** Description changed:

- Binary package hint: xserver-xorg-video-ati
+ [Justification]
+ During Intrepid development, we worked with upstream to develop two patches 
to work around banding issues on certain classes of hardware.  Upstream has 
carried on this development work and corrected several flaws that were 
subsequently found in our patches (including regression bug #274234).
  
+ [Development]
+ Upstream's git tree contains the fixes for this.  We will be pulling them in 
when we next update our git snapshot and will be included in the next -ati 
release.
+ 
+ [Patch]
+ debdiff of changes cherrypicked from upstream git is attached below.
+ 
+ [Test Case]
+ On some HD 2600 hardware, booting up into X results in an X failure with the 
following error message in Xorg.0.log:
+ (EE) RADEON(0): ParseTable said: CD_INVALID_OPCODE
+ 
+ [Regression Potential]
+ The size of this patch alone suggests that regression potential is a concern. 
 A code review did not turn up any obvious flaws, and preliminary testing by 
myself (and others who have tested snapshots of the upstream code) shows it to 
be safe.  However, I think this should be kept in -proposed for at least a 
couple weeks.  I'd like to see it tested across a wider range of ATI hardware.
+ 
+ [Original Report]
  Currently the xserver-xorg-video-ati 1:6.9.0+git20081003.f9826a56-0ubuntu2 is 
shipping two patches to workaround dithering problem on some cards. I suggest 
to update to current git version which has proper fixes for this problems:
  * RV530 on MacBook Pro
   + bug #264535
   + https://bugs.freedesktop.org/show_bug.cgi?id=17897
   + the current upstream fix has the following advantages over current ubuntu 
103_rv530_enable_diethering.patch:
    - it fixes completely the problem (the ubuntu patch still leaves some 
banding);
    - it is targetting only RV530 on MacBook Pro (where there is the dithering 
problem), not all RV530;
    - it makes the 103_rv530_enable_diethering.patch useless making the ubuntu 
packages more inline with supported upstream;
   + I tested current git version and noticed no regression so far
  * RV6xx/RV7xx cards:
   + https://bugs.freedesktop.org/show_bug.cgi?id=17094
   + current git version should also fix this problem in a similar way, though 
I don't own this hardware to test; it should have the following advantages:
    - it should fix completely the problem (the ubuntu patch appears to leave 
some banding);
    - it has a more general approach targetting not only specified cards;
    - it makes the 101_rv635_enable_dithering.patch useless making the ubuntu 
packages more inline with supported upstream;
  
  Current git version (2008-10-15 commit 
435cf7da68186f2601c4b888296117d4f652c625) has 9 commits more than current 
ubuntu version:
   - 8 commits related to the dithering problems;
   - 1 cleanup commit renaming some function;
  
  I suggest to update the ubuntu version to current git to properly fix
  the dithering problems.
  
  Test packages provided by Tormod Volden can be found at:
  https://edge.launchpad.net/~tormodvolden/+archive

-- 
Properly fix dithering problems
https://bugs.launchpad.net/bugs/284346
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