Patent · US Expired

Image processing method and apparatus

US5768441A · kind A · utility

17Cited by
2References
34Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 2, 1995
Grant dateJun 16, 1998
Priority date
Expiry dateNov 2, 2015

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06T2207/20021
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

An image processing method and an image processing apparatus for determining the best digitizing threshold value, thereby enabling best-case digitizing across the entire input image, even when determination of a subject image within an image block is mistaken. The input image is separated into plural blocks; a temporary digitization threshold value is calculated for each of the separated blocks; the presence of text characters or other predetermined subject images is evaluated in each of the separated blocks; and block information for each of the separated blocks, including the temporary digitization threshold value, subject presence information, and the final digitization threshold value of each block for which said threshold value has been determined, is referenced to determine the final digitization threshold value for each block. Each block is then digitized using these best-case threshold values to achieve consistent, best-case digitization across the entire input image.

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