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Explainer None Specification https://www.w3.org/TR/webcodecs Summary Introduces "rotation: int" and "flip: bool" values to various video related interfaces in WebCodecs so that developers can work with frame sources that have orientation (Eg, Android cameras, certain media). The VideoFrame interface grows the ability to create VideoFrames with arbitrary rotation and flip as well as accessors for this information on the VideoFrame object. The VideoDecoderConfig object gains rotation and flip fields that are emitted on decoded VideoFrame objects automatically. The VideoEncoder class gains mechanisms for passing rotation and flip information from encode() to the VideoDecoderConfig emitted as part of EncodedVideoChunkMetadata. If encode() is called with frames with different orientations a non-fatal exception will be thrown. configure() may be used to reset the allowed orientation. Blink component Blink>Media>WebCodecs Search tags webcodecs, videoframe, orientation, videodecoder, videoencoder TAG review None TAG review status Not applicable Risks Interoperability and Compatibility Low, feature designed in conjunction with Firefox and the Media WG. Gecko: Positive (https://bugzilla.mozilla.org/show_bug.cgi?id=1955904) Spec co-editor, approved all spec changes, implementation planned. WebKit: No signal (https://github.com/WebKit/standards-positions/issues/475) Participated in some of the standards discussions around this feature. Web developers: Positive (https://github.com/w3c/webcodecs/issues/351) Active requests from Zoom and others developers (see issue) who are working with cameras with orientation metadata. Other signals: Ergonomics No risk. Small incremental change to WebCodecs API. Activation No risk. Small incremental change to WebCodecs API. MDN documentation will be updated. Security No risk. No new control surfaces. Video elements already have this functionality. 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? Some cameras and media will immediately begin exposing orientation information. In uncommon cases this orientation may change. If orientation changes during encoding through VideoEncoder frames with different orientation than the first are currently encoded with incorrect size and orientation. However the operation completes without a hard error. During discussions in the media working group it was decided that these cases should instead throw a non-fatal exception during encode(). There is already precedent for exception handling during encode() so authors should already be handling this case. Debuggability Rotation information shows up in media configs emitted in media dev tools. Will this feature be supported on all six Blink platforms (Windows, Mac, Linux, ChromeOS, Android, and Android WebView)? Yes Mostly just exposes existing under the hood information used by video elements, so is already supported everywhere. Is this feature fully tested by web-platform-tests? Yes https://wpt.fyi/results/webcodecs?label=master&label=experimental&aligned&q=orientation Flag name on about://flags WebCodecsOrientation Finch feature name WebCodecsOrientation Requires code in //chrome? False Tracking bug https://crbug.com/40243431 Measurement WebCodecs has use counters, but no specific use counter has been added for the rotation and flip usage. Availability expectation Available on all platforms except for iOS. Adoption expectation Should be adopted by sites consuming camera feeds with WebCodecs. Estimated milestones Shipping on desktop 137 DevTrial on desktop 136 Shipping on Android 137 DevTrial on Android 136 Shipping on WebView 137 Anticipated spec changes Open questions about a feature may be a source of future web compat or interop issues. Please list open issues (eg links to known github issues in the project for the feature specification) whose resolution may introduce web compat/interop risk (eg, changing to naming or structure of the API in a non-backward-compatible way). Spec changes have already been landed after review with Firefox and the Media Working Group: * https://github.com/w3c/webcodecs/pull/884 * https://github.com/w3c/webcodecs/pull/874 * https://github.com/w3c/webcodecs/pull/840 * https://github.com/w3c/webcodecs/pull/559 Link to entry on the Chrome Platform Status https://chromestatus.com/feature/5128855343595520?gate=5187346531876864 This intent message was generated by Chrome Platform Status. -- You received this message because you are subscribed to the Google Groups "blink-dev" group. To unsubscribe from this group and stop receiving emails from it, send an email to blink-dev+unsubscr...@chromium.org. To view this discussion visit https://groups.google.com/a/chromium.org/d/msgid/blink-dev/67e2d562.170a0220.e1a1e.07a6.GAE%40google.com.
