the temporal sampling pattern of a sequence of images that represents a moving scene is classified into classes of temporal sampling patterns including “ film ”, “ video ” and “ still ”. pixels in each image in the said sequence are classified according to the relationship between signed inter - image pixel - value differences f 1 and f 2 between that image and , respectively , the preceding and succeeding images in the sequence . an initial classification for each pixel may be refined in accordance with the relative numbers of pixels of the image initially classified into each class .