On VAAPI vs libx264

[Víctor M. Jáquez L.]

On 07/22/16 at 02:43am, Ezequiel Garcia wrote:
> Currently, I am using libx264 to encode analog videos on a video server product.
> I'm near the CPU limit, so I was considering switching to vaapi-based encoding.
> My initial experiments were *very* promising, as my CPU went down like a sack
> of potatoes
> 
> The only issue I found so far is that file size is greatly increased
> (around 4 times bigger!), yet I'm unable to tune vaapih264enc
> to match libx264.

Sree can give more details about this than me, but as far as I know,
gstreamer-vaapi generates a lot of I frames with small GOP and that is because
on how gstreamer-vaapi encoders were written originally.

But Sree right now  is working to improve this.

vmjl

> 
> Before I start diving into the encoder internals, I was wondering:
> 
> Is this an intrinsic limitaion of the hardware encoder, or should
> I dig into libva parameters? For example, I haven't found a way to
> change the GOP size to improve compression (while keeping quality).
> 
> Maybe we need to add extra knobs in the gstreamer frontend?
> 
> Thanks!