the invention provides a method and apparatus for coding information that is specially adapted for smaller presentation formats , such as in a hand held video player . the invention addresses , inter alia , reducing the complexity of video decoding , implementation of an mp3 decoder using fixed point arithmetic , fast ycbcr to rgb conversion , encapsulation of a video stream and an mp3 audio stream into an avi file , storing menu navigation and dvd subpicture information on a memory card , synchronization of audio and video stream , encryption of keys that are used for decryption of multimedia data , and very user interface adaptations for a hand held video player that implements the improved coding invention herein disclosed .