US Patent No. 9,444,973

IMAGE PROCESSING FOR PERFORMING A TRAPPING PROCESS OF INCREASING A DENSITY OF A PIXEL


Patent No. 9,444,973
Issue Date September 13, 2016
Title Image Processing For Performing A Trapping Process Of Increasing A Density Of A Pixel
Inventorship Kenichirou Haruta, Yokohama (JP)
Assignee CANON KABUSHIKI KAISHA, Tokyo (JP)

Claim of US Patent No. 9,444,973

1. An image processing apparatus for performing a trapping process of increasing a density value of a pixel, comprising:
an inputting unit configured to input image data including a target pixel and a peripheral pixel of the target pixel, the
target pixel having a density value of a first color component and a density value of a second color component and the peripheral
pixel having a density value of the first color component and a density value of the second color component;

a trapping unit configured to increase, on a basis of at least the density value of the first color component and the density
value of the second color component of the target pixel and the density value of the first color component and the density
value of the second color component of the peripheral pixel, the density value of the second color component of the target
pixel; and

a printing unit configured to print the target pixel by using at least the increased density value of the second color component
of the target pixel,

wherein the trapping unit is configured to calculate a first trap rate by using the density value of the first color component
of the target pixel, a second trap rate by using the density value of the second color component of the target pixel, a third
trap rate by using the density value of the first color component of the peripheral pixel, and a fourth trap rate by using
the density value of the second color component of the peripheral pixel,

wherein the trapping unit is configured to calculate a final trap rate by using the first trap rate, the second trap rate,
the third trap rate, and the fourth trap rate,

wherein the trapping unit is configured to calculate a trap color density value by using the density value of the second color
component of the peripheral pixel and the final trap rate, and

wherein the trapping unit is configured to increase the density value of the second color component of the target pixel to
the trap color density value.