ViT-CIFAR10/Classification-noisy/scripts/get_raw_data.py

#读取数据集，在../dataset/raw_data下按照数据集的完整排序,1.png,2.png,3.png,...保存

import os
import yaml
import numpy as np
import torch
import torchvision
import torchvision.transforms as transforms
from PIL import Image
from tqdm import tqdm
import sys

def unpickle(file):
    """读取CIFAR-10数据文件"""
    import pickle
    with open(file, 'rb') as fo:
        dict = pickle.load(fo, encoding='bytes')
    return dict
    
def add_noise_for_preview(image, noise_type, level):
    """向图像添加不同类型的噪声的预览
    
    Args:
        image: 输入图像 (Tensor: C x H x W)，范围[0,1]
        noise_type: 噪声类型 (int, 1-3)
        level: 噪声强度 (float)
        
    Returns:
        noisy_image: 添加噪声后的图像 (Tensor: C x H x W)
    """
    # 将图像从Tensor转为Numpy数组
    img_np = image.cpu().numpy()
    img_np = np.transpose(img_np, (1, 2, 0))  # C x H x W -> H x W x C
    
    # 根据噪声类型添加噪声
    if noise_type == 1:  # 高斯噪声
        noise = np.random.normal(0, level, img_np.shape)
        noisy_img = img_np + noise
        noisy_img = np.clip(noisy_img, 0, 1)
    
    elif noise_type == 2:  # 椒盐噪声
        # 创建掩码，确定哪些像素将变为椒盐噪声
        noisy_img = img_np.copy()  # 创建副本而不是直接修改原图
        mask = np.random.random(img_np.shape[:2])
        # 椒噪声 (黑点)
        noisy_img[mask < level/2] = 0
        # 盐噪声 (白点)
        noisy_img[mask > 1 - level/2] = 1
    
    elif noise_type == 3:  # 泊松噪声
        # 确保输入值为正数
        lam = np.maximum(img_np * 10.0, 0.0001)  # 避免负值和零值
        noisy_img = np.random.poisson(lam) / 10.0
        noisy_img = np.clip(noisy_img, 0, 1)
    
    else:  # 默认返回原图像
        noisy_img = img_np
    
    # 将噪声图像从Numpy数组转回Tensor
    noisy_img = np.transpose(noisy_img, (2, 0, 1))  # H x W x C -> C x H x W
    noisy_tensor = torch.from_numpy(noisy_img.astype(np.float32))
    return noisy_tensor

def save_images_from_cifar10_with_noisy(dataset_path, save_dir):
    """从CIFAR-10数据集中保存图像，对指定索引添加噪声
    
    Args:
        dataset_path: CIFAR-10数据集路径
        save_dir: 图像保存路径
    """
    # 创建保存目录
    os.makedirs(save_dir, exist_ok=True)
    
    # 读取噪声样本的索引
    noise_index_path = os.path.join(os.path.dirname(os.path.dirname(os.path.abspath(__file__))), 'dataset', 'noise_index.npy')
    if os.path.exists(noise_index_path):
        noise_indices = np.load(noise_index_path)
        print(f"已加载 {len(noise_indices)} 个噪声样本索引")
    else:
        noise_indices = []
        print("未找到噪声索引文件，将不添加噪声")
    
    # 加载配置
    config_path = './train.yaml'
    with open(config_path, 'r') as f:
        config = yaml.safe_load(f)
    
    # 读取噪声参数
    noise_levels = config.get('noise_levels', {})
    gaussian_level = noise_levels.get('gaussian', [0.3])
    salt_pepper_level = noise_levels.get('salt_pepper', [0.1])
    poisson_level = noise_levels.get('poisson', [1.0])[0]
    
    # 获取训练集数据
    train_data = []
    train_labels = []
    
    # 读取训练数据
    for i in range(1, 6):
        batch_file = os.path.join(dataset_path, f'data_batch_{i}')
        if os.path.exists(batch_file):
            print(f"读取训练批次 {i}")
            batch = unpickle(batch_file)
            train_data.append(batch[b'data'])
            train_labels.extend(batch[b'labels'])
    
    # 合并所有训练数据
    if train_data:
        train_data = np.vstack(train_data)
        train_data = train_data.reshape(-1, 3, 32, 32).transpose(0, 2, 3, 1)
    
    # 读取测试数据
    test_file = os.path.join(dataset_path, 'test_batch')
    if os.path.exists(test_file):
        print("读取测试数据")
        test_batch = unpickle(test_file)
        test_data = test_batch[b'data']
        test_labels = test_batch[b'labels']
        test_data = test_data.reshape(-1, 3, 32, 32).transpose(0, 2, 3, 1)
    else:
        test_data = []
        test_labels = []
    
    # 合并训练和测试数据
    all_data = np.concatenate([train_data, test_data]) if len(test_data) > 0 and len(train_data) > 0 else (train_data if len(train_data) > 0 else test_data)
    all_labels = train_labels + test_labels if len(test_labels) > 0 and len(train_labels) > 0 else (train_labels if len(train_labels) > 0 else test_labels)
    
    # 设置设备
    device = torch.device('cuda' if torch.cuda.is_available() else 'cpu')
    
    # 保存图像
    print(f"保存 {len(all_data)} 张图像...")
    
    for i, (img, label) in enumerate(tqdm(zip(all_data, all_labels), total=len(all_data))):
        # 检查索引是否在噪声样本索引中
        if i in noise_indices:
            # 为该样本确定噪声类型和强度
            noise_type = None
            level = None
            
            if label == 2:  # 高斯噪声强
                noise_type = 1
                level = gaussian_level[1]
            elif label == 3:  # 高斯噪声弱
                noise_type = 1
                level = gaussian_level[0]
            elif label == 4:  # 椒盐噪声强
                noise_type = 2
                level = salt_pepper_level[1]
            elif label == 5:  # 椒盐噪声弱
                noise_type = 2
                level = salt_pepper_level[0]
            elif label == 6:  # 泊松噪声
                noise_type = 3
                level = poisson_level
            elif label == 7:  # 泊松噪声
                noise_type = 3
                level = poisson_level
            
            # 如果是需要添加噪声的标签，则添加噪声
            if noise_type is not None and level is not None:
                # 转换为tensor
                img_tensor = torch.from_numpy(img.astype(np.float32) / 255.0).permute(2, 0, 1).to(device)
                # 添加噪声
                noisy_tensor = add_noise_for_preview(img_tensor, noise_type, level)
                # 转回numpy并保存
                noisy_img = (noisy_tensor.permute(1, 2, 0).cpu().numpy() * 255).astype(np.uint8)
                noisy_pil = Image.fromarray(noisy_img)
                noisy_pil.save(os.path.join(save_dir, f"{i}.png"))
            else:
                # 普通保存
                img_pil = Image.fromarray(img)
                img_pil.save(os.path.join(save_dir, f"{i}.png"))
        else:
            # 保存原始图像
            img_pil = Image.fromarray(img)
            img_pil.save(os.path.join(save_dir, f"{i}.png"))
    
    print(f"完成! {len(all_data)} 张图像已保存到 {save_dir}, 其中 {len(noise_indices)} 张添加了噪声")

if __name__ == "__main__":
    # 设置路径
    dataset_path = "../dataset/cifar-10-batches-py"
    save_dir = "../dataset/raw_data"
    
    # 检查数据集是否存在，如果不存在则下载
    if not os.path.exists(dataset_path):
        print("数据集不存在，正在下载...")
        os.makedirs("../dataset", exist_ok=True)
        transform = transforms.Compose([transforms.ToTensor()])
        trainset = torchvision.datasets.CIFAR10(root="../dataset", train=True, download=True, transform=transform)
    
    # 保存图像
    save_images_from_cifar10_with_noisy(dataset_path, save_dir)