Ingineria Iluminatului - Journal of Lighting Engineering - Prof. Florin ...

Figure 5 Colour samples of the background Figure 6 Visual experiment in the booth
5. PERCEIVED ATTRIBUTES AND METRIC QUANTITIES
The perceived hues, chromas and lightnesses evaluated by the observers are compared with the metric hues, chromas and
lightnesses in U*V*W*, L*a*b*, Nayatani, Hunt, CIECAM97s and NC-IIIC spaces as shown in Figure 7 to 11.
Colorimetric quantities of test colour samples prescribed in Munsell colour system under various light sources are
calculated from the spectral reflectance of each test colour sample.
Perceived attributes of the test colours are compared with the metric quantities in accordance with following
procedures.
(1) Mean separations between the metric hues and the perceived hues.
(2) Average deviations of the metric chromas from the perceived chromas.
(3) Mean distances of the metric lightnesses from the perceived lightnesses.
(4) Total dislocations of the metric quantities from the perceived attributes.
Perceived attributes of colour appearances are desired to be predicted appropriately by corresponding metric
quantities in a proper colour space or an adequate colour appearance model.
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