Recall that applications may currently obtain a capture of the tab in which they run using getDisplayMedia, either with or without preferCurrentTab. Moreover, soon another API will allow similar functionality - getViewportMedia. In either case, the application may then also wish to crop the resulting video track so as to remove some content from it (typically before sharing it remotely). We introduce a performant and robust API for cropping a self-capture video track.
Applications need a performant and robust way to crop video tracks.
For example, applications that combine video-conferencing and productivity-suite may wish to capture themselves, but only send the productivity-suite portion of themselves to remote participants, thereby avoiding a hall-of-mirrors effect.