Predicting Visible Image Degradation by Colour Image Difference Formulae

We carried out a CRT monitor based psychophysical experiment to investigate the quality of three colour image difference metrics, the CIEΔE ab equation, the iCAM and the S-CIELAB metrics. Six original images were reproduced through six gamut mapping algorithms for the observer experiment. The result indicates that the colour image difference calculated by each metric does not directly relate to perceived image difference.