The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 21, 2003
Filed:
Feb. 23, 1999
Masaki Kishimoto, Kanagawa, JP;
Sony Corporation, Tokyo, JP;
Abstract
An image processing method and an image processing apparatus are provided to maintain image quality through simple processing while reducing the number of gradation levels of image data by error diffusion process. In an image processing apparatus, data outputted from a filter is subtracted from input image data x(i, j) at the subtracter. Data outputted from the subtracter is quantized at a quantizer. Data outputted from the quantizer is outputted as output image data y(i, j). Furthermore, the data outputted from the subtracter is subtracted from the data outputted from the quantizer at a second subtracter to produce quantization error e(i, j). At a filter section, filtering process is performed on the quantization error e(i, j). Data outputted from the filter section is inputted to the first subtracter. According to the gradation values of the input image data x(i, j), weight coefficient selecting section selects a filter coefficient, which corresponds to weight coefficient for error diffusion at the filter section, and sets it up in the filter section.