Steve Lhomme authored Nov 24, 2021 and Jean-Baptiste Kempf committed Nov 27, 2021

The CodecDelay needs to be substracted from the PTS of all frames of that
track. That may result in negative DTS, PTS and PCR which is not well handled.
So we just shift all timestamps based on the biggest CodecDelay so all
timestamps are always positive.

This is in line with how libavformat reports the timestamps on frames from a
track with a CodecDelay.

This is done per segment as other segments may use a different CodecDelay
per track.

Fixes #25129