The best open source alternative to Wistia is DTube, which is both free and Open Source. If that doesn't suit you, our users have ranked more than 50 alternatives to Wistia and four of them is open source so hopefully you can find a suitable replacement. Other interesting open source alternatives to Wistia are YouPHPTube (Free, Open Source), DevTube (Free, Open Source) and RockMeAmade.us (Free, Open Source).
This Youtube Mashup Turns Youtube Into A First-Year MTV Tribute : No Advertisements Music 24/7 Playing Music Videos. The Source Code is available from github here and is GPL'd: https://github.com/riseofthethorax/chann3lz.