Reproduce a part of a music clip (cocoa)

I'm newbie working with music clips and Cocoa.

I have a music clip long 10s and i want to reproduce only the first 4s. How can I do this thing ?

If i want to reproduce an interval between start and end for example between se开发者_如何转开发cond 4 and second 7. How can I do that ?

Thanks in advance.

You could do this with QTKit with a QTMovie object. QTMovie gives you all kinds of ways of editing, working with the audio tracks, selecting time ranges, etc. Spend some time looking over the linked doc and post specific questions if you get stuck.