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  1. What are these horizontal flickering rainbow like bar/streaks?
    Is there anyway to remove them?

    Image
    [Attachment 59205 - Click to enlarge]
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  2. I'm sure there is a terminology used to describe it, I just do not know what it is, so cannot even search for a possible answer.

    That's not me driving btw
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  3. Video Restorer lordsmurf's Avatar
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    Chroma noise

    best = recapture with S-VHS VCR with line TBC + DNR
    decent (usually) = CCD filter in VirtualDub
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  4. Originally Posted by lordsmurf View Post
    Chroma noise

    best = recapture with S-VHS VCR with line TBC + DNR
    decent (usually) = CCD filter in VirtualDub
    Already captured with S-VHS TBC + DNR.

    I am unable to use VirtualDub for capturing as it does not support the Avermedia CE310B capture card, and Avermedia's own capture software has no options.

    What I am asking for is which Avisynth filter is used to deal with this? Maybe nothing can, but I am just asking.
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  5. Originally Posted by agisthos View Post
    What I am asking for is which Avisynth filter is used to deal with this? Maybe nothing can, but I am just asking.
    You could try CnR(), DeRainbow() for example. See "Rainbow & Dot Crawl removing" section in the avisynth wiki.
    http://avisynth.nl/index.php/External_filters#Rainbow_.26_Dot_Crawl_Removal
    When you upload a short video sample you may get better advice.
    Last edited by Sharc; 1st Jun 2021 at 02:16.
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  6. https://mega.nz/file/qN1iyL5J#qxiINlspv9cn4ahWOIE5C5E3EmIcsihbNj7DDp6yx6o

    This is the worst clip I have come across so far in my tapes. CnR2 did not seem to do anything.
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    Chopperdore!
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  8. How about this?
    Image Attached Files
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  9. Originally Posted by Sharc View Post
    How about this?
    That very good, over 90% removal. How did you do it?
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  10. Originally Posted by agisthos View Post
    That very good, over 90% removal. How did you do it?
    A bit of butchering. There were not too many details in the source though.
    Code:
    AVISource("burnout.avi")
    converttoYV12(interlaced=true)
    assumeTFF()
    separatefields()
    AddGrainC(3)
    e=selecteven().Derainbow(1).Derainbow(1).MCDegrainSharp()
    o=selectodd().Derainbow(1).Derainbow(1).MCDegrainSharp()
    interleave(e,o).assumefieldbased().weave()
    QTGMC()
    Image Attached Files
    Last edited by Sharc; 1st Jun 2021 at 14:30. Reason: AddGrainC(3) added
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  11. Thanks Sharc that is a great help.

    Ok noob question here, I notice with a lot of Avisynth scripts you guys separate the fields to apply filtering to odd and even, then weave back together afterwards.
    Obviously it was required in this case.

    Generally, what filters/problems also need fields separated?

    Is it anything applied pre-deinterlacing ? Or only in cases of chrome noise like this?
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  12. Many (most) of the filters are are not interlace-aware and apply for progressive footage only. Without field separation or bobbing the 2 field would get mingled (->artifacts).
    For the grouping of the fields as top and bottom fileds, the general recommendation is, AFAIK:
    - for spatial filters only: SeparateFields -> filter -> weave
    - for temporal filters only: just filter
    - spatial-temporal filters: Separatefields -> SelectEven.filter -> SelectOdd.filter -> interleave -> weave

    Sometimes one has to try what looks best.

    Perhaps more knowledgeable members might chime in.
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    I am not more knowledgeable, but I use a slightly different approach:

    The options for filtering interlaced material are the following (the mode X naming is my coding):

    Spatial filter (I use modeD as you):

    mode D
    SeparateFields()
    <filtering>
    Weave()

    Temporal filter (I use modeA as you):

    mode A
    <filtering>

    mode C
    <Bobbing deinterlacer>
    <filtering>
    SeparateFields()
    SelectEvery(4,0,3)
    Weave()

    Spatial-Temporal filter (I use modeC instead of modeB):

    mode B
    SeparateFields()
    SelectEven().<filtering>
    SelectOdd().<filtering>
    Interleave()
    Weave()

    mode E
    JDL_UnfoldFieldsVertical
    <filtering>
    JDL_FoldFieldsVertical

    mode C
    <Bobbing deinterlacer>
    <filtering>
    SeparateFields()
    SelectEvery(4,0,3)
    Weave()

    Some reference:
    https://forum.doom9.org/showthread.php?t=86394
    https://forum.doom9.org/showthread.php?t=167315
    https://forum.doom9.org/showthread.php?p=1618309
    https://forum.doom9.org/showthread.php?t=59029

    I normally reinterlace back after filtering, so I use a lossless deinterlacer, nnedi3(field=-2). I do not use QTGMC lossless because it performs denoising, that I prefer to run separately. This will probably change when TemporalDegrain2 will be integrated in QTGMC in a stable release (an attempt here https://forum.doom9.org/showthread.php?p=1935157#post1935157)

    Some images for comparison (from an old experiment) here: http://www.digitalfaq.com/forum/video-restore/11586-reinterlace-best-practices.html#post75768
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  14. Very handy guide lollo.
    For denoising so far I have found TemporalDegrain2 to work better than QTGMC inbuilt EZdenoise and better than DFTTest.

    So to get this right, 'Temporal' denoisers must go after deinterlacing- but some denoisers are 'spatial' and should be used on separated fields before deinterlacing.
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    Very handy guide lollo.
    It's not mine, but the summary of the doom9 guru's recommendations. I just did some experiment, and found it appropriate.

    For denoising so far I have found TemporalDegrain2 to work better than QTGMC inbuilt EZdenoise and better than DFTTest.
    TemporalDegrain2 is my favourite denoiser too . Soon it will be implemented in QTGMC in a definitive manner, I hope!

    So to get this right, 'Temporal' denoisers must go after deinterlacing
    In principle, there is no need to deinterlace if you apply a pure Temporal filter. However, many do it anyhow because the temporal radius can be divided by two and the denoiser can smooth the motion on 2x frames.

    but some denoisers are 'spatial' and should be used on separated fields before deinterlacing.
    For a pure Spatial filter modeD is correct, and there is no reason to deinterlace to improve denoising effectiveness.

    Sometime I used a spatial filter like NLmeans family to create a denoised clip for better motion compensation inside old TemporalDegrain. With TD2 is not possible, it uses QTGMC tecnique for the motion estimation, and no external clips can be provided.
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  16. Video Restorer lordsmurf's Avatar
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    Originally Posted by agisthos View Post
    I am unable to use VirtualDub for capturing
    CCD is not run during capture.

    For really nasty chroma errors, there are some scripts that mostly use KNLmeansCL.
    I thought I had a thread here at VH, but can't find it.
    Last edited by lordsmurf; 2nd Jun 2021 at 22:36.
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