Abstract
Chromatic contrast occurs when a color patch is surrounded by a chromatic field [1,2]. Several studies demonstrate the importance of variation within the surrounding field, in addition to the effect of chromaticity of the field on color appearance [3,4,5,6].
The chromatic appearance of a target is tested under an equilibrium condition resulting from the effect of two inductive stimuli: a large peripheral color inducing field which produces a strong color induction, and an imbedded neighboring surround which counterbalances the strong induction generated by the periphery. The chromatic appearance of the target (specified in terms of L-, M-, S-cone excitation signals) is assessed according to a hue cancellation judgment. Various surrounds similar in terms of average chromaticity and different in terms of spatial contrast were derived from a natural image by pixel randomizing, by pixel ordering and by averaging the chromaticity.
Results show that the surrounds vary in their efficiency to counterbalance the strong induction generated by the peripheral color field. The statistics of the pixel randomized image seems to be the most powerful to counterbalance peripheral induction. Also, there is no obvious difference between pixel reorganized scenes and pixel averaged scenes to regulate contrast. This means that, in our experiment, the high chromatic contrast amplitude is not more efficient than uniform patches to control chromatic induction.
To conclude, although every neighboring scene has the same average chromatic content, the resulting color appearance of the target differs between scenes. The less efficient scenes for contrast regulation are those which present the most disparate effects of proximity. Then, it is not the image frequential structure that matters but the structure of proximity.