Automated inspection of objects undergoing general affine transformation
US6421458B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 28, 1998 |
| Grant date | Jul 16, 2002 |
| Priority date | — |
| Expiry date | Oct 1, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/30108
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
During statistical training and automated inspection of objects by a machine vision system, a General Affine Transform is advantageously employed to improve system performance. During statistical training, the affine poses of a plurality of training images are determined with respect to an alignment model image. Following filtering to remove high frequency content, the training images and their corresponding affine poses are applied to an affine transformation. The resulting transformed images are accumulated to compute template and threshold images to be used for run-time inspection. During run-time inspection, the affine pose of the run-time image relative to the alignment model image is determined. Following filtering of the run-time image, the run-time image is affine transformed by its affine pose. The resulting transform image is compared with the template and threshold images computed during statistical training to determine object status. In this manner, automated training and inspection is relatively less demanding on system storage, and results in an improvement in system speed and accuracy.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.