Can use Kaiser-Bessel derived window function to eliminate spectral leakage at the expense of widening the main lobe.Higher coding accuracy for transient signals (AAC uses a blocksize of 128 or 120 samples, allowing more accurate coding than MP3's 192 sample blocks).Higher coding efficiency for stationary signals (AAC uses a blocksize of 1024 or 960 samples, allowing more efficient coding than MP3's 576 sample blocks).Higher efficiency and simpler filterbank (rather than MP3's hybrid coding, AAC uses a pure MDCT).Standardized constant bit rate with bit reservoir. Arbitrary bit-rates and variable frame length.Up to 48 channels (MP3 supports up to two channels in MPEG-1 mode and up to 5.1 channels in MPEG-2 mode).More sample frequencies (from 8 kHz to 96 kHz) than MP3 (16 kHz to 48 kHz).The AAC format was designed to be an improvement over MP3 in the following aspects: MP3 offers lower quality than AAC at the same bitrate. However, not as popular as MP3ĪAC offers better quality than MP3 at the same bitrate, even though AAC also uses lossy compression. Part 7 of the MPEG-2 standard, and Subpart 4 in Part 3 of the MPEG-4 standard.
Virtually all music players support MP3 files.Īudio/aac, audio/aacp, audio/3gpp, audio/3gpp2, audio/mp4, audio/MP4A-LATM, audio/mpeg4-genericĪAC was developed with the cooperation and contributions of companies including Fraunhofer IIS, AT&T Bell Laboratories, Dolby, Sony Corporation and NokiaĪ group of engineers from Europe, belonging to Philips, CCETT (Centre commun d'études de télévision et télécommunications), IRT and Fraunhofer Society However, not all music players support AAC files. aacĪpple has promoted AAC - all iPods and iPhones play AAC files.
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