System and method for two-dimensional keystone correction for aerial imaging
US7379619B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 9, 2005 |
| Grant date | May 27, 2008 |
| Priority date | — |
| Expiry date | Nov 24, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/30236
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A digital keystone correction process locates image points in a corrected image from image points in a distorted image that was produced by misalignment of the axis of a sensor such as a camera. The correction process locates corrected image points by constructing intercept points that are the intersections of the extended sides of a quadrilateral in the distorted image plane that is constructed from a known rectangular feature in the subject plane. Reference points are located by drawing a line through each intercept point and the distorted image point. Distances are found from the intercept points to the image points and the reference points. The distances are scaled and corrected with an offset to locate the coordinates of the image points in the corrected image plane. This process can correct alignment errors of pitch, yaw, and roll between the subject plane and an image plane such as photographic film.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.