On Sun, 11 Feb 2007 16:16:32 +0000
Dieter <[EMAIL PROTECTED]> wrote:
> > In regard of OGP? Just a framebuffer. Everything else can be done
> > in software.
>
> This has been discussed before. CPUs aren't fast enough (see the archives
> for examples). Therefore we MUST have some sort of hardware assist.
Actualy no. MPEG1/2/4 is more than fast enough in software.
The problem is the I/O involved and the missdesign of most
video player that do not use DMA. h.264 is another matter and
yes, there you can get into the situation that your CPU is
not fast enough when all features are enabled. But, then
OGA will be even slower. Please remember that h.264 is a
total bitch when it comes to decoding. It wasn't designed
with easy hardware implementation in mind but with
software implementation. Unlike with MPEG1/2 and to
some big extend MPEG4, h.264 isn't stream based, but
uses (optional) features that work on large areas of
the image. This translates to memory access patterns
that are hardly cachable and not streamable at all.
If you really think about implementing a h.264 decoder
in hardware, then you need to put another spartan3 onto
the board as there wont be much space left for anything else.
> > And i clearly vote against it. OGD1 wont have enough
> > real estate to implement a full MPEG2 decoder
>
> OGD1 is one thing, but OGC needs mpeg decoding or why bother?
> We already have hw that can't do video, don't need another.
Why should it need mpeg decoding in hw? I know very few
hw decoder cards that are still sold. All hardware solutions
for decoding of video sold these days are made for set top boxes
which require a completely different set of features and
interfaces. I doubt that OGC will be any use in this market,
especialy as it is already split up between a few big players.
> Undocumented hw features aren't very useful.
> Documented hw that doesn't do what you need isn't very useful.
> We need both the feature and the documentation.
First we need something that works at all.
Attila Kinali
--
Lotus Notes ist eine verteilte Datenbankapplikation,
als Sample ist eine miese Groupware dabei ;)
-- Lukas Beeler
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