Intent to Ship: Support restrictOwnAudio

[Chromestatus]

Contact emails

brand...@google.com

Explainer

https://github.com/guidou/mediacapture-screen-share/blob/gh-pages/explainer-restrictOwnAudio.md

Specification

https://www.w3.org/TR/screen-capture/#dfn-restrictownaudio

Summary

restrictOwnAudio is a captured display surfaces constrainable property. This constrainable property changes the behavior of system audio in a captured display surface. The restrictOwnAudio constraint will only have an effect if the captured display surface inherently includes system audio; otherwise, it will have no impact. By default, when system audio is captured, it includes all audio played out by the system on audio output devices. When restrictOwnAudio is enabled, the captured system audio will be filtered to exclude audio originating from the document that performed getDisplayMedia. The restrictOwnAudio constraint allows for cleaner screen recordings for some use cases. Without it, if the capturing web page itself is playing audio (e.g. a video embedded on the on the recording page), that audio would be included in the capture. This could lead to an undesirable echo or interfere with the intended audio sources from other tabs or applications. The restrictOwnAudio constrainable property is described in the specification. https://www.w3.org/TR/screen-capture/#dfn-restrictownaudio

Blink component

Blink>GetDisplayMedia

TAG review

https://github.com/w3ctag/design-reviews/issues/1109

TAG review status

Issues addressed

Risks

Interoperability and Compatibility

None

Gecko: No signal (https://github.com/mozilla/standards-positions/issues/1244) This has been part of the spec for a long time, which has consensus among all major browser vendors.

WebKit: No signal (https://github.com/WebKit/standards-positions/issues/511) This has been part of the spec for a long time, which has consensus among all major browser vendors.

Web developers: No signals

Other signals:

WebView application risks

Does this intent deprecate or change behavior of existing APIs, such that it has potentially high risk for Android WebView-based applications?

None

Debuggability

None

Will this feature be supported on all six Blink platforms (Windows, Mac, Linux, ChromeOS, Android, and Android WebView)?

No

Is this feature fully tested by web-platform-tests?

No

Flag name on about://flags

N/A

Finch feature name

RestrictOwnAudio

Rollout plan

Will ship enabled for all users

Requires code in //chrome?

False

Adoption expectation

Feature is used by specific partner(s) to provide functionality within 12 months of launch in Chrome.

Estimated milestones

Shipping on desktop	140
Shipping on Android	140
Shipping on WebView	140

Anticipated spec changes

Open questions about a feature may be a source of future web compat or interop issues. Please list open issues (e.g. links to known github issues in the project for the feature specification) whose resolution may introduce web compat/interop risk (e.g., changing to naming or structure of the API in a non-backward-compatible way).

None

Link to entry on the Chrome Platform Status

https://chromestatus.com/feature/5128140732760064?gate=5969936572481536

Links to previous Intent discussions

Intent to Prototype: https://groups.google.com/a/chromium.org/d/msgid/blink-dev/6830541c.170a0220.2aa17e.1583.GAE%40google.com

This intent message was generated by Chrome Platform Status.

[Dan Clark]

> Will this feature be supported on all six Blink platforms (Windows, Mac, Linux, ChromeOS, Android, and Android WebView)?

> No

My understanding is that this has to be "No" because getDisplayMedia is not supported on all platforms, but can you confirm it will ship everywhere that getDisplayMedia is supported?

> Is this feature fully tested by web-platform-tests?

> No

I get that there will be limitations about how effectively this can be tested in a WPT, but would it make sense to add some basic checks that the feature is supported?

suppressLocalAudioPlayback seems kind of similar and I see there are a couple tests for that at https://github.com/web-platform-tests/wpt/blob/6ef3efe286a2b4bd5f32e5e529d044be12db1347/screen-capture/getdisplaymedia.https.html#L237.

Thanks,

Dan

[olka via Chromestatus]

WPT added: https://source.chromium.org/chromium/chromium/src/+/main:third_party/blink/web_tests/external/wpt/screen-capture/getdisplaymedia-restrictOwnAudio.https.html The feature is shipping on Win and Mac only, as Linux and ChromeOS do not provide the required functionality at this time.

[Olga Sharonova]

Hi Dan,

 

> Will this feature be supported on all six Blink platforms (Windows, Mac, Linux, ChromeOS, Android, and Android WebView)?

> No

My understanding is that this has to be "No" because getDisplayMedia is not supported on all platforms, but can you confirm it will ship everywhere that getDisplayMedia is supported?

It will be supported on Windows and Mac, and won't be supported on CromeOS and Linux - due to those platforms not providing the required functionality at this time. 

 

> Is this feature fully tested by web-platform-tests?

> No

I get that there will be limitations about how effectively this can be tested in a WPT, but would it make sense to add some basic checks that the feature is supported?

suppressLocalAudioPlayback seems kind of similar and I see there are a couple tests for that at https://github.com/web-platform-tests/wpt/blob/6ef3efe286a2b4bd5f32e5e529d044be12db1347/screen-capture/getdisplaymedia.https.html#L237.

Thank you, this is a good point. Added new tests here https://source.chromium.org/chromium/chromium/src/+/main:third_party/blink/web_tests/external/wpt/screen-capture/getdisplaymedia-restrictOwnAudio.https.html.

 

Olga

[Alex Russell]

LGTM1

[Chris Harrelson]

LGTM2

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[Yoav Weiss (@Shopify)]

LGTM3

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