A Basic Guide to Transport StreamsTransport Stream Structure
TablesThere are two essential tables in a Transport Stream:
A programme can be thought of a Television Channel and the Transport stream contains all the channels for a particular frequency.
There is only 1 PAT in a transport stream and it has the PID value of 0.
Below is a typical structure showing a PAT with just 1 programme (PMT) which just has a single Video stream, an audio stream and points to a stream specifically for the reference clock (PCR).
In the next example, there are multiple Programmes (PMTs) under the PAT
The items in red are streams that are missing from the source file but are included in the PMT.
Below shows a decode of a typical PMT:
There are 3 important items in the decode window:
- PCR PID (0x1FFE)
- Video Stream (0x244)
- Audio Stream (0x245)
TSPE can correct the PMT tables to point to the correct PCR PID and to remove missing streams that are present in the PMT but not in the stream (coloured red in the above example).