A document based Cocoa application for playing audio. It should include a waveform display with a playhead for scrubbing, and the ability to speed up and slow down playback (using Apple's AUTimePitch audio unit).
## Deliverables
I have an idea for an audio application, but it's been a long time since I've done any Cocoa or Core Audio programming, so I'd like to have someone more experienced write the basic foundations.
When you open a file it should show a nice preview of the waveform. You should
be able to zoom in horizontally on the waveform, and scroll around. It should
have buttons for your standard controls - play pause, stop, go back to the
beginning. There should be a playhead which moves as the file plays, and the
waveform should scroll with the playhead. You should also be able to drag the
playhead to move around within the file.
I would also like a slider to control playback speed (using the AUTimePitch
audio unit). The playhead should stay in sync with the modified playback speed.