Patent ID: 7649823
Filing Date: 2010-01-19
Classification: G10H,G11B

Abstract:
1. A method for reproducing digital codes at irregular intervals from pieces of data information and pieces of meaningless information stored in an information storage medium, comprising the steps of: a) producing an analog data signal continuously varying a physical quantity from said pieces of data information and said pieces of meaningless information stored in said information storage medium; b) converting said analog data signal to a data stream containing said digital codes expressing discrete values of said physical quantity and synchronous data codes expressing a discrete value representative of said pieces of meaningless information through a demodulation technique corresponding to a modulation technique assigning values of said digital data codes to values of physical quantity that is periodically varied; said step b) includes the sub-steps of c) eliminating said synchronous data codes from said data stream so as to leave said digital data codes representative of said pieces of data information at said irregular intervals.