vhs with vertical lines

[spiritgumm]

Bought an interlaced retail VHS (which the seller conveniently included a dvd copy of). Their dvd looks pretty good, but I thought I could do better. When I play the tape, I started to see alot of fine vertical lines which arent on the seller's dvd. If I playback a scene, the lines arent always in there, so I suspect it's my VCR generating them. The tape doesnt appear to have any macrovision (I can copy it without that problem). My power cords aren't overlapping the composite cables too much; not any more than previously. Here's a sample of my own dvd recording, showing the lines. Sometimes they were just at the bottom, but it's pretty bad here. Wondering what's causing it. game.m2v

[jagabo]

You have severe chroma/luma crosstalk. Chroma is spilling over into the luma channel leading to severe dot crawl artifacts. Notice how only the areas of color have the dots, gray areas don't. Your DVD recorder isn't properly separating the composite luma/chroma signal it's getting from the VHS deck. What equipment are you using? Are there any composite/s-video switches anywhere?

[spiritgumm]

This is how the video looks with the VCR hooked straight to the TV - so it's not being caused by my dvd recorder. Are you saying a dvd recorder should clean up what you identified? Did you notice the vertical lines?
Using a Panny VCR and Panny dvd recorder DMR-ES15.

[edDV]

This is how the video looks with the VCR hooked straight to the TV - so it's not being caused by my dvd recorder. Are you saying a dvd recorder should clean up what you identified? Did you notice the vertical lines?
Using a Panny VCR and Panny dvd recorder DMR-ES15.

So do you have the VCR connected with composite (Yellow) ? Is the recorder set for composite input?

[spiritgumm]

I usually leave VCR composite cables hooked up to the dvd recorder. When I was trying to figure this out, I bypassed the dvd recorder, and hooked the TV composite (yellow) cable directly to TV.
The dvd recorder is always set for composite input, but as I said, it's only recording what it's seeing from the VCR. The video clip is what the VCR-to-TV would probably look like (I say probably because the lines appear inconsistently, as I described in OP).
Everything points to the VCR (or connection coming from it) being the culprit. The seller's dvd copy looked the same except for the lines. Maybe they used a SVHS -VCR outputting to their Funai dvd recorder (yeah, Funai).
I thought the dot crawl was from the interlaced VHS.

[edDV]

This is how the video looks with the VCR hooked straight to the TV - so it's not being caused by my dvd recorder. Are you saying a dvd recorder should clean up what you identified? Did you notice the vertical lines?
Using a Panny VCR and Panny dvd recorder DMR-ES15.

Connections appear correct.

Try a different VCR to TV.

[spiritgumm]

Alas, this is (or had been) my last good VCR... I guess I could contact the seller and ask them what equipment they used.

[jagabo]

You can get rid of most of the artifacts in AviSynth with:

BilinearResize(360,480)
BiCubicResize(720,480)

There will be a very small loss of sharpness.

[spiritgumm]

Thanks, jagabo. I remember you showed me that resizing trick with some PAL dvds I was converting to Ntsc, though I hadn't thought of it in this case. I'm not sure my own recording would be much of an improvement over the seller's copy, given the VHS source. If I were to use your suggestion, I would first re-record from the tape with the dvd recorder black level on darker. I had it on "lighter" and it looks abit washed out (the Panny black level has two settings - lighter or darker - it doesnt have an "as is" setting).
I'm really more concerned with why my VCR output was creating those lines. I'll have to get a VHS from a library to compare.

[spiritgumm]

another vertical line video, attached

[jagabo]

The same resize pair worked for that sample too. You can use BicubicResize() for both to get slightly sharper results. Even follow up with a horizontal sharpen to restore a bit more sharpness.

Mpeg2Source("spell.d2v", CPU2="ooooxx", Info=3) 
BicubicResize(width/2,height)
BicubicResize(width*2,height)
TFM(d2v="spell.d2v")
TDecimate()
# some noise reduction here will here
Sharpen(0.3,0.0)

Only the moon shot had the vertical noise. You might limit the resizing trick to that shot.

[spiritgumm]

the vertical lines happen thruout the movie (not just the 11 second clip) and I get horizontal lines after I used the resize filters in post #8. Can you suggest any other filtering to fix it?

[jagabo]

The only horizontal lines I saw were from time base errors in the source, automatic gain control differences between fields, and DCT compression artifacts. All the usual noise filters would apply. Maybe something like:

Mpeg2Source("spell.d2v", CPU2="ooooxx", Info=3) 
src=TFM(d2v="spell.d2v").TDecimate()
BicubicResize(width/2,height)
TFM(d2v="spell.d2v")
TDecimate()
RemoveSpotsMC()
VInverse() # blur some horizontal lines
McTemporalDenoise(settings="low") # general noise reduction
aWarpSharp(depth=5) # sharpen, straighten some edges
nnedi3_rpow2(2, cshift="Spline64Resize", fwidth=width*2, fheight=height) # restore width
Sharpen(0.5, 0.3) # a little overall sharpening

[spiritgumm]

horizontal lines isnt really accurate since it's not completely across the screen - it's the edges of things, so more like combing? I attached a clip from the version I made (with the post #8 filters). I tried to find a scene which will make it more apparent, but it's more noticeable on a HDTV.

[jagabo]

Yes, those are time base errors from the video tape. The best way to get rid of them is to use a line time base corrector between the VHS deck and the capture device. You can also downsize/upsize but on the vertical axis, follow with a vertical sharpen. But since your source is relatively sharp on the vertical axis you will lose some sharpeness. I used vinverse() to reduce them followed by several sharpening techniques. That gets rid of the combing but still leaves you with wiggly lines.

https://forum.videohelp.com/threads/319420-Who-uses-a-DVD-recorder-as-a-line-TBC-and-wh...=1#post1983288
https://forum.videohelp.com/threads/306272-Computer-video-capture-vs-vcr-to-dvd-combo?p...=1#post1882662
https://forum.videohelp.com/threads/230650-Confused-Why-a-VCR-with-TBC-if-separate-TBC-needed-anyway

[spiritgumm]

the good news is the horizontal edges are definitely lessened. But I can sort of notice the vertical lines, which are quite prominent if I pause the video like they're in every other frame. I didnt follow your script exactly - I omitted RemoveSpotsMC and McTemporalDenoise.
I mistakenly used BilinearResize(360,480) from the older recommendation instead of Bicubicresize; would that have been a mistake?
Btw, my dvd recorder is a Panny DMR ES15. I'm pretty sure I had to use a copyguard remover box with this vhs tape (which I no longer have).

[jagabo]

the good news is the horizontal edges are definitely lessened. But I can sort of notice the vertical lines, which are quite prominent if I pause the video like they're in every other frame. I didnt follow your script exactly - I omitted RemoveSpotsMC and McTemporalDenoise.

Yes, the downsize upsize pair left a little of the veritical lines. The later MCTD removed most of it.

I mistakenly used BilinearResize(360,480) from the older recommendation instead of Bicubicresize; would that have been a mistake?

Either will do. Bicubic will be a little sharper but will leave a little more of the vertical lines. You can try even lower resolution for the intermediate but the picture will get less sharp.

Btw, my dvd recorder is a Panny DMR ES15. I'm pretty sure I had to use a copyguard remover box with this vhs tape (which I no longer have).

The ES15 has a good line TBC. I would have expected it to work better on your tapes. Make sure you use the composite input on the back. I think the one on the front doesn't use the lTBC.

[spiritgumm]

So it sounds like I should have used the denoiser. I got tired of hunting down the dll for each error message.
I always use the back connections on the Pany. I bought the unit when it was first released.
Thank you for all the research and work!

[jagabo]

Here's what I got with the script in post 13. Original on the left (reencoded) and processed on the right.

[spiritgumm]

looks good. I tried running my abridged version of your script but it will take too long, so I was re-examining yours in post #13. I didnt use the "src" line - I only added TFM/Tdecimate and I think they should have come before the resizing filters. Is "src" a variable name used by the avsi? It looks like the TFM/TDecimate commands are called twice:

src=TFM(d2v="spell.d2v").TDecimate()
BicubicResize(width/2,height)
TFM(d2v="spell.d2v")
TDecimate()
etc

Here's my script:
MPEG2Source("D:\dvds\spell\VTS_01_1.d2v", cpu=0)
BilinearResize(360,480)
BiCubicResize(720,480)
TFM().TDecimate()
crop(6,0,-6,-8).addborders(6,0,6,8)
VInverse() # blur some horizontal lines
McTemporalDenoise(settings="low")
aWarpSharp(depth=5) # sharpen, straighten some edges
Sharpen(0.5, 0.3) # a little overall sharpening

[jagabo]

Oh, I forgot to remove the src= line in that script. I was using it to compare results with and without filtering at the end of the script with StackHorizontal(src,last).

[spiritgumm]

any idea why my version runs so slow? Does it matter that I have field matching after resizing (which I would change now)?

[jagabo]

MCTemporalDenoise() is very slow. If you have a multicore computer you can try running a multithreaded build of AviSynth to speed it up. Some people have crash/die problems with that so it's safer just to wait.

Since you're not resizing vertically resizing before field matching is ok.

[Brad]

The ES15 has a good line TBC. I would have expected it to work better on your tapes.

The "copyguard remover box" probably prevented that, yeah?

[spiritgumm]

as the 2nd video above apparently had Time Base errors, I tried the solutions suggested on a 3rd problem video (attached here), but they didnt help at all. I searched for TBC solutions but didnt find anything helpful; someone has posted a TBC script but I wasnt able to run it. The wiggles get more prominent after deinterlacing or decimating. I only have this dvdr, and cannot improve on the source for it which I never had.

[jagabo]

The software TBC filters only work when there are nice black borders at both the right and left edges and bright picture in between.

[spiritgumm]

thanks for the fast reply. I dont recall if I cropped (I definitely didnt add new borders) before trying all the suggestions above. Would cropping and re-bordering suffice before calling TBC filters?
Have you had any experience with the so-called TBC script?

[jagabo]

Would cropping and re-bordering suffice before calling TBC filters?

No. Software TBCs work by locating the start and end of each scanline (the transition from black border to non-black picture) then scaling it to the standard length and aligning the left edge. That means the tbc wiggles have to be present at the borders. For example, say a 720 pixel line starts with 4 black pixels, then the bright picture starts. The picture continues until the last 5 pixels which are black. The tbc filter resizes the 711 pixels between the black borders to 704 pixels, then adds 8 pixels to each end. The result is a standard 704 pixel line with 8 pixels of black at each end. In theory, after you've done this with all the scan lines the time base jitter is removed.

If you crop the frame and add new black borders the location of the original borders is gone. The time base filter will simply see your perfect black borders and do nothing (in the best case).

Have you had any experience with the so-called TBC script?

Yes. Even when the video matched the above criteria they would often make mistakes that made many lines worse than they started out.

[Betelman]

Jagabo,

This trick worked wonders for my video, where I was having the same trouble in some of my frames. It significantly lowered some vertical lines. However, you can still make out a wee bit of it. So I stacked the resize in my script as follows:

BilinearResize(360,480)
BiCubicResize(720,480)
BilinearResize(360,480)
BiCubicResize(720,480)

Now, aside from loss of sharpness, I don't see any other issue with my clip. My question is, is this something commonly done? Am I doing some kind of damage to my clip that I'm not aware of when I stack like this?

[jagabo]

Rather than repeating the sequence you might get better results using the downscale/upscale once but using a smaller size for the downscale. Instead of 360, try 320, or 280 -- the largest value that still eliminates the noise. And with such a small intermediate resolution a sharper downscale/upscale may work better:

Spline36Resize(280,480)
Spline36Resize(720,480)

And using nnedi3 to upscale will give even better results. The video must be progressive for that though:

Spline36Resize(280,480)
QTGMC()
nnedi3_rpow2(4, cshift="Spline36Resize", fwidth=720, fheight=480)