JPH09131951A - Printing quality judging device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To carry out automatically the inspection of total numbers by determining whether a printed matter is good or not based on a mask pattern data from a print image data and a sensed image data provided by picking up the image of the printed matter. SOLUTION: A printing data 1 is input into a raster image processor 2, and a master image data is formed by the raster image processor 2. The raster image data is input into a printing quality judging device 4, and the mask pattern data is formed by a mask pattern formation section of the printing quality judging device 4. The images of printed matters 5a and 5b are picked up by an image pickup camera 6 based on the master image data. Whether a printed surface formed by a printer 3 is good or not is judged for the printed matters 5a and 5b based on the mask pattern data and the sensed image data in a comparison judgement section of the printing quality judging device 4, and its inspection results are output.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for determining print quality of printed matter. In particular, the present invention relates to a printing device that prints variable information based on input data, for example, a printing quality determination device for a portion printed by a laser printer, an inkjet printer, a thermal printer, or the like.

[0002]

2. Description of the Related Art Recently, a catalog using a variable information printing device, a destination for direct mail, a name, an ID number,
Widely used for printing messages, logos, marks, illustrations, tint blocks, and images. Visual inspection by humans is the main inspection for whether or not such variable information is printed accurately, and the total inspection has a large work load, and it is inevitable that defects will be overlooked. As an automatic inspection device for printed matter, for example, a device is known in which image data for comparison is registered in advance, and the registered image data is compared with the detected image data captured by a camera or the like to determine whether the image is good or bad.

[0003]

However, the above-mentioned automatic inspection apparatus is an apparatus applied in the case of printing using a printing plate for printing a fixed image, and an electrophotographic system (for printing a variable image based on digital data). Laser printer), inkjet method (inkjet printer)
In case of printing by etc., it cannot be applied as it is.
In the case of applying it by force, since the inspection contents are different every time, the comparison patterns have to be registered for the number of data items, and there is a problem that a great load occurs in data creation and input work.

Therefore, an object of the present invention is to eliminate the problems caused by human inspection such as human burden, work load, and mixing of defective products into products, and solve the problem that the reference image is different for each printed matter. An object of the present invention is to provide a print quality determination device that automatically performs 100% inspection.

[0005]

The above objects are achieved by the present invention described below. That is, the present invention relates to a "mask pattern generation unit that generates mask pattern data from print image data, an imaging unit that captures detection image data by imaging a printed matter printed based on the print image data, and the mask pattern data. A print quality determination device having a comparison / determination unit that determines the quality of a printed material based on the detected image data ”. According to the present invention,
The quality of the printed matter to be printed based on the print image data is determined based on the mask pattern data generated from the print image data and the detected image data obtained by imaging the printed matter. Therefore, there is provided a print quality determination device capable of automatically performing an inspection even if a print image is different for each printed matter.

According to the present invention, "the mask pattern generation section has a vertical / horizontal magnification conversion means, and the vertical / horizontal magnification conversion means is
A print quality determination device that converts at least one aspect ratio of the print image data or the detected image data so that the print image and the detected image overlap. According to the present invention, even when the vertical and horizontal arrangement densities of pixels forming print image data and the vertical and horizontal arrangement densities of pixels forming detected image data are different, both pixels are converted by converting the vertical and horizontal magnifications. The vertical and horizontal array densities of can be matched.
That is, both pixels at the same array position can have a correspondence relationship.

According to the present invention, "the mask pattern generating section has a binarizing means, an expansion processing means, and a mask processing means, and the binarizing means binarizes the print image data with a predetermined threshold value. To generate binarized print pattern data, the expansion processing means performs expansion processing on the binarized print pattern data to generate expansion pattern data, and the mask processing means masks the outside of the inspection region. It is a print quality determination device for generating expanded mask pattern data by synthesizing mask pattern data outside the inspection area, which is data, and the expanded pattern data. According to the present invention, expanded pattern data, which is a pattern that is printed by the print image data and substantially covers the portion where the printing ink is attached, is generated, and the mask pattern data outside the inspection area is combined with it. Therefore, it is possible to mask the outside of the inspection area and the portion where the printing ink adheres by the expanded mask pattern data. To put it the other way around, it is possible to extract the portion of the inspection area where the printing ink does not adhere.

According to the present invention, "the mask pattern generating section has a binarizing means, a contraction processing means, an inversion processing means, and a mask processing means, and the binarizing means predetermines the print image data. Binarization is performed with the threshold value of 2 to generate binarized print pattern data,
Contraction processing of the digitized print pattern data is performed to generate contraction pattern data, the reversal processing means performs reversal processing of the contraction pattern data to generate reversal pattern data, and the mask processing means is outside the inspection area. Is a print quality judging device for synthesizing mask pattern data outside the inspection area, which is data for masking, and the inversion pattern data to generate contraction mask pattern data. According to the present invention, the print image data is printed,
Shrinkage pattern data, which is a pattern substantially included in the portion where the printing ink adheres, is generated, and the shrinkage pattern data is inverted to generate inverted pattern data, which is combined with the mask pattern data outside the inspection area. Therefore, the contraction mask pattern data can be used to mask the outside of the inspection area and the portion where the printing ink does not adhere. Conversely, it is possible to extract the portion of the inspection area to which the printing ink adheres.

According to the present invention, "the comparison / determination unit has a summing calculation unit and a comparison unit, and the summing calculation unit is a pixel of the detected image data existing outside the mask area of the expanded mask pattern data. It is a print quality judging device which calculates the sum of the values and compares the sum with a predetermined value and outputs an excessive defect signal when the sum is large. " According to the present invention, the sum total calculation means calculates the sum total of the pixel values of the detected image data existing outside the mask area of the expanded mask pattern data. When printing is performed normally, printing is not performed outside the mask area, so the sum of pixel values is small. On the other hand, when printing is performed outside the mask area, the total sum of pixel values becomes large. The comparison means compares the total sum with a predetermined value, and when the total sum is large, an excessive failure signal is output.

According to the present invention, "the comparison / determination unit has a missing pixel sum total calculation means and a comparison means, and the sum total calculation means includes the detected image data existing outside the mask area of the contraction mask pattern data. Of the pixel omission, and the comparing means compares the total with a predetermined value and outputs an under-defective signal when the total is large. " According to the present invention, the total pixel omission sum calculation means calculates the total pixel omission of the detection image data existing outside the mask area of the contraction mask pattern data. When printing is performed normally, printing is performed outside the mask area, so the total pixel omission is small. On the other hand, when there is a printing omission outside the mask area, the total pixel omission becomes large. The comparison means compares the total sum with a predetermined value, and when the total sum is large, an under-defective signal is output.

The present invention also relates to a "print quality judging device having an inspection condition setting unit for setting at least conditions for expansion processing by the expansion processing means and conditions for contraction processing by the contraction processing means based on a test pattern". Is.
According to the present invention, the inspection condition setting unit sets the expansion processing condition and the contraction processing condition based on the test pattern. Since this setting is performed while the print quality determination device is installed, proper setting can be easily performed.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described with reference to embodiments. FIG. 1 is a diagram showing a configuration of a print quality determination device of the present invention and its peripheral devices. In FIG. 1, 1 is print data, 2 is a raster image processor, 3 is a printer,
Reference numeral 4 is a print quality determination device, 5a and 5b are printed matter, 6 is an imaging camera, and 7 is a position detection sensor. The print data 1 is code data such as text data or Postscript data that describes the position and inclination of a sentence or a figure. Further, the print data 1 has a data structure in which a record is formed by using the content to be printed on one printed matter as one block of data, and the records are arranged in the printing order by the number of printed matters. The raster image processor 2 receives the print data 1 and generates raster image data. The raster image data is the print data 1 expanded into a bitmap.
When output to a printer, it is also called print image data. In the present invention, the raster image data and the print image data are the same.

This raster image data is output from the raster image processor 2 to the printer 3 and the print quality judging device 4. The raster image data input by the printer 3 is printed on the printing paper by the printer 3 and the printed matter 5 is printed.
a and 5b are obtained. On the other hand, the raster image data input by the print quality determination device 4 is subjected to arithmetic processing by a mask pattern generation unit (not shown) of the print quality determination device 4 to generate mask pattern data. An image pickup camera 6 and a position detection sensor 7 are connected to the print quality determination device 4. In response to a command from an image capturing unit (not shown) of the print quality determining device 4, the image capturing camera 6 captures an image of the printed surface of the printed material based on the raster image data, and outputs an image capturing signal to the print quality determining device 4. The image pickup unit of the print quality determination device 4 performs processing such as A / D conversion on the input image pickup signal to obtain detected image data.

The printed matters 5a and 5b are discharged from the printer 3 and transferred, and the image pickup of the printing surface by the image pickup camera 6 detects the printed matter 5 detected by the position detection sensor 7.
This is performed based on the position data of a and 5b. That is,
The image pickup unit of the print quality determination device 4 inputs the output signal of the position detection sensor 7 to calculate the position data of the printed matter 5a and 5b, and picks up a predetermined area of the printed matter 5a and 5b based on the position data. Then, the imaging camera 6 is instructed to perform imaging. Comparison determination unit (not shown) of the print quality determination device 4
Determines the quality of the print surface of the printed matter 5a, 5b by the printer 3 from the above-mentioned mask pattern data and the detected image data, and outputs the inspection result.

[0015]

EXAMPLES Next, the present invention will be described in detail based on examples. FIG. 2 is a diagram showing an example of print image data, mask pattern data, and detection image data. In FIG. 2, 21 is print image data,
22 is mask pattern data outside the inspection area, 23 is expansion pattern data, and 24 is detection image data. FIG.
In the above, the mask pattern data is expanded mask pattern data, and the expanded mask pattern data is composed of a portion of the out-of-inspection mask pattern data 22 and a portion of the expanded pattern data 23.

As shown in FIG. 2, the print image data 21 is larger in size than the detected image data 24. Both the print image data 21 and the detection image data 24 are bitmap data composed of light and dark data of a plurality of pixels arranged vertically and horizontally. The large size means that the image size is large when the number of pixels is large and the pixel array density is the same. In the case of FIG. 2, the size of the print image data 21 having a large size is changed to make print image data of the same size as the detected image data 24, and then mask pattern data is generated based on the data. This processing of making the sizes the same is performed by the vertical / horizontal magnification conversion means of the mask pattern generation unit. The process of converting the vertical / horizontal ratio performed by the vertical / horizontal ratio converting means is a process of making the number of pixels the same so that the print image and the detected image overlap. As such a data conversion method, a known method such as a nearest neighbor method, a bilinear method, or a cubic convolution method can be applied.

Further, as described above, the mask pattern data is composed of two portions, that is, the mask pattern data outside the inspection area 22 and the expansion pattern data 23. The expansion pattern data 23 is generated by binarizing the print data portion of the above-described print image data of the same size and then performing expansion processing. The process of generating the mask pattern data is performed by the binarizing unit, the expansion processing unit, and the mask processing unit of the mask pattern generation unit. With this mask pattern data (expanded mask pattern data), it is possible to mask the outside of the inspection area and the portion where the printing ink adheres. That is, it is possible to extract a portion in the inspection area where the printing ink does not adhere. Defects such as ink dripping and stains can be detected from the extracted data.

Another example different from that of FIG. 2 will be shown below. FIG. 3 is a diagram showing another example of print image data, mask pattern data, and detection image data. In FIG. 3, 31 is print image data, 32 is mask pattern data outside inspection area, 33 is reverse pattern data, 3
Reference numeral 4 is detection image data. In FIG. 3, the mask pattern data is contraction mask pattern data, and the contraction mask pattern data is composed of a portion of the mask pattern data outside the inspection area 32 and a portion of the inversion pattern data 33.

As shown in FIG. 3, the print image data 31 is larger in size than the detection image data 34. Although the same description as in the case of FIG. 2 is repeated, both the print image data 31 and the detection image data 34 are bitmap data composed of light and dark data of a plurality of pixels arranged vertically and horizontally. The large size means that
This means that if the number of pixels is large and the pixel array density is the same, the image size is large. In the case of FIG. 3, after changing the size of the print image data 31 having a large size to make the print image data of the same size as the detection image data 34, the mask pattern data is generated based on the data. This processing of making the sizes the same is performed by the vertical / horizontal magnification conversion means of the mask pattern generation unit.
The process of converting the vertical / horizontal ratio performed by the vertical / horizontal ratio converting means is a process of making the number of pixels the same so that the print image and the detected image overlap. As such a data conversion method, a known method such as a nearest neighbor method, a bilinear method, or a cubic convolution method can be applied.

Further, as described above, the mask pattern data is composed of two parts, that is, the mask pattern data outside the inspection area 32 and the reverse pattern data 33. The inversion pattern data 33 is generated by binarizing the print data portion of the above-described print image data of the same size, then performing contraction processing, and further performing inversion processing. The process of generating this mask pattern data is performed by the mask pattern generator 2
This is performed by the value conversion means, the contraction processing means, the inversion processing means, and the mask processing means. With this mask pattern data (contraction mask pattern data), it is possible to mask the outside of the inspection area and the portion to which the printing ink does not adhere. That is, it is possible to extract the portion of the inspection area to which the printing ink is attached. From the extracted data, it is possible to detect defects such as missing characters and blank areas.

Next, the entire data processing process in the print quality judging apparatus of the present invention including the above-mentioned processing will be described. FIG. 4 is a flow chart showing a data processing process in the print quality judging device and the peripheral device of the present invention. FIG.
First, the processing on the printing machine side will be described. The print data (see FIG. 1) is output to a RIP (raster image processor) (S1), and the RIP inputs the print data to generate raster image data (print image data is also referred to as raster image data) to generate a printer. The data is output to the inspection device (the print quality determination device is also referred to as an inspection device) (S2). The printer inputs the raster image data, prints the printed matter, and discharges the printed matter (S3). The printed matter is transported and approaches the image pickup area of the image pickup camera (S4).

The image pickup camera periodically and repeatedly picks up an image, and the image pickup signal is A / D converted, digitized, and repeatedly updated and stored in the buffer memory (S5). The position of the printed material to be transferred is detected by the position detection sensor. When the position of the printed material to be transferred reaches a predetermined position in the imaging area of the imaging camera, the position detection sensor transfers C.
The UE signal is output to the buffer memory (S6). Upon inputting the transfer CUE signal, the buffer memory transfers the stored detection image data to the comparison / determination unit of the inspection device (S7).

On the other hand, the raster image data output to the inspection device is stored in the storage device. The inspection apparatus can be realized by the body of a computer such as a personal computer or a workstation, or by adding a high-speed image processing apparatus to it if necessary. The raster image data is stored in the main memory, frame memory, image memory or the like of such a device (S8).

Next, in order to make the size of the raster image data coincide with the size of the detected image data, vertical and horizontal magnification conversion processing is performed. Normally, since the size of raster image data is larger than the size of the detected image data, the process of reducing the size of the raster image data is performed, but generally, either the raster image data or the detected image data may be subjected to the vertical / horizontal magnification conversion process. . It is assumed that the pixel size of the raster image data is A rows × B columns, and the pixel size of the detection image data obtained by imaging the print surface printed with the data is C rows × D columns. In that case, C / A =
If α and D / B = β, α and β are obtained in advance,
The raster image data is subjected to vertical-horizontal scaling conversion processing to a pixel size of (α × A) rows × (β × B) columns. As a method of the vertical-horizontal magnification conversion processing, as described above, a method such as the nearest neighbor method, the bilinear method, the cubic convolution method or the like can be applied (S9).

Next, the raster image data subjected to the vertical / horizontal magnification conversion processing is binarized to obtain binarized pattern data. The binarization method is a fixed threshold method in which a threshold value is given in advance, a p-tile method in which the brightness at which the cumulative distribution is p percent is used as a threshold value, and the brightness of the valley if the brightness histogram is bimodal. It is possible to apply a method such as a modal method in which the threshold value is the height value (S10).

On the other hand, inspection condition setting processing has been performed in advance (described later), and setting data such as the inspection area, vertical and horizontal magnification, and expansion / contraction processing conditions have been obtained (S1).
1). Next, based on this setting data, expansion processing is performed on the binarized pattern data to obtain expansion pattern data. If the binarized pattern data is used as it is for the expansion process, it is possible to prevent a difference from occurring due to an error in the vertical / horizontal magnification conversion processing when the resolution is different from the detected image data, a slight change in the lens magnification of the imaging camera, or distortion. Is done to In one expansion process, the pixel of “0” which is in contact with the pixel of “1” of the binary pattern data is set to the pixel of “1” by 1
It is a process of replacing only once. This expansion process is performed a predetermined number of times based on the setting data (S12).

Next, as shown in FIG. 2, the expansion pattern data 23 is assigned to the mask pattern data (S13). Further, the mask pattern data 22 outside the inspection area is allocated to the mask pattern data based on the setting data of the inspection area, and the mask pattern data (expanded mask pattern data) is generated (S14).

The detected image data transferred to the comparison / determination unit of the inspection device in S7 is masked based on the mask pattern data, and only the inspection area data is obtained. Mask processing is “1” of mask pattern data
The value of the pixel of the detected image data at the same position as the pixel of “0” is set to “0”, and the mask processing is the processing of leaving the value of the pixel of the detected image data at the same position as the pixel of “0” of the mask pattern data as it is. is there. Based on the data of only the inspection area masked in this way, the sum total of the pixel values is obtained by the sum calculation means of the comparison / determination unit. If the inspection area is normal, printing is not performed, so if it is normal, the sum of the pixel values becomes a small value (S15).

Next, the total sum is compared with a predetermined judgment reference value by the comparing means of the comparison judgment unit, and if the total sum is larger than the predetermined judgment reference value, an excessive failure signal is output.
The excessive defect signal is output when there is an abnormality such as printing or stain in the inspection area where printing should not be performed (S16).

The print quality determination process based on the mask pattern data (contraction process mask pattern data) by the contraction process is performed on the mask pattern data by the expansion process. Next, it will be described. The inspection condition setting process is performed in advance (described later), and the setting data such as the inspection area, the vertical / horizontal magnification, and the expansion / contraction process condition are obtained (S11).

On the basis of the setting data, the binarized pattern data is then subjected to shrinkage processing to obtain shrinkage pattern data. If the binarized pattern data is used as it is for the contraction process, it prevents generation of differences due to vertical / horizontal magnification conversion processing errors when the resolution differs from the detected image data, subtle changes in the lens magnification of the imaging camera, and distortion. Is done to One contraction process is a process of replacing the pixel of "1" in contact with the pixel of "0" of the binary pattern data with the pixel of "0" only once. This contraction processing is performed a predetermined number of times based on the setting data (S17).

Next, the contraction pattern data is subjected to the inversion process to obtain the inversion pattern data. The inversion process is a process of replacing the pixel of “0” with “1” and the pixel of “1” with “0”. As shown in FIG. 3, the reverse pattern data 33 is assigned to the mask pattern data (S1).
8). Further, the mask pattern data 32 outside the inspection area is allocated to the mask pattern data based on the setting data of the inspection area, and the mask pattern data (expanded mask pattern data) is generated (S19).

The detected image data transferred to the comparison / determination unit of the inspection device in S7 is masked based on the mask pattern data, and data of only the inspection area is obtained. Mask processing is “1” of mask pattern data
The value of the pixel of the detected image data at the same position as the pixel of “0” is set to “0”, and the mask processing is the processing of leaving the value of the pixel of the detected image data at the same position as the pixel of “0” of the mask pattern data as it is. is there. Based on the data of only the inspection area masked in this way, the sum of pixel omissions is calculated by the pixel omission sum total calculation means of the comparison / determination unit. If the inspection area is normal, printing is performed, so if it is normal, the total pixel omission has a small value (S20).

Next, the total sum is compared with a predetermined judgment reference value by the comparing means of the comparison judgment unit, and if the total sum is larger than the predetermined judgment reference value, an under-defective signal is output.
The under-defective signal is output when, for example, printing is not performed in the inspection area where printing should have been performed, or a character missing abnormality occurs (S21).

Next, the inspection condition setting process in S11 will be described. FIG. 5 is a flow chart showing the process of setting the inspection conditions. 6 is a diagram showing an example of a test pattern used in the inspection condition setting process. In the test pattern shown in FIG. 6, reference numeral 61 is a horizontal magnification confirmation mark, 62 is a center positioning mark, and 63 is a flow direction magnification confirmation mark. In FIG. 5, the description of the same parts as those of the process shown in FIG. 4 will be omitted or simplified.

A series of processing steps S101 to S in FIG.
Reference numeral 110 denotes the same processing step as S1 to S10 in FIG. However, the test pattern data shown in FIG. 6 is used as the print data. Therefore, the print image data, the binary print pattern data, the printed matter, the detection image data, etc. are based on the test pattern data shown in FIG. In the individual processing steps, S111 is S13, S112 is S14, and S1 is S1.
13 for S15, S117 for S18, S118 for S1
9, S119 is a processing step corresponding to S20.

First, setting of conditions for expansion processing will be described. The detected image data transferred to the comparison / determination unit of the inspection apparatus in S107 is masked based on the mask pattern data, and data of only the inspection area is obtained.
In the mask processing, the pixel value of the detected image data at the same position as the pixel of “1” of the mask pattern data is set to “0”,
The mask processing is processing in which the value of the pixel of the detected image data at the same position as the pixel of "0" of the mask pattern data is left as it is. Based on the data of only the inspection area masked in this way, the sum total of the pixel values is obtained by the sum calculation means of the comparison / determination unit. If the inspection area is normal, printing is not performed. Therefore, if the mask pattern data is obtained by using the expanded pattern data obtained by performing the necessary expansion processing on the binarized print pattern data, the total pixel value becomes a small value ( S113).

Next, the total sum is compared with a predetermined judgment reference value by the comparing means of the comparison / judgment unit, and if the sum is larger than the predetermined judgment reference value (S114), the current expansion pattern data ( In the case of the first time, the binary print pattern data is treated as the expansion pattern data), the expansion process is performed only once to generate new expansion pattern data, and the process returns to S111 to repeat the process. that time,
The cumulative total of expansion processes is stored. If the accumulated value exceeds the predetermined value, an error message is output and the operation is stopped (S115). The comparison means of the comparison / determination unit compares the total sum with a predetermined determination reference value, and when the total sum is smaller than the predetermined determination reference value (S114), the cumulative value of the expansion processing is set to the expansion processing value. Register as a set number of times (S
116).

Next, setting of conditions for contraction processing will be described. The detected image data transferred to the comparison / determination unit of the inspection apparatus in S107 is masked based on the mask pattern data, and data of only the inspection area is obtained.
In the mask processing, the pixel value of the detected image data at the same position as the pixel of “1” of the mask pattern data is set to “0”,
The mask processing is processing in which the value of the pixel of the detected image data at the same position as the pixel of "0" of the mask pattern data is left as it is. Based on the data of only the inspection area masked in this way, the sum of pixel omissions is calculated by the pixel omission sum total calculation means of the comparison / determination unit. If the inspection area is normal, printing is performed. Therefore, if the mask pattern data is obtained by using the reversal pattern data of the contraction pattern data obtained by performing the contraction process on the binarized print pattern data as much as necessary, the total pixel omission is small. Value (S11
9).

Next, the comparison means of the comparison / determination unit compares the total sum with a predetermined determination reference value, and if the total is larger than the predetermined determination reference value (S120), the current contraction pattern data ( In the case of the first time, the binarized print pattern data is treated as contraction pattern data), the contraction process is performed only once to generate new contraction pattern data, and the process returns to S117 to repeat the process. that time,
The cumulative total of contraction processing is stored. If the cumulative value exceeds the predetermined value, an error message is output and the operation is stopped (S121). The comparison means of the comparison / determination unit compares the total sum with a predetermined determination reference value, and if the total sum is smaller than the predetermined determination reference value (S114), the cumulative value of the contraction processing is set to the value of the contraction processing. Register as a set number of times (S
122).

[0041]

As described above, according to the present invention, the problems caused by human inspection, such as human burden, work load, and mixing of defective products into products, are eliminated, and printed images differ depending on individual printed matter. Also provided is a print quality determination device that can automatically perform an inspection. Further, according to the present invention having the aspect ratio conversion means in the mask pattern generation unit, when the vertical and horizontal arrangement densities of the pixels forming the print image data are different from the vertical and horizontal arrangement densities of the pixels forming the detected image data. Can also be inspected. Further, according to the present invention, the mask pattern generation unit includes the binarization unit, the expansion processing unit, and the mask processing unit.
With the expansion mask pattern data, it is possible to extract a portion in the inspection area where the printing ink does not adhere. Further, the mask pattern generation unit includes a binarization unit, a contraction processing unit,
According to the present invention having the reversal processing unit and the mask processing unit, the contraction mask pattern data can be used to extract the portion of the inspection region to which the printing ink is attached.

Further, according to the present invention, the comparison / determination unit has a sum calculation means for calculating the sum of the pixel values of the detected image data existing outside the mask area of the expanded mask pattern data, and the comparison means. When an abnormality occurs in printing, an excessively large failure signal is output. Further, according to the present invention, the comparison / determination unit includes a total sum calculation unit that calculates the sum of pixel values of the detected image data existing outside the mask area of the contraction mask pattern data, and a comparison unit.
If an abnormality occurs that there is a missing print outside the mask area, an undersize defect signal is output. Further, according to the present invention having the inspection condition setting unit, since the condition of the expansion process and the condition of the contraction process are set based on the test pattern in the installed state of the print quality determination device, proper setting can be easily performed. You can

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a print quality determination device of the present invention and its peripheral devices.

FIG. 2 is a diagram showing an example of print image data, mask pattern data, and detection image data.

FIG. 3 is a diagram showing another example of print image data, mask pattern data, and detection image data.

FIG. 4 is a flowchart showing a data processing process in the print quality determination device and the peripheral device of the present invention.

FIG. 5 is a flowchart showing a process of inspection condition setting processing.

[Explanation of symbols]

 1 Print Data 2 Rasula Image Processor (RIP) 3 Printer 4 Print Quality Judgment Device 5a, 5b Printed Material 6 Imaging Camera 7 Position Detection Sensor 8 Imaging Camera 21, 31 Print Image Data 22, 32 Out-of-Inspection Area Mask Pattern Data 23 Expansion Pattern Data 24, 34 Detection image data 33 Reverse pattern data 61 Horizontal direction magnification confirmation mark 62 Center positioning mark 63 Flow direction magnification confirmation mark

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[Procedure amendment]

[Submission date] February 22, 1996

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] Brief description of drawings

[Correction method] Added

[Correction contents]

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a print quality determination device of the present invention and its peripheral devices.

FIG. 2 is a diagram showing an example of print image data, mask pattern data, and detection image data.

FIG. 3 is a diagram showing another example of print image data, mask pattern data, and detection image data.

FIG. 4 is a flowchart showing a data processing process in the print quality determination device and the peripheral device of the present invention.

FIG. 5 is a flowchart showing a process of setting inspection conditions.

FIG. 6 is a diagram showing an example of a test pattern used in an inspection condition setting process.

[Explanation of Codes] 1 print data 2 Rasula image processor (RIP) 3 printer 4 print quality judgment device 5a, 5b printed matter 6 imaging camera 7 position detection sensor 8 imaging camera 21, 31 print image data 22, 32 mask pattern outside inspection area Data 23 Expansion pattern data 24, 34 Detection image data 33 Reverse pattern data 61 Horizontal direction magnification confirmation mark 62 Center positioning mark 63 Flow direction magnification confirmation mark

Claims (7)

[Claims] 1. A mask pattern generation unit for generating mask pattern data from print image data, an image pickup unit for picking up printed matter printed based on the print image data to obtain detection image data, the mask pattern data and the A print quality determination device comprising: a comparison / determination unit that determines the quality of a printed material from detected image data. 2. The mask pattern generation unit includes a vertical / horizontal magnification conversion unit, and the vertical / horizontal magnification conversion unit at least one of the print image data and the detection image data is arranged so that the print image and the detection image overlap each other. The print quality determination apparatus according to claim 1, wherein the magnification is converted. 3. The mask pattern generation unit includes a binarization unit, an expansion processing unit, and a mask processing unit, the binarization unit binarizes the print image data with a predetermined threshold, Binarized print pattern data is generated, the expansion processing unit performs expansion processing of the binarized print pattern data to generate expansion pattern data, and the mask processing unit is data for masking the outside of the inspection region. The print quality determination apparatus according to claim 1, wherein the mask pattern data outside a certain inspection area and the expansion pattern data are combined to generate expansion mask pattern data. 4. The mask pattern generation unit includes a binarization unit, a contraction processing unit, an inversion processing unit, and a mask processing unit, and the binarization unit sets the print image data to a predetermined threshold value. And binarize print pattern data to generate binarized print pattern data, the shrinking processing unit performs shrinkage processing on the binarized print pattern data to generate shrinkage pattern data, and the inversion processing unit creates the shrinkage pattern data. Inversion processing is performed to generate inversion pattern data, and the mask processing unit synthesizes the out-of-inspection-area mask pattern data, which is data for masking the outside of the inspection area, with the inversion pattern data to generate contraction mask pattern data. The print quality determination device according to claim 1, wherein the print quality determination device comprises: 5. The comparison / determination unit includes a sum total calculation unit and a comparison unit, and the sum total calculation unit includes a pixel value of the detected image data existing outside a mask area of the expanded mask pattern data. The print quality determination device according to claim 3, wherein the total sum is calculated, and the comparison unit compares the total sum with a predetermined value and outputs an excessive defect signal when the total sum is large. 6. The comparison / determination unit includes a pixel omission total sum calculation means and a comparison means, wherein the pixel omission total sum calculation means is present in the detected image data existing outside a mask area of the contraction mask pattern data. 5. The print quality judgment according to claim 4, wherein the total sum of the pixel omissions of the above is calculated, and the comparison means compares the total sum with a predetermined value and outputs an under-defective signal when the total sum is large. apparatus. 7. An inspection condition setting section for setting at least conditions for expansion processing by said expansion processing means and conditions for contraction processing by said contraction processing means based on a test pattern. The print quality determination device according to any one of 1 to 6.