System and method for inferring vessel speed from overhead images
US8437509B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 16, 2011 |
| Grant date | May 7, 2013 |
| Priority date | — |
| Expiry date | Jan 9, 2032 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06V20/13
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Systems and methods for determining the speed of a vessel from an overhead image of the vessel's wake can include the initial step of defining a cusp line for the wake. A representative line segment from the defined cusp line that is suitable for building an image intensity profile for the image can be selected. Once the intensity profile is built along the line segment, the wake wavelength λcusp from the image intensity profile can be found by measuring the distance between successive points of intensity maxima (or successive intensity minima points) along the line segment. Once λcusp is found, the vessel speed can be determined from the images according to the formula νship=√{square root over (1.352*λcusp)}. The systems and methods can be practiced using any overhead imagery systems that display a vessel's wake, including synthetic aperture radar (SAR) and electro-optical (EO) overhead imagery systems.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.