Re: digital audio tutorial
Re: digital audio tutorial
- Subject: Re: digital audio tutorial
- From: Jeff Moore <email@hidden>
- Date: Tue, 08 Jan 2002 10:52:15 -0800
on 1/7/02 10:00 PM, Eddie Liu <email@hidden> wrote:
>
I'm a computer audio newbie. I've been able to use the sample code
>
to have core audio record a bit of audio from the microphone and play
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it back, but I still don't really understand what I'm doing. For
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example, how do I get the sample size and rate from a particular
>
device, in this case the built-in mic?
You want to use the property mechanisms in the HAL to find out information
about the device you are using.
Better still, for most purposes you should use the Output AudioUnit to do
your IO rather than the HAL API directly. The Output AudioUnits shield you
from a lot of the complexities of dealing with the HAL.
>
I found the core audio tutorial which has helped some, but can
>
anybody point me towards a more general beginner tutorial about
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digital audio?
One of my favorite introductory books is "The Programmer's Guide to Sound"
by Tim Kientzle (ISBN: 0-201-41972-6). It has good sections that introduce a
lot of the concepts used in digital audio (like sampling theory and what
not), but doesn't go too deeply into them which is just right for an
introductory book.
This book was written well before Mac OS X and CoreAudio came around so the
code examples focus on Windows Sound and the Sound Manager, but there is
enough general info there that you should get yourself grounded pretty
quickly. The Sound Manager code should even still compile and run on X for
the most part although I haven't checked.
--
Jeff Moore
Core Audio
Apple