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  1. Hey - I have a source (retail DVD) I'm attempting to make a nice rip of, however there seems to be some sort of artifacting on line edges? Have no idea what the name for this is (although I have seen it before quite a few times), and it only appearing on the animated bits almost makes it seem as if it was introduced during production, not after. Although at the same time, it sorta looks analog related, like a result of a mediocre transfer. I don't know any of that for sure, just some silly guesses.
    Image
    [Attachment 48096 - Click to enlarge]

    It's particularly apparent here. Does anyone know exactly what this is, and if there's any way to remove or reduce it? Not expecting perfection, and if it's not something that can be reduced, it's not an end of the world thing. I've included a sample, as I know that goes quite a lot farther than a simple image. Major thanks for the help, and apologies for what is probably an incredibly noob-ish question, lol!
    Image Attached Files
    Last edited by MrColeslaw; 15th Feb 2019 at 16:34. Reason: added wrong image initially
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  2. Those are dot crawl artifacts.

    https://en.wikipedia.org/wiki/Dot_crawl

    AviSynth filters like CheckMate() can greatly reduce them. Another trick, at the cost of a little sharpness, is to scale the video to half width, then back to full width.
    Image Attached Files
    Last edited by jagabo; 15th Feb 2019 at 20:40.
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    Dot crawl is an artifact of composite video, which means that whoever mastered the DVD used substandard procedures.
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    I would use TComb(mode=0) right after your source filter. Also, after IVTC or deinterlacing use QTGMC progressive mode to finish wiping out the dotcrawl.

    QTGMC(preset="slow",inputtype=1,tr0=0,tr1=2,tr2=1, smode=0)

    Push the tr2 value to 2 or 3 if necessary.
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  5. This work fine generally with lots of dot crawl:
    avisource() # deinterlaced source
    main=last
    main
    bicubicresize(480,320)# for NTSC source
    spline64resize(720,480) # for NTSC source
    lsfmod
    filtered=last
    main
    mt_edge(mode="prewitt",chroma="copy").mt_expand # prewitt is more agressive/ use mode="min/max" otherwise
    mymask=last
    mt_merge(main, filtered, mymask)
    *** DIGITIZING VHS / ANALOG VIDEOS SINCE 2001**** GEAR: JVC HR-S7700MS, TOSHIBA V733EF AND MORE
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  6. If you want to learn more about how to remove dot crawl, search both this site and also doom9.org and search for:

    "dot crawl" AND "South Park"

    The early South Park DVDs were mastered in the same way and have the same artifact, and a lot of people provided advice on how to fix that problem.
    Last edited by johnmeyer; 17th Feb 2019 at 21:11.
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