MP3 is an audio-specific compression format. It provides a representation of pulse-code modulation-encoded audio in much less space than straightforward methods, by using psychoacoustic models to discard components less audible to human hearing, and recording the remaining information in an efficient manner. The MP3 format uses a hybrid transformation to transform a time domain signal into a frequency domain signal:
+ 32-band polyphase quadrature filter
+ 36 or 12 tap MDCT; size can be selected independent for sub-band 0...1 and 2...31
+ Aliasing reduction postprocessing
+ MP3 audio can be compressed with different bit rates, providing a range of tradeoffs between data size and sound quality.
The MPEG specifications support AAC (Advanced audio coding) from MPEG-4 as MP3's successor, although other new audio formats have also achieved similar usage levels. However, MP3's extreme popularity makes it secure in its dominant position for the near future, with support from a huge range of software and hardware, including portable MP3 players and even some DVD and CD players. The large MP3 collections that many individuals have amassed will also ensure its longevity, in the same way as with any physical medium.
+ 32-band polyphase quadrature filter
+ 36 or 12 tap MDCT; size can be selected independent for sub-band 0...1 and 2...31
+ Aliasing reduction postprocessing
+ MP3 audio can be compressed with different bit rates, providing a range of tradeoffs between data size and sound quality.
The MPEG specifications support AAC (Advanced audio coding) from MPEG-4 as MP3's successor, although other new audio formats have also achieved similar usage levels. However, MP3's extreme popularity makes it secure in its dominant position for the near future, with support from a huge range of software and hardware, including portable MP3 players and even some DVD and CD players. The large MP3 collections that many individuals have amassed will also ensure its longevity, in the same way as with any physical medium.
