Hard going

Thu, 26 Jun 2008 23:17:02 +0100

I've spent about an hour this evening looking at the Apple developer documentation trying to figure out how to play music. By that I mean how to play musical notes through the (presumed) software synthesizer. I did this quite easily a few years ago with JavaSound but I'm not making much headway here. Even by Apple standards the documentation is terse and opaque.

Just to clarify that last statement I don't mean to suggest that Apple docs are especially bad but they're often little more than a thin wrapper around method and argument names, there is often little in the way of context or example usage. Unless you more or less know what you're doing it's often tough to figure it out from the Apple docs.

In this case I guess I want to use Core Midi with a software instrument. Maybe. Apparently I should have a (or maybe several) sound bank in /Library/Audio/Sounds/Banks/ but my cupboard is bare.

Nevertheless Apple supplies one example that appears to be headed in the right direction: PlaySoftMIDI. Bizarrely in these days of Cocoa marching foreward this is a C++ program and.. Carbon? I dunno. It's definitely not friendly Objective-C and Cocoa.

Also my heart did not sing as I read the opening comments:

// This is a simple test case of making an simple graph with a DLSSynth, Limiter and Ouput unit
// we're going to use a graph because its easier for it to just handle the setup and connections, etc...

You what now?

If anyone knows of any good Cocoa based examples of using CoreAudio or CoreMidi to generate music (i.e. playing notes, not playing MP3 files) I'd be very interested.

Curiouser and Curiouser! on core-audio

Hard going