Image processing apparatus for subjecting a color image to desir

Details Image processing apparatus for subjecting a color image to desir Image processing apparatus for subjecting a color image to desir

1996-10-18

1998-08-25

Frahm, Eric

Facsimile and static presentation processing

Facsimile

Recording apparatus

358298, 358538, 355 77, H04N 123, H04N 140, H04N 146, G03B 2732

Patent

active

057988420

ABSTRACT:
An image processing apparatus includes a K histogram calculating device for calculating a histogram of the density of a color image, after conversion to a monochrome image, and for converting it to a digital signal. Further, the apparatus includes a first reference density level calculating device for calculating a first reference density level corresponding to the density of white regions of the color image; a second reference density level calculating device for calculating a second higher reference density level; a third reference density level calculating device for calculating a third reference density level corresponding to the density of black regions of the color image; and a fourth reference density level calculating device for calculating, based on the second and third reference density levels, a fourth reference density level corresponding to an intermediate density of the color image. A density level conversion value calculating device then calculates, based on the calculated histogram, the ratio of image data having a density level corresponding to the density of black regions of the color image to all image data and calculates, based on the calculated ratio and the third reference density level, a third and a fourth reference density level conversion value. Finally, a gradation conversion executing device converts the gradation of the color image, based on the calculated conversion values and predefined first and second reference density level conversion values.

REFERENCES:
patent: 5309228 (1994-05-01), Nakamura
patent: 5463470 (1995-10-01), Terashita et al.
patent: 5561494 (1996-10-01), Terashita
patent: 5629752 (1997-05-01), Kinjo

Affiliated with

Also associated with

Rating

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

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-39803