[Interest] HDR 10/ HDR Dolby support?

[Allan Sandfeld Jensen]

On Dienstag, 15. Mai 2018 19:48:03 CEST Boudewijn Rempt wrote:
> On dinsdag 15 mei 2018 19:00:53 CEST Allan Sandfeld Jensen wrote:
> > They only way I know of doing that at all at the moment is on Windows and
> > only using fullscreen mode, and the monitor probably only supports it
> > though HDMI. We are missing the proper standards for mixing HDR and SDR
> > content, and for Linux, we lack the GLX, X11, Wayland and OpenGL
> > standards,
> > though in theory you can do it through EGL, but I haven't found support
> > for
> > it, so I haven't been able to tell how it would work and how we should use
> > it.
> 
> Yes... That's one thing I was wondering about. I am getting a lot of push
> towards creating an HDR image authoring application (like Krita), but not a
> lot of details on how this would work and with which technologies.
> 
> > Btw, if you have HDR support in Krita, how do you handle the difference
> > between relative SDR colors (0-1.0) and absolute HDR colors (0-12.0)? Do
> > you have a color wheel that allows for the imaginary colors HDR uses
> > (whiter than white, bluer than blue).
> 
> Well... Those float numbers don't really mean much. It's a matter of
> scaling, and people in the VFX world I've been talking to author HDR images
> in Nuke or Natron with any scale, and then tone-map to 0..1.0, which is
> still HDR, because it represents a scale wider than SDR images.
> 
Yes, but that is old style HDR with just higher color-space resolutoin. The 
weird thing about the new HDR that we have in new HDR screens is this concept 
of colors beyond the otherwise brightest white. Imagine you set the brightest 
white you can have on the screen while still being comfortable to look, at 
(1.0,1.0,1.0) and then you can have white whiter than that for special 
effects. That is the new HDR. So a combination of higher color resolution a 
new color-space and "imaginary" colors above the otherwise maximum brightness, 
this makes perfect sense for 3D light effects but not much else, which is 
while I find it cool am not entirely sure what it would be good for in our 
case.

In theory you could just turn up the maximum brightness and use the extra 
resolution to reserve part of the scale, but that is not how the new HDR 
standards are operating. As far as I know photo and image HDR works more 
classically and doesn't require as much special support. You could just use 
OpenGL with FP16, many drivers support that, and more are adding it recently, 
though we don't have good interaction with it in Qt. If you need better 
support of that classic HDR, it should be easy to add, just say what you are 
using. At least we should be able to output it as RGB30 or OpenGL.

best regards
'Allan