Simple arbitrary slow motion?

[hazel-ra]

Is there anyone who knows of a simple method or function for arbitrary slow motion?

I've found pages such as these
http://atlas.kennesaw.edu/~dhirschl/avisynth.html#slowmo

But they have 1/2 speed slow motion, 33%, etc.

Is there a function for arbitrary slow mo? Where I could do 82% speed for example?

Also, does anyone know, when trailers or movies show a slowed down, emotional part, how much they are generally slowed down?

[Mug Funky]

in movieland it's not so much a matter of slow-mo'ing in editing, but overcranking the camera to shoot above 24fps.

favourite speeds are 30fps, 33, 50. 30 is usually used to make people look a little more graceful, and often you can't really tell it's been done (so long as there's no syncsound).

in avisynthland, you can use motionprotectedfps, or mvfps, or a couple of other things. search should reveal some nice stuff.

as far as "speed-ramping" goes, a function could be written, but i'm not aware of anyone having done that yet. would be lots of tricky maths. twixtor in after-effects or shake would be a better way to do that, as it can be keyframed in the GUI.

[Sagekilla]

Simple:

function SlowMotion(clip src, float "rate")
{
rate = default(rate, 0.5) # 1 ~ inf. Percent original speed.


fnum = src.frameratenumerator()
fden = src.frameratedenominator()
super = src.MSuper(pel=2)
bvec = super.MAnalyse(isb=true, overlap=4)
fvec = super.MAnalyse(isb=false, overlap=4)
return src.MFlowFPS(super, bvec, fvec, num=int(fnum/rate*1000), den=int(fden*1000)).assumefps(fnum, fden)
}

Needs tweaking, but that's the basic idea

[Gavino]

return ... .assumefps(fnum/fden)
}
Should be assumefps(fnum, fden)

[Comatose]

I've noticed on TV that slow/fast motion sequences are usually considerably choppier than the rest of the show. So I imagine that for 50% motion PAL, for example, they do something like this:
assumefps(framerate*0.5).changefps(framerate)

Of course like Mug Funky says I've also seen smooth slow motion which did seem to be taken a higher framerate and then slowed down to 25 fps (for PAL), but the majority is done like this. (and coincidentally, it's the easiest way :p)

[Sagekilla]

All a matter of artistic views. If you're looking for very smooth slow motion, ideally you would shoot at a higher frame rate and play it back at the same rate as everything else. I.e. if main program is 30 fps, shoot at 60 fps and playback at 30 fps.

Otherwise, if you want a choppier look you would do the same then drop frames.

[Comatose]

Or just play 30 fps at 15 fps and dupe frames.

[Mug Funky]

just to show off... this ad won ALL the awards.

shot at >1000fps, high-def on the "phantom" camera. i wish i'd worked on it...

http://www.youtube.com/watch?v=pRFfJJjLpqw

[Comatose]

i came