Closed Bug 1548113 Opened 8 months ago Closed 8 months ago

mochitest dom/media/test/test_playback.html fails to decode spacestorm-1000Hz-100ms.ogg on RDD


(Core :: Audio/Video: Playback, defect, P2)




Tracking Status
firefox68 --- fixed


(Reporter: mjf, Assigned: mjf)


(Blocks 1 open bug)



(2 files)

When enabling Vorbis decoding on the RDD process, one file in test_playback.html fails: spacestorm-1000Hz-100ms.ogg. In checkEnded[1], checkMetadata fails with a reported duration of 0.256 and the test is looking for 0.099.

I tried loading spacestorm-1000Hz-100ms.ogg into Audacity on macOS, but Audacity fails to open the file. I trimmed small-shot.ogg down to 0.099 length, and it reports the correct length under RDD, so it seems to be specific to spacestorm-1000Hz-100ms.ogg.

The patch to limit the mochitest to only spacestorm-1000Hz-100ms.ogg and pref-on Vorbis on RDD is included for easier debugging.


After some debugging w/ rr, in MediaDecoderStateMachine::UpdatePlaybackPositionPeriodically the call to AudioEndTime() here[1] returns different values depending on whether the decoding the file spacestorm-1000Hz-100ms.ogg is happening on the RDD process or the content process.
Under RDD process, AudioEndTime() returns 256000.
Under content process, AudioEndTime() returns 99000, as the test expects.


Adding a priority to remove from triage queue. Please adjust as appropriate.

Priority: -- → P2
Blocks: RDD

More progress - VorbisDataDecoder::ProcessDecode is getting different frame counts here[1].

Under RDD process, vorbis_synthesis_pcmout returns 256 frames on the second call.
Under content process, vorbis_synthesis_pcmout returns 99 frames on the second call.


More progress - the difference is because VorbisDataDecoder::ProcessDecode is always sending a false here[1]. I believe we're missing initializing mEOS on MediaRawData.


Assignee: nobody → mfroman

Lack of mEOS for decoding Vorbis on RDD was causing a mochitest failure
with file spacestorm-1000Hz-100ms.ogg in dom/media/test/test_playback.html.
The symptom was an incorrect frame count here[1].


Pushed by
pass mEOS from MediaRawData to remote decoder. r=jya
Closed: 8 months ago
Resolution: --- → FIXED
Target Milestone: --- → mozilla68
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