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cb93df0dcb
This gets rid of virtually useless hardcoded tables hackery. The reason it is useless is that a 320 element lut is anyway placed regardless of --enable-hardcoded-tables, from which all necessary tables are trivially derived at runtime at very low cost: sample benchmark (x86-64, Haswell, GNU/Linux, single run is really what is relevant here since looping drastically changes the bench). Fluctuations are on the order of 10% for the single run test: 39400 decicycles in aacsbr_tableinit, 1 runs, 0 skips 25325 decicycles in aacsbr_tableinit, 2 runs, 0 skips 18475 decicycles in aacsbr_tableinit, 4 runs, 0 skips 15008 decicycles in aacsbr_tableinit, 8 runs, 0 skips 13016 decicycles in aacsbr_tableinit, 16 runs, 0 skips 12005 decicycles in aacsbr_tableinit, 32 runs, 0 skips 11546 decicycles in aacsbr_tableinit, 64 runs, 0 skips 11506 decicycles in aacsbr_tableinit, 128 runs, 0 skips 11500 decicycles in aacsbr_tableinit, 256 runs, 0 skips 11183 decicycles in aacsbr_tableinit, 509 runs, 3 skips Tested with FATE with/without --enable-hardcoded-tables. Reviewed-by: Rostislav Pehlivanov <atomnuker@gmail.com> Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.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 a mean to alter decoded Audio and Video through chain of 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.
- ffserver is a multimedia streaming server for live broadcasts.
- 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. Few developers
follow pull requests so they will likely be ignored.