Patent ID: 7705231

Claim:
A method for generating an accompaniment for a recorded audio melody, the method comprising: creating individual maior-key and minor-key chord transition matrices comprising learned chord transition probabilities based on each chord in a set of songs; creating individual maior-key and minor-key melody observation matrices comprising learned note duration probabilities based on each note in each chord in the set of songs; blending the maior-key and the minor-key chord transition matrices into a resultant chord transition matrix; and blending the maior-key and a minor-key melody observation matrices into a resultant melody observation matrix; providing a recorded audio melody that comprises segments; performing a frequency analysis of the recorded audio melody; summing the total duration of each fundamental frequency within a segment; based on the summing, computing a probability for each possible chord for each segment; based on the computed probabilities, selecting a set of chords for the segments wherein the selecting a set of chords comprises using a Hidden Markov Model that has been trained using the resultant chord transition matrix and the resultant melody observation matrix; and outputting the set of chords as an accompaniment for the recorded audio melody.