Patent · US Expired

System, circuit, and method for edge detection in a binary optical code

US7201322B2 · kind B2 · utility

7Cited by
12References
37Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 10, 2004
Grant dateApr 10, 2007
Priority date
Expiry dateJun 10, 2024

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06V10/28
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

Systems better detect transitions in a binary optical code signal and thus better detect edges in binary optical codes, such as bar codes. The optical code signal imperfectly indicates perceived regions of relatively dark and light areas arranged in an alternating pattern as part of an optical code. That signal is differentiated to form a first derivative. Due to various non-ideal conditions, the first derivative may have a series of successive local peaks of the same polarity. Peaks in the series having a peak value less than a previous peak value in the series are ignored, thereby resulting in a set of unignored peaks. From the unignored peaks in the series is chosen the one peak occurring last in order. According to the chosen peak, there is generated a signal more reliably indicating the true edge position between light and dark areas in the pattern.

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