Si tratta di uno standard di compressione dell'audio con particolare attenzione all'efficienza e alla musica.

E' una compressione che perde in qualita', ma i file sono piu' piccoli di tre volte di un normale mp3, con la stessa qualita'.

Utilissimo, direi indispensabile, per lo streaming on line, perche' utilizza molta meno banda.

Usato da Real networks e aol, e' supportato anche da Winamp.

Una raccolta di programmi e' disponibile su: https://www.audiocoding.com/modules/wiki/?page=HE+AAC

"MPEG-4 aacPlus is the combination of three MPEG technologies comprising Advanced Audio Coding (AAC), coupled with Coding Technologies' Spectral Band Replication (SBR), and Parametric Stereo (PS) technologies. SBR is a unique bandwidth extension technique which enables audio codecs to deliver the same quality at half the bit rate. PS significantly increases the codec efficiency a second time for low bit rate stereo signals. "

Ma anche: "High-Efficiency AAC" is the official MPEG name for the combination of AAC and Spectral Band Replication / SBR since becoming an ISO/IEC International standard in May 2003. Other synonyms for this low bitrate tool are aacPlus, the trademark of the developing company Coding Technologies or AAC+, an unofficial shorter form used as a general description and also BWE / Bandwidth Extension used in some MPEG documents. See also MPEG-4 Audio Version 3 for more explanations, because this is another MPEG term for the different developing stages of their MPEG-4 multimedia standard.

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