Patent ID: 7518053

Claim:
A method of beat matching, comprising the steps of: (a) providing an input digital audio stream; (b) successively for each integer n=1, 2, . . . , N where N is an integer greater than 2: (i) providing an nth reference beat rate for an nth reference frame; (ii) detecting an nth input beat rate for an nth input frame of samples of said input digital audio stream; (iii) finding beat locations for said nth reference frame using said nth reference beat rate; (iv) finding beat locations in said nth input frame using said nth input beat rate; (v) computing an nth conversion ratio from said beat locations for said nth reference frame and said beat locations in said nth input frame; (vi) computing an nth hop number from the number of said beat locations for said nth reference frame and the number of said beat locations in said nth input frame; (vii) defining an nth hop window for said nth reference frame using said nth hop number; (viii) computing an nth set of output samples from samples of said nth input frame using said nth conversion ratio where the number of samples in said nth set of output samples corresponds to said nth hop window; (ix) determining an (n+1)th reference frame with beginning as following the end of said nth hop window; and (x) determining an (n+1)th input frame in said input audio stream by advancing in said input audio stream from the start of said nth input frame by a number of sample locations equal to the product of said nth conversion ratio multiplied by said number of locations corresponding to said nth hop window.