 最大池化 self.features = nn.Sequential( # 第一组:2个卷积层 + 池化 nn.Conv2d(3, 64, kernel_size=3, padding=1), nn.BatchNorm2d(64), nn.ReLU(inplace=True), nn.Conv2d(64, 64, kernel_size=3, padding=1), nn.BatchNorm2d(64), nn.ReLU(inplace=True), nn.MaxPool2d(kernel_size=2, stride=2), # 224x224 -> 112x112 # 第二组:2个卷积层 + 池化 nn.Conv2d(64, 128, kernel_size=3, padding=1), nn.BatchNorm2d(128), nn.ReLU(inplace=True), nn.Conv2d(128, 128, kernel_size=3, padding=1), nn.BatchNorm2d(128), nn.ReLU(inplace=True), nn.MaxPool2d(kernel_size=2, stride=2), # 112x112 -> 56x56 # 第三组:3个卷积层 + 池化 nn.Conv2d(128, 256, kernel_size=3, padding=1), nn.BatchNorm2d(256), nn.ReLU(inplace=True), nn.Conv2d(256, 256, kernel_size=3, padding=1), nn.BatchNorm2d(256), nn.ReLU(inplace=True), nn.Conv2d(256, 256, kernel_size=3, padding=1), nn.BatchNorm2d(256), nn.ReLU(inplace=True), nn.MaxPool2d(kernel_size=2, stride=2), # 56x56 -> 28x28 # 第四组:3个卷积层 + 池化 nn.Conv2d(256, 512, kernel_size=3, padding=1), nn.BatchNorm2d(512), nn.ReLU(inplace=True), nn.Conv2d(512, 512, kernel_size=3, padding=1), nn.BatchNorm2d(512), nn.ReLU(inplace=True), nn.Conv2d(512, 512, kernel_size=3, padding=1), nn.BatchNorm2d(512), nn.ReLU(inplace=True), nn.MaxPool2d(kernel_size=2, stride=2), # 28x28 -> 14x14 # 第五组:3个卷积层 + 池化 nn.Conv2d(512, 512, kernel_size=3, padding=1), nn.BatchNorm2d(512), nn.ReLU(inplace=True), nn.Conv2d(512, 512, kernel_size=3, padding=1), nn.BatchNorm2d(512), nn.ReLU(inplace=True), nn.Conv2d(512, 512, kernel_size=3, padding=1), nn.BatchNorm2d(512), nn.ReLU(inplace=True), nn.MaxPool2d(kernel_size=2, stride=2), # 14x14 -> 7x7 nn.Dropout2d(p=0.4) ) # 计算全连接层输入维度 with torch.no_grad(): dummy_input = torch.zeros(1, *input_size) features_output = self.features(dummy_input) fc_input_dim = features_output.view(1, -1).size(1) # 分类层 self.classifier = nn.Sequential( nn.Linear(fc_input_dim, 4096), nn.BatchNorm1d(4096), nn.ReLU(inplace=True), nn.Dropout(p=0.5), nn.Linear(4096, 4096), nn.BatchNorm1d(4096), nn.ReLU(inplace=True), nn.Dropout(p=0.5), nn.Linear(4096, num_classes) ) def forward(self, x): x = self.features(x) x = torch.flatten(x, 1) x = self.classifier(x) return x # 创建不同配置的VGG变体模型 def vgg_custom_basic(num_classes, input_size=(3, 224, 224)): """基础版VGG(类似VGG16),适合自定义数据集""" return VGGCustom(num_classes=num_classes, input_size=input_size) def vgg_custom_lite(num_classes, input_size=(3, 224, 224)): """轻量版VGG(减少卷积通道数),适合小数据集或显存有限的情况""" model = VGGCustom(num_classes=num_classes, input_size=input_size) # 减少卷积层通道数,降低参数量 model.features = nn.Sequential( # 第一组 nn.Conv2d(3, 32, kernel_size=3, padding=1), nn.BatchNorm2d(32), nn.ReLU(inplace=True), nn.Conv2d(32, 32, kernel_size=3, padding=1), nn.BatchNorm2d(32), nn.ReLU(inplace=True), nn.MaxPool2d(kernel_size=2, stride=2), # 第二组 nn.Conv2d(32, 64, kernel_size=3, padding=1), nn.BatchNorm2d(64), nn.ReLU(inplace=True), nn.Conv2d(64, 64, kernel_size=3, padding=1), nn.BatchNorm2d(64), nn.ReLU(inplace=True), nn.MaxPool2d(kernel_size=2, stride=2), # 第三组 nn.Conv2d(64, 128, kernel_size=3, padding=1), nn.BatchNorm2d(128), nn.ReLU(inplace=True), nn.Conv2d(128, 128, kernel_size=3, padding=1), nn.BatchNorm2d(128), nn.ReLU(inplace=True), nn.Conv2d(128, 128, kernel_size=3, padding=1), nn.BatchNorm2d(128), nn.ReLU(inplace=True), nn.MaxPool2d(kernel_size=2, stride=2), # 第四组 nn.Conv2d(128, 256, kernel_size=3, padding=1), nn.BatchNorm2d(256), nn.ReLU(inplace=True), nn.Conv2d(256, 256, kernel_size=3, padding=1), nn.BatchNorm2d(256), nn.ReLU(inplace=True), nn.Conv2d(256, 256, kernel_size=3, padding=1), nn.BatchNorm2d(256), nn.ReLU(inplace=True), nn.MaxPool2d(kernel_size=2, stride=2), # 第五组 nn.Conv2d(256, 256, kernel_size=3, padding=1), nn.BatchNorm2d(256), nn.ReLU(inplace=True), nn.Conv2d(256, 256, kernel_size=3, padding=1), nn.BatchNorm2d(256), nn.ReLU(inplace=True), nn.Conv2d(256, 256, kernel_size=3, padding=1), nn.BatchNorm2d(256), nn.ReLU(inplace=True), nn.MaxPool2d(kernel_size=2, stride=2), nn.Dropout2d(p=0.4) ) # 重新计算全连接层输入维度 with torch.no_grad(): dummy_input = torch.zeros(1, *input_size) features_output = model.features(dummy_input) fc_input_dim = features_output.view(1, -1).size(1) # 调整分类层 model.classifier = nn.Sequential( nn.Linear(fc_input_dim, 2048), # 减少全连接层维度 nn.BatchNorm1d(2048), nn.ReLU(inplace=True), nn.Dropout(p=0.5), nn.Linear(2048, 1024), nn.BatchNorm1d(1024), nn.ReLU(inplace=True), nn.Dropout(p=0.5), nn.Linear(1024, num_classes) ) return model # 数据加载与预处理 - 适配自定义数据集 def load_data(data_path, input_size=(224, 224), train_ratio=0.7, val_ratio=0.2): mean = (0.485, 0.456, 0.406) # ImageNet均值 std = (0.229, 0.224, 0.225) # ImageNet标准差 train_transform = transforms.Compose([ transforms.Resize(input_size), transforms.RandomCrop(input_size, padding=16), transforms.RandomHorizontalFlip(p=0.5), transforms.RandomRotation(15), transforms.ColorJitter(brightness=0.2, contrast=0.2, saturation=0.2, hue=0.1), transforms.ToTensor(), transforms.Normalize(mean, std), transforms.RandomErasing(p=0.3, scale=(0.02, 0.25)), ]) val_test_transform = transforms.Compose([ transforms.Resize(input_size), transforms.ToTensor(), transforms.Normalize(mean, std), ]) full_dataset = datasets.ImageFolder(root=data_path, transform=train_transform) class_names = full_dataset.classes num_classes = len(class_names) print(f"已加载自定义数据集,共 {num_classes} 个类别: {class_names}") # 划分数据集 total_size = len(full_dataset) train_size = int(train_ratio * total_size) val_size = int(val_ratio * total_size) test_size = total_size - train_size - val_size train_dataset, val_dataset, test_dataset = random_split( full_dataset, [train_size, val_size, test_size], generator=torch.Generator().manual_seed(42) ) # 替换验证集和测试集的transform val_dataset.dataset.transform = val_test_transform test_dataset.dataset.transform = val_test_transform # 创建数据加载器(VGG参数量较大,可适当减小batch_size) train_loader = DataLoader( train_dataset, batch_size=16, shuffle=True, num_workers=2, pin_memory=True ) val_loader = DataLoader( val_dataset, batch_size=16, shuffle=False, num_workers=2, pin_memory=True ) test_loader = DataLoader( test_dataset, batch_size=16, shuffle=False, num_workers=2, pin_memory=True ) return train_loader, val_loader, test_loader, class_names, num_classes, mean, std # 训练模型(保持原有流程,适配VGG) def train_model(model, train_loader, val_loader, criterion, optimizer, scheduler, device, epochs=100, start_epoch=0, best_val_acc=0.0): model.train() train_losses, train_accs, val_losses, val_accs = [], [], [], [] if start_epoch > 0: try: history = torch.load(f'models/training_history_{type(model).__name__}_custom.pth') train_losses, train_accs, val_losses, val_accs = history['train_losses'], history['train_accs'], history[ 'val_losses'], history['val_accs'] print(f"已加载训练历史,从第 {start_epoch+1} 轮开始训练") except: print("无法加载训练历史,将重新记录") train_losses = [0] * start_epoch train_accs = [0] * start_epoch val_losses = [0] * start_epoch val_accs = [0] * start_epoch for epoch in range(start_epoch, epochs): running_loss, correct, total = 0.0, 0, 0 start_time = time.time() model.train() for inputs, targets in train_loader: inputs, targets = inputs.to(device), targets.to(device) optimizer.zero_grad() outputs = model(inputs) loss = criterion(outputs, targets) loss.backward() optimizer.step() running_loss += loss.item() _, predicted = outputs.max(1) total += targets.size(0) correct += predicted.eq(targets).sum().item() epoch_train_loss = running_loss / len(train_loader) epoch_train_acc = 100.0 * correct / total train_losses.append(epoch_train_loss) train_accs.append(epoch_train_acc) val_loss, val_acc = evaluate_on_val(model, val_loader, criterion, device) val_losses.append(val_loss) val_accs.append(val_acc) scheduler.step() end_time = time.time() if val_acc > best_val_acc: best_val_acc = val_acc torch.save(model, f'models/best_{type(model).__name__}_custom.pth') print(f"已保存最佳模型,验证准确率: {val_acc:.2f}%") save_checkpoint({ 'epoch': epoch + 1, 'model_state_dict': model.state_dict(), 'optimizer_state_dict': optimizer.state_dict(), 'scheduler_state_dict': scheduler.state_dict(), 'best_val_acc': best_val_acc, }, f'models/checkpoint_{type(model).__name__}_custom.pth') torch.save({ 'train_losses': train_losses, 'train_accs': train_accs, 'val_losses': val_losses, 'val_accs': val_accs, }, f'models/training_history_{type(model).__name__}_custom.pth') print( f'Epoch {epoch + 1}/{epochs}, ' f'Train Loss: {epoch_train_loss:.4f}, Train Acc: {epoch_train_acc:.2f}%, ' f'Val Loss: {val_loss:.4f}, Val Acc: {val_acc:.2f}%, ' f'Time: {end_time - start_time:.2f}s' ) return train_losses, train_accs, val_losses, val_accs # 验证集评估 def evaluate_on_val(model, val_loader, criterion, device): model.eval() val_loss, correct, total = 0, 0, 0 with torch.no_grad(): for inputs, targets in val_loader: inputs, targets = inputs.to(device), targets.to(device) outputs = model(inputs) loss = criterion(outputs, targets) val_loss += loss.item() _, predicted = outputs.max(1) total += targets.size(0) correct += predicted.eq(targets).sum().item() return val_loss / len(val_loader), 100.0 * correct / total # 测试集评估(增强可视化功能) def evaluate_model(model, test_loader, device, class_names, mean, std): model.eval() test_loss = 0 correct = 0 total = 0 all_targets = [] all_predicted = [] all_inputs = [] # 保存图像用于定性可视化 criterion = nn.CrossEntropyLoss() with torch.no_grad(): for inputs, targets in test_loader: all_inputs.append(inputs) # 收集输入图像 inputs, targets = inputs.to(device), targets.to(device) outputs = model(inputs) loss = criterion(outputs, targets) test_loss += loss.item() _, predicted = outputs.max(1) total += targets.size(0) correct += predicted.eq(targets).sum().item() all_targets.extend(targets.cpu().numpy()) all_predicted.extend(predicted.cpu().numpy()) test_loss /= len(test_loader) test_acc = 100.0 * correct / total print(f'Test Loss: {test_loss:.4f}, Test Acc: {test_acc:.2f}%') # 计算混淆矩阵和分类报告 cm = confusion_matrix(all_targets, all_predicted) report = classification_report( all_targets, all_predicted, target_names=class_names, labels=list(range(len(class_names))), output_dict=True ) print("分类报告:") print(classification_report( all_targets, all_predicted, target_names=class_names, labels=list(range(len(class_names))) )) # 定量可视化:性能指标图表 plot_quantitative_metrics(report, class_names, model) # 定性可视化:预测案例展示 all_inputs = torch.cat(all_inputs, dim=0) visualize_predictions(all_inputs, all_targets, all_predicted, class_names, mean, std, model) return test_loss, test_acc, cm, class_names # 定量可视化:各类别性能指标对比 def plot_quantitative_metrics(report, class_names, model): metrics = ['precision', 'recall', 'f1-score'] data = {m: [report[cls][m] for cls in class_names] for m in metrics} # 绘制类别性能对比图 x = np.arange(len(class_names)) width = 0.25 fig, ax = plt.subplots(figsize=(14, 6)) rects1 = ax.bar(x - width, data['precision'], width, label='精确率') rects2 = ax.bar(x, data['recall'], width, label='召回率') rects3 = ax.bar(x + width, data['f1-score'], width, label='F1分数') ax.set_xlabel('类别') ax.set_ylabel('分数') ax.set_title(f'{type(model).__name__} 各类别性能指标') ax.set_xticks(x) ax.set_xticklabels(class_names, rotation=45) ax.legend() # 在柱状图上标注数值 def autolabel(rects): for rect in rects: height = rect.get_height() ax.annotate(f'{height:.2f}', xy=(rect.get_x() + rect.get_width() / 2, height), xytext=(0, 3), textcoords="offset points", ha='center', va='bottom') autolabel(rects1) autolabel(rects2) autolabel(rects3) plt.tight_layout() plt.savefig(f'class_metrics_{type(model).__name__}_custom.png') plt.show() # 绘制总体性能指标 overall = report['weighted avg'] fig, ax = plt.subplots(figsize=(8, 5)) ax.bar(metrics, [overall[m] for m in metrics], color=['#4CAF50', '#2196F3', '#FFC107']) ax.set_ylim(0, 1.0) ax.set_title(f'{type(model).__name__} 总体性能指标') for i, v in enumerate([overall[m] for m in metrics]): ax.text(i, v + 0.02, f'{v:.2f}', ha='center') plt.savefig(f'overall_metrics_{type(model).__name__}_custom.png') plt.show() # 定性可视化:展示正确和错误预测的案例 def visualize_predictions(images, targets, predictions, class_names, mean, std, model): def denormalize(tensor): tensor = tensor.clone() for t, m, s in zip(tensor, mean, std): t.mul_(s).add_(m) return tensor.clamp(0, 1) # 筛选正确和错误的预测索引 correct_indices = [i for i in range(len(targets)) if targets[i] == predictions[i]] incorrect_indices = [i for i in range(len(targets)) if targets[i] != predictions[i]] # 各选10个样本 num_samples = 10 correct_samples = correct_indices[:num_samples] incorrect_samples = incorrect_indices[:num_samples] # 展示正确预测的案例 if correct_samples: fig, axes = plt.subplots(2, 5, figsize=(15, 6)) fig.suptitle(f'{type(model).__name__} - 正确预测案例', fontsize=16) axes = axes.flatten() for i, idx in enumerate(correct_samples): ax = axes[i] img = denormalize(images[idx]).permute(1, 2, 0).numpy() ax.imshow(img) ax.set_title(f"真实: {class_names[targets[idx]]}\n预测: {class_names[predictions[idx]]}") ax.axis('off') plt.tight_layout(rect=[0, 0, 1, 0.95]) plt.savefig(f'correct_predictions_{type(model).__name__}_custom.png') plt.show() # 展示错误预测的案例 if incorrect_samples: fig, axes = plt.subplots(2, 5, figsize=(15, 6)) fig.suptitle(f'{type(model).__name__} - 错误预测案例', fontsize=16) axes = axes.flatten() for i, idx in enumerate(incorrect_samples): ax = axes[i] img = denormalize(images[idx]).permute(1, 2, 0).numpy() ax.imshow(img) ax.set_title(f"真实: {class_names[targets[idx]]}\n预测: {class_names[predictions[idx]]}") ax.axis('off') plt.tight_layout(rect=[0, 0, 1, 0.95]) plt.savefig(f'incorrect_predictions_{type(model).__name__}_custom.png') plt.show() # 保存/加载检查点 def save_checkpoint(state, filename): torch.save(state, filename) def load_checkpoint(model, optimizer, scheduler, filename): try: checkpoint = torch.load(filename) model.load_state_dict(checkpoint['model_state_dict']) optimizer.load_state_dict(checkpoint['optimizer_state_dict']) scheduler.load_state_dict(checkpoint['scheduler_state_dict']) return model, optimizer, scheduler, checkpoint['epoch'], checkpoint['best_val_acc'] except: print("无法加载检查点,将从头开始训练") return model, optimizer, scheduler, 0, 0.0 # 模型统计信息 def count_parameters(model): return sum(p.numel() for p in model.parameters() if p.requires_grad) def count_flops(model, input_size=(3, 224, 224)): device = next(model.parameters()).device model.eval() x = torch.rand(1, *input_size).to(device) try: from thop import profile flops, _ = profile(model, inputs=(x,)) return flops / 1e9 # VGG参数量大,用G为单位 except ImportError: print("请安装thop库计算FLOPs: pip install thop") return None # 主函数 def main(): parser = argparse.ArgumentParser(description='VGG用于自定义数据集图像识别') parser.add_argument('--data_path', type=str, required=True, help='自定义数据集根目录路径') parser.add_argument('--model', type=str, default='vgg_custom_basic', choices=['vgg_custom_basic', 'vgg_custom_lite']) # 新增VGG模型选项 parser.add_argument('--epochs', type=int, default=100) parser.add_argument('--lr', type=float, default=0.0005) # VGG学习率可适当减小 parser.add_argument('--input_size', type=int, nargs=2, default=[224, 224], help='输入图像尺寸 (width height)') parser.add_argument('--resume', action='store_true') args = parser.parse_args() device = torch.device("cuda" if torch.cuda.is_available() else "cpu") print(f"使用设备: {device}") os.makedirs('models', exist_ok=True) # 加载数据 train_loader, val_loader, test_loader, class_names, num_classes, mean, std = load_data( data_path=args.data_path, input_size=tuple(args.input_size), train_ratio=0.7, val_ratio=0.2 ) print( f"数据划分: 训练集 {len(train_loader.dataset)} 样本, 验证集 {len(val_loader.dataset)} 样本, 测试集 {len(test_loader.dataset)} 样本") # 创建VGG模型 input_size = (3, args.input_size[0], args.input_size[1]) model_dict = { 'vgg_custom_basic': vgg_custom_basic, 'vgg_custom_lite': vgg_custom_lite, } model = model_dict[args.model](num_classes=num_classes, input_size=input_size).to(device) print(f"使用模型: {args.model},输入尺寸: {input_size}") # 定义训练组件(VGG适合用SGD+动量) criterion = nn.CrossEntropyLoss(label_smoothing=0.1) optimizer = optim.SGD(model.parameters(), lr=args.lr, momentum=0.9, weight_decay=5e-4) # VGG常用SGD优化器 scheduler = CosineAnnealingLR(optimizer, T_max=args.epochs, eta_min=1e-6) # 模型统计信息(VGG参数量远大于AlexNet) params = count_parameters(model) flops = count_flops(model, input_size=input_size) print(f"模型参数量: {params / 1e6:.2f} M") print(f"模型FLOPs: {flops:.2f} G" if flops else "未计算FLOPs") # 从检查点续训 start_epoch, best_val_acc = 0, 0.0 if args.resume: model, optimizer, scheduler, start_epoch, best_val_acc = load_checkpoint( model, optimizer, scheduler, f'models/checkpoint_{type(model).__name__}_custom.pth' ) # 训练模型 print("开始训练模型...") train_losses, train_accs, val_losses, val_accs = train_model( model, train_loader, val_loader, criterion, optimizer, scheduler, device, args.epochs, start_epoch, best_val_acc ) # 评估模型 best_model = torch.load(f'models/best_{type(model).__name__}_custom.pth') best_model.to(device) print("开始评估模型...") test_loss, test_acc, cm, class_names = evaluate_model(best_model, test_loader, device, class_names, mean, std) # 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