Capturing currently playing audio from HTML5?
Is there a way to grab a sound card currently playing audio using getUserMedia? As with what sound is currently being played on the system. I'm pretty sure he can only access the microphone. I don't know if you can access the current output of the soundcard without inserting the input to the output with something like soundflower.
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The getUserMedia method is part of the html5 media-capture-streams specification, it will return the provided MediaStream object (user / browser). The output (or your default playback device) will not, or rather should not be available, since it is not a capture / input device. So, as you mentioned in your question, the way you could do this is to use something like "soundflower" or "virtual audio cables" to relay the output you want to a virtual input and capture that.
W3 Specification: http://www.w3.org/TR/mediacapture-streams/
Alternative Apps: http://alternativeto.net/software/soundflower/
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