Live music to video

[SentencedToBurn]

Im sure you guys here have been to plenty of shows and have seen a band play to a projected video or something to that effect. So i was wondering how is it done? the video always is synced to what they are playing in real time. So what program does that? i know they arent watching the video and playing to it.
Usually experimental electronic type bands do this but ive seen a couple metal bands do it.

 

[XnaySaturo]

I guess the band plays to a click. I know that's what Porcupine Tree does. I guess you could use any video program and have the click as the sound in the video and just play to that.

 

[arv_foh]

I synced up an hour worth of video for a band. They have their entire show programmed into Pro Tools, they just sent me the exported wav file with all the studio versions of the songs synced up to the show and I edited the video to that

 

[narcossintese]

You can program some crazy stuff on MAX for Ableton Live. Like chop a video in 12 parts equal parts and each midi note trigger a sequence with random video fx.