mirror of
https://git.ffmpeg.org/ffmpeg.git
synced 2026-01-04 21:25:40 +01:00
7ece8b50b1
On 12 frames of a 444p 12 bits DNxHR sequence, _put function: C: 78902 decicycles in idct, 262071 runs, 73 skips avx: 32478 decicycles in idct, 262045 runs, 99 skips Difference between the 2: stddev: 0.39 PSNR:104.47 MAXDIFF: 2 This is unavoidable and due to the scale factors used in the x86 version, which cannot match the C ones. In addition, the trick of adding an initial bias to the input of a pass can overflow, as the input coefficients are already 15bits, which is the maximum this function can handle. Overall, however, the omse on 12 bits samples goes from 0.16916 to 0.16883. Reducing rowshift by 1 improves to 0.0908, but causes overflows. Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
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.