<div dir="ltr"><div><div>This code helps quite a bit. I understand how the VPP is doing the color space conversion. I also see all the other fun things the VPP code can do. </div>How do I determine which of the VPP features work for my particular HW platform? To understand what encodes and decodes are supported for a particular HW platform, I just execute: "vainfo". Is there something similar for the VPP features? How do I determine if I can do a motion adaptive deinterlace or not with a Sandy Bridge or Ivy Bridge or Haswell or whatever platform? </div>Regards, Chris </div><div class="gmail_extra"> <div class="gmail_quote">On Mon, Apr 21, 2014 at 6:43 PM, Xiang, Haihao <<a href="mailto:haihao.xiang@intel.com" target="_blank">haihao.xiang@intel.com</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div class="">On Mon, 2014-04-21 at 14:54 -0700, Chris Healy wrote: > I am working on a project that involves taking an OpenGL application > and streaming the rendered frames as H.264 wrapped in transport > stream/RTP to a multicast destination. </div>Weston has a similar feature which can use libva to encode the screen content (RGB format) in H.264, maybe you can refer to the code. <a href="http://lists.freedesktop.org/archives/wayland-devel/2013-August/010708.html" target="_blank">http://lists.freedesktop.org/archives/wayland-devel/2013-August/010708.html</a> <div class=""> > > I'm working with an i7-3517UE embedded Ivy Bridge platform running an > embedded distribution of Linux and 3.13 kernel with no display. (It's > a server on a commercial aircraft that is intended to stream a moving > map to a bunch of seatback displays.) > > I've been working to get this functionality implemented and have > gotten to the point where it works, but I have a feeling it is less > than optimal performance wise. > > At the moment, the architecture involves a patch to Mesa to do a > glreadpixels of the frame each time glxswapbuffers is called. Also in > this patch, once the glreadpixels is completed, we are using "libyuv" > to convert the RGB frame into YUY2 as we believe this is required by > libva and placing the "libyuv" converted output in a buffer that libva > can directly use. </div>For encoding, NV12 is required. The driver will convert the buffer into NV12 if the input buffer is not NV12. <div><div class="h5"> > From there on, it's pretty standard ffmpeg bits to get it on the > network. > > > The two areas I'm thinking there may be opportunity are the grabbing > of the buffer from the GPU using glreadpixels and the color space > conversion on the CPU. > > For glreadpixels, we applied a patch to Mesa to speed up the process > of moving the data by doing one large memcpy instead of a bunch of > little ones. (Patch attached.) This resulted in a much faster > glreadpixels, but none the less a halting of GPU processing while the > memory is copied using the CPU. > > For the color space conversion, libyuv does a good job of using the > SIMD instructions of the platform, but none the less, it is still > using the CPU. > > Is there a better way to get the frames from GPU memory space to > libva? Maybe something involving a zero-copy. (The application being > used is a binary that I cannot change so using special gl extensions > or making any code changes to the application is not an option. Only > changes to Mesa are possible.) > > > Is there a better way to do the color space conversion, if it is in > fact necessary? I wonder if this is something that can be done with a > Mesa patch to have a shader do the work? Would that be faster and > consume less bus bandwidth? What about libva? I see some VPP > functionality, but the fact that it is referred to as "post" > processing makes me feel that it is intended for after decoding and > not targeted at "pre" processing before an encode. Is it possible to > do the color space conversion with the libva API? > > > Any recommendations would be appreciated. > > Also, for what it's worth, I've posted the Mesa patches at the > following URLs: > > <a href="http://pastebin.com/XQS11iW4" target="_blank">http://pastebin.com/XQS11iW4</a> > <a href="http://pastebin.com/g00SHFJ1" target="_blank">http://pastebin.com/g00SHFJ1</a> > > Regards, > > Chris </div></div>> _______________________________________________ > Libva mailing list > <a href="mailto:Libva@lists.freedesktop.org">Libva@lists.freedesktop.org</a> > <a href="http://lists.freedesktop.org/mailman/listinfo/libva" target="_blank">http://lists.freedesktop.org/mailman/listinfo/libva</a> </blockquote></div> </div>