Apparatus, system, and method of inspecting image, and computer-readable medium storing image inspection control program

1. An information processing apparatus, comprising:

a read image obtainer implemented by circuitry and configured to obtain a scanned determination image including a plurality of different dot patterns output by an image forming apparatus on a recording medium, the determination image being an image output by the image forming apparatus to determine output characteristics of the image forming apparatus; and

a setting value calculator implemented by the circuitry and configured to

for each of the different dot patterns of the obtained scanned determination image,

determine densities of different colors of the respective dot pattern, and

determine a total number of pixels influencing the density of each coefficient of a dot gain correction filter, with respect to each target pixel, and

calculate the coefficients of the dot gain correction filter based on the determined densities of the different colors of the different dot patterns and the total number of pixels, determined for each coefficient of the dot gain correction filter and for each of the different dot patterns.

2. The information processing apparatus according to claim 1 , wherein

the dot gain correction filter includes coefficients a-d,

the coefficient a is applied a central pixel to be corrected,

the coefficient b defines the influence of a pixel that is vertically-adjacent to the central pixel,

the coefficient c defines the influence of a pixel that is horizontally-adjacent to the central pixel, and

the coefficient d defines the influence of a pixel that is diagonally-adjacent to the central pixel.

3. The information processing apparatus according to claim 2 , wherein

the coefficient b defines the influence of each pixel that is vertically-adjacent to the central pixel,

the coefficient c defines the influence of each pixel that is horizontally-adjacent to the central pixel, and

the coefficient d defines the influence of each pixel that is diagonally-adjacent to the central pixel.

4. The information processing apparatus according to claim 1 , wherein the information processing apparatus is configured to inspect a scanned image obtained by scanning an image output on a recording medium, and further comprises:

an inspection reference image generator implemented by the circuitry and configured to generate an inspection reference image to inspect the scanned image based on image data of the image output on the recording medium; and

an inspection result acquisition unit implemented by the circuitry and configured to acquire a result of a defect determination of the scanned image based on a comparison between the inspection reference image and the scanned image, wherein

the inspection reference image generator corrects the density of the image data to be processed in generating the inspection reference image based on the coefficients.

5. The information processing apparatus according to claim 1 , wherein the setting value calculator is configured to calculate the coefficients which are used to perform density correction of image data to be processed when an inspection reference image is generated, and

calculates values indicating the output characteristics of each pixel and pixels surrounding the respective pixel as the coefficients based on (1) a calculation result calculated by adding up an influence on density by the output characteristics of each pixel and the pixels surrounding the respective pixels for each of the different dot patterns, and (2) a relationship between the determination image and a density of each of the different dot patterns extracted from the scanned determination image.

6. A method of an information processing apparatus for dot gain correction, the method comprising:

obtaining a scanned determination image including a plurality of different dot patterns output by an image forming apparatus on a recording medium, the determination image being an image output by the image forming apparatus to determine output characteristics of the image forming apparatus; and

for each of the different dot patterns of the obtained scanned determination image,

determining densities of different colors of the respective dot pattern, and

determining a total number of pixels influencing the density of each coefficient of a dot gain correction filter, with respect to each target pixel; and

calculating, by circuitry of the information processing apparatus, the coefficients of the dot gain correction filter based on the determined densities of the different colors of the different dot patterns and the total number of pixels, determined for each coefficient of the dot gain correction filter and for each of the different dot patterns.

7. A non-transitory computer-readable storage medium storing instructions which when executed by a computer cause to computer to perform a method of dot gain correction, the method comprising:

obtaining a scanned determination image including a plurality of different dot patterns output by an image forming apparatus on a recording medium, the determination image being an image output by the image forming apparatus to determine output characteristics of the image forming apparatus; and

for each of the different dot patterns of the obtained scanned determination image,

determining densities of different colors of the respective dot pattern, and

determining a total number of pixels influencing the density of each coefficient of a dot gain correction filter, with respect to each target pixel; and

calculating, by the computer, the coefficients of the dot gain correction filter based on the determined densities of the different colors of the different dot patterns and the total number of pixels, determined for each coefficient of the dot gain correction filter and for each of the different dot patterns.