def _slice_ndfilter(data, filter_func, slices, args, size, footprint, kwargs):
    """
    Helper function passing image slices to `scipy.ndimage` filters that is
    pickleable for threading with `multiprocessing`
    
    Parameters
    ----------
    data, filter_func, args, size, footprint : 
        See `multiprocessing_ndfilter`
    
    slices : (slice, slice, slice, slice)
        Array slices for insert a cutout back into a larger parent array
        
    Returns
    -------
    filtered : array-like
        Filtered data
    
    slices : tuple
        `slices` as input
        
    """
    filtered = filter_func(data, *args, 
                           size=size, footprint=footprint,
                           **kwargs)
                           
    return filtered, slices