Need help assessing an artifact

[Chainmax]

I am currently trying to backup some DVDs I bought a while ago and they cleaned up almost perfectly, except for this artifacting:


Source:
http://img407.imageshack.us/img407/2127/source.png

Filterchain:
http://img10.imageshack.us/img10/7941/filtered.png


It's not immediately seen, but in these sample pictures both the lower part of the vertical green pole and the cow's right suspender have some kind of ghosting. Now, the thing is it's not plain haloing as it's colored (besides, dropping the sharpening and adding EdgeCleaner did not solve the issue), and it doesn't seem to be chroma bleed as FixChromaBleeding did not make it budge.
What would you say this artifacting is and how would you deal with it (if possible or worthwhile, that is)?

You can find a vob sample here (http://www.mediafire.com/download.php?qzmfd5tywm2).

[thetoof]

A localized chromashift(C=x,L=y) would do the trick... but I see no way of targeting only the problematic areas.

I mean, if this is the only scene with the issue, you could always overlay a corrected portion of the frame, but unless you tweak the coordinates of the area manually, a blind application on the whole clip would be destructive.

As a side note, good job! Though your warp-sharpening seems a tad too strong to me ;)

[Chainmax]

Yeah, the whole episode suffers from this in varying degrees, so correcting each problematic frame and overlaying it would be a bit tiresome :). And thanks for the compliment, but why do you say the warpsharping feels too strong? Lines too thinned?

[thetoof]

So I can't be of any help on how to create a mask... I don't see anything that can be used to pinpoint the locations automatically.

Yeah, lines too thinned and minor haloing. Also, from my experience (no theoretical proof of any kind), blowing up in real time thin lines from a SD source to an HD screen, which is pretty much the norm now, makes aliasing more noticeable than thick and slightly blurred edges as your source has.

Unless you want to use nnedi2 upscaling to HD or if this is only intended for viewing on small screens, I'd be a little less aggressive.

[Didée]

For those chromatic edges, have you already tried aWarpSharp in its chroma-by-lumabumpmap mode (cm=1? 2? 3? can't remember offhand...), then use just chroma from that?

[Chainmax]

Nope, haven't tried yet.

/peeps at aWarpSharp2 documentation

aWS2's readme states that chrominance processing guided by luminance is done with the chroma=4 switch, so would this:

previous filtering
vid=last
MergeChroma(vid.aWarpSharp2(chroma=4))
final filtering

be what I need to try? Also, I assume it would be best put right before any resizing or (warp)sharping already present in the script, is that correct?


[edit]If so, doesn't seem to make much difference at all.

[Chainmax]

Hey, thetoof, since this is IIRC a U.S cartoon there's no chance this minor ghosting (or whatever it is) might be due to blending, is there?

[thetoof]

I don't think so... though I've seen some cases where chroma was swapped between 2 frames, but never only locally; it always affected the whole frame.
A few samples would be great.

[Chainmax]

Actually, the OP already had a 22s vob sample, I'll make it more visible.

[thetoof]

If it was due to blending, it wouldn't be present in all the frames. (i.e. you'd notice it when there's motion, not for the whole duration of a static sequence)

Having looked at the sample, I have no idea of the cause nor the solution for this, except maybe some mergechroma(awarsharp2(big ass value))... imo it's not worth the risk.

[Chainmax]

Hmm, gonna check slow motion parts and see what happens there. Pretty sure they still exhibit the problem.
It felt didn't like it was going to be worthwhile fixing. So, unless someone else toys with the sample and finds a solution, all I'll do is tweak the sharpening and warpsharping strengths. Then I'll try to capture the spanish audio from TV, as I think it's still being aired here occasionally. Thanks for the feedback, thetoof :).