Revert Nearest-neighbor 'upscale' / strange aliasing

[DReffects]

Hello there!

I am trying to restore a scene that has some kind of aliasing I would describe as 'upscaling with Nearest-neighbor gone bad' type of aliasing.

Please take a look at this still:

and the very next frame:


the little steppy-steps sort of move through the frame.
It is present within the while video, which has 640x480 to begin with.

I've tried anti-aliasing with a bunch of tools, also including avisynth santiag() but had no luck.

Any Idea on how to revert this?

Thanks!

[jagabo]

It looks like the video was poorly deinterlaced. And maybe poorly scaled too. You should upload a short unprocessed, not re-encoded, sample for proper analysis.

[DReffects]

It looks like the video was poorly deinterlaced. And maybe poorly scaled too. You should upload a short unprocessed, not re-encoded, sample for proper analysis.

Ah, interesting! That never crossed my mind

I have attached an unprocessed sample for you good Sir/Madam.
You can notice the aliasing in the hair of the blonde lady as well in this short excerpt

I've also noticed the file has 29.976 fps while running TFM(), tdecimate() will return it to 23,976 frames.

[Selur]

qtgmc mode=2 or mode=3 and incresing TR0-2 should help

[DReffects]

qtgmc mode=2 or mode=3 and incresing TR0-2 should help

Thank you! I am currently experimenting with

video=QTGMC(video,Preset="Slow",FPSDivisor=2,ShutterBlur=3, TR2=3, EdiThreads=8)

this impoves it quite alot but does not completely remove the artifacts.

Which mode-setting do you mean? I was unable to find a paramater "mode" in the documentation.

[Selur]

Sorry, mode => InputType
(completely removing the effect might not be possible)

[jagabo]

You won't find any perfect fix. Try something like:

LWLibavVideoSource("aliasing.mkv") 
TDecimate(Cycle=5, CycleR=1)
QTGMC(InputType=2)

[jagabo]

Adding Santiag(strh=2, strv=2, nns=4) between TDecimate and QTGMC reduces the twitter a bit more but blurs a bit.

[DReffects]

Ah, I see! Thanks!

Vielen Dank, der Herr! Das war sehr hilfreich!

video=QTGMC(video,Preset="placebo",InputType=3, ProgSADMask=0.0,TR2=3

returns a rather decent result. It's not gone completely but really useable. <3


THANK YOU ALL for your valuable Input!