The full name of MP3 is Moving Picture Experts Group Audio Layer III. Simply put, MP3 is an audio compression technology, because the compression of the full name called MPEG Audio Layer3, so it is referred to as MP3. MP3 is the use of MPEG Audio Layer 3 technology, the music to 1:10 or even 1:12 compression rate, compressed into smaller capacity file, in other words, MP3 in the case of small loss of sound quality of the file to a more compressed Small degree. But also very good to maintain the original sound quality. It is because MP3 small size, high quality features make MP3 format almost become synonymous with online music. Every minute music MP3 format is only about 1MB in size, so that the size of each song is only 3-4 megabytes. Use MP3 player MP3 files in real-time decompression (decoding), so that high-quality MP3 music to play out.
MP3 on the audio signal using a "lossy compression" approach, that is, MP3 this part of the sound removed, making the file size greatly reduced, but in the human ear sounds, but there is no distortion. Technically speaking, in order to reduce the distortion of the sound, the MP3 takes the spectrum analysis of the audio file first, filters the insensitive level and noise level with the filter, and then quantifies the remaining A rearrangement, MP3 and finally the formation of a higher compression ratio, small MP3 files, and the sound quality is only a small loss.
Because MP3 is only compressed using the encoding, before playing or to restore this compressed code to play. In addition, MP3 there is a very important feature, is not to provide copyright protection, which makes this format music quickly on the Internet a lot of popular and spread, MP3 play software also appeared in a large number and became popular, but also triggered Many copyright disputes. Italian-born LeonardoChiariglione is the founder of MPEG, because MPEG released MP3 audio format, Chiariglione was also known as the father of MP3 (the other is the aforementioned German Brandenhurg), he later presided over the launch of the "Digital Music Security Action Plan (Secure Digita Music Initiative: SDMI) is committed to solving and coordinating issues related to digital music copyright.
MP3 is the use of human ear on the high-frequency sound signal is not sensitive to the characteristics of the time domain waveform signal into frequency domain signal, and divided into multiple frequency bands, MP3 the use of different frequency bands of different compression rate, high frequency increase compression ratio (Or even ignore the signal) on the low-frequency signal using a small compression ratio to ensure that the signal is not distorted. This is equivalent to abandon the human ear can not hear the high-frequency sound, MP3 only to retain the low-frequency part can be heard, so the sound with 1:10 or even 1:12 compression rate compression. Because of this compression method called MPEG Audio Player3, so it is referred to as MP3.
According to the MPEG specification, the AAC (Advanced audio coding) in MPEG-4 will be the next generation of MP3 format. MP3 is also divided into headphones MP3 and putting MP3 two categories, MP3 the traditional MP3 need to have a good sound quality with headphones, but people hurt the eardrum, the new MP3 is the main direction of putting MP3, almost no eardrum Hurt, so as to get people's favorite.