Patent · US Expired

Detecting line segments and predetermined patterns in an optically scanned document

US5129012A · kind A · utility

27Cited by
6References
37Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 21, 1990
Grant dateJul 7, 1992
Priority date
Expiry dateMar 21, 2010

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06V30/10
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

Line segments in stored picture data derived from an optically scanned document are detected by detecting line elements in the picture data, determining if the length of a line element is greater than a threshold length l.sub.th, determining a connecting relationship of one line element of greater than threshold length to another line element of greater than threshold length, and identifying a line segment in accordance with the connecting relationship of the line elements. Predetermined patterns formed of the detected line segments are detected by sensing if two line segments adjoin each other, determining the adjoining relationship of those two line segments, and identifying the pattern which includes those two line segments as a function of their adjoining relationship.

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