dataloaders.py

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


def get_mnist_dataloaders(batch_size=128):
    """MNIST dataloader with (32, 32) sized images."""
    # Resize images so they are a power of 2
    all_transforms = transforms.Compose([
        transforms.Resize(32),
        transforms.ToTensor()
    ])
    # Get train and test data
    train_data = datasets.MNIST('../data', train=True, download=True,
                                transform=all_transforms)
    test_data = datasets.MNIST('../data', train=False,
                               transform=all_transforms)
    # Create dataloaders
    train_loader = DataLoader(train_data, batch_size=batch_size, shuffle=True)
    test_loader = DataLoader(test_data, batch_size=batch_size, shuffle=True)
    return train_loader, test_loader


def get_fashion_mnist_dataloaders(batch_size=128):
    """Fashion MNIST dataloader with (32, 32) sized images."""
    # Resize images so they are a power of 2
    all_transforms = transforms.Compose([
        transforms.Resize(32),
        transforms.ToTensor()
    ])
    # Get train and test data
    train_data = datasets.FashionMNIST('../fashion_data', train=True, download=True,
                                       transform=all_transforms)
    test_data = datasets.FashionMNIST('../fashion_data', train=False,
                                      transform=all_transforms)
    # Create dataloaders
    train_loader = DataLoader(train_data, batch_size=batch_size, shuffle=True)
    test_loader = DataLoader(test_data, batch_size=batch_size, shuffle=True)
    return train_loader, test_loader


def get_lsun_dataloader(path_to_data='../lsun', dataset='bedroom_train',
                        batch_size=64):
    """LSUN dataloader with (128, 128) sized images.

    path_to_data : str
        One of 'bedroom_val' or 'bedroom_train'
    """
    # Compose transforms
    transform = transforms.Compose([
        transforms.Resize(128),
        transforms.CenterCrop(128),
        transforms.ToTensor()
    ])

    # Get dataset
    lsun_dset = datasets.LSUN(db_path=path_to_data, classes=[dataset],
                              transform=transform)

    # Create dataloader
    return DataLoader(lsun_dset, batch_size=batch_size, shuffle=True)