iTunes and QuickTime AAC encoders

[aliumalik]

Hi,
A few questions. I encoded s file using QuickTime 6.5.1 and loaded it with iTunes (with th m4a extension) but it doesn't recognize that the file has been encoded with QuickTime. Am I doing something wrong?
Is there some significant difference between m4a and mp4? file headers etc
Is there anyway I can get itunes to recognize mp4 files just like m4a and display the tags etc?
Thanks

[tiki4]

What did you do exactly in Quicktime?

You have the possibility to encode e.g. a WAV file to the AAC format. MP4 and M4A extensions both refer to the MP4 container, where M4A means that it contains audio only. The encoders of Quicktime and iTunes are identical as iTunes installs Quicktime and its codecs.

Did you tag your M4A files outside iTunes? You can do this in a compliant way by using tgf.exe or foobar2000. Check your files for ID3 tags which could be problematic in iTunes and other applications.

By the way: You can also import WAV files into iTunes and encode and tag them there. As already mentioned iTunes also uses the Quicktime AAC codec.

Regards,

tiki4

P.S.: iTunes only recognizes the tags if the file extension is .m4a.

[bond]

Originally posted by aliumalik
but it doesn't recognize that the file has been encoded with QuickTime.what does this mean exactly? is itunes able to display the used encoder? does the file work correctly otherwise in itunes?

MP4 = M4A, there is no difference in any way. nothing can be done in one, which cant be done in the other. to sum it up: its 100% the same, simply the extension is different ;)

about non-itunes tagging aso.. it should never break a MP4 tool, as not known stuff in the udta atom should be simply ignored automatically