“Media Capture from DOM Elements” document by W3C defines captureStream() method that allows the capture of a <video>/<audio> element in the form of a MediaStream. We want to implement the necessary Blink and Chromium sections that would create this stream by accessing the <video>/<audio> output according to the given play back constraints.
Docs: https://developers.google.com/web/updates/2016/10/capture-stream https://developer.mozilla.org/en-US/docs/Web/API/Media_Streams_API
Samples: https://rawgit.com/Miguelao/demos/master/videoelementcapture.html