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View Full Version : Translating HDR metadata to something usable in x265


TEB
19th December 2017, 10:28
hi. Im quite the newb in the HDR world and i recently got some testfiles from one of our content vendors presenting this:

SMPTE ST.2086 METADATA:
- PRIMARIES STANDARD: P3
- WHITE POINT: D65
- LUMNINANCE MIN: 0,005
- LUMINANCE MAX 1000

MaxFALL/MaxCLL METADATA:
- MaxCLL: 999
- MaxFALL: 451

So im trying to build a x265 syntax that can cater for this input and based on some googeling im down to:

--colorprim bt2020 \
--transfer smpte-st-2084 \
--colormatrix bt2020nc \
--master-display "G(13250,34500)B(7500,3000)R(34000,16000)WP(15635,16450)L(10000000,50)" \
--max-cll "999,451"

Some questions:
1. What is whitepoint D65, and where does it fit in here?
2. I seem to be missing the X,Y primaries for RGB here. Can i use these presented values as "default" ??
3. Is my rationale behind the Luminaries right ?

br TEB

From the manual:

--master-display <string>
SMPTE ST 2086 mastering display color volume SEI info, specified as a string which is parsed when the stream header SEI are emitted. The string format is “G(%hu,%hu)B(%hu,%hu)R(%hu,%hu)WP(%hu,%hu)L(%u,%u)” where %hu are unsigned 16bit integers and %u are unsigned 32bit integers. The SEI includes X,Y display primaries for RGB channels and white point (WP) in units of 0.00002 and max,min luminance (L) values in units of 0.0001 candela per meter square. Applicable for HDR content.

Example for a P3D65 1000-nits monitor, where G(x=0.265, y=0.690), B(x=0.150, y=0.060), R(x=0.680, y=0.320), WP(x=0.3127, y=0.3290), L(max=1000, min=0.0001):

G(13250,34500)B(7500,3000)R(34000,16000)WP(15635,16450)L(10000000,1)

sneaker_ger
19th December 2017, 12:28
1., 2.:
x265 doc has example for P3D65, WP and everything else is already correct.
https://en.wikipedia.org/wiki/DCI-P3#System_colorimetry
3. Yes