*MPEG-2 : Overview of the systems layer

Summary The MPEG-2 Systems specification describes how MPEG-compressed video and audio data streams may be multiplexed together with other data to form a single data stream suitable for digital transmission or storage. This Report introduces the principles and terminology of the MPEG-2 Systems layer. The Report covers three main areas: Firstly, the structure of the multiplexes; secondly, the service information that may be present; thirdly, the system of time stamps and clock references used to synchronise related components of a programme at the decoder. Two alternative multiplexes are specified for the MPEG-2 systems layer. The programme stream is biased towards the storage and replay of a single programme from a digital storage device while the transport stream is intended for the simultaneous delivery of a number of programmes over potentially error-prone channels. Both multiplexes facilitate the inclusion of Programme Specific Information detailing the programme(s) and elementary streams present. The multiplexes also use a system of time stamps and clock references to ensure the synchronous replay of related elementary streams and correct buffer behaviour at a decoder. There are many optional syntax elements and many opportunities to include private (user-defined) syntax extensions enabling either multiplex to be optimised to suit a particular application. * This Report is based on two papers prepared for the Institution of Electrical Engineers (IEE) and is published with permission. The papers were written and used by BBC RD firstly, for the IEE Colloquium at Savoy Place (Jan. 1995):- MPEG-2: A tutorial