def image_batch(request):
    """
    Create image fixture of shape NFHWC and NCFHW.
    """
    channels_first = request.param
    test_input = np.ones((2, 3, 32, 32))
    if not channels_first:
        test_input = np.transpose(test_input, (0, 2, 3, 1))
    test_mean = [0] * 3
    test_std = [1] * 3
    test_output = test_input.copy()
    return test_input, test_output, test_mean, test_std

    Create image fixture of shape NFHWC and NCFHW.
    
tests/preprocessing/test_standardisation_mean_std.py