Decode HxZip data stream
    
    :param int data_size: the number of items when ``data`` is uncompressed
    :param str data: a raw stream of data to be unpacked
    :return numpy.array output: an array of ``numpy.uint8``

def hxzip_decode(data_size, data):
    """Decode HxZip data stream
    
    :param int data_size: the number of items when ``data`` is uncompressed
    :param str data: a raw stream of data to be unpacked
    :return numpy.array output: an array of ``numpy.uint8``
    """
    import zlib
    data_stream = zlib.decompress(data)
    output = numpy.array(struct.unpack('<{}B'.format(len(data_stream)), data_stream), dtype=numpy.uint8)
    assert len(output) == data_size
    return output