Adds support for hard constant bitrate (CBR) mode of the Opus encoder when CBR mode is used for MediaRecorder. Without this change it is impossible to encode compressed constant bitrate audio files with the MediaRecorder. This implements a spec change allowing either constant bitrate (CBR) or variable bitrate (VBR) encoding on the MediaRecorderOptions object passed to the MediaRecorder constructor. Previously VBR was assumed when using anything other than uncompressed PCM.

Motivation

Documentation

• https://w3c.github.io/mediacapture-record/#mediarecorder-api

Specification

Editor's draft

Status in Chromium

Blink components: Blink>MediaRecording

Enabled by default (tracking bug) in:

• Chrome for desktop release 89
• Chrome for Android release 89
• Android WebView release 89

Consensus & Standardization

• Firefox: No signal
• Edge: No signal
• Safari: Positive
• Web Developers: No signals

Owner

• simon.jackson@sonocent.com

Intent to Prototype url

Comments

PR to address TAG issues: https://github.com/w3c/mediacapture-record/pull/210

Last updated on 2021-04-13