Method for determining orientation of contour line segment in local area and for determining straight line and corner
US5586199A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 2, 1993 |
| Grant date | Dec 17, 1996 |
| Priority date | — |
| Expiry date | Jun 2, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06V10/48
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The present invention relates to a method for determining an orientation of a line segment in a contour in a local area of a binary contour image. The number of pixels having a predetermined value and located in each orientation in the local area, is obtained, and it is determined that a line segment exists in an orientation in which the number of pixels is large. Further, when it is determined that the number of pixels located in each of a plurality of orientations and having a predetermined value is greater than a sum of the numbers of pixels in orientations adjacent to said each orientation on both sides thereof, it is determined that a line segment exists in said each orientation. Two orientations in which large numbers of pixels are located are detected, and it is determined whether the point is a constituent of a line segment, a line segment of the sub-straight-line form, or a near-corner point, depending on angles made by the two orientations is equal to 180.degree., or a difference of the angles made by the two orientations from 180.degree.. Contiguously arrayed pixels in the same orientation are detected as a line segment. A position and an orientation are obtained from po…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.