[Interest] Display color managed image

[Allan Sandfeld Jensen]

On Thursday 31 December 2015, Gunnar Roth wrote:
> Hi,
> doing my regular github scan for qml keyword,
> I just found this https://github.com/erikhvatum/StackStream
> <https://github.com/erikhvatum/StackStream>
> 
> A small collection of Qt and QML widgets for viewing images and image stack
> collections of any size + a QML scene graph plugin providing 32 bit per
> channel floating point framebuffer and layer support for optimal
> compositing, manipulation, and display of HDR and high-depth images,
> including in 30-bit mode (10 bit per channel).
> 
In Qt5.6, QPainter can internally render at 16-bits per channel, but only use 
it for the 30-bit images (10 pits per channel). I have a patch for review to 
add a native 16-bit per channel image type(see https://codereview.qt-project.org/#/c/111779/), but one of the questions that comes up is how to 
handle color-spaces.

For instance should linear color-space be a different image-type, an 
additional property on images, or a property on the paint-engine (blend in 
linear color space). The simplest seems to be to have it as an image-type as 
that image type could be blended using the existing naive blending routines, 
but should we then have linear versions of of both ARGB32 and RGBA64?, and 
should the linear versions be premultiplied or unpremultiplied 
(unpremultiplied is cheaper to color-space convert), how should QColor be 
treated, and which color-space should we assume when converting from native 
color-space to linear (sRGB or some system platform setting?). 

Lots of questions.
`Allan