Automatic Picture-in-Picture

[bpkeen]

WebKittens

@marcoscaceres

Title of the proposal

User Agent Initiated (Automatic) Picture-in-Picture

URL to the spec

https://pr-preview.s3.amazonaws.com/bpkeen/picture-in-picture/pull/241.html#automatic-picture-in-picture-request

URL to the spec's repository

https://github.com/w3c/picture-in-picture

Issue Tracker URL

No response

Explainer URL

https://developer.chrome.com/blog/automatic-picture-in-picture-initiated-by-the-browser

TAG Design Review URL

No response

Mozilla standards-positions issue URL

mozilla/standards-positions#1434

WebKit Bugzilla URL

No response

Radar URL

No response

Description

This proposal extends the Picture-in-Picture API to allow the user agent to automatically open a Picture-in-Picture (PiP) window when the original content becomes occluded, such as when a user switches to another tab.

The proposed spec changes were originally created to define a permission policy for this feature, but have now expanded to also formalize what is an "automatic PiP request".

Specifically, when content occlusion occurs, there are two paths:

1. Media Session (Building on EnterPictureInPicture MediaSessionAction w3c/mediasession#294): If the site has registered a MediaSessionActionHandler for the enterpictureinpicture action, the user agent may trigger the action with the contentoccluded reason. This allows the site to customize the PiP experience.
2. User agent: If no handler is registered, the user agent may run the request PiP steps on a desired video element.

Note that above we use "the user agent may", this is to emphasize that the user agent can evaluate additional requirements (e.g. media is playing) to ensure a positive user experience.

The motivation is to provide a seamless multitasking experience when users navigate away from active media or video conferencing apps. For reference, see these articles:

• Automatic picture-in-picture for video conferencing web apps: https://developer.chrome.com/blog/automatic-picture-in-picture
• Enter picture-in-picture automatically when playing media: https://developer.chrome.com/blog/automatic-picture-in-picture-media-playback
• Enter video Picture-in-Picture automatically on more sites: https://developer.chrome.com/blog/automatic-picture-in-picture-initiated-by-the-browser