Patent · US Expired

Image processing method and apparatus

US6181827A · kind A · utility

3Cited by
3References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 21, 1998
Grant dateJan 30, 2001
Priority date
Expiry dateMay 21, 2018

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N1/4052
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An image processing apparatus comprises an error diffusion processing section 10 for performing error diffusion processing with quantization levels of three or above on image data x(i, j) for producing an output; and a second error diffusion processing section 20 for performing error diffusion processing with quantization levels of three or above on the data outputted from the first error diffusion section 10 for outputting image data y(i, j). Quantization levels of three or above of the quantizer 22 in the error diffusion processing section 20 are determined to be desired value. Quantization levels of three or above of the quantizer 12 in the error diffusion processing section 10 are determined to be levels each between each neighboring two of the quantization levels of the quantizer 22, the minimum level of the image input data x(i, j) and the maximum level of the image input data x(i, j).

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