On 2016/8/16 10:14, Chao Liu wrote: > On Mon, Aug 15, 2016 at 6:00 PM, Jun Zhao <mypopy...@gmail.com> wrote: > >> >> >> On 2016/8/16 1:48, Jean-Baptiste Kempf wrote: >>> On 15 Aug, Hendrik Leppkes wrote : >>>>> On Mon, Aug 15, 2016 at 10:22 AM, Jun Zhao <mypopy...@gmail.com> >> wrote: >>>>>>> add libyami decoder/encoder/vpp in ffmpeg, about build step, >>>>>>> please refer to the link: https://github.com/01org/ >> ffmpeg_libyami/wiki/Build >>>>>>> >>>>> >>>>> We've had patches for yami before, and they were not applied because >>>>> many developers did not agree with adding more wrappers for the same >>>>> hardware decoders which we already support. >>>>> Please refer to the discussion in this thread: >>>>> https://ffmpeg.org/pipermail/ffmpeg-devel/2015-January/167388.html >>>>> >>>>> The concerns and reasons brought up there should not really have >> changed. >>> I still object very strongly against yami. >>> >>> It is a library that does not bring much that we could not do ourselves, >>> it duplicates a lot of our code, it is the wrong level of abstraction >>> for libavcodec, it is using a bad license and there is no guarantee of >>> maintainership in the future. >> >> I know the worry after read the above thread.For Intel GPU HW accelerate >> decode/encode, >> now have 3 options in ffmpeg: >> >> 1. ffmpeg and QSV (Media SDK) >> 2. ffmpeg vaapi hw accelerate decoder/native vaapi encoder >> 3. ffmpeg and libyami >> > Sorry for this little diversion: what are the differences between QSV and > vaapi? > My understanding is that QSV has better performance, while vaapi supports > more decoders / encoders. Is that correct? > It would be nice if there are some data showing the speed of these HW > accelerated decoders / encoders.
QSV has better performance is right, but libyami have more decoders/encoders than vaapi hw accel decoder/encoder. :) According our profile, the speed of QSV/Libyami/vaapi-hw accel decoder and native vaapi encoder are: QSV > ffmpeg and libyami > vaapi-hw accel decoder and native vaapi encoder > >> >> And I know the guys prefer option 2 than 3, but I have a little question, >> what's the >> difference about ffmpeg/libyami and the other external codec library(e,g >> openh264, >> videotoolbox...)? >> > Is 2 available in ffmpeg today or is it sth. planned? > Option 2 is available today :), I think the wiki page ( https://wiki.libav.org/Hardware/vaapi) is good refer to for option 2, if you want to try. :) >> >> As I know Intel have 3 full time Libyami developers, so no guarantee maybe >> is wrong.:) >> >> Tks. >> _______________________________________________ >> ffmpeg-devel mailing list >> ffmpeg-devel@ffmpeg.org >> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel >> > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > http://ffmpeg.org/mailman/listinfo/ffmpeg-devel > _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
