Patent · US Expired

Digital watermarking security systems

US7502937B2 · kind B2 · utility

20Cited by
74References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 4, 2003
Grant dateMar 10, 2009
Priority date
Expiry dateFeb 11, 2026

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N2201/327
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A variety of systems responsive to watermarked documents are detailed. In one, watermarking is employed to facilitate system access. In another, security is provided through analyzing digitally watermarked documents. In yet another, a digital watermark-based combination lock is adapted to analyze a sequence (and perhaps an orientation) of presented digitally watermarked cards.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.