# Finding the frequencies given in a wav file

I have a wav file containing a series of chords, each containing 3 or 4 notes, played concurrently.

I need to find the frequencies of each note in each chord, and I can use matlab to do any computation.

Currently I think I need to find the spectrogram of the wav file and convert the frequencies from normailsed frequencies to normal frequencies (I know the sampling rate). Here is the spectrogram:

Is this a good approach to solving this problem?

I've already tried it, but the spectrogram isn't particularly informative. Is there an alternative method that I'm ignoring?

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Are you allowed to process the chords seperatley? –  Deve Jan 14 '13 at 17:30
There's no restrictions like that, no. I guess I could use a window to isolate each chord and then find the spectrum. –  Tom Kealy Jan 14 '13 at 17:47