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Libav
Libav is a complete, cross-platform solution to record, convert and stream audio and video. It includes an implementation of libavcodec — the leading audio/video codec library.
Software not building with Libav
Some software might not be compatible with the 0.8 or even the 0.7 Libav API.
The most outstanding issues include:
- libavutil specific function being used without including the required header:
include <libavutil/mathematics.h>
to includeav_rescale_q()
include <libavutil/avstring.h>
to include theav_str
functions
- FFmpeg only calls used:
avformat_alloc_output_context2()
might be the most used, it is a shortcut for callingavformat_alloc_context()
followed by usingav_guess_format()
and anav_strlcpy
of the filename.
Installation
USE flags
Some packages know the libav
USE flag for Preferring media-video/libav over media-video/ffmpeg whenever both are supported.
Emerge
After setting appropriate USE flags, run the emerge command:
root #
emerge --ask media-video/libav
Usage
Libav provides a new command-line tool to manipulate streams called avconv. Its aim is similar to the ffmpeg command from FFmpeg, but the syntax had been changed to be more regular and it aims to solve some long standing issues regarding time stamp guessing/generation that had been a bane for everybody trying to transcode live streams in the past.