Method and apparatus for decoding bar code symbols using ratio analysis of module size
US5767497A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 4, 1996 |
| Grant date | Jun 16, 1998 |
| Priority date | — |
| Expiry date | Dec 4, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K7/14
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for decoding bar code symbols using an analysis of the ratios of the module size for the bars and spaces of the bar code. The invention is applicable to any bar code having one or more nominal widths in the bars and spaces, and is particularly useful in bar codes having multiples widths in the specification for the bar code and in situations where the bar code signal has a low signal-to-noise ratio, or is degraded because of a damaged, smudged, or dirty bar code, or where the bar code is read at less than the optimum angle. The invention identifies mis-decoded characters and uses adaptive techniques to decode characters previously non-decodable or mis-decoded by standard methods, thereby improving the decode rate as compared to prior techniques. The decoding rate is improved without having to re-scan the bar code for a new signal, thereby making the invention particularly useful for high-speed or one-pass decoding operations.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.