[openchrome-devel] [Bug 101395] Color banding with OpenChrome driver V0.6.133

[bugzilla-daemon]

https://bugs.freedesktop.org/show_bug.cgi?id=101395

GitLab Migration User  changed:

   What|Removed |Added

 Status|NEW |RESOLVED
 Resolution|--- |MOVED

--- Comment #8 from GitLab Migration User  ---
-- GitLab Migration Automatic Message --

This bug has been migrated to freedesktop.org's GitLab instance and has been
closed from further activity.

You can subscribe and participate further through the new bug through this link
to our GitLab instance:
https://gitlab.freedesktop.org/openchrome/old-bug-database/issues/22.

-- 
You are receiving this mail because:
You are on the CC list for the bug.___
openchrome-devel mailing list
openchrome-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/openchrome-devel

[Openchrome-devel] [Bug 101395] Color banding with OpenChrome driver V0.6.133

[bugzilla-daemon]

https://bugs.freedesktop.org/show_bug.cgi?id=101395

--- Comment #7 from Kevin Brace  ---
Hi Marty,

Give me several weeks for me to figure out what to do about this problem.
In the meantime, I will continue to work on fixing other OpenChrome DDX issues,
and develop the next generation OpenChrome DRM by importing code from
OpenChrome DDX.

-- 
You are receiving this mail because:
You are on the CC list for the bug.___
Openchrome-devel mailing list
Openchrome-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/openchrome-devel

[Openchrome-devel] [Bug 101395] Color banding with OpenChrome driver V0.6.133

[bugzilla-daemon]

https://bugs.freedesktop.org/show_bug.cgi?id=101395

--- Comment #6 from Marty  ---
Hi Kevin,

Here are the results of my tests:

1. With LAPTOP ALONE I get ALWAYS color banding. Already with the log-in screen
and also after log-in.

2. When I start the laptop alone but attach a CRT after the log-in I get color
bands on the laptop LCD and at the same time NO color bands on the CRT. When I
now lock the computer and go back to the log-in screen, both, the LCD and the
CRT, show NO color bands! But when I log-in again it goes back to the behaviour
before: color bands on the LCD, no color bands on the CRT.

3. When I connect the CRT right from the beginning (that means I boot the
laptop with attached CRT) I NEVER get color banding! Everything is always
smooth, on the LCD and CRT. Furthermore: When I disconnect the CRT after
booting and log-in, the laptop LCD still remains without color banding!

I hope this anyhow says something to you...

Regards,
Marty

-- 
You are receiving this mail because:
You are on the CC list for the bug.___
Openchrome-devel mailing list
Openchrome-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/openchrome-devel

[Openchrome-devel] [Bug 101395] Color banding with OpenChrome driver V0.6.133

[bugzilla-daemon]

https://bugs.freedesktop.org/show_bug.cgi?id=101395

--- Comment #4 from Kevin Brace  ---
(In reply to Marty from comment #3)

Hi Marty,

> Hi Kevin,
> 
> Yes. This is exactly what I see! I even downloaded from Internet the
> original Lubuntu 12.04 wallpaper to do a closer analysis of the number of
> color steps in the image. It is identical to what you uploaded. So I can say
> everything looks like being in a 16 bit color mode.
> 
> Cheers,
> Marty

Okay, at least for 16-bit color mode, I have known this issue for a while, but
there are reasons why I had to live with this flaw for OpenChrome DDX Version
0.6.
Prior to OpenChrome DDX Version 0.5 or 0.6, 16-bit color mode was broken if
gamma correction hardware was turned on.
Turning on gamma correction was the reason why the colors went nuts in 16-bit
mode, so I had to turn it off.
16-bit color mode is still useful in some cases, especially one wants to use
dual head mode with left and right screen (As I have discussed previously, due
to hardware limitations, you will need to use 16-bit color mode if one wants to
use 2 monitors side by side.).
At the end of the day, since I am the only one who gets to decide what goes
into the code (because I am pretty much the only person on this planet that
spends so much time in trying revive old, abandoned graphics device drivers), I
had to make tradeoffs, and since there had to be a new version of OpenChrome
released at some point, I had to ship a new version with this color gradient
flaw.
My goal of OpenChrome development has always been to improve the quality of the
code since Day One (sometime around mid-2015), and as far as I am concerned,
the code is gradually getting to where it should be (i.e., The latest
improvement in how display devices are detected which fixed the standby resume
issue with your laptop's 24-bit FP interface to a VIA LVDS bridge chip.).
Like the previous bug I have effectively fixed (i.e., standby resume 24-bit
FP interface FP restoration bug), it might take a while for me to figure out
how to fix the problem.
Since I practically do not use Lubuntu 14.04 at all, if you do not mind keeping
Lubuntu 12.04 for now (until I fix the bug), that will be appreciated.
That being said, I tried the 16-bit color mode on Xubuntu 14.04 yesterday, and
I did observe the same color gradient issue I saw on Lubuntu 12.04.
I will revisit what I did with the color palette and gamma control many months
ago.
I think it will take a while to fix this issue, and I will also have to
continue to devote some time to modernize the current OpenChrome DDX code so
the code developed for OpenChrome DDX can be effectively shared with OpenChrome
DRM.

-- 
You are receiving this mail because:
You are on the CC list for the bug.___
Openchrome-devel mailing list
Openchrome-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/openchrome-devel

[Openchrome-devel] [Bug 101395] Color banding with OpenChrome driver V0.6.133

[bugzilla-daemon]

https://bugs.freedesktop.org/show_bug.cgi?id=101395

--- Comment #3 from Marty  ---
Hi Kevin,

Yes. This is exactly what I see! I even downloaded from Internet the original
Lubuntu 12.04 wallpaper to do a closer analysis of the number of color steps in
the image. It is identical to what you uploaded. So I can say everything looks
like being in a 16 bit color mode.

Cheers,
Marty

-- 
You are receiving this mail because:
You are on the CC list for the bug.___
Openchrome-devel mailing list
Openchrome-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/openchrome-devel

[Openchrome-devel] [Bug 101395] Color banding with OpenChrome driver V0.6.133

[bugzilla-daemon]

https://bugs.freedesktop.org/show_bug.cgi?id=101395

--- Comment #2 from Kevin Brace  ---
Hi Marty,

Does the screen you are describing look like the screenshot I just uploaded?
Note that this screenshot was taken in 16-bit color mode.
I do not see this in 32-bit color mode.

-- 
You are receiving this mail because:
You are on the CC list for the bug.___
Openchrome-devel mailing list
Openchrome-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/openchrome-devel

[Openchrome-devel] [Bug 101395] Color banding with OpenChrome driver V0.6.133

[bugzilla-daemon]

https://bugs.freedesktop.org/show_bug.cgi?id=101395

--- Comment #1 from Kevin Brace  ---
Created attachment 131962
  --> https://bugs.freedesktop.org/attachment.cgi?id=131962=edit
Lubuntu 12.04 16-bit color desktop

This is from Lubuntu 12.04 16-bit color desktop.

-- 
You are receiving this mail because:
You are on the CC list for the bug.___
Openchrome-devel mailing list
Openchrome-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/openchrome-devel

[Openchrome-devel] [Bug 101395] Color banding with OpenChrome driver V0.6.133

[bugzilla-daemon]

https://bugs.freedesktop.org/show_bug.cgi?id=101395

Kevin Brace  changed:

   What|Removed |Added

 CC||openchrome-de...@lists.free
   ||desktop.org

-- 
You are receiving this mail because:
You are the assignee for the bug.
You are on the CC list for the bug.___
Openchrome-devel mailing list
Openchrome-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/openchrome-devel