Overview: Track and programme descriptions

Track and programme descriptions identify available content and provide context for selecting or routing it.

Language labels and default flags help describe a track, while MPEG transport-stream tables identify programmes and their component streams. That information guides interpretation and selection without replacing the player's own policy. This branch is useful when the file's available tracks differ from the language or programme the viewer expected.

• Track language metadata
  Track language metadata identifies the language of an audio or subtitle track for display and selection.

• Default track flags
  Default track flags provide selection hints that players interpret alongside language, accessibility, and user preferences.

• MPEG-TS program tables (PAT and PMT)
  PAT and PMT describe which transport-stream packets belong to each programme and what media those packets carry.