SIGNAL PROCESSING METHODS FOR THE RECOVERY OF AUDIO FROM EARLY ACOUSTIC CYLINDER RECORDINGS, MEASURED VIA NON-CONTACT OPTICAL SENSOR

摘要

A non-contact method for the recovery of audio signals from early acoustic cylinder recordings is presented. The cylinder surface is scanned via optical displacement sensor, capable of submicron axial resolution. Sound recovery is achieved by estimating the trajectory of a playback stylus over the measured surface. The processing methods required to extract audio from a discrete height map are described. The signal to noise ratio of the extracted signal as a function of position across the groove cross-section is examined, for a Blue Amberol cylinder, (circa 1912).