1. An apparatus, comprising: means for setting scanning properties of images to be scanned in a pre-scanning operation; means for comparing the images including comparing at least a portion of one of the images with at least a portion of another one of the images to determine whether the images share a common scan line and, if so, classify the images into a same group; means for assigning ones of the images that belong to the same group to a scanning region; and means for initializing a scanning operation corresponding to the scanning region.