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14ea4151d7
isnan and isinf are actually macros as per the standard. In particular, the existing implementation has incorrect signature. Furthermore, this results in undefined behavior for e.g double values outside float range as per the standard. This patch corrects the undefined behavior for all usage within FFmpeg. Note that long double is not handled as it is not used in FFmpeg. Furthermore, even if at some point long double gets used, it is likely not needed to modify the macro in practice for usage in FFmpeg. See below for analysis. Getting long double to work strictly per the spec is significantly harder since a long double may be an IEEE 128 bit quad (very rare), 80 bit extended precision value (on GCC/Clang), or simply double (on recent Microsoft). On the other hand, any potential future usage of long double is likely for precision (when a platform offers extra precision) and not for range, since the range anyway varies and is not as portable as IEEE 754 single/double precision. In such cases, the implicit cast to a double is well defined and isinf and isnan should work as intended. 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.