In my [limited] experience with CBIR and image based search, I found that using a color space with perceptual spatial qualities (such as one of the CIE LaB vari

In my [limited] experience with CBIR and image based search, I found that using a color space with perceptual spatial qualities (such as one of the CIE LaB variants) to be more effective than a purely normalized geometric color space (such as RGB or HSV), as color similarities in the latter may not make much sense to a human.