What an Mp3 exactly is
What an Mp3 exactly is
Waling along a street leisurely, sing along your favorite songs, music permeate your world. An mp3 player is convenient for us to enjoy music. It is so small and exquisite, and also provides more songs than CD play, the tone is prefect, even though you can enjoy jazz and popular style at the same time. How miraculous it is, do you know what it exactly is?
An MP3 is a digital audio file compressed with a standard defined by the Motion Pictures Experts Group (MPEG). MPEG was formed to develop techniques for dealing with digital video; since most video also contains audio, MP3 was developed as an audio extension of that work. Officially known as 'MPEG-1, Layer 3?, MP3 is a lossy compression algorithm that uses psychoacoustic modeling to reduce the size of audio files by up to 90%.
Psychoacoustics takes advantage of deficiencies in the human hearing system to throw away digital bits corresponding to sounds that cannot be heard. The human ear cannot hear soft sounds in the presence of loud sounds having a similar frequency; for example, a voice conversation becomes inaudible when a jet flies low overhead. This effect is known as auditory masking, and done correctly the discarded sounds will not be missed.
MP3 player is a lossy algorithm in the sense that the original bits cannot be recreated from the compressed bits. In terms of hearing, however, MP3 is lossless because the human ear cannot distinguish between a CD recording and a properly encoded MP3 version of it. MP3s achieve this transparency at a bit rate of approximately 256 kilobits per second, or roughly one sixth of the 1.4 megabits per second required by the compact disc format.
MP3s can be recorded at lower bit rates, saving even more space, but audible differences begin to appear at rates below 128 kilobits per second. At these lower bit rates, MP3 can use a trick known as joint stereo to improve quality. Audio generally consists of left and right audio tracks. Joint stereo combines, whenever possible, the sounds common to both left and right tracks into one track. Instead of left and right, it has 'common' and 'different' channels.
Everyday can become a wonderful day with an mp3, young people like mp3. MP3 is fashionable, and new style is changed quality, don't make you a old-fashion boy or girl, the latest style is waiting for you to choose, let's following the fashion and be a fashionable young. Welcome to our online shop ipodstores.org, there are various digital camcorders and mp3, hurry up and go to buy now.
Internet reference: http://podcampchi.com/?p=60
Editor: Kim
About the Author:
