Patent · US Expired

Image processing device for processing grey level images

US5625717A · kind A · utility

54Cited by
13References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 22, 1993
Grant dateApr 29, 1997
Priority date
Expiry dateJun 22, 2013

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06V10/28
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

An image processing device includes: a DOG filtering means for applying a DOG filter upon the grey level image of an object; and a tri-level thresholding means for thresholding the output of the DOG filtering means at two distinct threshold levels, thereby obtaining a tri-level image of the object. The 0-level regions of the tri-level image correspond to regions of the original image, such as the surface areas of the object, within which the variation of the grey level is small. The boundary between two 0-regions is marked by adjacent parallel strips of a (+)-region and a (-)-region, wherein the zero-crossing line between the (+)-region and the (-)-region clearly defines the contour line of the 0-regions. This method of tri-level quantization provides a basis for efficient template matching of the images of objects, recognition or identification of objects, the detection of movement vectors of objects, and the detection of the parallax of a continuously moving objects.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.