Image processing method and apparatus

Details Image processing method and apparatus Image processing method and apparatus

2003-09-22

2008-03-11

Poon, King Y. (Department: 2625)

Facsimile and static presentation processing

Static presentation processing

Attribute control

C358S534000, C358S535000, C358S448000, C382S252000, C382S270000

Reexamination Certificate

active

07342684

ABSTRACT:
It is an object of this invention to prevent a false edge phenomenon in quantization processing for a multilevel image. In order to achieve this object, according to the invention, (1) a reference threshold (Cthreshold) to be used for error diffusion for a cyan (C) component is obtained on the basis of a density value M of a magenta (M) component. (2) A threshold modulation amount table is referred to by using a combination of a density value C of the C component and the density value M of the M component. (3) A correction threshold modulation amount Cthreshold′ is determined by adding the threshold modulation amount obtained in the second step to the reference threshold Cthreshold to be used for error diffusion for the C component. (4) A density Ct after error diffusion for the C component is compared with the correction threshold Cthreshold′. If the density Ct is higher, a quantization value binDataC of the target pixel is set to 255. If the density Ct is lower, the quantization value is set to 0. The same processing as described above is also performed for the cyan component.

REFERENCES:
patent: 4313124 (1982-01-01), Hara
patent: 4345262 (1982-08-01), Shirato et al.
patent: 4459600 (1984-07-01), Sato et al.
patent: 4463359 (1984-07-01), Ayata et al.
patent: 4558333 (1985-12-01), Sugitani et al.
patent: 4608577 (1986-08-01), Hori
patent: 4723129 (1988-02-01), Endo et al.
patent: 4740796 (1988-04-01), Endo et al.
patent: 5201013 (1993-04-01), Kumagai
patent: 5315669 (1994-05-01), Kumagai
patent: 5438634 (1995-08-01), Kumagai
patent: 5949965 (1999-09-01), Gondek
patent: 5973803 (1999-10-01), Cheung et al.
patent: 6169608 (2001-01-01), Yoshida
patent: 6363172 (2002-03-01), Cheung et al.
patent: 2002/0063898 (2002-05-01), Goto et al.
patent: 2003/0067617 (2003-04-01), Kato et al.
patent: 2 352 353 (2001-01-01), None
patent: 54-56847 (1979-05-01), None
patent: 59-123670 (1984-07-01), None
patent: 59-138461 (1984-08-01), None
patent: 60-71260 (1985-04-01), None
patent: 8-279920 (1996-10-01), None
patent: 8-307669 (1996-11-01), None
patent: 8-307680 (1996-11-01), None
patent: 9-139841 (1997-05-01), None
patent: 2729278 (1997-12-01), None
patent: 11-10918 (1999-01-01), None
patent: 2000-354172 (2000-12-01), None
patent: 2002-171407 (2002-06-01), None
Robert W. Floyd and Louis Steinberg, “An Adaptive Algorithm for Spatial Greyscale,” Proceeding of the SID, vol. 17/2 Second Quarter, 75-77 (1976).

Affiliated with

Also associated with

Rating

Image processing method and apparatus 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, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Image processing method and apparatus will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3976303