Determining visually noticeable differences between two images

摘要

The present invention relates to a method and apparatus for determining visually noticeable differences between two input images. A first contrast image is generated from the first input image and a second contrast image is generated from the second input image. A contrast difference image is then formed from the two contrast images. Measures are calculated of the mean absolute difference between blocks of pixels of the first and second input image. Pixels in the contrast difference image are selected which exceed a first threshold and measures of the mean absolute difference are selected which exceed a second threshold. A detection signal is produced from the threshold signals. <IMAGE>