I am considering doing online piano instruction, and am wondering how I can combine different video sources on the fly, and either broadcast or save the output.<p>An example of what I am talking about would be https:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=obNAgImLMSI, about 15 seconds in, where an overhead shot of the keyboard appears at the bottom of the screen.  A different type of effect would be this: https:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=stsBqdo9Svc, in which a 2nd keyboard appears showing which keys are being played as well as the note names (which can be difficult to otherwise determine in fast passages).<p>I&#x27;m a good programmer (MS in CS), and don&#x27;t mind getting my hands dirty in a bit of custom coding, but I don&#x27;t even know where to start.  (Don&#x27;t worry, I&#x27;m competent to teach piano, too... I also have a BM in Piano Performance.)  I specialize in teaching the integration of music reading and improvisation, and have had many requests to teach long distance, but I have never done so because I do not feel as though I have the proper tools to do it justice.<p>I would love to find an Open Source solution that I could contribute back to, if possible.<p>Does anyone have any ideas&#x2F;recommendations?
Ask HN: What tools exist to do live video manipulation for streaming/recording?