Still have flicker after Denoising with AviSynth

[VideoFanatic]

I seem to have a problem where after denoising I still have flicker. Some videos which are high quality don't have this problem, it just seems to happen with videos which are lower quality. Here's the script I use:

The first line deblocks and denoises. The other lines get rid of the remaining noise.

Mpeg2Source("I:\New\z = Encode\RAW July 21 1997 Edited.track_224.d2v", CPU=6)
DeGrainMedian(limitY=2, limitUV=3, mode=1, interlaced=true)
DeGrainMedian(limitY=2, limitUV=3, mode=1, interlaced=true)

Here's a sample

Here's an ISO


Could someone please suggest a script that would get rid of this flicker. Thanks

[themaster1]

Have you tried deflicker ? http://avisynth.org.ru/deflicker/deflicker.html

[VideoFanatic]

I had a look at it but I wasn't sure what script I was supposed to use

[themaster1]

send the original video sample please, i'll have a look at it

[VideoFanatic]

Here's the original where I haven't yet fixed the audio or video.

[themaster1]

It seems hard to fix

This is the best i can do for now: http://www.megaupload.com/?d=4I8RA72K

[VideoFanatic]

I kind of flashes now every few seconds which is distracting which is more annoying than the original flicker!

Apart from that, the video looks great. You seemed to have improved the picture quality and colours. What script did you use?

[poisondeathray]

@themaster1 - if you add ttempsmooth or similar temporal averaging filter , you can get rid of the luminance flicker. Ideally you would factor it into the denoising, otherwise picture becomes too soft . You can use chubbyrain2 to get rid of the color flicker at the top of the frame, or use a strong ttempsmooth (high cthresh and lthresh values) filtered overlay (also for the bottom strip if you want it more stable)

[themaster1]

msu deflicker seems to work (blend mode, default values) i have analysed with the histogram the luma fluctuation is much better sadly it don't work in avisynth (functions errors)

[poisondeathray]

if you add ttempsmooth to the filtered video you posted it will smooth out the fluctuations. IMO, it's a bit too soft (ttempsmooth denoises too), so I would have used weaker denoise settings in combination with it or some similar combination. Vdub's temporal smoother is similar to ttempsmooth, but not as good, but you can give a shot too

chubbyrain2
ttempsmooth(maxr=3, lthresh=8, cthresh=5, strength=4, interlaced=true)

if you want to smooth out the top few pixels colors fluctuating , use strong settings, with a cropped overlay to replace those pixels

[jagabo]

VirtualDub Deflicker by Donald Graft.

[themaster1]

What script did you use?

Download it here http://www.megaupload.com/?d=UQOK3BMJ

[VideoFanatic]

VirtualDub Deflicker by Donald Graft.

Does that work with AviSynth? If so, could you please give me a link to the documentation page and if possible could you please suggest a script for me to use. Thanks

[jagabo]

I used Donald Graft's DeFlicker filter for VirtualDub in VirtualDub. But you can call it from an AviSynth script:

LoadVirtualDubPlugin("path\to\deflick.vdf", "DeFlick")

Mpeg2Source("Original file Test.d2v", CPU=2)
ColorYUV(gain_y=40, off_y=-36) #fix levels
QTGMC() #deinterlace
McTemporalDenoise(settings="low") #deniose

ConvertToRGB32() #necessary for VirtualDub filters

# deflick(?, window size, ?, scene change threshold, show scene change as red)
# the two unknown parameters are interlaced and softening, I set both to 0
DeFlick(0, 12, 0, 256, 0) # the second parameter is the main deflicker control

ConvertToYV12() # output as YV12 for x264

[VideoFanatic]

if you add ttempsmooth to the filtered video you posted it will smooth out the fluctuations. IMO, it's a bit too soft (ttempsmooth denoises too), so I would have used weaker denoise settings in combination with it or some similar combination. Vdub's temporal smoother is similar to ttempsmooth, but not as good, but you can give a shot too

chubbyrain2
ttempsmooth(maxr=3, lthresh=8, cthresh=5, strength=4, interlaced=true)

I used ttempsmooth(maxr=3, lthresh=8, cthresh=5, strength=4, interlaced=true) and it got rid of the flicker. Awesome. What settings would you suggest I use if I just want to get rid of the flicker without denoising (or minimal denoising) as I already use another denoiser?

[VideoFanatic]

I used Donald Graft's DeFlicker filter for VirtualDub in VirtualDub. But you can call it from an AviSynth script:

LoadVirtualDubPlugin("path\to\deflick.vdf", "DeFlick")

Mpeg2Source("Original file Test.d2v", CPU=2)
ColorYUV(gain_y=40, off_y=-36) #fix levels
QTGMC() #deinterlace
McTemporalDenoise(settings="low") #deniose

ConvertToRGB32() #necessary for VirtualDub filters

# deflick(?, window size, ?, scene change threshold, show scene change as red)
# the two unknown parameters are interlaced and softening, I set both to 0
DeFlick(0, 12, 0, 256, 0) # the second parameter is the main deflicker control

ConvertToYV12() # output as YV12 for x264

Works perfectly, thanks. Just wondering though, should I be using this if my clip is interlaced?:

ConverttoRGB32(interlaced=true)

Also the 3rd setting of DeFlick says this: Interlaced source: If the source video clip is interlaced, check this option to enable field-mode processing. So should I set the 3rd setting to 1 to turn that setting on?

[VideoFanatic]

Tweak(Hue=0.0)

Guys, would setting the Hue like the above example have no effect if the hue was already correct?

What exactly is the purpose of the MaxSat setting? Could it be used for setting a sat setting so that if a video needs the sat fixed then it fixes it and if it doesn't then it has no effect?

Also can someone please point me to a page which shows some documentation for chubbyrain2 as I can't find one and could you please suggest a script to use for it. Thanks

[manono]

Tweak(Hue=0.0)

Guys, would setting the Hue like the above example have no effect if the hue was already correct?

It'll have no effect (except to clip the Luma and Chroma) whether the hues are correct or not.

The pictures lower down on the Tweak page explain what max and min sat do and how to use them. If you don't understand, play around with the numbers and see.

As for Chubbyrain2, try here:

http://forum.doom9.org/showthread.php?p=589885#post589885

[VideoFanatic]

Tweak(Hue=0.0)

Guys, would setting the Hue like the above example have no effect if the hue was already correct?

It'll have no effect (except to clip the Luma and Chroma) whether the hues are correct or not.

The pictures lower down on the Tweak page explain what max and min sat do and how to use them. If you don't understand, play around with the numbers and see.

As for Chubbyrain2, try here:

http://forum.doom9.org/showthread.php?p=589885#post589885

Why does the Hue setting exist if it does nothing?

Where can I download ChubbyRain as I don't see a download link anywhere. Isn't there any better documentation than on that forum page? Thanks

[Gavino]

Works perfectly, thanks. Just wondering though, should I be using this if my clip is interlaced?:

ConverttoRGB32(interlaced=true)

Also the 3rd setting of DeFlick says this: Interlaced source: If the source video clip is interlaced, check this option to enable field-mode processing. So should I set the 3rd setting to 1 to turn that setting on?

No to both questions.
At this point in the script, the source has already been deinterlaced by QTGMC, so ConvertTORGB32 and DeFlick are getting a progressive input.

Why does the Hue setting exist if it does nothing?

It's Hue=0.0 that does nothing as it's a zero adjustment - other values of Hue will adjust the hue.

[VideoFanatic]

Works perfectly, thanks. Just wondering though, should I be using this if my clip is interlaced?:

ConverttoRGB32(interlaced=true)

Also the 3rd setting of DeFlick says this: Interlaced source: If the source video clip is interlaced, check this option to enable field-mode processing. So should I set the 3rd setting to 1 to turn that setting on?

No to both questions.
At this point in the script, the source has already been deinterlaced by QTGMC, so ConvertTORGB32 and DeFlick are getting a progressive input.

I'm not using QTGMC, this is the script I'm using:

LoadVirtualDubPlugin("C:\Program Files\AviSynth 2.5\plugins\deflick.vdf","DeFlick") 
Mpeg2Source("I:\File.d2v", CPU=6)
ConverttoRGB32(interlaced=true)
DeFlick(0, 12, 1, 256, 0) 
ConvertToYV12() 
DeGrainMedian(limitY=2, limitUV=3, mode=1, interlaced=true)
DeGrainMedian(limitY=2, limitUV=3, mode=1, interlaced=true)

So would the highlighted text be correct if my clip is interlaced and I want to keep it interlaced?

[jagabo]

LoadVirtualDubPlugin("C:\Program Files\AviSynth 2.5\plugins\deflick.vdf","DeFlick") 
Mpeg2Source("I:\File.d2v", CPU=6)
ConverttoRGB32(interlaced=true)
DeFlick(0, 12, 1, 256, 0) 
ConvertToYV12() 
DeGrainMedian(limitY=2, limitUV=3, mode=1, interlaced=true)
DeGrainMedian(limitY=2, limitUV=3, mode=1, interlaced=true)

So would the highlighted text be correct if my clip is interlaced and I want to keep it interlaced?

Yes. Except I don't know what the order of the arguments to DeFlick() are. Interlaced could be the first or third argument. The others I figured out via experimentation. I wasn't able find any documentation regarding this.

By the way, the sample had no scene cuts so I set the scene cut threshold very high. On a video with scene cuts you need to use a lower value so it doesn't try to deflicker across the cut.

[manono]

Where can I download ChubbyRain as I don't see a download link anywhere. Isn't there any better documentation than on that forum page? Thanks

It's a function (not a DLL). That is Chubbyrain2. Copy and paste it into an AVS. If you make that an AVSI, it's supposed to Autoload into your script, but I generally use the Import command to bring functions into a script.

I can't tell you more than that as I've never used it myself. Maybe pdr knows. Or maybe you can play with the various parameters and figure them out for yourself. Try it at the default settings and then play with 'th' (threshold), 'radius', and 'sft' (?).

[VideoFanatic]

LoadVirtualDubPlugin("C:\Program Files\AviSynth 2.5\plugins\deflick.vdf","DeFlick") 
Mpeg2Source("I:\File.d2v", CPU=6)
ConverttoRGB32(interlaced=true)
DeFlick(0, 12, 1, 256, 0) 
ConvertToYV12() 
DeGrainMedian(limitY=2, limitUV=3, mode=1, interlaced=true)
DeGrainMedian(limitY=2, limitUV=3, mode=1, interlaced=true)

So would the highlighted text be correct if my clip is interlaced and I want to keep it interlaced?

Yes. Except I don't know what the order of the arguments to DeFlick() are. Interlaced could be the first or third argument. The others I figured out via experimentation. I wasn't able find any documentation regarding this.

By the way, the sample had no scene cuts so I set the scene cut threshold very high. On a video with scene cuts you need to use a lower value so it doesn't try to deflicker across the cut.

I downloaded the deflick script and opened the HTML help file. It says this:

The following options are available:

Window size: This is the size of the moving average of frame luminance values. This produces the luminance value that frames are adjusted to. The idea is that you want it as small as possible while still removing flicker. Ideally, it is equal to the number of frames that one flicker period spans. For example, if the video frame rate is 25 fps and the flicker is at 7 fps (example of 18 fps shot at 25 fps; 25 -18 = 7), then one flicker period is 25/7 = 3.57 frames. We want our window to exactly cover an integral number of flicker cycles. So a good choice here would be a window size of 7 (~ 2 * 3.57). You can always set a long window size if in doubt, but doing so will spread out luminance changes in the clip. A window size of 10 is a good general-purpose compromise.



Softening: This is the threshold for the final temporal softening phase. Often, the physical process that creates the flicker also creates within-frame illumination changes, causing adjacent frames to differ. This softening phase greatly reduces this effect. A higher number causes greater temporal softening but can leave motion trails. If the physical process does not produce within-frame changes, this phase can be disabled by setting the softening to 0.



Interlaced source: If the source video clip is interlaced, check this option to enable field-mode processing.


Scene change threshold: At a scene change it is desirable to reset the filtering so that sudden changes of luminance are not smoothed out by the filter. This threshold determines the sensitivity of the scene change detection. Use lower numbers for more sensitive scene change detection. Use a threshold of 256 to disable scene change detection.



Show scene changes: To help in tweaking the scene change threshold, this option when selected causes scene change frames to be replaced by completely red frames.

So would I be correct in assuming that the 3rd setting is for the interlaced source setting?

[VideoFanatic]

By the way, the sample had no scene cuts so I set the scene cut threshold very high. On a video with scene cuts you need to use a lower value so it doesn't try to deflicker across the cut.

What setting would you suggest as there are lots of scenes in a wrestling program just like in any other TV program?

Why wouldn't I want it to keep deflickering into the next scene? I don't want the flicker!

[jagabo]

So would I be correct in assuming that the 3rd setting is for the interlaced source setting?

Nowhere does it say that is the order of the arguments when passed on the command line. And it's obviously not since it lists Window Size first but it's the second argument as determined by experimentation.

By the way, the sample had no scene cuts so I set the scene cut threshold very high. On a video with scene cuts you need to use a lower value so it doesn't try to deflicker across the cut.

What setting would you suggest as there are lots of scenes in a wrestling program just like in any other TV program?

Why wouldn't I want it to keep deflickering into the next scene? I don't want the flicker!

Scene cut threshold does not stop it from deflickering the next scene. What it does is prevent the smoothing from crossing scenes. For example, if you have a dark scene followed by a light scene, you don't want the end of the dark scene to become lighter and the start of the light scene to become darker -- so that they're both the same brightness at the scene change. You want the dark frames be be deflickered only relative to the other dark frames, then for the light frames to be deflickered only relative to the other light frames.

You'll have to determine for yourself what the correct threshold is for your material. The Show Scene Change In Red option is there to help you see what it detects as a scene change.

[VideoFanatic]

I tried setting each of the settings that were on 0 to 1 to see if any of them turned on the "Show Scene Change In Red" option and I made a few videos and I didn't see any red in any of the videos. This is frustrating!

[jagabo]

I tried setting each of the settings that were on 0 to 1 to see if any of them turned on the "Show Scene Change In Red" option and I made a few videos and I didn't see any red in any of the videos. This is frustrating!

Did you look at my script? I told you the order of the options I was able to figure out.

# deflick(?, window size, ?, scene change threshold, show scene change as red)
# the two unknown parameters are interlaced and softening, I set both to 0

With the sample clip I had to set the threshold to 1 before I saw any red frames -- because there were no scene changes.

[Gavino]

The easiest way to determine the parameter order is to set up the filter in VDub, then 'Save Processing Settings' to a .vcf file.
Open that file in a text editor and you can see a line corresponding to the filter settings - use the same order when calling the filter in Avisynth.

[jagabo]

The easiest way to determine the parameter order is to set up the filter in VDub, then 'Save Processing Settings' to a .vcf file.
Open that file in a text editor and you can see a line corresponding to the filter settings - use the same order when calling the filter in Avisynth.

Thanks for that Gavino. By that method I get:

DeFlick(window size, softening, interlaced, scene change threshold, show scene change)

Which differs from what I reported earlier and matches the order in the filter's discription (posted by holygamer). I'll have to double check...

<edit>
It looks like I was wrong earlier. The order is as indicated in this post and in the filter's description. And it's Softening that is responsible for the deflickering in this clip, not Window Size. The higher you set Softening the more the video is deflickered.
</edit>