Misalignment detecting apparatus, misalignment detecting method, and computer program product

Abstract

A correction-coefficient calculating unit calculates a correction coefficient to correct misalignment between a first print image and a second print image. A correcting unit corrects the first print image based on the correction coefficient to obtain a corrected first image. A pixel-value determining unit assigns a pixel value based on pixel-value matching state at corresponding positions in the corrected first image and the second print image. An image generating unit generates a misalignment display image from the corrected first image and the second print image that is assigned a predetermined pixel value. An output unit that outputs the misalignment display image.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic of an image processing system according to a first embodiment of the present invention;

FIG. 2 is a functional block diagram of an image processing apparatus shown in FIG. 1;

FIG. 3 is an example of contents of a pixel-value determination table;

FIG. 4 is a flowchart of image processing performed by the image processing system shown in FIG. 1;

FIG. 5 is a detailed flowchart of a misalignment display process shown in FIG. 4;

FIG. 6 is a schematic for explaining the process of correcting a first print image shown in FIG. 5;

FIG. 7 is a schematic for explaining the process of generating a misalignment display image shown in FIG. 5;

FIG. 8 is an example of a misalignment display image;

FIG. 9 is a schematic of a hardware configuration of the image processing apparatus;

FIG. 10 is a functional block diagram of an image processing apparatus according to a second embodiment of the present invention;

FIG. 11 is an example of screen display of correction values output from a misalignment amount output unit shown in FIG. 10;

FIG. 12 is a flowchart of image processing according to the second embodiment;

FIG. 13 is a functional block diagram of an image processing apparatus according to a third embodiment of the present invention;

FIG. 14 is a detailed flowchart of a misalignment display process according to the third embodiment;

FIG. 15 is a schematic for explaining the process of thickening a line in a corrected first image shown in FIG. 14;

FIG. 16 is a schematic for explaining the process of generating a misalignment display image shown in FIG. 14;

FIG. 17 is an example of a misalignment display image;

FIG. 18 is a functional block diagram of an image processing apparatus according to a fourth embodiment of the present invention;

FIG. 19 is a detailed flowchart of a misalignment display process according to the fourth embodiment;

FIGS. 20A and 20B are schematics for explaining the process of calculating a difference degree according to a modification example;

FIG. 21 is an example of screen display on a display shown in FIG. 1;

FIG. 22 is a schematic of an image processing system according to a fifth embodiment of the present invention;

FIG. 23 is a functional block diagram of a Multifunction Product (MFP) shown in FIG. 22;

FIG. 24 is a flowchart of image processing performed by the image processing system shown in FIG. 22;

FIG. 25 is a detailed flowchart of a print-position adjusting process shown in FIG. 24;

FIG. 26 is a schematic of an image processing system according to a sixth embodiment of the present invention;

FIG. 27 is a functional block diagram of an image processing apparatus shown in FIG. 26;

FIG. 28 is a functional block diagram of an image processing apparatus in an image processing system according to a seventh embodiment of the present invention;

FIG. 29 is an example of a setting screen;

FIG. 30 is a flowchart of a misalignment display process according to the seventh embodiment;

FIG. 31 is a schematic for explaining area setting;

FIG. 32 is a schematic of a first print image after image correction, a second print image, and a misalignment display image generated therefrom;

FIG. 33 is schematic of a first area;

FIG. 34 is a schematic of a first print image after area correction, a second print image, and a misalignment display image generated therefrom;

FIG. 35 is a functional block diagram of an image processing apparatus in an image processing system according to an eighth embodiment of the present invention;

FIG. 36 is an example of a setting screen; and

FIG. 37 is a flowchart of a misalignment display process according to the eighth embodiment.

Claims

1. A misalignment detecting apparatus that detects misalignment of a second image with respect to a first image, the misalignment detecting apparatus comprising: a digitizing unit that digitizes images to obtain the first image and the second image;an image generating unit that generates a third image indicating misalignment between the first image and the second image in a preset mode based on misalignment between corresponding points on the first image and the second image; andan output unit that visually outputs the third image.

2. The misalignment detecting apparatus according to claim 1, wherein the image generating unit assigns a different pixel value to a first portion where a pixel in the first image and a corresponding pixel in the second image match and a second portion where a pixel in the first image and a corresponding pixel in the second image do not match.

3. The misalignment detecting apparatus according to claim 2, wherein the image generating unit assigns a pixel value representing a color that is easier to visually recognize to the first portion compared to the second portion.

4. The misalignment detecting apparatus according to claim 2, wherein the image generating unit assigns a different pixel value to a portion where a black image area in the first image and a white image area in the second image overlap and a portion where a white image area in the first image and a black image area in the second image overlap.

5. The misalignment detecting apparatus according to claim 1, further comprising a line-width changing unit that increases a width of a line in any one of the first image and the second image, wherein the image generating unit generates the third image based on the first image and the second image, in one of which the width of the line has been changed.

6. The misalignment detecting apparatus according to claim 1, further comprising: a coefficient calculating unit that calculates a correction coefficient based on the misalignment between the corresponding points on the first image and the second image; anda correcting unit that corrects the first image based on the correction coefficient to obtain corrected first image, whereinthe image generating unit generates the third image in a preset mode based on misalignment between the corresponding points on the corrected first image and the second image.

7. The misalignment detecting apparatus according to claim 1, further comprising a difference calculating unit that calculates a degree of difference between the first image and the second image, wherein the output unit outputs the third image when the degree of difference exceeds a predetermined threshold.

8. The misalignment detecting apparatus according to claim 7, wherein the difference calculating unit calculates the degree of difference based on a shape of an image included in the first image and the second image.

9. The misalignment detecting apparatus according to claim 1, wherein the digitizing unit digitizes a first print obtained by printing data on a print medium held by a first medium holding unit to obtain the first image, and a second print obtained by printing data on a print medium held by a second medium holding unit to obtain the second image, andthe image generating unit generates the third image based on the first image and the second image.

10. The misalignment detecting apparatus according to claim 1, further comprising: an area-correction-coefficient calculating unit that calculates, based on misalignment between corresponding points in a first area of the first image and a second area of the second image that corresponds to the first area, an area correction coefficient between the first area and the second area; andan area correcting unit that corrects the first area based on the area correction coefficient to obtain corrected first area, whereinthe image generating unit generates the third image in a preset mode based on misalignment between the corresponding points in the corrected first area and the second area.

11. The misalignment detecting apparatus according to claim 10, wherein the first area is a rectangle in a predetermined size.

12. The misalignment detecting apparatus according to claim 10, wherein the first area includes a sequence of black pixels.

13. The misalignment detecting apparatus according to claim 10, wherein the first area is a rectangle circumscribing the sequence of black pixels.

14. The misalignment detecting apparatus according to claim 10, further comprising an instruction receiving unit that receives an instruction for area correction, wherein the area-correction-coefficient calculating unit calculates the area correction coefficient when the instruction receiving unit receives the instruction.

15. The misalignment detecting apparatus according to claim 1, further comprising: an image-correction-coefficient calculating unit that calculates an image correction coefficient between the first image and the second image based on the misalignment between the corresponding points on the first image and the second image;an image correcting unit that corrects the first image based on the image correction coefficient to obtain corrected first image;an area-correction-coefficient calculating unit that calculates, based on misalignment between corresponding points in a first area of the first image and a second area of the second image that corresponds to the first area, an area correction coefficient between the first area and the second area when a degree of difference between the corrected first image and the second image is equal to or less than a predetermined threshold; andan area correcting unit that corrects the first area based on the area correction coefficient to obtain corrected first area, whereinthe image generating unit generates the third image in a preset mode based on misalignment between the corresponding points in the corrected first area and the second area.

16. A misalignment detecting method for detecting misalignment of a second image with respect to a first image, the misalignment detecting method comprising: digitizing images to obtain the first image and the second image;generating a third image indicating misalignment between the first image and the second image in a preset mode based on misalignment between corresponding points on the first image and the second image; andoutputting visually the third image.

17. The misalignment detecting method according to claim 16, further comprising assigning a different pixel value to a portion where a pixel in the first image and a corresponding pixel in the second image match and a portion where a pixel in the first image and a corresponding pixel in the second image do not match.

18. The misalignment detecting method according to claim 16, further comprising: calculating a correction coefficient based on the misalignment between the corresponding points on the first image and the second image; andcorrecting the first image based on the correction coefficient to obtain corrected first image, whereinthe generating includes generating the third image in a preset mode based on misalignment between the corresponding points on the corrected first image and the second image.

19. The misalignment detecting method according to claim 16, further comprising calculating a degree of difference between the first image and the second image, wherein the outputting includes outputting the third image when the degree of difference exceeds a predetermined threshold.

20. A computer program product for detecting misalignment of a second image with respect to a first image, the computer program product comprising a computer usable medium having computer readable program codes embodied in the medium that when executed causes a computer to execute: digitizing images to obtain the first image and the second image;generating a third image indicating misalignment between the first image and the second image in a preset mode based on misalignment between corresponding points on the first image and the second image; andvisually outputting the third image.