Smooth Slo-Mo with HV20 souce

[racer-x]

I posted this clip with fluid slow-motion at various speeds. I used Avisynth with MVtools to slow it down in stages all the way down to 1/16 speed. I also included a variable speed ramp at the end, that I made with Vegas Velocity Envelopes on the 8x slo-mo. Here is my clip:
http://www.vimeo.com/794158

We are having a challenge over at HV20.com about what S/W can create the best fluid slow-mo effect. If you'd like to participate go here:
http://www.hv20.com/showthread.php?t=8459

[Soopafresh]

Looks really great! I hope you post your script

[racer-x]

Sure, I'll post the script I used for 1/4 speed. You'll need to download the MVtools plugin. Get it here:
http://avisynth.org/warpenterprises/

Put the mvtools.dll into the Avisynth Plugins folder. Then you can use a script like this, substitute for your favorite BOB Deinterlacer. Load up the m2t in DGindex and create a project .d2v.

MPEG2Source("HDV50i_source.d2v", cpu=0)
AssumeTFF.Bob(b=0.33, c=0.33, height=720)
LanczosResize(1280,720)
smoothfps(100) # (This is how many frames you want to create)
assumefps(24) # (This is the play back framerate)
function smoothfps(clip source, float fps) {
fp=fps*100
backward_vec = source.MVAnalyse(isb = true, truemotion=true, pel=2, idx=1)
# we use explicit idx for more fast processing
forward_vec = source.MVAnalyse(isb = false, truemotion=true, pel=2, idx=1)
cropped = source.crop(4,4,-4,-4) # by half of block size 8
backward_vec2 = cropped.MVAnalyse(isb = true, truemotion=true, pel=2, idx=2)
forward_vec2 = cropped.MVAnalyse(isb = false, truemotion=true, pel=2, idx=2)
return source.MVFlowFps2(backward_vec,forward_vec,backward_vec2,forward_vec2,num=int(fp),den=100, idx=1,idx2=2)
}

[Soopafresh]

Hey, I tried it out on some footage. Works nicely. It's cool the movement doesn't turn into jello - everything still retains it's form. Thanks so much. Which parameters do you tweak to get 1/2 and 1/8 speeds ?

[racer-x]

This might help:

[2Bdecided]

The "disconnected" images in the source (due to the fast shutter speed) make it a challenge for MVAnalyse to track the motion. It can't "join" the movement of the water between frames. A longer shutter speed would create more blur, but allow better motion estimation. Pick your poison.

Yadif would be better than bob.

Cheers,
David.

[sksavis]

It looks like this script

http://nerds-central.blogspot.com/2007/04/synthetic-slow-motion-with-avisynth.html

I've tested a lot of programs, this one says they are the best

http://compression.ru/video/frame_rate_conversion/index_en_msu.html

but it gives more artifacts than your script, for a ping pong game you really see the ball disappearing and appearing elsewhere, I've also tested black-box-programs like the ones from goodervideo etc, but this one is better, theoretically it could be improved I would say although I don't know much about the avisynth scripts.

[Soopafresh]

Mvtools is better than the MSU Frame rate conversion tool. If you're unfamiliar with Avisynth, just cut and paste existing scripts until they work for you.