Performance of Algorithms on Simulated Stimuli

As an additional test, we ran all algorithms on input images that were similar to the stimuli used in Helson s experiments. This is particularly important as some of the algorithms operate on a grid of processing elements and the output may not be uniform over the entire sample. Also, some simplifying assumptions had to be made in the theoretical analysis. We will see in a moment that the calculated output colors correspond to the colors that were theoretically computed. 

The color of each input pixel c is obtained by multiplying the reflectance at each pixel with the light given off by the virtual light source  

The perceived color of the 12 input stimuli are shown in Table 14.2, i.e. if the sample has a higher reflectance than the background, then to a human observer the sample appears to have the color of the illuminant. If the sample has the same reflectance as the background, then the sample appears to be achromatic. If the sample has a lower reflectance than the background, then the sample appears to have the complementary color of the illuminant. Table 14.3 shows the performance of the algorithms discussed in Chapters 6 and 7 on the 12 input images. Table 14.4 shows the performance of the algorithms discussed in Chapter 11 

AGREEMENT WITH DATA FROM EXPERIMENTAL PSYCHOLOGY 

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