Title:
画像処理装置およびその方法
Document Type and Number:
Japanese Patent JP4011933
Kind Code:
B2
Abstract:
Upon outputting halftone image data to an output device, density transformation is prevalently performed to improve image quality. Density transformation corresponds to linear gamma correction, and cannot correct for color fog and the like that may occur in a photo image. Hence, lightness and color-difference information of halftone image data is acquired on the basis of low-frequency components of frequency data obtained by transforming halftone image data into spatial frequency components, and a lightness and color-difference transform amount of the halftone image data is set on the basis of the acquired lightness and color-difference information.
Inventors:
Akiki Yamada
Masao Kato
Fumitaka Goto
Kentaro Yano
Masao Kato
Fumitaka Goto
Kentaro Yano
Application Number:
JP2002046688A
Publication Date:
November 21, 2007
Filing Date:
February 22, 2002
Export Citation:
Assignee:
Canon Inc
International Classes:
G06T5/00; H04N1/60; H04N1/46
Domestic Patent References:
| JP11346372A | ||||
| JP10023261A | ||||
| JP10191074A |
Attorney, Agent or Firm:
Yasunori Otsuka
Shiro Takayanagi
Yasuhiro Otsuka
Shuji Kimura
Shiro Takayanagi
Yasuhiro Otsuka
Shuji Kimura