Method and apparatus for measuring angular rotation of an object
US6711304B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 26, 2001 |
| Grant date | Mar 23, 2004 |
| Priority date | — |
| Expiry date | Dec 23, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/30148
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A system is disclosed for determining the rotational orientation of an object. An image of the object is digitally captured. The digital image is filtered through an edge detection operation to enhance the edge information contained in the image. The filtered image is rotated through a series of incremental angles to produce a series of rotated images. Each rotated image is projected onto an x-axis and y-axis defined by pixel grid axes defined by the original image. The projection of the rotated images produces projected pixel counts formed by the summation of pixel value differences of the x-axis and y-axis on the projected image. For each rotated image, a score corresponding to the sum of the difference of gray-scale values for adjacent projected pixels is computed. The scores for the projections of each rotated image are plotted on a score-angle graph. A curve which includes the highest score and the neighboring next highest scores is interpolated to determine the peak score. The peak score corresponds to the scene angle of the object relative to the x-axis and y-axis defined by the original image.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.