Just noticeable difference of image attributes for natural images

To model the relative importance of the image quality attributes white level, black level, color saturation and contour rendering, they need to be varied all to a perceptually equal extent. The just noticeable difference (JND) of each attribute can be used for this. These JNDs are well known for specific test patterns, but not for natural image content. In this paper, we describe several experiments to determine the relationship between the JNDs and the averaged image characteristics.