Patent · US Expired

Method for determining coordinates of circumscribed rectangular frame of each character for use in optical character reader

US5054091A · kind A · utility

18Cited by
6References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 18, 1990
Grant dateOct 1, 1991
Priority date
Expiry dateApr 18, 2010

Classification

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

Abstract

A method determines coordinates of a circumscribed rectangular frame for enclosing each character based on image data of character images in a recognition area. First of all, specified image data of a predetermined data unit in a transverse direction including at least one bit of black pixel are determined by scanning the image data. Thereafter, top and bottom coordinates of a circumscribed rectangular frame are determined respectively by searching respective image data located at the top and bottom positions among plural image data including at least one bit of black pixel located on the upper and lower sides of the specified image data, wherein respective bits of black pixel of plural image data are substantially continuously connected in a longitudinal direction, and then, leftmost and rightmost coordinates of the circumscribed rectangular frame are determined based on histogram data composed of either logical products or logical sums of respective bits in the transverse direction.

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