A method of coherent spatial filtering of optical sound records is proposed. Theoretical analysis shows that these methods provide suppression of scratch images and of worn sound track noise by 10–14 dB, i.e., to the level of a new sound record. It is shown that linear processing of a corrected image is inefficient, and only its nonlinear processing leads to an improved SNR. Three methods of realizing nonlinear transformation are suggested. Results of the experiment are in good agreement with theory.
© 1983 Optical Society of America
M. E. Zhabotinski, A. A. Lapides, and A. I. Shpuntov, "Coherent-optic suppression of scratch noise on optical sound records," Appl. Opt. 22, 4020-4027 (1983)