MPEG-4 files with audio streams encrypted by FairPlay Digital Rights Management as were sold through the iTunes Store use the .m4p extension. iTunes Plus tracks, that the iTunes Store currently sells, are unencrypted and use .m4a accordingly.
That being said, the m4p music can only be used or played back within Apple environment, including iTunes, iPad, iPod, iPhone, iMovie, iDVD, etc. If, for instance, you want to play m4p songs on a non-Apple media device, you need to convert m4p to mp3 first. Most audio conversion tools cannot convert m4p files due to the DRM. However, you can still free your iTunes music library and convert iTunes m4p music to mp3 on Mac without paying for any music DRM removal software using either of the methods below:
1. Convert m4p to mp3 on Mac by burning a CD disc and ripping it back
a. Insert a CD-R or CD-RW disc into your CD-ROM drive
b. Run iTunes, create a new playlist and burn it to make an “Audio CD”
c. After the Audio CD is successfully burned, insert the disc into your CD-ROM drive again. Then you can use iTunes to import the music tracks on the burned disc as whatever format (MP3, AAC, etc) you selected in iTunes preferences for importing.
2. Convert m4p to mp3 on Mac using iMovie
Run iMovie and create a New Project.
In the iMovie window, select the ‘Music’ tab. You will notice that the top right portion of the interface now offers a media browser. Locate the playlist which contains purchased music, or search by artist/title.
Select the DRM-laden song and drag the file from the media browser into the iMovie timeline.
In order to export the song, iMovie requires that a visual image be associated with the audio track – iMovie thinks that it is going to be exporting a movie. Simply drag a blank image (or any other image) to the track above the previously imported audio file. Once iMovie has processed the image, select the ‘Export using QuickTime…’ sub menu item from found inside ‘Share’ in iMovie’s menu bar.
In the Save as… dialogue, select “Sound to AIFF” in the Export drop-down menu, Choose an appropriate directory for iMovie to export to, title the file, and select ‘Save’.
Locate the exported AIFF audio file and drag to your iTunes Library. Right-click on the file and select “Create MP3 Version”. Once completed, ‘Get Info’ on the new file, edit meta data, add album art, and trash the originally purchased and AIFF audio files from your iTunes library.
You may have noticed that it is a time-consuming process to convert m4p to mp3 on Mac OS X with either of the above methods if you have hundreds of music files ready to be converted. TuneClone is a pretty good alternative. TuneClone is built in a virtual CD burner to convert iTunes music to mp3 with ease and speed. All you need to do is burn your iTunes playlist to TuneClone virtual CD instead of real CD discs. TuneClone will convert m4p music in the playlist to MP3 files with CD quality at high speed remaining all the original music meta information.