The key frame requester re-armed its timer on every loop, so every video down
track woke up every 200 ms to 1 s for its whole life, even when the layer was
locked and there was nothing to do.
Re-arm the timer only while the requested layer is not locked, or while the
lock can change without an event: an acquisition grace is armed, or layers are
selected with the dependency descriptor, which can lose the lock on the packet
path. Post the event on resync, mute, max published layer change and packet
path layer switch, since those can change the lock without an allocation.
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
VP9 SVC sends each spatial layer as its own encoded frame,
so a picture carries one trailer per layer, but only the
top layer's last packet has the RTP marker bit set.
Fix https://github.com/livekit/egress/issues/1347
* Tests for down stream packet push.
A recent issue (padding bit in RTP header) surfaced a gap which slipped
through due to lack of tests. Changes in pion/rtp were not adopted
properly.
So, adding some tests (thank you Claude for the heavy lifting) to test
the down stream packet path using the whole pion chain.
Split out some interfaces so it is easier to have it all in one place
and create fakes.
Will help adding more tests, for example include the upstream path also
in the integration test. May have to create more interfaces and make
things testable, but this is a start.
* missed file
* rtx specific test
Raja Subramanian