Patent · US Active

Image processing apparatus and method for executing a process of error diffusion

US7855809B2 · kind B2 · utility

18Cited by
26References
8Claims
0Family size

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Inventors

Key dates

Filing dateDec 3, 2003
Grant dateDec 21, 2010
Priority date
Expiry dateFeb 15, 2027

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N1/52
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An image processing apparatus executes an error diffusion process to multivalue image data consisting of a plurality of density components. A first processor executes the error diffusion process by changing at least one of a quantization threshold value and a quantization diffusion coefficient which are used for the error diffusion process based on a value of the multivalue image data of the density components or a value calculated from the multivalue image data value. A second processor executes the error diffusion process by setting the quantization threshold value and the quantization diffusion coefficient which are used for the error diffusion process into fixed values. An error diffusion processing controller controls to execute the error diffusion process to at least one color among the density components by the first processor and execute the error diffusion process to other density components by the second processor.

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