Finding Codec in audio file using Apple APIs

1
votes

Is there a way to find the codec/container of an audio file using Apple APIs (AudioToolbox or Quicktime)?

1
codecquicktimeaudiotoolbox
I found that using "file" command gets me few data about codec. But, is there any other way to perform this action? And will "file" provide me the codec information all the time? – andrew

1 Answers

0
votes

You can practically read all possible information from a QuickTime movie using its internal movie atoms.

What you need is the "Sample Description Atom" of the sound track. You can find further information here : http://developer.apple.com/library/mac/#documentation/QuickTime/QTFF/QTFFChap3/qtff3.html#//apple_ref/doc/uid/TP40000939-CH205-75770

As can be seen, there are certain values defined for many kinds of different audio file formats. These QT Atoms are a bit tough to understand at first, but this is basically the way to go to retrieve all information necessary.

There is a tool by Apple called the "Atom Inspector" to give you an overview of all atoms a movie contains and their values.

Hope that helps!