I do not have a very big mp3 music files collection, just 2 to 3 gigs of them, but I have made it over the years, and some of the original CDs are missed, so I can not import them again.

I am using an iPod Touch and iTunes to hear my collection, and all the music I have bought from itunes is nicely classified, and I have the Album picture also available, but with my old imported music I do not have it, because the tags are not properly set.

I have stumbled into this great application, which is written in phyton, and therefore is available for Linux, I am actually using Arch Linux and for this distro it is available through community.

So just enter:

yaourt picard

And you will get this:

1 community/picard 0.12.1-1
     Next generation MusicBrainz tagging application (QT4 interface)
2 aur/picard-bzr 978-2 (12)
    Next generation MusicBrainz tagging application (bzr version)
3 aur/picard-plugins 0.12-3 (50)
    Plugins for MusicBrainz Picard
4 aur/picard-plugins-lastfmplus 0.12-2 (3)
    LastFMPlus Plugin for MusicBrainz Picard
5 aur/picard-plugins-search 0.12-1 (23)
    search plugins for MusicBrainz Picard
6 aur/picard-qt 0.9.0beta1-2 (Out of Date) (40)
    Next generation MusicBrainz tagging application (QT4 interface)
==>  Enter n° (separated by blanks, or a range) of packages to be installed
==>   ----------------------------------------------

Select number 1 and install the community version, if you do not have yaourt installed you can use pacman instead.

Once installed just run it, from the menu, or from a console

picard &

You will see a screen like this:

picard tagger screenshot</img>

From the menu Options -> Options select Moving files, you will get a screen like the one below.

picard tagger screenshot</img>

Enter the folder where you want to be copied your new tagged files, I usally use /tmp/ as from there I then import them to iTunes (I use windows in a Virtual Box for iTunes)

Now just add files or folders you may want to analyze and click on scan, you will have their tags updated, after it finished, if you are satisfied with the results, click on save to have a copy of your mp3, with the right tags in your /tmp/ folder.

You can now import it to iTunes and use it on your iPod or iPhone, or use it as you wish.

For more info about picard, go to Musicbrainz