Edited by author 10-26-2006 04:15 PM
to Paul: There exist CSIFT:A SIFT Descriptor with Color Invariant Characteristics - For some reason is not that popular..maybe because adding color made the computation a lot heavier and the robustness gained is not that much compared with the traditional SIFT.

About the paper: I wonder how this would change if the backgrounds the corridors have constant traffic of people and maybe a bit more cluttered background?. Color histograms and CCCM seems to look pretty well using the links on this uniform corridors.