MPEG-2 has two different multiplexing schemes: Program Stream and Transport Stream.
The Program Streams are mostly used in storage applications. Broadcast usage commonly uses the Transport Stream format. If you have one content channel (one program), it does NOT imply that the stream that carries the program would be a Program Stream. In broadcast usage it would be a so-called Single Program Transport Stream (as defined by ISO 13818-1): a multiplexed collection of concatenated Program Streams without beginning or end. VBrick currently only supports Transport Stream which is superior to Program Stream for streaming applications.
* An MPEG-2 Program Stream contains one, and only one, content channel. A Program Stream is like a single-passenger car without shock absorbers: drive it on a smooth road.
* An MPEG-2 Transport Stream can contain one or more content channels. A Transport Stream is like a high end car or bus: it can carry one or more passengers and has a good suspension system that can handle the bumps in the road. VBrick supports Single Program Transport Stream, so this is like a single passenger car with good suspension.
MPEG-2 Multiplexing
The MPEG-2 standard allows two forms of multiplexing:
* MPEG Program Stream A group of tightly coupled PES packets referenced to the same time base. Such streams are suited for transmission in a relatively error-free environment and enable easy software processing of the received data. This form of multiplexing is used for video playback and for some network applications.
* MPEG Transport Stream Each PES packet is broken into fixed-sized transport packets forming a general purpose way of combining one or more streams, possibly with independent time bases. This is suited for transmission in which there may be potential packet loss or corruption by noise, or / and where there is a need to send more than one program at a time.
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