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    This is an artifact appearing in a music video from a DVD.

    Any idea on what this is? And if so do you know of a way to reduce it within AviSynth?

    Just in case my script is causing it, here it is:

    Code:
    MPEG2Source("1.d2v")
    AssumeTFF() 
    QTGMC(Preset="Slow", FPSDivisor=2, Sourcematch=3, Edithreads=8) #deinterlace
    TDecimate() #retrores to 23.976
    Derainbow() #reduce rainbow
    Deblock_QED() #reduce blocking
    SmDegrain(tr=1) #remove grain
    ColorMatrix("Rec.601->Rec.709") #converts to rec. 709
    Spline64Resize(720,540) #conforms to 4:3 standard
    Sharpen(.1) #sharpens image
    And here is the video in which the artifacts appear: (uploading)

    Any help would be appreciated.
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  2. It's residual dot crawl from a composite capture. One of the easiest ways to remove it is to downscale the frame width by about half, then upscale again. It works pretty well with VHS caps because the low resolution of VHS isn't hurt by the downscale. A DVD source may show significant loss of sharpness though. There are lots of dot crawl removal filters for AviSynth. You can use masks to limit the fixes to edges with high color saturation.
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  3. Originally Posted by jagabo View Post
    It's residual dot crawl from a composite capture. One of the easiest ways to remove it is to downscale the frame width by about half, then upscale again. It works pretty well with VHS caps because the low resolution of VHS isn't hurt by the downscale. A DVD source may show significant loss of sharpness though. There are lots of dot crawl removal filters for AviSynth. You can use masks to limit the fixes to edges with high color saturation.
    Thanks. I was familiar with dot crawl but wasn't sure if this was it.
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  4. If this was generated during the capture, and if you are still doing the capture, you can often completely eliminate this artifact by using S-video connections from the VCR to the capture device. However, some sources have the artifact "baked in" from poor transfer by the DVD company from original sources. For instance, a lot of posts have been made both here and in the doom9.org forum about "South Park" dot crawl on DVDs.

    You can also do a pretty good job removing it with the proper blurring filter. I think I used a convolution plugin on one dot crawl source I had, although that one was B&W. I got some help with that in this thread:

    Remove cross hatch pattern from Kinescope
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