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  1. I need to get the max Y-value per frame and just got stuck with all that runtime stuff.

    So, how do I get a variable for the maximim Y value and (depending on that variable) do something to the clip:

    if Y > 16 --> autolevel

    else

    --> do nothing
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  2. Runtime filters (eg AverageLuma, YPlaneMax) can only be used with runtime functions (eg conditional filter, scriptclip)

    Code:
    src=last
    
    src
    #your filter here
    filtered=last
    
    ConditionalFilter(src, filtered, src, "YPlaneMax", ">", "16", show=true)
    Just replace #your filter here, with whatever filter e.g. autolevels() . To debug it , use show=true to show the value of the conditional. You might have to adjust the 16 value slightly. Change it to show=false for the real thing
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  3. Thanks poisondeathray!

    It works. Not perfect but result is much better than before. The problem I'm having with all "autolevels" scripts/plugins is that they also
    "crank-up" black fades and crossfades, which looks really bad.
    After setting the Y-level to 40 almost every frame in the fade/crossfade remains dark except a few at the start and end.
    I can live with that though.

    Thanks again for your help!
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  4. Have you tried the other "autolevels" plugins ? (there are a few variations of "autolevels", and a different one called "autogain" by lato) . Lato's works the best overall IMO, but "auto" anything is prone to problems in general . It has a dark_exclude parameter which allows you to exclude a percentage of the darkest pixels in the minima calulation
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  5. I tried all of them. From ColorTuv(autogain=true) to several VD-filters. Also Lato's.
    They all fail when handling fades-in or crossfades thru black.

    But when using your script and setting the minY level to 75, the results are quite acceptable.

    Thanks again PDR!
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  6. Banned
    Join Date
    Oct 2014
    Location
    Northern California
    Search PM
    PeterNL, out of curiosity why do you need this?
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  7. I got some old super8 homevideos laserscanned to lossless AVI.
    The luma-levels are not constant and vary a lot because of the lousy camera i had at that time
    Beside that, I will put them only on my Dune mediaplayer so there is no need for studio-levels either and I prefer 0-255 levels.
    Doing this manually is a nogo so autolevels is my way to go.
    I edit them, render the complete project to some lossless codec and push them thru avisynth/virtualdub to get the right levels which worked well, except for the fades/crossfades. Finally I render to X264.
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