Green/pink vertical stripe on the right of a captured Video 8 AVI

[ringo1]

Hi!

I attached a screenshot of an AVI that I captured with a Sony Digital 8 camcorder from a Video 8 tape.

[Attachment 56472 - Click to enlarge]

There is a vertical stripe with falsy colors on the right of the video, about 10-12 pixels wide.

The stripe appears most obviously as a green stripe on red areas, as it does on the red jacket in the screenshot.

What is the reason for this?
And can I prevent it, e.g. by trying another camcorder (which I do not currently have)?
Or is this on tape?

[phelissimo_]

I've experienced this on my Hi8 tapes too.

[jagabo]

That's typical of Sony D8 caps of (Hi)8mm tapes.

[ringo1]

I cannot say that for sure, because my flat TV does not show the full size due to overscan and the overscan seems uncustomizable on that source.

But my guess is that the camcorder does output the stripe.

[ringo1]

jagabo, so you're saying, it is not on the tape?
So buying a fully analog camcorder is worth a try?

[jagabo]

I don't know if it's on the tape or not. But many people using Sony D8 camcorders report the same issue. Sometimes much worse than yours.

The discoloration can be fixed by smearing the color near the edge over to the edge.

[phelissimo_]

I've looked now at some of the Hi8 tapes which I captured on a D8 camcorder and they also have such a green stripe.

[dellsam34]

It's chroma shift, it's inherit to tape based analog consumer camcorders, It can be fixed after capture in the digital domain, Never done it though, I'm pretty sure some members here dealt with this problem before.

[Barrythecrab]

There is a plug-in maybe from JPDSR? collection? I’m not home to check but it’s so easy even I did it a few times.
I had boxing tapes where the colors of the ring ropes didn’t line up with the actual ropes. The whole image did but the ropes were in-your-face. I’ll find it later.

[jagabo]

It's hard to tell from the image but it doesn't look like a chroma shift to me. It's more of a loss of one of the chroma channels near the right edge of the frame. A different playback device might help. See the differences in playback by different VHS decks in this post:

https://forum.videohelp.com/threads/396561-Questions-regarding-my-VHS-C-capture-workfl...-)#post2578190

[Barrythecrab]

OK I got it.
You have to load the filter in VDub, and it's filters_JPSDR.vdf.
https://github.com/jpsdr/Filtres_JPSDR/releases
Chroma shift 2.02 is one of the filters.
Of course, it may not be what you need, we won't know until you try it.

[ringo1]

Thanks, I've tried the chroma shift, but it doesn't seem the solution!

By shifting CR by 8-10px to the right, the stripe is gone, but now the rest of the image is shifted too far, as can be seen on the OSD menu "shadow" that I marked in the screenshot:

[Attachment 56488 - Click to enlarge]

So, I guess I'll try to get a fully analog camcorder.

[themaster1]

See this thread (it's about secam purple stripes but that's the same principle):https://forum.videohelp.com/threads/385637-Erase-red-purple-mark-%28VHS-capture%29

[dellsam34]

As Jagabo mentioned, it's not chroma shift as I called it, What I see is the lines of chroma are shorter than the luma lines by few pixels, If one can writes a code to expand the chroma lines to a full length it will solve the problem I believe. Or see if Vdub has a setting for that.

[oln]

Yeah, this is an inherent thing on the newer PAL Sony Hi8/D8 camcorders (when playing PAL tapes), the last few rightmost pixels of one of the color channels end up being "blank". I've seen similar effects on one or more edges from the later Sony PAL Hi8 decks as well. (It's possible the cheapest EV-C400 didn't do it as it doesn't feature any digital processing, but the playback on the one we got is busted so can't check).

I have a small avisynth script I use that extends the chroma lines a little bit to mask it, I can post it when I find it.

If you for whatever reason really need the chroma in those last lines, the older generations of sony camcorders, and ones from hitachi don't have the issue, though the former have no TBC/DNR and I've found the TBC to be a bit unreliable on the hitachi camcorders. The playback quality is maybe a tad less good as well, and at least the older generation sonys tend to suffer from bad capacitors so it's not something I would generally suggest going for.

[jagabo]

Here I took the colors from near the edge and spread them to the right to fill in the discolored area:


[Attachment 56501 - Click to enlarge]

[ringo1]

Here I took the colors from near the edge and spread them to the right to fill in the discolored area:

Looks good! I guess you did it with photoshop or the likes?

@oln
How does the post-processed video look in motion?
Sure, I could also cover the stripe with black, losing those 10px if they look awkward anyway.

But I really consider to buy an old Sony CCD-FxxxE or something and try with this as a playback device. I've read somewhere that the playback device should be as similar as possible to the recoridng device to reach best results.

[jagabo]

Here I took the colors from near the edge and spread them to the right to fill in the discolored area:

Looks good! I guess you did it with photoshop or the likes?

No, I did it in AviSynth. The technique works with full motion video. Of course, there will be some color misalignment depending on the particular video. Unfortunately, I deleted the script and emptied the trash. I can recreate the script if you're interested.

[dellsam34]

What if the chroma lines get extended by the right amount of pixels (say 10 pixels), so they start from the same point with the luma on the left of the frame and end at the same point on the right of the frame, This will give better results than just adding a dummy strip of colors.

[jagabo]

What if the chroma lines get extended by the right amount of pixels (say 10 pixels), so they start from the same point with the luma on the left of the frame and end at the same point on the right of the frame, This will give better results than just adding a dummy strip of colors.

No, then the chroma will only be aligned with the luma at the left of the frame. It will be off by more and more as it gets the the right of the frame. And at the far right of the frame the chroma will be off by just as much as when you just stretch only the chroma near the right. So you're compromising almost the entire frame and still have the same errors at the far right.

[dellsam34]

Yes I know but it will be a transitional shift not a whole shift, Besides it could be that the chroma is shorter due to the exact opposite shrink, so expending it is reversing the process. I think it's worth a try if one knows how to write a code for it.
10 pixels over 720 is 0.014 of a pixel shift so it's still under the chroma resolution of 40 pixels a line, I think it will be the exact right solution.

[ringo1]

Some news on this one.

This should be the same frame, played with a Bauer VCC 816 AF, so it really doesn't seem to be on tape.

[Attachment 56812 - Click to enlarge]