Production Glossary
MP3
MP3, known officially as MPEG-1, Layer 3, is a compressed digital audio file that is capable of shrinking audio files by nearly 90%. MP3 conforms to a standard set by the Motion Pictures Experts Group (MPEG), utilizing a method known as psychoacoustic modeling. Psychoacoustic modeling eliminates digital bits that correlate to sounds that are unable to be heard by the human ear. Technically, MP3 is a form of lossy compression because the data that is thrown out cannot be retrieved once the file is uncompressed. But, MP3 can also be considered lossless in the sense that the sounds that are deleted are not missed by the listener if the file is encoded properly.MP3’s primary benefit is that it requires less storage space due to its smaller bit rates, but if the bit rate dips below 128 kbps the sound becomes compromised. A technique known as joint stereo is used to increase the sound quality by joining, when possible, similar sounds from the right and left tracks.
