def lch2lab(lch):
 lch = _prepare_lab_array(lch)
 (c, h) = (lch[..., 1], lch[..., 2])
 (lch[..., 1], lch[..., 2]) = ((c * np.cos(h)), (c * np.sin(h)))
 return lch

def lch2lab ( lch ) : lch = _prepare_lab_array ( lch ) ( c , h ) = ( lch [ ... , 1 ] , lch [ ... , 2 ] ) ( lch [ ... , 1 ] , lch [ ... , 2 ] ) = ( ( c * np . cos ( h ) ) , ( c * np . sin ( h ) ) ) return lch
cie-lch to cie-lab color space conversion .