The MPEG audio
standard is a high-complexity, high-compression, and high audio quality algorithm. The
Motion Pictures Experts Group (MPEG), a group that works on standards for both audio and
video systems, saw the benefits of the digital representation of audio data. Its
advantages include high immunity to noise (interference that destroys the integrity of
signals), stability, reproducibility, and the efficient implementation of audio processing
functions through a computer.
MPEG is a working group that was formed from the existing JPEG
(Joint Photographic Experts Group) standard for bit reduction of still pictures. Its goal
is to devise a suitable encoding scheme for transmitting moving pictures and sound over
various broadcast links and recording them in standard digital storage media. Since moving
pictures are often accompanied by sound, MPEG also defined a standard for encoding audio
information. In 1992, a standard for audio and video encoding was devised known as MPEG-1.
MP3 stands for MPEG-1 Layer 3. Layers represent a family of coding algorithms. Layer 1
has the lowest complexity compared to the other layers. Layer 2 requires a more complex
encoder and decoder and is directed more towards different applications. Thus, Layer 2 is
more able than Layer 1 to remove the redundancy in the signal that takes up space. Layer 3
is again more complex and further reduces redundancy and relevance from the data. . The
layers are backwards-compatible, which means that any software or hardware capable of
decoding Layer 3 audio should also be able to decode Layers 1 and 2.
So why has MP3 emerged as the leading tool for Internet audio delivery? MPEG-1 Layer 3
is defined as an open standard, so the specification is available to anyone interested in
implementing the standard. Since no single company owns the standard, public example
source code is available and the format is well defined. Also, driven by the demand for
professional use, many MP3 encoders and decoders are readily available for use. This
simplifies and accelerates the adoption of MP3 technology. Additionally, the widespread
increase in usage of computers fast enough to decode audio, as well as increasingly fast
and widely available Internet access, has contributed to the embracing of MP3 music
format.