Image processing apparatus, image processing method, and medium that obtains a difference in color information at corresponding positions between a composite image and a print image

1. An image processing apparatus comprising:

one or more memories storing instructions and one or more processors that execute the instructions:

to obtain a plurality of print images obtained by reading each of a plurality of print products;

to evaluate a difference between the plurality of print images;

to set an exclusion region in inspection of a print product based on a result of the evaluation; and

to obtain a difference in color information at corresponding positions between a composite image of the plurality of print images and one of the plurality of print images as a feature amount indicating the magnitude of the difference.

2. The image processing apparatus according to claim 1 , wherein each of the plurality of print products includes a common object, and

the one or more processors further execute the instructions to evaluate a difference between respective portions of the plurality of print images,

wherein the respective positions of the portions relative to the object are the same.

3. The image processing apparatus according to claim 1 , wherein each of the print products includes a common object, and

the one or more processors further execute the instructions to align the plurality of print images to each other based on the object, and to evaluate a difference between the plurality of aligned print images.

4. The image processing apparatus according to claim 3 , wherein the one or more processors further execute the instructions to evaluate a local difference between the plurality of print images at each position.

5. The image processing apparatus according to claim 4 , wherein the one or more processors further execute the instructions to set a region in which the difference is greater than a predetermined criterion as the exclusion region.

6. The image processing apparatus according to claim 5 , wherein each of the plurality of print products is obtained by printing the object on a medium on which an image having been printed in advance.

7. The image processing apparatus according to claim 1 , wherein the one or more processors further execute the instructions to set a region where the difference is greater than a predetermined criterion as the exclusion region.

8. The image processing apparatus according to claim 1 , wherein the one or more processors further execute the instructions to evaluate a difference in color information at corresponding positions between the plurality of print images in order to evaluate the difference.

9. The image processing apparatus according to claim 1 , wherein the one or more processors further execute the instructions to obtain distribution of color information at corresponding positions between the plurality of print images as a feature amount indicating the magnitude of the difference.

10. The image processing apparatus according to claim 1 , wherein the one or more processors further execute the instructions to evaluate blurring at each position of a composite image of the plurality of print images in order to evaluate the difference.

11. The image processing apparatus according to claim 1 , wherein the one or more processors further execute the instructions to obtain a difference in edge amounts at corresponding positions between a composite image of the plurality of print images and one of the plurality of print images as a feature amount indicating the magnitude of the difference.

12. The image processing apparatus according to claim 1 , wherein the one or more processors further execute the instructions to obtain a difference in pixel value histograms at corresponding positions between a composite image of the plurality of print images and one of the plurality of print images as a feature amount indicating a magnitude of the difference.

13. The image processing apparatus according to claim 1 , wherein the one or more processors further execute the instructions to display the set exclusion region on a display.

14. The image processing apparatus according to claim 1 , wherein the one or more processors further execute the instructions to inspect an inspection target print product such that inspection on the exclusion region is avoided.

15. The image processing apparatus according to claim 14 , wherein the one or more processors further execute the instructions to inspect the print product based on a comparison of portions at corresponding positions in an image, obtained by reading the inspection target print product, and a reference image indicating an allowable print result.

16. The image processing apparatus according to claim 15 , wherein the one or more processors further execute the instructions to obtain an image obtained by reading the inspection target print product as at least one print image among the plurality of print images.

17. An image processing method comprising:

obtaining a plurality of print images obtained by reading each of a plurality of print products;

evaluating a difference between the plurality of print images;

setting an exclusion region in inspection of a print product based on a result of the evaluation; and

obtaining a difference in color information at corresponding positions between a composite image of the plurality of print images and one of the plurality of print images as a feature amount indicating the magnitude of the difference.

18. A non-transitory computer-readable medium storing a program executable by a computer to perform a method comprising:

obtaining a plurality of print images obtained by reading each of a plurality of print products;

evaluating a difference between the plurality of print images;

setting an exclusion region in inspection of a print product based on a result of the evaluation; and

obtaining a difference in color information at corresponding positions between a composite image of the plurality of print images and one of the plurality of print images as a feature amount indicating the magnitude of the difference.