time stretch lib for sound

[Cor]

Needed lib for change speed of sound without changing the pitch.

Anyone?

EDIT:

http://www.surina.net/soundtouch/index.html

and

http://sourceforge.net/projects/libmpg123/

android application uses this lib: AudioSpeedChanger

https://market.android.com/details?id=gabriel.audioslower.lite&feature=search_result

Can this be converted to B4A?. This will be great for all musicians