I'm not sure if I'm in the right section, but I thought I'd give it a shot.
I am going to be shooting a timelapse video of a skyline, and on playback I wanted to manipulate the building lights to move with the beat of the song. Think an equalizer. Later in the video I wanted the lights to form people moving. For the latter part I thought maybe shooting people in front of a green screen, and then superimposing them as the building lights? I have no idea how I'd do the superimposing, though.
I've never tried something like this, and was hoping someone could point me in the right direction. Thank you!