How to detect sound frequency for particular sound in iphone?

Question

I\'m doing an app where I want to detect sound frequency. How to detect frequency for particular sound like dog sound? Does anybody have tutorial or some sample codes?

Answer 1

Detecting a single frequency, or even computing a single FFT, is not a reliable method for differentiating a dog bark from other common sounds of around the same volume.

What might work is sound fingerprint analysis using MFCC's, followed by statistical pattern matching against a large enough "dog" sound database. Some pointers to the type of signal processing required might be answered here: Music Recognition and Signal Processing

This is non-trivial stuff more suited for multiple college textbook chapters than any short tutorial.

Answer 2

To detect the frequency, you can use a pitch detection algorithm like FFT.

Learn more here: http://en.wikipedia.org/wiki/Pitch_detection_algorithm

You can look at this project for working source code for iOS that uses FFT algorithm to detect frequencies: https://github.com/hollance/SimonSings