Contains information about the number of valid frames in a file and where they begin and end.
- iOS 2.0+
- macOS 10.3+
- Mac Catalyst 13.0+
- tvOS 9.0+
Some data formats might have packets with contents that are not completely valid, but that represent priming or remainder frames not intended for playback. For example, a file with 100 packets of AAC is nominally 1024 * 100 = 102400 frames of data. However, the first 2112 frames might be priming frames.
A number of remainder frames might be added to pad out to a full packet of 1024 frames. Discard the priming and remainder frames.
The total number of packets in the file times the frames per packet (or counting each packet's frames individually for a variable frames per packet format) minus
m, should equal