color_conversions.py 文件源码

def Lab_to_LCHab(cobj, *args, **kwargs):
    """
    Convert from CIE Lab to LCH(ab).
    """

    lch_l = cobj.lab_l
    lch_c = math.sqrt(math.pow(float(cobj.lab_a), 2) + math.pow(float(cobj.lab_b), 2))
    lch_h = math.atan2(float(cobj.lab_b), float(cobj.lab_a))

    if lch_h > 0:
        lch_h = (lch_h / math.pi) * 180
    else:
        lch_h = 360 - (math.fabs(lch_h) / math.pi) * 180

    return LCHabColor(
        lch_l, lch_c, lch_h, observer=cobj.observer, illuminant=cobj.illuminant)


# noinspection PyPep8Naming,PyUnusedLocal