poor video playback performace with radeon

Alex Deucher alexdeucher at gmail.com
Wed Aug 17 13:40:05 PDT 2011

On Wed, Aug 17, 2011 at 4:36 PM, Taneli Vähäkangas
<taneli.vahakangas at cs.helsinki.fi> wrote:
> On Wed, Aug 10, 2011 at 09:57:06AM -0400, Alex Deucher wrote:
>> Yes, src/gallium/auxiliary/vl is the location of the code.  It
>> currently supports XvMC and VDPAU for mpeg1/2.
> I see. It works, but the output is quite buggy, and features are
> missing. Is this to be expected?

Yes, it's still a work in process.

> I think something goes wrong when decoding macroblocks in P and B
> frames. Intra macroblocks and thus I frames are correct. The
> "dimming" of the image over time (with even zero motion vectors)
> might be explained by predictors being discarded at wrong spots,
> but I could not find fault in the code. I have no clue yet as to
> what might cause every second line to be dark, but am looking at
> frame/field and 4:2:0 and 4:2:2 differences.

There are known issues with interlaces videos.

> However, debugging is really slow. My current workflow is to plug
> my changes to the xorg-edgers mesa source packages and build the
> binaries again. This takes about 70 minutes, and requires X
> restart. There must be a faster/more convenient way (especially
> since my changes end up only in libgallium, not other dlls), how do
> other people hack this part of the tree?

Easiest is to checkout the mesa git tree and build/install mesa from
there.  Then when you make changes, all you need to do is rebuild and
install, no restart required.


> Cheers,
>        Taneli

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