On VAAPI vs libx264
Locked
 
|
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. 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! -- Ezequiel García, VanguardiaSur www.vanguardiasur.com.ar _______________________________________________ gstreamer-devel mailing list [hidden email] https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel |
|
|
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! gstreamer-devel mailing list [hidden email] https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel |
|
|
On Fri, Jul 22, 2016 at 10:31 AM, Víctor M. Jáquez L. <[hidden email]> wrote: On 07/22/16 at 02:43am, Ezequiel Garcia wrote: Unfortunately We don't have rich set of tuning options like x264 , but we will improve this in future. For GOP adjustments, currently we only have "max-bframes" property.You might have already experimented with it :) There are few options to reduce the file size, -- enable cabac (no need if you are using git master of gstreamer-vaapi where cabac enabled by default) -- increase max-bframes value -- increase the init-qp value Some works to add hierachical encode is on going: https://cgit.freedesktop.org/~sree/gstreamer-vaapi/log/?h=svc
Regards,
Sreerenj Balachandran Intel Open Source Technology Center _______________________________________________ gstreamer-devel mailing list [hidden email] https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel |
|
|
On 22 July 2016 at 07:50, Sreerenj Balachandran <[hidden email]> wrote:
> > > On Fri, Jul 22, 2016 at 10:31 AM, Víctor M. Jáquez L. <[hidden email]> > wrote: >> >> 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. > > Unfortunately We don't have rich set of tuning options like x264 , but we > will improve this in future. > > For GOP adjustments, currently we only have "max-bframes" property.You might > have already experimented with it :) > > There are few options to reduce the file size, > -- enable cabac (no need if you are using git master of gstreamer-vaapi > where cabac enabled by default) > -- increase max-bframes value > -- increase the init-qp value > > Some works to add hierachical encode is on going: > https://cgit.freedesktop.org/~sree/gstreamer-vaapi/log/?h=svc > Hi guys, Thanks for the reply! So, just to clarify: this limitation is in the gstreamer plugin, not in the vaapi encoder per se? The distinction is important for me as it's the difference between dropping this effort, or putting it on hold until this is fixed/improved. -- Ezequiel García, VanguardiaSur www.vanguardiasur.com.ar _______________________________________________ gstreamer-devel mailing list [hidden email] https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel |
«
Return to GStreamer-devel
|
1 view|%1 views
| Free forum by Nabble | Edit this page |