Patent · US Expired

Image processing apparatus and method

US6333788A · kind A · utility

35Cited by
3References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 27, 1997
Grant dateDec 25, 2001
Priority date
Expiry dateFeb 27, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06V30/10
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

The luminance frequencies are calculated in units of blocks in a multi-valued image, and the binarization threshold values in units of blocks are calculated on the basis of the calculated luminance frequencies. By interpolating the binarization threshold values in units of blocks, the binarization threshold values in units of pixels are calculated, and the multi-valued image is binarized using the binarization threshold values in units of pixels.

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