Image processing device, image processing method, and program

Abstract

To appropriately perform inspection of print position deviation even when the width of a print media is larger than a width at which the print medium can be read.SOLUTION: An image processing apparatus according to the present invention has: setting means that sets a condition for detecting deviation of a printing position on a print medium in a printed material; and inspection means that inspects the deviation of a printing position based on the condition from data obtained by reading the print medium. When the width of the print medium is larger than a width at which the print medium can be read, the condition has a small settable range compared with a case where the width of the print medium is smaller than a width at which the print medium can be read.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to image processing for inspecting printed matter. [Background technology]

[0002] In the inspection after print output, when the image reading device acquires the image data of the inspection target, a part of the paper of the printed matter may exceed the maximum reading width of the image reading device, resulting in an unreadable paper area. In such a case, the unreadable paper area is estimated, so an error occurs due to the estimation process when comparing the reference image data, which is a good product, with the image data of the inspection target, which may result in a false detection of a print defect.

[0003] Patent Document 1 discloses a method of performing inspection while excluding protruding parts from the inspection target by setting the protruding parts as non-inspection areas. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2004-310726 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, while the method disclosed in Patent Document 1 makes it possible to change the inspection settings for the overflowing portion, it does not change the inspection settings for the entire paper surface as in the case of print misalignment, and therefore it is not possible to properly inspect for print misalignment in the case of overflowing. [Means for solving the problem]

[0006] In order to solve the above problem, an image processing device according to the present invention has a setting means for setting conditions for detecting a misalignment of a print position in a printed matter, and an inspection means for inspecting the printed matter based on an inspection target image obtained by reading the printed matter and the conditions, The conditions are set within a range determined by upper and lower limits, The range in which the conditions can be set when the width of the printed matter is larger than the readable width of the print medium is greater than the range in which the conditions can be set when the width of the printed matter is smaller than the readable width. , the upper limit is equal and the lower limit is larger It is characterized by: Effect of the Invention

[0007] Even when the width of the print medium is greater than the width at which the print medium can be read, it is possible to appropriately check for print position misalignment. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing the overall configuration of a printing system including an image processing apparatus. [Diagram 2] FIG. 1 is a block diagram showing a configuration of an image processing device. [Diagram 3] 11 is a flowchart showing the flow of an inspection process. [Figure 4] 5 is a flowchart of an inspection parameter setting range control process in the first embodiment. [Diagram 5] FIG. 4 is a diagram showing an example of an examination setting screen in the first embodiment. [Figure 6] FIG. 4 is a diagram showing an example of an examination setting screen in the first embodiment. [Figure 7] FIG. 4 is a diagram showing an example of an examination setting screen in the first embodiment. [Figure 8] FIG. 11 is a graph showing the relationship between the inspection level and the amount of print position deviation. [Figure 9] 13 is a flowchart of an inspection parameter setting range control process in the second embodiment. [Figure 10] FIG. 11 is a diagram showing an example of an examination setting screen in the second embodiment. [Figure 11] 5 is a diagram showing the relationship between the maximum image reading width and the width of a sheet of paper. [Figure 12]11A and 11B are diagrams showing examples of an inspection target image and a reference image when the paper does not exceed the maximum reading width of the image reading device. [Figure 13] FIG. 13 is a diagram showing a state after the reference image and the inspection target image have been aligned. [Figure 14] 11A and 11B are diagrams showing examples of an inspection target image and a reference image when a sheet of paper exceeds the maximum reading width of an image reading device. [Figure 15] FIG. 11 is a block diagram showing a detailed configuration of an inspection parameter setting range control unit in the third embodiment. [Figure 16] 13 is a flowchart of an inspection parameter setting range control process in the third embodiment. [Figure 17] FIG. 4 is a diagram for explaining a maximum conveying position deviation amount. [Figure 18] 13 is a diagram showing an example of an inspection setting screen for setting parameters corresponding to vertical and horizontal print position misalignment independently. FIG. [Figure 19] FIG. 4 is a diagram for explaining skew of paper. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the following embodiment does not limit the present invention, and not all of the combinations of features described in the present embodiment are necessarily essential to the solution of the present invention. Note that the same configurations are described with the same reference numerals, and duplicated descriptions are omitted. Also, each process (step) in the flow chart is indicated by a reference numeral beginning with S. EXAMPLES

[0010] In the first embodiment, a process for appropriately inspecting the print position shift even when the print medium size (e.g., paper size) exceeds the maximum reading width of the image reading device will be described. Specifically, a process for changing the settable range of the inspection parameters for the print position shift inspection that can be set according to the minimum detectable position shift amount will be described.

[0011] 1 shows an example of the overall configuration of a printing system that outputs and inspects printed matter, including an image processing device 100 in this embodiment. The printing system in this embodiment has the image processing device 100, a printing server 180, and a printing device 190. Note that in this embodiment, the image processing device 100 and the printing device 190 are described as separate entities, but the image processing device 100 may be provided within the printing device 190.

[0012] The printing server 180 has a function of generating a print job for a document to be printed, and inputting the print job to the printing device 190 .

[0013] The printing device 190 forms an image on a print medium (on printing paper) based on a print job input from the printing server 180. The printing device 190 can be an offset printing device, an electrophotographic device, an inkjet device, or the like. In this embodiment, the printing device 190 is an electrophotographic printing device. The printing device 190 has a paper feed unit 191, and the user sets printing paper in the paper feed unit 191 in advance. When a print job is input, the printing device 190 transports the printing paper set in the paper feed unit 191 along a transport path 192, forms an image on one or both sides of the paper, and sends it to the image processing device 100.

[0014] The image processing device 100 performs an inspection process to check for the presence or absence of printing defects on the paper, i.e., the printed matter, on which the printing device 190 forms an image and which is sent through a conveying path 192. That is, the image processing device 100 functions as an inspection processing device. The image processing device 100 has a CPU 101, a RAM 102, a ROM 103, a main memory device 104, an image reading device 105, an interface (I / F) 106 with the printing device, a general-purpose interface (I / F) 107, a user interface (UI) panel 108, and a main bus 109 inside. The image processing device 100 may also be composed of a plurality of processing devices connected via a network, for example. Furthermore, the image processing device 100 has a conveying path 110 for printed matter connected to the conveying path 192 of the printing device 190, an output tray 111 for printed matter that has passed the inspection, and an output tray 112 for printed matter that has failed the inspection due to the discovery of a printing defect. The classification of printed matter may be configured to be more detailed than just the two types, pass and fail.

[0015] The CPU 101 is a processor that comprehensively controls each unit in the image processing device 100. The RAM 102 functions as a main memory, a work area, etc. for the CPU 101. The ROM 103 stores a group of programs executed by the CPU 101. The main storage device 104 stores applications executed by the CPU 101, data used in image processing, etc.

[0016] An image reading device (scanner) 105 can read one or both sides of a printed matter sent from a printing device on a conveying path 110 and acquire it as image data. A printing device I / F 106 is connected to a printing device 190, and can synchronize the timing of processing printed matter with the printing device 190 and can communicate each other's operating status. A general-purpose I / F 107 is a serial bus interface such as USB or IEEE1394, and allows a user to take out data such as logs and import some data into the image processing device 100.

[0017] The UI panel 108 is, for example, a liquid crystal display, and functions as a user interface for the image processing device 100, displaying the current status and settings and informing the user. Also, by providing a touch panel or buttons, it accepts instructions from the user. A main bus 109 connects the various parts of the image processing device 100. In addition, although not shown in FIG. 1, various parts inside the image processing device 100 and the printing system can be operated by instructions from the CPU 101. For example, it is possible to synchronously move the transport paths, and to switch whether printed matter is sent to the pass output tray 111 or the fail output tray 112 depending on the inspection results. Also, a GPU may be provided in addition to the CPU.

[0018] Overall, the image processing device 100 performs an inspection process, described below, based on the image data of the printed matter read by the image reading device 105 while conveying the printed matter sent from the printing device 190 along the conveying path 110. If the result of the inspection process shows that the printed matter passes the inspection, it is conveyed to an output tray 111 indicating that it has passed, and if not, it is conveyed to an output tray 112 indicating that it has failed. In this way, only those whose quality has been confirmed can be collected in the output tray 111 as deliverables for delivery.

[0019] 2 shows the configuration of each processing block of the image processing device 100 related to the inspection process. The image processing device 100 has an inspection image acquisition unit 201, a reference image acquisition unit 202, an inspection parameter setting range control unit 203, an inspection setting unit 204, an inspection processing unit 205, and a result output unit 206.

[0020] The inspection image acquisition unit 201 reads the printed matter from the printing device 190 on the conveying path 110 by the image reading device 105, and acquires it as inspection target image data (hereinafter, also referred to as inspection image data or inspection target data). The acquired image data is stored in the RAM 102 or the main memory device 104.

[0021] The reference image acquisition unit 202 acquires reference image data (also called reference image data) generated in advance by reading it from the main storage device 104 to the RAM 102. Alternatively, the reference image acquisition unit 202 may acquire the reference image data as image data of the printed matter on the transmission path 110 in synchronization with the output of the printed matter from the printing device 190.

[0022] The inspection parameter setting range control unit 203 controls the settable inspection parameters for print position misalignment based on the maximum reading width of the image reading device 105 and the paper size of the printing paper, and reflects this in the display on the UI panel 108. The inspection setting unit 204 performs various settings related to the inspection based on instructions from the user acquired via the UI panel 108. The inspection processing unit 205 performs the inspection by comparing the inspection image data with the reference image data. The result output unit 206 displays the inspection results on the UI panel 108, and switches between sending the printed matter to the output tray 111 for pass or the output tray 112 for fail.

[0023] Next, a detailed configuration of the inspection parameter setting range control unit 203 will be described. The inspection parameter setting range control unit 203 has a maximum reading width acquisition unit 2031, a paper size acquisition unit 2032, a minimum detectable positional deviation determination unit 2033, a size determination unit 2034, and an inspection parameter setting range change unit 2035.

[0024] A maximum read width acquisition unit 2031 acquires the maximum read width of the image reading device 105. A paper size acquisition unit 2032 acquires the width and height of the paper as the paper size of the print paper. Hereinafter, the paper size may refer to only the width of the paper. A minimum detectable positional deviation determination unit 2033 determines the minimum detectable positional deviation based on the maximum read width and the paper size. A size determination unit compares the maximum read width with the paper size to determine whether the paper size exceeds the maximum read width of the image reading device 105. An inspection parameter setting range change unit 2035 changes the settable inspection parameters for print position deviation based on the above size determination result, and reflects this in the display of the UI panel 108.

[0025] FIG. 3 is a flowchart of the inspection process performed by the image processing device 100 of this embodiment.

[0026] In S301, the inspection parameter setting range control unit 203 performs control processing of settable print position deviation inspection parameters based on the maximum reading width of the image reading device 105 and the paper size of the printing paper. The details of the processing will be described later.

[0027] In S302, the reference image acquisition unit 202 acquires reference image data by reading reference image data, which has been generated in advance by reading a printed matter that is free of printing defects such as misalignment, from the main storage device 104 to the RAM 102. Alternatively, the reference image data may be acquired as image data of a printed matter on the feed path 110 in synchronization with the output of the printed matter from the printing device 190, and used as the reference image data. However, it is necessary to confirm that the printed matter is free of printing defects such as misalignment.

[0028] In S303, the inspection setting unit 204 performs inspection setting based on an instruction from the user acquired via the UI panel 108. Each setting value is stored in the RAM 102 or the main storage device 104. In this embodiment, the print position deviation inspection parameter, which is a threshold value for detecting the print position deviation, is set as the inspection setting. However, for example, the setting of the inspection parameter corresponding to the print defect such as a stain may be additionally performed. FIGS. 5, 6, and 7 show examples of the inspection setting screen in the UI panel. In the example shown in FIG. 5, the user sets the inspection parameter of the print position deviation by inputting a numerical value in the edit box 501. In the example shown in FIG. 6, the user sets the inspection parameter of the print position deviation by selecting a desired setting value from the pull-down menu 601 and the pull-down menu 602. Also, in the example shown in FIG. 7, the user sets the inspection parameter of the print position deviation by selecting a desired setting level from the pull-down menu 701. For each level, the print position deviation amount as shown in FIG. 8 is set in advance.

[0029] In S304, the inspection image acquisition unit 201 reads the printed matter printed by the printing device 190 with the image reading device 105 and acquires it as inspection target image data. The acquired inspection target image data is stored in the RAM 102 or the main storage device 104. FIG. 12(a) shows an example of an inspection target image when the paper does not exceed the maximum reading width of the image reading device 105. This is acquired by reading a printed matter on which print data 1203 is printed on a paper 1202 with the image reading device 105. In this example, backing areas 1201 exist above, below, left and right of the area showing the paper 1202 in the inspection target image. This is an area that is generated when the reading target does not exist in the sensor unit of the image reading device 105 during reading. Next, as shown in FIG. 11, when the width Wp of the paper 1101 exceeds the maximum reading width Ws of the image reading device 105, the inspection target image becomes an image as shown in FIG. 14(a). In other words, the image becomes an image in which a part of the paper that protrudes beyond the maximum reading width of the image reading device 105 is missing. 12(a), this example shows an image obtained by scanning a printed matter in which print data 1403 is printed on paper 1402, and backing areas 1401 exist above and below the area showing paper 1402. Protruding areas 1404 show areas of the paper that could not be scanned by image scanning device 105, and are areas that do not exist in the actual image to be inspected.

[0030] In S305, the inspection processing unit 205 performs an inspection for the presence or absence of a printing defect by comparing the reference image data with the image data to be inspected. In this embodiment, the inspection is performed for printing position deviation as a printing defect. First, feature points for alignment are extracted from the reference image. For example, when corner information of an image is used as a feature point, corner detection is performed using a known algorithm such as Harris corner detection, and multiple feature points are extracted, for example, in descending order of feature amount. Alternatively, feature points may be manually added and adjusted. In this embodiment, since affine transformation is used for alignment processing, three or more feature points need to be extracted. In addition, due to the nature of affine transformation, it is preferable that the feature points are far apart from each other and are not arranged in a straight line. Note that the feature point extraction process may be performed in advance when the reference image data is acquired and stored in the RAM 102 or the main storage device 104, and the feature points may be read out and used.

[0031] Fig. 12(b) shows an example of feature points 1205 extracted from a reference image when the paper does not exceed the maximum reading width of the image reading device 105. Fig. 14(b) shows an example of feature points 1405 extracted from a reference image when the paper protrudes beyond the maximum reading width of the image reading device 105.

[0032] Next, a search is made for corresponding points in the inspection target image that correspond to these feature points. For this, a corresponding point search algorithm such as a known template matching can be used. Then, affine parameters for performing affine transformation are calculated from the relationship between the coordinates of multiple feature points in the reference image and the coordinates of corresponding points in the inspection target image that correspond to these feature points. Then, the reference image and the inspection target image are aligned by affine transformation using these affine parameters.

[0033] If the paper extends beyond the maximum reading width of the image reading device 105, the corners of the paper are not visible on the image being inspected, so these coordinates are estimated values. In this embodiment, the coordinates of the invisible corners of the paper are estimated as follows. First, it is assumed that both ends of the paper in the width direction extend evenly beyond the image reading device 105, as shown in FIG. 14(a). Then, W is calculated from the center of the edges along the top and bottom edges of the paper in the image in both left and right directions. p We assume that the corner of the paper is located at a distance of W / 2. p is the width of the paper. In this case, if the paper width is in inches and the coordinates on the image to be inspected are in pixels, the reading resolution (ppi) of the image reading device 105 can be used to convert the physical paper size into the coordinates on the image to be inspected.

[0034] 13 shows the state after the alignment of the reference image 1301 and the inspection target image 1302. The positions of the print data 1204 on the reference image and the print data 1203 on the inspection target image match, but the positions of the paper corners of each image are misaligned. The difference in the coordinates of this paper corner is the print position misalignment. If the paper extends beyond the maximum reading width of the image reading device 105, the corners of the paper on the inspection target image are estimated values, so the coordinates after alignment also contain an error.

[0035] If the amount of print misalignment falls within this error range, the print misalignment cannot be evaluated correctly. Therefore, in S301, it is necessary to control the print misalignment inspection parameters that can be set by taking this error into account.

[0036] In this embodiment, the horizontal print position misalignment 1303 and the vertical print position misalignment 1304 are calculated independently as the print position misalignment. Finally, the calculated print position misalignment is compared with the inspection parameters for the print position misalignment set in S303, and if the value is greater than the set threshold, it is determined that there is a print defect, and the inspection result is stored in the RAM 102 or the main memory device 104.

[0037] In S306, the result output unit 206 reads out the inspection results from the RAM 102 or the main storage device 104, and displays the inspection results on the UI panel 108. Also, depending on the inspection results, the unit switches between sending the printed matter to the output tray 111 for acceptable prints or the output tray 112 for unacceptable prints.

[0038] In S307, it is determined whether or not to end the inspection. If the inspection of all print data has been completed, or if an instruction to end the inspection has been received from the user, the inspection process ends. If not, the process returns to S304 and continues.

[0039] <Inspection parameter setting range control process> Here, the inspection parameter setting range control process in S301 will be described in detail.

[0040] 4 is a flowchart showing the flow of the inspection parameter setting range control process in this embodiment. Each step of the flowchart will be described below.

[0041] In S401, the maximum reading width acquisition unit 2031 acquires the maximum reading width W s For example, if the image reader 105 is a line scanner, the effective sensor width is acquired as the maximum reading width.

[0042] In S402, the paper size acquisition unit 2032 acquires the width of the paper as the size of the print paper. For example, the paper size specified by the user via the UI panel 108, the paper size set as a default value, or the paper size set at the time of printing is used. In this embodiment, the width of the paper is the length of the side of the paper that is perpendicular to the paper transport direction. FIG. 11 shows the maximum read width W s , paper width W p , and the paper transport direction.

[0043] In S403, the size determination unit 2034 determines the paper size based on the width W of the paper acquired in S402. pand the maximum read width W obtained by S401 s If the paper width W p If it is greater, the process proceeds to S404; if not, the process ends.

[0044] In S404, the minimum detectable positional deviation amount determination unit 2033 calculates the minimum detectable positional deviation amount. s and the paper width W p Based on this, the minimum positional deviation D that can be detected using formula (1) is min Request.

[0045]

number

[0046] In S405, the inspection parameter setting range change unit 2035 sets the minimum positional deviation amount D min Based on this, the range of inspection parameters that can be set by the user is changed. FIG. 5 shows an example of an inspection setting screen on the UI panel. FIG. 5(a) shows the default inspection setting screen. If the paper width does not exceed the maximum reading width, the user sets the inspection threshold for print position misalignment by inputting it into edit box 501 within the inspection parameter setting range 502 shown here, i.e., within the range of "1.0 mm to 10.0 mm." In contrast, FIG. 5(b) shows the state of the inspection setting screen on the UI panel after the change in the range of inspection parameters that can be set is executed in this step. Here, the minimum amount of position misalignment that can be inspected calculated in S404 is D min In FIG. 5(a), the inspection parameter setting range 502 is "1.0 mm-10.0 mm", whereas in FIG. 5(b), the inspection parameter setting range 502 is changed to be narrowed to "3.0 mm-10.0 mm". In this way, the minimum value of the settable inspection parameter is D min Changes will be made so that the above is true.

[0047] Through the series of processes described above, when the paper size exceeds the maximum reading width of the image reading device 105, the setting range of the inspection parameters for the print position deviation inspection that can be set according to the minimum amount of position deviation that can be inspected is changed to be smaller. This makes it possible to appropriately inspect the print position deviation even when the paper size exceeds the maximum reading width of the image reading device 105.

[0048] In this embodiment, an example of inputting data into an edit box is shown as an example of a UI panel for setting the inspection threshold for print misalignment, but the UI is not limited to this. For example, as shown in FIG. 6, the inspection threshold for print misalignment may be set by selecting a desired value from a drop-down list. FIG. 6(a) shows a default inspection setting screen. When the width of the paper does not exceed the maximum reading width, the inspection threshold for print misalignment is set by selecting one of five parameters from a drop-down list 601 shown here, i.e., 1.0, 2.0, 3.0, 4.0, and 5.0. FIG. 6(b) shows the state of the inspection setting screen in the UI panel after the range of the settable inspection parameters is changed in S405. Here, the minimum amount of inspection misalignment calculated in S404 is D min In Fig. 6(a), the five types of parameters are shown as selection candidates, whereas in Fig. 6(b), the number of selection candidates is the same as in Fig. 6(a), but the contents are different from Fig. 6(a). The minimum selectable parameter value is D min The selection candidates have been changed as described above.

[0049] As another example, FIG. 7 shows a UI panel for setting the inspection threshold for print misalignment by selecting a desired inspection level from a drop-down list 701. A print misalignment threshold is associated with each of these inspection levels in advance, an example of which is shown in FIG. 8. FIG. 8(a) is a correspondence table between the inspection level and the print misalignment threshold used when the paper width does not exceed the maximum reading width. In contrast, FIG. 8(b) shows a correspondence table between the inspection level and the print misalignment threshold after the range of the settable inspection parameters is changed in S405. When the print misalignment threshold corresponding to the minimum level is D min In this manner, the correspondence table between each level and the threshold value of the print position deviation is changed. EXAMPLES

[0050] In the first embodiment, an example was described in which the setting range of the inspection parameters is controlled by restricting the input range of the inspection parameters and the selectable magnitude of print misalignment to be smaller. In this embodiment, an example of modification is described in which the number of selectable inspection levels is restricted to be smaller according to the minimum amount of misalignment that can be inspected.

[0051] In this embodiment, in the flow of the inspection process performed by the image processing device 100 described in the embodiment 1 with reference to Fig. 3, only the inspection parameter setting range control process shown in S301 is different from the embodiment 1, so the details of this process will be described. The other processes are the same as those in the embodiment 1, so the description will be omitted.

[0052] <Inspection parameter setting range control process> FIG. 9 is a flowchart showing the flow of the inspection parameter setting range control process in this embodiment.

[0053] In S901, the inspection parameter setting range change unit 2035 changes the inspection-possible minimum positional deviation amount D minBased on the above, the range of the inspection level that the user can set is changed. FIG. 10 shows an example of an inspection setting screen in the UI panel of this embodiment. In this example, the desired inspection level is selected from a drop-down list to set the inspection threshold for print misalignment. FIG. 10(a) shows a default inspection setting screen. If the width of the paper does not exceed the maximum reading width, the inspection threshold for print misalignment is set by selecting one of five parameters from a drop-down list 1001 shown here, that is, from level 1 to level 5. Note that the inspection threshold for print misalignment corresponding to each level is assumed to be linked and stored in advance, as shown in FIG. 10(c). For example, if the user selects level 1, 1.0 mm is set internally as the inspection threshold for print misalignment. FIG. 10(b) shows the state of the inspection setting screen in the UI panel after the range of the inspection level that can be set is changed in this step. Here, the minimum amount of misalignment that can be inspected calculated in S404 is set to D min In FIG. 10(a), the five levels mentioned above are shown as the selection candidates for the inspection level, whereas in FIG. 10(b), the selection candidates for the parameter are limited to three levels, from level 3 to level 5. From the correspondence table shown in FIG. 10(c), it can be seen that the threshold value for the print position deviation is D min The minimum level that is equal to or greater than the level is obtained, and the contents of the drop-down list 1002 are changed so that this becomes the minimum level that can be selected in the drop-down list 1002. In this example, min = 3.0, level 3 is obtained from the correspondence table, and the minimum level that can be selected in the drop-down list 1002 is changed to this level 3.

[0054] By the above-described process, when the paper size exceeds the maximum reading width of the image reading device, the number of selectable inspection levels is reduced according to the minimum amount of misalignment that can be inspected. This makes it possible to appropriately inspect for print misalignment. EXAMPLES

[0055] In this embodiment, a process will be described in which the minimum detectable amount of positional deviation is determined further taking into consideration the positional deviation during transport, and the inspection parameter setting range is controlled based on this.

[0056] FIG. 15 shows the configuration of each processing block of the image processing device 100 related to the inspection processing in this embodiment. The configuration is such that a conveying position deviation amount acquisition unit 1501 is added to the configuration described in FIG. 2 of the first embodiment. The paper on which the print data is printed is sent to the image reading device 105 through a conveying path formed of conveying rollers and the like. At that time, a deviation may occur in the conveying position due to mechanical errors during paper feeding. The maximum value of such conveying position deviation amount can be calculated in advance by estimating the above-mentioned mechanical errors and the like, and stored in the main memory device 104 or the like. The conveying position deviation amount acquisition unit 1501 acquires this known maximum conveying position deviation amount by reading it from the main memory device 104 to the RAM 102. Note that the other processing blocks are the same as those in FIG. 2, so their explanations will be omitted.

[0057] In this embodiment, in the flow of the inspection process performed by the image processing device 100 described in the embodiment 1 with reference to Fig. 3, only the inspection parameter setting range control process shown in S301 is different from the embodiment 1, so the details of this process will be described. The other processes are the same as those in the embodiment 1, so the description will be omitted.

[0058] <Inspection parameter setting range control process> FIG. 16 is a flowchart showing the flow of the inspection parameter setting range control process in this embodiment.

[0059] In S1601, the transport position deviation amount acquisition unit 1501 acquires the known maximum transport position deviation amount ε by reading it from the main storage device 104 to the RAM 102. Fig. 17 is a diagram for explaining the maximum transport position deviation amount ε. Paper 1701 shows the case where the paper passes through the center of the image reading device 105 without any transport position deviation. 1702 shows the paper when the maximum transport position deviation occurs to the left. Also, 1703 shows the paper when the maximum transport position deviation occurs to the right. As shown in this figure, the difference in the paper width direction between 1701 and 1702, or between 1701 and 1703, is the maximum transport position deviation amount ε.

[0060] In S1602, the conveying position deviation amount acquisition unit 1501 further determines whether the maximum conveying position deviation amount ε is (W p -W s ) / 2 or less. s is the maximum read width, W p If this condition is met, the process proceeds to S1603, and if not, the process proceeds to S1604.

[0061] In S1603, the detectable minimum positional deviation amount determining unit 2033 determines the detectable minimum positional deviation amount D min Set as =ε.

[0062] In S1604, the detectable minimum positional deviation amount determining unit 2033 determines the detectable minimum positional deviation amount D min =(W p -W s ) / 2.

[0063] By using the processing described above, the minimum detectable amount of positional deviation is determined taking into account the positional deviation during transport, and the range in which the inspection parameters can be set is controlled based on this, making it possible to perform appropriate inspection even if the paper size exceeds the maximum reading width.

[0064] In this embodiment, an example of controlling the settable range of the inspection parameters has been described as in the first embodiment, but the following method may also be used. That is, a process is performed to limit the number of selectable inspection levels to a smaller value as shown in the second embodiment based on the minimum detectable positional deviation amount determined in consideration of the positional deviation during transportation. This provides a similar effect.

[0065] Other Examples In the first to third embodiments, a UI for setting one parameter has been described as an example of a UI panel for setting inspection parameters for print misalignment. However, as shown in Fig. 18, for example, a UI for independently setting parameters corresponding to vertical and horizontal print misalignment may be used, in which the setting range of the inspection parameters is controlled independently for the vertical and horizontal directions.

[0066] Also, the minimum detectable positional deviation may be calculated by taking into account the skew of the paper. Figure 19 shows the relationship between the image reading device 105 and the paper when the paper is skewed. Here, the maximum skew angle of the paper is θ. In this case, the minimum detectable positional deviation is calculated as D min =x and perform the inspection parameter setting range control process described in the first to third embodiments to obtain the same effect. X can be calculated by the formula (2).

[0067]

number

[0068] Here, W p is the width of the paper, H p is the height of the paper, W s is the maximum reading width of the image reader 105.

[0069] The present invention can also be realized by a process in which a program for realizing one or more functions of the above-mentioned embodiments is supplied to a system or device via a network or a storage medium, and one or more processors in a computer of the system or device read and execute the program. The present invention can also be realized by a circuit (e.g., ASIC) for realizing one or more functions. [Explanation of symbols]

[0070] 201 Inspection image acquisition unit 202 Reference image acquisition unit 203 Inspection parameter setting range control section 204 Inspection Settings 205 Inspection Processing Section 206 Result output section

Claims

1. a setting means for setting conditions for detecting a misalignment of a print position in a printed matter; an inspection means for inspecting the printed matter based on an inspection target image obtained by reading the printed matter and the conditions; having The conditions are set within a range determined by upper and lower limits, An image processing device characterized in that the settable range of the conditions when the width of the printed material is larger than the readable width of the printing medium has an upper limit equal to the width of the printed material and a lower limit larger than the settable range when the width of the printed material is smaller than the readable width.

2. 2. The image processing apparatus according to claim 1, wherein said inspection means performs the inspection by comparing said inspection target image with a reference image.

3. 3. The image processing apparatus according to claim 1, wherein the setting unit sets the settable range by changing a predetermined range when the width of the printed matter is larger than the readable width.

4. 4. The image processing apparatus according to claim 1, wherein the settable range is expressed by a level of deviation of the print position.

5. 5. The image processing device according to claim 4, wherein the setting means sets the settable range so that when the width of the printed matter is greater than the readable width, the magnitude of the printing position shift corresponding to the level is greater than when the width of the printed matter is smaller than the readable width.

6. 6. The image processing device according to claim 1, wherein the setting means sets the settable range so that the magnitude of the print position misalignment set to an inspection level capable of inspecting the smallest position misalignment becomes the minimum amount of position misalignment that can be detected.

7. 7. The image processing apparatus according to claim 1, wherein the setting means sets the conditions independently for the length and width of the printed matter.

8. a conveyance position deviation amount acquisition unit that acquires a conveyance position deviation amount of the printed matter, 8. The image processing apparatus according to claim 1, wherein the setting unit sets the condition based on the readable width, the width of the printed matter, and the amount of deviation in conveying position.

9. A program for causing a computer to function as each of the means of the image processing device according to any one of claims 1 to 8.

10. A setting step of setting conditions for detecting misalignment of a print position in a printed matter; an inspection step of inspecting the printed matter based on an inspection target image obtained by reading the printed matter and the conditions; having The conditions are set within a range determined by upper and lower limits, An image processing method characterized in that the settable range of the conditions when the width of the printed matter is larger than the readable width of the printing medium has an upper limit equal to the width of the printed matter and a lower limit larger than the settable range when the width of the printed matter is smaller than the readable width.

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