- From: Jan-Ivar Bruaroey via GitHub <sysbot+gh@w3.org>
- Date: Fri, 10 Mar 2023 22:58:25 +0000
- To: public-webrtc@w3.org
jan-ivar has just submitted a new pull request for https://github.com/w3c/webrtc-pc: == Fix scaleResolutionDownBy explanatory prose to match normative algorithm == The description of [scaleResolutionDownBy](https://w3c.github.io/webrtc-pc/#dom-rtcrtpencodingparameters-scaleresolutiondownby) is nonsense: _"scaling is applied by a factor of two to the power of the layer's number, in order of smaller to higher resolutions, e.g. 4:2:1"_ ... because as described that would yield 1:2:4 (or 2:4:8). This PR fixes the language to match the normative algorithms: - [sRD](https://w3c.github.io/webrtc-pc/#set-description): _"If proposedSendEncodings is non-empty, set each encoding's [scaleResolutionDownBy](https://w3c.github.io/webrtc-pc/#dom-rtcrtpencodingparameters-scaleresolutiondownby) to 2^(length of proposedSendEncodings - encoding index - 1)."_ - [addTransceiver](https://w3c.github.io/webrtc-pc/#dom-rtcpeerconnection-addtransceiver): _"add a [scaleResolutionDownBy](https://w3c.github.io/webrtc-pc/#dom-rtcrtpencodingparameters-scaleresolutiondownby) member with the value 2^(length of sendEncodings - encoding index - 1). This results in smaller-to-larger resolutions where the last encoding has no scaling applied to it, e.g. 4:2:1 if the length is 3."_ Normative algorithms here clearly trump attribute descriptions, so I'm marking this `Editorial`. See https://github.com/w3c/webrtc-pc/pull/2836 -- Sent via github-notify-ml as configured in https://github.com/w3c/github-notify-ml-config
Received on Friday, 10 March 2023 22:58:26 UTC