Avisynth sharpening filters in Hybrid for vhs capture?

[Sharc]

The chroma is not being realigned before sharpen on these samples. Chroma must be addressed before deinterlace.

Totally agree. For PAL one can almost routinely shift the chroma 2 lines up. In Avisynth use

ChromashiftSP(x,y)

or for interlaced stuff something like

MergeChroma(Crop(0,2,0,0).AddBorders(0,0,0,2))

[Leanoric]

The chroma is not being realigned before sharpen on these samples. Chroma must be addressed before deinterlace.

Totally agree. For PAL one can almost routinely shift the chroma 2 lines up. In Avisynth use

ChromashiftSP(x,y)

or for interlaced stuff something like

MergeChroma(Crop(0,2,0,0).AddBorders(0,0,0,2))

How do I shift the chroma up for interlaced video such as the go fishing clip in this thread?


[Attachment 76859 - Click to enlarge]

[Alwyn]

For PAL one can almost routinely shift the chroma 2 lines up.

The first I've heard of that. The only time I have ever heard of Chromashift was when I asked the forum last year for a 64-bit replacement for the FlaxenVHS filter when I had to move some bad red bleeding to the left.

Chromashift has not appeared in any of the "general scripts that have been given here since I've been on the board.

That said, how does one actually determine when you need to apply it?

@Leanoric, beware, the rocket scientists that invented the CromashiftSP filter decided that right would be -X, yes minus X. At least they got the Ys going the right way: + being up and - being down, as per the wiki.

[Leanoric]

Lordsmurf said the chroma needs to be addressed before deinterlacing, but chromashiftsp accepts progressive input only?

So chromashiftsp should only be used for video that isnt getting deinterlaced?

[Alwyn]

I'm speaking out my rear end here as I gave up on Hybrid, but does Hybrid run QTGMC first? In that case, you'll have Progressive for the subsequent filters.

[Sharc]

For PAL one can almost routinely shift the chroma 2 lines up.

The first I've heard of that.

You should find discussions in this forum and/or doom9 I think. Probably a couple of years back, before the HD age.

That said, how does one actually determine when you need to apply it?

Separate the fields. Zoom into the picture and you will see the chroma displacement along edges and tiny lines. Denoise and sharpen the chroma.
You can also see the displacement along edges of deinterlaced pictures. It looks sometimes like halos on one side and fuzzy/smeared edges on the opposite side of an object.

Chroma "displacements" can also happen due to flawed YV12 (4:2:0) interlaced processing e.g. by GUIs and even NLEs as noted in the other thread.

Keep an eye on it.

[Alwyn]

Zoom into the picture and you will see the chroma displacement along edges and tiny lines.

What program are you using to zoom in? All the edges on Leanoric's fisherman video are so fuzzy there "ain't no way" I can see pixel-level chroma displacement on the edges.

What ChromashiftSP numbers would you suggest for it?

In any case, ChromashiftSP only works with Progressive. How does what you suggest (and it appears, Lordsmurf) fit into the Hybrid workflow?

[Sharc]

In Hybrid you can insert custom filters, change the filter order etc.
It's like the brightness pumping of S-video outputs of certain Pannys, crosstalk in cables, loss of details in superbrights an superdarks, banding artifacts of fast vs slower encoder settings: When you are not aware that it exists you may not see it or just live with it. And not everyone likes the idea of redoing all his tapes because he might have missed something ....

[Alwyn]

Understood.

How are you zooming in to view the edges?

What are your setting suggestions for ChromashiftSP?

[Sharc]

Understood.

How are you zooming in to view the edges?

What are your setting suggestions for ChromashiftSP?

Use AvsPmod for example.
I am sure you find the way with fiddling. If no findings, let it alone.

[Bogilein]

For PAL one can almost routinely shift the chroma 2 lines up.

The first I've heard of that. The only time I have ever heard of Chromashift was when I asked the forum last year for a 64-bit replacement for the FlaxenVHS filter when I had to move some bad red bleeding to the left.

Chromashift has not appeared in any of the "general scripts that have been given here since I've been on the board.

That said, how does one actually determine when you need to apply it?
.

Yes, chroma (color) shift is not always easy to detect. How high it is depends on the recording & playing (S)VHS recorder and the number of copies of the recording. Theoretically I think the chroma shift should move 2 pixels to the right and down with each copy, at least with PAL devices.

The chroma shift can be corrected in Avisynth or Virtual Dub.

Or even during recording with an external TBC if this is supported.

Here is the description from the instructions for an external TBC:
"When a video is copied several times a tiresome fading of the colours compared with the brightness is noticeable. This is because the PAL system shifts the colours (but only the colours) one line down and somewhat to the right. The colour shift function can shift the colours - seperately from the brightness - upwards and to the the left or right."

I usually correct the chroma shift when creating my working copy in one step at the same time as I cut out the unnecessary parts such as the beginning, end and commercials using the chroma shift filter from JPDSR in Virtual Dub which works in the YUV color space.

https://github.com/jpsdr/Filtres_JPSDR

[lollo]

A comparison between the original source and a version with chroma shifted 2 pixels up. You tell me who is good and who is not (I know the answer).



with image slider: https://imgsli.com/MjM4Nzc0

here the script I wrote to shift chroma for interlaced source (let me know if you see any error):

video_org=FFmpegSource2("tmp\Go Fishing 2.avi")

# separate fields tff
video_org_sep_tff=video_org.AssumeTFF().separateFields()

# parameters
v_shift=2

# shift chroma up
video_org_sep_tff_chroma_shift=MergeChroma(video_org_sep_tff,crop(video_org_sep_tff,0,v_shift,0,0).addborders(0,0,0,v_shift))

# shift chroma down
#video_org_sep_tff_chroma_shift=MergeChroma(video_org_sep_tff,crop(video_org_sep_tff,0,0,0,-v_shift).addborders(0,v_shift,0,0))

video_rep=video_org_sep_tff_chroma_shift.Weave()

return(video_rep)

[Alwyn]

@Leanoric really is after values for Hybrid.

As far as I am concerned, in this case, looking at ChromashiftSP, FlaxenVHS and Lollo's, there's no point in adjusting the colours. What you gain on one side you lose on the other. The tops of the trees verses the waterline, for example.

[lordsmurf]

What you gain on one side you lose on the other.

Rarely.
Usually the after/fixed version is noticeably superior.

cNR after shift, too!

[rgr]

@RGR, what Deinterlacer/ing did you use for your video in post #21 ("Go Fishing 2 (deinterlaced + denoised + sharpened).avi").

QTGMC, preset slower. Possibly with TR2=3, but I'm not sure.

[Alwyn]

Thanks.

[lollo]

As far as I am concerned, in this case, looking at ChromashiftSP, FlaxenVHS and Lollo's, there's no point in adjusting the colours. What you gain on one side you lose on the other. The tops of the trees verses the waterline, for example.

yes

What you gain on one side you lose on the other.

Rarely.
Usually the after/fixed version is noticeably superior.

Rarely what? You specifically wrote in post #27 that this video needs chroma shift. If you have no time (3 minutes in this case) to provide facts (but you spend hours to write looooong posts about TBCs) then better say nothing.
Yes, I am your friend

cNR after shift, too!

Chroma noise reduction has nothing to do with chroma shift.

[lollo]

Off topic

You all know that I think "There is nothing Topaz VEAI can do that cannot be matched/beaten by AviSynth/VapourSynth" as well as "A combination of AviSynth//VapourSynth and Topaz VEAI as upscaler or sharpener can produce sometimes excellent results", as we discussed in the famous thread https://forum.videohelp.com/threads/399360-so-where-s-all-the-Topaz-Video-Enhance-AI-discussion with @JoelHruska (if my friend lordsmurf says differently, just ignore him).

This is one example, as shown by @rgr. Thanks to him for his contribution.

I repeated the experiment, using the following AviSynth script:

AssumeTFF()
QTGMC(preset="slow", matchpreset="slow", matchpreset2="slow", sourcematch=3, tr1=2, tr2=1, NoiseTR=2, sharpness=0.1)
TemporalDegrain2(degrainTR=3)
# no sharpening

and then a simple TOPAZ VEAI (amq model); the result is nice (some over-sharpening, maybe).

On the left the result of the above script + Topaz VEAI, on the right the result of above script with the addition of LSFmod(defaults="slow"), so basically is a comparison between LSFmod and Topaz VEAI

video comparison:
comp_last.avi

image comparison:


image slider comparison https://imgsli.com/MjM4ODUw

P.S. #1: this is not a comparison between AviSynth/VapourSynth and Topaz VEAI; to do that, the first workflow should use some of the available tecniques for image improvement (VSGAN and all the others). I used AviSynth just as preparatory step for Topaz VEAI.

P.S. #2: it is clear that the final judgement depends on personal taste; some may prefere a blurred image rather than a "visually better" image where the additional details have been recreated, and could be false, or non existent, or existing in a different shape in the real world. But the pleasure of the "watching" is there.

[Selur]

@lollo: if the intension was to show that Topaz VEAI can help, then you should have removed around 90% of that post,....

[lollo]

Yes, I know.

It can help, sometimes, in combination with AVS/VS

[Leanoric]

I usually correct the chroma shift when creating my working copy in one step at the same time as I cut out the unnecessary parts such as the beginning, end and commercials using the chroma shift filter from JPDSR in Virtual Dub which works in the YUV color space.

https://github.com/jpsdr/Filtres_JPSDR

Sorry if I'm being stupid here but I cant work out how to download the chromashift filter.


[Attachment 76906 - Click to enlarge]

[Alwyn]

@Leanoric, you're not the only one! QED though; go here:

https://github.com/jpsdr/Filtres_JPSDR/releases/tag/20221120

Download and unzip that 7z file. You'll see a set of folders for x86 and x64; in there is the VDF file with all the filters which will appear in the VDub filters list when you drop it into your plugins folder and start VDub.

I'm using W11 64 so I chose the W7_AVX2 folder.

Drop the resulting file into your Plugins folder.

The single file contains all the individual plugins, which includes Chromashift. It's actually a very nice filter and works in a similar fashion to Flaxen.

[Bogilein]

https://github.com/jpsdr/Filtres_JPSDR/releases

under assets download:

filtres_JPSDR_20221120.7z file

unzip this file and copy from the x86 or x64 folder, depends on whether 32bit or 64bit version of virtual dub is used:

Filtres_JPSDR.vdf

into the plugins folder from Virtual Dub

I see Alwyn was faster with his answer...

[Leanoric]

Thanks

[Leanoric]

I cant get the filters to show up in vdub.

Like Alwyn Im using win11 64, so I chose the W7_AVX2 folder.

Ive copied the vdf file into the plugin folder but it doesnt show up in filters. Ive tried it for both vdub and vdub2. Ive also tried a couple of the other ones but none of them show up in filters when I open vdub.

Im not sure how you can tell what those different versions are, is there another one that I should try?

[Alwyn]

Attached is the "Filtres_JPSDR.vdf" I'm using (I had to rename it to ZIP because the forum doesn't accept VDFs as attachments...Baldrick?).

I have put it into my VDub2 Plugins64 folder. Once you've downloaded it, just change the file extension to VDF.

Here it is in my plugins64 folder, and you can see the various JPSDR filters scattered through the overall list.


[Attachment 76915 - Click to enlarge]

Added: looking at your plugins folder, you should have more VDFs in it. Compare it with mine; perhaps do a search for the MPEG264 (which was in the folder when I set up my copy of Vdub2) to find the correct plugins64 folder.

[Leanoric]

That pic of the empty folder was vdub1, Ive just added your file to the plugins folder for vdub2 and still nothing

[Selur]

Since I was testing my current dev version, here's an example not using Avisynth, but Vapoursynth and some ml based filters (terribly slow, eating 10GB VRAM and output is flickering).
script: https://pastebin.com/EuJsjABb
image compare:
(video attached)

Cu Selur

[lollo]

Well done, Selur!

This is then a comparison between a full AviSynth/VapourSynth processing (yours) and Topaz VEAI (helped by AviSynth) as in my previous attempt.

The winner is evident (just look to the eyes, even if the background is more "defined" in Topaz)

https://imgsli.com/MjM5MTU3

BTW, it would be nice if you could try some advanced image enhacer we discussed on doom9's forums, this sample seems to be a nice candidate for video enhacement...

[Alwyn]

still nothing

That's weird! You are running the 64bit EXE file? Check Help>About. The 64bit version is identified by "Compiled with MS Visual Studio 2008 for AMD64" in the blurb.