Fast location of address blocks on gray-scale images
US6343139B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 12, 1999 |
| Grant date | Jan 29, 2002 |
| Priority date | — |
| Expiry date | Mar 12, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S707/99933
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method for locating a structured field in a gray-scale image of an object, including choosing a plurality of anchor points in the image, each anchor point having a gray-scale value associated therewith. For each anchor point there is determined a horizontal variation dependent on a difference between the gray-scale value of the anchor point and the gray-scale value of a horizontally neighboring anchor point, and there is also determined a vertical variation dependent on a difference between the gray-scale value of the anchor point and the gray-scale value of a vertically neighboring anchor point. Those anchor points whose vertical and horizontal variations obey a first or a second predefined condition are defined as vertically or horizontally dominant respectively. One or more kernels are defined in the image, each such kernel comprising a group of anchor points n predetermined mutual proximity and satisfying a third predefined condition relating the number of vertically-dominant and horizontally-dominant anchor points in the group. The structured field in the image is located using one or more kernels.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.