A Laser Triangulation Approach for Optical Audio Reconstruction of Phonograph Records

Abstract: This thesis introduces a method for contact-free optical audio reconstruction of phonograph records using laser triangulation. The reconstruction is done using a 3D-profile camera and by scanning the surface of record in a single circumference. The depth-map created by the camera is then used to decode the audio information stored in the record. To evaluate the quality of the decoded audio information, it is tested against digital copies of the same record in order to analyze the correlation between it and the extracted sound. The result of this thesis presents a decoded and high correlated audio which is recognizable to an original digital copy. The method is well suited for fast real-time or faster than real-time decoding implementations.