shithub: aacenc

ref: 459dbbc305d6cf91a97203fff54c93e3d6e25487
dir: /docs/faac.html/

View raw version
<html>

<head>
<title>
FAAC - Freeware Advanced Audio Coder
</title>
</head>

</body>

<h3>
<center>
FAAC 1.18 beta (<a href="http://www.audiocoding.com/">www.audiocoding.com</a>)
</center>
</h3>
<br>

<a name="toc">
<h3>
Contents
</h3>
<menu>
<li><a href="#usage">Usage</a>
<menu>
<li><a href="#opts">options</a>
<li><a href="#notes">notes</a>
</menu>
<li><a href="#copyrights">Copyrights</a>
<li><a href="#patents">Patents</a>
<li><a href="#people">People</a>
</menu>

<br><br>
<a name="usage">
<h3>
Usage
</h3>
(More up to date info can be found at
<a href="http://www.audiocoding.com/wiki/index.php?page=FAAC">
FAAC wiki page</a> by Hans-J&uuml;rgen Bardenhagen)<br><br>
<kbd>faac [options] &lt;infile&gt; &lt;outfile&gt;</kbd>
<br><br>

<a name="opts">
<b>Options:</b><br>
<menu>
<li>
<kbd>-a X</kbd>
	Set average bitrate to approximately X kbps per channel
	(i.e. using -a 64 averages at 128 kbps/stereo).
<li>
<kbd>-c &lt;bandwidth&gt;</kbd>
	Set the bandwidth in Hz (default value depends on sample rate)
<li>
<kbd>-q &lt;quality&gt;</kbd>
	Set quantizer quality (default: 100, averages at approx. 128 kbps VBR for
	a normal stereo input file at 16 bit and 44.1 kHz sample rate).
<li>
<kbd>--tns</kbd>
	Enable TNS coding.
<li>
<kbd>--notns</kbd>
	Disable TNS coding.
<li>
<kbd>-n</kbd>
	Disable mid/side coding.
<li>
<kbd>-m X</kbd>
	AAC MPEG version, X can be 2 or 4 (default: MPEG-2, so for
	the sake of interoperability with non-standard compliant players
	like QuickTime 6 you should set it to "4").
<li>
<kbd>-o X</kbd>
	AAC object type, X can be LC, MAIN or LTP (default: LC, for the
	same reason as with the MPEG version don't use Main or LTP).
<li>
<kbd>-r</kbd>
	RAW AAC output file (i.e. without ADTS headers).
<li>
<kbd>-P</kbd>
	Raw PCM input mode.
<li>
<kbd>-R</kbd>
	Raw PCM input sample rate in Hz (default: 44100 Hz).
<li>
<kbd>-B</kbd>
	Raw PCM input bit depth (default: 16 bits, also possible 8 bits).
<li>
<kbd>-C</kbd>
	Raw PCM input channels (default: 2).
</menu>

<kbd>- &lt;stdin&gt;</kbd>
  If you simply use a hyphen/minus sign instead of an input
  file name, FAAC can encode directly from stdin, thus enabling piping
  within other applications like foobar2000 or mp4live.
<br><br>

<a name="notes">
<strong>Note:</strong> VBR output bitrate depends on -q
<em><strong>AND</strong></em> -c, so you should only vary the default
setting -q 100 -c 16000 if you know what you're doing and/or want to
experiment with other cutoff frequencies at a given quality setting.
<br><br>
The ABR setting with -a is an approximate average bitrate that does not use 
a bit reservoir, i.e -a 64 and -q 100 at 44.1 kHz will result in exactly 
the same output file.<br>
<br>
The following list should give some orientation for useful -q and -c settings,
based on FAAC v1.17. The resulting VBR bitrates are referring to an average
sounding stereo file with 16bit, 44.1 kHz, i.e. 
ct_reference.wav in this case. Multiplexing these AAC files to MP4 with e.g. mp4creator will result in a ~3 kbps lower bitrate because of the stripped ADTS headers:<br>
<br>
-q 130 -c 22000 -m 4 (~218 kbps)<br>
-q 120 -c 20000 -m 4 (~194 kbps)<br>
-q 110 -c 18000 -m 4 (~158 kbps)<br>
-q 100 -c 16000 -m 4 (~129 kbps)<br>
-q 90 -c 14000 -m 4 (~103 kbps)<br>
-q 80 -c 12000 -m 4 (~79 kbps)<br>
-q 70 -c 10000 -m 4 (~62 kbps)<br>
<br>
The added -m 4 switch does not change the bitrate or sound of course,
but is recommended for most AAC/MP4 players that use an updated FAAD2-based
plugin from this year (Winamp 2.x, foobar2000 etc.) or can't decode
MPEG-2 AAC LC files like QuickTime 6. Philips Expanium users should not use
this switch, because their CD portable does not know MPEG-4 AAC files.
<br>


<br><br><br>
<a name="copyrights">
<h3>
Copyrights
</h3>
FAAC - Freeware Advanced Audio Coder
(<a href="http://www.audiocoding.com/">www.audiocoding.com</a>)
<pre>
	Portions Copyright &copy; 1999,2000,2001 Menno Bakker
	Portions Copyright &copy; 2002,2003 Krzysztof Nikiel
</pre>
FAAC is based on the ISO MPEG-4 reference code. For this base code the
following license applies:
<br>
<pre>
This software module was originally developed by

FirstName LastName (CompanyName)

and edited by

FirstName LastName (CompanyName)
FirstName LastName (CompanyName)

in the course of development of the MPEG-2 NBC/MPEG-4 Audio standard
ISO/IEC 13818-7, 14496-1,2 and 3. This software module is an
implementation of a part of one or more MPEG-2 NBC/MPEG-4 Audio tools
as specified by the MPEG-2 NBC/MPEG-4 Audio standard. ISO/IEC gives
users of the MPEG-2 NBC/MPEG-4 Audio standards free license to this
software module or modifications thereof for use in hardware or
software products claiming conformance to the MPEG-2 NBC/ MPEG-4 Audio
standards. Those intending to use this software module in hardware or
software products are advised that this use may infringe existing
patents. The original developer of this software module and his/her
company, the subsequent editors and their companies, and ISO/IEC have
no liability for use of this software module or modifications thereof
in an implementation. Copyright is not released for non MPEG-2
NBC/MPEG-4 Audio conforming products. The original developer retains
full right to use the code for his/her own purpose, assign or donate
the code to a third party and to inhibit third party from using the
code for non MPEG-2 NBC/MPEG-4 Audio conforming products. This
copyright notice must be included in all copies or derivative works.

Copyright &copy; 1997.
</pre>

<br>
For the changes made for the FAAC project the GNU Library General
Public License (LGPL), version 2 1991 applies. For the changes the
following statement applies:
<br>

<pre>
FAAC - Freeware Advanced Audio Coder
Copyright &copy; 1999,2000,2001,2002,2003 <a href="#people">FAAC developers</a>

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
</pre>

<br>
<a name="patents">
<h3>
Patents
</h3>
Please note that the use of this software may require the payment of
patent royalties. You need to consider this issue before you start
building derivative works. We are not warranting or indemnifying you in
any way for patent royalities! YOU ARE SOLELY RESPONSIBLE FOR YOUR OWN
ACTIONS!
<br>


<br><br><br>
<a name="people">
<h3>
People
</h3>

<i>Currently maintained by</i> M. Bakker (menno)</a><br><br>

<i>Other contributors:</i><br>
Tony Lenox<br>
RageOMatic<br>
thebard<br>
Ivan Dimkovic<br>
Krzysztof Nikiel (knik)<br>
Janne Hyv�rinen (ca5e)<br>
Stuart Espey (stux)<br>
Andrew Voznytsa<br>
M�ns Rullg�rd<br>
Bill May<br>

<br><br>

<h6>
<center><i>
Copyright &copy; 2003 <a href="http://www.audiocoding.com/">AudioCoding.com</a>
<br></i></center>
</h6>

</body>
</html>