TONE-CONVERSION DEVICE FOR IMAGE, PROGRAM, ELECTRONIC CAMERA, AND TONE-CONVERSION METHOD

摘要

PROBLEM TO BE SOLVED: To generate with small processing load a conversion gain map k[i, j] suitable for a detailed tone adjustment. SOLUTION: The present invention relates to a tone-conversion device for converting a tone of an image having an achromatic signal and a chromatic signal, and it includes: a signal extracting unit defining an achromatic signal of a first pixel or an extremely adjacent second pixel from a plurality of pixels as an achromatic signal value; a neighborhood processing unit generating a local signal of the first pixel according to the achromatic signal and the chromatic signal of a third pixel contained in the neighborhood area which is larger than the second pixel; a gain determining unit determining a conversion gain for the first pixel according to the achromatic signal value and the local signal; and a tone conversion unit performing tone conversion by multiplying the signal component of the first pixel by the conversion gain. COPYRIGHT: (C)2007,JPO&INPIT