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Andreas Rheinhardt
2d3776b8cc
This fallback function is used if external MMX is available, while inline MMX and intrinsics for emitting emms are unavailable. It is implemented as an avpriv function, which has several drawbacks for shared builds: 1. The function is so small (3 bytes; 16 with padding) that the overhead of exporting and importing it dwarfs the gains from code deduplication. 2. A call to an external library has more overhead than a library-internal one. 3. It may cause linking failures when a libavutil not exporting avpriv_emms_asm() is paired with a library needing it (if inline assembly and intrinsics were unavailable when building the dependent library). I am not aware of this ever happening. 4. We would be forced to keep avpriv_emms_asm() around for ABI stability even after it is no longer needed. This commit therefore uses the STLIBOBJS, SHLIBOBJS approach to duplicating it into each library on its own if needed. Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
FFmpeg README
FFmpeg is a collection of libraries and tools to process multimedia content such as audio, video, subtitles and related metadata.
Libraries
libavcodecprovides implementation of a wider range of codecs.libavformatimplements streaming protocols, container formats and basic I/O access.libavutilincludes hashers, decompressors and miscellaneous utility functions.libavfilterprovides means to alter decoded audio and video through a directed graph of connected filters.libavdeviceprovides an abstraction to access capture and playback devices.libswresampleimplements audio mixing and resampling routines.libswscaleimplements color conversion and scaling routines.
Tools
- ffmpeg is a command line toolbox to manipulate, convert and stream multimedia content.
- ffplay is a minimalistic multimedia player.
- ffprobe is a simple analysis tool to inspect multimedia content.
- Additional small tools such as
aviocat,ismindexandqt-faststart.
Documentation
The offline documentation is available in the doc/ directory.
The online documentation is available in the main website and in the wiki.
Examples
Coding examples are available in the doc/examples directory.
License
FFmpeg codebase is mainly LGPL-licensed with optional components licensed under GPL. Please refer to the LICENSE file for detailed information.
Contributing
Patches should be submitted to the ffmpeg-devel mailing list using
git format-patch or git send-email. Github pull requests should be
avoided because they are not part of our review process and will be ignored.