Patent · US Expired

Method and apparatus for decoding bar code symbols along search steps

US5478999A · kind A · utility

80Cited by
16References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 27, 1994
Grant dateDec 26, 1995
Priority date
Expiry dateMay 27, 2014

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06K7/1491
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A system for detecting a bar code symbol receives a two-dimensional image containing the symbol, where the system has no a priori knowledge of the orientation of the symbol in the image. The system scans the image in one dimension to locate a quiet zone for the symbol and searches the image in one dimension to identify a start/stop character of the symbol. A system for decoding a bar code symbol having a plurality of elements receives a signal representative of the symbol. The system searches the signal along a first search step to characterize the width of one of the elements. The system then selects a second search step by projecting from the first search step onto a reference line, where the reference line is not parallel to either the first or second search steps. The system then searches the signal along the second search step to characterize the width of another of the elements. A system for decoding a bar code symbol having at least three elements receives a signal representative of the symbol. The system characterizes a first set of two or more elements by searching the signal along a first search step. The system also characterizes a second set of two or more elements by s…

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