Why an MPEG systems standard is needed to packetize video and audio and what kind of problems such a standard is required to meet.
The need for systems technology for audiovisual applications arises from the wish to combine multiple elementary audio and/or video streams into a single system stream in a manner independent of the transport medium. Though it is possible to provide audio and video as parallel streams, it is in many situations far more practical to provide a single stream that contains audio and video. For example:
Therefore MPEG decided to address combining audio and video into a single system stream. A simple example of combining an audio stream and a video stream into a system stream is presented in Figure 5.1.
In Figure 5.1, the audio and video streams are depicted as byte streams. In the system stream there are ...