[mythtv-users] ATI AVIVO

[Michael T. Dean]

On 07/02/2006 11:38 AM, Mike Choy wrote:
> Michael T. Dean wrote:
>   
>> On 07/02/2006 02:21 AM, Mike Choy wrote:
>>> Ivan Kowalenko wrote:
>>>> On Jun 30, 2006, at 18.23, Mike Choy wrote:
>>>>>> Have enabled ATI AVIVO Support on my laptop , seems to work, has  
>>>>>> anyone
>>>>>> else got any experience, say vs XvMC.
>>>> Uhh, I'm not totally sure it's going to work. AVIVO (http://
>>>> en.wikipedia.org/wiki/AVIVO) seems to be purely software. Not sure  
>>>> there's any Linux support on that. Even if it is, I doubt you're  
>>>> going to see any improvement versus XvMC. The purpose of XvMC is to  
>>>> offload some of the MPEG-2 decoding to the GPU.
>>>>
>>>> AVIVO doesn't have a thing to do with the GPU, but relies entirely on  
>>>> the CPU for work. High-Def MPEG-2 is straining enough to the CPU, so  
>>>> I doubt you're going to see ANY improvement. Besides, AVIVO does  
>>>> ENcoding. XvMC does DEcoding.
>>> Sadly Wiki pedia is out of date.
>>> Avivo provides accelerated Video playback using the 3DGPU, for any
>>> application that uses XV and xorg 6.9 and above (standard in SUSE 10.1),
>>> which gives it huge compatability vs XvMC.
>>>
>>> http://www.phoronix.com/scan.php?page=article&item=442&num=12
>> But also means--in that mode--it's only doing the same acceleration that 
>> Xv does, but doing it with 3D hardware instead of 2D hardware.  
>> Therefore, AVIVO does not decode the stream or any part of it--it simply 
>> accelerates moving the image to the display once the CPU decodes it.  
>> Basically, it's a marketing thing to say it's there.
>>
>> If Myth wanted to use AVIVO to decode the stream, Myth would have to 
>> send the undecoded stream to the card using ATI-proprietary API's 
>> (because AVIVO itself is ATI-proprietary).  So, I don't think it will 
>> happen.
> Granted, but some quick benchmarks  of  playing back  Elephants Dream at
> 720P in mplayer show  the following, using top
>
> 1. Standard ATI XV Overlay   -average CPU utilization  show 35%-40%
> 2. Using ATI AVIVO Overlay -average CPU utilization  show 18-25%
>
> I believe that the average gains using XvMC are about 20% ?
> Of Course with an ATI card, there is no Option of XvMC.
>
> If anyone knows of a better way to benchmark this please let me know.

What video output devices on MPlayer for your two tests?

Basically, I'm just saying that if the app doesn't know that the card 
can do math for it, it obviously can't use the card to do math for it.  
I have never heard of the Xavivo standard extension for X or anything 
like it, so unless you're using MPlayer's XvMC video output device (-vo 
xvmc), I'm pretty sure the card isn't decoding anything for you.  If you 
are doing "-vo xvmc", you're just using XvMC and ATI decided to use 
their trademarked name for video stuff to indicate their support for 
XvMC--instead of explicitly saying they support the standard API.

If you're not using "-vo xvmc" (and you're not talking about a benchmark 
published by ATI which may have actually created an AVIVO video output 
device for MPlayer), something else is happening.  But, I'd need more 
info about the test to even guess what that could be.

Mike