A Method for Long Extrapolation of Audio Signals

Abstract

A new method for a long extrapolation of audio signals is presented. The method is fast and can extrapolate several thousand samples of noisy audio signals. All the information for the extrapolation is taken from the signal itself, so that no additional knowledge about the signal content is required. The basic theory is presented and tested by simulation. The major problem for optimal extrapolation is the determination of the impulse response of the signal. Different methods to solve the impulse response are described. The requirements for the signals that can be extrapolated are studied. The ability of the method to extrapolate audio signals with different types of amplitude envelopes is studied and simulated. The fact that signals with exponential or polynomial amplitude envelopes can be extrapolated is proven. A mathematical measurement tool for the quality of the extrapolation is presented. The effect of noise on the extrapolation is also studied. The method is tested with real music signals.