MPEG-4 systems
MPEG-4

The MPEG-4 standard not only saw the development of new tools for coding audio and video, but also new systems (figure 22), to enable new functionalities. It is true that an MPEG-2 TS (Transport Stream) data stream can be stored, but it is recorded in the same way as it is transmitted, which inhibits applications such as search. Similarly, with MPEG-2 TS, the protection system is limited to signalling access control and transporting the encrypted "keys" needed to descramble images and sounds. Developments in MPEG-4 systems concern in particular :

• distribution (§ 2.1