What is carried in MPEG-2 Transport Streams?

MPEG-2 Transport Streams carry transport packets. These packets carry two types of information: the compressed material and the associated signalling tables. A transport packet is identified by its PID (Packet Identifier). Each PID is assigned to carry data belonging either to one particular compressed data source (and only this data source) or one particular signalling table. The ordered sequence of packets with a given PID may be considered as one data stream. The compressed data source may be derived from either video, audio or data elementary streams. These elementary streams may be tightly synchronized (as it is usually necessary for Digital TV programs, or for Digital Radio programs), or not synchronised (in the case of programs offering downloading of software or games, as an example). The associated signalling tables consist of the description of the elementary streams which are combined to build programs, and in the description of those programs. Tables are carried in ...  more