RESTORATION OF NONLINEARLY DISTORTED AUDIO WITH THE APPLICATION TO OLD MOTION-PICTURES

摘要

In this paper a robust and efficient method is presented for restoration of nonlinearly distorted movie soundtracks. The method is based on the a priori knowledge of the shape of the nonlinear function, which is assumed to be a static nonlinearity. The original undistorted signal is modeled by a set of harmonically related sinusoids. This signal is led through the model of the nonlinear function. The parameters of the model are determined by minimizing the difference of the modeled distorted signal and the signal of the movie soundtrack. Tikhonov regularization is applied to avoid noise intensification during the restoration process. The proposed method has been successfully applied to old motion-picture audio tracks.