Patent · US Expired

Image processing apparatus and method and medium

US6389162B2 · kind B2 · utility

31Cited by
20References
30Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 12, 1997
Grant dateMay 14, 2002
Priority date
Expiry dateFeb 12, 2017

Classification

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

Abstract

There are provided an image processing apparatus and method which can properly determine the number of quantization levels for quantizing image data by properly removing noise from the background of the image data. A histogram forming unit forms the output frequency distribution of densities of image data. A background density width detecting unit determines a density area exhibiting output frequency values equal to or larger than a predetermined threshold and including a maximum output frequency value in the formed distribution. A quantization level count determining unit decides the number of quantization levels on the basis of the number of maximum values included in the distribution other than the determined density area.

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