Re: [Gnash-dev] Hardware acceleration support

[Craig Kelley]

On Mon, 1 Mar 2010, Rob Savoye wrote:

> If anyone decides to play with this, run 'gnash --render-mode
> (opengl|cairo|agg)'. The new option for HW video accelerators is
> '--hwaccel (none, vaapi, xv)'. So far I've tested this on an Nvidia
> (binary blob and libvdpau required), and Intel (965 required), and
> supposedly ATI works with libxvba.

Awesome!

> The last thing I need to fix before migrating this to trunk is currently
> if vaapi is enabled, but you don't have supported hardware, it doesn't
> handle this gracefully at all. (it segfaults, actually) it should also
> be possible to find the best defaults for a platform, for example
> testing for opengl/vaapi support, then dropping back to agg/vaapi, then
> agg/xv, then agg/none. Unfortunately Gnash's Xv support has a major
> scaling bug...

It depends on what you indend and what it actually does.  What behavior 
are you seeing?

> So far I actually haven't seen much performance improvement in my
> testing, (mpeg4 n an FLV) but it looks like the bottleneck is in our
> renderers.

Full-screen FLV is pretty much the only thing that benefits from it, 
although things like animations can as well.  If you tell the renderer to 
render something like Strongbad at 640x480, and then have Xv blow it up to 
1900x1200, it works flawlessly -- if you have AGG render directly to 
1900x1200, then Xv doesn't help at all, and chances are you're seeing 1 
frame every 5 seconds from AGG.

It's confusing...  Adobe have tackled this by only using hw acceleration 
to blow up full-screen movies.

--
Craig Kelley
http://inconnu.islug.org/~ink finger same server for PGP block