FAAC (Freeware Advanced Audio Coder) is a software project which includes the

AAC AAC may refer to: Aviation * Advanced Aircraft, a company from Carlsbad, California * Airborne aircraft carrier, a type of aircraft * Alaskan Air Command, a radar network * American Aeronautical Corporation, a company from Port Washington, New ...

encoder FAAC and

decoder Decoder may refer to: Technology * Audio decoder converts digital audio to analog form * Binary decoder, digital circuits such as 1-of-N and seven-segment decoders * Decompress (compression decoder), converts compressed data (e.g., audio/video/i ...

FAAD2. It supports

MPEG-2 MPEG-2 (a.k.a. H.222/H.262 as was defined by the ITU) is a standard for "the generic coding of moving pictures and associated audio information". It describes a combination of lossy video compression and lossy audio data compression methods ...

AAC as well as

MPEG-4 MPEG-4 is a group of international standards for the compression of digital audio and visual data, multimedia systems, and file storage formats. It was originally introduced in late 1998 as a group of audio and video coding formats and related ...

AAC. It supports several

MPEG-4 Audio MPEG-4 Part 3 or MPEG-4 Audio (formally ISO/ IEC 14496-3) is the third part of the ISO/ IEC MPEG-4 international standard developed by Moving Picture Experts Group. It specifies audio coding methods. The first version of ISO/IEC 14496-3 was publis ...

object types (LC, Main, LTP for encoding and SBR, PS, ER, LD for decoding), file formats (ADTS AAC, raw AAC, MP4), multichannel and gapless encoding/decoding and MP4 metadata tags. The encoder and decoder is compatible with standard-compliant audio applications using one or more of these object types and facilities. It also supports

Digital Radio Mondiale Digital Radio Mondiale (DRM; ''mondiale'' being Italian and French for "worldwide") is a set of digital audio broadcasting technologies designed to work over the bands currently used for analogue radio broadcasting including AM broadcasting—p ...

. FAAC and FAAD2, being distributed in C

source code In computing, source code, or simply code or source, is a plain text computer program written in a programming language. A programmer writes the human readable source code to control the behavior of a computer. Since a computer, at base, only ...

form, can be

compiled In computing, a compiler is a computer program that translates computer code written in one programming language (the ''source'' language) into another language (the ''target'' language). The name "compiler" is primarily used for programs that ...

on various platforms and are distributed free of charge. FAAD2 is

free software Free software, libre software, libreware sometimes known as freedom-respecting software is computer software distributed open-source license, under terms that allow users to run the software for any purpose as well as to study, change, distribut ...

. FAAC contains some code which is published as Free Software, but as a whole it is only distributed under a proprietary license. FAAC was originally written by Menno Bakker.

FAAC encoder

FAAC stands for Freeware Advanced Audio Coder. The FAAC encoder is an audio compression computer program that creates AAC (MPEG-2 AAC/MPEG-4 AAC) sound files from other formats (usually,

CD-DA Compact Disc Digital Audio (CDDA or CD-DA), also known as Digital Audio Compact Disc or simply as Audio CD, is the standardization, standard format for audio compact discs. The standard is defined in the ''Rainbow Books, Red Book'' technical s ...

audio files). It contains a library (libfaac) that can be used by other programs. AAC files are commonly used in computer programs and portable music players, being

Apple Inc. Apple Inc. is an American multinational corporation and technology company headquartered in Cupertino, California, in Silicon Valley. It is best known for its consumer electronics, software, and services. Founded in 1976 as Apple Comput ...

's recommended format for the company's

iPod The iPod is a series of portable media players and multi-purpose mobile devices that were designed and marketed by Apple Inc. from 2001 to 2022. The iPod Classic#1st generation, first version was released on November 10, 2001, about mon ...

music player. Some of the features that FAAC has are: cross-platform support, "reasonably" fast encoding, support for more than one "object type" of the AAC format, multi-channel encoding, and support for

streams. It also supports multi-channel streams, like 5.1. The MPEG-4 object types of the AAC format supported by FAAC are the "Low Complexity" (LC), "Main", and "Long Term Prediction" (LTP). The MPEG-2 AAC profiles supported by FAAC are LC and Main. The SBR and PS object types are not supported, so the

HE-AAC High-Efficiency Advanced Audio Coding (HE-AAC) is an audio coding format for lossy data compression of digital audio as part of the MPEG-4 standards. It is an extension of Low Complexity AAC (AAC-LC) optimized for low- bitrate applicati ...

and HE-AACv2 profiles are also not supported. The object type "Low Complexity" is the default and also happens to be used in videos meant to be playable for portable players (like Apple's iPod) and used by video-hosting sites (like

YouTube YouTube is an American social media and online video sharing platform owned by Google. YouTube was founded on February 14, 2005, by Steve Chen, Chad Hurley, and Jawed Karim who were three former employees of PayPal. Headquartered in ...

). FAAC has been evaluated as a somewhat "lower quality" option than other aac encoders.

Alternatives for AAC encoding in Unix-like operating systems

FAAC is one of six alternatives that

Linux Linux ( ) is a family of open source Unix-like operating systems based on the Linux kernel, an kernel (operating system), operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically package manager, pac ...

Unix Unix (, ; trademarked as UNIX) is a family of multitasking, multi-user computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, a ...

users have for creating AAC files. The others are: * The Fraunhofer-developed " FDK AAC" encoder library included as part of Android. The FDK AAC source code is licensed under a custom-copyleft license, and has been ported to other platforms as libfdk-aac. The library is built around fixed-point math and supports only 16-bit PCM input. * The

Nero AG Nero AG (known as Ahead Software AG until 2005) is a German computer software company that is especially well known for its CD/ DVD/ BD burning suite, ''Nero Burning ROM''. The company's main product is Nero 2019, a piece of software that co ...

-developed "

Nero AAC Codec __NOTOC__ Nero AAC Codec is a set of software tools for encoding and decoding Advanced Audio Coding (AAC) format audio, and editing MPEG-4 metadata. It was developed and distributed by Nero AG, and is available at no cost for Windows and Linux ...

", which has a proprietary license, and is not available for the entire range of hardware architectures that these operating systems are able to run. Nero no longer develops this encoder, but the package is still available, and it remains a high-quality option for AAC encoding. * The

libavcodec libavcodec is a free and open-source library of codecs for encoding and decoding video and audio data. libavcodec is an integral part of many open-source multimedia applications and frameworks. The popular MPV, xine and VLC media players use ...

native AAC encoder (separate versions maintained by

FFmpeg FFmpeg is a free and open-source software project consisting of a suite of libraries and programs for handling video, audio, and other multimedia files and streams. At its core is the command-line ffmpeg tool itself, designed for processing vide ...

and

Libav FFmpeg is a free and open-source software project consisting of a suite of libraries and programs for handling video, audio, and other multimedia files and streams. At its core is the command-line ffmpeg tool itself, designed for processing video ...

) was experimental but considered "better than vo-aacenc" in at least some tests. It was written by Konstantin Shishkov, and released under version 2.1 of the

LGPL The GNU Lesser General Public License (LGPL) is a free-software license published by the Free Software Foundation (FSF). The license allows developers and companies to use and integrate a software component released under the LGPL into their own ...

. The AAC encoder used in FFmpeg's version of libavcodec was significantly improved for version 3.0 of FFmpeg and is no longer considered experimental. Libav has not merged this work. * libvo_aacenc, the Android VisualOn AAC encoder. This encoder was replaced in Android by the FDK AAC encoder mentioned above, and is considered a poor-quality option. * The (nonfree) libaacplus which implements the

High-Efficiency Advanced Audio Coding High-Efficiency Advanced Audio Coding (HE-AAC) is an audio coding format for lossy data compression of digital audio as part of the MPEG-4 standards. It is an extension of Low Complexity AAC (AAC-LC) optimized for low- bitrate application ...

. *

Mac OS X macOS, previously OS X and originally Mac OS X, is a Unix, Unix-based operating system developed and marketed by Apple Inc., Apple since 2001. It is the current operating system for Apple's Mac (computer), Mac computers. With ...

users can utilize Apple's AAC encoder with the command-line afconvert tool.

FAAD2 decoder

FAAD2 is Freeware Advanced Audio (AAC) Decoder including SBR decoding. It is MPEG-2 and MPEG-4 AAC decoder and supports MPEG-4 audio object types LC, Main, LTP, LD, ER, SBR and PS, which can be combined also to HE-AAC and HE-AACv2 Profile (AAC LC+SBR+PS). It contains a library (libfaad) that can be used by other programs. FAAD and FAAD2 were originally written by Menno Bakker from

. FAAD2 is the successor to FAAD1, which was deprecated. FAAD is Freeware Advanced Audio Decoder. It was first released in 2000 and it did not support SBR and PS audio object types. The last version of FAAD1 was ''2002-01-04''. All development later focused in FAAD2. The SBR decoding support (HE-AAC) was added in the version release on 25 July 2003. FAAD2 version 2.0 was released on 6 February 2004.

Licensing

FAAC contains code based on the

ISO The International Organization for Standardization (ISO ; ; ) is an independent, non-governmental, international standard development organization composed of representatives from the national standards organizations of member countries. Me ...

MPEG-4 reference code, whose license is not

compatible Compatibility may refer to: Computing * Backward compatibility, in which newer systems can understand data generated by older ones * Compatibility card, an expansion card for hardware emulation of another device * Compatibility layer, component ...

with the

license. Only the FAAC changes to this ISO MPEG-4 reference code are licensed under the LGPL license. The ISO MPEG-4 reference software was published as ISO/IEC 14496-5 (MPEG-4 Part 5: Reference software) and it is freely available for download from ISO website. 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. FAAD2 is licensed under the

GPL The GNU General Public Licenses (GNU GPL or simply GPL) are a series of widely used free software licenses, or ''copyleft'' licenses, that guarantee end users the freedom to run, study, share, or modify the software. The GPL was the first c ...

v2 (and later GPL versions). Code from FAAD2 is

copyright A copyright is a type of intellectual property that gives its owner the exclusive legal right to copy, distribute, adapt, display, and perform a creative work, usually for a limited time. The creative work may be in a literary, artistic, ...

of Nero AG (the "appropriate copyright message" mentioned in section 2c of the GPLv2). The source code contains a note that the use of this software may require the payment of

patent A patent is a type of intellectual property that gives its owner the legal right to exclude others from making, using, or selling an invention for a limited period of time in exchange for publishing an sufficiency of disclosure, enabling discl ...

royalties. Commercial non-GPL licensing of this software is also possible. FAAD (FAAD1) modifications to the ISO MPEG-4 AAC reference code were distributed under the GPL.

Other software

FAAC and FAAD2 are used in the following software products and

libraries A library is a collection of Book, books, and possibly other Document, materials and Media (communication), media, that is accessible for use by its members and members of allied institutions. Libraries provide physical (hard copies) or electron ...

: *

Avidemux Avidemux is a free and open-source software application for non-linear video editing and transcoding multimedia files. The developers intend it as "a simple tool for simple video processing tasks" and to allow users "to do elementary things in ...

video editing software. *

CDex CDex is a freeware software package for Digital Audio Extraction from Compact Disc, Audio CD (a so-called CD ripper) and audio format conversion for Microsoft Windows. It converts Compact Disc Digital Audio, CDDA tracks from a CD to standard com ...

uses FAAC encoder. *

supports AAC encoding through external library libfaac, and using its experimental native encoder. * fre:ac uses FAAC and FAAD2 for AAC support. *

GStreamer GStreamer is a Pipeline (computing), pipeline-based multimedia framework that links together a wide variety of media processing systems to complete complex workflows. For instance, GStreamer can be used to build a system that reads files in one f ...

multimedia framework uses FAAC and FAAD. *

MPlayer MPlayer is a free and open-source media player software application. It is available for Linux, OS X and Microsoft Windows. Versions for OS/2, Syllable Desktop, Syllable, AmigaOS, MorphOS and AROS Research Operating System are also available. A ...

uses FAAD2. *

VLC media player VLC media player (previously the VideoLAN Client) is a free and open-source software, free and open-source, software portability, portable, cross-platform media player software and streaming media Server (computing), server developed by the Vide ...

uses the FAAC (encoder) and FAAD (decoder) to provide support for AAC audio. *

Music Player Daemon Music Player Daemon (MPD) is a free software, free and Open-source software, open-source music player Server (computing), server. It plays audio files, organizes playlists and maintains a music database. In order to interact with it, a Client (co ...

uses FAAD2 * Music on Console uses FAAD2 There is also other software that uses FAAC libraries.

References