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[HELP] Unstable Umatic capture - Printable Version

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Unstable Umatic capture - Miranda - 17.05.2024

Is there anything I can do to fix this? Its from a 1983 PAL Umatic master.

sample clip


RE: Unstable Umatic capture - Selur - 17.05.2024

Looks like extrem skew error.
Aside from writing a custom script similar to ReduceFlicker, maybe applying ReduceFlicker 10+ times and Small_Deflicker additionally helps,... (not really, see attachment)
Hybrid has no build-in filter, really tailored for this.
Maybe someone over at https://forum.videohelp.com/forums/41-Restoration or https://www.digitalfaq.com/forum/video-restore/ can suggest a tool for this.

Cu Selur


RE: Unstable Umatic capture - Selur - 17.05.2024

LOL, I think I found something, try:
# removing flickering using ReduceFlicker
clip = core.rdfl.ReduceFlicker(clip=clip, strength=3, aggressive=1)
# removing grain using SMDegrain
clip = smdegrain.SMDegrain(input=clip, interlaced=False, dct=1)
the dct=1 in SMDegrain is what really helps. (but, yes it's slow)

attached an encode with:
# removing flickering using ReduceFlicker
clip = core.rdfl.ReduceFlicker(clip=clip, strength=3, aggressive=1)
# removing grain using SMDegrain
clip = havsfunc.SMDegrain(input=clip, tr=4, interlaced=False, dct=1)
# removing grain using SMDegrain
clip = havsfunc.SMDegrain(input=clip, tr=4, interlaced=False, dct=1)
=> so with some tinkering this might really be somewhat fixable.

Cu Selur


RE: Unstable Umatic capture - Miranda - 17.05.2024

Thanks, will this also work on an interlaced upscale?


RE: Unstable Umatic capture - Selur - 17.05.2024

Probably, but a lot slower,... dct=1 will slow stuff down a lot when the resolution increases,...
This is something that should be fixed during capturing the further you go down the line the harder it will be to fix,...


RE: Unstable Umatic capture - i4004 - 17.05.2024

on a hardware side of things, tbc is made to fix stuff like that....if you have one at hand....


RE: Unstable Umatic capture - Miranda - 18.05.2024

How do I add SMDegrain twice?


RE: Unstable Umatic capture - Selur - 18.05.2024

You use 'Filter Queue' instead of 'Filter Order' (read: [INFO] About Vapoursynth Filter Order/Queue), then go to SMDeGrain and add it. Smile
With 'Filter Queue' enabled there are '+'and '-' controls to the right of each filter. Smile (will probably move these to the front in the next release)


Cu Selur


RE: Unstable Umatic capture - zspeciman - 29.05.2024

I recall a model called vhs-deshaker, it addresses horizontal shakes  It analyzes the pure black at the left and right borders of VHS video frames it tries to align the frame itself.
Perhaps worth looking at.  

https://github.com/rsnitsch/vhs-deshaker?tab=readme-ov-file


RE: Unstable Umatic capture - Miranda - 30.05.2024

Looks interesting, any plans to add it to Hybrid I wonder?