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<title>FAAC - ISO/MPEG 2/4 AAC Encoder Library</title>
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<h3>
<center>
FAAC - ISO/MPEG 2/4 AAC Encoder Library version 1.0<br>
(<a href="http://www.audiocoding.com/">www.audiocoding.com</a>)
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</h3>

<h4>
Contents
</h4>
<menu>
 <li><a href="#scope">Scope</a>
 <li><a href="#interface">Interface description</a>
 <li><a href="#usage">Usage</a>
 <menu>
  <li><a href="#callseq">Calling sequence</a>
 </menu>
 <li><a href="#funcref">Function reference</a>
 <menu>
  <li><a href="#init">Initialization / De-initialization</a>
  <menu>
   <li><a href="#encopen">faacEncOpen()</a>
   <li><a href="#encclose">faacEncClose()</a>
  </menu>
  <li><a href="#encconf">Encoder configuration</a>
  <menu>
   <li><a href="#getconf">faacEncGetCurrentConfiguration()</a>
   <li><a href="#setconfig">faacEncSetConfiguration()</a>
  </menu>
  <li><a href="#encfunc">Encoding functions</a>
  <menu>
   <li><a href="#encenc">faacEncEncode()</a>
  </menu>
 </menu>
  <li><a href="#datastruct">Data structures reference</a>
  <menu>
  <li><a href="#encconfig">faacEncConfiguration</a>
  </menu>
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<a name="scope">
<h4>Scope</h4>
This document describes the interface and usage of the
FAAC - ISO/MPEG 2/4 AAC Encoder Library
Developed for the Freeware Advanced Audio Coding project.

<a name="interface">
<h4>Interface description</h4>
The ISO/MPEG 2/4 AAC Encoder Library provides a high-level
interface for encoding MPEG2 and MPEG4 ISO AAC files. The
following header file is provided for usage in C/C++ programs:<br><br>

<b>faac.h</b>: function prototypes<br><br>

The encoder core resides in a statically linkable library called

libfaac.lib <i>(Microsoft Window</i>s) or libfaac.a <i>(UNI</i>X). There
are various example programs that show how to use the library.

<a name="usage">
<h4>Usage</h4>

<a name="callseq">
<h4>Calling sequence</h4>

For encoding AAC bitstreams the following calling sequence is
mandatory:<br>

<menu>
<li>Call <i>faacEncOpen()</i>
 for every encoder instance you need.
<li>To set encoder options, call <i>faacEncGetCurrentConfiguration()</i>,
 change the parameters in the structure accessible by the returned pointer
 and then call <i>faacEncSetConfiguration()</i>.
<li>As long as there are still samples left to encode, call
 <i>faacEncEncode()</i>
 to encode the data.
 The encoder returns
 the bitstream data in a client-supplied buffer.
<li>
 Once you call
 <i>faacEncEncode()</i>
 with zero samples of input
 the flushing process is initiated; afterwards you may call
 <i>faacEncEncode()</i>
 with zero samples input only.<br>
 <i>faacEncEncode()</i> will continue to write out data until all audio
 samples have been encoded.
<li>
 Once 
 <i>faacEncEncode()</i>
	has returned with zero bytes written,
	call <i>faacEncClose()</i>
	to destroy this encoder instance.
</menu>

<a name="funcref">
<h4>Function reference</h4>

<a name="init">
<h4>Initialization / De-initialization</h4>

<a name="encopen">
<h5><i>faacEncOpen()</i></h5>

<pre>
<b>Prototype</b>
faacEncHandle FAACAPI faacEncOpen
(
unsigned long sampleRate,
unsigned int numChannels,
unsigned long *inputSamples,
unsigned long *maxOutputBytes
);
<b>Description</b>
Open and initialize one instance of the encoder.
<b>Parameters</b>
<li><i>sampleRate</i>
	The samplerate of the encoder input data.
<li><i>numChannels</i>
	The number of channels of the encoder input data.
<li><i>inputSamples</i>
	Receives the total number of samples that should be fed to
	faacEncEncode() in each call.
<li><i>maxOutputBytes</i>
	Receives the maximum number of bytes that can be in the
	output buffer after a call to faacEncEncode().
<b>Return value</b>
An initialized encoder handle. If anything goes wrong NULL is returned.
</pre>

<a name="encclose">
<h5><i>faacEncClose()</i></h5>
<pre>
<b>Prototype</b>
void FAACAPI faacEncClose
(
faacEncHandle hEncoder
);
<b>Description</b>
Closes an encoder instance.
<b>Parameters</b>
<li>hEncoder
	An encoder handle returned by faacEncOpen().
</pre>

<a name="encconf">
<h4>Encoder configuration</h4>

<a name="getconf">
<h5><i>faacEncGetCurrentConfiguration()</i></h5>

<pre>
<b>Prototype</b>
faacEncConfigurationPtr FAACAPI
faacEncGetCurrentConfiguration
(
faacEncHandle hEncoder
);
<b>Description</b>
Get a pointer to a structure describing the current encoder
configuration. You may change this structure and feed it into
<i>faacEncSetConfiguration()</i>.
</pre>

<a name="setconf">
<h5><i>faacEncSetConfiguration()</i></h4>

<pre>
<b>Prototype</b>
int FAACAPI faacEncSetConfiguration
(
faacDecHandle hDecoder,
faacEncConfigurationPtr config
);
<b>Description</b>
Set a new encoder configuration. See
faacEncGetCurrentConfiguration().
</pre>


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Copyright &copy; 2001,2003 <a href="http://www.audiocoding.com/">AudioCoding.com</a>. All rights reserved.
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