Quote:
Originally Posted by Bi11
I tried it but there are still some light-gray details in bright areas that aren't being seen.
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Somehow I have a suspicion. The suspicion that you are using a badly-calibrated (or badly-featured) LCD flatscreen, and that you're trying to work around bad brightlevel resolution.
Check e.g.
here - do you see "everything"?
Quote:
I don't know RPN very well, or how mt_lut should be used, but I tried:
[*wrong code*]
It shows light-gray details while still keeping white at 255.
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That code is not correct. Look at the histogram. There is a gap between 235-250, that range is not used at all, because of the wrong formula.
Quote:
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Since this clip is probably supposed to look like tv levels [16,235], I should ask how to properly convert TV->PC such that the video doesn't look like dynamic contrast is turned on.
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That's a misconception. A clip is not supposed to "look like" TV levels.
When a clip IS TV levels, then it looks correct on TV-levels display devices, and looks washed-out on fullscale display devices. And vice versa, a PC-scale clip will look correct on fullscale devices, and overcontrasted on TVscale devices.
Ah, I start getting lengthy .... anyway, what you are trying is solely a matter of personal preference. Not any kind of "correction" that would be "needed" to do.
FWIW ... generalized LUT function with "dark point" + "factor", and "bright point" + "factor".
Code:
point0 = 8
factor0 = 2.0
point1 = 247
factor1 = 2.0
P0=string(point0)
P1=string(point1)
F0=string(factor0)
F1=string(factor1)
mt_lut("x "+P0+" < x "+F0+" * x "+P1+" > 255 255 x - "+F1+" * - x "+P0+" - "+P1+" "+P0+" - 255 "+P1+" - "+F1+" * - "+P1+" "+P0+" - / * "+P0+" 2 * + ? ?")
There really should be a levels-filter that works with control points and splines, like those brightness/levels/whatever controls that we all know from most existing image graphic editors. More than a decade of Avisynth, and nobody did that yet ...