Patent · US Expired

Apparatus and method for characterizing, encoding, storing, and searching images by shape

US6678411B1 · kind B1 · utility

7Cited by
15References
23Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 27, 2000
Grant dateJan 13, 2004
Priority date
Expiry dateMar 27, 2020

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06V10/92
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

An optical image characterizer 10 detects light energy as discrete angular orientations of a slit in a rotating spatial filter positioned at the focal plane of a Fourier transform lens, where a Fourier transform pattern of spatial frequencies of an image are formed. Detection of light energy with a small array (e.g., 16×16) photodetector is enhanced by splitting the beam containing the filtered light energy pattern and projecting it onto two photodetector arrays in offset, virtual juxtaposed relation to each other. Detected light intensities I at discrete angular orientations R are stored in RIXel data arrays with or without searchable flags X, such as distortion factors.

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