import re


def extract_jxl_ds(stderr: bytes) -> float:
    """ Extract decompression speed from the djxl output

    :param stderr: Console output
    :return: Decompression speed, in MP/s
    """

    ds: str = re.findall(r"\d+.\d+ MP/s", str(stderr, "utf-8"))[0]

    return float(ds[:-5])