04622583 is referenced by 60 patents and cites 6 patents.

A system which detects the operation of a video tape recorder to obtain data related to the operation of the video tape recorder. The system is also capable of determining the dubbing condition of the video tape recorder over the recording of an ordinary broadcast. The system further determines the receiving channel of the video tape recorder or the television set by directly comparing video signals.

Title
Audience rating measuring system
Application Number
6/682104
Publication Number
4622583
Application Date
December 17, 1984
Publication Date
November 11, 1986
Inventor
Yoshikazu Itoh
Kunitachi
JP
Fumio Watanabe
Zama
JP
Agent
Roberts Spiecens & Cohen
Assignee
Video Research
JP
IPC
H04H 9/00
H04N 17/06
H04N 17/04
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