Apple AAC: Difference between revisions
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[[AAC]] encoders and is also another commercial AAC implementation. The current version of Quicktime supports [[Multichannel]] encoding up to 8 channels, and HE-AAC v1 with [[SBR]]. | [[AAC]] encoders and is also another commercial AAC implementation. The current version of Quicktime supports [[Multichannel]] encoding up to 8 channels, and HE-AAC v1 with [[SBR]]. | ||
Although this | Although this part of the commercial QuickTime Proe, VBR and CBR modes are available for free | ||
through [http://www.apple.com/itunes/ iTunes] (with a maximum [[sampling rate]] of 44.1khz for iTunes 10+ and 48khz for [http://www.oldapps.com/itunes.php?old_itunes=61 iTunes 9-]) | |||
Free Third-party interfaces such as [http://sites.google.com/site/qaacpage/ qAAC] expose more modes such as TVBR (equivalent to quality modes in other encoders) and CVBR ("constrained VBR") | Free Third-party CLI interfaces such as [http://sites.google.com/site/qaacpage/ qAAC] expose more modes such as TVBR (equivalent to quality modes in other encoders) and CVBR ("constrained VBR") | ||
In recent tests for [http://listening-tests.hydrogenaudio.org/igorc/results.html 64kbps HE-AAC] and [http://listening-tests.hydrogenaudio.org/igorc/aac-96-a/results.html 96kbps LC-AAC] Quicktime has consistently come out near the top. This also applies to higher bitrates such as 128kbps and is likely to apply to higher bitrates such as 160kbps and beyond. | |||
In recent tests for [http://listening-tests.hydrogenaudio.org/igorc/results.html 64kbps HE-AAC] and [http://listening-tests.hydrogenaudio.org/igorc/aac-96-a/results.html 96kbps LC-AAC] Quicktime has consistently come out near the top. | |||
In 2009, the core AAC encoding algorithm was updated with "higher fidelity". The bitrate distribution algorithm was also changed. | In 2009, the core AAC encoding algorithm was updated with "higher fidelity". The bitrate distribution algorithm was also changed. | ||
==External links== | |||
*[http://www.apple.com/quicktime Apple's Quicktime Website] | |||
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Revision as of 07:41, 17 September 2011
QuickTime AAC is known to be one of the highest quality medium-bitrate CBR and VBR LC AAC encoders and is also another commercial AAC implementation. The current version of Quicktime supports Multichannel encoding up to 8 channels, and HE-AAC v1 with SBR.
Although this part of the commercial QuickTime Proe, VBR and CBR modes are available for free through iTunes (with a maximum sampling rate of 44.1khz for iTunes 10+ and 48khz for iTunes 9-)
Free Third-party CLI interfaces such as qAAC expose more modes such as TVBR (equivalent to quality modes in other encoders) and CVBR ("constrained VBR")
In recent tests for 64kbps HE-AAC and 96kbps LC-AAC Quicktime has consistently come out near the top. This also applies to higher bitrates such as 128kbps and is likely to apply to higher bitrates such as 160kbps and beyond.
In 2009, the core AAC encoding algorithm was updated with "higher fidelity". The bitrate distribution algorithm was also changed.
External links
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