| 摘要 |
PROBLEM TO BE SOLVED: To detect proper gray pixels by using color information obtained from a shape, structure and the like, in a specified image within image data. SOLUTION: A skin-tone image portion contained in an image is detected, based on the shape of the image of a human face. The average value of each of RGB values of pixels that constitute the skin-tone image portion detected is calculated. If the distance between a skin-tone-blackbody locus H and a value that is the result of converting the RGB values, obtained by multiplying the average value by prescribed coefficients is less than a prescribed value, these coefficients are adopted as the coefficients for multiplying the RGB values of each pixel constituting the image. By using a value that is the result of converting, to a chromaticity value, the RGB values, obtained by multiplying the RGB values of each of the pixels constituting the image by the prescribed coefficients, those pixels that have values belonging to a zone in the vicinity of a point on a gray-blackbody locus G that corresponds to a light-source color temperature estimated, based on the skin-tone-blackbody locus H among respective pixels that constitute the image, are treated as gray candidate pixels. COPYRIGHT: (C)2006,JPO&NCIPI |
