composition d'images

CONT: Image compositing ... that is, combining images to create new images. Porter and Duff [PORT84] suggest that compositing is a good way to produce images in general, since it is fairly easy to do, whereas rendering the individual portions of the image may be difficult. With compositing, if one portion of the image needs alteration, the whole image does not need to be regenerated. Even more important, if some portions of an image are not rendered but have been optically scanned into memory instead, compositing may be the only way to incorporate them in the image.