Image inspection apparatus
US8498489B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 16, 2009 |
| Grant date | Jul 30, 2013 |
| Priority date | — |
| Expiry date | Nov 23, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/30148
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The present invention provides a unified template matching technique which allows an adequate matching position to be provided even in an image with a distorted pattern shape and a variation in edge intensity. A correlation value contribution rate map is created for the vicinity of each of top candidate positions obtained by applying a centroid distance filter to a normalized correlation map resulting from template matching. A corrected intensity image is created from the correlation value contribution rate maps. Luminance correction is performed based on the corrected intensity image. Local matching is performed again on the vicinity of each candidate position. The candidates are then re-sorted based on candidate positions and correlation values newly obtained. Thus, even in an image with a distorted pattern shape and a variation in edge intensity, an adequate matching position can be provided in a unified manner.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.