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Lynne
b69f65affa
Add a third context model, selected with -context 2, using only the two nearest gradients coarsely quantized, for 13 contexts per plane. Every slice starts from fresh probability states, and with many slices there is too little data per slice for the larger context sets to adapt. On a 6464x4852 16-bit RGB film scan coded with 1024 slices, this codes 87.99 MB per frame, against 90.29 MB with -context 0 and 100.79 MB with -context 1, while needing 832 bytes of probability state per slice instead of 23 KB and 324 KB. The same holds on 10-bit and 8-bit content at high slice counts; with few slices, -context 0 remains best. The table is stored in the extradata like the existing ones, so decoders need no changes.
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.