Hey I'm the author of the project you linked to! The blog post is better for details: http://franklinta.com/2014/10/19/serverless-webrtc-using-qr-...

Flashing qr codes was just a quick hack and actually doesn't work super well. I think if I had more time I would try compressing and stripping down the message more so it would fit in a single qr code instead (like in https://webrtchacks.com/the-minimum-viable-sdp/).