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Avconv is a very fast video and audio converter that can also grab from a live audio/video source. It can also convert between arbitrary sample rates and resize video on the fly with a high quality polyphase filter. This application now is used as replacement of FFmpeg, which means that FFmpeg seems to be deprecated.
Most of the parameters of Avconv are the same as Ffmpeg and have not difference, however, Aconv is better and more efficient application. For converting any audio/video file to another format follow the following syntax.
$ avconv -i InputFile OutputFile
As you can see, the above syntax is exactly the same as FFmpeg and has not difference at all. In Avconv by default, Mp3 encoder is not installed which means that if you want to convert any file to Mp3 or vice versa the application displays the following error to you.
Encoder (codec id 0) not found for output stream #0:0
For overcoming to above issue, you need to install “libavcodec-extra-53” package. On Debian based Linux, you can use the below command to install the package.
$ sudo apt-get install libavcodec-extra-53
Finally, if you want to convert bunch of files together to another format such as converting all .Flv files to .Mp3, the below command could be really useful.
$ for i in *.flv; do avconv -i "${i}" "${i%.flv}.mp3"; done
Above line is created from mixture of Avconv application and bash script command. In fact it is a simple for loop which converts all .flv to .mp3.
For more information about Avconv refer to its manual page and for learning bash script click on following link,
