Body energy as a power source

Smartphones, MP3 players, sports electronics devices such as pulse meters or trackers, medical equipment such as tonometers, pacemakers of the heart, or insulin pumps: An increasing number of electronic companions make daily ...

The iPod zombies are more social than you think

Teenagers get a bad rap for zoning out on their iPods at every given opportunity, but they may not be the unsociable narcissists they are often portrayed as. In fact, they are often skilled users who manage their devices ...

Intel's mysterious TV device sparks industry chatter

Buzz is building over Intel's secretive TV set-top box due out later this year, which the chipmaker claims will provide live and other content via the Internet, is easy to use, and boasts face-recognition technology so it ...

How quantum physics democratised music

Surprising connections between very different areas of physics and unexpected spin-offs from theory were explored by quantum physicist Prof. Sir Michael Berry in a lecture entitled "How quantum physics democratised music" ...

MP3 song-searching can increase risk for drivers

Consumers are increasingly using MP3 players in their vehicles, and auto makers have responded: Data show that 90% of new vehicles sold in the United States have MP3 connectivity. Makers of aftermarket MP3 controllers are ...

Jobs had Google phones in crosshairs: biographer

Insights into Apple co-founder Steve Jobs's vendetta against Google and his criticisms of fellow high-tech titans spread quickly online ahead of the Monday release of his authorized biography.

page 1 from 4

MP3

MPEG-1 or MPEG-2 Audio Layer III, more commonly referred to as MP3, is a patented digital audio encoding format using a form of lossy data compression. It is a common audio format for consumer audio storage, as well as a de facto standard of digital audio compression for the transfer and playback of music on digital audio players.

MP3 is an audio-specific format that was designed by the Moving Picture Experts Group (MPEG) as part of its MPEG-1 standard and later extended in MPEG-2 standard. The first MPEG subgroup – Audio group was formed by several teams of engineers at Fraunhofer IIS, University of Hannover, AT&T-Bell Labs, Thomson-Brandt, CCETT, and others. MPEG-1 Audio (MPEG-1 Part 3), which included MPEG-1 Audio Layer I, II and III was approved as a committee draft of ISO/IEC standard in 1991, finalised in 1992 and published in 1993 (ISO/IEC 11172-3:1993). Backwards compatible MPEG-2 Audio (MPEG-2 Part 3) with additional bit rates and sample rates was published in 1995 (ISO/IEC 13818-3:1995).

The use in MP3 of a lossy compression algorithm is designed to greatly reduce the amount of data required to represent the audio recording and still sound like a faithful reproduction of the original uncompressed audio for most listeners. An MP3 file that is created using the setting of 128 kbit/s will result in a file that is about 1/11 the size than the CD file created from the original audio source. An MP3 file can also be constructed at higher or lower bit rates, with higher or lower resulting quality.

The compression works by reducing accuracy of certain parts of sound that are considered to be beyond the auditory resolution ability of most people. This method is commonly referred to as perceptual coding. It uses psychoacoustic models to discard or reduce precision of components less audible to human hearing, and then records the remaining information in an efficient manner.

This text uses material from Wikipedia, licensed under CC BY-SA