This development is based on temporal compression that compares each frame of video to the following frame and only stores the changes in the scene. It stores a single frame in a delay so as to continually put out the background of a scene and have more room to store the changes in the scene. MPEG2 also uses the discrete cosine transform , which takes images and finds their frequency and then compresses any repetitive frequencies. Video compression allows more room to store additional viewing options, a big part of what makes DVD such an incredible advancement in technology. DVD video can also let the viewer decide the rating, R or PG, thanks to preprogrammed scene cuts on the disc itself.
Viewers can also opt to watch an uncut version of the film or see out takes from the original.
All of these selections can be chosen at the start of the film. The DVD then makes seamless skips from one scene to the next in the arrangement the viewer has chosen. The director and the producer decide upon the amount and type of options available, so each individual DVD may have some, all or none of these options. Another big improvement of DVD video storage is its 525-line resolution, which is far greater than the resolution offered by laser disc media and almost twice the resolution of standard VHS videotape. One more advantage is that a DVD disc is not physically touched while it spins in the player, so there is no wear and tear or loss of fidelity over time.