1. The method of identifying certain programs transmitted by a broadcasting station, wherein at least one predetermined and readily identifiable signalling event occurs in conjunction with the broadcast of ones of said programs, said method comprising the steps of: generating a digital reference feature set from ones of said programs by a transformation of at least one segment of a said program's analog signal content, said segment beginning at a predetermined time with reference to one of said signalling events and being of a predetermined duration; identifying by a label code the program from which each said reference feature set was derived; storing a set of said reference feature sets and said associated program label codes in a memory; detecting said signalling events within the broadcast signal of said broadcasting station; generating a digital broadcast feature set from ones of said programs broadcast by said broadcasting station, said broadcast feature set being generated by said transformation of at least one segment of the analog broadcast signal content, said segment beginning at a predetermined time with reference to one of said signalling events and being of a predetermined duration; comparing at least one said broadcast feature set to at least one said reference feature set to produce a recognition output when the degree of similarity between a broadcast feature set and a reference feature set meets a predetermined standard, the broadcast program from which said broadcast feature set was derived being identified by the program label code associated with said reference feature set.