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  1. Member
    Join Date
    Dec 2002
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    United Kingdom
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    This is a screen grab from a DVD which I am trying to correct. In my humble opinion it has a GREEN cast/hue throughout the clip, What would be the best program/tool to use to, if possible correct it. From my limited photgraphy knowledge I recall having to "add" a different colour cast/hue to counteract the green one. Am I correct, Any advice is most welcome, Cheers

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  2. I'm a Super Moderator johns0's Avatar
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    Jun 2002
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    canada
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    Best thing to do is just adjust your TV hue so that it corrects the issue and save that as a user custom setting.
    I think,therefore i am a hamster.
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  3. Member
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    May 2014
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    Not bad, a little too red, has some blue in the blacks, gamma seems a bit low. ColorYUV can scale down red maybe 4 or 5 points in YUV. In RGB, bright red is slightly clipped . It's obvious in histograms. To correct red overbalance, either lower red offset or add cyan, or do a little of both. Country dust in the image should still look a little orange.

    VLC Player + Uncalibrated monitor = no way to judge color.

    Cyan added, dark blues lowered (VirtualDub gradation curve):
    Click image for larger version

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    Last edited by LMotlow; 11th Mar 2016 at 06:13.
    - My sister Ann's brother
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  4. The green hue thing seems to be common for PAL DVDs. I don't know why. Not all PAL DVDs have a green hue but I've seen quite a lot that do. Old and new.

    Not having found a better method I usually just dial back the green by a very small amount with Avisynth.

    ConvertToRGB().RGBAdjust(1, 0.97, 1).ConvertToYV12()

    For playing around in real time while previewing the source, ffdshow can be handy if you have it installed. The Picture Properties filter also has a "colorize" option which might be effective in small doses.

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    To use it while re-encoding you either need to be decoding the source via DirectShow, or if you've installed the Avisynth plugin with ffdshow you can use ffdshow's filters in Avisynth without decoding via DirectShow.

    Load_Stdcall_Plugin("C:\Program Files\AviSynth\plugins\ffavisynth.dll")
    ffdshow(preset="default")

    If the Picture Properties filter is enabled in ffdshow's decoder configuration, it'll be applied to the video. Don't use the "luminance level fix' option though. It auto-adjusts the luminance and like all auto-adjustments, it's not great.

    If you're not familiar with Avisynth, FFQueue has colour adjusting filters in it's configuration for creating encoding presets. I'm pretty sure Hybrid has colour adjusting options.
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