RFC: Video decode acceleration API

[Bian, Jonathan]

A lot of current (and future) graphics chipsets (discrete or integrated)
have fixed function pipelines for video decode.  Lack of a common
acceleration interface makes it difficult for applications to take
advantage of these capabilities in the hardware and that is what this
proposal attempts to solve. 

Jonathan Bian

-----Original Message-----
From: stephane.marchesin at gmail.com [mailto:stephane.marchesin at gmail.com]
On Behalf Of Stephane Marchesin
Sent: Wednesday, March 28, 2007 12:17 PM
To: Roderick Colenbrander
Cc: Bian, Jonathan; xorg at lists.freedesktop.org; Donlon, Mike
Subject: Re: RFC: Video decode acceleration API

On 3/28/07, Roderick Colenbrander <thunderbird2k at gmx.net> wrote:
> I wonder if we need a new extension at all. Modern videocards from
ati/nvidia/s3 and perhaps intel too which support formats like mpeg4,
vc-1 and others all utilize the fragment shader engine of the gpu. They
don't have dedicated decoding hardware for specific compression schemes.
Perhaps it is a smarter idea to implement such a library using lets say
GLSL. You could have code which works on all cards with fragment shader
support. (For modern card this is being worked on).
>

Yes, I pretty much agree on that idea, except that as Alex says, older
cards aren't supported.

I had the idea the other day that we could write common OpenGL video
decoding code (inside glucose maybe) that implements whatever new API,
and have all the cards with shader support benefit from the nice
hardware video decoding.

That wouldn't prevent older cards from having their own stuff for
video decoding, but at the same time allows recent cards to get video
decoding support at very small cost.

Stephane