Hi, 2015-10-12 20:10 GMT+02:00 Stefano Sabatini <stefa...@gmail.com>: > Hi all, > > I wanted to test QSV encoding and decoding, which is included since > several months in FFmpeg, and have a few questions. > > 1. QSV encoding and decoding depends on libmfx, but no references are > present in the code to the library, so I have to suppose that the > required library is this one: > https://github.com/lu-zero/mfx_dispatch
Luca's repo is indeed what allows it to build effortlessly, while also supplying a DSO for libmfx. It is also possible to build against the Intel supplied headers but a correct pkg-config file is indeed missing, and additional configury would be needed in the FFmpeg part to use the libs.private portions of it. i.e. in case we are stuck to a static library. FFmpeg should also provide an explicit link to libva-drm, since it uses it in the MFX specific parts. > While at it, do you know what's the point of the mfx_dispatch > component (why adding the intel media library path to flags is not > enough)? Probably to select between the SW and HW implementations. :) > 2. The mfx_dispatch library compiles fine on my system, but then I > wonder how it is supposed to reference the Intel Media library: > https://software.intel.com/en-us/intel-media-server-studio IIRC, there is an installation script in the Media Server Studio. However, I didn't use it but rather used the "Generic" variant and installed everything into a dedicated subdirectory. > > ... > > I'm able to compile FFmpeg with --enable-libmfx after installing > the mfx_dispatch library, and run this command: > ffmpeg -i test.mp4 -c:v h264_qsv -y test.out.mp4 > > but then it fails with: > Error initializing an internal MFX session > > Running strace on the command it results that it's looking for the > libmfxsw64.so library and failing: > open("/lib/x86_64-linux-gnu/libmfxsw64.so", O_RDONLY|O_CLOEXEC) = -1 ENOENT > (No such file or directory) > open("/usr/lib/x86_64-linux-gnu/libmfxsw64.so", O_RDONLY|O_CLOEXEC) = -1 > ENOENT (No such file or directory) > open("/lib/libmfxsw64.so", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or > directory) > open("/usr/lib/libmfxsw64.so", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file > or directory) > munmap(0x7f9a55072000, 155122) = 0 > > If I update the LD_LIBRARY_PATH to point to the intel media library in > /opt/intel/mediasdk it will find the library and then hang. > > I had some hard time finding relevant information on the Internet, so > I ask if you can help to clarify these points. > > I'll happily provide a few benchmarks and update documentation > accordingly if I manage to make it work. > -- > FFmpeg = Fancy and Forgiving Mean Problematic Excellent Gymnast > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > http://ffmpeg.org/mailman/listinfo/ffmpeg-devel Regards, -- Gwenole Beauchesne Intel Corporation SAS / 2 rue de Paris, 92196 Meudon Cedex, France Registration Number (RCS): Nanterre B 302 456 199 _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
