colorimetry.py 文件源码

def spectrum_to_XYZ_emissive(spectrum_dict, cmf='1931_2deg'):
    ''' Converts a reflective or transmissive spectrum to XYZ coordinates.

    Args:
        spectrum_dict (`dict`): dictionary with wvl, values keys.  Wvl in units of nm.

        cmf (`str`): which color matching function to use, defaults to
            CIE 1931 2 degree observer.

    Returns:
        `tuple` containing:

            `float`: X

            `float`: Y

            `float`: Z

    '''
    wvl, values = spectrum_dict['wvl'], spectrum_dict['values']

    cmf = get_cmf(cmf)
    wvl_cmf = cmf['wvl']
    try:
        can_be_direct = np.allclose(wvl_cmf, wvl)
    except ValueError as e:
        can_be_direct = False
    if not can_be_direct:
        dat_interpf = interp1d(wvl, values, kind='linear', bounds_error=False, fill_value=0, assume_sorted=True)
        values = dat_interpf(wvl_cmf)

    dw = wvl_cmf[1] - wvl_cmf[0]
    k = 100 / (values * cmf['Y']).sum(axis=0) / dw
    X = k * (values * cmf['X']).sum(axis=0)
    Y = k * (values * cmf['Y']).sum(axis=0)
    Z = k * (values * cmf['Z']).sum(axis=0)
    return X, Y, Z