Detecting and correcting red-eye in a digital image

摘要

Systems and methods of detecting and correcting red-eye in a digital image are described. In one aspect, measures of pixel redness in the digital image are computed. A preliminary set of candidate red-eye pixel areas is identified based on the computed pixel redness measures. Each candidate red-eye pixel area having a computed redness contrast relative to at least one respective neighboring pixel area less than a prescribed redness contrast threshold is filtered from the preliminary set. In addition, each candidate red-eye pixel area located in an area of the digital image having a computed grayscale contrast relative to at least one respective neighboring pixel area less than a prescribed grayscale contrast threshold is filtered from the preliminary set. In another aspect, at least one candidate red-eye pixel area in the digital image is detected. Pixels in each candidate red-eye pixel area are classified based on redness and skin tone coloration. For each candidate red-eye pixel area, an initial pixel mask identifying all pixels in the candidate red-eye pixel area classified as red and non-skin tone is generated. A final pixel mask is generated based on each initial pixel mask. Red-eye in the digital image is corrected by darkening and desaturating original color values identified as red in the final pixel mask, wherein original color values of pixels identified as red in the final pixel mask are desaturated by respective amounts that vary with pixel location in the final pixel mask.