Patent · US Expired

Video signature comparator and method

US4907080A · kind A · utility

8Cited by
3References
12Claims
0Family size

Inventors

Key dates

Filing dateMay 30, 1989
Grant dateMar 6, 1990
Priority date
Expiry dateMay 30, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06V40/30
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

A relatively low cost, easy to operate video signature comparator and a corresponding method by which a known signature is visually compared to a sample signature to determine whether both signatures were made by the same individual. The signator comparator has particular application to forgery detection or to applications for verifying the authenticity of a signature. An electronic circuit is disclosed which displays video signals that are representative of the known and sample signatures. The circuit enhances video image density variations through extreme contrast and brightness adjustment and forces the lighter regions of each signature to white, such that only the dark stroke lines (indicative of those regions having the greatest density where the maker applied the most pressure) are displayed on video monitor. By visually comparing the characteristic density/pressure variations of the known signature to the sample, an observer can more accurately determine whether both signatures originated from the same maker.

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