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Old 22nd June 2018, 09:03   #27  |  Link
jpsdr
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Join Date: Oct 2002
Location: France
Posts: 2,309
I have no needs for PQ to HLG for now. But technicaly, once i'll implement the HLG in the plugins (because for now there is only PQ, my plugins have a HLGMode parameter, not implemented yet), doing something like :
Code:
ConvertYUVtoLinearRGB(Color=0,HLGMode=true)
ConvertLinearRGBtoYUV(Color=0)
will do the convertion.
I didn't implement HLG yet, because i've trouble to understand properly how it works. There is several range mode (so i'm a little loss).
But...! Maybe the doc you provided will help me to understand things. But, HLG is not my prority for now.
Ah... Just take a look. The french version and english version of the same release version document don't say the same thing.
French version (R-REC-BT.2100-1-201706-I!!PDF-F) talk of [0:12] range and possibility of [0:1], when english (R-REC-BT.2100-1-201706-I!!PDF-E) talk only of [0:1]...
Nice !

Edit :
Quick look, it seems that PQ has fixed parameters functions, for luminance range up to 10000 cd/mē. It seems that for HLG, the parameters changes according (Lw/Lb) values, when they are fixed for PQ. Meaning i'll have to add these parameters on my plugins, for when i'll implement HLG. I'll also have to add some "WhitePeak" value (at least on plugins using linear data on input), if i want to properly handle both HLG and PQ, because it seems that i can't assume (like i thought), that in linear value, 1.0 = 10000 cd/mē.
Well... I'll see this for later... when i'll do the 0.3 release
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Last edited by jpsdr; 22nd June 2018 at 09:34.
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