10bpc/30bpp color on win10 + radeon

[cirthix]

Hi,
I've been doing some testing with 10bpc color. Using an rx580 with latest drivers under win10, the monitor is operating in 10bpc mode, but the system is not.


I can view a 10bit gradient (it bands the same as 8bpc) and look at the raw pixel values in the output device. 1023, 1019, 1015 exist, but 1022, 1021, 1020,1018,1017,1016 and so on do not occur. Essentially, the graphics driver is receiving an 8bpc image and outputting a 10bit image by mapping it to the 10bit space, not allowing native 10bit operation.

I'd like to ask any users which have 10bpc capable displays running win10 to run this test app from NEC to see what it says.
http://www.necdisplay.com/documents/Software/NEC_10_bit_video_Windows_demo.zip

See the screenshot for additional information. (same thing happens in single-connection 4 k60 mode)

 

[zone74]

You need a professional GPU for >8-bit color in OpenGL, only Direct3D is supported on consumer GPUs.
As far as I can tell, this is an artificial restriction purely to lock people out of >8-bit color in professional applications like Photoshop.
I think this software is only supported on Windows 7 too, since it has to disable the DWM, and you can't do that on Windows 8/10 in a windowed application.
That may have changed now, but most documentation still lists support for only Windows 7.

GPU LUT adjustments (monitor profiles), the madVR video renderer, and the game Alien: Isolation is the only software I'm aware of which outputs >8-bit color on consumer GPUs. On NVIDIA hardware anyway.