1. A computer-implemented method for processing regions of interest in imagery of a colon, the method comprising: a) obtaining colonic imagery data relating to the colon; b) detecting at least one candidate colonic residue region in said colonic imagery data; c) for at least one said candidate colonic residue region detected, calculating a feature vector for said region; d) for at least one said candidate colonic residue region detected, for which a feature vector was calculated, determining a class for the said candidate colonic residue region using said feature vector and at least one statistical classifier; and e) for at least one class, outputting to at least one user at least one candidate colonic residue region belonging to said class.