Basic Avisynth script errors?

S1RIUS · #1 10-16-2020, 03:01 PM

Hi everybody,

Thank you for your forum, I've read a lot about VCR and TBC since I'have started my adventure to capture VHS

I'm now using a random Sony VCR, I'm about to get a HR-7955MS (I'm based in France)
So actual "test" capture are made with my random Sony VCR to Magewell Pro HDMI using RCA.

Capturing 4:2:2 bt.601 (real-time compressed with Utvideo).

I wanted you to know if there is any "big" error in my basic script, I dont want to be too much agressive on the process part. I not sure about where to place MatrixColor and convertion to YV12.

I m getting some yellow "halo line", but its maybe the VCR ? I may need to see with the JVC.

Code:

source=AviSource("test2.avi")
ConvertToYUY2(interlaced=true, matrix="rec601")
AssumeTFF()
QTGMC(Preset="Slower", InputType=0, TR1=3,SLMode=2, Sharpness=0.5, SourceMatch=3, Lossless=2, MatchPreset="Slower", MatchPreset2="Slower")
Crop(8, 0, -8, 0)
AddBorders(8,0, 8, 0)
ColorMatrix(mode="Rec.601->Rec.709", clamp=0)
ConvertToYV12()
Lanczos4Resize(x)  # I'll maybe use different stuff to upscale.

I've attached a preview of the script running, left is yadif only, right is the script.
Full scale image : https://img.super-h.fr/images/ee1b6d...ffe172418a.png

lordsmurf · #2 10-17-2020, 02:54 AM

I'd need a sample clip to run tests -- and time, and a working UPS so I could turn my system back on.

Post that, so others can help.

Looking solely at the still clip, I see chroma noise + offset.
Fix the offset

Code:

ChromaShift()

VirtualDub CCD 1.7 works best for the noise, at probably near-default (slider 1/3rd from left) values

Colors are off. You can attempt to tackle this in Avisynth (and our color wizard sanlyn does so), but I prefer VirtualDub for something this basic (ColorMill), or Adobe Premiere for more advanced color work.

QTGMC is great, but Preset="Slower" sucks. All it does is blur.
Use Faster

Code:

Preset="Faster"

Or Medium in the atypical situation that alias/jaggy is still harsh.

Why was this done?

Code:

InputType=0, TR1=3,SLMode=2, Sharpness=0.5, SourceMatch=3, Lossless=2, MatchPreset="Slower", MatchPreset2="Slower"

That's a lot of declarations.
Sharpness is especially not great.

Also, why?

Code:

ColorMatrix(mode="Rec.601->Rec.709", clamp=0)

I never specify matrix, if not doing something for Blu-ray.

Why?

Code:

I'll maybe use different stuff to upscale

That is indeed a craptastic upscaler, but why upscale VHS at all? You'll lose quality, not gain anything. The only exception is why restoring it to HD, and none of your filter work is restoring for HD. All I see is SD corrections. As it should be.

S1RIUS · #3 10-18-2020, 08:40 AM

Quote:

Originally Posted by lordsmurf

I'd need a sample clip to run tests -- and time, and a working UPS so I could turn my system back on.

Post that, so others can help.

Looking solely at the still clip, I see chroma noise + offset.
Fix the offset

Code:

ChromaShift()

VirtualDub CCD 1.7 works best for the noise, at probably near-default (slider 1/3rd from left) values

Colors are off. You can attempt to tackle this in Avisynth (and our color wizard sanlyn does so), but I prefer VirtualDub for something this basic (ColorMill), or Adobe Premiere for more advanced color work.

QTGMC is great, but Preset="Slower" sucks. All it does is blur.
Use Faster

Code:

Preset="Faster"

Or Medium in the atypical situation that alias/jaggy is still harsh.

Why was this done?

Code:

InputType=0, TR1=3,SLMode=2, Sharpness=0.5, SourceMatch=3, Lossless=2, MatchPreset="Slower", MatchPreset2="Slower"

That's a lot of declarations.
Sharpness is especially not great.

Also, why?

Code:

ColorMatrix(mode="Rec.601->Rec.709", clamp=0)

I never specify matrix, if not doing something for Blu-ray.

Why?

Code:

I'll maybe use different stuff to upscale

That is indeed a craptastic upscaler, but why upscale VHS at all? You'll lose quality, not gain anything. The only exception is why restoring it to HD, and none of your filter work is restoring for HD. All I see is SD corrections. As it should be.

Thanks for having a look and editing title I was not able to edit more than 2 times

I see what you mean with QTGMC Slower (i use TR2 (not TR1 my mistake) to control the strength of the denoiser) but yes its too strong you are right. Using Faster is softer.

Isnt converting to bt.709, as upscaling to 1080p safer ? I because I will give the output to my family which is reading the file with a random player that I dont control the settings.

Thanks for the tip about Chroma shifting and Color, as I 'm still learning, I tested

Code:

ColorYUV(off_u=+10, off_v=0)
Histogram("levels")

I will try out ColorMill, thanks !
As far as I understand signal must be in the center.

But for Chroma shifting I have trouble seeing how to setup it. Is my Chroma too much on the left ?
See attachements, is the only way to detect shift is what I have outlined in red ?

Left is untouched, right is

Code:

ChromaShift(C=6,L=0)
ColorYUV(off_u=+10, off_v=0)

Thanks again for sharing your knowledge.

(Raw clip is : http://gofile.me/6HB3Z/u6n1OlSy5)

S1RIUS · #4 10-18-2020, 07:54 PM

Hi,

I've read the wonderful post by Sanlyn (http://www.digitalfaq.com/forum/vide...html#post58509) so I did more ChromaShifting and Color correction testing.

The Chroma Shifiting is sorted I guess (as we can see on the rear right wheel and the left tree, and the shoulder on the other sample)

But about color correction, I try to keep the signal on the center, maybe I dont know to use the histogram because the 'after' seem wrong to me. (I'm color blind)

Shoud I try to keep the peak on the perfect center of the histogram, are juste keep the signal in the bound ?

Thanks !

1.jpg

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lordsmurf · #5 10-19-2020, 05:27 AM

Which is which?
- The left looks better. The right is skewed colors. Neither is great.
- If the right is the after, then your monitor isn't calibrated. You're correcting it badly, too blue, too magenta.

Histograms are a computer seeing values. That's great and all, can be helpful, but computers are stupid. Let your eyes assist, and your eyes are the final determiner. Relying only on histograms reminds me of idiots that drive into a lake because the GPS told them so.

If your eyes are green/newbie, or you actually have eyesight issues, then seek a second opinion from one of us who uses a calibrated setup.

S1RIUS · #6 10-19-2020, 06:26 AM

Hello,

Thanks for having a look.

Left is untouched chroma / colors. Right is Chroma Shifted + color correction.

As you said its too blue / magenta, its what I feel also, I may have pushed the thing to strong trying to set the signal in the center.

For the Cat scene i'm using

Code:

ChromaShiftSP(X=-8, Y=2)
ColorYUV(off_u=10, off_v=-4)

For the tractor i'm using

Code:

ChromaShiftSP(X=-8, Y=0)
ColorYUV(off_u=4, off_v=14)

I have included a set of sample.

Thanks !

lordsmurf · #7 10-19-2020, 06:34 AM

This will mostly be a situation of trial-and-error. Are you using AvsPmod to assist?

Also...

When posting scripts, please use the CODE bbcode, which is the # symbol on the reply bar, or in "go advanced" replies.
Some scripts can be messed up by forum auto-corrections of post syntax and spacing.

codebbcode.jpg

S1RIUS · #8 10-19-2020, 08:29 AM

No, i'm just using a script to compare left/right.

S1RIUS · #9 10-21-2020, 09:01 AM

Hello again,

Random Sony RCA vs JVR HR-S7955MS S-Video (EDIT mode, B.E.S.T off, Video Stab Off, unfortunately the MS version seem to dont have TBC

)

RAW unfiltered.

comparoVCR.00.jpg

S1RIUS · #10 10-26-2020, 09:08 AM

Hi,

I'm doing comparison between a VHS that a lab captured into a DVD years ago (left) and mine (right) with the same VHS source. I have a overall better definition but also serious yellow/blue halo, and white border arround people.

Chroma shifting as been done already (-4) and chroma denoise also, vsTemporalsmoother/ccd. What kind of artefact is it ? Can this be caused by my VCR ?

ski.00.jpg