Information processing apparatus, information processing system, information processing method, and recording medium

Abstract

An information processing apparatus includes: a reception unit to receive read data obtained by a sensor unit of an image reading apparatus reading a color chart; a storage unit to store reference data of a quality evaluation pattern included in the color chart; a positional misalignment determination unit configured to determine a misalignment of a read position of the read data; and an abnormality detection unit configured to detect an abnormality of the sensor unit. The abnormality detection unit calculates a difference between the read data and the reference data that correspond to a same position in the quality evaluation pattern based on a determination result obtained by the positional misalignment determination unit, and detects the abnormality based on whether the difference is greater than or equal to a threshold value.

Description

[DESCRIPTION][Title of Invention]INFORMATION PROCESSING APPARATUS, INFORMATION PROCESSING SYSTEM, INFORMATION PROCESSING METHOD, AND RECORDING MEDIUM [Technical Field]

[0001] The present disclosure relates to an information processing apparatus, an information processing system, an information processing method, and a recording medium. [Background Art]

[0002] To maintain the quality of printed materials, image forming apparatuses in the related art read a predetermined printed color chart and perform color adjustment. For example, in a technique in the related art, an image reading apparatus reads a check chart including color patches for check printed by an image forming apparatus after the color adjustment, and whether the printing quality of the image forming apparatus meets a reference is checked. When the image reading apparatus that reads an image such as a color chart is not in an appropriate state, the printing quality of the image forming apparatus is not correctly evaluated. Accordingly, in a technique in the related art, read data obtained by the image reading apparatus reading the color chart is compared with reference data corresponding to optical characteristics of the color chart to detect an abnormality of the image reading apparatus.

[0003] PTL 1 discloses an integrated configuration of a sample portion, a storage medium, and an interface. The sample portion is measured by an optical characteristic measurement apparatus to supply measured data. The storage medium stores identification data for identifying a kind of the sample portion and reference data corresponding to an optical characteristic of the sample portion. The interface transmits data stored in the storage medium to the optical characteristic measurement apparatus.[Citation List][Patent Literature]

[0004] [PTL 1] lapanese Unexamined Patent Application Publication No. 2006-153498[Summary of Invention][Technical Problem]

[0005] However, the technique in the related art does not take into account an influence of a positional misalignment between the read data and the reference data, and thus fails to appropriately detect an abnormality of the image reading apparatus when a quality evaluationpattern used as the sample has an in-plane unevenness. For example, when the quality evaluation pattern has a color unevenness in the vertical direction thereof, the value of the read data obtained by the image reading apparatus changes in the vertical direction. Likewise, the value of the reference data corresponding to the quality evaluation pattern also changes in the vertical direction because of the color unevenness of the quality evaluation pattern in the vertical direction. Thus, if the compared positions of the read data and the reference data are misaligned from each other in the vertical direction when the read data is compared with the reference data, the comparison is not correctly performed and the abnormality of the image reading apparatus is not appropriately detected.[Solution to Problem]

[0006] According to an embodiment of the present disclosure, an information processing apparatus includes a reception unit, a storage unit, a positional misalignment determination unit, and an abnormality detection unit. The reception unit receives read data obtained by a sensor unit of an image reading apparatus reading a color chart. The storage unit stores reference data of a quality evaluation pattern included in the color chart. The positional misalignment determination unit determines a misalignment of a read position of the read data. The abnormality detection unit detects an abnormality of the sensor unit. The abnormality detection unit calculates a difference between the read data and the reference data that correspond to a same position in the quality evaluation pattern by using a determination result obtained by the positional misalignment determination unit, and detects the abnormality based on whether the difference is greater than or equal to a predetermined threshold value. According to an embodiment of the present disclosure, an information processing system includes an image reading apparatus and the above-described information processing apparatus. The image reading apparatus includes a sensor unit. The sensor unit reads a color chart and a white reference plate.According to an embodiment of the present disclosure, an information processing method includes: receiving read data obtained by a sensor unit of an image reading apparatus reading a color chart; storing reference data of a quality evaluation pattern included in the color chart; determining a misalignment of a read position of the read data; and detecting an abnormality of the sensor unit. The detecting includes calculating a difference between the read data and the reference data that correspond to a same position in the quality evaluation pattern by using a determination result obtained in the determining, and detecting the abnormality based on whether the difference is greater than or equal to a predetermined threshold value.According to an embodiment of the present disclosure, a recording medium has recorded thereon a program that causes a computer system to execute an information processing method. The information processing method includes: receiving read data obtained by a sensor unit of an image reading apparatus reading a color chart; storing reference data of a quality evaluation pattern included in the color chart; determining a misalignment of a readposition of the read data; and detecting an abnormality of the sensor unit. The detecting includes calculating a difference between the read data and the reference data that correspond to a same position in the quality evaluation pattern by using a determination result obtained in the determining, and detecting the abnormality based on whether the difference is greater than or equal to a predetermined threshold value.[Advantageous Effects of Invention]

[0007] According to one or more embodiments of the present disclosure, even when a quality evaluation pattern has an in-plane unevenness, an influence of a positional misalignment between read data and reference data can be suppressed and an abnormality of an image reading apparatus can be appropriately detected.[Brief Description of Drawings]

[0008] A more complete appreciation of embodiments of the present disclosure and many of the attendant advantages and features thereof can be readily obtained and understood from the following detailed description with reference to the accompanying drawings.[FIG. 1]FIG. l is a diagram illustrating a configuration of an information processing system according to a first embodiment of the present disclosure.[FIG. 2]FIG. 2 is a perspective view of an example of a configuration of an image reading apparatus.[FIG. 3]FIG. 3 is a cross-sectional view of an example of a sensor unit of the image reading apparatus.[FIG. 4]FIG. 4 is a diagram for describing diffraction images and how light is received by an imaging device.[FIG. 5]FIG. 5 is a block diagram illustrating an example of a hardware configuration of the image reading apparatus.[FIG. 6]FIG. 6 is a block diagram illustrating an example of a hardware configuration of an information processing apparatus.[FIG. 7]FIG. 7 is a diagram illustrating an example of images included in a color chart.[FIG. 8A]FIG. 8A is a diagram illustrating an example of read data of a quality evaluation pattern and a position detection pattern obtained by the sensor unit through reading.[FIG. 8B]FIG. 8B is a diagram illustrating an example of read data of the quality evaluation pattern and the position detection pattern obtained by the sensor unit through reading.[FIG. 9]FIG. 9 is a block diagram illustrating a functional configuration of the information processing apparatus according to the first embodiment of the present disclosure.[FIG. 10]FIG. 10 is a flowchart illustrating an example of a processing procedure for detecting an abnormality of a sensor unit according to the first embodiment of the present disclosure. [FIG. 11]FIG. 11 is a flowchart illustrating an example of a processing procedure for detecting an abnormality of a sensor unit according to a second embodiment of the present disclosure. [FIG. 12]FIG. 12 is a block diagram illustrating a functional configuration of an information processing apparatus according to a third embodiment of the present disclosure.The accompanying drawings are intended to depict embodiments of the present disclosure and should not be interpreted to limit the scope thereof. The accompanying drawings are not to be considered as drawn to scale unless explicitly noted. Also, identical or similar reference numerals designate identical or similar components throughout the several views. [Description of Embodiments]

[0009] In describing embodiments illustrated in the drawings, specific terminology is employed for the sake of clarity. However, the disclosure of this specification is not intended to be limited to the specific terminology so selected and it is to be understood that each specific element includes all technical equivalents that have a similar function, operate in a similar manner, and achieve a similar result.Referring now to the drawings, embodiments of the present disclosure are described below.As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.An information processing apparatus, an information processing method, a program, and an information processing system according to embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings.

[0010] First EmbodimentFIG. l is a diagram illustrating a configuration of an information processing system 1 according to a first embodiment of the present disclosure. As illustrated in FIG. 1, the information processing system 1 includes an image reading apparatus 3 and an information processing apparatus 4 that are connected to each other via a network 5.

[0011] The information processing apparatus 4 is a personal computer (PC) that performs quality evaluation and management. The information processing apparatus 4 transmits an operation instruction to the image reading apparatus 3 and transmits and receives data to and from the image reading apparatus 3 via the network 5.

[0012] The image reading apparatus 3 (described below) is a spectral characteristics obtaining apparatus that reads predetermined printed image data (color chart) and is used for color adjustment in order to maintain the quality of printed materials created by an image forming apparatus. Note that the image reading apparatus 3 is not limited to the spectral characteristics obtaining apparatus, and may indicate any general apparatus that obtains electronic data of a color chart, such as an image scanner or a colorimeter.

[0013] In the description of embodiments of the present disclosure given below, an object from which spectral characteristics are obtained is, for example, an image-carrying medium such as a sheet. The object from which the spectral characteristics are obtained is referred to simply as a sheet. Some drawings illustrate directions using solid-line arrows. Among directions indicated by the respective arrows, an X-axis direction denotes a width direction of the sheet, a Y-axis direction denotes a sheet conveyance direction, and a Z-axis direction denotes a direction orthogonal to an X-Y plane.

[0014] FIG. 2 is a perspective view of an example of a configuration of the image reading apparatus 3. In FIG. 2, the image reading apparatus 3 includes a color data obtainer 20, sheet conveyors 30, 31, and 32, sheet sensors 41 and 42, a color-data-obtainer conveyor 40, a color chart for correction 50, and a controller 300.

[0015] The color data obtainer 20 includes a linear light source 60, a reduction imaging lens 70, and a sensor unit 80.

[0016] The sheet conveyors 30, 31, and 32 convey a sheet 100 in the Y-axis direction. The sheet conveyors 30, 31, and 32 each include, for example, a nip roller having two rollers. As illustrated in FIG. 2, the sheet conveyors 30, 31, and 32 each nip the sheet 100 with the nip roller and rotate the nip roller to convey the sheet 100.

[0017] For example, the sheet sensors 41 and 42 each irradiate the sheet 100 with light and detect reflected light with a photodiode or the like. Based on outputs from the sheet sensors 41 and 42, it is detected that the sheet 100 is at a position of a color-data obtaining area 21 for the color data obtainer 20.

[0018] A reference plane for measurement 22 is, for example, a wide guide plate made of a sheet metal painted in white or black. The painted color is black when the reference plane for measurement 22 conforms to an International Organization for Standardization (ISO) standard or is used for calibration of an image forming apparatus. The painted color is white when a color profile for printing is created. The color condition changes depending on the purpose, and the reference plane for measurement 22 is replaceable.

[0019] The color-data-obtainer conveyor 40 conveys the color data obtainer 20 in the width direction (X-axis direction) of the sheet 100. The color-data-obtainer conveyor 40 is, for example, a conveyance stage including, for example, a ball screw and a guide.

[0020] The color chart for correction 50 is used to correct a transformation matrix that is used to calculate the spectral characteristics. A white area among components of the color chart for correction 50 is used, as a white reference plate 51 for calibration, to determine the presence or absence of an abnormality of the image reading apparatus 3.

[0021] The image reading apparatus 3 can simultaneously obtain spectral characteristics at a plurality of positions in the Y-axis direction in the color-data obtaining area 21 of the sheet 100.

[0022] The linear light source 60 illuminates the color-data obtaining area 21 with the linear light in a direction inclined by approximately 45 degrees with respect to a normal to the sheet 100. The linear light source 60 illuminates an appropriate area in the color-data obtaining area 21 such that reflected light from an area other than the color-data obtaining area 21 of the sheet 100 is not incident on the sensor unit 80.

[0023] As the linear light source 60, for example, an array of white light-emitting diodes (LEDs) that have an intensity for substantially the entire range of visible light may be used. However, no limitation is intended thereby, and a lamp light source or a fluorescent lamp such as a coldcathode tube may be used as the linear light source 60.

[0024] It is desirable that the linear light source 60 emit light in a wavelength range for spectral separation and irradiate the entire color-data obtaining area 21 with a uniform intensity. A collimator lens that concentrates the light emitted from the linear light source 60 and irradiates the sheet 100 with parallel light or converging light may additionally be provided.

[0025] The reduction imaging lens 70 is disposed such that the optical axis thereof is parallel to the normal to the sheet 100, and has a function to form an image of the reflected light, i.e., the reflected light flux from the sheet 100 on an incident plane of the sensor unit 80 with a predetermined magnifying power. By adding the image-side telecentric characteristics to thereduction imaging lens 70, the chief ray of the light flux incident on the imaging plane is made approximately parallel to the optical axis. The reduction imaging lens 70 may include a plurality of lenses.

[0026] By adding the image-side telecentric characteristics to the reduction imaging lens 70, the chief ray of the light flux incident on the imaging plane can easily be made approximately parallel to the optical axis. However, in some embodiments, the image-side telecentric characteristics are not added to the reduction imaging lens 70. In such a case, similar effects can be achieved by adjusting, for example, the positional relationship between each pinhole of a pinhole array 81 (described later) and a corresponding lens of a lens array 82 (described later) in accordance with the inclination of the chief ray at a corresponding position on the imaging plane.

[0027] The sensor unit 80 has a function to spectrally separate the diffused reflected light of the light emitted to the sheet 100 and a function to output a signal in response to the reception of the separated spectral components of the light.

[0028] The optical system illustrated in FIG. 2 is a so-called 45 / 0 optical system in which the illumination light emitted from the linear light source 60 is obliquely incident on the sheet 100 at approximately 45 degrees and the sensor unit 80 receives the light diffusely reflected by the sheet 100 in the vertical direction. However, the configuration of the optical system is not limited to that in FIG. 2. For example, the optical system according to the present embodiment may be a so-called 0 / 45 optical system in which the illumination light emitted from the linear light source 60 is perpendicularly incident on the sheet 100 and the sensor unit 80 receives the light diffusely reflected by the sheet 100 at 45 degrees.

[0029] The configuration of the sensor unit 80 will be described.

[0030] FIG. 3 is a cross-sectional view of an example of the sensor unit 80 of the image reading apparatus 3. FIG. 3 illustrates a part of a cross section parallel to a Y-Z plane of the sensor unit 80.

[0031] As illustrated in FIG. 3, the sensor unit 80 includes the pinhole array 81, the lens array 82, a diffraction element 83, and an imaging device 84. The sensor unit 80 also includes a package 85, a spacer 86, a cover glass 87, and glass bases 88a, 88b, and 88c.

[0032] The pinhole array 81 has pinholes that serve as openings through which the light reflected from the sheet 100 passes. The pinholes are arranged at respective positions on the imaging plane where the images of the light incident from the reduction imaging lens 70 are formed in the Z-axis direction, and are arrayed at predetermined intervals in the Y-axis direction.FIG. 3 illustrates an example in which three pinholes are arrayed in the Y-axis direction.

[0033] The pinhole array 81 is integrally provided on the glass base 88a that is transparent and flat and serves as a frame with optical transparency. For example, a thin metal film such as a film made of nickel is evaporatively deposited on a transparent glass base, and openings that serve as the pinholes are arrayed, so that the pinhole array 81 is formed. The light flux of the reflected light from individual points in the color-data obtaining area 21 of the sheet 100 is extracted by the individual pinholes provided in the pinhole array 81.

[0034] However, the configuration of the sensor unit 80 is not limited to the configuration including the pinhole array 81. The sensor unit 80 may include a slit array including rectangular openings or an oblique slit array in which rectangular slits are inclined with respect to the Y- axis direction.

[0035] A face of the glass base 88a opposite to the face on which the reflected light from the sheet 100 is incident is bonded to a face of the glass base 88b, which is transparent and flat and serves as a frame with optical transparency. A face of the glass base 88b opposite to the face bonded to the glass base 88a has lenses that are arrayed at predetermined intervals in the Y- axis direction.

[0036] FIG. 4 is a diagram for describing diffraction images and how light is received by the imaging device 84. FIG. 4 corresponds to an example in which three lenses are arrayed in the Y-axis direction as illustrated in FIG. 3 to form the lens array 82. Each of the lenses of the lens array 82 concentrates the light flux that has passed through the corresponding one of the pinholes of the pinhole array 81, and forms an image on the imaging device 84.

[0037] In the lens array 82 illustrated in FIG. 3, a plurality of lenses 82a are arrayed in a line in the Y- axis direction. Each of the lenses 82a of the lens array 82 has a function to transform the diffused light flux that has passed through a corresponding one of the openings of the pinhole array 81 into a weakly diffused light flux.

[0038] The weakly diffused light flux is a diffused light flux closer to a parallel light flux than an incident diffused light flux. In other words, the weekly diffused light flux is a diffused light flux having a smaller degree of diffusion, that is, a weaker degree of diffusion than the incident diffused light flux.

[0039] Each of the lenses 82a of the lens array 82 is arranged at a position corresponding to the corresponding one of the openings of the pinhole array 81, and has a diameter that allows allthe light that has passed through the corresponding opening to be incident thereto. In some embodiments, the shape of the lenses 82a in plan view is not circular.

[0040] In the present embodiment, the pinhole array 81 and the lens array 82 are arranged with the glass base 88a and the glass base 88b interposed therebetween. However, no limitation is intended thereby. Thicknesses of the glass base 88a and the glass base 88b are determined such that optical -path lengths of the pinhole array 81 and the lens array 82 are shorter than an object-side focal length of the lenses 82a of the lens array 82. It is desirable that the lens array 82 be shielded against light except for apertures of the lenses 82a to omit the stray light.

[0041] In the sensor unit 80, the glass base 88c that is transparent and flat and serves as a frame with optical transparency is arranged to face the lens array 82 in the Z-axis direction. The glass base 88b and the glass base 88c are bonded to each other with the spacer 86 interposed therebetween.

[0042] The spacer 86 is a member that gives a certain gap or space between the glass base 88b and the glass base 88c, and is, for example, a flat metal plate member having at least one through hole appropriately arranged at a planar face thereof. On a face of the spacer 86 that faces the lens array 82, a non-through-hole portion of the spacer 86 is in contact with and is bonded to a lens-free portion of the glass base 88b.On a face of the spacer 86 that faces the diffraction element 83, a non-through-hole portion of the spacer 86 is in contact with and is bonded to any desired portion of the glass base 88c. With such a configuration, a certain gap or space is given between the glass base 88b and the glass base 88c. The at least one through hole may be small holes that accommodate the respective lenses 82a of the lens array 82, or a large hole that accommodates the plurality of lenses 82a.

[0043] The face of the glass base 88c that faces the lens array 82, i.e., on which the reflected light from the sheet 100 is incident, is provided with the diffraction element 83. The diffraction element 83 has a sawtooth shape formed at predetermined intervals on the glass base 88c, and functions as a diffraction grating that diffracts and spectrally separates the incident light. The diffraction element 83 spectrally separates the light flux that has passed through each of the lenses 82a of the lens array 82. A diffraction image corresponding to each light flux is formed on the imaging device 84.

[0044] It is desirable that, as the diffraction element 83, a blazed grating with an enhanced diffraction efficiency for the Ist-order diffracted light be used. The use of a blazed grating as the diffraction element 83 can enhance the diffraction efficiency of only the Ist-order diffracted light, which can enhance the light utilization efficiency of the optical system. With such aconfiguration, a signal of sufficient quality can be obtained in a relatively short time, and the length of time to obtain the spectral characteristics can be shortened.

[0045] The imaging device 84 is a linear sensor in which a plurality of pixels are arrayed in the Y- axis direction. The imaging device 84 uses multiple light-receiving elements arranged at different positions to receive the light beams of the respective diffraction images formed by the lens array 82 and the diffraction element 83 and obtain a light intensity in a predetermined wavelength range of the incident light. As the imaging device 84, for example, a metal oxide semiconductor (MOS) image sensor, a complementary metal oxide semiconductor (CMOS) image sensor, or a charge-coupled device (CCD) image sensor may be used.

[0046] The diffraction axis of the diffraction element 83 is inclined by an angle a with respect to the Y-axis direction. As illustrated in FIG. 4, the diffraction images inclined by the angle a with respect to the Y-axis direction are incident on the imaging device 84. FIG. 4 illustrates three diffraction patterns that are adjacent to one another in the Y-axis direction and each include a Oth-order diffraction image A, a +lst-order diffraction image B, and a +2nd-order diffraction image C. The imaging device 84 is arranged to receive the +lst-order diffraction images B in the diffraction patterns. In FIG. 4, the three +lst-order diffraction images A formed by the three lenses 82a of the lens array 82 are received in respective pixel regions 84a, 84b, and 84c of the imaging device 84 and are converted into electrical signals. The electrical signals are output as color data obtained by the sensor unit 80.

[0047] As described above, the image reading apparatus 3 successfully removes crosstalk between the diffraction images and determines spectral characteristics of the sheet 100 based on the +lst-order diffraction images B. In the following description, the +lst-order diffraction images B may be referred to simply as diffraction images.

[0048] The imaging device 84 is fixed inside the package 85. The package 85 has an opening, which is covered with the cover glass 87 that is transparent and serves as a frame with optical transparency. The cover glass 87 is bonded to the face of the glass base 88c where the diffraction element 83 is not formed.

[0049] Optically, one pinhole of the pinhole array 81, one lens 82a of the lens array 82 that corresponds to the one pinhole, a portion of the diffraction element 83 through which the light flux from the one lens 82a passes, and a portion of the row of pixels of the imaging device 84 together have a function of one spectroscope. Accordingly, a portion having the function of one spectroscope is referred to as a sensor below.

[0050] FIG. 3 illustrates three sensors. However, no limitation is intended thereby, and the sensor unit 80 may include many sensors. For example, when the imaging device 84 having 1024 pixels is used and the above portion of the rows of pixels has 10 pixels, 102 sensors can be obtained. The sensor unit 80 is a linear sensor in which such sensors are arrayed in the Y-axis direction, i.e., the sheet conveyance direction. While the color data obtainer 20 is conveyed in the X- axis direction, the sensor unit 80 reads color data in an area of the sheet equivalent to a read range (length) of the sensor unit 80 x a width over which the color data obtainer 20 is conveyed.

[0051] In the optical system for spectral separation included in the sensor unit 80, the relative positional misalignments between the imaging device 84 and the diffraction images formed by the pinhole array 81, the lens array 82, and the diffraction element 83 have a great influence on the accuracy in the acquisition of the spectral characteristics. In the present embodiment, to control such positional misalignments, the pinhole array 81, the lens array 82, the diffraction element 83, and the imaging device 84 are overlaid on top of one another in layers in the optical-axis direction of the reduction imaging lens 70 and bonded together in an integrated manner.

[0052] An overview of the controller 300 of the image reading apparatus 3 will be described.

[0053] FIG. 5 is a block diagram illustrating an example of a hardware configuration of the image reading apparatus 3.

[0054] The controller 300 includes a main controller 300A, an input / output (I / O) 305, a light-source driving circuit 306, an imaging-device controller 307, a motor driving circuit 308, a hard disk drive (HDD) 309, and a Peltier-device controller 310.

[0055] The main controller 300A includes a central processing unit (CPU) 301, a read-only memory (ROM) 302, and a random access memory (RAM) 303.These components are electrically connected to each other via a system bus 320.

[0056] The CPU 301 centrally controls the operation of the image reading apparatus 3. The CPU 301 executes a program stored in, for example, the ROM 302 by using the RAM 303 as a work area to control the entire operation of the image reading apparatus 3 and implement various functions described below. The HDD 309 stores, for example, the obtained color data.

[0057] The I / O 305 receives, for example, detection signals from the sheet sensors 41 and 42.

[0058] The light-source driving circuit 306 is an electric circuit that outputs, based on a received control signal, a driving signal such as a driving voltage to cause the linear light source 60 to emit light.

[0059] The imaging-device controller 307 controls, based on a received control signal, imaging performed by the imaging device 84 of the sensor unit 80. Image data obtained by the imaging device 84 through imaging is sent to and stored in the HDD 309 as color data through the imaging-device controller 307. The Peltier-device controller 310 controls a Peltier device 90 that controls the temperature of the imaging device 84 constant.

[0060] The motor driving circuit 308 is an electric circuit that outputs, based on a received control signal, a driving signal such as a driving voltage to each of motors that cause the sheet conveyor 30 and the color-data-obtainer conveyor 40 to operate.

[0061] Note that part or all of the control process performed by the CPU 301 may be implemented by an electronic circuit such as a field-programmable gate array (FPGA) or an applicationspecific integrated circuit (ASIC).

[0062] A hardware configuration of the information processing apparatus 4 will be described.

[0063] FIG. 6 is a block diagram illustrating an example of the hardware configuration of the information processing apparatus 4. As illustrated in FIG. 6, the information processing apparatus 4 includes a CPU 601, a ROM 602, a RAM 603, an auxiliary memory 605, a medium drive 607, a display 608 (display device), a network interface (I / F) 609, a keyboard 611, a mouse 612, and a digital versatile disc (DVD) drive 614.

[0064] The CPU 601 is a processor that controls the entire operation of the information processing apparatus 4. The ROM 602 is a nonvolatile memory that stores programs for the information processing apparatus 4. The RAM 603 is a volatile memory used as a work area for the CPU 601.

[0065] The auxiliary memory 605 is a memory such as an HDD or a solid state drive (SSD) that stores various kinds of data and programs.The medium drive 607 controls reading and writing of data from and to recording media 606 such as a flash memory under control of the CPU 601.

[0066] The display 608 is a display device, such as a liquid crystal display or an organic electroluminescence (EL) display, that displays various kinds of information such as a cursor, a menu, a window, characters, or an image.

[0067] The network I / F 609 is an interface for performing data communication with an external apparatus such as the image reading apparatus 3 via the network 5. The network I / F 609 is, for example, a network interface card (NIC) that supports Ethernet® and performs communication conforming to, for example, Transmission Control Protocol / Internet Protocol (TCP / IP).

[0068] The keyboard 611 is an example of an input device used for selecting characters, numbers, or various instructions, and for moving a cursor. The mouse 612 is another example of an input device used for selecting and executing various instructions, selecting a subject to be processed, or moving the cursor.

[0069] The DVD drive 614 is a device that controls reading and writing of data to and from a DVD 613 such as a DVD-ROM or DVD-recordable (DVD-R), which is an example of a removable storage medium.

[0070] The CPU 601, the ROM 602, the RAM 603, the auxiliary memory 605, the medium drive 607, the display 608, the network I / F 609, the keyboard 611, the mouse 612, and the DVD drive 614 are communicably connected to each other via a bus 610 such as an address bus or a data bus.

[0071] The hardware configuration of the information processing apparatus 4 illustrated in FIG. 6 is merely one example. In some embodiments, the information processing apparatus 4 does not include all of the components illustrated in FIG. 6 or includes another hardware component.

[0072] A color chart 2 used in the present embodiment will be described. For example, in response to a request to provide the color chart 2 from a user of the image reading apparatus 3, the color chart 2 is printed at a production facility of the image reading apparatus 3 and provided to the user. FIG. 7 is a diagram illustrating an example of images included in the color chart 2. The color chart 2 includes, as components thereof, an image of a quality evaluation pattern Pl, an image of an identification code P2, and an image of a position detection pattern P3.

[0073] The quality evaluation pattern Pl is an image including a plurality of strip color patches. The color patches have different colors. The colors of the color patches are, for example, 14 colors selected based on the standard tiles of British Ceramic Research Association (BCRA). However, other colors or the different number of colors may be used. A dimension of the color patches in the longitudinal direction is greater than a dimension of a read range L of the sensor unit 80.

[0074] The information processing apparatus 4 compares reference data representing the colors of the quality evaluation pattern Pl with read data obtained by the image reading apparatus 3 reading the quality evaluation pattern Pl to detect an abnormality of the sensor unit 80. The reference data is data generated by measuring the quality evaluation pattern Pl of the printed color chart 2 with a reference colorimeter or the image reading apparatus 3 at the shipment. Due to the printing characteristics, the colors of the quality evaluation pattern Pl may deviate from the desired colors even when the quality evaluation pattern Pl is printed using the same sheet type or printer. The reference data is different for each color chart 2. Thus, the quality evaluation pattern Pl included in the color chart 2 has a one-to-one correspondence with the reference data generated by measuring the quality evaluation pattern Pl, and is distinguished by the identification information such as a unique ID. The reference data is stored and managed in, for example, a data server of a production facility of the image reading apparatus 3 together with the identification information of the corresponding quality evaluation pattern Pl. To cope with the misalignment of the read position (described later), the measurement range of the reference data is wider than the read range L of the sensor unit 80.

[0075] The identification code P2 is an image representing the identification information corresponding to the quality evaluation pattern Pl. The information processing apparatus 4 identifies and obtains the reference data corresponding to the quality evaluation pattern Pl, based on the identification code P2 included in the read data obtained by the image reading apparatus 3, and uses the reference data to detect an abnormality of the image reading apparatus 3.

[0076] The identification code P2 in FIG. 7 is identification information that is coded by a combination of a plurality of color patches. In this example, the identification code P2 is made up of color patches of five colors, i.e., cyan (C), magenta (M), yellow (Y), black (K), and white (W). For example, each color is assigned one of numerical values of 0 to 4, and the resultant numeral is associated with the identification code P2.

[0077] Fixed combinations of colors are arranged on the respective ends of the identification code P2 to indicate the ends of the identification code P2 and specify the direction of the array of the plurality of color patches. For example, as illustrated in FIG. 7, two color patches on the left end are K and Y sequentially from the left, and two color patches on the right end are M and C sequentially from the left. Since the colors and orders of these four color patches are fixed, the color patches at the respective ends can be identified. This allows the direction of the identification code P2 to be specified. Thus, the color patches arranged at the left end and the right end of the identification code P2 are specifying information for specifying the direction of the identification code P2. Note that other colors or other arrangement may be used for the specifying information.

[0078] The identification code P2 above is made up of color patches of single colors such as C, M, Y, K, and W. Alternatively, the identification code P2 may include a color patch of a mixed color of a plurality of single colors. The number of color patches and the arrangement of the color patches are not limited to the example above. The identification code P2 may be formed using a color material of another color, or using a hard-to-see color patch, which is formed using transparent colorless toner or invisible red (IR) toner whose presence is recognized when irradiated with infrared rays.

[0079] In the identification code P2 in FIG. 7, a plurality of color patches excluding the specifying information represent information (color code information) to which the identification information is coded. The color patches of the identification code P2 are arranged such that adjacent color patches have different colors. The color code information represents a numerical value in the number of digits that corresponds to the number of color patches. By replacing the colors of the plurality of color patches of the color code information with numerical values of 0 to 4 assigned to the respective colors, the color code information is converted to a numerical value and thus the identification information can be obtained (decoded). When the image reading apparatus 3 supports reading of a barcode or Quick Response (QR) code®, the barcode or QR code made may be used as the identification code P2.

[0080] The position detection pattern P3 is an image for detecting a misalignment of a read position that occurs when the image reading apparatus 3 reads image data. The color patches of the quality evaluation pattern Pl have color unevenness in the vertical direction. Thus, a read position misalignment in the vertical direction changes the read data. Due to the color unevenness of the color patches in the vertical direction, the reference data also has a value that varies in the vertical direction. Therefore, to detect an abnormality, the read data and the reference data are to be aligned.

[0081] In FIG. 7, the position detection pattern P3 includes color patches of K and W that are adjacent to each other in the vertical direction, and the color patch of W indicates the normal range of the read position. FIGs. 8A and 8B are diagrams each illustrating an example of the read data of the quality evaluation pattern Pl and the position detection pattern P3 obtained by the sensor unit 80 through reading. In FIGs. 8A and 8B, top and bottom areas with oblique hatching indicate areas outside the read range of the sensor unit 80, and the read data is represented by an area other than the areas with oblique hatching. The read data illustrated in FIG. 8A indicates that the read position is normal since an area of the position detection pattern P3 includes the color patch of W alone and does not include the color patch of K. In contrast, the read data illustrated in FIG. 8B indicates that the read position is misaligned byAL in the Y-axis direction since the area of the position detection pattern P3 includes the color patch of K at a lower part thereof.

[0082] Functions implemented by the CPU 601 of the information processing apparatus 4 in accordance with a program stored in the ROM 602 or the auxiliary memory 605 will be described.

[0083] FIG. 9 is a block diagram illustrating of a functional configuration of the information processing apparatus 4 according to the present embodiment. As illustrated in FIG. 9, the information processing apparatus 4 includes a reception unit 201, a storage unit 202, a positional misalignment determination unit 203, an abnormality detection unit 204, a data identification unit 205, and a display control unit 206.

[0084] The reception unit 201 receives, from the image reading apparatus 3, read data obtained by the sensor unit 80 reading the color chart 2. The read data of one color chart 2 includes, for example, read data of the quality evaluation pattern Pl and the position detection pattern P3 as illustrated in FIGs. 8A and 8B and read data of the identification code P2. In this case, the reception unit 201 receives the read data DI in response to first conveyance of the color data obtainer 20 in the X-axis direction, and receives the read data D2 in response to second conveyance of the color data obtainer 20 in the X-axis direction after the color chart 2 is conveyed in the Y-axis direction.

[0085] The storage unit 202 stores the reference data of the quality evaluation pattern Pl included in the color chart 2 in a memory or storage medium, such as the auxiliary memory 605, the recording media 606, or the DVD 613. When a plurality of color charts 2 are used, reference data associated with identification information of each of the plurality of color charts 2 is stored together with the identification information. For example, a user or the information processing apparatus 4 downloads the reference data from a data server, or reads the reference data from a recording medium provided together with the color chart 2, so that the reference data is stored in the memory or the like. The information processing apparatus 4 may directly refer to the reference data downloaded from the data server without using the storage unit 202.

[0086] The positional misalignment determination unit 203 determines a misalignment of the read position of the read data received by the reception unit 201. For example, when the read data has no misalignment as illustrated in FIG. 8A, the positional misalignment determination unit 203 obtains a misalignment amount of 0 as the determination result. When the read data is misaligned by AL as illustrated in FIG. 8B, the positional misalignment determination unit203 obtains a misalignment amount of AL and a direction of the misalignment as the determination result.

[0087] The abnormality detection unit 204 uses the read data and the reference data of the quality evaluation pattern Pl and the determination result obtained by the positional misalignment determination unit 203 to detect an abnormality of the sensor unit 80. Specifically, the abnormality detection unit 204 uses the determination result of the positional misalignment to align the positions of the read data and the reference data of the quality evaluation pattern Pl. The abnormality detection unit 204 calculates a difference between the read data and the reference data that correspond to the same position in the quality evaluation pattern Pl. When the difference is greater than or equal to a predetermined threshold value, the abnormality detection unit 204 determines that an abnormality has occurred.

[0088] The process for detecting an abnormality is performed for each sensor of the sensor unit 80. Thus, the difference data above is calculated based on a difference between the read data obtained at a position of a sensor subjected to abnormality detection in the quality evaluation pattern Pl and the reference data corresponding to that position.The predetermined threshold value is, for example, a value set in advance by experiments at a production facility. One threshold value may be set for the sensor unit 80, or different threshold values may be set for different sensors. The threshold value may be dynamically changed in accordance with, for example, the use state of the image reading apparatus 3.

[0089] The data identification unit 205 decodes the read data of the identification code P2 into the identification information, and identifies the reference data corresponding to the quality evaluation pattern Pl by using the decoded identification information.

[0090] The display control unit 206 displays information on a display screen of a display device such as the display 608. When the abnormality detection unit 204 has detected an abnormality for a certain sensor, the display control unit 206 displays, on the display screen, information indicating that the sensor has an abnormality. Specifically, the display control unit 206 displays, on the display screen, information about the sensor for which the abnormality has been detected (such as information about the number or position of the sensor, or information about the color or amount of the calculated difference).

[0091] FIG. 10 is a flowchart illustrating an example of a processing procedure for detecting an abnormality of the sensor unit 80 according to the present embodiment. In step S10, the reception unit 201 receives the read data of the color chart 2. In step S 11, the positional misalignment determination unit 203 determines a misalignment of the read position of the read data.

[0092] In step SI 2, the abnormality detection unit 204 obtains the reference data from the memory or the like, by using the decoded identification information obtained by the data identification unit 205. The data obtained at this time is the reference data for the position that corresponds to the position of the read data in the quality evaluation pattern Pl and is aligned using the determination result of the positional misalignment determination unit 203. When a plurality of color charts 2 are present, the identification information of the quality evaluation pattern Pl is decoded by using the read data of the identification code P2 of the color chart 2, and the reference data associated with the decoded identification information is obtained from the memory or the like.

[0093] In step S13, the information processing apparatus 4 sets an initial value of n (where n = 1, 2, ..., N) to 1. The information processing apparatus 4 performs steps S14 to S18 for each of the sensors (1st to N-th sensors). Note that N denotes a natural number.

[0094] In step S14, the abnormality detection unit 204 calculates a difference between the read data (read data of the n-th sensor) at the position of the n-th sensor in the quality evaluation pattern Pl and the reference data corresponding to that position. When the difference is greater than or equal to the predetermined threshold value (step SI 5: Yes), the user is notified that the n-th sensor has an abnormality in step SI 6. Specifically, the display control unit 206 displays information about the sensor for which the abnormality has been detected on the display screen. On the other hand, when the difference is less than the predetermined threshold value (step S15: No), the process proceeds to step SI 7.

[0095] In step SI 7, the abnormality detection unit 204 increments n by 1. When n is less than or equal to N (step SI 8: No), the process returns to step S14 and the abnormality detection process is repeated. On the other hand, when n is greater than N (step SI 8: Yes), the abnormality detection process ends.

[0096] As described above, in the present embodiment, the color patch having a larger dimension than the read range of the sensor unit is used. The read data and the reference data are aligned based on the determination result of the positional misalignment. This allows an abnormality of the image reading apparatus to be appropriately detected even when the quality evaluation pattern has an in-plane unevenness.

[0097] Second EmbodimentIn the first embodiment, a long-term abnormality, such as deterioration over time, that occurs in the sensor unit 80 is detected using the difference of the read data from the reference data. An abnormality that occurs in a short time is successfully detected by using read data(iteratively read data) obtained by repeatedly reading the color chart 2 in a short time. FIG. 11 is a flowchart illustrating an example of a processing procedure for detecting an abnormality of the sensor unit 80 according to the present embodiment. Differences from the first embodiment are that a threshold value and a standard deviation for use in detecting an abnormality are calculated from the iteratively read data of at least part of the color chart 2, and an abnormality is detected using the threshold value and the standard deviation. Since the other functional configuration and operation are substantially the same as those of the first embodiment, a detailed description thereof is omitted.

[0098] In step S20, the reception unit 201 receives the iteratively read data of at least part of the color chart 2. In step S21, the abnormality detection unit 204 obtains the iteratively read data from the reception unit 201. The iteratively read data is, for example, read data obtained by reading part of the color chart 2 iteratively at intervals of 5 seconds ten times with the position of the sensor unit 80 being fixed. Thus, the color of the read-target color patch is one color. Note that other values may be used for the intervals of the iterations and the number of times of iterations. The sensor unit 80 may be iteratively conveyed and stopped to perform iterative reading when the sensor unit 80 is stopped. In this manner, the entirety or part of the color chart 2 may be read, and iteratively read data generated for each of the plurality of colors may be used in abnormality detection.

[0099] In step S22, the information processing apparatus 4 sets an initial value of n (where n = 1, 2, ..., N) to 1. The information processing apparatus 4 performs steps S23 to S28 for each of the sensors (1st to N-th sensors). Note that N denotes a natural number. When the iteratively read data of the plurality of colors is used, the information processing apparatus 4 may perform steps S23 to S28 for each of the colors and performs abnormality detection for each of the colors.

[0100] In step S23, the abnormality detection unit 204 calculates a threshold value from the iteratively read data of the n-the sensor. In step S24, the abnormality detection unit 204 calculates a standard deviation. For example, the threshold value is calculated as an average value of the iteratively read data. When the calculated standard deviation is greater than or equal to the threshold value (step S25: Yes), the user is notified that the n-th sensor has an abnormality in step S26.On the other hand, when the standard deviation is less than the threshold value (step S25: No), the process proceeds to step S27.

[0101] In step S27, the abnormality detection unit 204 increments n by 1. When n is less than or equal to N (step S28: No), the process returns to step S23 and the abnormality detectionprocess is repeated. On the other hand, when n is greater than N (step S28: Yes), the abnormality detection process ends.

[0102] A method for detecting an abnormality of a sensor using the iteratively read data is not limited to the above method. For example, a maximum value of difference values between the average value of the iteratively read data and each read data may be calculated. When the calculated maximum value is greater than or equal to a times the standard deviation, the abnormality detection unit 204 may determine that an abnormality has been detected. In this case, a is a predetermined coefficient, and is, for example, a value set in advance by experiments at a production facility. One coefficient value may be set for the sensor unit 80, or different coefficient values may be set for different sensors. The coefficient value may be dynamically changed in accordance with, for example, the use state of the image reading apparatus 3.

[0103] The iteratively read data may be obtained by reading a white reference plate which is used for calibration of the image reading apparatus 3, instead of the color chart 2. The white reference plate often comes with the image reading apparatus. The use of the white reference plate omits the preparation of the color chart.

[0104] The information processing apparatus 4 may selectively perform the process for detecting an abnormality (first abnormality detection process) described in the first embodiment and the process for detecting an abnormality (second abnormality detection process) described in the present embodiment. In this case, the user can selectively perform the first abnormality detection process alone, the second abnormality detection process alone, or the two abnormality detection processes consecutively, in accordance with the use state of the image reading apparatus 3.

[0105] As described above, in the present embodiment, abnormality detection is performed for a sensor by using the iteratively read data. This allows an abnormality of the image reading apparatus to be appropriately detected even when the quality evaluation pattern has an inplane unevenness.

[0106] Third EmbodimentThe color chart 2 is more prone to quality deterioration than a ceramic tile used in regular calibration. Thus, it is desirable that the user be notified of the replacement timing of the color chart 2. In the present embodiment, the information processing apparatus 4 determines the replacement timing of the color chart 2 by using information about the timing (print timing) when the color chart 2 was printed, and notifies the user of information about the replacement timing. FIG. 12 is a block diagram illustrating a functional configuration of the informationprocessing apparatus 4 according to the present embodiment. Differences from the first embodiment are that the information processing apparatus 4 further includes a replacement timing determination unit 207 and the display control unit 206 notifies the user of the replacement timing of the color chart 2. Since the other functional configuration and operation are substantially the same as those of the first embodiment, a detailed description thereof is omitted.

[0107] The identification code P2 of the color chart 2 can include the information about the print timing of the color chart 2. For example, among numerals obtained by converting the color code information into numerical values, four upper digits are assigned for the year and the month and the rest of the numerals are assigned for the identification information. For example, the four digits of numerals correspond to two lower digits of the year and two digits representing the month. In this case, the number of colors of the color patches of the identification code P2 is set to 10 to allow the colors to be replaced with the numerical values of 0 to 9, which represent the year and month. Note that the number of color patches may be increased so that numerals of six digits or eight digits are assigned for the information about the print timing by adding the numerals indicating the date or the date and time.

[0108] The replacement timing determination unit 207 decodes the read data of the identification code P2 obtained from the reception unit 201 into the information about the print timing, and determines the replacement timing of the color chart 2 by using the information about the print timing. The display control unit 206 displays, on the display screen, the information about the determined replacement timing of the color chart 2. The information about the replacement timing is information about the year and month that is after the print timing by a predetermined period of time, or information prompting the replacement within a predetermined period of time from the current time, for example. The predetermined period of time is, for example, a value set in advance by experiments at a production facility. The predetermined period of time may be dynamically changed in accordance with, for example, the use state of the color chart 2, such as the number of times the color chart 2 has been read.

[0109] When a plurality of color charts 2 are used, the print timing of each of the color charts 2 may be managed using identification information of the color chart 2 in a data server at a production facility of the image reading apparatus, for example. In this case, the replacement timing determination unit 207 makes an inquiry about the print timing of each color chart 2 to the data server, and determines the replacement timing, based on the information about the print timing obtained from the data server. The information about the print timing may be stored together with the identification information in the memory of the information processing apparatus 4, for example. In this case, the replacement timing determination unit 207 determines the replacement timing, based on the information about the print timingobtained from the memory. The information managed in the data server or the memory of the information processing apparatus 4 may be the information about the replacement timing of each color chart 2.

[0110] As described above, in the present embodiment, the user is notified of the replacement timing of the color chart by using the information about the print timing and the information about the replacement timing. This can stop the continuous use of the deteriorated color chart and allows an abnormality of the image reading apparatus to be appropriately detected.

[0111] As described above, according to the first to third embodiments, an abnormality of the image reading apparatus can be detected at a convenient timing for the user in the user's use environment (without sending the image reading apparatus to the production facility or the like). Thus, the user can stop using the image reading apparatus in which the abnormality is left unfixed, appropriately take measures such as adjusting or fixing the image reading apparatus, and operate the image reading apparatus in an abnormality-free state.

[0112] The present invention can be implemented in any convenient form, for example using dedicated hardware, or a mixture of dedicated hardware and software. The present invention may be implemented as computer software implemented by one or more networked processing apparatuses. The processing apparatuses include any suitably programmed apparatuses such as a general purpose computer, a personal digital assistant, a Wireless Application Protocol (WAP) or third-generation (3G)-compliant mobile telephone, and so on. Since the present invention can be implemented as software, each and every aspect of the present invention thus encompasses computer software implementable on a programmable device. The computer software can be provided to the programmable device using any conventional carrier medium (carrier means). The carrier medium includes a transient carrier medium such as an electrical, optical, microwave, acoustic or radio frequency signal carrying the computer code. An example of such a transient medium is a Transmission Control Protocol / Internet Protocol (TCP / IP) signal carrying computer code over an IP network, such as the Internet. The carrier medium may also include a storage medium for storing processor readable code such as a floppy disk, a hard disk, a compact disc read-only memory (CD- ROM), a magnetic tape device, or a solid state memory device.

[0113] The functionality of the elements disclosed herein may be implemented using circuitry or processing circuitry which includes general purpose processors, special purpose processors, integrated circuits, application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), and / or combinations thereof which are configured or programmed, using one or more programs stored in one or more memories, to perform the disclosed functionality. Processors are considered processing circuitry or circuitry as they include transistors andother circuitry therein. In the disclosure, the circuitry, units, or means are hardware that carry out or are programmed to perform the recited functionality. The hardware may be any hardware disclosed herein which is programmed or configured to carry out the recited functionality.There is a memory that stores a computer program which includes computer instructions. These computer instructions provide the logic and routines that enable the hardware (e.g., processing circuitry or circuitry) to perform the method disclosed herein. This computer program can be implemented in known formats as a computer-readable storage medium, a computer program product, a memory device, a record medium such as a CD-ROM or DVD, and / or the memory of an FPGA or ASIC.

[0114] For example, the program to be executed by the information processing apparatus 4 in the first to third embodiments (hereinafter, referred to as "embodiments") is recorded as a file of an installable format or an executable format on a computer-readable recording medium such as a CR-ROM, a flexible disk (FD), a compact disc recordable (CD-R), or a DVD.

[0115] The program to be executed by the information processing apparatus 4 in the embodiments may be stored in a computer connected to a network such as the Internet, and downloaded and thus provided through the network. The program to be executed by the information processing apparatus 4 in the embodiments may be provided or distributed via a network such as the Internet. The program to be executed by the information processing apparatus 4 in the embodiments may be preinstalled in the ROM or the like and thus provided.

[0116] The above-described embodiments are illustrative and do not limit the present invention. Thus, numerous additional modifications and variations are possible in light of the above teachings. For example, elements and / or features of different illustrative embodiments may be combined with each other and / or substituted for each other within the scope of the present invention. Any one of the above-described operations may be performed in various other ways, for example, in an order different from the one described above.

[0117] The aspects of the present disclosure are as follows, for example.According to Aspect 1, an information processing apparatus includes a reception unit, a storage unit, a positional misalignment determination unit, and an abnormality detection unit. The reception unit receives read data obtained by a sensor unit of an image reading apparatus reading a color chart. The storage unit stores reference data of a quality evaluation pattern included in the color chart. The positional misalignment determination unit determines a misalignment of a read position of the read data. The abnormality detection unit detects an abnormality of the sensor unit. The abnormality detection unit calculates a difference between the read data and the reference data that correspond to a same position in the qualityevaluation pattern by using a determination result obtained by the positional misalignment determination unit, and detects the abnormality based on whether the difference is greater than or equal to a predetermined threshold value.According to Aspect 2, the information processing apparatus of Aspect 1 further includes a data identification unit. The data identification unit identifies the reference data. The color chart includes an identification code corresponding to the quality evaluation pattern, and a positional misalignment determination pattern for use in determining the misalignment of the read position. The positional misalignment determination unit determines the misalignment of the read position by using read data of the positional misalignment determination pattern. The data identification unit identifies the reference data by using read data of the identification code.According to Aspect 3, in the information processing apparatus of Aspect 1 or 2, the reference data of the quality evaluation pattern is data generated by measuring the quality evaluation pattern with a reference colorimeter, or data generated by measuring the quality evaluation pattern with the image reading apparatus at shipment of the image reading apparatus.According to Aspect 4, in the information processing apparatus of any one of Aspects 1 to 3, the sensor unit includes a plurality of sensors. The abnormality detection unit detects the abnormality for each of the plurality of sensors.According to Aspect 5, the information processing apparatus of any one of Aspects 1 to 4 further includes a display control unit. The display control unit displays information on a display screen. The display control unit displays, in a case where the abnormality detection unit has detected the abnormality, display information about a sensor for which the abnormality has been detected on the display screen.According to Aspect 6, the information processing apparatus of any one of Aspects 1 to 4 further includes a replacement timing determination unit and a display control unit. The replacement timing determination unit determines a replacement timing of the color chart. The display control unit displays information on a display screen. The display control unit displays information indicating the replacement timing determined by the replacement timing determination unit on the display screen.According to Aspect 7, in the information processing apparatus of any one of Aspects 1 to 6, the reception unit further receives iteratively read data obtained by the sensor unit iteratively reading at least part of the color chart. The abnormality detection unit performs a first abnormality detection process of calculating the difference between the read data and the reference data that correspond to the same position in the quality evaluation pattern by using the determination result obtained by the positional misalignment determination unit, and detecting the abnormality based on whether the difference is greater than or equal to the predetermined threshold value, and a second abnormality detection process of detecting the abnormality by using the iteratively read data.According to Aspect 8, in the information processing apparatus of any one of Aspects 1 to 6, the reception unit further receives iteratively read data obtained by the sensor unit iteratively reading a white reference plate. The abnormality detection unit performs a first abnormality detection process of detecting the abnormality by using the read data, the reference data, and the determination result obtained by the positional misalignment determination unit, and a second abnormality detection process of detecting the abnormality by using the iteratively read data.According to Aspect 9, an information processing method includes: receiving read data obtained by a sensor unit of an image reading apparatus reading a color chart; storing reference data of a quality evaluation pattern included in the color chart; determining a misalignment of a read position of the read data; and detecting an abnormality of the sensor unit. The detecting includes calculating a difference between the read data and the reference data that correspond to a same position in the quality evaluation pattern by using a determination result obtained in the determining, and detecting the abnormality based on whether the difference is greater than or equal to a predetermined threshold value.According to Aspect 10, a program causes a computer to function as reception means, storage means, positional misalignment determination means, and abnormality detection means. The reception means receives read data obtained by a sensor unit of an image reading apparatus reading a color chart. The storage means stores reference data of a quality evaluation pattern included in the color chart. The positional misalignment determination means determines a misalignment of a read position of the read data. The abnormality detection means detects an abnormality of the sensor unit. The abnormality detection means calculates a difference between the read data and the reference data that correspond to a same position in the quality evaluation pattern by using a determination result obtained by the positional misalignment determination means, and detects the abnormality based on whether the difference is greater than or equal to a predetermined threshold value.According to Aspect 11, an information processing system includes an image reading apparatus including a sensor unit to read a color chart and a white reference plate, and the information processing apparatus according to any one of Aspects 1 to 8.

[0118] This patent application is based on and claims priority to Japanese Patent Application No. 2024-056146, filed on March 29, 2024, in the Japan Patent Office, the entire disclosure of which is hereby incorporated by reference herein.[Reference Signs List]

[0119] 1 information processing system3 image reading apparatus4 information processing apparatus 51 white reference platereception unit storage unit positional misalignment determination unit abnormality detection unit data identification unit display control unit replacement timing determination unit

Claims

[CLAIMS]1. An information processing apparatus comprising: a reception unit configured to receive read data obtained by a sensor unit of an image reading apparatus reading a color chart; a storage unit configured to store reference data of a quality evaluation pattern included in the color chart; a positional misalignment determination unit configured to determine a misalignment of a read position of the read data; and an abnormality detection unit configured to detect an abnormality of the sensor unit, wherein the abnormality detection unit is configured to calculate a difference between the read data and the reference data that correspond to a same position in the quality evaluation pattern based on a determination result obtained by the positional misalignment determination unit, and detect the abnormality based on whether the difference is greater than or equal to a threshold value.

2. The information processing apparatus according to claim 1, further comprising: a data identification unit configured to identify the reference data, wherein the color chart includes an identification code corresponding to the quality evaluation pattern, and a positional misalignment determination pattern for use in determining the misalignment of the read position, the positional misalignment determination unit is configured to determine the misalignment of the read position by using read data of the positional misalignment determination pattern, and the data identification unit is configured to identify the reference data by using read data of the identification code.

3. The information processing apparatus according to claim 1 or 2, wherein the reference data of the quality evaluation pattern is data generated by measuring the quality evaluation pattern with a reference colorimeter, or data generated by measuring the quality evaluation pattern with the image reading apparatus at shipment of the image reading apparatus.

4. The information processing apparatus according to any one of claims 1 to 3, wherein the sensor unit includes a plurality of sensors, and the abnormality detection unit is configured to detect the abnormality for each of the plurality of sensors.

5. The information processing apparatus according to claim 4, further comprising: a display control unit configured to display information on a display screen, wherein the display control unit is configured to display, in a case where the abnormality detection unit has detected the abnormality, display information indicating one of the plurality of sensors for which the abnormality has been detected on the display screen.

6. The information processing apparatus according to any one of claims 1 to 4, further comprising: a replacement timing determination unit configured to determine a replacement timing of the color chart; and a display control unit configured to display information on a display screen, wherein the display control unit is configured to display information indicating the replacement timing determined by the replacement timing determination unit on the display screen.

7. The information processing apparatus according to any one of claims 1 to 6, wherein the reception unit is configured to further receive iteratively read data obtained by the sensor unit iteratively reading at least part of the color chart, and the abnormality detection unit is configured to perform a first abnormality detection process of calculating the difference between the read data and the reference data that correspond to the same position in the quality evaluation pattern based on the determination result obtained by the positional misalignment determination unit, and detecting the abnormality based on whether the difference is greater than or equal to the threshold value, and a second abnormality detection process of detecting the abnormality by using the iteratively read data.

8. The information processing apparatus according to any one of claims 1 to 6, wherein the reception unit is configured to further receive iteratively read data obtained by the sensor unit iteratively reading a white reference plate, and the abnormality detection unit is configured to perform a first abnormality detection process of detecting the abnormality by using the read data, the reference data, and the determination result obtained by the positional misalignment determination unit, and a second abnormality detection process of detecting the abnormality by using the iteratively read data.

9. An information processing system comprising: the information processing apparatus according to any one of claims 1 to 8; andan image reading apparatus including the sensor unit to read the color chart and a white reference plate.

10. An information processing method comprising: receiving read data obtained by a sensor unit of an image reading apparatus reading a color chart; storing reference data of a quality evaluation pattern included in the color chart; determining a misalignment of a read position of the read data; and detecting an abnormality of the sensor unit, wherein the detecting includes calculating a difference between the read data and the reference data that correspond to a same position in the quality evaluation pattern based on a determination result obtained in the determining, and detecting the abnormality based on whether the difference is greater than or equal to a predetermined threshold value.

11. A recording medium storing computer readable code for controlling a computer system to execute an information processing method, the information processing method comprising: receiving read data obtained by a sensor unit of an image reading apparatus reading a color chart; storing reference data of a quality evaluation pattern included in the color chart; determining a misalignment of a read position of the read data; and detecting an abnormality of the sensor unit, wherein the detecting includes calculating a difference between the read data and the reference data that correspond to a same position in the quality evaluation pattern based on a determination result obtained in the determining, and detecting the abnormality based on whether the difference is greater than or equal to a predetermined threshold value.

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