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Rework the code a bit to speed up the 10-bit bitpacked decoding routine. This is probably about as fast as I can get it without switching to assembly language. Demonstratable with: ./ffmpeg -f lavfi -i "smptehdbars=size=3840x2160" -c bitpacked -f image2 -frames:v 1 source.yuv ./ffmpeg -f bitpacked -pix_fmt yuv422p10le -s 3840x2160 -c:v bitpacked -i source.yuv -pix_fmt yuv422p10le out.yuv On my development system, it went from 80ms for a 2160p frame down to 20ms (i.e. a 4X speedup). Good enough for now, I hope... Comments from Marton: Originally on my system better performance could be achieved by simply switching to the cached bitstream reader, but for Devin it was slower than his direct byte operations. I changed the order of writing output from u/y/v/y to u/v/y/y, and that made the code faster than the cached bitstream reader on my system as well. TIMER measurement of the decode loop on Ryzen 5 3600 with command line: ./ffmpeg -stream_loop 256 -threads 1 -f bitpacked -pix_fmt yuv422p10le -s 3840x2160 -c:v bitpacked -i source.yuv -pix_fmt yuv422p10le -f null none -loglevel error Before: 823204127 decicycles in YUV, 256 runs, 0 skips After: 315070524 decicycles in YUV, 256 runs, 0 skips Signed-off-by: Devin Heitmueller <dheitmueller@ltnglobal.com> Signed-off-by: Marton Balint <cus@passwd.hu>
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.