Coded record and methods of and apparatus for encoding and decoding records

Abstract From the Canadian patent

Abstract of the Disclosure A novel record with alternate width modulated bars and spaces is decoded by comparing the width of each bar or space with a pair of reference values based on the product and quotient of a constant and the width of another bar or space to establish bit value. When the width value is greater or less than the reference value, the bit value is established. When the width values lie between the reference values a, state of equality is established which is resolved into a bit value by reference to the results of a prior or subsequent comparison. A system embodying the method includes storage means for storing width values, reference registers for establishing successive …