[Libva] encode surfaces created from prime fd (backed by OpenGL 2D texture)

[Víctor M. Jáquez L.]

On 05/25/16 at 01:22am, Anon wrote:
> Hi All,
> 
> I want to implement the following use case on Intel Haswell CPU with HD
> graphics:
> 
> offscreen OpenGL rendering to OpenGL 2D texture -> use
> EGL_MESA_image_dma_buf_export
> to export the texture as prime fd -> vaCreateSurfaces from the prime fd ->
> use vaapi to hw acclerate h264 encoding
> 
> Is this supported by the latest va-api and libva-intel-driver release
> (i.e., 1.7.0)? If so, is there any example I can start with?
> 
> I did read the sample application h264encode.c and thought it might be a
> good starting point. However, the first major issue I encountered is when
> creating context through vaCreateContext, a number of pre-allocated va
> surfaces are required and thus statically associated with the new va
> context. However, with prime fd, the fd will change so a new va surface is
> created with every new prime fd. I don't see any API can be used to
> dynamically add/remove va surfaces after the context is created. Can you
> please give me some suggestions?

You can look at the gstreamer-vaapi[1] code, which supports it, though right
now is under discussion and rewriting.

1. https://cgit.freedesktop.org/gstreamer/gstreamer-vaapi

vmjl