converting 25P to 50P

[vladdo]

Hello I would like ask i am converting UHD video to 50P because 25P is not smooth when fast motion.
But after converting, there are some errors, mainly tinny objects like trees,..look in attachement.
I have this script:
Cores=4
SetMemoryMax(512)
SetMTMode(3,4)
PluginPath = "C:\Program Files (x86)\MeGUI\tools\avisynth_plugin"
LoadPlugin(PluginPath+"svpflow1.dll")
LoadPlugin(PluginPath+"svpflow2.dll")
Import(PluginPath+"InterFrame2.avsi")
<input>.ConvertToYV12()
SetMTMode(2)
<deinterlace>
<crop>
<denoise>
<resize>
InterFrame(Cores=4, GPU=true, Tuning="Smooth")

Also without smooth tunnig, same result. Could by a problem with swpflow.dll files?
Simillar problem is when i play with converting in SVP 4.
Thanks
Vlado

[kuchikirukia]

I don't feel like looking at the video, but if it's some major video artifact it might have something to do with you trying to multithread multiple times. If Interframe is internally multithreaded (cores=4), try taking out the setmtmodes. Multithreaded avisynth is always a crapshoot.
If it's just bad interpolation, well that's interpolation for you.

[littlepox]

Think about this, if you can interpolate a video into double frame-rate without any visual artefacts and still keeping every motion natural, why would we need 48fps films? why would we even need 24fps film? Can't we just cut the frame-rate infinitely low and interpolate it back?

The answer is, SVP is not perfect, nor any other frame doubling algorithms. You pay for the smoothness with visual artefacts. If you don't like them, simply disable it and let the player repeat the frames for you.

[vladdo]

kuchikirukia:
I did, simillar result.Probably littlepox has right. But how can I play UHD video without grabbing, ripping (I don't know this word in english) in fast motion?
Allmost video cameras(I have Panasonic HCVX980) have only 25P,max. 29P. Only expensive profesional have 50P... Do I need swith to Full HD, where I have 50P?:angry:

[vladdo]

Everybody capture 4K video in 25 or 29P?Are you satisfied with fast motion?I think 25 or 29 P is unusable for sports scenes:confused:

[smok3]

vladdo; you are talking about your own footage recorded with your camera? If so, how do you control time of exposure?
https://en.wikipedia.org/wiki/Exposure_%28photography%29
Does shorter vs longer time makes any difference and what did you test so far? And finaly, yes 25p is generally a problem for fast motion scenes, fast pans, etc.

[benwaggoner]

In general, I've never seen a motion interpolation algorithm outside of videoconferencing that didn't make me want to rip my eyes out of my head. Some of the advanced Optical Flow stuff seems promising, but too computationally expensive for real-time, and maybe even for reasonable offline encoding speeds.

[vladdo]

But when motion or panning is not so fast, it is quite good.
What plugin is responsibile for encoding?Interframe2.avsi, svpflow1 or 2.dll?
Maybe if I update some of them could be fewer errors.

[johnmeyer]

vladdo,

What you are seeing is how motion estimation fails. It will fail whether you use MVTools2, the GPU versions of MVTools2 (SVP), the front end to SVP (Interframe) or any of the professional tools, like After Effects, Twixtor, etc.

One of the toughtest things for motion estimation to do well is video where the camera pans horizontally across crisply-defined vertical objects. The radio tower in front of the building in your still image is exactly the sort of thing I would expect to see fail.

The "ultimate" torture test is a fast pan across a picket fence.

However, sometimes you can make improvements. Changing to a different version of SVPFlow won't help, but the plugin settings you use can change your results substantially. The two settings you should try tweaking are block size and block overlap. I haven't used Interframe for a long time, so I forget exactly how to do that (actually, since it is a "dumbed down" front end to SVP, I don't think it provides those controls), but here is a script I posted a few months ago, using MVTools2 directly which, on the test clip provided, seemed to do as good a job as anyone else's attempts:

Simple slow motion, using interpolation (https://forum.doom9.org/showpost.php?p=1788725&postcount=18)

[Sharc]

vladdo
If temporal resolution is crucial, you could perhaps record your video interlaced@50 fields per second if your camera supports interlaced, and afterwards use a good bobber to convert to 50p.