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  1. Banned
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    Oct 2004
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    The attached clip comes from the old Wonderful World of Disney film, "The Hunter And The Rockstar". It was transferred from VHS. I rarely do VHS captures and most of what I do has been black and white captures, which I can manipulate OK n AviSynth. This clip really challenges me as the whites are insanely bright starting around the 6 second mark and while I've been able to use Tweak with the contrast and brightness settings to get this down a bit, the colors look very bad. I just found out today that this film is on DVD, so I'm not asking anybody to devote significant amounts of time to this, but I wanted to see if anyone had any suggestions on settings that might get this looking better. Messing with any Tweak settings beyond contrast and brightness is just making my output look worse, so I'm posting this as a learning exercise for me so I can look at what the gurus would do and try to learn from it should I encounter something similar in the future.
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  2. Member
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    Is this the original capture? It looks as if the white details have been crushed. Does the tape look this washed
    out when you watch it on the TV?
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  3. The brights have been crushed even though they are not particularly bright. You won't get much more detail out of them but you could try something like


    Code:
    ffVideoSource("Hunter-test.mkv") 
    src=last # remember original
    
    mask=greyscale().ColorYUV(cont_y=100) # build an alpha mask from the luma
    ColorYUV(gain_y=-133, gamma_y=-200, off_y=140) # stretch brights
    Overlay(src,last,mask=mask) # overlay new brights over original, retain original darks
    
    StackHorizontal(src,last) # see original and processed side by side
    TurnRight().Histogram().TurnLeft()
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  4. Banned
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    davexnet - Yes that is the original capture. Yeah, it looks like that on TV.

    jagabo - Thanks. I'll give your suggestions a test. That's way beyond what I know how to do. Very interesting.
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  5. Member
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    I've never seen that script technique before either, seems to tame the brights slightly and bring out a little shadow detail.
    Quite subtle, but strangely effective.
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  6. It's just a gamma adjustment, limited mostly to the brighter areas:

    Click image for larger version

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    On the left is a (mostly) straight greyscale ramp. In the middle the result of ColorYUV(gain_y=-133, gamma_y=-200, off_y=140), on the right the result of mixing the source and the adjusted image via the alpha mask.
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  7. Banned
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    jagabo - I used your script (minus the split screen after seeing that the first time) and the output was a lot better than what I was getting on my own. Thank you very much for that. I have some new information to dig into now.
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