JP2017173069A - Printed matter inspection device, printed matter inspection method and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printed matter inspection device that determines with higher precision that a pattern of a defect of printed matter is generated in printing control of a printing apparatus.SOLUTION: During comparison in inspection between a reference image used to inspect printed matter to be inspected and an inspection object image obtained by imaging the printed matter to be inspected, a correction parameter for correction such that the inspection object image matches the reference image is determined. A time series of storage patterns of correction parameters estimated to be determined in sequence for respective pieces of printed matter in a period in which abnormality occurs to the printed matter are acquired. A printing state pattern representing a time series of correction parameters determined each time printed matter is printed by a printing apparatus which prints the printed matter is compared with the storage patterns.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a printed matter inspection apparatus, a printed matter inspection method, and a program.

  An abnormality such as a printing deviation may occur periodically or continuously on a printed matter printed by the printing apparatus. As examples of the periodic abnormality and the continuous abnormality, there are “print density defect” and “print pattern omission” in addition to misalignment of the print pattern. Patent Document 1, Patent Document 2, and Patent Document 3 disclose techniques for inspecting such printed matter for defects.

JP-A-2015-178234 JP 2009-229555 A JP 2012-137482 A

  By the way, in the technique for inspecting the defect of the printed matter as described above, there is a demand for a technique for determining that a defective pattern of the printed matter is generated in the printing apparatus with higher accuracy.

  Therefore, an object of the present invention is to provide a printed matter inspection apparatus, a printed matter inspection method, and a program that can solve the above-described problems.

  According to the first aspect of the present invention, the printed matter inspection apparatus performs the comparison in the inspection between the reference image used for the inspection of the printed matter to be inspected and the inspection target image obtained by imaging the printed matter to be inspected. It is estimated that a correction parameter determining unit that determines a correction parameter to be corrected so that an inspection target image is suitable for comparison with the reference image, and sequentially determining each of the printed materials during a period in which an abnormality is expected to occur in the printed material. The correction parameter time-series first pattern, and the correction parameter time-series second pattern and the first pattern determined each time the printed matter is printed from a printing apparatus that prints the printed matter. A comparison unit for comparing the two.

  According to the second aspect of the present invention, the printed matter inspection method includes a reference image used for inspecting a printed matter to be inspected and an inspection target image obtained by imaging the printed matter to be inspected in the inspection. The correction parameter for correcting the inspection target image so as to be suitable for comparison with the reference image is determined, and the correction parameter is estimated to be sequentially determined for each of the printed materials in a period in which the printed material is expected to be abnormal. Are obtained, and the second pattern of the time series of the correction parameter determined each time the printed matter is printed from the printing apparatus that prints the printed matter is compared with the first pattern.

  According to a third aspect of the present invention, there is provided a program comprising: a reference image used for inspecting a printed matter to be inspected by a computer of a printed matter inspection apparatus; and the inspection target image obtained by imaging the printed matter to be inspected. Correction parameter determination means for determining a correction parameter for correcting the inspection target image so as to be suitable for comparison with the reference image at the time of comparison in inspection, and for each of the printed materials during a period in which an abnormality is expected to occur in the printed material Whenever the first pattern is read from the correction parameter time-series pattern storage unit that stores the first pattern of the time-series correction parameters estimated to be sequentially determined, the printed material is printed from the printing apparatus that prints the printed material. Comparison means for comparing the determined second time-series pattern of the correction parameter with the first pattern, To function.

  According to the present invention, it is possible to determine a defect of a printed matter with higher accuracy.

It is a figure which shows the relationship between a printed matter inspection apparatus and a printing apparatus. It is a figure which shows the hardware constitutions of a printed matter inspection apparatus. It is a functional block diagram which shows the structure of a printed matter inspection apparatus. It is a 1st figure explaining the memory pattern of a correction parameter. It is a 2nd figure explaining the memory pattern of a correction parameter. It is a figure which shows the processing flow of a printed matter inspection apparatus. It is a 3rd figure explaining the memory | storage pattern of a correction parameter. It is a 4th figure explaining the memory pattern of a correction parameter. It is a figure which shows the minimum structure of a printed matter inspection apparatus.

Hereinafter, a printed matter inspection apparatus according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram illustrating a relationship between a printed matter inspection apparatus and a printing apparatus according to the present embodiment.
The printed matter inspection apparatus 1 is communicatively connected to the printing apparatus 2. The printing apparatus 2 may be provided with an image reading apparatus that captures an image of a printed matter after printing. The image reading apparatus outputs to the printed matter inspection apparatus 1 data of an inspection target image obtained by picking up an optically picked up printed matter.

FIG. 2 is a diagram illustrating a hardware configuration of the printed matter inspection apparatus.
As shown in FIG. 2, the printed matter inspection apparatus 1 includes a CPU (Central Processing Unit) 101, an IF (Interface) 102, a communication module 103, a ROM (Read Only Memory) 104, a RAM (Random Access Memory) 105, an HDD (Hard). Disk Drive) 106 or the like.

FIG. 3 is a functional block diagram showing the configuration of the printed matter inspection apparatus according to the embodiment.
The printed matter inspection apparatus 1 executes a program stored in advance by the CPU 101, whereby an image acquisition unit 11, a correction parameter determination unit 12, a parameter comparison unit 13, an inspection device control unit 14 (stop control unit), and a printing device control unit 15. Each function of the correction unit 16 and the image comparison unit 17 is provided. Further, the printed matter inspection apparatus 1 includes a storage unit 18.
The image acquisition unit 11 acquires image data (inspection target image) of a printed matter to be inspected sequentially printed by the printing apparatus 2 from an image reading apparatus provided in the printing apparatus 2.
The printed matter inspection apparatus 1 compares the reference image used for the printed matter inspection with the inspection target image obtained by imaging the printed matter to be inspected, and inspects the printed matter. The correction parameter determination unit 12 determines a correction parameter for correcting the inspection target image to be suitable for comparison with the reference image when comparing the reference image and the inspection target image in this inspection. A correction parameter suitable for comparison is, for example, a parameter for correcting distortion, color density, and printing position of an inspection target image.
The storage unit 18 stores a storage pattern (first pattern) indicating a time-series pattern of correction parameters estimated to be sequentially determined for each of the printed materials during a period in which the printed material is expected to be abnormal.
The parameter comparison unit 13 compares the time-series print status pattern (second pattern) of the correction parameters determined each time printing is performed from the printing apparatus with the storage pattern.

The inspection device control unit 14 controls the operation of the printed matter inspection device 1.
The printing device control unit 15 controls the operation of the printing device 2.
The correction unit 16 corrects the inspection target image based on the correction parameter determined by the correction parameter determination unit 12.
The image comparison unit 17 compares the reference image with the inspection target image.

  The printed matter inspection apparatus 1 compares the inspection target image obtained from the printing device 2 with the reference image, and determines whether the printed matter is normally printed. The printed matter inspection apparatus 1 sequentially inputs inspection target images obtained by imaging all printed matters printed by the printing apparatus 2 and compares them with reference images. When comparing the inspection target image and the reference image, the printed matter inspection apparatus 1 compares the inspection target image after correcting distortion, color density, position, and the like. Such correction enables appropriate comparison with the reference image. The printed matter inspection apparatus 1 compares the image to be inspected with respect to the printed matter, which is determined to be damaged paper, with the possibility of the loss, by applying a correction parameter of high intensity (value) and the reference image. When the inspection target image is compared with the reference image, and it is determined by a predetermined algorithm that the inspection target image does not match the reference image, the printed matter corresponding to the inspection target image is determined to be waste paper. can do. In general, the image to be inspected, which has become a waste paper, has a large difference from the reference image, so that the amount to be corrected before the comparison increases, and the strength (value) of the correction parameter also increases.

FIG. 4 is a first diagram for explaining a correction parameter storage pattern.
In the present embodiment, the correction parameter storage pattern is a diagram illustrating a correspondence relationship between the number of inspections, which is a count value of printed materials sequentially printed by the printing apparatus 2, and the correction parameter intensity. In FIG. 4, the storage pattern of the correction parameters is shown in FIG. The upper diagram (b) of FIG. 4 shows the number of inspections, which is the count value of the printed matter sequentially printed by the printing apparatus 2 that generates the damaged paper in a predetermined pattern, and the output when the damaged paper is generated by the printing apparatus 2. It is a figure of the loss paper generation | occurrence | production pattern which shows the relationship of the made waste paper signal. When the damaged paper generation pattern is a pattern as shown in FIG. 4B, the printed matter inspection apparatus 1 that determines the correction parameters for the inspection target image of the printed matter printed by the printing apparatus 2 is shown in FIG. The intensity of the correction parameter indicated by the correction parameter storage pattern as shown is determined.
Here, the printed matter inspection apparatus 1 may store a plurality of correction parameter storage patterns. For example, the printed matter inspection apparatus 1 may store a plurality of correction parameter storage patterns for an abnormal pattern to be detected. In this case, if the abnormal pattern matches any of the plurality of storage patterns, it can be detected that a predetermined abnormal pattern has occurred in the printing apparatus 2.

  In the present embodiment, the printed matter inspection apparatus 1 stores a storage pattern of correction parameters as shown in FIG. The storage pattern of the correction parameter may be created by an administrator who has confirmed the loss paper generation pattern of the printing apparatus 2 in advance. Alternatively, the storage pattern of the correction parameter may be the one that stores the relationship between the correction parameter intensity detected by the printed matter inspection apparatus 1 in the past and the number of inspections of the printed matter based on the acquisition of the inspection target image from the printing device 2. Good.

  The printed matter inspection apparatus 1 determines whether or not the correction parameter pattern (printing status pattern) sequentially obtained by the current printing by the printing apparatus 2 matches the storage pattern stored in advance. When the print status pattern matches the storage pattern, the printed matter inspection apparatus 1 can specify that an abnormal event of the printing apparatus 2 that has been assumed in advance has occurred. In the printing apparatus, there may be a situation where a state where the intensity of the correction parameter is high as shown in FIG. For example, such a situation may occur due to mechanical factors. Note that the printed matter inspection apparatus 1 according to the present embodiment is not limited to the one that detects a situation in which a high correction parameter strength state as illustrated in FIG.

FIG. 5 is a second diagram for explaining a correction parameter storage pattern.
In the lost paper occurrence pattern shown in FIG. 5B, the lost paper is generated on the 6th sheet from the start of the counting of the number of inspections, the generation of the lost paper is continued up to the 15th sheet, and no lost paper is generated on the 16th sheet. Suppose that the lossy paper is continuously generated from the 17th sheet to the 22nd sheet.
On the other hand, the loss paper generation pattern shown in FIG. 4B is a pattern in the case where the generation of the loss paper signal continues from the sixth sheet to the twenty-second sheet.
4B is recorded in the printed matter inspection apparatus 1 as a predetermined pattern, and the loss occurrence pattern as shown in FIG. Assume that the occurrence of an abnormality in the printing apparatus is determined based on the occurrence pattern. In this case, the pattern shown in FIG. 4B and the pattern shown in FIG. 5B are completely inconsistent in the state of occurrence of the waste paper on the 16th sheet. Even if this is done, it is not regarded as abnormal just by storing the lost paper occurrence pattern as shown in FIG.
However, when it is determined that the paper is not damaged on the 16th sheet in FIG. 5B, it is determined that the paper is normal due to the recognition error of the printed matter inspection apparatus 1, or it is determined that the paper is normal without being determined to be slightly damaged. If it has been determined, the printed matter inspection apparatus 1 may determine that there is no abnormality even though the abnormality originally occurs regularly in the printing apparatus 2.
In other words, when the pattern is a digital pattern showing a discrete binary value of 0 or 1, such as a waste paper generation pattern, even if it is determined that an abnormal pattern has occurred, it is determined that the pattern is not abnormal. There was a possibility of being done.
In the present invention, the storage pattern of the correction parameter as shown in FIG. 5A is an analog pattern that is the relationship between the intensity of the correction parameter and the number of inspections. Therefore, even if a pattern abnormality as shown in FIG. 5B occurs in the printing apparatus 2, the strength of the correction parameter obtained from the inspection target image of the 16th printed matter after counting is indicated by the storage pattern. If it is close to the strength value of the 16th correction parameter to be printed, it is determined that the print pattern obtained by the situation of the storage pattern (FIG. 5A) and FIG. It can be determined that an abnormality has occurred in the device 2.

FIG. 6 is a diagram showing a processing flow of the printed matter inspection apparatus according to the present embodiment.
Next, the processing flow of the printed matter inspection apparatus according to the present embodiment will be described in order.
First, an image reading apparatus provided in the printing apparatus 2 captures an image of a printed matter printed by the printing apparatus 2 and sequentially outputs the data to the printed matter inspection apparatus 1. The printed image is hereinafter referred to as an inspection target image. In the printed matter inspection apparatus 1, the image acquisition unit 11 acquires an inspection target image (step S11). Then, the correction parameter determination unit 12 determines a correction parameter based on the inspection target image (step S12). This correction parameter is a parameter for correcting the inspection target image so as to be suitable for comparison with the reference image, and is a parameter for correcting the distortion, color density, and printing position of the inspection target image. Any method may be used for determining the correction parameter, and a known technique may be used. More specifically, the correction parameter may be a horizontal movement amount value, a vertical movement amount value, a color 1 print density correction value, a color 2 print density correction value, or the like.

  The image acquisition unit 11 determines whether there is a next inspection target image (step S13), and repeats the process of step S11. Each correction parameter is determined for the inspection target image of a predetermined number of printed matter continuously printed by the processing of step S11 and step S12. The correction parameter determination unit 12 generates a printing status pattern in which the correction parameters for the inspection target images of the predetermined number of printed materials are represented in the determined order (step S14). This print status pattern is generated every time one image to be inspected is input.

  The parameter comparison unit 13 reads a storage pattern recorded in advance in the storage unit 18 for correction parameters. Further, the printing status pattern is acquired from the correction parameter determination unit 12. The parameter comparison unit 13 compares the storage pattern and the printing status turn to determine whether they are similar (step S15). If the parameter comparison unit 13 determines that the storage pattern and the printing status pattern are similar, it determines that a desired abnormality has occurred in the printing apparatus. The parameter comparison unit 13 instructs the inspection device control unit 14 to stop the printed matter inspection device 1 when the storage pattern and the print status pattern are similar. Then, when the inspection apparatus control unit 14 obtains a stop instruction, the inspection apparatus control unit 14 stops the operation of the printed matter inspection apparatus 1 (step S16). Alternatively, the parameter comparison unit 13 may instruct the printing apparatus control unit 15 to stop the printing apparatus 2 when the storage pattern and the printing status pattern are similar.

  If the storage pattern and the printing status pattern are not similar, the parameter comparison unit 13 instructs the correction unit 16 to correct the inspection target image for which each correction pattern indicated by the printing status pattern has been determined. The correction unit 16 sequentially applies the correction parameter determined in step S12 to the image to be inspected in which each correction pattern indicated by the printing status pattern is determined, and corrects the image (step S17). The correction unit 16 outputs the corrected inspection target image corrected by the correction parameter to the image comparison unit 17. The image comparison unit 17 compares the acquired corrected inspection target image with the reference image. The image comparison unit 17 determines whether there is no problem in quality as a result of the comparison between the inspection target image and the reference image (step S18). This quality determination is made based on whether or not the value indicating the degree of similarity when the corrected inspection target image and the reference image are compared is within an allowable value. For example, the similarity may be a value that determines that there is no problem in quality if it is within an allowable value, and that determines that there is a problem in quality if it exceeds the allowable value.

  The image comparison unit 17 sequentially outputs a determination result including a quality ID indicating whether there is no problem in quality and an image ID of the inspection target image to the printing apparatus control unit 15 for each inspection target image. The printing apparatus control unit 15 converts the image ID included in the determination result into an ID of a printed material corresponding to the inspection target image indicated by the image ID. Note that the correspondence between the IDs of the printed matter and the inspection target image may be acquired by the image acquisition unit 11 from the printing apparatus 2 and recorded in the storage unit 18 in advance. The printing apparatus control unit 15 outputs an inspection result indicating the correspondence relationship between the quality ID and the printed matter ID to the printing apparatus 2 (step S19). The printing apparatus 2 sorts the printed material into regular paper and damaged paper based on the inspection result. Specifically, when the quality ID is an ID indicating that there is a problem with the quality, the printing apparatus 2 distributes the printed material indicated by the ID of the printed material included in the inspection result to the distribution destination of the waste paper. On the other hand, when the quality ID is an ID indicating that there is no problem in quality, the printing apparatus 2 distributes the printed material indicated by the ID of the printed material included in the inspection result to the distribution destination of the regular paper.

  As described above, the embodiments of the present invention have been described. However, according to the above-described processing, it is more accurately determined that the printing state indicated by the storage pattern recorded in the printed matter inspection apparatus 1 has occurred in the printing apparatus 2. be able to.

The printed matter inspection apparatus 1 may have the following two forms.
(1) Printing device add-on type The printing device add-on type adds the configuration of the printed matter inspection device 1 to the inside of the printing device as a retrofit. After printing a pattern or the like on the printing paper, the printing apparatus 2 discharges the paper to a discharge destination. There are a plurality of discharge destinations, which can be switched by an external signal from the printed matter inspection apparatus 1. During the operation from printing to discharging of the printing apparatus 2, the printed matter inspection apparatus 1 acquires image data from a camera or the like installed in the printing apparatus 2, compares it with a reference image, and notifies the determination result to the printing apparatus 2. To do. First, the operation of the printing apparatus 2 exists, and the printed matter inspection apparatus 1 performs the above-described processing so as to make a judgment on whether the damage is in time or not within the time limit from printing to discharge. In this case, printing and inspection can be combined into one process. Further, since there is one process, it is possible to shorten the time until the abnormality of the printing apparatus 2 detected by the printed matter inspection apparatus 1 is fed back to the printing apparatus 2.

(2) Stand-alone type The stand-alone type indicates a state in which the printing apparatus 2 and the printed matter inspection apparatus 1 are independent from each other. In this case, the process in each apparatus is separated from the printing process and the inspection process. Since the printing apparatus 2 and the printed matter inspection apparatus 1 can be designed independently, the development of the apparatus can be performed flexibly, but there are two printing and inspection processes. In this case, since there are two processes, it takes time to feed back the abnormality of the printing apparatus 2 detected by the printed matter inspection apparatus 1 to the printing apparatus 2.

FIG. 7 is a third diagram for explaining a correction parameter storage pattern.
FIG. 8 is a fourth diagram for explaining a correction parameter storage pattern.
In the case where the storage pattern of the correction parameter stored in advance is the storage pattern A indicated by a solid line, as shown in FIG. It can be detected by the memory pattern A. On the other hand, in the situation where the waste paper is periodically generated with a short cycle as shown in FIG. 7B, when the abnormality of the eighth sheet as shown in FIG. An abnormality cannot be detected by A. However, an abnormality as shown in FIG. 8B may be detected using both the memory pattern A and the memory pattern B indicated by a broken line.

FIG. 9 is a diagram showing a minimum configuration of the printed matter inspection apparatus.
The printed matter inspection apparatus 1 may include at least the correction parameter determination unit 12 and the parameter comparison unit 13.

  The printed matter inspection apparatus 1 and the printing apparatus 2 described above have a computer system inside. Each process described above is stored in a computer-readable recording medium in the form of a program, and the above process is performed by the computer reading and executing the program. Here, the computer-readable recording medium means a magnetic disk, a magneto-optical disk, a CD-ROM, a DVD-ROM, a semiconductor memory, or the like. Alternatively, the computer program may be distributed to the computer via a communication line, and the computer that has received the distribution may execute the program.

  The program may be for realizing a part of the functions described above. Furthermore, what can implement | achieve the function mentioned above in combination with the program already recorded on the computer system, and what is called a difference file (difference program) may be sufficient.

DESCRIPTION OF SYMBOLS 1 ... Print inspection apparatus 2 ... Printing apparatus 11 ... Image acquisition part 12 ... Correction parameter determination part 13 ... Parameter comparison part 14 ... Inspection apparatus control part 15 ... Printing apparatus control Unit 16 ... Correction unit 17 ... Image comparison unit 18 ... Storage unit

Claims (6)

Correction for correcting the inspection target image to be suitable for comparison with the reference image at the time of comparison between the reference image used for the inspection of the printed material to be inspected and the inspection target image obtained by imaging the printed material to be inspected A correction parameter determination unit for determining parameters;
From the printing device that obtains a first pattern of the time series of the correction parameters estimated to be sequentially determined for each of the printed materials in a period in which an abnormality is expected to occur in the printed material, and the printed material prints the printed material A comparison unit that compares the first pattern with the second pattern of the time series of the correction parameter determined each time the printing is performed;
A printed matter inspection apparatus comprising: A stop control unit for stopping the printing apparatus when the first pattern and the second pattern are similar;
A printed matter inspection apparatus according to claim 1. Storing a plurality of the first patterns having different time-series patterns of the correction parameters;
The printed matter inspection apparatus according to claim 2, wherein the comparison unit compares a composite pattern of the plurality of first patterns with the second pattern. The printed matter inspection apparatus according to claim 3, wherein the stop control unit stops the printing apparatus when the composite pattern and the second pattern are similar. Correction for correcting the inspection target image to be suitable for comparison with the reference image at the time of comparison between the reference image used for the inspection of the printed material to be inspected and the inspection target image obtained by imaging the printed material to be inspected Determine the parameters,
From the printing device that obtains a first pattern of the time series of the correction parameters estimated to be sequentially determined for each of the printed materials in a period in which an abnormality is expected to occur in the printed material, and the printed material prints the printed material A printed matter inspection method of comparing the first pattern with the second pattern in time series of the correction parameters determined each time printing is performed. The computer of the printed matter inspection device,
Correction for correcting the inspection target image to be suitable for comparison with the reference image at the time of comparison between the reference image used for the inspection of the printed material to be inspected and the inspection target image obtained by imaging the printed material to be inspected Correction parameter determining means for determining a parameter;
The first pattern from the correction parameter time-series pattern storage unit that stores the time-series first pattern of the correction parameters estimated to be sequentially determined for each of the printed materials during a period in which an abnormality is expected to occur in the printed material. Comparing means for comparing the first pattern with the second pattern in time series of the correction parameter determined each time the printed matter is printed from a printing apparatus that prints the printed matter,
Program to function as.

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