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Niklas HaasandClaude Opus 5.5
0e49820959
Previously, the uop macros were generated from the union of uops over all backends, so each backend would also instantiate uops that only the other one can ever use. Split off a separate "x86" backend, and generate a separate C header for it, together with its NASM macros in a single pass. The x86 backend only enables SWS_UOP_FLAG_FMA on CPUs with FMA3, so generate its uops both with and without FMA. This does not reduce the checkasm coverage: the uops removed from uops_macros.h are all LINEAR_FMA, READ_PLANAR_FV_FMA or RW_SHUFFLE, which checkasm does not test, since the C reference backend cannot run them. The only tests that disappear are the SSE4 and AVX2 variants of two U8 PERMUTE kernels, which the x86 backend no longer builds because it never uses them. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Signed-off-by: Niklas Haas <git@haasn.dev>
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 Forgejo or 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.
See https://ffmpeg.org/developer.html for more information.