JP2003094627A - Apparatus for inspecting ink jet printing part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus for inspecting an ink jet printing part which can be used regardless of the type of an ink jet printer, can detect ink droppings in printed patterns and eliminate the need for a designated mark for detecting missing ink. SOLUTION: The apparatus for inspecting the ink jet printing part is provided with a bit map image forming means for forming the bit map image from an image describing file wherein an image is printed by the ink jet printer, a printed matter pickup means for forming a pickup image by picking up the printed matter printed by the ink jet printer, and a defect extracting means for extracting defects in the printing based on the bit map image and the pickup image.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of automatically inspecting printed matter. In particular, the present invention relates to an inkjet printing unit inspection device for inspecting a portion of a printed matter on which variable information is printed by an ink jet printer.

[0002]

2. Description of the Related Art Inkjet printers capable of printing variable information at high speed are widely used as printing apparatuses for printing personal information required for direct mail.

[0003]

However, in the ink jet printer, defects such as "ink dripping" and "ink loss" in printing are likely to occur. Therefore, there is a proposal for automatic inspection, but it has not been widely put into practical use.

For example, in Japanese Patent Laid-Open No. 9-277670, bitmap image data input by an ink jet printer is used as reference image data.
Therefore, it is necessary to design it as a dedicated inspection device according to the type of inkjet printer. Further, in order to detect ink loss, it is necessary to input an inspection target image having a resolution equal to or greater than the streak width generated thereby and having no distortion. Further, for example, Japanese Patent Laid-Open No. 10-10
No. 0412 cannot detect ink dripping in the printed pattern. Further, in order to detect ink loss, a dedicated mark corresponding to the entire print width is required.

The present invention has been made to solve such problems. An object of the present invention is to provide an inkjet printing unit inspection device that can be used regardless of the type of inkjet printer, can detect ink dripping in a printed pattern, and does not require a dedicated mark to detect ink loss. is there.

[0006]

The above problems can be solved by the present invention described below. That is, the inkjet printing unit inspecting apparatus according to claim 1 of the present invention includes a bitmap image generating unit that generates a bitmap image from a print image description file that describes an image to be printed by the inkjet printer, and the inkjet printer. Printed matter image pickup means for picking up a printed matter printed to generate a picked-up image, and defect extraction means for extracting a defect in the printing based on the bitmap image and the picked-up image are provided. It is a thing.

According to the present invention, the bitmap image is generated from the print image description file describing the image to be printed by the inkjet printer by the bitmap image generating means, and the printing is performed by the inkjet printer by the printed matter imaging means. The printed matter is picked up, a picked-up image is generated, and a defect in the printing is extracted by the defect extraction means based on the bitmap image and the picked-up image. Here, the print image description file is a compatible data file that is not affected by the type of printer. Therefore, an inkjet printing unit inspection device that can be used regardless of the type of inkjet printer is provided.

According to a second aspect of the present invention, there is provided an ink jet printing portion inspection apparatus according to the first aspect, wherein the defect is ink dripping caused by excess ink in the ink jet printer. It was done. According to the present invention, ink dripping is detected.

An ink jet printing portion inspection apparatus according to a third aspect of the present invention is the ink jet printing portion inspection apparatus according to the first or second aspect, in which the defect is ink loss caused by nozzle clogging in the ink jet printer. It was done as it was. According to the present invention, ink loss is detected.

An ink jet printing portion inspection apparatus according to a fourth aspect of the present invention is the ink jet printing portion inspection apparatus according to any one of the first to third aspects, wherein the defect extracting means is an image area portion in the bitmap image. To generate a variable data mask image, to generate a background image threshold image by emphasizing the contour in the background image input image, the absolute value of the difference between the background image input image and the captured image An absolute value image of the difference is calculated to generate a variable data input image by performing size comparison of corresponding pixels of the background pattern threshold image and the absolute value image of the difference to generate a variable data input image, and the variable data portion mask image and the The ink dripping is extracted by calculating a logical product of variable data input images to generate an ink dripping image. According to the present invention, ink dripping in a printed pattern is detected.

An ink jet printing portion inspection apparatus according to a fifth aspect of the present invention is the ink jet printing portion inspection apparatus according to any one of the first to fourth aspects, wherein the defect extracting means includes the bitmap image and the captured image. The process for cutting out the variable data portion in 3 is compared with each of the cut out variable data portions to extract the ink loss. That is, since the ink loss detection is performed by comparison, a dedicated mark is not required, and since only the variable data portion is compared, the processing speed is high. Therefore, according to the present invention, a dedicated mark is not required,
Ink loss is detected at high speed.

According to a sixth aspect of the present invention, there is provided an ink jet printing portion inspection device according to the fifth aspect, wherein the defect extracting means is an area defined by layout data in the bitmap image. From the bitmap data to generate a variable data portion inspection reference image for each field, expand the image portion of the bitmap data to generate a variable data portion mask image, and generate a negative image of the variable data portion mask image. /
A positive product is inverted and a logical product is calculated from the captured image to generate a variable data portion cutout image, and a logical sum of the variable data portion cutout image and the variable data portion cutout image 54 is calculated to obtain a variable data portion cutout image. To generate a variable data portion cutout image by extracting a predetermined registered color from the variable data portion cutout image, and cutting out the area defined by the layout data from the variable data portion cutout image. By generating an inspection target image, a process of cutting out the variable data portion in the bitmap image and the captured image is performed. According to the present invention, the variable data portion in the bitmap image and the captured image is cut out in order to detect ink loss.

An ink jet printing portion inspection apparatus according to a seventh aspect of the present invention is the ink jet printing portion inspection apparatus according to the fifth or sixth aspect, wherein the defect extracting means is
Pixel values are integrated in the Y-axis direction with respect to the variable data portion inspection reference image to generate inspection reference X-axis projection data, and a portion of the inspection reference X-axis projection data having a value of 0 is extracted to extract inspection reference zero. Data is generated, pixel values are integrated in the Y-axis direction with respect to the variable data portion inspection target image to generate inspection target X-axis projection data, and the X-axis position and X-axis magnification of the inspection target X-axis projection data are generated. And within a predetermined range to calculate the degree of coincidence of the data string with the inspection reference X-axis projection data, and calculate the X-axis position and the X-axis magnification that give the maximum degree of coincidence, and calculate the X-axis position and X-axis. Corrected inspection target X by correcting the positional deviation and magnification error of the inspection target X-axis projection data based on the axial magnification
Axial projection data is generated, the corrected inspection target X-axis projection data is binarized by a threshold value close to 0, inspection target zero extraction data is generated, and the inspection reference is extracted from the inspection target zero extraction data. By removing the zero part common to the zero extraction data and the zero extraction data to be inspected and generating the ink missing data, the process of comparing the cut-out variable data parts is performed. According to the present invention, a process of comparing the cut-out variable data portions is performed in order to detect ink loss.

Further, an ink jet printing portion inspection apparatus according to an eighth aspect of the present invention is the ink jet printing portion inspection apparatus according to any one of the first to seventh aspects, wherein the printed matter is based on the defect extracted by the defect extracting means. A quality determination means for performing quality determination of is provided. According to the present invention, the quality of printed matter is determined.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Next, embodiments of the present invention will be described. FIG. 1 shows an example of the configuration of the inkjet printing unit inspection apparatus of the present invention. FIG. 1 shows not only the parts of the invention, but also the surrounding parts concerned. In FIG. 1, 1 is a camera, 2 is an image input unit, 3 is an inspection processing unit, 4 is a control unit, 5 is bitmap creation software, 6 is a storage device (HDD), 20 is variable data, 21
Is a print image description file specific to the printer, 22
Is a bitmap image data, 23a and 23b are a set of a bitmap image file and a layout information file, 101 is layout editing software, 102 is a server, 103 is a printer controller, 104 is a printer head, and 200 is a printed matter.

First, the construction of the ink jet printing portion inspection apparatus of the present invention will be described. The camera 1 is an imaging unit that images a printed matter printed by an inkjet printer and outputs an imaging signal. On the printed matter 200, a fixed information printed portion printed in a printing process such as offset printing or flexographic printing (see FIG. 2A).
And a variable information printing portion (see FIG. 2B) where printing is performed by the inkjet printer. The camera 1 images the entire range of the printed matter 200, or at least the range including the variable information print portion.

The image input section 2 receives an image pickup signal output from the camera 1, performs A / D (analog-to-digital) conversion to generate a picked-up image, and stores the picked-up image in a memory of the image input section 2. Remember.

The inspection processing section 3 performs a defect extraction process and a pass / fail judgment process. The defect extraction process is performed by the storage device (HDD).
The set 23b of the bitmap image file and the layout information file stored in 6 and the captured image stored in the image input unit 2 are input to the memory of the inspection processing unit 3 and compared with each other to cause ink dripping, ink bleeding, etc. This is a process for extracting defects. The quality determination process is a process of determining the quality of the printed matter 200 based on the extracted defects.

The control section 4 is a section for controlling the overall operation of the inkjet printing section inspection apparatus. For example, a synchronous control when capturing an image of the printed matter 200 on which printing is performed, a set 23b of a captured image obtained by capturing, a bitmap image file, and a layout information file.
It performs synchronous control, etc., that maintains the correspondence relationship with. Also,
The inspection result is output to an external system via the control unit 4.

The bitmap creation software 5 carries out a process of generating a set 23a of bitmap image file and layout information file from a compatible print image description file which is not affected by the type of printer. The compatible print image description file is generated by the server 102 from the printer-specific print image description file 21 and stored in the server 102. The set 23a of the bitmap image file and the layout information file is a bitmap image file corresponding to the pixel density of the captured image obtained by capturing with the camera 1.

The storage device (HDD) 6 stores a set 23a of a bitmap image file and layout information file generated by the bitmap generation software 5.

Next, a process of generating data to be printed by the ink jet printer will be described. The layout editing software 101 generates a print image description file 21 unique to the printer from the variable data 20. In the variable information printing portion of the printed matter 200, individual data of each printed matter 200 is printed. The individual data includes the destination of direct mail, name, usage fee details of the month, billing content, and the like. Variable data 2
0 is data in which those individual data are set as one set (record), and the records are arranged in order by the number of the printed matter 200 to be printed. Layout editing software 1
Reference numeral 01 performs an edit process for adding edit information such as layout (print position), print size, typeface, etc. to individual data in the record, and also performs a process for converting the variable data 20 into a print image file unique to the printer. .

The server 102 is a data server that stores the print image description file 21 unique to the printer and outputs print data to the ink jet printer. The server 102 also generates and stores a compatible print image description file that is not affected by the printer type from the printer-specific print image description file 21. The compatible print image description file is output to the above-described bitmap creation software 5.

The printer controller 103 generates bitmap image data 22 from the print image description file 21 unique to the printer. The bitmap image data 22 is bitmap image data corresponding to the print resolution of the inkjet printer.

The printer head 104 inputs the bitmap image data 22 and prints on the printed matter 200. At this time, the printer controller 103 controls the printing so that the printing and the feeding of the printed matter 200 are synchronized.

Next, the operation of the ink jet printing portion inspection apparatus of the present invention having the above-mentioned structure will be described. The inkjet printing unit inspection apparatus of the present invention inspects defects "ink dripping" and "ink loss" that occur when printing is performed by an inkjet printer (see FIG. 2C). The "ink missing" is also called "clogging" because it is caused by the nozzle clogging in the inkjet.

First, the process for detecting ink dripping will be described with reference to FIGS. FIG. 3 and FIG. 4 show the flow of processing divided into three sections, a left column, a central column, and a right column. The left column shows the pre-processing performed when the variable data 20 is submitted. The center column shows the pre-processing performed immediately before printing the variable information. The right column shows real-time processing while printing variable information.

In the preprocessing (left column) performed when the variable data 20 shown in FIGS. 3 and 4 is submitted, the inspection processing unit 3 extracts the variable data portion mask image 32 from the variable data bitmap data 31. To generate. The variable data bitmap data 31 is generated by the bitmap generation software 5 from the printer image description file 21 specific to the printer so as to match the resolution of the image captured by the camera 1. That is, the set 2 of the bitmap image file and the layout information file described above.
It is the same as 3a. In addition, the variable data mask image 32
Is an image obtained by expanding the dark portion (image portion) in the variable data bitmap data 31.

Further, in the preprocessing (center column) performed immediately before printing the variable information in FIG. 3, the inspection processing unit 3
Is the background pattern input image 33 to the background pattern threshold image 3
4 is generated. The background pattern input image 33 is a captured image obtained by the camera 1 capturing the printed matter 200 before the variable data is printed. In addition, the background pattern threshold image 34
Is an image obtained by further binarizing the image on which the outline (edge) is emphasized in the background pattern input image 33 with a predetermined threshold value.

Further, in the real-time processing (right column) while printing the variable information shown in FIG. 3, the inspection processing section 3 produces the absolute value image 36 of the difference between the background pattern input image 33 and the inspection target image 35. To generate. Inspection target image 35
Is the printed matter 200 to be inspected after printing the variable data.
Is a captured image obtained by the camera 1 capturing. The absolute value image 36 of the difference is the background pattern input image 33 and the inspection target image 35.
Is an image in which the absolute value of the difference between the pixel values of the pixels corresponding in position is calculated, and the absolute value is used as the pixel value of the pixel corresponding in position.

Next, in the real-time processing (right column) while printing the variable information shown in FIGS. 3 and 4,
The inspection processing unit 3 generates the variable data input image 37 from the base pattern threshold image 34 and the absolute value image 36 of the difference. In the variable data input image 37, the pixel values of the pixels that are positionally corresponding in the base image Shikiichi image 34 and the absolute value image 36 of the difference are compared, and when the pixel value of the pixel of the absolute value image 36 of the difference is large. An image in which the pixel value is the pixel value of the pixel corresponding to the position.

Next, in the real-time processing (right column) while printing the variable information shown in FIG. 4, the inspection processing unit 3 extracts the ink dripping image 38 from the variable data mask image 32 and the variable data input image 37. To generate. The ink dripping image 38 calculates the logical product of the pixel values of the pixels that correspond positionally in the variable data area mask image 32 and the variable data input image 37, and calculates the logical product as the pixel value of the pixel that corresponds positionally. Image. The ink dripping image 38 is an image in which the ink dripping is extracted from the inspection target image 35.

Next, in the real-time processing (right column) while printing the variable information shown in FIG. 4, the inspection processing unit 3 determines the printed matter 20 based on the ink dripping image 38.
Pass / fail determination processing for determining pass / fail of 0 is performed. For example,
The number of pixels of the ink dripping portion in the ink dripping image 38, that is, the area is calculated. When the area of the ink dripping is within a predetermined allowable range, it is determined as “good”, and the area of the ink dripping is within the predetermined allowable range. If it exceeds, it is determined to be "defective".

The process of detecting ink dripping has been described above. Next, a process for detecting ink loss (clogging) will be described with reference to FIGS. FIG. 5 is an explanatory diagram (first half) of the process of cutting out the variable data portion in the inspection reference image and the inspection target image. Further, FIG. 6 is an explanatory diagram (second half) of the process of cutting out the variable data portion in the inspection reference image and the inspection target image. FIG. 7 is an explanatory diagram of a process of comparing the variable data portion of the inspection reference image and the variable data portion of the inspection target image to extract ink loss (clogging). FIG. 8 corrects the geometric distortion of the image to be inspected in the process (the process of FIG. 7) of comparing the variable data part of the inspection reference image with the variable data part of the image to be inspected to extract ink loss (clogging). It is an explanatory view of processing.

First, the process of cutting out the variable data part in the inspection reference image and the inspection object image will be described with reference to FIGS. FIG. 5 shows the flow of processing divided into two parts, a left column and a right column. The left column shows the pre-processing performed when the variable data 20 is submitted. The right column shows real-time processing while printing variable information.

In the pre-processing (left column) performed when the variable data 20 shown in FIGS. 5 and 6 is submitted, the inspection processing unit 3 determines from the variable data layout data 51 and the variable data bitmap data 52. The variable data portion inspection reference image 53 for each field is generated. The variable data bitmap data 52 and the variable data layout data 51 are generated by the bitmap generation software 5 from the printer image description file 21 specific to the printer so as to match the resolution of the image captured by the camera 1. That is, it is the same as the set 23a of the bitmap image file and the layout information file described above. In the variable data part inspection reference image 53 for each field, the area defined by the layout data 51 of the variable data is used as the bitmap data 5 of the variable data.
It is an image cut out from 2.

In the pre-processing (left column) performed when the variable data 20 shown in FIG. 5 is submitted, the inspection processing unit 3 generates the variable data mask image 54 from the variable data bitmap data 52. To do. The variable data part mask image 54 is the bitmap data 5 of the variable data.
2 is an image obtained by expanding the dark area (image area) in FIG.
That is, it is the same as the variable data area mask image 32 described above.

In the real-time processing (right column) while printing the variable information shown in FIG. 5, the inspection processing unit 3 extracts the variable data portion cutout image 56 from the variable data portion mask image 54 and the inspection target image 55. To generate.
The inspection target image 55 is a captured image obtained by the camera 1 capturing the printed matter 200 to be inspected after printing the variable data. The variable data portion cut-out image 56 calculates the logical product of the negative / positive inverted image of the variable data portion mask image 54 and the pixel value of the pixel positionally corresponding in the inspection target image 54, and calculates the logical product at that position. It is an image having pixel values of pixels corresponding to each other. Note that (pixel value of negative image) =
There is a relation of (maximum value as pixel value)-(pixel value of positive image).

Next, in the real-time processing (right column) while printing the variable information shown in FIGS. 5 and 6,
The inspection processing unit 3 generates a variable data portion cutout image 57 from the variable data portion mask image 54 and the variable data portion cutout image 56. Variable data section cutout image 57
Is an image in which the logical sum of the pixel values of the pixels that correspond positionally in the variable data mask image 54 and the variable data cut-out image 56 is calculated, and the logical sum is used as the pixel value of the pixel that corresponds in position. Is.

Next, in the real-time processing (right column) while printing the variable information shown in FIG. 6, the inspection processing unit 3 generates the variable data portion cutout image 58 from the variable data portion cutout image 57. The variable data portion cutout image 58 is an image in which the color of variable data printing is registered in advance, and pixels of a color close to that color are extracted from the variable data portion cutout image 57. For example, for a color image, SQRT ((r-
Pixels having a value of r0) ^ 2 + (g-g0) ^ 2 + (b-b0) ^ 2) smaller than a predetermined value are extracted.

Next, in the real-time processing (right column) while printing the variable information shown in FIG. 6, the inspection processing unit 3 uses the layout data 51 of the variable data and the cut-out image 58 of the variable data portion for each field. The variable data portion inspection target image 59 is generated. The variable data portion inspection target image 59 is the layout data 5 of the variable data.
It is an image obtained by cutting out the area defined by 1 from the variable data portion cutout image 58.

The process of cutting out the variable data portion of each of the inspection reference image and the inspection object image in the ink missing (clogging) detection process has been described above. Next, compare the variable data parts of these and remove ink (clogging).
The process of extracting the will be described with reference to FIG.

First, the inspection processing section 3 determines the variable data section inspection reference image 71 (same as the variable data section inspection reference image 53).
, The pixel values are integrated in the Y-axis direction to generate inspection reference X-axis projection data 72.

Next, the inspection processing unit 3 extracts a portion having a value of 0 in the inspection reference X-axis projection data 72 and generates inspection reference zero extraction data 73.

Next, the inspection processing unit 3 causes the variable data portion inspection target image 74 (the same as the variable data portion inspection target image 59).
The pixel values are integrated in the Y-axis direction to generate the inspection target X-axis projection data 75.

Next, the inspection processing unit 3 changes the X-axis position and the X-axis magnification of the inspection target X-axis projection data 75 within a predetermined range to determine the degree of coincidence of the data string with the inspection reference X-axis projection data 72. Is calculated, and the X-axis position and the X-axis magnification that give the maximum degree of coincidence are calculated.

This calculation will be described with reference to FIG. Figure 8
3, the x-axis, the y-axis, and the z-axis are the enlargement ratio (X-axis magnification), the degree of coincidence, and the offset position (X-axis position), respectively.
Assume a dimensional space. The degree of coincidence y is y with the enlargement ratio (X axis magnification) x and the offset position (X axis position) z as variables.
= F (x, z) and forms a curved surface in this three-dimensional space. Maximum value on that surface,
That is, the enlargement ratio (X-axis magnification) giving the maximum value of the coincidence y
The values of x and the offset position (X-axis position) z are the X-axis position and the X-axis magnification stored in step S14.

Next, the inspection processing unit 3 corrects the positional deviation and magnification error of the inspection object X-axis projection data 75 based on the X-axis position and the X-axis magnification, and the corrected inspection object X-axis projection data 76. To generate.

Next, the inspection processing unit 3 outputs the inspection target X-axis projection data 76 corrected by the threshold value close to 0 to 2
It is digitized and the inspection target zero extraction data 77 is generated.

Next, the inspection processing unit 3 removes the zero portion common to the inspection reference zero extraction data 73 and the inspection target zero extraction data 77 from the inspection target zero extraction data 77,
Ink missing data 78 is generated. The ink missing data 78 is data for detecting (extracting) ink missing (clogging) in the inspection target image 35.

Next, the inspection processing section 3 performs a quality determination process for determining the quality of the printed matter 200 based on the ink missing data 78. For example, when ink loss (clogging) is not detected in the ink loss data 78, it is determined as “good”, and when ink loss (clogging) is detected, it is determined as “defective” regardless of the quantity of ink loss. judge.

[0052]

As described above, according to the inkjet printing unit inspection apparatus of the first aspect of the present invention, there is provided an inkjet printing unit inspection apparatus which can be used regardless of the type of the inkjet printer. Further, according to the inkjet printing portion inspection apparatus of the second aspect of the present invention, it is possible to detect ink dripping. Further, according to the inkjet printing portion inspection apparatus of the third aspect of the present invention, it is possible to detect ink loss. Further, according to the inkjet printing portion inspection apparatus of the fourth aspect of the present invention, it is possible to detect ink dripping in the printed pattern.
Further, according to the inkjet printing unit inspection apparatus of the fifth aspect of the present invention, it is possible to detect ink loss at high speed without the need for a dedicated mark. Further, according to the inkjet printing portion inspection apparatus of the sixth aspect of the present invention, the variable data portion in the bitmap image and the captured image can be cut out in order to detect ink loss. Further, according to the ink jet printing portion inspection apparatus of the seventh aspect of the present invention, it is possible to compare the cut out variable data portions in order to detect ink loss. Further, according to the inkjet printing portion inspection apparatus of the eighth aspect of the present invention, it is possible to judge the quality of the printed matter.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of a configuration of an inkjet printing unit inspection apparatus of the present invention.

FIG. 2 is a diagram showing a fixed information printed portion, a variable information printed portion, and defects “ink dripping” and “ink loss” in a printed matter.

FIG. 3 is an explanatory diagram (first half) of a process for detecting ink dripping.

FIG. 4 is an explanatory diagram (second half) of a process for detecting ink dripping.

FIG. 5 is an explanatory diagram (first half) of a process of cutting out a variable data portion in an inspection reference image and an inspection target image.

FIG. 6 is an explanatory diagram (second half) of the process of cutting out the variable data portion in the inspection reference image and the inspection target image.

FIG. 7 is an explanatory diagram of a process for extracting a missing ink (clogging) by comparing the variable data part of the inspection reference image with the variable data part of the inspection target image.

FIG. 8 corrects the geometric distortion of the image to be inspected in the process (the process of FIG. 7) of extracting the missing ink (clogging) by comparing the variable data part of the inspection reference image with the variable data part of the image to be inspected. It is an explanatory view of processing.

[Explanation of symbols]

1 camera 2 image input unit 3 inspection processing unit 4 control unit 5 bitmap creation software 6 storage device (HDD) 20 variable data 21 printer specific print image description file 22 bitmap image data 23a, 23b bitmap image file and layout information File set 31 Variable data bitmap data 32 Variable data area mask image 33 Underlay pattern input image 34 Underlay pattern threshold image 35 Inspection target image 36 Difference absolute value image 37 Variable data input image 38 Ink droop image 51 Variable data Layout data 52 variable data bitmap data 53, 71 variable data portion inspection reference image 54 for each field variable data portion mask image 55 inspection target image 56 variable data portion cutout image 57 variable data portion cutout image 58 Variable data portion cutout image 59, 74 Variable data portion for each field Inspection target image 72 Inspection reference X-axis projection data 73 Inspection reference zero extraction data 75 Inspection target X-axis projection data 76 Corrected inspection target X-axis projection data 77 Inspection target Zero extraction data 78 Ink missing data 101 Layout editing software 102 Server 103 Printer controller 104 Printer head 200 Printed matter

Claims (8)

[Claims] 1. A bitmap image generating means for generating a bitmap image from a print image description file that describes an image to be printed by an inkjet printer, and a picked-up image of a printed matter printed by the inkjet printer. An inkjet printing unit inspecting apparatus comprising: a printed matter image capturing unit that generates a print defect; and a defect extracting unit that extracts a defect in the printing based on the bitmap image and the captured image. 2. The inkjet printing unit inspection apparatus according to claim 1, wherein the defect is ink dripping caused by excess ink in the inkjet printer. 3. The inkjet printing unit inspection apparatus according to claim 1 or 2, wherein the defect is ink deficiency caused by nozzle clogging in the inkjet printer. 4. The ink jet printing portion inspection apparatus according to any one of claims 1 to 3, wherein the defect extracting means comprises:
The variable area mask image is generated by expanding the image part in the bitmap image, the outline in the background pattern input image is emphasized to generate a background pattern threshold image, and the background pattern input image and the background pattern input image are generated. An absolute value image of the difference is generated by calculating the absolute value of the difference between the captured images, and a variable data input image is generated by performing a size comparison of the corresponding pixels of the base pattern threshold image and the absolute value image of the difference, An ink jet printing unit inspection apparatus, wherein the ink dripping is extracted by calculating a logical product of the variable data area mask image and the variable data input image to generate an ink dripping image. 5. The apparatus for inspecting an ink jet printing section according to claim 1, wherein the defect extracting means comprises:
An inkjet printing unit inspection apparatus, wherein the process for cutting out the variable data portion in the bitmap image and the captured image is compared with each of the cut out variable data portions to extract the ink drop. 6. The inkjet printing unit inspection apparatus according to claim 5, wherein the defect extraction unit cuts out an area defined by layout data in the bitmap image from the bitmap data and inspects the variable data portion for each field. A reference image is generated, the image area of the bitmap data is expanded to generate a variable data mask image, the negative / positive of the variable data mask image is inverted, and the logical product with the captured image is calculated. Then, a variable data part cutout image is generated, a logical sum of the variable data part cutout image and the variable data part cutout image is calculated to generate a variable data part cutout image, and a predetermined registration color is generated from the variable data part cutout image. To extract a variable data part cutout image, and change the area defined by the layout data to the variable By generating a variable data portion inspection object image by cutting out from over data unit cutout image, an inkjet printing unit inspection device and performs the process of cutting out the variable data portion of the bitmap image and the captured image. 7. The inkjet printing unit inspection apparatus according to claim 5, wherein the defect extracting means integrates pixel values in the Y-axis direction with respect to the variable data area inspection reference image and inspects the inspection reference X-axis. Data is generated and its inspection standard X
A portion having a value of 0 is extracted from the axial projection data to generate inspection reference zero extraction data, and pixel values are integrated in the Y-axis direction with respect to the variable data portion inspection target image to generate inspection target X-axis projection data. , The X-axis position and the X-axis magnification of the inspection target X-axis projection data are changed within a predetermined range to calculate the degree of coincidence of the data string with the inspection reference X-axis projection data, and the X-axis that gives the maximum degree of coincidence The position and the X-axis magnification are calculated, and the positional deviation and magnification error of the inspection-target X-axis projection data are corrected based on the X-axis position and the X-axis magnification to generate the corrected inspection-target X-axis projection data. The corrected inspection target X-axis projection data is binarized by a threshold value close to the value to generate inspection target zero extraction data, and the inspection reference zero extraction data and the inspection target zero are generated from the inspection target zero extraction data. Common to extracted data By removing the zero part to generate ink dropout data, ink jet printing part inspection device and performs the process of comparing the variable data portion of each of the cut out. 8. The inkjet printing unit inspection apparatus according to claim 1, further comprising a quality determination unit that determines quality of the printed matter based on the defect extracted by the defect extraction unit. It was done.
According to the present invention, the quality of printed matter is determined.