Abstract: A photosensitive medium, such as motion picture film, having digital data in multiple formats and analog audio signals photographically recorded thereon, and a system for photographically recording digital data (preferably including digital audio bits) in multiple formats and optionally also analog audio signals on a medium. Preferably, two digital soundtracks are recorded on the film, each in an array of bit areas arranged in row and column order, with the bit areas of one soundtrack between consecutive pairs of sprocket holes along one edge of the film, and the bit areas of the other soundtrack along the film edges outside the sprocket holes. Preferred embodiments of the invention include a camera assembly through which a motion picture film translates in real time.

Abstract: An audio data readout device for a motion picture film and a clock generating device in a changeover system for a motion picture film. First and second clock generating circuits generate first and second clocks of predetermined frequencies based upon a repetition frequency of perforations detected by first and second film readers and a repetition frequency of a track pitch of audio data, and route the resulting clocks to a changeover switch. At a changeover time, a changeover controller switchingly controls the changeover switch to select the second clock. A system clock generating circuit has loop characteristics of a longer time constant than the first or second clock generating circuits and smoothly locks the second clock to generate a system clock which is outputted. A stable and accurate system clock can be generated and outputted even when film running is unstable at the changeover time.