Difference between revisions of "Advanced Audio Coding"
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{{wikipedia|Advanced Audio Coding}} | {{wikipedia|Advanced Audio Coding}} | ||
| − | AAC is a | + | AAC is a set of codecs designed to provide better compression than [[MP3]]s, and are improved versions of [[MPEG]] audio. |
| − | AAC has many | + | AAC has many options and profiles available. |
| + | |||
| + | == Introduction == | ||
| + | AAC actually refers to two similar codecs - MPEG-2 AAC and MPEG-4 AAC. It has many options and is heavily customisable depending on the desired output | ||
It has some advantages over MP3 - it has a greater range of sample frequencies, up to 48 channels and higher coding efficiency. It also has much better handling of frequencies above 16 kHz. | It has some advantages over MP3 - it has a greater range of sample frequencies, up to 48 channels and higher coding efficiency. It also has much better handling of frequencies above 16 kHz. | ||
| + | Depending on the AAC profile and the MP3 encoder, 96 kbit/s AAC can give nearly the same or better perceptional quality as 128 kbit/s MP3. | ||
| + | |||
| + | MPEG-4 AAC is used by [[iTunes]] and [[iPod]] (see also [http://www.apple.com/mpeg4/aac Apple webpage on AAC]) and most of the portable devices. | ||
| + | |||
| + | == Profiles and extensions == | ||
| − | + | '''High Efficiency AAC''' (aka '''aacPlus'''), is a [[lossy]] data compression scheme for audio streams, and is part of the '''[[MPEG-4]] Part 3''' specification. | |
| − | + | HE-AAC combines [[Advanced Audio Coding]] (AAC), [[Spectral Band Replication]] (SBR) and, since version 2 (or Enhanced aacPlus), [[parametric stereo]] (PS). The [[codec]] can operate at very low bitrates and is good for [[internet radio]] streaming. A 48 kilobit-per-second stream is considered to have higher quality than 128 [[kbit/s]] [[MP3]]. | |
| − | + | VLC supports HE-AAC through the [[FAAD2]] library. | |
VideoLAN uses the [[FAAC]] (encoder) and [[FAAD]] (decoder) to provide support for AAC audio. | VideoLAN uses the [[FAAC]] (encoder) and [[FAAD]] (decoder) to provide support for AAC audio. | ||
| − | + | {{codec audio|mod=faad2}} | |
| + | {{wikipedia|HE-AAC}} | ||
| + | |||
| + | ==External links== | ||
| + | * [http://www.tuner2.com/ Tuner2.com] list of Internet radio stations using aacPlus | ||
| + | * [http://www.codingtechnologies.com/products/aacPlus.htm aacPlus explained] | ||
| + | * [http://sourceforge.net/projects/faac/ Freeware Advanced Audio Coder] FAAC(encoder) and FAAD2 (decoder) | ||
== Related Links == | == Related Links == | ||
* [[HE-AAC]] | * [[HE-AAC]] | ||
* [http://www.audiocoding.com/ FAAC and FAAD] | * [http://www.audiocoding.com/ FAAC and FAAD] | ||
Revision as of 13:16, 28 June 2012
AAC is a set of codecs designed to provide better compression than MP3s, and are improved versions of MPEG audio.
AAC has many options and profiles available.
Introduction
AAC actually refers to two similar codecs - MPEG-2 AAC and MPEG-4 AAC. It has many options and is heavily customisable depending on the desired output
It has some advantages over MP3 - it has a greater range of sample frequencies, up to 48 channels and higher coding efficiency. It also has much better handling of frequencies above 16 kHz. Depending on the AAC profile and the MP3 encoder, 96 kbit/s AAC can give nearly the same or better perceptional quality as 128 kbit/s MP3.
MPEG-4 AAC is used by iTunes and iPod (see also Apple webpage on AAC) and most of the portable devices.
Profiles and extensions
High Efficiency AAC (aka aacPlus), is a lossy data compression scheme for audio streams, and is part of the MPEG-4 Part 3 specification.
HE-AAC combines Advanced Audio Coding (AAC), Spectral Band Replication (SBR) and, since version 2 (or Enhanced aacPlus), parametric stereo (PS). The codec can operate at very low bitrates and is good for internet radio streaming. A 48 kilobit-per-second stream is considered to have higher quality than 128 kbit/s MP3.
VLC supports HE-AAC through the FAAD2 library.
VideoLAN uses the FAAC (encoder) and FAAD (decoder) to provide support for AAC audio.
??
|
This is an audio codec. The name to use at the command line is unknown. This codec is from the faad2 module. |
External links
- Tuner2.com list of Internet radio stations using aacPlus
- aacPlus explained
- Freeware Advanced Audio Coder FAAC(encoder) and FAAD2 (decoder)
