[Openicc] HP Elitebook 8540W notebook with Dreamcolor display

[Emil Briggs]

On Friday 11 February 2011 18:02:10 Kai-Uwe Behrmann wrote:
> Am 11.02.11, 17:18 -0500 schrieb Emil Briggs:
> > I very recently acquired an HP Elitebook 8540W equipped with the
> > Dreamcolor display. I'm running Linux on it and while searching for
> > software that would let me utilize the screen to it's full capabilities
> > I ran across a mention of ookala-mcf in an old thread here.
> > Unfortunately that project seems to be dead and the code threw lots of
> > errors when I tried to build it. Is anyone aware of any other Open
> > source projects that might have support for this hardware?
> 
> A actual compiling Linux version of ookala-mcf is available [1].
> 

Thanks. I grabbed a copy. It built with no issues. I tried running hpdc_util 
to see what was there and it gave me a "No displays found" message. 

i2cdetect -l shows 10 separate /dev/i2c-* nvidia entries so the kernel i2c 
support is there. I ran hpdc_util again with strace and started looking 
through the code. The devices are opened successfully but writing to them 
fails. I'm not quite sure how to proceed next. I do have the Quadro graphics 
card with the proprietary driver. Just for kicks I tried using the opensource 
nvidia driver but this does not work -- looking in the Xorg.0.log it finds the 
I2C/ddc interfaces but is unable to read any EDID information from them.

The proprietary driver does have an option to enable 30 bit color so I tried 
that. I see what you mean about the apps not being ready :)

I'm going to spend some time wrapping my head around the ookla code to see if 
I can figure out why it's not working (though I suspect that it may be related 
to the i2c kernel stuff).



> Assuming you have a inbuild Quadro graphics card, which enables this
> display to pass through 30-bit. Only the propriarity nvidia driver does
> support 30-bit on that graphics card. You distribution will typically have
> packages for that. I found the KDE desktop most useful as Qt seem 30-bit
> ready other than Gtk for the Gnome desktop. However window borders where
> not nice rendered in my tests. At the moment only OpenGL applications make
> use of that capabilities.
> 
> Btw. most open source imaging applications and games are not ready for
> 30-bit. They display simply black rectangles. This includes all Gtk based
> applications I tested, Inkscape, Gimp, CinePaint, Photoprint ...
> Instead I used a custom OpenGL image viewer for testing only.
> Blender should work and benefit from the additional precission.
> I guess you want to do imaging with the device.
> 
> To create a ICC display profile with a measuring device you might want to
> use ArgyllCMS or the GUI dispcalGUI. RPM packages are available [2]. These
> one I tested. LProf or GCM might work as well.
> 
> Without a colour measument device you can create ICC profiles on the fly
> from EDID with Oyranos. RPM packages are here [3].
> 
> If the display is a wide gamut one, the desktop might look very saturated.
> The only project which can compensate that is CompICC [4] at the cost
> that only CinePaint can currently deploy the wide gamut display. Both are
> available as RPM packages [5] and only packages from this repository
> work together.
> 
> Alternatively you can use a colour managed application in full screen
> mode. Many applciations offer that.
> 
> kind regards
> Kai-Uwe Behrmann