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Martin Mirchev
a7241b6a77
In backward mode the gain is 1 / factor, but the factor is 0 for pixels farther than dmax from the center (possible with x0/y0 or aspect), so the gain is inf. inf * sample, or inf * 0 = NaN, is then converted to int, which is undefined behaviour; on x86 these pixels come out black instead of saturated. For angles close to PI/2, the factor can also become small enough that a finite backward gain produces sample values outside the range of int before av_clip_uint8() is called. Bound the gain at 256 to keep these conversions in range while preserving the saturated 8-bit output. Signed-off-by: Martin Mirchev <mmirchev@comp.nus.edu.sg>
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 Forgejo or 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.
See https://ffmpeg.org/developer.html for more information.