How to encode QuickTime audio & video
To encode QuickTime audio & video, use... QuickTime.
Well, not exactly : use QuickTime "Pro".
When downloading QuickTime on the Apple website, one always downlaod the
"free" version, which cannot encode anything.
But this free version can be turned to a "Pro" ( complete ) version just by entering a serial number, which you can either buy or find somewhere on the web - and it is rather easy to find, very easy if you run the Windows version.
The "Pro" version is very practical : whereas QuickTime audio codecs are not this good, the video codecs are really worth it. And you can use QuickTime Pro to encode MP3 audio as well.
Also, QuickTime Pro possesses two interesting features : some basic audio / video editing tools, and the very nice ability to decode MP3 files into standard .wav or .aiff files.
To download QuickTime's free version, go there.