utils/data_loader.py

from torchvision import datasets, transforms
from torch.utils.data import DataLoader

def get_data_loaders(data_dir, batch_size=32):
    # Data augmentation + normalization for training
    transform_train = transforms.Compose([
        transforms.RandomResizedCrop(128),
        transforms.RandomHorizontalFlip(),
        transforms.RandomRotation(10),
        transforms.ColorJitter(brightness=0.2, contrast=0.2, saturation=0.2),
        transforms.ToTensor(),
        transforms.Normalize([0.5, 0.5, 0.5], [0.5, 0.5, 0.5])
    ])

    # Only resize + normalize for validation
    transform_val = transforms.Compose([
        transforms.Resize((128, 128)),
        transforms.ToTensor(),
        transforms.Normalize([0.5, 0.5, 0.5], [0.5, 0.5, 0.5])
    ])

    train_dir = f"{data_dir}/training"
    val_dir = f"{data_dir}/validation"

    train_dataset = datasets.ImageFolder(train_dir, transform=transform_train)
    val_dataset = datasets.ImageFolder(val_dir, transform=transform_val)

    train_loader = DataLoader(train_dataset, batch_size=batch_size, shuffle=True)
    val_loader = DataLoader(val_dataset, batch_size=batch_size, shuffle=False)

    return train_loader, val_loader, train_dataset.classes