Two defects:
- Ac3Parser inherited the no-op default flush(), so a complete final
frame still buffered at end-of-stream was dropped (~32 ms of audio
lost). Add a flush() that drains a complete buffered frame, mirroring
dts.rs.
- Every frame in one parse() call was stamped with the single PES PTS,
collapsing their timecodes and drifting A/V. Compute a base PTS once
per call, then advance per frame by the frame's own duration (AC-3 =
1536 samples; E-AC-3 from numblkscod), converting samples->ns at the
stream sample rate (fscod). Each Frame now carries duration_ns.
MattJackson
77f7aced83