mp3英语介绍

What is MP3 MP3 full name is Moving Picture Experts Group , Audio Layer III one , technology used by it is third generation developing out on compression technology in VCD (MPEG-1) VF , but not MPEG-3. MP3 is one kind of the international technical norms that VF compresses , start from 1980 age medium term (1987), before Germany Erlangen Fraunhofer research institute begin code studying the sound concentrating efforts on height mass , low data rates. Be in DietUnder Seitzer help of Germany professor of university, 1989, Fraunhofer patent being obtained permission to have got MP3 in Germany, the quilt submits almost annual last this technology to International Standards Organization (ISO) , integrates to have entered the MPEG-1 standard. The MPEG sound standard provides independent three compression arrangement of ideas: 1 tier of (1, tier of Layer) 2 (Layer 2) composes in reply 3 tier of (Layer 3), the consumer may be on the march between complexity and sound quality judging to the arrangement of ideas choice. (1) 1's tier of coders are Complicated 2's tier of coders degree is medium (2) , the coder data-out rates are 256 kb/s ~ 192 kb/s, the person applies including that the figure broadcasts sound (digital broadcast audio , DBA) , figure music , CD-I (compact disc-interactive) and VCD (video compact disc) etc.3's tier of coders are most complicated (3) , the coder data-out leads being 64 kb/s, apply to upper voice transmission of ISDN mainly. Mpeg-1 lay 3 support sampling rate are 32 , 44.1 , 48 khz , lead bit supporting 32- - - 320 kbps Mpeg-2 lay 3 support sampling rate to be 16 , 22.05 , 24 khz , lead bit supporting 8- - - 160 kbps Fraunhofer to be unable to be in progress extended to here, with it truns out that again, sampling rate supported by MPEG-2 gets rid of with 2 : 8 , 11.025, and 12 kHz, bit of rates and MPEG-2 are identical , are called \" MPEG 2.5 ". M