HardwareFallbackTest is the only automated check of the hardware->software
fallback against a real codec failure, and it passed on every CI leg
without ever attempting the hardware path.
Measured on run 34004304566: the API 33, 34, 35 and 37 legs each log
Routing sample_h264_444.mp4 -> ... via FFMPEG (NO_HARDWARE_ENCODER)
Emulators expose no hardware encoder, so the router never chooses Media3
and runMedia3OrFallBack's catch is never entered. The test's assertions --
succeeded, output non-empty -- are true of that conversion too. It
finished in 448 ms, which is not long enough to fail an export and then
software-encode a three-second clip. Deleting the catch reddened nothing.
The ticket offered two fixes and left the choice open. Trying the first
one answered it, and not the way the ticket expected. Pinning
deviceCodecs to PERMISSIVE, as ForcedFailureTest does, makes the router
choose Media3 -- and the export then SUCCEEDS. On a local API 34
emulator, MediaCodecInfo logs
NoSupport [codec.profileLevel, avc1.F4000C, video/avc]
for both c2.goldfish.h264.decoder and c2.android.avc.decoder, and
ExoPlayer allocates the goldfish decoder anyway, which decodes the High
4:4:4 fixture regardless of the profile it declares. c2.android.hevc.encoder
then encodes it and the job reports MEDIA3.
So the class KDoc's "Media3 fails partway through the export on every
device" is not true of the emulator images, and no routing pressure makes
this fixture force a fallback there. Pinning would also swap in software
codecs, which is not the path a real device takes -- it is what made the
forced run succeed.
That leaves assumeTrue on the production premise as the honest answer, now
with a measurement behind it rather than a coin flip. The test skips where
it cannot mean anything and runs on the Pixel, where it always could.
When it does run the assertion is a pair, because KEY_ENGINE_USED is
FFMPEG whether the fallback fired or the router went straight there:
the router chose MEDIA3 for this request on this device, AND the worker
reported FFMPEG. Together, and only together, that is the fallback.
Verified on a local API 34 emulator: the test reports SKIPPED and the
level reports skipped=3. ForcedFailureTest still covers the fallback
wiring on every leg with a double; what needs a real encoder is two real
engines disagreeing about a real file.
The third permanent skip is recorded in docs/local-emulator.md and beside
SafPickerRoundTripTest's run-shape note.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
JMR-devandClaude Opus 5
ba16f5a89b