Musical pitch tracking based on a pattern recognition algorithm Free

It can be shown that, when the Fourier transform is plotted against log frequency, the pattern obtained in the frequency domain is the same for any sound with harmonic frequency components. A constant Q Fourier transform has been calculated for frequencies corresponding to a musical quarter tone and plotted against log frequency. The resulting pattern can be “tracked” using cross correlation to give the musical pitch. Excellent results have been obtained for a variety of instruments including the violin, flute, and piano. [Work supported by a Brachman Hoffman Fellowship from Wellesley College.]