On Wed, Jan 20, 2016 at 12:13 PM, Andy Furniss <adf.li...@gmail.com> wrote: > wm4 wrote: >> >> On Wed, 20 Jan 2016 09:59:12 +0000 Andy Furniss <adf.li...@gmail.com> >> wrote: >> >>> wm4 wrote: >>>> >>>> On Wed, 20 Jan 2016 00:42:18 +0000 Andy Furniss >>>> <adf.li...@gmail.com> wrote: >>>> >>>>> Hendrik Leppkes wrote: >>>>> >>>>>>>> I do not agree that it should be a warning. As outlined >>>>>>>> in the commit message and this thread, there are serious >>>>>>>> flaws with frame threading and hwaccel. >>>>>>> >>>>>>> >>>>>>> I'm fine with it being an error, but since it is an API >>>>>>> change, it should follow the usual deprecation period to >>>>>>> allow downstream users time to fix it. Meanwhile it can be >>>>>>> a warning so that people notice the problem. >>>>>> >>>>>> >>>>>> Its fundamentally broken, and making it a warning would >>>>>> re-introduce known crashes. So no. >>>>> >>>>> >>>>> So are the flaws in ffmpeg or particular drivers? >>>>> >>>>> It does seem a shame perf wise, I've been testing my AMD UVD >>>>> decode recently and for 500 UHD frames in a really high >>>>> bitrate h264 file it's like - >>>>> >>>>> ffmpeg threaded = 16 sec. >>>>> >>>>> ffmpeg single thread = 20 sec. >>>> >>>> >>>> With or without hwaccel? >>> >>> >>> Both are with hwaccel. ffmpeg 2.8.4 cli >>> >>> Admittedly a very concocted benchmark with a very high bitrate >>> sample. >>> >>> I know on normal x264 stuff my CPU could beat GPU anyway as the >>> copy back seems to hurt quite a lot/UVD is for playing. >>> >>> For future GPUs that will do hevc I guess it could be more >>> relevant. >>> >>>>> gstreamer vaapi 14 sec. >>>>> >>>>> gstreamer omx 10 sec. >>>>> >>>>> the omx is a faster as the others do nv12 -> I420 on cpu >>>>> (AFAICT) >>>>> >>>>> Maybe -threads 1 hurts perf by limiting the format conversion >>>>> as well? >>>>> >>>>> Is there a way to get whatever the h/w spits out (nv12) >>>>> directly? Trying to ask for nv12 seemed to get a double >>>>> conversion. >>>> >>>> >>>> Both vdpau and vaapi can retrieve image data as nv12. >>> >>> >>> With ffmpeg cli? >> >> >> ffmpeg cli doesn't support vaapi. > > > I know, but it does do vdpau: so to restate my question in a clearer way - > > Is it possible with ffmpeg cli -hwaccel vdpau to avoid nv12 -> I420 > conversion? > >> With what hardware was this? What were the command lines you used? > > > GPU is AMD R9285 TONGA (drivers are still new/experemental) but results > for this test seem consistent. > > Rest of system is older Phenom II x4 3.4GHz (cpufreq forced for tests). > Mobo is PCIE 2.0 *Gig ram @ 1333. > > Here's a paste I made a few days ago - includes s/w test (which by > chance for this sample comes out the same as multithread h/w) You can > see from the time cpu use output I really do get h/w decode as requested.
If you would run with verbose logging (-loglevel verbose), you would get information which format the vdpau code uses to retrieve the data, as well as clear confirmation that it uses hwaccel. _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
