Matthias Schniedermeyer wrote:
Darren Wilkinson wrote:
Matthias Schniedermeyer wrote:
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.
Bis denn
Most people AFAICT use vdr for sdtv and while HDTV may or may not be out
of the question due to bandwidth sdtv definitely isn't. In fact I have
linux on my xbox which has much less bandwidth than even the ps2 and
most distros for that have a dvd player.
The thing with the XBOX is that it pretty much has a standard PC with a
standard Geforce 3.5 (AFAIR it is something between the 3 and the 4). So
it should have hardware acceleration, which makes it a quite good
platform for a video player, although i wouldn't buy one myself.
The xbox does have the hardware but (like the PS3) has no accelerated
drivers to use it. Video access is done through the framebuffer but this
is more than enough for dvd playback which is the same resolution as sdtv.
I am actually looking into a building a working dtv rig for the
(original) xbox but am much more limited by the "mere" 60mb (64mb-4mb
for the framebuffer) of memory and others have made mythtv clients for
it. As someone else pointed out though a PS3 for linux doesn't make much
sense unless you already want a PS3. Any applications it runs will, due
to the 88mb ram, probably *feel* slower than a 1-2ghz pc with 128mb+ of
ram running an quivalent distro even without graphics accelleration.
If i'm not mistaken you mixed it with the memory that the Wii has.
The PS3 and the XBox360 have 512MB total. And i'm quite sure that one of
them was a split-memory-architecture (256MB/256MB) and the other one has
a unified-memory-architecture.
So the PS3 should have something around 240MB or 500MB of available memory.
Yep, my bad.
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