Our live lightshows images are composite of many video, film, and other projections that are layered onto one area of the screen.  The video clips in the Model A link are an example of this "built up" layering.  For this segment of the Model A show we use three layers of video imagery and two to four layers of film images.  Individually the video clips and film are very simple and don't contain a lot of detail.  They need to be simple so that visual impact is not lost as images are layered.  A good example of simple clips that are designed to loop continuously are shown in the Video A link.