Method and apparatus for automatically identifying a program including a sound signal

A monitoring device for use in collecting information for estimating an audience for widely disseminated audio information while carried on the person of an individual audience member, said widely disseminated audio information including an inaudible identification code indicating a source thereof and included within at least one band of frequencies of said widely disseminated audio information by modulating an energy level of a component of a digitized sound signal within said at least one band of frequencies, comprising:

• an enclosure;
• means for attaching the enclosure to the person of an individual audience member;
• transducer means for converting sounds including said widely disseminated audio information received thereby into a processing signal;
• code extraction means for extracting the inaudible identification code from said processing signal by detecting said modulations to the energy level thereof within said at least one band of frequencies;
• detector means for determining whether said monitoring device is being carried by a person;
• and
• storage means for storing information from the extracted code indicating the source of said widely disseminated audio information and storing an indication of such determination whether said monitoring device is being carried by a person;
• said transducer means, said code extraction means, said detector means and said storage means being carried within said enclosure.

A personal monitoring device for use in collecting information for estimating an audience for widely disseminated audio information while carried on the person of an individual audience member, the widely disseminated audio information including an inaudible identification code indicating a source thereof, the code produced by modulating a component of a digitized sound signal, comprising:

• an enclosure;
• a microphone within the enclosure and having an output terminal;
• a data processing device w thin the enclosure and having an input coupled to the output terminal of the microphone, the data processing device being programmed to detect the identification code in a signal supplied by the microphone to the input of the data processing device;
• a memory within the enclosure and coupled to the data processing device;
• and
• a motion detector coupled with the data processing device to supply a motion detection signal thereto;
• the data processing device ing programmed to store in the memory the detected identification code and an indication of whether the personal monitoring is being moved by a person based on the motion detection signal .