[Openicc] Questions about color pickers and graphics libraries under LINUX

[Bob Friesenhahn]

On Tue, 12 Feb 2008, Hal V. Engel wrote:

> big plus for the open source community and it shows that we can lead the way
> forward.   I don't think anyone here has much influence over what Microsoft
> or Apple will do about this issue but we can have some influence over what
> happens in the open source world.  Now we need to work with the X.Org and
> various window manager/desktop environment teams to get this issue handled on
> that level.

In my opinion, color management for the display should be handled by 
the X11 server, video device driver, and video card GPU.  The X11 
server should know the nature of the display.  Applications should 
indicate what color space the image data is in, with a default of 
sRGB.  The X11 server should arrange to display the image data 
correctly based on the nature of the display and capability of the 
video card. It does not make sense for applications to need to 
transform the pixel values before passing them on to X11.

Consider that if color management is in X11 and the interface to the 
display is 10-16 bits, then the X11 server can reasonably directly 
manage the color even if the original image is only 8 bits.  If the 
interface to the display is 8-bit, but it is possible to upload a LUT 
into the display, then the server can improve the display by uploading 
a correction LUT. Likewise, if the video card stores its images in an 
HDR format, then LDR images can be transparently converted to HDR by 
X11 (or its subordinate device driver & video card).

Bob
======================================
Bob Friesenhahn
bfriesen at simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/