Besides. the spectral sensitivity of the sensors used in different digital cameras
does not matclt each other. llence, the RGB responses are not colorimetric.
Consequently, a color transform between device dependent RGB signals to device
independent tristimulus values such as XYZ or CIELAB is required for color
reproduction by taking account of the digital camera spectral sensitivities, illumination
and encoding color space (Hong et al., 2000, lSOl732l-I, 2006). 'I'hese transform
process is known as camera Characterization.