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:
Sep. 03, 2002
Filed:
Jan. 21, 1999
Masaki Kishimoto, Kanagawa, JP;
Sony Corporation, Tokyo, JP;
Abstract
An image processing method and an image processing apparatus are provided for maintaining image quality through simple processing while reducing the number of gradation levels of image data by error diffusion processing. In an image processing apparatus, data outputted from a filter is subtracted from input image data x(i, j) at a first subtracter. Data outputted from the subtracter is quantified at a quantifier. 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 quantization error converter, quantization error e (i, j) is converted into quantization error e (i, j) within a specific range determined for each quantization level, based on the quantization level after quantization at the quantizer. Quantization error e (i, j) is inputted to the filter. Data outputted from the filter is inputted to the first subtracter.