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<h4 align="left">Audio Queue Offline Render Test Sample</h4>

<p>Demonstrates the use of the AudioQueueOfflineRender API. All the relevant code is

in the file aqofflinerender.cpp. Touching the "Start" button simply calls

DoAQOfflineRender() producing LPCM output buffers from an ALAC encoded source file.

These buffers are then written to a .caf file which is played back after rendering using

AVAudioPlayer to confirm success.<p>

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<p>Audio Queue Services provides a straightforward, low overhead way to record

and play audio in iPhone OS and Mac OS X. It is the recommended technology

to use for adding basic recording or playback features to your iPhone OS or

Mac OS X application.</p>

<p>Offline rendering with an audio queue output allows applications to render

audio to a buffer instead of directly to an output device. This is

especially useful with the iPhone OS, since the Audio Converter and Extended

Audio File APIs do not currently (up to iPhone OS 2.2.x) support

decompressing AAC, ALAC or MP3 encoded audio to LPCM if further processing

is desired.</p>

<p>If you need to generate buffers of LPCM data from AAC, ALAC or MP3 encoded

audio, using audio queue offline rendering is the recommended approach.</p>

<p>Audio Queue Services lets you record and play audio in any of the following

formats:</p>

<ul>

<li> Linear PCM.</li>

<li> Any compressed format supported natively on the Apple platform you are

developing for.</li>

<li> Any other format for which a user has an installed codec.</li>

</ul>

<p>Audio Queue Services is high level. It lets your application use hardware

recording and playback devices (such as microphones and loudspeakers)

without knowledge of the hardware interface. It also lets you use

sophisticated codecs without knowledge of how the codecs work.

At the same time, Audio Queue Services supports some advanced features. It

provides fine-grained timing control to support scheduled playback and

synchronization, for example synchronizing playback of multiple audio

queues.</p>

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