Patent · US Expired

Image processor

US6538771B1 · kind B1 · utility

18Cited by
13References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 20, 1998
Grant dateMar 25, 2003
Priority date
Expiry dateJan 20, 2018

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N1/4105
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

In an image processor, multi-level image data are divided into blocks, and compressed in the unit of block. The compressed multi-level image data of a block are converted to compressed bi-level image data without expanding the multi-level image data. For example, the compressed multi-level image data on an image of uniform density are converted to compressed bi-level image data expressed with area gradation. In another image processor, the compressed multi-level image data of a block are converted to compressed multi-level image data, without expanding the multi-level image data. For example, the compressed multi-level image data on an image of bi-level image expressed with area gradation are converted to compressed multi-level image data of a half-tone image.

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