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  1. I need help trying to clean up this film, I attached a sample below. Throughout out the film I noticed alot of noise I think around certain objects. Any avisynth filter can clean this up abit. The file says its progressive but I think its interlaced. Thanks alot for your help.

    The source is from a dvd.

    Examples:


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  2. I'm a Super Moderator johns0's Avatar
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    That problems is caused by using too low of a bitrate,not much you can other than re-encode with a softening filter for mosquito noise.
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  3. Originally Posted by johns0 View Post
    That problems is caused by using too low of a bitrate,not much you can other than re-encode with a softening filter for mosquito noise.
    Ok thanks for your help ill google around
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  4. It's a mix of hard and soft telecine, with some true video and some weird crap maybe caused by it being edited on video. I don't guess the body of the movie is like this so you probably want to make it 23.976fps. A standard IVTC (with strong post-processing) will leave a few parts playing jerky.
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    A lot of the "noise around objects" is known as "dot crawl" . Read up on some dot crawl filters and approaches to deal with it .
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  6. I'm a Super Moderator johns0's Avatar
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    That's not dot crawl,it's mosquito noise as i stated.
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    Originally Posted by johns0 View Post
    That's not dot crawl,it's mosquito noise as i stated.

    Did you examine the video ? Or just the lossy jpeg image which distorts the dot crawl artifacts?

    The "artifacts around certain objects" that he's probably referring to are mostly dot crawl. Yes, there is also some mosquito noise , macroblocking and DCT ringing, but he's probably not referring to that

    Name:  dotcrawl.gif
Views: 219
Size:  110.4 KB
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  8. I'm a Super Moderator johns0's Avatar
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    I was referring to the image he posted as a closeup,Its the same as in the video.That's mosquito noise,the dot crawling is bad enough but its the closeup pic that the op was referring for the artifacting,not any dot crawling.
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    Originally Posted by johns0 View Post
    I was referring to the image he posted as a closeup,Its the same as in the video.That's mosquito noise,the dot crawling is bad enough but its the closeup pic that the op was referring for the artifacting,not any dot crawling.
    Yes, there is some mosquito noise and you're looking partly at jpeg compression artifacts (it looks like he took some jpegs then zoomed in and took a png screenshot, but the degradation is in the original jpeg), and there are other types of noise - but it's mostly from dot crawl .

    It's not from using too low of a bitrate. Using a lossless encode from the source before the DVD would just preserve the dot crawl artifacts more

    Here is a PNG of roughly those frames on that cropped area

    Name:  dotcrawl2.png
Views: 195
Size:  205.9 KB
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  10. okay thanks alot for your help whats a good dot crawl filter?
    Right now im playing around with Checkmate and Tcomb
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    Last edited by sanlyn; 19th Mar 2014 at 07:05.
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  12. Try something like:

    Code:
    Mpeg2Source("Intro.d2v", CPU=6, Info=3) 
    CheckMate(thr=10, max=20, tthr2=0)
    BicubicResize(480, 480)
    QTGMC(preset="fast")
    MergeChroma(aWarpSharp2(depth=5), aWarpSharp2(depth=20))
    FFT3DFilter(sigma=1.0, bt=3, plane=0)
    Sharpen(0.5,0.3)
    nnedi3_rpow2(2, cshift="Spline64Resize", fwidth=720, fheight=480)
    The result is slightly blurred and there's a slight loss of detail.
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