Abstract: A method and an apparatus for manipulating an input signal (e.g., an audio equivalent signal) having a specific length to form an output signal having a different length. A chain of successive overlapping time windows is positioned with respect to the input signal; segment signals are derived from the input signal and the segment signals; and the output signal is synthesized by chained superposition of a sequence of the segment signals. Each of the windows (except for the first window in the chain) is positioned by incrementing a position of the window from a corresponding position of a preceding window in the chain by a time interval. That time interval is substantially equal to a principal period of periodicity of a portion of the input signal with respect to which the window will be positioned. The sequence of segment signals is derived from the segment signals by performing at least one of repeating and suppressing one or more of the segment signals.

Abstract: Method and apparatus for manipulating an input signal (e.g. an audio (equivalent) signal) to obtain an output signal having a different pitch and/or duration. The method includes (a) positioning a chain of successive overlapping time windows with respect to the input signal; (b) deriving segments signals from the input signal and the windows; and (c) synthesizing the output signal by chained superposition of the segments signals. Each of the windows (except for the first window in the chain) is positioned by incrementing a position of the window from a corresponding position of a preceding window in the chain by a time interval. The time interval is substantially equal to a local pitch period for a portion of the input signal with respect to which the window is positioned. Accordingly, each of the windows of the chain (except for the first window) is positioned so that it begins at a predetermined time interval from a preceding window in the chain.