Fiducial marker based on blocks of different grayscales
US11107243B2 · kind B2 · utility
Inventors
Key dates
| Filing date | Jan 21, 2020 |
| Grant date | Aug 31, 2021 |
| Priority date | — |
| Expiry date | Jan 21, 2040 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/10024
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The present invention discloses fiducial marker systems or tag systems and methods to detect and decode a tag. The tag comprises a plurality of cells arranged in a grid pattern. The plurality of cells forms a square or rectangular shape. Each cell is in square or rectangular shape and has either black, white, or gray grayscale. Any two cells that share a common borderline should have different grayscales; and the four corner cells of the tag are all in black. The method for detecting and decoding such a tag comprises detecting a plurality of connected cells in an image, determining whether the plurality of connected cells in the image have all three grayscales, determining whether total number of cells in the plurality of connected cells is greater than a predetermined threshold, determining whether any two cells in the plurality of connected cells that share a common borderline in the image have different grayscales, and decoding the tag based on the grayscales of the plurality of connected cells in the image.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.