mirror of
https://github.com/FFmpeg/FFmpeg.git
synced 2025-03-28 12:32:17 +02:00
d85c6aba0c
Stop using InputStream.dts for generating missing timestamps for decoded frames, because it contains pre-decoding timestamps and there may be arbitrary amount of delay between input packets and output frames (e.g. dependent on the thread count when frame threading is used). It is also in AV_TIME_BASE (i.e. microseconds), which may introduce unnecessary rounding issues. New code maintains a timebase that is the inverse of the LCM of all the samplerates seen so far, and thus can accurately represent every audio sample. This timebase is used to generate missing timestamps after decoding. Changes the result of the following FATE tests * pcm_dvd-16-5.1-96000 * lavf-smjpeg * adpcm-ima-smjpeg In all of these the timestamps now better correspond to actual frame durations.
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.