Print inspection apparatus, print system, print inspection method, and non-transitory recording medium

1 . A print inspection apparatus comprising:

circuitry configured to:

generate a difference image based on a comparison between a read image obtained by reading printed matter printed by a printer and a reference image, and

inspect a defect of the printed matter using the difference image, a plurality of size thresholds, and a plurality of density thresholds corresponding to each of the plurality of size thresholds; and

a memory that stores a plurality of threshold sets each including a combination of the plurality of density thresholds and the plurality of size thresholds,

wherein:

the circuitry is further configured to cause a display to display a setting screen to set the threshold sets, and

the setting screen includes an input field to input the plurality of density thresholds corresponding to each of the plurality of size thresholds.

2 . The print inspection apparatus according to claim 1 , wherein:

the circuitry is further configured to determine a defect of the printed matter using the plurality of density thresholds, and further determine whether the defect having been determined using the plurality of density thresholds is a defect using the plurality of size thresholds.

3 . The print inspection apparatus according to claim 1 , wherein;

the circuitry is further configured to inspect the defect of the printed matter based on a sum of defective pixels determined as defects using the plurality of density thresholds and the plurality of size thresholds.

4 . The print inspection apparatus according to claim 1 , wherein:

the plurality of density thresholds vary depending on the corresponding size thresholds.

5 . The print inspection apparatus according to claim 1 , wherein:

the circuitry is further configured to display, on a display, a user interface screen for selecting one threshold set from the plurality of threshold sets.

6 . The print inspection apparatus according to claim 5 , wherein the circuitry is further configured to:

control printing of a test chart including a plurality of defects,

generate a confirmation image to confirm a defect that is determined using the one threshold set among the plurality of defects, and

display the confirmation image on the user interface screen.

7 . The print inspection apparatus according to claim 6 , wherein;

the test chart includes the plurality of defects arranged in an XY plane, and

the plurality of defects are arranged to have sizes or densities varying in an X direction and a Y direction of the XY plane.

8 . The print inspection apparatus according to claim 1 , wherein the circuitry is further configured to;

receive an input of a density threshold corresponding to one size threshold among the plurality of size thresholds via the setting screen, and

calculate a density threshold corresponding to another size threshold based on the density threshold corresponding to the one size threshold.

9 . The print inspection apparatus according to claim 8 , wherein;

the circuitry is further configured to calculate the density threshold corresponding to said another size threshold using a predetermined function.

10 . The print inspection apparatus according to claim 9 , wherein;

the setting screen includes a selection field to select the predetermined function.

11 . The print inspection apparatus according to claim 1 , wherein:

the circuitry is further configured to calculate a new threshold set based on two existing threshold sets in a case where the threshold sets are set.

12 . The print inspection apparatus according to claim 2 , wherein;

the circuitry determines, as the defect, a dot-shaped defect of the printed matter, and

the plurality of density thresholds and the plurality of size thresholds include a combination of the plurality of density thresholds and the plurality of size thresholds to determine the dot-shaped defect.

13 . The print inspection apparatus according to claim 2 , wherein;

the circuitry determines, as the defect, a linear defect of the printed matter, and

the plurality of density thresholds and the plurality of size thresholds include a combination of the plurality of density thresholds and the plurality of size thresholds to determine the linear defect.

14 . The print inspection apparatus according to claim 13 , wherein;

the linear defect includes a vertical linear defect and a lateral linear defect, and

the plurality of density thresholds and the plurality of size thresholds include a combination of the plurality of density thresholds and the plurality of size thresholds to determine the vertical linear defect, and a combination of the plurality of density thresholds and the plurality of size thresholds to determine the lateral linear defect.

15 . A print inspection apparatus comprising:

circuitry configured to:

generate a difference image based on a comparison between a read image obtained by reading printed matter printed by a printer and a reference image, and

inspect a defect of the printed matter using the difference image, a plurality of size thresholds, and a plurality of density thresholds corresponding to each of the plurality of size thresholds; and

a memory that stores a plurality of threshold sets each including a combination of the plurality of density thresholds and the plurality of size thresholds,

wherein:

the circuitry is further configured to cause a display to display a setting screen to set the threshold sets, and

the circuitry is further configured to:

receive an input of a density threshold corresponding to one size threshold among the plurality of size thresholds via the setting screen, and

calculate a density threshold corresponding to another size threshold based on the density threshold corresponding to the one size threshold.

16 . A print inspection apparatus comprising:

circuitry configured to:

generate a difference image based on a comparison between a read image obtained by reading printed matter printed by a printer and a reference image, and

inspect a defect of the printed matter using the difference image, a plurality of size thresholds, and a plurality of density thresholds corresponding to each of the plurality of size thresholds; and

a memory that stores a plurality of threshold sets each including a combination of the plurality of density thresholds and the plurality of size thresholds,

wherein:

the circuitry is further configured to cause a display to display a setting screen to set the threshold sets, and

the circuitry is further configured to calculate a new threshold set based on two existing threshold sets in a case where the threshold sets are set.

17 . A print inspection apparatus, comprising:

circuitry configured to:

generate a difference image based on a comparison between a read image obtained by reading printed matter printed by a printer and a reference image,

inspect a defect of the printed matter using the difference image, a plurality of size thresholds, and a plurality of density thresholds corresponding to each of the plurality of size thresholds,

determine a defect of the printed matter using the plurality of density thresholds, and further determine whether the defect having been determined using the plurality of density thresholds is a defect using the plurality of size thresholds, and

determine, as the defect, a linear defect of the printed matter,

wherein:

the plurality of density thresholds and the plurality of size thresholds include a combination of the plurality of density thresholds and the plurality of size thresholds to determine the linear defect,

the linear defect includes a vertical linear defect and a lateral linear defect, and

the plurality of density thresholds and the plurality of size thresholds include a combination of the plurality of density thresholds and the plurality of size thresholds to determine the vertical linear defect, and a combination of the plurality of density thresholds and the plurality of size thresholds to determine the lateral linear defect.