How to extract the basic info from an audio file?

Hi everyone I want to extract an audio file's basic information in my application. Like the iTunes ,when importing a song, the song's information (for example,Name ,Time ,Artist, Album ,Genre,Rating...) is extracted from the audio file. How to do it? Is there any API about it ?

How to implement quick-playing and slow-playing of sound file?

Hi All, I am developing an application which implement the playing of sound file. Now I want to change the rate of the sound when it is playing.In other words ,I want to implement quick-playing and slow-playing of the sound file.Is there any API for the function? Or can any one tell me any clue