On Friday 23 Sep 2011 21:26:56 Nikos Chantziaras wrote: > On 09/23/2011 12:54 AM, Mick wrote: > > On Thursday 22 Sep 2011 09:15:42 Nikos Chantziaras wrote: > >> On 09/22/2011 12:58 AM, Mick wrote: > >>> On Wednesday 21 Sep 2011 09:19:39 Sebastian Beßler wrote: > >>>>> Does mplayer2 work with smplayer or kmplayer? > >>>> > >>>> I use mplayer2 with smplayer for a few month now and everything works > >>>> just fine for me. > >>> > >>> Any idea when ffmpeg-mt might make it to the main portage tree? > >> > >> It's already in the tree. Both ffmpeg as well as libav now have it. > > > > Sorry I can't see a USE flag or ffmpeg-mt package in portage: > > > > $ eix -l ffmpeg | grep mt > > $ > > > > or are you saying that the code has been merged in the vanilla ffmpeg and > > libav without the need for a USE flag? > > ffmpeg-mt is not a "package". It's the name of the git branch the code > was in. That code was merged into the fmmpeg and libav projects. That > means that ffmpeg and libav now do multi-threading.
Yes, I didn't understand this initially. Thanks. :-) > Furthermore, the "threads" USE flag does *not* control this. You get > multi-threading regardless of that flag. "threads" only controls > another type of multi-threading that was there since a long time now, > but doesn't perform well. Yes, that's how I remembered this, posix compatible threads (pthreads - since 2004 or so IIRC). However, my experience with USE=threads which I just switched on to test it, is the opposite: The video rendering in mplayer is sharper and the picture therefore shows greater definition. Not much, but enough for me to notice a clearer image. The impact of threads on the CPU is not noticeable. > It would split decoding of each frame into > multiple threads, and the CPU cores would not start decoding again until > the whole frame was finished. The speed-up you get by this is minimal. > "Real" multithreading, meaning the code from the ffmpeg-mt branch > which allows every CPU core to fully decode its own video frame, cannot > be controlled by a USE flag. > > To verify if multi-threading works for you, simply play an h264 video > file in mplayer2 (using "-lavdopts threads=N", where N is the number of > CPU cores in your system) and use something like "top" or "htop" to > check CPU load of each core. I've removed USE=threads and emerged mplayer2. Multithreading works fine (5 threads are shown in top with 4 CPUs and threads=4). However, the quality of the video is inferior to vanilla mplayer and USE=threads enabled ... o_O -- Regards, Mick
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