Software for converting various multimedia file formats?

Searching the Ubuntu Software Center reveals several GUI options:

• Transmageddon - Very simple interface for individual files, supports audio and video.
• OggConvert - Transcode multimedia into open formats.
• Artista Transcoder - Primarily intended for transcoding videos into formats recognized by portable players (which you can select from a list).
• Sound Converter - My favorite for transcoding mp3s and other audio files. Takes in whole folders, exactly what you need!

ffmpeg can do pretty much any media conversion. As an example, use this to extract an MP3 from a FLV video: ffmpeg -i $1 -f mp3 -ab 128000 $2 where $1 and $2 are the source and target filenames.

There is also a GUI available called WinFF which reduces the amount of command-line-fu required.

First make sure you have installed the 'restricted" packages ( ubuntu-restricted-extras). this way you will have all the taggers, encoders and decoders on your system. Then use any of the above gui tool. Then use Sound Converter for audio and Transmaggedon fo Video.

Apart from such programs as transmageddon, there is a python based program in development called curlew that has a simple interface, but allows you to convert between many formats using ffmpeg or libav-tools. It has been mentioned in this article recently, but some additional points need to be noted about installation, use, and removal of the tool.

As noted at github, there are several dependencies that need to be installed, though you will already have python and xdg-utils:

sudo apt-get install git libavcodec-extra-53 mencoder xdg-utils python python-gobject gir1.2-gtk-3.0 ffmpeg

It supports either ffmpeg or libav-tools, so you can put either in the command above, although ffmpeg has been deprecated in favour of libav-tools in Ubuntu.

Installation is straightforward (the first cd is to make sure you are at the top level of your home folder):

cd 
git clone git://github.com/chamfay/Curlew.git
cd Curlew
sudo ./install

You should keep the Curlew folder, as you can uninstall it properly by running sudo ./uninstall from that folder.

Then, just selecting curlew from the programs menu (multimedia) or entering in terminal curlew & will launch the program.

Additional Note:

If for any reason you have compiled ffmpeg or libav (as I have done), and now the key encoders/decoders are in the /usr/local hierarchy, you will need to run the program with a wrapper script or it will not find the libraries.

(Only use this wrapper script if your libraries are in such a place that curlew can't find them)

#!/bin/bash

export LD_LIBRARY_PATH=/usr/local/lib:$LD_LIBRARY_PATH
curlew
exit 0

To update the program: cd to the curlew folder and run sudo ./uninstall, then delete the folder, and then run the git clone command and install it again in the way shown above.

Screenshot of the program: it is easy to select the format you require, and bitrates and other settings can be specified by clicking the advanced tab.