Configuration packets produced by MediaCodec have no valid PTS, and do
not produce frame. Do not queue their (invalid) PTS not to break the
matching between frames and their PTS.
Since PTS handling has been fixed, the recorder do not associate a PTS
to a wrong frame anymore, so PTS of "configuration packets" (which never
produce a frame), are never read by the recorder. Therefore, there is no
need to ignore them explicitly, so we can remove the MediaCodec flags
completely.
On some devices, we can reuse the same codec and display, but on some
others (e.g. Nexus 5X with Android 7.1.2), it crashes on codec.stop()
with an IllegalStateException.
Therefore, always recreate the codec and display, so that it works on
all devices.
Replace screenrecord execution by manual screen encoding using the
MediaCodec API.
The "screenrecord" solution had several drawbacks:
- screenrecord output is buffered, so tiny frames may not be accessible
immediately;
- it did not output a frame until the surface changed, leading to a
black screen on start;
- it is limited to 3 minutes recording, so it needed to be restarted;
- screenrecord added black borders in the video when the requested
dimensions did not preserve aspect-ratio exactly (sometimes
unavoidable since video dimensions must be multiple of 8);
- rotation handling was hacky (killing the process and starting a new
one).
Handling the encoding manually allows to solve all these problems.
Romain Vimont
Ivan Gorinov
Romain Vimont