Filmation She-Ra Restoration - weird chroma issue (chromatic abberation?)

[oberonz]

I am trying to improve the HD version of She-Ra, Princess of Power which leaves a lot to be desired in terms of quality. One problem I can't seem to find a solution to is this weird chroma shift or bleeding that is noticeable in white or pale areas. A purple/reddish halo is clearly visible on the left of the area and a green halo is present on the right. In this sample image the problem can be seen on Beastman's face and Adora's left arm very noticeably but is also present in other areas of the image.

Here is a sample of the video. The problem is most prominent on Adora's white shirt:
https://files.videohelp.com/u/311562/00008.mkv

[lordsmurf]

Wasn't this another situation where the original masters were destroyed, and we've only been left with seconds, like the PAL version? It's a shame that He-Man.org is gone, as it documented things like this. (I was a member from 1998 to closure!) What we have is probably the best it'll ever get.

That said, I don't see anything green, and my monitors are calibrated.

[oberonz]

The original masters were never destroyed. That info came from a BCI rep. People kept pestering him on the org for a Blu Ray release. After saying no three or four times, he got fed up and said that Hallmark destroyed the masters after remastering them. This was not true. But no one is interested in making a new remaster of these cartoons. I've managed to drastically improve the He-Man ones but She-Ra has this weird color bleeding issue (that is not present in He-Man) and I don't know how to deal with it.

[october262]

The original masters were never destroyed. That info came from a BCI rep. People kept pestering him on the org for a Blu Ray release. After saying no three or four times, he got fed up and said that Hallmark destroyed the masters after remastering them. This was not true. But no one is interested in making a new remaster of these cartoons. I've managed to drastically improve the He-Man ones but She-Ra has this weird color bleeding issue (that is not present in He-Man) and I don't know how to deal with it.

see if this reddit thread will help -
https://www.reddit.com/r/davinciresolve/comments/xbqrom/anyone_know_how_to_fix_color_b...g_like_this_i/

[lordsmurf]

On my tablet, zoomed in, I see the chroma aberration.

[oberonz]

I know it doesn't seem a big deal but it makes darkening edges and any sort of color correction (with the source needs badly) impossible without exasperating the problem further. @October 262 thanks for the link but I don't think that has anything to do with this problem. That looks more like an encoding issue to me. This color problem is likely due to the way in which the source was captured back in the early 2000s and is hard coded there into any and all releases of the show including the Eternia Collection from which the screenshot is taken.

[buzz1891]

CA should be symmetric to lens axis , which seems to be not the case here. Must be something else. Consider color channels shift (left right) by subpixel accuracy

[lordsmurf]

I've not been paying close attention to MOTU releases, but I vaguely remember some sort of ultimate Blu-ray set in recent years. Is this part of that set? I was EU only, not in USA, apparently hard to get.

Anyway, I need a minute-long clip to play with. I have ideas.

[oberonz]

That's what I was thinking and shifting to the left by 0.7 pixels DOES help with the white/clear areas but then the red/dark areas get similar darker color bleeding. So my suspicion is that this shift occurred not in YUV space but in some other color space which I can't figure out or I am wrong and it's not channel shifting. I don't know.

@Lordsmurf, this is the Eternia Collection, the German set released two years ago that is the only HD version of He-Man and She-Ra available. The US Bluray version is just in SD. Note that the episodes are not remastered. They are the old Hallmark masters made in the 90s which were transferred from reels in 1440p but never released in any resolution higher than DVD until the EC. The idea they are newly remastered comes from a video on Youtube made by some... person... let's just say that (Sorry, I really don't like people putting misinformation on these shows that I love so much). Anyway the guy interviewed James Eatock about the EC. James said loud and clear these are not new remasters but the old Hallmark masters however the guy interviewing him kept interrupting him laying out some weird conspiracy theory that the EC is a new remaster and that James just isn't "allowed to say it". He even claimed to be a video expert and that he "knows" what he is saying in which case (if it were true) he would have noticed the weird chroma problem with She-Ra, the same identical and incorrect color correction on both releases and the weird temporal noise filters used on the early He-Man episodes again present in both DVD and Blurays which shows they are not NEW remasters. In fact James even noted that the temporal filter artifacts were present in both versions indicating they are the same master but the interviewer silenced him again even stating that James talked to him "privately" and that the EC is indeed a new remaster. So everyone on the org, reddit and elsewhere started to refer to these as a new HD remaster but in fact they are not. No doubt this is the best version we've ever seen but if they were truly remastered from reel with 2020's technology the results would have been a whole other thing.

Video specimen coming in a few minutes...

[Selur]

I would try BasicVSR++ on the chroma, usually it's good with such stuff.
If you can share a short sample, I can run it through BasicVSR++ for testing.

[oberonz]

I have updated the main post with a one minute specimen of the video. Thanks so much for the feedback, guys.

[Selur]

BasicVSR++ on its own doesn't help much, using BleedOut_Compact does a decent job.
Using mclean, BasicVSR++, BleedOut and some line darkening is slow, but does work fine (script), see: https://imgsli.com/Mjk2MzY4


Cu Selur

[lordsmurf]

Well, this is unexpected. I think the CA is also making the black toon lines thicker. You can use CCD in VirtualDub to remove the CA, but it affects certain tool lines. Looking before/after, it does appear the toon lines are "thicker" fuzzy from CA.

I don't have time at the moment, but I wonder how a WarpSharp would treat this.

There are others in my toolbox, I'd need to ponder for a bit, when I get some free time.

Yeah, I don't recall anything about a remaster, simply "the best" HD set to date. Yep, that's it, I remember, Eternia Collection.

[oberonz]

Thanks, Selur. That is a remarkable improvement although I would rather not use any AI models as I'd like to try and conserve as much of the original image as possible. I did line darken the He-Man episodes in DaVinci using a quite lengthy process namely extreme denoise a copy of the material, make it monochromatic, limiting the luma range of the histogram, then resizing to 4K(this is important to avoid ED causing artifacts) and then apply edge detect with low brightness and an edge thickness of exactly 0.11 (for He-Man - She-Ra is more blurry and will require a lower value). For some of the material I fed the result to Deflicker (with chroma turned off). For other parts that was not required. Then I turned the whole resized video to 1K into an alpha channel for a black background and superimposed it on the original. The result is quite radical while still being conservative at the same time. What I mean is that the video looks improved but all the shapes and details are left untouched. Here is a sample of the result I achieved with He-Man. Because of the chroma issue, doing the same for She-Ra seems very problematic.

He-Man source: https://files.videohelp.com/u/311562/source.mkv
He-Man result: https://files.videohelp.com/u/311562/result.mkv

This is just for reference. Neither the source nor the result (as far as I can tell) have any issues for He-Man, other than the fact that the colors in the source are all wrong for anyone who knows how the original show cels are supposed to look.

I think I will try the Bleedout_Compact that you suggested and blend with the original if I don't find a way to do it without AI. Also BasicVSR++ looks like an incredible tool. I am very impressed with it. I am not an anti-AI person. Actually I use it a lot but I like to leave it as a last resort to be as conservative as possible with the original material. Sometimes even if AI drastically improves a video it does so at the expense of losing some of the original features that may otherwise have been conserved with more traditional methods.

Thanks to you too Lord Smurf. Yes, the chroma issue causes the blurriness too. You nailed that. In fact the episodes with less chroma blur are sharper. Those with more are blurrier. The He-Man ones that have no chroma issues, also have no blur at all and playing with the YUV channels also makes the picture sharper for She-Ra but as I said at the expense of introducing artifacts in other parts of the image.

[Selur]

You need really high CCD values for CCD to help: https://imgsli.com/Mjk2Mzgw
aWarpSharp2 doesn't really seem to help: https://imgsli.com/Mjk2Mzg1

Cu Selur

[lordsmurf]

That CCD is too harsh. About 66% was a good happy compromise, to remove most CA, but not harm image.

I wonder if a mix of CCD, then re-run toon(), would have good results.

I also wonder how an anti-alias may affect it, aaa(), santiag(), etc
Also curious what deen() could do.
Several of these have adjustments to only attack chroma.
No time to try myself at the moment.

[lollo]

Using mclean, BasicVSR++, BleedOut and some line darkening is slow, but does work fine (script), see: https://imgsli.com/Mjk2MzY4

Excellent job, Selur!

[jagabo]

aWarpSharp2(depth=20, chroma=6) cleans up the chroma edges pretty well. Following with a small ChromaShiftSP(x=0.5) may help a little too.

[Selur]

Hmm,... one could do some masked deblur, thinning and antialiasing (script, where I used GLSL filers for this): https://imgsli.com/Mjk2NDU0
The problem is finding the right balance between these kinds of filters. (the masked debluring is probably the most critical part)
(personally I would denoise, the whole thing)

Cu Selur

[Selur]

aWarpSharp2(depth=20, chroma=6) cleans up the chroma edges pretty well. Following with a small ChromaShiftSP(x=0.5) may help a little too.

That kind of enhances the yellow colored chroma edges for me, but it does seem to help with the purple ones.
But yes, there are different approaches that might work and finding the right values might be the greates problem.

Cu Selur