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  1. Member
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    This was captured as I always do.. dscaler with "simple weave" using lagarith (720x480i) from my VCR.. no processing at all..

    When I use bob deinterlacer in virtualdub I get a field which seems to be also interlaced.. when zooming it shows horizontal black lines which rolls from bottom to top..

    What the heck is going on??!! How can I repair this? QTGMC would help? This is the tape from a friend's 15yo birthday.. there is another tape with this same content and same problem.. (they both must be a copy)

    Please download this sample.. it's lossless (lagarith).. http://www.megaupload.com/?d=JL1V8W0H

    The attached pic is a FIELD.. which obviously shouldn't be interlaced(!).. grabbed from virtualdub output after bob deinterlacing
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    Last edited by Heiler; 19th Oct 2011 at 23:41.
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  2. I have said it before but never use dscaler to capture videos or expect funky effects such as this.Do it with virtualdub or ChrisTV or virtualvcr (free)
    *** DIGITIZING VHS / ANALOG VIDEOS SINCE 2001**** GEAR: JVC HR-S7700MS, TOSHIBA V733EF AND MORE
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    As well as the tools mentioned above, I've had good luck with a program called Stoic, it's in the tools section here.
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    This has nothing to do with dscaler, guys.. I have done lots of flawless captures using it.. it accesses my cx2388 directly and has a lot more options than using a vanilla directshow capture (which gives me some blue-screens (not of death) when the signal is weak)..
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    It's got nothing to do with interlacing - it's noise/interference, either when the video was shot, copied, or captured. I bet it's been there all along - it's not so noticeable when watching the video at normal speed.

    There might be an fft3d filter setting for just this kind of thing, but I don't have a clue. You could ask at doom9.

    FWIW I think your capture would look better with a line TBC - there's wobbling and distortion. But that's a separate problem.

    Cheers,
    David.
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  6. If you're forced to work with the video as-is you can "fix" it with this:

    AviSource("ampex-cut.avi")
    SeparateFields()
    Blur(0, 1.0)
    Sharpen(0, 0.7)
    Weave()
    Or:

    AviSource("ampex-cut.avi")
    SeparateFields()
    VInverse()
    Weave()
    At the cost of a little blurring.

    Note that VirtualDub has problems with interlaced YV12 video. I would convert to YUY2 before giving it to VirtualDub.
    Last edited by jagabo; 20th Oct 2011 at 08:11.
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  7. I just had a batch of clips with the exact same problem. I used Defogger From Noise or the DFN filter in VDUB. It was very effective. The filter almost seemed designed to notice those black lines and rub them out. I also am a big fan of camcorder color denoise in VDUB, it will help your footage.

    DFN softened the image a bit but I was able to get the edges back using the Vegas sharpen.

    It's a weird problem. I had it on some VHSC tapes. The odd thing is that out of all the VHSC tapes recorded by the same camera, same tape brand, captured the same way, and some in the same location, only a few of them had this horizontal stripe issue.

    At first it looked like there was electrical noise, like 60hz hum. Maybe I used the battery on some and AC/DC adaptor on others, no way to tell.

    Also wanted to add:
    Try Removedirt to get rid of those purple and yellow chroma splotches.
    Use QTGMC (slow) and keep both fields for a 59.94fps output. Keeping and bobbing both fields may help "fill" in the gaps on those stripes.
    Last edited by magillagorilla; 20th Oct 2011 at 11:43.
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    Originally Posted by jagabo View Post
    If you're forced to work with the video as-is you can "fix" it with this:

    AviSource("ampex-cut.avi")
    SeparateFields()
    VInverse()
    Weave()
    At the cost of a little blurring.

    Note that VirtualDub has problems with interlaced YV12 video. I would convert to YUY2 before giving it to VirtualDub.
    wow, thanks, this vinverse() was fantastic.. no horizontal stripes anymore
    I don't know if anything can be better than that.. I'm trying qtgmc also..
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    magillagorilla, DFN didn't help much with the black stripes.. it seems good to remove some "normal" noise though..

    I couldn't get qtgmc to help me yet.. it has some repair options for progressive material with bad deinterlacing, not for a interlaced material with black stripes in its fields.. any ideias how to use it for that?!
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  10. QTGMC isn't going to help with that at all.
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    Originally Posted by jagabo View Post
    QTGMC isn't going to help with that at all.
    I thought that could be a way for it to reconstruct the missing lines or something..
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  12. There's a pattern of two light lines, two dark lines, two light lines two dark lines... all the way down the video. They swap with every frame. There's also a discontinuity in the middle of the video.

    The above filter chains work by separating the fields, leaving each field with alternating light and dark lines. Then the lines are averaged together so that they have equal intensity. Finally the fields are woven back into interlaced frames.
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  13. vinverse seems ideal

    for frames 363-364 in your sample:
    morph(362,365) # DvDropout Script (see doom9 forum)

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  14. Originally Posted by themaster1 View Post
    morph(362,365) # DvDropout Script (see doom9 forum)
    In case the OP finds that a bit cryptic: morph replaces frames 363 and 364 by interpolating motion between frames 362 to 365. It eliminates the little horizontal lines that appear above the letter K by completely replacing the frames. It works well for linear motions like that.
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  15. Originally Posted by jagabo View Post
    QTGMC isn't going to help with that at all.
    I'm not suggesting to use QTGMC to repair the problem. I'm suggesting it as the deinterlacer since the OP is deinterlaceing. It's a really good one. Also, that disgarding one of the fields may increase the problem.

    The horizontal lines in my footage were not as stark. This may be why DFN was able to smooth them them out on mine.
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  16. Originally Posted by magillagorilla View Post
    Originally Posted by jagabo View Post
    QTGMC isn't going to help with that at all.
    I'm not suggesting to use QTGMC to repair the problem. I'm suggesting it as the deinterlacer since the OP is deinterlaceing.
    Sorry, I misunderstood.
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    The output will be a dvd (interlaced).. I deinterlaced just to check what was going on in its fields..
    I thought of using qtgmc to fill the gaps or give more stability then reinterlace again but I think it won't help much, right? I don't care about speed.. :P
    I'm thinking of using MCTemporalDenoise also.. :P

    Anyway couldn't find the "DvDropout" script.. google didn't help.. just found "depulse"..
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    Originally Posted by Heiler View Post
    Anyway couldn't find the "DvDropout" script
    The original DV dropout thread (with the morph() function) is here:
    http://forum.doom9.org/showthread.php?t=128649

    Mug Funky posted a later version updated for mvtools2 (and I then suggested some improvements) here:
    http://forum.doom9.org/showthread.php?t=161154
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    hum.. right.. got it.. but for those horizontal lines, which are on the whooooole 2h clip, I would have to call morph for every 3-4 frames? and I'd end up with a total motion blur, right? then I should only use it for random dropouts, right?
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    Yes, morph is really designed for the odd random dropout here and there, not for a systematic problem throughout the video.
    It doesn't produce motion blur, though - it synthesises new frames by motion-compensated interpolation. Obviously, the larger the gaps you have between 'good' frames and the more motion between frames, the less accurate it becomes and the more artefacts it introduces.
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  21. @Gavino
    Isn't it because of the mvtools v1? I suspect that if this script is updated a bit it would be even greater.The other day i noticed this flaw for example on a 3-4 frames gap with a moving hand, on the third frame the hand almost disapeared (poof like Houdini) :/
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    The second link I quoted above is a version for mvtools v2, but I don't think it materially changes the results, just a different syntax.

    With a 3-4 frame gap (instead of 1 or 2), there is certainly more risk of the interpolation 'going wrong', especially if there is a lot of motion beween the two end-points, objects moving into or out of the picture or behind others, etc.
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  23. Motion interpolation only works well with very simple motions. It's great for panning shots, an object moving smoothly over a flat background, etc. But complex motions like body parts moving and rotating or turning can get very screwed up.
    Last edited by jagabo; 22nd Oct 2011 at 18:16.
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