Chord detection algorithms?

Question

I am developing software that depends on musical chords detection. I know some algorithms for pitch detection, with techniques based on cepstral analysis or autocorrelation, but they are mainly focused on monophonic material recognition. But I need to work with some polyphonic recognition, that is, multiple pitches at the same time, like in a chord; does anyone know some good studies or solutions on that matter?

I am currently developing some algorithms based on the FFT, but if anyone has an idea on some algorithms or techniques that I can use, it would be of great help.

Answer 1

This post is a bit old, but I thought I'd add the following paper to the discussion:

Klapuri,Anssi; Multipitch Analysis of Polyphonic Music and Speech Signals Using an Auditory Model; IEEE TRANSACTIONS ON AUDIO, SPEECH, AND LANGUAGE PROCESSING, VOL. 16, NO. 2, FEBRUARY 2008 255

The paper acts somewhat like a literature review of multipitch analysis and discusses a method based on an auditory model:

(The image is from the paper. I don't know if I have to get permission to post it.)