If you want to use another application to play videos as lalandev suspects, then you would want to set up the player as an external application or emulator. Set up the filter to only show the file types that application can handle. Then, set the command line to call the application and "rom" like you would another emulator. Make sure the application will launch and start playing upon command line call (that might be the sticking point). If it doesn't, you will probably need to use some kind of a loader script written in AHK for example. I don't see this as a big benefit for this (and it would probably look ugly), so I'm hoping you are asking about using the codec.