Method and apparatus for locating and decoding machine-readable symbols
US5786583A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 16, 1996 |
| Grant date | Jul 28, 1998 |
| Priority date | — |
| Expiry date | Feb 16, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06V10/245
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for locating and decoding machine-readable symbols is provided. The present invention stores an image of the symbol and locates all Jordan curves having an angular length less than .pi. within the image of the symbol. The present invention finds and selects all convex Jordan curves from the set of all Jordan curves found within the stored image. The present invention determines equations of a pair of tangent lines from end points of each convex Jordan curve and determines an equation of a center line for each pair of tangent lines. The present invention determines a point of intersection of the center lines, and based on the point of intersection, locates a center point of a finder pattern of the symbol. The present invention confirms that the located center point is indeed the center of the finder pattern, and thereafter decodes the symbol.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.