Patent ID: 12260569

DETAILED DESCRIPTION

Hereinafter, an exemplary embodiment of the present disclosure will be described in detail and with reference to the attached drawings.

(Configuration of Information Processing System)

FIG.1is a diagram illustrating an overall configuration of an information processing system1to which the present exemplary embodiment is applied.

The information processing system1includes an image processing device10and a client terminal50connected over a network90. The network90is a network such as a local area network (LAN) or the Internet, for example. Note that the image processing device10and the client terminal50may also be connected directly without going through the network90by a communication method such as infrared communication, visible light communication, near field communication, Bluetooth (registered trademark), or RFID (registered trademark), for example. Also, although only a single client terminal50is illustrated inFIG.1, multiple client terminals50may be connected to the network90.

The image processing device10is an information processing device including a function of forming an image on a recording medium, a function of reading an image formed on a recording medium, a function of transmitting and receiving image information through communication, and the like as basic functions. The image information transmitted and received by the image processing device10includes the data of an image to be formed on a recording medium, information relevant to forming an image on a recording medium, and the like. Examples of the information relevant to forming an image on a recording medium include the size of the outputted recording medium, the color mode (for example, full color or black and white) when the image is formed, and the number of copies to be outputted. Note that in the present exemplary embodiment, the recording medium is paper.

When performing a process of forming an image onto paper as the recording medium (hereinafter referred to as “printing”), the image processing device10inspects whether or not the printing has been performed correctly. Specifically, the data of the image to be printed is treated as the data of a correct image while the data of an image generated by a process of reading the image printed onto the paper is treated as the data of the image to be inspected, and the two sets of data are compared. Additionally, the presence or absence of an inexpediency in the process of printing is determined on the basis of a difference detected from the result of comparing the two sets of data. The difference is detected according to a predetermined detection condition. Examples of inexpediencies in the printing process include “specks” caused by ink or the like adhering to unintended locations, “voids” in locations where printing is missing, and “light print” in locations where printing is incomplete.

The image processing device10performs the following process in the above inspection. Namely, the image processing device10acquires information related to image periodicity included in the data of the correct image treated as the data of a first image to be compared and the data of the image to be inspected treated as the second image to be compared. “Image periodicity” refers to a repeating pattern of the same or similar colors, shapes, characters, or the like occurring in an image.

On the basis of the acquired information related to image periodicity, the image processing device10corrects predetermined information for an alignment to be performed when comparing the data of the correct image to the data of the image to be inspected. Thereafter, the image processing device10controls the alignment of the data of the correct image and the data of the image to be inspected on the basis of the corrected content. Note that specific details about the process by the image processing device10will be described later.

The client terminal50is an information processing device such as a personal computer, a tablet, or a smartphone operated by a user U. The client terminal50creates or acquires the data of an image to be printed by the image processing device10on the basis of operations by the user U. Thereafter, the client terminal50causes printing to be performed by transmitting the created or acquired data of an image together with information relevant to printing (such as the paper size, the color mode, and the number of copies to be outputted, for example) to the image processing device10.

The client terminal50also receives and outputs a determination result transmitted from the image processing device10. Specifically, the client terminal50receives and outputs a result of determining the presence or absence of an inexpediency in the printing process for each character transmitted from the image processing device10. For example, the client terminal50displays the determination result transmitted from the image processing device10on a display in a form visible to the user U.

Note that the functions of the device and terminal forming the information processing system1described above are an example, and it is sufficient if the functions described above are provided for the information processing system1as a whole. For this reason, some or all of the functions described above may also be executed in a distributed or cooperative way within the information processing system1. For example, some or all of the functions of the image processing device10may be functions of the client terminal50. In addition, some of all of the functions of the image processing device10may also be delegated to a server or the like not illustrated. This arrangement makes it possible to expedite processes by the information processing system1as a whole, and also cause processes to complement each other.

(Hardware Configuration of Image Forming Device)

FIG.2is a diagram illustrating a hardware configuration of the image forming device10.

The image processing device10includes a control unit11, a memory12, a storage unit13, a communication unit14, an operation unit15, a display16, a reading unit17, and an image forming unit18. These components are connected by a data bus, an address bus, a Peripheral Component Interconnect (PCI) bus, and the like.

The control unit11is a processor that controls operations by the image processing device10through the execution of various software such as an operating system (OS; basic software) and application software. The control unit11includes a central processing unit (CPU), for example. The memory12is a storage area that stores various software and data used in the execution thereof, and is used as a work area when performing computations. The memory12is random access memory (RAM), for example.

The storage unit13is a storage area that stores information such as input data for various software and output data from various software, and for example, an image database (DB)801and an alignment information DB802are stored as databases for storing various information. In the image DB801, the data of the correct image is stored in association with the data of the image to be inspected. Also, in the alignment information DB802, predetermined information for the alignment performed when comparing the data of the correct image to the data of the image to be inspected is stored.

The storage unit13includes a component such as a hard disk drive (HDD), a solid-state drive (SSD), or semiconductor memory used to store information such as programs and various setting data, for example. The communication unit14transmits and receives data over the network90or according to a communication method such as infrared communication. The communication unit14transmits and receives data with respect to the client terminal50(seeFIG.1) and external equipment.

The operation unit15includes a keyboard, a mouse, and mechanical buttons and switches, for example, and receives input operations. The operation unit15also includes a touch sensor forming a touch panel integrated with the display16. The display16displays images, text information, and the like. The display16is a device such as a liquid crystal display or an organic electroluminescence (EL) display used to display information, for example.

The reading unit17reads an image recorded onto paper as a recording medium. The reading unit17is a device such as a charge-coupled device (CCD) scanner in which light from a light source is radiated onto a document and the reflected light therefrom is focused by a lens and sensed by a CCD, or a contact image sensor (CIS) scanner in which light from LED light sources is successively radiated onto a document and the reflected light therefrom is sensed by a CIS.

The image forming unit18forms an image onto a recording medium. Specifically, for example, the image forming unit18forms and outputs an image based on image information onto paper treated as the recording medium according to what is called an electrophotographic system that forms a toner image onto the paper, according to what is called an inkjet system that propels ink onto the paper, or the like. The image processing device10includes the image forming unit18that forms an image onto paper treated as the recording medium, and therefore functions as an image forming device.

(Hardware Configuration of Client Terminal)

The hardware configuration of the client terminal50is provided with a similar configuration to the hardware configuration of the image processing device10illustrated inFIG.2, with the exception of the reading unit17and the image forming unit18. For this reason, an illustration and description of the hardware configuration of the client terminal50is omitted.

(Functional Configuration of Control Unit of Image Processing Device)

FIG.3is a diagram illustrating a functional configuration of the control unit11of the image processing device10.

The control unit11of the image processing device10functions as an image acquisition unit101, a periodicity information acquisition unit102, an alignment information acquisition unit103, an information correction unit104, an alignment control unit105, a difference detection unit106, a determination unit107, and an output control unit108.

The image acquisition unit101acquires the data of the correct image and the data of the image to be inspected which are to be compared. Specifically, the image acquisition unit101acquires the data of the correct image stored in advance in the image DB801(seeFIG.2) of the storage unit13. As described above, the data of the correct image is the data of an image that is created or acquired by the client terminal50, and then transmitted to the image processing device10for printing.

The periodicity information acquisition unit102acts as an acquirer that acquires the information related to image periodicity included in the data of the correct image and the data of the image to be inspected which are acquired by the image acquisition unit101. Specifically, the periodicity information acquisition unit102acquires the information related to image periodicity from information related to an object included in the data of the correct image and the data of the image to be inspected, information related to a frequency of the data of the correct image and the data of the image to be inspected, or information inputted separately by the user U.

Of the information acquired by the periodicity information acquisition unit102, the information related to an object in the data of the correct image and the data of the image to be inspected includes, for example, information about what is called tiling, in which a single image is printed multiple times, information about what is called N-up, in which multiple images are printed together on a single sheet, or the like. Also, the information related to a frequency of the data of the correct image and the data of the image to be inspected includes, for example, information obtained by frequency analysis of an image converted by a Fourier transform process that converts from the spatial domain to the spatial frequency domain, and the like.

The information related to image periodicity acquired from the information related to an object included in the data of the correct image and the data of the image to be inspected, the information related to a frequency of the data of the correct image and the data of the image to be inspected, or the information inputted separately by the user U includes, for example, information about the position, size, and number of a region that acts as a periodic unit. The “region that acts as a periodic unit” refers to a region indicating the smallest unit of a pattern of the same or similar colors, shapes, characters, or the like. For example, in an image in which a pattern containing the single letter “a” is arranged repeatedly, the region where the single letter “a” exists is the “region that acts as a periodic unit”.

The alignment information acquisition unit103acquires predetermined information for the alignment. Specifically, the alignment information acquisition unit103acquires predetermined information for the alignment performed when comparing the data of the correct image and the data of the image to be inspected, which is stored in the alignment information DB802of the storage unit13(seeFIG.2).

The information correction unit104acts as a corrector that corrects the predetermined information for aligning the data of the correct image and the data of the image to be inspected on the basis of the information related to image periodicity acquired by the periodicity information acquisition unit102. Specifically, as the predetermined information for aligning the data of the correct image and the data of the image to be inspected, the information correction unit104corrects at least one of information indicating a region to be aligned between the data of the correct image and the data of the image to be inspected and information indicating a search volume of a region to be aligned. Hereinafter, the process of correcting the predetermined information for aligning the data of the correct image and the data of the image to be inspected may be referred to as the “information correction process” in some cases.

As the information correction process, the information correction unit104may consider the consistency of shape and size between a region to be aligned and the region that acts as a periodic unit when correcting information indicating a region to be aligned between the data of the correct image and the data of the image to be inspected, and also when correcting information indicating a search volume of the region to be aligned. For example, in the case where the region to be aligned and the region that acts as a periodic unit are of a consistent shape and size, and the search volume of the region to be aligned also matches, the information correction unit104determines that the issue of alignment at an unintended position will not occur. For this reason, the information correction unit104does not correct the predetermined information for the alignment.

As another example, in the case where the region to be aligned and the region that acts as a periodic unit are of a consistent shape and size, but the search volume of the region to be aligned is too large, the information correction unit104determines that there is a possibility that alignment at an unintended position may occur. For this reason, the information correction unit104corrects the information indicating the search volume of the region to be aligned. In this case, the information correction unit104corrects the information so as to narrow the search volume of the region to be aligned.

Also, when correcting the information indicating the region to be aligned between the data of the correct image and the data of the image to be inspected, and also when correcting the information indicating the search volume of the region to be aligned, the information correction unit104may reference information indicating an outer edge of the paper on which the image to be inspected is printed. For example, the information correction unit104references the information indicating the outer edge of the paper on which the image to be inspected is printed as a substitute for attaining fewer incorrect position determinations from only template matching described later.

To correct the information indicating the region to be aligned, the information correction unit104may, for example, cause the shape and size of the region to be aligned to match the shape and size of the region that acts as a periodic unit. As another example, to correct the information indicating the search volume of the region to be aligned, the information correction unit104may cause the shape and size of the region indicating the search volume to match the shape and size of the region to be aligned. Note that a specific example and the flow of the information correction process by the information correction unit104will be described later with reference toFIGS.5and6.

In the case where the predetermined information for aligning the data of the correct image and the data of the image to be inspected is acquired or is corrected by the information correction unit104, the alignment control unit105controls the alignment in the comparison between the data of the correct image and the data of the image to be inspected on the basis of the correction information about the predetermined information for aligning the data of the correct image and the data of the image to be inspected.

The difference detection unit106uses a predetermined detection condition to control the detection of the difference between the data of the correct image and the data of the image to be inspected. The determination unit107determines the presence or absence of an inexpediency in the process of printing by the image processing device10. Specifically, the determination unit107determines the presence or absence of an inexpediency in the process of printing by the image processing device10by determining the presence or absence of an inexpediency in the printing process for each character on the basis of the difference detected by the difference detection unit106.

The output control unit108controls the outputting of the determination by the determination unit107. Specifically, the output control unit108controls the transmission of the determination result to the client terminal50and causes the determination result to be outputted to the client terminal50. For example, the output control unit108controls the display of the client terminal50to display the determination result in a form visible to the user U.

(Processes by Image Processing Device)

FIG.4is a flowchart illustrating an overall flow of processes by the image processing device10.

The image processing device10acquires the data of each of the correct image and the image to be inspected (step401, YES), and if information related to image periodicity exists in the data of the images acquired in step401(step402, YES), the image processing device10acquires the information related to image periodicity (step403). In contrast, in the case where the data of each of the correct image and the image to be inspected is not acquired (step401, NO), the image processing device10repeats the process of step401until the data of each of the correct image and the image to be inspected is acquired. Also, in the case where information related to image periodicity does not exist in the data of the images acquired in step401(step402, NO), the image processing device10returns to the process of step401.

If predetermined information for aligning the data of the correct image and the data of the image to be inspected is acquired (step404, YES), the image processing device10performs the information correction process (step405). Note that the details of the flow of the information correction process will be described later with reference toFIG.6. In contrast, in the case where the predetermined information for aligning the data of the correct image and the data of the image to be inspected is not acquired (step404, NO), the image processing device10repeats the process of step404until the predetermined information for aligning the data of the correct image and the data of the image to be inspected is acquired.

The image processing device10performs alignment enabling comparison of the data of the correct image and the data of the image to be inspected, on the basis of the information corrected by the information correction process of step405or the uncorrected information, that is, the predetermined information for aligning the data of the correct image and the data of the image to be inspected (step406). Additionally, the image processing device10uses a predetermined detection condition to control the detection of the difference between the data of the correct image and the data of the image to be inspected (step407).

If a difference between the data of the correct image and the data of the image to be inspected is detected (step408YES), the image processing device10determines the presence or absence of an inexpediency in the printing process for each character on the basis of the degree of the detected difference (step409), and controls the outputting of the determination result (step410). In contrast, in the case where a difference between the data of the correct image and the data of the image to be inspected is not detected (step408, NO), the process ends.

(Information Correction Process)

FIG.5is a diagram illustrating a specific example of the information correction process.

The information correction process of step405inFIG.4described above is the process of correcting the predetermined information for aligning the data of the correct image and the data of the image to be inspected. To align the data of the correct image and the data of the image to be inspected, a technique referred to as template matching is used. Additionally, information indicating the outer edge of the paper and the like is used as auxiliary information for template matching. With this arrangement, a reduction in incorrect position determinations from only template matching may be attained.

Template matching refers to searching an entire image to determine whether or not an image with the same pattern as a partial image exists. For example, in the correct image under (Template Matching) inFIG.5, the rectangular portion enclosed by dashed lines is treated as the partial image and the entirety of the image to be inspected underneath is treated as the entire image. In this case, the region indicated by the partial region is the region to be aligned. Note that information indicating the region to be aligned is stored in the alignment information DB802(seeFIG.2) in the storage unit13of the image processing device10as the predetermined information for the alignment.

In template matching, a search is performed to determine whether or not an image with the same pattern as a partial image exists in an entire image. Specifically, a search is performed by overlaying the partial image onto the entire image and determining whether or not an image with same pattern exists in the entire image while moving the partial image in the directions of the arrows. How far to search is indicated as the search volume of the region to be aligned. Note that information indicating the search volume of the region to be aligned is stored in the alignment information DB802(seeFIG.2) in the storage unit13of the image processing device10as the predetermined information for the alignment.

In the case of using the template matching method to align an image in which a pattern containing the letter “a” is arranged periodically, for example, a process like the following is performed. First, (Example 1) inFIG.5is an example of the case of aligning an image in which the pattern of the letter “a” is arranged three times each horizontally and vertically, for a total of nine patterns. In this example, the partial image indicating the region to be aligned is a region (1 unit) that acts a periodic unit, and furthermore, the search volume of the region to be aligned is also a region (1 unit) that acts as a periodic unit.

In this case, the partial image and the region to be aligned are of a consistent size and shape, and therefore the issue of alignment at an unintended position will not occur. For this reason, the predetermined information for the alignment is not corrected. Note that information indicating that the region that acts as a periodic unit is n units (where n is an integer value equal to or greater than 1) is stored in the alignment information DB802(seeFIG.2) in the storage unit13of the image processing device10as the predetermined information for the alignment.

Next, (Example 2) inFIG.5is an example of the case of aligning an image in which the pattern of the letter “a” is arranged six times each horizontally and vertically, for a total of 36 patterns. In this example, the partial image indicating the region to be aligned is a region (4 units) that acts a periodic unit, whereas the search volume of the region to be aligned is a region (16 units) that acts as a periodic unit. In this case, the search volume of the region to be aligned contains multiple regions matching the region (4 units) that acts as a periodic unit, and consequently there is a possibility that alignment at an unintended position may occur. Accordingly, an information correction process like the following is performed.

The following two examples are specific examples of the information correction process in (Example 2) in FIG.5. Of these, the first example is an example of correcting the information indicating the search volume of the region to be aligned. In this example, the shape and size of the region indicating the search volume is corrected to match the shape and size of the region to be aligned. Specifically, as illustrated by (Information Correction Process 1), the number of units (that is, n units) of the region that acts as a periodic unit indicating the search volume of the region to be aligned is corrected from 16 units to 4 units. With this arrangement, the partial image and the region to be aligned are made to match each other similarly to (Example 1) described above, thereby suppressing alignment at an unintended position.

The second example is an example of correcting the information indicating the region to be aligned and also correcting the information indicating the search volume of the region to be aligned. In this example, the shape and size of the region to be aligned is corrected to match the shape and size of the region (1 unit) that acts as a periodic unit, and additionally, the shape and size of the region indicating the search volume is corrected to match the shape and size of the region to be aligned.

Specifically, as illustrated by (Information Correction Process 2), the partial image indicating the region to be aligned is narrowed to correct the region that acts as a periodic region from 4 units to 1 unit. Also, the number of units (that is, n units) of the region that acts as a periodic unit indicating the search volume of the region to be aligned is corrected from 16 units to 1 unit. With this arrangement, the shape and size of the partial image and the region to be aligned are made to match each other similarly to (Example 1) described above, thereby suppressing alignment at an unintended position.

FIG.6is a flowchart illustrating a flow of the information correction process among the processes by the image processing device10. Hereinafter, the flow of the information correction process will be described with reference to the specific examples ofFIG.5described above.

The information correction process in step405ofFIG.4described above is a process of correcting the predetermined information for aligning the data of the correct image and the data of the image to be inspected on the basis of the information related to image periodicity, and is performed according to a flow like the one illustrated inFIG.6.

In the case where the region (n units) that acts as a periodic unit treated as the region to be aligned matches the search volume of the region to be aligned (step601, YES), the information correction process is ended without correcting the predetermined information for the alignment (step602). This is a process corresponding to (Example 1) ofFIG.5, for example.

In contrast, in the case where the search volume of the region to be aligned is larger than the region (n units) that acts as a periodic unit treated as the region to be aligned (step601, NO), and n=1 (step S603, YES), the image processing device10corrects the information indicating the search volume (step604). Specifically, the image processing device10performs the correction by narrowing the search volume such that the search volume matches the region (1 unit) that acts as a periodic unit treated as the region to be aligned.

Also, in the case where n is 2 or greater (step603, NO), the image processing device10corrects the information indicating the search volume only or corrects the information indicating the region to be aligned and the information indicating the search volume (step605). Specifically, in the case of correcting the information indicating the search volume only, the image processing device10performs the correction by narrowing the search volume to match the region to be aligned, as in (Information Correction Process 1) ofFIG.5described above, for example. Also, in the case of correcting the information indicating the region to be aligned and the information indicating the search volume, the image processing device10performs the correction by narrowing the region to be aligned and also narrowing the search volume such that the two match, as in (Information Correction Process 2) ofFIG.5described above, for example. According to the above, the information correction process ends and the flow proceeds to the process of step406inFIG.4described above.

The above describes an exemplary embodiment, but the present disclosure is not limited to the exemplary embodiment described above. Moreover, the effects exhibited by embodiments of the present disclosure of the present disclosure are not limited to those indicated in the exemplary embodiment described above. For example, the configuration of the information processing system1illustrated inFIG.1and the hardware configuration of the image processing device10illustrated inFIG.2are merely illustrative examples of achieving an objective of the present disclosure and are not particularly limiting. Moreover, the functional configuration of the image processing device10illustrated inFIG.3is also merely a non-limiting illustrative example and is not particularly limiting. It is sufficient if the information processing system1inFIG.1is provided with functions enabling the execution of the processes described above as a whole, and the specific functional configuration for achieving the functions is not limited to the example inFIG.3.

In addition, the order of the steps of the processes by the image processing device10illustrated inFIGS.4and6is merely an illustrative example and is not particularly limiting. The processes not only may be performed in a time series following the order of the steps illustrated in the drawings, but also may be performed in parallel or individually without strictly being processed in a time series. Also, the specific examples of the information correction process illustrated inFIG.5are merely examples and are not particularly limiting.

Additionally, in the exemplary embodiment described above, the paper to be read for inspection by the image processing device10is paper that has been printed by the image processing device10itself, but the paper is not limited thereto and may also be paper that has been printed by another image processing device10. In this case, the data of the correct image data is acquired from the image processing device10that performed the printing, the client terminal50that initially created the data of the correct image, or the like through a server not illustrated or an external storage medium or the like.

In the embodiments above, the term “processor” refers to hardware in a broad sense. Examples of the processor include general processors (e.g., CPU: Central Processing Unit) and dedicated processors (e.g., GPU: Graphics Processing Unit, ASIC: Application Specific Integrated Circuit, FPGA: Field Programmable Gate Array, and programmable logic device).

In the embodiments above, the term “processor” is broad enough to encompass one processor or plural processors in collaboration which are located physically apart from each other but may work cooperatively. The order of operations of the processor is not limited to one described in the embodiments above, and may be changed.

The foregoing description of the exemplary embodiments of the present disclosure has been provided for the purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure to the precise forms disclosed. Obviously, many modifications and variations will be apparent to practitioners skilled in the art. The embodiments were chosen and described in order to best explain the principles of the disclosure and its practical applications, thereby enabling others skilled in the art to understand the disclosure for various embodiments and with the various modifications as are suited to the particular use contemplated. It is intended that the scope of the disclosure be defined by the following claims and their equivalents.