mov mvhd atom - selectionTime and selectionDuration

Hi,


I am wondering how to seve current position and selection range into quicktime movie.


QuickTime Movie format itself have mvhd atom. I know it contains selectionTime, selectionDuration as the last state when saved.

I drilled down AVAsset, AVMovie, AVMutableMovie, but I cannot find such property in them.


Is it possible to keep such setting in quicktime movie file?