1523563 - MediaRecorder cannot record audio-only webm

Status: RESOLVED FIXED

(Core :: Audio/Video: Recording, enhancement, P3)

Description

[Andreas Pehrson [:pehrsons]]

The EbmlComposer that writes webm clusters refuses to flush a cluster unless a VP8 keyframe has been encoded, even if we're doing an audio-only recording.

Comment 1

[Andreas Pehrson [:pehrsons]]

Attachment: Bug 1523563 - Modernize test_mr_record_audionode.html. r?jib

Comment 2

[Andreas Pehrson [:pehrsons]]

Attachment: Bug 1523563 - Test all mime types with audio node recording. r?jib

Depends on D35169

Comment 3

[Andreas Pehrson [:pehrsons]]

Attachment: Bug 1523563 - Pass in mime type to MediaEncoder and give preference to it when passed. r?jib

Somewhere along the way this must have gotten broken.
Until this, passing mime type to MediaRecorder has had no effect.

This patch does two things:

1. Passes the mime type through from MediaRecorder to MediaEncoder
2. Gives preference to the mime type when passed, wrt picking codecs,
   however, we still yield to a video mime type when given a video track
   since that's how both Firefox and Chromium function today.

Proper spec handling of mime type will be fixed in bug 1512175.

Depends on D35170

Comment 4

[Andreas Pehrson [:pehrsons]]

Attachment: Bug 1523563 - Make mochitests pass with new video/webm fallback. r?jib

From the previous patch, if ogg is disabled we'll fallback on video/webm.
So some tests relying on errors need it disabled too, in order to pass.

Depends on D35171

Comment 5

[Andreas Pehrson [:pehrsons]]

Attachment: Bug 1523563 - Make sense of EbmlComposer. r?bryce

This does two things:

• Makes the code for how flushing works actually readable (seriously).
• Allows audio-only webms.

Depends on D35172

Comment 6

[Andreas Pehrson [:pehrsons]]

Attachment: Bug 1523563 - Modernize test_gUM_audioCapture.html somewhat. r?jib

Depends on D35173

Comment 8

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/e431e395e20e
Modernize test_mr_record_audionode.html. r=jib
https://hg.mozilla.org/integration/autoland/rev/944da9f033e8
Test all mime types with audio node recording. r=jib
https://hg.mozilla.org/integration/autoland/rev/7c42061bf905
Pass in mime type to MediaEncoder and give preference to it when passed. r=jib
https://hg.mozilla.org/integration/autoland/rev/f5a1371cca6e
Make mochitests pass with new video/webm fallback. r=jib
https://hg.mozilla.org/integration/autoland/rev/6c52ecd21b30
Make sense of EbmlComposer. r=bryce
https://hg.mozilla.org/integration/autoland/rev/d9f2bc3dd281
Modernize test_gUM_audioCapture.html somewhat. r=jib

Comment 9

[Cosmin Sabou [:CosminS]]

https://hg.mozilla.org/mozilla-central/rev/e431e395e20e
https://hg.mozilla.org/mozilla-central/rev/944da9f033e8
https://hg.mozilla.org/mozilla-central/rev/7c42061bf905
https://hg.mozilla.org/mozilla-central/rev/f5a1371cca6e
https://hg.mozilla.org/mozilla-central/rev/6c52ecd21b30
https://hg.mozilla.org/mozilla-central/rev/d9f2bc3dd281