Correlation peak finding method for image correlation displacement sensing
US7885480B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 31, 2006 |
| Grant date | Feb 8, 2011 |
| Priority date | — |
| Expiry date | Oct 13, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T7/32
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A correlation function peak finding method for an image correlation displacement sensing system is provided. The method may include capturing a reference image and a displaced image, and searching for an initial peak correlation function value point (CFVP) with pixel-level resolution based on correlating the reference image and displaced images at a plurality of offset positions. Then a complete set of CFVPs may be determined at each offset position in an analysis region surrounding the initial peak CFVP. Then a preliminary correlation function peak location is estimated with sub-pixel resolution, based on CFVPs included in the analysis region. Finally, curve-fitting operations are performed to estimate a final correlation function peak location with sub-pixel accuracy, wherein the curve-fitting operations apply a windowing function and/or a set of weighting factors that is/are located with sub-pixel resolution based on the preliminary sub-pixel correlation function peak location.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.