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  1. Member hydra3333's Avatar
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    Hello.

    Attached is a 17Mb example source (from VHS recorded in 1984, no other capture available).

    It has what looks like may be

    (a) a small colour shift right (VHS tape copy?) eg on the white shirts at the 1 second mark, although that looks "wrong" on the flagpoles at the 17 second mark
    (b) and something which may be a heavy "Ghost" but could be something else I don't know the name of, given what appears to be an associated heavy colour shift to the right

    Attached is 13Mb beginning of to address it, deblock/cropbottom/cnr2/mdegrain3/chromashiftSP(x=2)/qtgmc.

    Your expert advice would be greatly appreciated about what the large ghosting-type artifact is, and perhaps suggestions on how to address it.

    Thank you.
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  2. Better in some areas, worse in others.
    Code:
    src = last
    Overlay(last, last.Invert(), x=11,  y=0, Opacity=0.20).ColorYUV(cont_y=165, cont_u=165, cont_v=165)
    Overlay(last, src, mask=ColorYUV(cont_y=150).Invert(), opacity=0.7)
    Chroma may need slightly different treatment.
    Last edited by jagabo; 25th May 2021 at 04:56.
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  3. Originally Posted by hydra3333 View Post
    .... what the large ghosting-type artifact is ....
    Could be signal reflections due to long cables with wrong impedance termination between the VCR and the capture device.

    Edit: Unlikely. A second thought indicates that for practical cable lengths the echo ghost is less than 1...2 pixel delayed.
    Last edited by Sharc; 25th May 2021 at 07:00.
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  4. OTA multipath reception.
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  5. Member hydra3333's Avatar
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    Thank you. It is ghosting, then. Wasn't sure what "Halo" meant (if it was different) and if it was that or something.

    Originally Posted by jagabo View Post
    Better in some areas, worse in others.
    Code:
    src = last
    Overlay(last, last.Invert(), x=11,  y=0, Opacity=0.20).ColorYUV(cont_y=165, cont_u=165, cont_v=165)
    Overlay(last, src, mask=ColorYUV(cont_y=150).Invert(), opacity=0.7)
    Chroma may need slightly different treatment.
    Good oh, I'll look these up in the Wiki and try them as a starting point.
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