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Ganesh Ajjanagadde
e9c7493f19
This rewrites into a similar expression avoiding sqrt. Similarity is assured since sqrt(x^2 + y^2)/(x+y) lies in [1/sqrt(2), 1] for x, y > 0. Tested on x86-64, Haswell, GNU/Linux. Command: ffmpeg -f lavfi -i mandelbrot -f null - old (draw_mandelbrot): 277625266 decicycles in draw_mandelbrot, 256 runs, 0 skips 304527322 decicycles in draw_mandelbrot, 512 runs, 0 skips 377593582 decicycles in draw_mandelbrot, 1024 runs, 0 skips 338539499 decicycles in draw_mandelbrot, 2048 runs, 0 skips 583630357 decicycles in draw_mandelbrot, 4096 runs, 0 skips new (draw_mandelbrot): 274635709 decicycles in draw_mandelbrot, 256 runs, 0 skips 300287046 decicycles in draw_mandelbrot, 512 runs, 0 skips 371819935 decicycles in draw_mandelbrot, 1024 runs, 0 skips 336663765 decicycles in draw_mandelbrot, 2048 runs, 0 skips 581851016 decicycles in draw_mandelbrot, 4096 runs, 0 skips 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.