[vlc-devel] DXVA : workaround for a bug in ATI drivers

Laurent Aimar fenrir at via.ecp.fr
Wed Jan 6 21:08:00 CET 2010


On Tue, Dec 29, 2009, Mathieu Velten wrote:
> I am a hacker on the directshow player MPC-HC. I just see that you add
> hardware acceleration (great work !).
> I read the code and it seems that you are not aware of a DXVA
> implementation bug in ATI driver :
> the ATI driver needs the scaling matrix in raster order (vs zigzag
> order in the standard).
> You should change the fill_scaling_lists function accordingly in the
> ffmpeg dxva2 patch using the "workaround" field of the context I
> guess.
> this bug should only trigger with files using custom matrices since a
> flat matrix is the same with both orders.
 Thanks for the report and especially for the detection code :)
 As I don't have an ATI card, I didn't try to workaround this bug, but it
will be trivial to do it at the ffmpeg level (using the workaround field
as you noticed).

 When I find a bit of time, I will come up with a patch.


More information about the vlc-devel mailing list