The entire disclosure of Japanese patent Application No. 2018-199017, filed on Oct. 23, 2018, is incorporated herein by reference in its entirety.
The present invention relates to an image inspection apparatus and an image inspection program for inspecting an abnormality of printed matter by comparing an image to an image obtained by reading a printed image.
Paper printed by an image forming apparatus may have an abnormality such as a stain and a scratch of an image due to various reasons.
In order to detect the abnormality, there is a technique for detecting an abnormality by reading paper immediately after being printed with, for example, a scanner. In the technology, first, the first image is printed and scanned to be registered as an answer image. The answer image is compared with the scanning result of an image subsequently printed out. An abnormality is thereby detected.
In recent years, there has been a technique called variable printing. In the variable printing, images different from record by record are generated in accordance with a record value recorded in a database. In recent formats for variable printing, such as PPML and PDF/VT, information on reusability is embedded for each object. A reusable object can make processing time more efficient than a traditional print image format by temporarily storing data after raster image processing (RIP) and reusing the data after the RIP each time the reusable object is drawn after the storage. Inspection of an abnormality of printed matter is required also in such variable printing.
In variable printing, however, a part of an image is different paper by paper. As a result, the comparison to the answer image obtained by scanning the first output image cannot be performed, and image abnormality detecting processing cannot be performed.
In contrast, in JP 2014-146253 A, inspection processing is performed by detecting a reusable object in variable printing, recording an image after RIP as an answer image, and comparing the answer image to RIP result of a reusable object to be used.
In addition, in JP 2012-000876 A, an answer image is generated from information on a reusable (fixed) object and a variable object. The reusable object is treated as a fixed object always arranged in the same place. When the reusable object is arranged in various places page by page, the reusable object is treated as a variable object.
Unfortunately, JP 2014-146253 A discloses just a means for determining whether an RIP result is correct for each reusable object, and does not disclose a configuration for creating an answer image based on information on the arrangement position of the reusable object. Even when there is an abnormality in the subsequent printing processing, the abnormality can thus not be detected.
In JP 2012-000876 A, a variable object region is subject to inspection processing different from that for a fixed object region. Since the inspection accuracy for the variable object region is generally lower than that for the fixed object, the accuracy in the entire output job is lowered.
The invention has been made in the context of the above-described circumstances, and an object thereof is to achieve image inspection of a variable print job with high accuracy.
To achieve the abovementioned object, according to an aspect of the present invention, an image inspection apparatus reflecting one aspect of the present invention comprises a hardware processor that inspects an abnormality of printed matter by comparing a preliminarily prepared answer image with an image obtained by reading a printed image, wherein the hardware processor generates a plurality of answer images based on a combination of pieces of arrangement information on a reusable object and a variable unique object in variable printing.
The advantages and features provided by one or more embodiments of the invention will become more fully understood from the detailed description given hereinbelow and the appended drawings which are given by way of illustration only, and thus are not intended as a definition of the limits of the present invention:
Hereinafter, one or more embodiments of the present invention will be described with reference to the drawings. However, the scope of the invention is not limited to the disclosed embodiments.
Although a communication network such as a local area network (LAN) and a wide area network (WAN) can be used as the communication line 30, contents of the communication line in the invention are not particularly limited and the communication line 30 may include a serial cable.
The image forming apparatus 10 includes an image forming unit 150 and an image inspection apparatus 20. The image forming unit 150 prints an image on paper. The image inspection apparatus 20 includes an output object reader 190, and is incorporated downstream of the image forming unit 150. The image inspection apparatus 20 detects an abnormality by scanning an image printed on a recording medium and comparing the scanned image to an answer image.
It should be noted that, in the above-described embodiment, the image inspection apparatus 20 is described as including the output object reader 190, but the image inspection apparatus may acquire a reading result from the output object reader without the output object reader in the image inspection apparatus.
In the above-described embodiment, the image forming apparatus 10 is described as including the image inspection apparatus 20, but the image inspection apparatus may be equipped regardless of the image forming apparatus. The image inspection apparatus may be equipped as an external apparatus, or equipped in, for example, the client terminal or a server. In short, the image inspection apparatus is only required to get a reading result of printed paper and compare the reading result to an answer image. The installation location is not particularly limited.
Control blocks of the image forming apparatus 10 will now be described with reference to
The image forming apparatus 10 includes a controller 100, a communication unit 102, a print controller 103, a storage 104, an operation display 105, an image formation conveyor 107, a sensor 109, a document reader 110, an RIP processor 120, a data storage 130, an image processor 140, an image forming unit 150, a fixing unit 160, and an output object reader 190.
The controller 100 controls each component in the image forming apparatus 10.
The controller 100 can include a central processing unit (CPU), a memory such as a read only memory (ROM) and a random access memory (RAM), a hard disk drive (HDD). The controller 100 decompresses a program stored in the ROM or the HDD in the RAM, and executes the program with the CPU. The HDD may also store, for example, layout data, which specifies the arrangement of objects in variable printing, and image data before rasterization.
In the controller 100, a program is executed. An image inspection program of the invention is operated in part of the controller 100. A read image can be inspected for abnormality. Consequently, in the embodiment, the controller 100 functions as an image inspection controller of the invention. It should be noted that, although, in the embodiment, the function of the image inspection controller is described as being executed by the controller 100 that controls the entire image forming apparatus, an image inspection controller may be prepared as being different from the controller that controls tire image forming apparatus, may be provided in the image inspection apparatus to be used only for image inspection, and may be provided in, for example, the client terminal or the server.
The communication unit 102 communicates with another set apparatus (e.g., external device). The print controller 103 receives job data written in a page description language from the external device, and stores the received job data as necessary.
The storage 104 stores, for example, various settings and programs.
The operation display 105 receives an operation input from a user, and displays the status of the image forming apparatus 10.
The image formation conveyor 107 conveys paper in the apparatus. The sensor 109 detects various states of the paper regarding image formation and paper conveyance. The document reader 110 reads an image of a document with an imaging device to generate document image data.
The RIP processor 120 executes RIP processing on job data before RIP processing. The job data has been received by the print controller 103, and is written in the page description language. The RIP processor 120 converts the job data into image data in a bitmap format. An image can be formed with the image data.
The data storage 130 stores image data for image formation and various pieces of data. It should, be noted that the data storage 130 includes an image memory for reading and an image memory for printing. The image memory for reading receives image data. The image memory for printing outputs the received image data for image formation. Information on, for example, reusable objects and variable unique objects in variable printing may be stored in the image memory for reading. An answer image used for comparison in image inspection can also be stored in the data storage 130.
The image processor 140 executes various types of image processing necessary for image formation. The image forming unit 150 forms an image on paper based on an image formation command and image data stored in the image memory for printing in the data storage 130.
The fixing unit 160 stabilizes the image, which has been formed on the paper with toner, by heat and pressure.
The output object reader 190 reads the image on the paper, and generates read image data.
Although the image forming unit 150 may form an image in a plurality of colors, this is not limitative, and the image forming unit 150 may form a monochrome image. Various structures can be considered for paper feeding, image formation, and paper ejection.
Variable printing performed in an image forming apparatus 10 will be described with reference to
A variable unique object region 212, which is used only once in the job in
Each of repeatedly used reusable object regions 211A, 211B, and 211C has image information and attribute information.
At the time of inspection processing, whether there is a difference is determined by printing answer image data and comparing scanned images of the reusable object regions 201A, 201B and 201C to the reusable object regions 211A, 211B, and 2110 of the answer images.
An inspection processing different from that for the reusable object region is performed in the variable unique object region. Examples of the different processing here include processing such as comparison not to a scanned answer image but with an image after RIP, comparison to a record value in a database that has been used at the time of generating a variable print job, and performing no inspection processing.
The answer images have a different number for each page. The contents of the reusable object and the variable unique object are determined for each page.
In each page, a variable unique object region 501 and a reusable object region 502 are arranged in an odd page, and variable reusable object regions 503A, 503B, and 503C, a variable unique object region 504, a reusable object region 505, variable reusable object regions 506A and 506B are arranged in an even page.
In the embodiment, each of three types: “A”, “B” and “C” of reusable object regions 701A, 701B and 701C is arranged on the entire surface of each page. A blank object region 702 surrounded by a broken line indicates a variable unique object. The object region 702 is superimposed on the reusable object regions. Although a part of the reusable object is arranged below the broken-line region, the entire region is subject to inspection processing as the variable unique object region.
When the processing is started, answer image input data for each page is generated (step s1).
In the above-described step, layout data of all pages is read, and the arrangement information on a reusable object and a variable unique object is extracted. The layout data may be read on layout generating application software for variable printing, and may be read at the timing immediately before performing RIP on a variable printing format (e.g., PPML and PDF/VT) with a printer (controller). The variable printing format is generated on the above-described application.
Arrangement patterns for each page are calculated based on these pieces of arrangement information, and answer image data is generated by the number of the arrangement patterns. More specifically, when a plurality of images is arranged as the reusable objects with respect to the same object region of each page, answer image data is generated by the number of the arranged images. When a plurality of regions is exhibited, answer images are generated for the number of combinations. Meanwhile, when variable (unique) objects are arranged in the same object region of each page, the number of answer images is not influenced.
Data for variable printing is generated, and associated with the corresponding answer image input data (step s2). That is, generation processing (RIP) for variable print data is performed on each page, and association with the answer images is performed in the step.
It should be noted that, in generating the variable print data, a layout is specified by a print instruction from a user. In order to assign each image to the specified layout, a record is extracted from, for example, a customer database, and applied to a layout frame. The image is mapped to a field whose layout has been designated, and the variable print data is generated. The processing is repeated until composition of one page is completed.
When the composition of one page is completed, for example, identification information for identifying printed matter and a file name of an image that has been mapped to each field are barcoded and added to the variable print data so as to compose the page. The processing is repeated until, for example, the customer database is finished.
A character and an image that have been registered as a variable object are inserted into a variable region. A character that has been registered as a reusable object is inserted in a fixed character region. An image that has been registered as a reusable object is inserted into a fixed image region. Other regions are blank.
Only an answer image is printed out, and a result obtained by scanning the result is confirmed (step s3). The output of answer images is repeated until a user can determine that there is no problem (step s4).
When the user determines that the image that has been printed out has no problem, the image is registered as an answer image (step s5).
It should be noted that the registration of an answer image is not limited to a specific method. For example, an image that has already been used for printing and has no abnormality in inspection processing may be used.
A type of setting may be performed. In the setting, a preview of an image scanned at the time of creating the answer image is displayed, a variable region is manually set on the display screen, and no inspection processing is performed.
After the above-described processing is completed, the output of variable printing is formally started (step s6). After outputting each page, an image is scanned and compared to the preliminarily associated answer image (step s7).
Following the result of the comparison, it is determined whether the output image has a problem (step s8). It should be noted that whether the output image has a problem can be determined by an appropriate determination method, and the determination method in the invention is not limited to a specific method. For example, whether a defect is on paper can be determined by detecting difference by comparing a read image to an answer image and being based on the detection result of the difference. In addition, instead of determining all parts where difference has been detected as defects, a part having difference exceeding a threshold value set by the user can be determined as a defect.
When the output image has no problem (Yes in step s8), it is determined whether all images have been output (step s9). When not all images have been output (No in step s9), the processing proceeds to step s6, and the next page is printed. When an abnormality is detected (No in step s8), the processing proceeds to step s6, and the page is output again. The processing is repeated until a normal output is performed.
These pieces of processing are repeated until all pages are output. When all pages are output (Yes in step s9), all pieces of processing are completed.
In the embodiment, the above-described variable region can be automatically set. In addition, the inspection accuracy of a repeatedly used variable object can be improved by comparing the variable object to the print-out scanned image.
In variable printing, even when the same reusable object is used, the adhesion characteristics of toner or ink change depending on the position of paper to be primed, and slight difference is caused by how light hits a scanner at the time when an answer image is created. In the embodiment, the user views a print result first. An image that has been determined as having no problem in quality is stored as an answer image and used for comparison. Consequently, abnormality during printing can be detected.
Although embodiments of the present invention have been described and illustrated in detail, the disclosed embodiments are made for purposes of illustration and example only and not limitation. The scope of the present invention should be interpreted by terms of the appended claims. Appropriate changes to the above-described embodiments can be made without departing from the scope of the invention.
Number | Date | Country | Kind |
---|---|---|---|
2018-199017 | Oct 2018 | JP | national |