Trying to Figure out this Special Effect

[dellsam34]

This music video clip is from the early 2000's, The singer is an Egyptian speaking Egyptian Arabic dialect, I know for a fact that there was no AI back then, Most of the video is reversed to show an old man getting younger, This man or the singer is perfectly lip-syncing the lyrics despite the video is going in reverse, The only way I can think of of achieving this is by reverse lip-syncing it, which requires a lot of practice to match the original soundtrack.

When I watched this over 20 years ago it blew my mind, but I could never understand how they did it, now that I have the video from YT I just want to see if I can reverse it along with the sound to see if my theory stands, Not sure if it really helps but doesn't hurt to check it out in reverse, or should I say in forward. I don't have any NLE, The question is could this be achieved using vdub or a ffmpeg script? Thanks.

[hello_hello]

I can't tell you if it proves anything but here it is backwards.
Motion is a bit jerky for a while in the beginning as your sample is jerky towards the end due to frames being repeated. I'm not sure why that is.

For the record it's easy enough to do in Avisynth if you have it installed and VirtualDub2 can open Avisynth scripts. Assuming you know the basics of Avisynth. You'd probably want to save it as an AVI containing raw video and reverse that.

http://avisynth.nl/index.php/Reverse

[dellsam34]

Thanks, It's hard to single out the vocals from other instruments but I can tell it's doable to reverse lip syncing, It just has to be close enough because all what matters is lip movement, the voice is not going to be heard because the original sound track is what's used. I'm surprised that I haven't seen such special effect in any other videos or movies, or maybe I haven't looked hard enough. But whoever came up with this idea is certainly talented.