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View Full Version : Help with some serious denoiseing

mahsah
17th November 2007, 20:45
Could someone help me remove this noise from this anime clip? The noise is not very easy to see in a still frame, so I have posted a short clip here:

http://www.sendspace.com/file/vqmcs1

It is in lossless lagarith, get here: http://lags.leetcode.net/codec.html

Seriously, I am not sure where to start for denoiseing this clip, and if someone could make an avisynth script or suggest some filters and settings it would be great.
Adub
17th November 2007, 21:47
Frankly the clip you posted it is also hard to see the grain. Do you have a daylight shot? Or at least one with brighter colors? Great expanses of color, like a wall or a door would be great as well.
[P]ako
18th November 2007, 05:20
All I see it is some kind of blocking. I may suggest you to use deblock.
mahsah
18th November 2007, 05:51
It actually is more visible in areas with dark/blue lighting...

here are some better clips:

This is a good example that's a little brighter: http://www.sendspace.com/file/8uwu07

Less noticable because of the lighter colors, but you can still see it in areas of one color: http://www.sendspace.com/file/dnfehj
montython
18th November 2007, 06:54
The noise is not very easy to see in a still frame, so I have posted a short clip

My eyes cannot spot significant (if any) noise in these clips. Maybe my eyes are not sensitive enough. If you say that it is easier to see it in motion rather than in still frames, can it be a clue for noise in spatial nature?

What about trying spatial (or spatio-temporal) denoisers? FluxSmooth for example...

FluxSmoothST (7,7) is the default setting, the second number being the spatial threshold. Maybe increasing this could help?
mahsah
18th November 2007, 23:16
Alright, I think I have a good script, could someone take a quick look over it and see if there is anything that I could improve on?


Directshowsource("noise3.avi").converttoyv12
FFT3Dgpu(sigma=2,bw=64,bh=64,ow=32,oh=32,plane=4,bt=4)
vmtoon()
removegrain(mode=1)


Note that I am also using the deband filter in ffdshow on playback, which makes it look alot better.
Adub
21st November 2007, 00:24
Why not us a debanding filter in you avs script then? That way you should get a perfect encode, with no need for playback processing. Perfect output file you can take anywhere and still have it look great.
mahsah
21st November 2007, 21:21
Why not us a debanding filter in you avs script then? That way you should get a perfect encode, with no need for playback processing. Perfect output file you can take anywhere and still have it look great.

The banding is actually caused by H264 (or rather the yv12 colorspace) if I understand correctly... look in the thread for gradfun2db for more info...