07a11ebcab
This exploits an approach based on the sieve of Eratosthenes, a popular method for generating prime numbers. Tables are identical to previous ones. Tested with FATE with/without --enable-hardcoded-tables. Sample benchmark (Haswell, GNU/Linux+gcc): prev: 7860100 decicycles in cbrt_tableinit, 1 runs, 0 skips 7777490 decicycles in cbrt_tableinit, 2 runs, 0 skips [...] 7582339 decicycles in cbrt_tableinit, 256 runs, 0 skips 7563556 decicycles in cbrt_tableinit, 512 runs, 0 skips new: 2099480 decicycles in cbrt_tableinit, 1 runs, 0 skips 2044470 decicycles in cbrt_tableinit, 2 runs, 0 skips [...] 1796544 decicycles in cbrt_tableinit, 256 runs, 0 skips 1791631 decicycles in cbrt_tableinit, 512 runs, 0 skips Both small and large run count given as this is called once so small run count may give a better picture, small numbers are fairly consistent, and there is a consistent downward trend from small to large runs, at which point it stabilizes to a new value. Reviewed-by: Michael Niedermayer <michael@niedermayer.cc> 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.