Now my work is to make an android app,it can detect the frequecy,volume size and duration of a sound.That I do not know where to start,and I do not find any useful materials ,anyone can help me.Couled you provid a demo for me.
very thanksful for your replay.And I am sorry for my poor English.
You might want to have a look at code.google.com/p/musicg/
library which is very useful in manipulating sounds. As per your requirement you can calculate frequency and other oarameters go through its API.