def validate_image_choices(dep_var, x_dim, bs, splits, num_epochs, num_channels):
    """
    Checks to see if user choices are consistent with expectations
    Returns failure message if it fails, None otherwise.
    """
    splits = [float(num) for num in splits]

    if sum(splits) != 1:
        return 'Splits must add up to 1 (Currently adding up to ' + str(sum(splits)) + ')'
    if num_channels not in [1, 3]:
        return 'Number of channels in image (' + str(num_channels) + ' found) should be 1 or 3'
    return None