XBMC is an award-winning free and open source (GPL) software media player and entertainment hub for digital media. It supports a lot of operating systems and has a very nice addon interface which makes it well expandable and customizable.
Based on the processing, analysis and animation algorithms present in fische, fishBMC offers a very similar feature set packed into an XBMC addon.
fishBMC is known to build and work on Linux and OS-X. You can find download links on the right side of this page. The full source code is included in both ZIPs.
fishBMC is also proposed for inclusion in a future version of XBMC.
fishBMC uses OpenGL for rendering. Porting it to DirectX and/or OpenGL ES would probably be trivial for anyone experienced with those libraries. I just don’t have enough capacity to do it (plus I don’t have a Windows machine)