カラーネガフィルムからのボケ画像の検出

抄録

In the photographic printing process, it is important to reject blurred images on color negative films. This is usually done by the judgement of photofinishing expert. Therefore, it is necessary to detect blurred images automatically for a better productivity in the printing operation. Although it is well known that the degree of image sharpness can be evaluated by MTF or acutance, one cannot always expect that every image contains a sharp point image or suitable edges. There is still another problem of judging if the main subject in the image be in focus. We propose a new practical measure of image sharpness which is calculated from the delta histogram for the skin color region in the image, assuming that the human faces be the majority of the main subject.