Patent · US Expired

Image data processing through changing error diffusing technique depending upon kind of images

US6118905A · kind A · utility

7Cited by
8References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 19, 1996
Grant dateSep 12, 2000
Priority date
Expiry dateJan 19, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG09G2320/0613
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An image processing apparatus detects, in step 1, whether or not differences between currently supplied image data and image data of a previous pixel are more than a predetermined value m, and identifies a border of a computer-created image or a natural image, where a brightness level differs from the remaining area of the image, when the differences are more than the predetermined value m. Conversely, when the differences are less than the predetermined value m, the image processing apparatus checks, in step 2, whether image data at a pixel before and a pixel two before the current pixel are identical with respect to the color components constituting the color image. When the differences are not all zero, it is checked whether or not the image data at a pixel before the current pixel and the image data at the current pixel are all zero. When the image data are not identical, the color image is identified as being a natural image. When the image data are identical, the color image is identified as being a computer-created image. In step 3, the computer-created image is checked as to whether it is a 2-pixel checkered image.

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