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jpsdr · 1st August 2018, 08:34

Yes, there is "something wrong" : standard avisynth doesn't support RGB64 neither RGBPS, so, you need avs+.

8 bits creates too much precision loss on linear data on HDR video. You can easely see it just by doing, on 8 bit video (even if it's not an HDR video) the following (it will use for this test the PQ HDR path) :
ConvertYUVtoLinearRGB(Color=0)
ConvertLinearRGBtoYUV(Color=0)
Theoricaly, the ouput should be identical to the input, but you'll see effect of precision loss. So, doing HDRtoSDR functions on 8 bits data is a total nonsense (when your data are the linear sensor data).
This could be possible if you're doing a function which will do the 3 functions in one (YUV -> RGB -> HDRtoSDR -> RGB -> YUV) and working internaly with 16 bits data, but it's not the path i've choosen. I choose modular functions option.
So if you stay with standard avisynth, you'll not be able to use the specific HDR/SDR functions.

I've re-read again, and there is nothing wrong in the description of "ConvertXYZtoRGB" in the readme.

Yes, i'll integrate it later, after the 0.4.0, where i'll add Hable, Mobius and Reinhard (but again, they'll be usable only with avs+).
Expect 6 new functions like ConvertXYZ_Mobius_HDRtoSDR, ConvertRGB_Mobius_HDRtoSDR, etc...

1st August 2018, 08:34	#45 \| Link
jpsdr Registered User Join Date: Oct 2002 Location: France Posts: 2,316	Yes, there is "something wrong" : standard avisynth doesn't support RGB64 neither RGBPS, so, you need avs+. 8 bits creates too much precision loss on linear data on HDR video. You can easely see it just by doing, on 8 bit video (even if it's not an HDR video) the following (it will use for this test the PQ HDR path) : ConvertYUVtoLinearRGB(Color=0) ConvertLinearRGBtoYUV(Color=0) Theoricaly, the ouput should be identical to the input, but you'll see effect of precision loss. So, doing HDRtoSDR functions on 8 bits data is a total nonsense (when your data are the linear sensor data). This could be possible if you're doing a function which will do the 3 functions in one (YUV -> RGB -> HDRtoSDR -> RGB -> YUV) and working internaly with 16 bits data, but it's not the path i've choosen. I choose modular functions option. So if you stay with standard avisynth, you'll not be able to use the specific HDR/SDR functions. I've re-read again, and there is nothing wrong in the description of "ConvertXYZtoRGB" in the readme. Yes, i'll integrate it later, after the 0.4.0, where i'll add Hable, Mobius and Reinhard (but again, they'll be usable only with avs+). Expect 6 new functions like ConvertXYZ_Mobius_HDRtoSDR, ConvertRGB_Mobius_HDRtoSDR, etc... __________________ My github. Last edited by jpsdr; 1st August 2018 at 08:59.