I have a created a music visualisation using Processing. I now want to convert that to a video, and the least obtrusive way I could think of is to record a screencast.

I figured exporting Processing to video including audio, from within Processing itself, on ubuntu seemed an unsolved issue. Very hard and also could cause timing sync issues (since the music keeps running while images are captured). So move on to the screencast method.

Dead-easy, I figured. But I was wrong. First hurdle was to find a way to record the sound from the audio (and not the mic).

I did find a tutorial for that here.

In short: use gtk-recordmydesktop and pulse audio. But, apparently, what happens: Processing does not use ALSA. When the sound is playing, it does not appear in the Pulse Audio mixer.

How can I record the audio now?