mirror of
https://git.ffmpeg.org/ffmpeg.git
synced 2026-06-16 04:32:47 +02:00
Andreas Rheinhardt
9c3f2a8894
MPEG-2 contains several elements that mustn't be zero according to the specifications: horizontal/vertical_size_value, aspect_ratio_information, frame_rate_code, the quantiser matrices, the colour_description elements, picture_coding_type, the f_code[r][s] values and quantiser_scale_code. It is now checked that the invalid values don't occur. The colour_description elements are treated specially in this regard: Given that there are files in the wild which use illegal values for the colour_description elements (some of them created by mpeg2_metadata), they will be corrected to the value meaning "unknown" (namely 2) during reading. This has been done in such a way that trace_headers will nevertheless report the original value, together with a message about the fixup. Furthermore, the trace_headers output of user_data has been beautified. Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@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.
- 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.