Image analysis – Image transformation or preprocessing
Patent
1996-01-17
1998-10-20
Lee, Thomas D.
Image analysis
Image transformation or preprocessing
382272, 382270, G06K 940, G06K 938
Patent
active
058259406
ABSTRACT:
An object of the present invention is to provide an image processing apparatus capable of, at high speed, forming a half tone image exhibiting excellent linearity and gradation expressing characteristics while requiring only a simple structure. The image processing apparatus including a mean density calculating circuit for calculating a mean density in a predetermined region, a random number generator for generating random number data, an adder for adding, at a ratio corresponding to a level of input multivalue image data, the mean density obtained by said mean density calculating circuit and the random number data supplied from the random number generator, and a comparator for binary-coding the multivalue image data in such a manner that a value obtained by said adder is used as a threshold. To prevent roughness appearing in a highlight region in a binary-coded output image and obtain a satisfactory half tone output image exhibiting excellent gradation expressing characteristics, the mean density calculating circuit has a changing unit for changing the mean density.
REFERENCES:
patent: 4562486 (1985-12-01), Suzuki et al.
patent: 4876610 (1989-10-01), Ohsawa et al.
patent: 4878125 (1989-10-01), Katayama et al.
patent: 4958236 (1990-09-01), Nagashima et al.
patent: 4958238 (1990-09-01), Katayama et al.
patent: 4975786 (1990-12-01), Katayama et al.
patent: 5008950 (1991-04-01), Katayama et al.
patent: 5086484 (1992-02-01), Katayama et al.
patent: 5121446 (1992-06-01), Yamada et al.
patent: 5121447 (1992-06-01), Tanioka et al.
patent: 5130819 (1992-07-01), Ohta
patent: 5153925 (1992-10-01), Tanioka et al.
patent: 5157741 (1992-10-01), Katayama
patent: 5436736 (1995-07-01), Shono
patent: 5577136 (1996-11-01), Tanioka et al.
Floyd, et al., "An Adaptive Algorithm for Spatial Gray Scale", SID 75 Digest, pp. 36-37.
Tanioka Hiroshi
Yamagata Shigeo
Canon Kabushiki Kaisha
Grant II Jerome
Lee Thomas D.
LandOfFree
Image processing method and apparatus for binary-coding multival does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Image processing method and apparatus for binary-coding multival, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Image processing method and apparatus for binary-coding multival will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-254487