[vdr] vdr on PS3

Pasi Juppo pasi.juppo at iki.fi
Thu Jan 4 23:19:24 CET 2007


Matthias Schniedermeyer wrote:
> Clemens Kirchgatterer wrote:
>> Matthias Schniedermeyer <ms at citd.de> wrote:
>>
>>> I'd say the only downside of the Linux support kills it as a VDR
>>> platform. Graphic is NOT accelerated.
>>>
>>> That's the only downside i'm aware of, and i can understand Sony a
>>> little in this point. Otherwise all game developers could just skip
>>> paying licensing royalties and just develop for Linux at PS3.
>>
>> but why should this matter for multimedia (video) applications? ok, we
>> (most likely) don't have hardware accelerated xvmc, but 6 vector cores
>> to do it in software.
> 
> Video is inherently bandwith intensive.
> At least (for PAL):
> 720x576x4x25 = about 40MB/s (*)
> 1920x1080x4x25 = about 200MB/s
> 
> And that's taking aside ANY of the other processing. Decoding, IDCT,
> YUV->RGB transformation and so on. Also taking aside the total bandwith
> killer, when you have to scale the material.
> 
> AFAICT the vector cores COULD(*2) help you with the first parts, but the
> rest has to be done by the 3(,?)Ghz RISC PPC-CPU and shoveling that much
> data back and forth may be a bit much, without any acceleration.
> But on the other side the PS3 systems is supposed to have an impressing
> memory-bandwith, which could rescue the day.
> 
> So unless someone tries there is no way to be sure, but for the time
> beeing i'm sceptical.
> 
> IOW:
> - SDTV maybe
> - HDTV no way without acceleration
> 
> *:
> x4 isn't a typo. Most systems use 32 bit per color. 24 bit "packed"
> format isn't used anymore AFAIK.
> 
> *2:
> If you have software that can use the SPUs, but unless someone writes a
> Decoder-Library with SPU support you can only use the Main-CPU.

I hardly believe that PS3 would suffer at all when doing HDTV without
acceleration. There was a test several months ago of the cell processor.
It handled 48 SDTV MPEG2 streams in real time and displayed, thus scaled
down, them all at the same time on HDTV screen. I don't think hardware
acceleration is needed for x264 HDTV decoding. Only problem is the DRM
part and of course BR disc playing under Linux.


Br, Pasi



More information about the vdr mailing list