Method and apparatus for locating patterns in an optical image
US5717785A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 9, 1994 |
| Grant date | Feb 10, 1998 |
| Priority date | — |
| Expiry date | May 9, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/30148
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The invention provides methods and apparatus for processing an image to identify the position of a linear pattern--for example, a line or a cross-hair comprising a plurality of intersecting lines. The system performs a first processing step for generating a projection of the image along axes aligned with an expected position of the linear patterns. A second processing step performs a mirror symmetry filtering on the projection to bring out a single peak corresponding to the center of the linear pattern. To further isolate that peak, the system performs a further filtering operation to remove peaks of lesser slope angle, so that only a highly sloped spike corresponding to the linear pattern will remain. The position of the center that peak corresponds to the center of the linear pattern in the original input signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.