An apparatus and method for storing and playing high definition content is disclosed. This invention provides a mechanism for storing and playing back high definition content on a medium such as DVD optical disc. One aspect of the invention is that elementary streams may be multiplexed and processed in a high definition media player instead of at authoring time. Another aspect of the invention is that it provides for extended real-time features such as inserting watermarks into the content stream, decrypting selected sections of the content stream, and performing trick playback display modes.