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Introduction

This document has been replaced by Core Audio Overview and other audio documents in the ADC Reference Library. For iPhone OS development, refer to Getting Started with Audio & Video. For Mac OS X development, refer to Getting Started with Audio.

In this section:

About Core Audio
Additional Resources

About Core Audio

Core Audio presents a multitiered set of API services that developers can take advantage of in their applications. These range from low-level access to particular audio devices to sequencing and software-synthesis. The MIDI services present the capabilities of a MIDI device, which allow an application to interface to a device and manage and manipulate the MIDI data flow around the system.

These API services in Core Audio are presented in frameworks. A framework is a type of bundle that packages a dynamic shared library with the resources that the library requires, including header files. A framework bundle has an extension of .framework. Inside the bundle there can be multiple major versions of the framework.

The executable code in a framework is a dynamic shared library. Multiple, concurrently running programs can share the code in this library without requiring their own copy. As a packaging mechanism used by Mac OS X, frameworks present the runtime library that your application can run against, and the header files that you can use to link to.

Frameworks are implemented in C and C++ and present a C-based function API. There is also a Java API for these audio system services. The Java API primarily presents a corresponding C function or structure as a method on a Java class. There is as little overhead as possible in the interface of Java code to the underlying C implementation. Everything in the C interface you can accomplish using Java.

Because the Java API so closely follows the C API, if you are a Java developer, you need to understand the overall design of these frameworks in order to effectively use the provided services. The language choice is up to you, depending upon your development needs and requirements.

Additional Resources

Apple provides a number of resources available to assist developers. These include:

• The coreaudio-api mailing list: http://lists.apple.com/

• The developer website: http://developer.apple.com/audio

• Core Audio SDK: http://connect.apple.com

• Mac OS X development resources: http://developer.apple.com/macosx/

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