Re: AU in XCode - beginner problems
Re: AU in XCode - beginner problems
- Subject: Re: AU in XCode - beginner problems
- From: William Stewart <email@hidden>
- Date: Sat, 8 May 2004 13:46:05 -0700
I would start with the SampleEffect component in the CoreAudio SDK
(Developer/Examples/CoreAudio/AudioUnits/SampleAUs)
On 08/05/2004, at 5:14 AM, Toine Heuvelmans wrote:
>
Hi,
>
I have to find out how to create an AudioUnit (using XCode) for school
>
(I'm an AudioDesign student at the HKU, specialisation Software
>
Development), but for the last two months I've got nothing but errors.
>
There's some progress, but I still don't even have a simple GainAU.
>
I know some of the basics, because I had some help from Andrew Ostler
>
(expertsleepers) and from Cees Taal, who directed me to
>
http://lists.apple.com/archives/coreaudio-api/2004/Jan/11/
>
documenation.001.txt
>
and the CoreAudio Swiki (which is momentarily offline or something)
>
but a lot of questions remain, and I have to document everything I do
>
(for school) so I need to know what I'm doing.
>
>
First of all some things that should be easy to answer:
>
1. Which methods do I need to implement to build the most basic (let's
>
say Effect)AudioUnit? (to just get a successful build)
The Sample AU does a simple pass through, but its pretty self
explanatory - you should be able to copy the sample aus directory over
to your dev directory, and the paths will be fine, and it should just
build...
We fixed problems with this - so if you download the latest SDK from
http://developer.apple.com/audio you should be able to do this (if not
let us know) - We'll check this ourselves on monday and post any
problems (and their solutions) to the list.
(The SDK installs files into both Developer/Examples/CoreAudio and
Developer/Documentation/CoreAudio)
>
>
2. What exactly is a component?
a component is a dynamically loaded piece of code. components are found
through 3 discriminating fields:
type
sub type
manufacturer.
For an individual component, each of these must add up to a unique ID.
For an AU Effect the type is 'aufx' - that is required to identify an
effect AU
A subtype is free to use by you
manufacturer is a code that you can register to ensure that you have a
unique name space (your own manuID)
>
3. There are various returntypes, like ComponentResult and OSStatus.
>
What does it return?
ComponentResults are result codes that are defined by the
ComponentManager - thus calls for an AU that return this are called by
the component selectors (this is the API - so when you implement an AU,
you implement a set of APIs and this is called on your instance)
There's some basic docs on this and how it interacts with your AU in
the Developer/Documentation/CoreAudio section
>
4. Today I started all over again (for the Xst time, I've lost count)
>
from scratch, imported SDK files, frameworks, adjusted the target
>
(carbon bundle>>component) and created the .exp and resources files,
>
but nothing in my plugin file. I had only 1 error in my resources file
>
(the best result in 2 months) but I could not recover what's wrong:
>
"SysError 0 during open of "ConditionalMacros.r". Fatal Error, can't
>
recover."
>
So what am I doing wrong?
>
>
5. One time I succeeded in just outputting a totally empty component.
>
But this was a dirictory with "contents" and in that the Info.plist and
>
Resources. Is this right, would this (if containing all stuff for an
>
AU) be recognised as a component, because all the AU's I've downloaded
>
can't be opened as a normal directory...
>
>
6. Any nice links, hints, advices?
>
>
Thank you if you can answer one or more of these questions!
>
>
Toine Heuvelmans [Netherlands]
>
Student Audio Design (second year)
>
email@hidden
>
http://www.hku.nl
>
_______________________________________________
>
coreaudio-api mailing list | email@hidden
>
Help/Unsubscribe/Archives:
>
http://www.lists.apple.com/mailman/listinfo/coreaudio-api
>
Do not post admin requests to the list. They will be ignored.
>
>
--
mailto:email@hidden
tel: +1 408 974 4056
________________________________________________________________________
__
Culture Ship Names:
Ravished By The Sheer Implausibility Of That Last Statement
I said, I've Got A Big Stick [OU]
Inappropiate Response [OU]
Far Over The Borders Of Insanity And Still Accelerating [Eccentric]
________________________________________________________________________
__
_______________________________________________
coreaudio-api mailing list | email@hidden
Help/Unsubscribe/Archives:
http://www.lists.apple.com/mailman/listinfo/coreaudio-api
Do not post admin requests to the list. They will be ignored.