AudioUnit basics
AudioUnit basics
- Subject: AudioUnit basics
- From: email@hidden
- Date: Sun, 16 Sep 2001 01:33:18 -0500 (CDT)
Hey,
So I'm planning out my next stage in my series of increasingly
complex-yet-amateurish CoreAudio apps and am contemplating using the
AudioUnit/AudioOutputUnit structures as mentioned in the CoreAudio docs.
The main problem - I don't have a clue how to go about doing it. The
CoreAudio docs aren't particularly helpful and AudioUnit.h file just
teaches me mainly that I don't know what things such as
typedef CALLBACK_API_C( ComponentResult , AudioUnitGetParameterProc )(void
*inComponentStorage, AudioUnitParameterID inID, AudioUnitScope inScope,
AudioUnitElement inElement, Float32 *outValue);
or
EXTERN_API( ComponentResult )
AudioUnitRemovePropertyListener(
AudioUnit ci,
AudioUnitPropertyID inID,
AudioUnitPropertyListenerProc inProc)
FIVEWORDINLINE(0x2F3C, 0x0008, 0x000B, 0x7000, 0xA82A);
mean as far as usage. It looks like there's no AudioUnit interface or
protocol, maybe EXTERN_API declares the methods an AudioUnit
should have available as public and CALLBACK_API_C...hmm, maybe they're
all supposed to be public. Anyway, I'd rather not guess so... any good
sample code of AudioUnits out there? I checked the archives and basically
all I see is someone else asking the same thing and no replies on the
list. Are AudioUnitPropertyID's and AudioUnitParameterID's
programmer-defined as opposed to Apple/API defined? What are their types
made of - are they ints, floats, 4 packed chars? Do I have any reason
to care about what's in AudioUnit.k.h? I have even less of a clue what
those EXTERN_API( ComponentResult
)ADD_AUDIOUNIT_BASENAME(MethodName?)(stuff....) declarations mean.
Last, it looks like AudioUnits require the use of C methods (as
opposed to allowing Obj-C methods) for everything specified - am I wrong?
*Sigh*
Thanks,
Ben D.