05636292 is referenced by 594 patents and cites 160 patents.

An identification code signal is impressed on a carrier to be identified (such as an electronic data signal or a physical medium) in a manner that permits the identification signal later to be discerned and the carrier thereby identified. The method and apparatus are characterized by robustness despite degradation of the encoded carrier, and by permeation of the identification signal throughout the carrier.

Title
Steganography methods employing embedded calibration data
Application Number
8/436098
Publication Number
5636292
Application Date
May 8, 1995
Publication Date
June 3, 1997
Inventor
Geoffrey B Rhoads
West Linn
OR, US
Agent
Klarquist Sparkman Campbell Leigh & Whinston
Assignee
Digimarc Corporation
OR, US
IPC
H04N 1/32
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