these tools are great too:1- Curlew Multi Converter:
Curlew is multi-converter tool, it is based on ffmpeg. Curlew is easy to use, free and open-source multimedia converter for Linux. Curlew converter can convert to over 117 different formats. Curlew written in python and GTK3 and it depends on (ffmpeg/avconv, mencoder).
to install follow this http://www.noobslab.com/2014/01/curlew-multi-converter-updated-to.html2- Format Junkie media converter
It converts a variety of audio and video formats, and even can convert ISOs to other disc images (in this case the CSO disc image). In addition to audio, video, and disc image files, this converter even converts images and converts all the popular formats!
A Graphical User Interface user-friendly application with lots of options, which can convert your media files to all the popular formats! Unity integration has been bear in mind.
To install follow this http://www.noobslab.com/2014/01/format-junkie-converter-for-ubuntu.html3- soundconverter:
Soundconverter is a simple sound converter application for the gnome environment. it reads sound files in any format supported by gstreamer and outputs them in ogg vorbis, flac, or wav format, or mp3 format if you have the gstreamer lame plugin.
to install follow this http://community.linuxmint.com/software/view/soundconverter4- HandBrake:
HandBrake is a tool for converting video from nearly any format to a selection of modern, widely supported codecs. HandBrake is an open-source, GPL-licensed, multiplatform, multithreaded video transcoder, available for MacOS X, Linux and Windows.
to install follow thishttp://www.noobslab.com/2013/12/handbrake-video-converter-for.html5- winff:
Winff is a graphical user interface for ffmpeg or avconv. it will convert almost any video file that ffmpeg or avconv will convert. winff does multiple files in multiple formats at one time. you can, for example, convert mpeg's, flv's, and mov's into avi's (or dvd/vcd format or mpeg or 3gp etc.) all at once.
this package provides a variety of preset conversion settings for common formats and devices. these presets are intended to hit the "sweet spot" for each individual codec. they have been written with a tip of the balance to quality.
for most presets to work, it is necessary to have the unstripped version of the libavcodec package, which can be obtained by installing libavcodec-extra-## as suggested by this package. it might be necessary to enable additional repositories to find that package.
to install followhttp://community.linuxmint.com/software/view/winff
More converters include gnormalize, OggConvert, soundKonverter, DeVeDe....
full tutorial here http://community.linuxmint.com/tutorial/view/1238