About the MP3 compression
MP3 is an audio-specific format that involves compression.
MP3 removes certain parts of sound that are out of the hearing range of most people. It provides a representation of pulse-code modulation, which is encoded audio in a considerably less space than using straightforward methods. It uses psychoacoustic models to discard those components that are less audible to human hearing and records the remaining information in an efficient manner, similar to how JPEG works.
The psychoacoustic masking codec was first proposed independently by MA Krasner in the US and Manfred Schroeder in Germany. The immediate predecessor of the Mp3 and its first practical implementation was an implementation of psychoacoustic transform coder on Motorola 56000 chips called Optimum Coding in the Frequency Domain or OCF.
MP3 was a direct descendant of that system. Modern lossy bit compression technologies, including MPEG and MP3, are based on the early work of Oscar Bonello of Argentina. He was involved in studio equipment design for broadcast radio automation.
In 1983, he started researching the idea of Critical Band Masking principle in order to reduce the amount of bit stream necessary to encode an audio signal.
He created, in 1987 into the word’s first bit compression system named ECAM.