Method and apparatus for sub-pixel edge detection
US6917721B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 16, 2001 |
| Grant date | Jul 12, 2005 |
| Priority date | — |
| Expiry date | May 7, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T7/13
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for processing an image are disclosed. For edge detection, the zero crossing pixel location, n0, within the image is identified. Then, a sub-pixel position offset, a, is determined. The offset is a relationship between interpolated image and an interpolated kernel at the zero crossing pixel location. Finally, the interpolated position for the edge location, t0, is determined from the pixel location, n0, and the sub-pixel position offset, a. For matching the detected edges of an object to edges of a model object, translation [v1, v2] between a detected edge of an object in the image and the corresponding edge of a model object is first determined. Next, cross correlation between the detected edge and the corresponding model edge is calculated. Then, translation error [e1, e2] is determined. Finally, the translation is updated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.