Can we use the Web Speech API in Google Chrome to recognize speech coming from other sources than the user’s microphone?

I would like to use the Web Speech API in Google Chrome to recognize speech coming from a HTML5 <video> on a web page. Is there a way to use the Web Speech API with an audio input coming from somewhere else than the user’s microphone?

On MDN (developer.mozilla.org/en-US/docs/Web/API/Web_Speech_API) it says:

Speech recognition is accessed via the SpeechRecognition interface, which provides the ability to recognize voice context from an audio input (normally via the device’s default speech recognition service)

But it does not clearly specify if this audio input can come from somewhere else than the user’s microphone, or if it must come exclusively from the user’s microphone.