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Libav

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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 include av_rescale_q()
include <libavutil/avstring.h> to include the av_str functions
  • FFmpeg only calls used:
avformat_alloc_output_context2() might be the most used, it is a shortcut for calling avformat_alloc_context() followed by using av_guess_format() and an av_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.

Cannot load package information. Is the atom media-video/libav correct?

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.

See also

External resources