source_id [ATSC Semantics]
source_id has a rather simple purpose: to permit linkage between virtual channels, Event Information table entries, and Extended Event Text tables.
valid source_id values
| source_id | description |
| 0 / 0x0000 | Can only be used in SVCT and CVCT entries to signal "source is not identified" |
1-4095
0x0001- 0x0FFF | User Defined (unique within transport stream) |
|