Patent · US Expired

Two-dimensional code reading apparatus

US6000614A · kind A · utility

135Cited by
11References
55Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 22, 1997
Grant dateDec 14, 1999
Priority date
Expiry dateDec 22, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06K7/14
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A two-dimensional code reading apparatus uses the image of a reference pattern of a known shape in the two-dimensional code to compute areas, shapes and positions of cells in the image of the two-dimensional code and corrects these computed values using correction values obtained by identifying cells isolated from cells of the same type in at least one direction whenever they appear and extracting their actual boundary coordinates directly from the image data. As a result, even if there is distortion in the image of the two-dimensional a reading scope for each cell to be read is set to a suitable area and the reading position of each cell is determined accurately in correspondence with the distortion and the content of the two-dimensional code is thereby read correctly.

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