[mythtv] MythTV 0.26, XVideo, and OpenGL

[dargllun]

On 18.04.2012 01:50, Jean-Yves Avenard wrote:
> On 18 April 2012 04:07, dargllun<dargllun at googlemail.com>  wrote:
>>
>> a) fglrx:
>> - unstable feature set
>> - flakey suspend behaviour (by itself a no-go for me)
>> - no /sys/class/drm/ interface for HDMI hotplug scripting
>> - Xv: tearing, jittery
>> - OpenGL: tearing, jittery
>
> As a side note, last week I upgraded to Ubuntu 12.04 and also tried
> the latest ATI drivers as of early April 2012.
>
> OpenGL painter with OpenGL rendering was just perfect. I had some
> tearing which disappeared after I set the "Tear-free desktop" option.
>
> I was very pleased. It worked brilliantly and the quality was as good
> as it could be (when using non-nvidia deinterlacers that is)..

Ok, so I took up the challenge and installed fglrx 12.3. Unfortunately I 
was not as pleased. BTW, for testing I usually not only play SD and HD 
material, but I always try a canned clip from some news channel which 
contains a text scroll at the bottom - the ultimate test for the 
real-time performance.

Specs:
AMD HD3200 RS780 GPU (r600),
AMD Athlon(tm) 64 X2 Dual Core Processor 5000+
FGLRX 12.3
MythTV 0.25 fixes from mythrepos as of today

In all configurations the kernel(2x) deint was used, as it gives me the 
best results while treating the CPU gently.

- Qt painter, xv-blit: nearly ok, but occasionaly hic-ups.
- Qt painter, Open-GL, tear-free off: nearly ok, but occasionaly hic-ups.
- Qt painter, Open-GL, tear-free on: good rendering, but burning CPU 
cycles as crazy. One core fully loaded. Quitting sometimes resulted in a 
frozen image and non-responding frontend, but the X session could at 
least be terminated
- OpenGL painter, Open-GL: frozen GPU, had to reboot.

So that's leading me nowhere really. Also, this GPU is rather old and I 
wouldn't be surprised if AMD stopped supporting it.

On the bright side, the OSS drivers have very much improved over the 
last years, and substantially so by AMD devs. It would be good if the 
OSS drivers would be supported by mythtv, cause they'll stay around. For 
the time being, Xv is mandatory, but perhaps OpenGL will be an option in 
the future if it's real-time performance improves. (It doesn't appear to 
be a CPU issue as Lawrence and I have observed!)

Regards
Greg