Global InformationMP3 information
 | |
| Filename extension | .mp3.bit (before 1995)[1] |
|---|---|
| Internet media type |
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| Developed by | Karlheinz Brandenburg, Ernst Eberlein, Heinz Gerhäuser, Bernhard Grill, Jürgen Herre and Harald Popp (all of Fraunhofer Society),[5] and others |
| Initial release | 6 December 1991[6] |
| Latest release | ISO/IEC 13818-3:1998 April 1998 |
| Type of format | Lossy audio |
| Contained by | MPEG-ES |
| Standards |
|
| Open format? | Yes[9] |
| Free format? | Expired patents[10] |
MP3 (formally MPEG-1 Audio Layer III or MPEG-2 Audio Layer III)[4] is a coding format for digital audio developed largely by the Fraunhofer Society in Germany under the lead of Karlheinz Brandenburg,[11][12] with support from other digital scientists in other countries. Originally defined as the third audio format of the MPEG-1 standard, it was retained and further extended—defining additional bit rates and support for more audio channels—as the third audio format of the subsequent MPEG-2 standard. A third version, known as MPEG-2.5—extended to better support lower bit rates—is commonly implemented but is not a recognized standard.
MP3 (or mp3) as a file format commonly designates files containing an elementary stream of MPEG-1 Audio or MPEG-2 Audio encoded data, without other complexities of the MP3 standard.
Concerning audio compression (the aspect of the standard most apparent to end-users and for which it is best known), MP3 uses lossy data compression to encode data using inexact approximations and the partial discarding of data. This allows a large reduction in file sizes when compared to uncompressed audio. The combination of small size and acceptable fidelity led to a boom in the distribution of music over the Internet in the mid-to-late 1990s, with MP3 serving as an enabling technology at a time when bandwidth and storage were still at a premium. The MP3 format soon became associated with controversies surrounding copyright infringement, music piracy, and the file-ripping and sharing services MP3.com and Napster, among others. With the advent of portable media players, a product category also including smartphones, MP3 support remains near-universal.
MP3 compression works by reducing (or approximating) the accuracy of certain components of sound that are considered (by psychoacoustic analysis) to be beyond the hearing capabilities of most humans. This method is commonly referred to as perceptual coding or psychoacoustic modeling.[13] The remaining audio information is then recorded in a space-efficient manner using MDCT and FFT algorithms. Compared to CD-quality digital audio, MP3 compression can commonly achieve a 75–95% reduction in size. For example, an MP3 encoded at a constant bit rate of 128 kbit/s would result in a file approximately 9% the size of the original CD audio.[14] In the early 2000s, compact disc players increasingly adopted support for playback of MP3 files on data CDs.
The Moving Picture Experts Group (MPEG) designed MP3 as part of its MPEG-1, and later MPEG-2, standards. MPEG-1 Audio (MPEG-1 Part 3), which included MPEG-1 Audio Layer I, II, and III, was approved as a committee draft for an ISO/IEC standard in 1991,[15][16] finalized in 1992,[17] and published in 1993 as ISO/IEC 11172-3:1993.[7] An MPEG-2 Audio (MPEG-2 Part 3) extension with lower sample and bit rates was published in 1995 as ISO/IEC 13818-3:1995.[8][18] It requires only minimal modifications to existing MPEG-1 decoders (recognition of the MPEG-2 bit in the header and addition of the new lower sample and bit rates).
- ^ Cite error: The named reference
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rfc5219was invoked but never defined (see the help page). - ^ "The mp3 team". Fraunhofer IIS. Retrieved 12 June 2020.
- ^ Patel K, Smith BC, Rowe LA (1 September 1993). "Performance of a software MPEG video decoder". Proceedings of the first ACM international conference on Multimedia - MULTIMEDIA '93. ACM Multimedia. New York City: Association for Computing Machinery. pp. 75–82. doi:10.1145/166266.166274. ISBN 978-0-89791-596-0. S2CID 3773268. Reference 3 in the paper is to Committee Draft of Standard ISO/IEC 11172, December 6, 1991.
- ^ a b Cite error: The named reference
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13818-3was invoked but never defined (see the help page). - ^ "MP3 technology at Fraunhofer IIS". Fraunhofer IIS. Archived from the original on 15 August 2021. Retrieved 12 June 2020.
- ^ MP3 (MPEG Layer III Audio Encoding) (Full draft). Sustainability of Digital Formats. Washington, D.C.: Library of Congress. 3 May 2017. Retrieved 1 December 2021.
- ^ "73. "Father" of the MP3, Karlheinz Brandenburg" – via www.youtube.com.
- ^ "On the 20th Birthday of the MP3, An Interview With The "Father" of the MP3, Karlheinz Brandenburg".
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