You can find Airfoil Video Player right in the source popup in Airfoil, or you can just drag a movie file right onto Airfoil and it will start Airfoil Video Player for you. AVP uses QuickTime and Perian to play all sorts of media files, and all with perfect synchronization between audio and video. AVP cant play everything it needs to control the files, so they need to be local, not web-based. Likewise, Apples FairPlay DRM prevents playback, which means AVP cant play movies purchased from iTunes. But thanks to QuickTime and Perian, we support dozens of popular video formats. Now you can watch your favorite movie files through your nice stereo system without needing any wires from your computer. And although support is still preliminary, Airfoil Video Player can play DVDs, also perfectly synchronized.
If you pop open Activity Monitor, you might notice that Airfoil Video Player takes up a bit more RAM and CPU than your usual video player. You might also notice that when you press Play, the movie doesnt actually start to move for about two seconds. Both of these are due to how Airfoil Video Player works inside.
The AirTunes 2 protocol has some delay built in to it, and when sending to remote speakers with Airfoil 3 the audio is delayed by two seconds. AVP has QuickTime play the movie as usual, but doesnt display it to the screen. While the audio heads out to Airfoil and your remote speakers, the video gets buffered internally to AVP. Once two seconds worth of video has been buffered, AVP starts to draw them to the screen, resulting in perfect synchronization between video and audio output. This is a bit more resource intensive since AVP has to keep two seconds of video frames in memory at all times, but it turns out that on modern machines this doesnt have much of an impact. Even playing back a smooth 1080p video trailer downloaded from Apples movie trailers uses under 200MB of RAM for the buffer, and other types of video generally use much less.