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7ec2354c38
These inline implementations of AV_COPY64, AV_SWAP64 and AV_ZERO64 are known to clobber the FPU state - which has to be restored with the 'emms' instruction afterwards. This was known and signaled with the FF_COPY_SWAP_ZERO_USES_MMX define, which calling code seems to have been supposed to check, in order to call emms_c() after using them. See 0b1972d4096df5879038f0af776f87f41e90ebd4, 29c4c0886d143790fcbeddbe40a23dfc6f56345c and df215e575850e41b19aeb1fd99e53372a6b3d537 for history on earlier fixes in the same area. However, new code can use these AV_*64() macros without knowing about the need to call emms_c(). Just get rid of these dangerous inline assembly snippets; this doesn't make any difference for 64 bit architectures anyway. Signed-off-by: Martin Storsjö <martin@martin.st>
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.