Normalization for images and other input data

Here is my custom DATASET

In each sample, I have the image data and other data (float number)
I hope I can do the normalization for image, tr_angles and pls.

Thanks a lot.

class PLDataset(Dataset):
    """Face Landmarks dataset."""

    def __init__(self, csv_file, root_dir, transform=None):
            csv_file (string): Path to the csv file with annotations.
            root_dir (string): Directory with all the images.
            transform (callable, optional): Optional transform to be applied
                on a sample.
        self.landmarks_frame = pd.read_excel(csv_file)
        self.root_dir = root_dir
        self.transform = transform

    def __len__(self):
        return len(self.landmarks_frame)

    def __getitem__(self, idx):
        if torch.is_tensor(idx):
            idx = idx.tolist()

        img_names = os.path.join(self.root_dir,
                                 self.landmarks_frame.iloc[idx, 0])
        image = io.imread(img_names)

        pls = self.landmarks_frame.iloc[idx, 5:9]  # not [:, 5:9]
        tr_angles = self.landmarks_frame.iloc[idx, 9:14]
        positions = self.landmarks_frame.iloc[idx, 3:5]

        image = image.astype('float')  # .values
        pls = pls.values.astype('float')
        tr_angles = tr_angles.values.astype('float')
        positions = positions.values.astype('float')

        sample = {'image': image,
                  'pls': pls,
                  'tr_angles': tr_angles,
                  'positions': positions}

        if self.transform:
            sample = self.transform(sample)

        return sample

Now I just have my own ToTensor() function,

class ToTensor(object):
    """Convert ndarrays in sample to Tensors."""

    def __call__(self, sample):
        image, pls, tr_angles, positions = \
            sample['image'], sample['pls'], sample['tr_angles'], sample['positions']
        image = image[np.newaxis, :, :]
        # swap color axis because
        # numpy image: H x W x C
        # torch image: C X H X W
        # image = image.transpose((2, 0, 1)) # single channel
        return {'image': torch.from_numpy(image),
                'pls': torch.from_numpy(pls),
                'tr_angles': torch.from_numpy(tr_angles),
                'positions': torch.from_numpy(positions)