04697209 is referenced by 511 patents and cites 6 patents.

A method and apparatus for identifying programs such as television programs received from various sources detects the occurrence of predetermined events such as scene changes in a video signal and extracts a signature from the video signal. The signatures and the times of occurrence of the signatures are stored and subsequently compared with reference signatures to identify the program. The signatures may be compared in pairs to increase resolution, and the time interval between events or signatures may also be used to identify the program, either by themselves or in conjunction with the signatures.

Title
Methods and apparatus for automatically identifying programs viewed or recorded
Application Number
6/604367
Publication Number
4697209
Application Date
April 26, 1984
Publication Date
September 29, 1987
Inventor
Daozheng Lu
Dunedin
FL, US
David A Kiewit
Palm Harbor
FL, US
Agent
Mason Kolehmainen Rathburn & Wyss
Assignee
A C Nielsen Company
IL, US
IPC
H04N 17/06
H04N 17/04
H04H 9/00
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