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Pale color bt2020 > bt709 - Printable Version

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Pale color bt2020 > bt709 - gbedrune - 25.09.2021

Hi,

i use to re encode all my big size 4k video sometime 1080 sometime 4k ... since nvenc h265 is game changer ...

but i fail to proprely set the color sometime ...
[Image: 5yc4.png]

What is a equivalent of PQ in hybrid ?

1 = result

I try lot of setting ... style pale color ... had to use handbrake ... where the options are not even available so impossible to fail ... but for the rest he is too limited ...

Any idea thx?
 *
merciPlease, read the 'Infos needed to fix&reproduce bugs,..'-sticky before you post about a problem.

RE: Pale color bt2020 > bt709 - Selur - 25.09.2021

Hybrid doesn't support NVEncCs 'hdr2sdr' parameter.
--vpp-colorspace hdr2sdr=....
But you can add it through 'NVenc->Misc->Addition' for example:
--vpp-colorspace hdr2sdr=hable,source_peak=1000.0,ldr_nits=100.0,a=0.22,b=0.3,c=0.1,d=0.2,e=0.01,f=0.3
Make sure to adjust the options to your liking and source.
(You also might want to adjust the color matrix&co and set the "NVEnc->Misc->Video Usability Information" options accordingly.)

-> Read https://github.com/rigaya/NVEnc/blob/master/NVEncC_Options.en.md#--vpp-colorspace-param1value1param2value2 for details about hdr2sdr and other color space manipulation in NVEncC.

Cu Selur

RE: Pale color bt2020 > bt709 - shijan - 25.09.2021

PQ is same as smpte2084
It was always some randomness in naming between different tools used in Hybrid.

Here is full list if it helps (i prepared it as part of the unified naming structure for Hybrid, but it was never implemented by developers probably because each renaming like this require too many complex changes and adds new bugs):

--colorprim
Specify color primaries to use when converting to RGB. Default undefined (not signaled)
bt709 -> BT.709
unknown -> Unspecified
bt470m -> BT.470 System M
bt470bg -> BT.601 PAL
smpte170m -> BT.601 NTSC
smpte240m -> SMPTE 240M
film -> Film
bt2020 -> BT.2020
smpte428 ->XYZ
smpte431 -> DCI P3
smpte432 -> Display P3

--transfer
Specify transfer characteristics. Default undefined (not signaled)
bt709 -> BT.709
unknown -> Unspecified
bt470m -> BT.470 System M
bt470bg -> BT.470 System B/G
smpte170m -> BT.601
smpte240m -> SMPTE 240M
linear -> Linear
log100 -> Log (100:1)
log316 -> Log (316.22777:1)
iec61966-2-4 -> xvYCC
bt1361e -> BT.1361
iec61966-2-1 -> sRGB/sYCC
bt2020-10 -> BT.2020 (10-bit)
bt2020-12 -> BT.2020 (12-bit)
smpte2084 -> PQ
smpte428 -> SMPTE 428M
arib-std-b67 -> HLG

--colormatrix
Specify color matrix setting i.e set the matrix coefficients used in deriving the luma and chroma. Default undefined (not signaled)
GBR -> Identity
bt709 -> BT.709
undef -> Unspecified
fcc -> FCC 73.682
bt470bg -> BT.470 System B/G
smpte170m -> BT.601
smpte240m -> SMPTE 240M
YCgCo -> YCoCg
bt2020nc -> BT.2020 non-constant
bt2020c -> BT.2020 constant
smpte2085 -> Y'D'zD'x
chroma-derived-nc -> Chromaticity-derived non-constant
chroma-derived-c -> Chromaticity-derived constant
ictcp -> ICtCp

RE: Pale color bt2020 > bt709 - Selur - 25.09.2021

Quote:What is a equivalent of PQ in hybrid ?
PQ <> smpte2084, but just setting the 'Video Usability Information' will not change the colors, you need to do the mentioned hdr2sdr conversion.
(shijan was faster)

Quote:realized by developers probably
The is only one developer,... who unlike shijan seems to believe does not have unlimited time and motivation to jump around for him.

Cu Selur

RE: Pale color bt2020 > bt709 - shijan - 25.09.2021

Seems i missing the point. Did gbedrune attempt to convert bt2020 to bt709, or simply want to transcode HDR 4K to HDR 1080p?

RE: Pale color bt2020 > bt709 - gbedrune - 25.09.2021

woooww it was two jedi answer ... not even the time to brew the coffe :p thx gentlemen

RE: Pale color bt2020 > bt709 - Selur - 25.09.2021

Quote:Seems i missing the point. Did gbedrune attempt to convert bt2020 to bt709, or simply want to transcode HDR 4K to HDR 1080p?
From what I understood he wants to convert HDR (bt2020) to SDR (bt709) and thus hdr2sdr is needed.

Cu Selur