Imaging control program and printing system

Abstract

To provide a configuration capable of imaging an appropriate test pattern.SOLUTION: An imaging control program causes a computer to realize a determination function that determines whether an imaging condition is satisfied or not to cause an imaging unit to image an imaging target area including a test pattern, and an imaging control function to acquire a captured image by allowing the imaging unit to image the imaging target area when the imaging condition is satisfied. The determination function is used to repeatedly acquire the amount of change in the relative positional relationship between the imaging unit and the medium. Under the imaging condition, at least a first condition that the imaging target area is included in the angle of view of the imaging unit and a second condition that the acquired amount of change is equal to or less than a reference amount of change are satisfied. The determination function is used to whether the first condition is satisfied or not on the basis of frames repeatedly acquired from the imaging unit, and determines whether the second condition is satisfied or not on the basis of the acquired amount of change.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to an imaging control program for imaging a medium having a test pattern for adjusting print characteristics, and a printing system. [Background technology]

[0002] 2. Description of the Related Art Test patterns for adjusting the printing characteristics of printing devices such as inkjet printers are read by scanners. Patent Document 1 discloses a print correction method that generates print correction data by photographing a print correction test pattern printed by a printer with a digital camera. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-121486 Summary of the Invention [Problem to be solved by the invention]

[0004] Some printing devices do not have a scanner, and even if they do, some users do not know how to adjust the printing characteristics. However, if a user captures a test pattern using a handheld device with a camera, the test pattern may not be captured properly. [Means for solving the problem]

[0005] An imaging control program according to the present invention is an imaging control program for imaging a medium having a test pattern for adjusting printing characteristics of a printing device equipped with a recording head, the program comprising: a determination function for determining whether or not an imaging condition for causing an imaging unit to capture an image of an imaging target area including the test pattern is satisfied; an imaging control function of acquiring a captured image by causing the imaging unit to capture an image of the imaging target area when the imaging condition is satisfied; the determining function repeatedly acquires a change in the relative positional relationship between the imaging unit and the medium; the imaging condition is a condition in which at least a first condition that the imaging target area is included in an angle of view of the imaging unit and a second condition that the acquired change amount is equal to or less than a reference change amount are satisfied; The judgment function has a configuration in which it judges whether the first condition is satisfied based on frames repeatedly acquired from the imaging unit, and judges whether the second condition is satisfied based on the acquired amount of change.

[0006] A printing system of the present invention is a printing system including a printing device including a recording head, and an information terminal that captures an image of a medium having a test pattern for adjusting the printing characteristics of the printing device, The information terminal An imaging unit; a control unit including a memory for storing an image obtained from the imaging unit, and causing the imaging unit to capture an image of an imaging target area including the test pattern; the control unit repeatedly acquires a change in the relative positional relationship between the imaging unit and the medium, determines whether or not an imaging condition for causing the imaging unit to capture an image of the imaging target area is satisfied, and acquires the captured image by causing the imaging unit to capture an image of the imaging target area when the imaging condition is satisfied; the imaging condition is a condition in which at least a first condition that the imaging target area is included in an angle of view of the imaging unit and a second condition that the acquired change amount is equal to or less than a reference change amount are satisfied; The control unit has an aspect in which it determines whether the first condition is satisfied based on frames repeatedly acquired from the imaging unit, and determines whether the second condition is satisfied based on the acquired amount of change. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram schematically illustrating an example of a printing system. [Figure 2] FIG. 1 is a diagram schematically illustrating an example of the configuration of a printing system. [Figure 3] FIG. 10 is a diagram schematically illustrating an example of a medium having a test pattern. [Figure 4] FIG. 10 is a diagram schematically illustrating an example of the operation of an information terminal during imaging. [Figure 5] 10 is a flowchart schematically illustrating an example of an imaging control process. [Figure 6] 5A and 5B are diagrams illustrating examples of whether a first condition is satisfied in which an imaging target area is included in the angle of view of an imaging unit. [Figure 7] 10A and 10B are diagrams illustrating examples of whether or not a second condition, that is, the amount of change in the relative positional relationship between the imaging unit and the medium is equal to or less than a reference amount of change, is satisfied. [Figure 8] 10A and 10B are diagrams illustrating examples of whether or not a third condition, that is, the imaging unit is within a predetermined range of direct facing relative to the imaging target area, is satisfied. [Figure 9] FIG. 10 is a diagram schematically illustrating an example of whether a fourth condition, that is, the distortion amount of a test pattern included in a frame is equal to or less than a reference distortion amount, is satisfied. [Figure 10] FIG. 10 is a diagram schematically showing an example of whether a fifth condition, that is, the distance between the imaging unit and the medium is equal to or less than a reference distance, is satisfied. [Figure 11] 11A and 11B are diagrams schematically showing examples of whether or not the sixth condition, that is, the brightness amount of the background color of the medium is equal to or greater than the reference brightness amount, is satisfied. [Figure 12] FIG. 10 is a diagram schematically showing an example of criteria for determining imaging conditions. [Figure 13] 5A to 5C are diagrams illustrating examples of adjustment of printing characteristics. [Figure 14] 10 is a flowchart illustrating an example of continuous shooting control processing. DETAILED DESCRIPTION OF THE INVENTION

[0008] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The following describes embodiments of the present invention. Of course, the following embodiments are merely examples of the present invention, and not all of the features shown in the embodiments are necessarily essential to the solution of the invention.

[0009] (1) Summary of the aspects included in the present invention: First, an overview of the embodiments included in the present invention will be described with reference to the examples shown in Figures 1 to 14. Note that the figures in this application are diagrams showing schematic examples, and the magnifications in each direction shown in these figures may differ, and the figures may not be consistent with each other. Of course, each element of the present embodiment is not limited to the specific example indicated by the symbol. In the "Outline of the embodiments included in the present invention," the words in parentheses indicate supplementary explanations for the immediately preceding words.

[0010] [Aspect 1] 2, 5, etc., an imaging control program PR0 according to one embodiment is an imaging control program PR0 for imaging a medium ME0 having a test pattern TP0 for adjusting the printing characteristics of a printing device 2 equipped with a recording head 220, and causes a computer (e.g., information terminal 1) to implement a determination function FU1 and an imaging control function FU2. The determination function FU1 determines whether imaging conditions (see, e.g., FIG. 12) for causing the imaging unit 120 to capture an imaging target area AR0 including the test pattern TP0 are met. The imaging control function FU2, triggered by the imaging conditions being met, causes the imaging unit 120 to capture an imaging target area AR0, thereby acquiring a captured image IM0. The determination function FU1 repeatedly acquires a change amount V in the relative positional relationship between the imaging unit 120 and the medium ME0. The imaging conditions are conditions that at least satisfy a first condition (see, for example, FIG. 6) that the imaging target area AR0 is included in the angle of view FA of the imaging unit 120, and a second condition (see, for example, FIG. 7) that the acquired amount of change V is equal to or less than a reference amount of change (e.g., a threshold value THV). The determination function FU1 determines whether the first condition is satisfied based on frames FR0 repeatedly acquired from the imaging unit 120, and determines whether the second condition is satisfied based on the acquired amount of change V.

[0011] When an information terminal 1 separate from the printing device 2 is used to capture the image of the test pattern TP0, the captured image IM0 may be blurred or may be captured in an unintended range. If the captured image range is unintended or blurred, the position and color of the test pattern TP0 will not be captured correctly, and as a result, the test pattern TP0 will not function properly. In the above-described aspect 1, imaging is triggered by at least satisfying the following conditions: the imaging target area AR0 including the test pattern TP0 is included in the angle of view FA, and the amount of change V in the relative positional relationship between the imaging unit 120 and the medium ME0 is small. This results in an appropriate imaging range and a captured image IM0 with little blur. This allows an appropriate captured image of the test pattern to be used to adjust printing characteristics. Therefore, the above-described aspect 1 can provide an imaging control program capable of capturing an appropriate test pattern. As a result, memory congestion caused by unnecessary captured images can be reduced. In addition, when it is necessary to press or touch a mechanical or electrical button on the information terminal 1 to release the shutter, there is a possibility that camera shake or the like may occur due to button operation. By capturing an image when the imaging conditions are met as a trigger, camera shake or the like due to button operation can be reduced.

[0012] There are various examples of the above-described aspects. Examples of printing characteristics include the density of the printed image, the landing position of the droplets, the transport amount of the medium, and the droplet ejection state of each nozzle. Examples of test patterns include density patterns for adjusting the density of the printed image, Bi-d adjustment patterns for performing Bi-d adjustment (bidirectional adjustment) to align the landing position of droplets on the forward and return paths, transport amount adjustment patterns for adjusting the transport amount of the medium on which the printed image is formed, and nozzle check patterns that show the droplet ejection status of each nozzle of the recording head. Examples of the imaging target area include the entire medium, an area partitioned by a plurality of position detection patterns, and the like. Acquiring a captured image may involve storing the captured image obtained from the imaging unit in memory, or may involve controlling a DMA (Direct Memory Access) controller to store the captured image in memory, etc. Storing in memory includes storing in RAM (Random Access Memory), storing in non-volatile memory, etc. A frame refers to an image represented by a signal output from an imaging unit for each frame period. Examples of the amount of change in the relative positional relationship between the imaging unit and the medium include the amount of movement of the medium between frames, the speed detected by a speed sensor, and the acceleration detected by an acceleration sensor. The angle of view means the imaging range. In this application, the terms "first", "second", etc. are terms for distinguishing between elements among a plurality of elements having similarities, and do not imply any order. Of course, the above remarks also apply to the following aspects.

[0013] [Aspect 2] The imaging condition may be a condition in which at least the first condition, the second condition, and a third condition (see, for example, FIG. 8) that the imaging unit 120 is within a predetermined range facing the imaging target area AR0 are satisfied. The determination function FU1 may determine whether the third condition is satisfied based on the shape of the imaging target area AR0 included in the frame FR0. If the imaging unit 120 is not within the range directly facing the test pattern TP0, the resolution of the test pattern TP0 will differ between the sides closer to and farther from the imaging unit 120, and the resulting adjustment values ​​may differ between the sides closer to and farther from the imaging unit 120. In the above-described second aspect, imaging is triggered by conditions including the imaging unit 120 being within the range directly facing the test pattern TP0, so a more appropriate captured image of the test pattern can be used to adjust the printing characteristics. Therefore, the above-described second aspect can provide an imaging control program that can capture a more appropriate test pattern.

[0014] [Aspect 3] The imaging condition may be a condition in which at least the first condition, the second condition, and a fourth condition (see, for example, FIG. 9) in which a distortion amount DS indicating distortion of the test pattern TP0 included in the frame FR0 is equal to or less than a reference distortion amount (for example, a threshold value THDS) are satisfied. The determination function FU1 may determine whether the fourth condition is satisfied based on the shape of the test pattern TP0 included in the frame FR0. If the test pattern TP0 is significantly distorted, the adjustment value may change depending on the position of the test pattern TP0. In the above-described third aspect, imaging is triggered by conditions including a small distortion amount DS of the test pattern TP0 included in the frame FR0, so a more appropriate captured image of the test pattern can be used to adjust the printing characteristics. Therefore, the above-described third aspect can provide an imaging control program that can capture a more appropriate test pattern.

[0015] [Aspect 4] The determination function FU1 may repeatedly detect a distance D corresponding to the distance between the imaging unit 120 and the medium ME0. The imaging condition may be a condition in which at least the first condition, the second condition, and a fifth condition (see, for example, FIG. 10) in which the distance D is equal to or less than a reference distance (for example, a threshold THD) are satisfied. The determination function FU1 may determine whether the fifth condition is satisfied based on the detected distance D. If the imaging unit 120 is too far from the medium ME0, the resolution of the captured test pattern TP0 will be low, resulting in a large error in the adjustment value. In the above-described embodiment 4, imaging is triggered by conditions including the distance D between the imaging unit 120 and the medium ME0 being equal to or less than the reference distance (THD), so a more appropriate captured image of the test pattern can be used to adjust the printing characteristics. Therefore, the above-described embodiment 4 can provide an imaging control program that can capture a more appropriate test pattern.

[0016] Here, examples of the spacing amount include the distance from the imaging unit to the medium, such as the distance detected by a distance measuring sensor, and an amount using the ratio of the area of ​​the image capture region in the frame to the area of ​​the frame. This statement also applies to the following aspects.

[0017] [Aspect 5] The determination function FU1 may acquire a brightness amount L0 indicating the brightness L of the background color of the medium ME0 based on the frame FR0. The imaging condition may be a condition in which at least the first condition, the second condition, and a sixth condition (see, for example, FIGS. 11A and 11B) in which the brightness amount L0 is equal to or greater than a reference brightness amount (e.g., a threshold value THL) are satisfied. The determination function FU1 may determine whether the sixth condition is satisfied based on the acquired brightness amount L0. For example, if the captured image IM0 is dark due to the influence of a shadow or the like, the density of the captured test pattern TP0 will be high, and the color of the test pattern TP0 will not be captured correctly. In the above-mentioned aspect 5, the image is captured using conditions including the brightness L0 of the background color of the medium ME0 being equal to or greater than the reference brightness (THL), so a more appropriate captured test pattern image can be used to adjust the printing characteristics. Therefore, the above-mentioned aspect 5 can provide an imaging control program that can capture a more appropriate test pattern.

[0018] [Aspect 6] The imaging conditions may be conditions that at least satisfy the first condition, the second condition, a third condition that the imaging unit 120 is within a predetermined range facing the imaging target area AR0, a fourth condition that a distortion amount DS indicating distortion of the test pattern TP0 included in the frame FR0 is less than or equal to a reference distortion amount (e.g., a threshold value THDS), a fifth condition that the spacing amount D is less than or equal to a reference spacing amount (e.g., a threshold value THD), and a sixth condition that the brightness amount L0 is greater than or equal to a reference brightness amount (e.g., a threshold value THL). The judgment function FU1 may determine whether the third condition is met based on the shape of the imaging target area AR0 included in the frame FR0, may determine whether the fourth condition is met based on the shape of the test pattern TP0 included in the frame FR0, may repeatedly detect a spacing amount D corresponding to the distance between the imaging unit 120 and the medium ME0 and determine whether the fifth condition is met based on the detected spacing amount D, may acquire a brightness amount L0 indicating the brightness L of the background color of the medium ME0 based on the frame FR0, and may determine whether the sixth condition is met based on the acquired brightness amount L0. By combining a plurality of conditions, it is possible to provide an imaging control program that can capture an image of a more appropriate test pattern.

[0019] [Aspect 7] 14, the imaging control function FU2 may receive an input of the number of times Nt to repeat imaging of the imaging target area AR0. The imaging control function FU2 may cause the imaging unit 120 to repeatedly image the imaging target area AR0 the number of times Nt when the imaging condition is satisfied. In the above cases, since appropriate test pattern images can be obtained multiple times, the printing characteristics can be adjusted more appropriately.

[0020] [Aspect 8] As illustrated in FIG. 5, the imaging control program PR0 may further cause the computer (1) to implement a guidance function FU3 that outputs guidance for satisfying a condition when any of the multiple conditions included in the imaging conditions is not satisfied. In the above cases, guidance for satisfying the imaging conditions is output, allowing for smooth imaging of the medium ME0. In particular, guidance for satisfying unsatisfied conditions among the multiple conditions included in the imaging conditions is output, preventing the user from moving the imaging device unnecessarily to satisfy conditions that have already been satisfied. As a result, the time required for imaging can be shortened.

[0021] [Aspect 9] 1 and 2, a printing system SY1 according to one embodiment includes a printing device 2 including a recording head 220 and an information terminal 1 that captures an image of a medium ME0 having a test pattern TP0 for adjusting the printing characteristics of the printing device 2. The information terminal 1 includes an imaging unit 120 and a control unit 110 that includes a memory (e.g., RAM 113) for storing a captured image IM0 obtained from the imaging unit 120 and causes the imaging unit 120 to capture an image of an imaging target area AR0 that includes the test pattern TP0. The control unit 110 repeatedly acquires a change V in the relative positional relationship between the imaging unit 120 and the medium ME0, determines whether an imaging condition for causing the imaging unit 120 to capture the imaging target area AR0 is satisfied, and, when the imaging condition is satisfied, causes the imaging unit 120 to capture the imaging target area AR0, thereby acquiring the captured image IM0. The imaging conditions are conditions that at least satisfy a first condition that the imaging target area AR0 is included in the angle of view FA of the imaging unit 120 and a second condition that the acquired amount of change V is equal to or less than a reference amount of change (THV). The control unit 110 determines whether the first condition is satisfied based on frames FR0 repeatedly acquired from the imaging unit 120, and determines whether the second condition is satisfied based on the acquired amount of change V. The above-mentioned ninth aspect can provide a printing system capable of capturing an appropriate test pattern.

[0022] Furthermore, the above-described aspects are applicable to a computer-readable non-transitory medium on which the above-described imaging control program is recorded, the above-described information terminal, a control method for the information terminal, a printing method implemented by the above-described printing system, a control program for the above-described printing system, a computer-readable non-transitory medium on which the control program is recorded, etc. Any of the above-described devices may be composed of multiple distributed parts.

[0023] (2) Example of imaging control program: Fig. 1 schematically illustrates a printing system SY1 including an information terminal 1 and a printing device 2. Fig. 2 schematically illustrates the configuration of the printing system SY1. Fig. 3 schematically illustrates a medium ME0 having a test pattern TP0. Examples of the information terminal 1 include a mobile phone such as a smartphone, a tablet terminal, etc. The information terminal 1 may be composed of multiple devices separated so that they can communicate with each other, or may be a stationary device with an imaging unit connected to it so that its position can be changed. The printing device 2 is assumed to be an inkjet printer equipped with a recording head 220 capable of ejecting droplets 280. Of course, the printing device 2 may also be a thermal printer (including a thermal transfer printer) equipped with a thermal head as a recording head, an electrophotographic printer (e.g., a laser printer) equipped with a recording head that deposits toner on the medium ME0, a three-dimensional printer, etc. The printing device 2 may be composed of multiple devices separated so that they can communicate with each other.

[0024] The printing device 2 can form a print image PI0 on a medium ME0, including a test pattern TP0 for adjusting the printing characteristics of the printing device 2. A user US1 can adjust the printing characteristics of the printing device 2 by capturing the test pattern TP0 with an information terminal 1 equipped with an imaging unit 120. When the user US1 captures the test pattern TP0 while holding the information terminal 1 in his or her hand, there is a possibility that a portion of the test pattern TP0 falls outside the field of view (i.e., the imaging range) of the imaging unit 120, camera shake may occur, the test pattern TP0 may be tilted, the test pattern TP0 may be too far from the imaging unit 120, or the imaging environment may be too dark. Furthermore, if a button on the information terminal 1 must be pressed to release the shutter, camera shake or other issues may occur due to the button operation. Therefore, the imaging control program PR0 shown in FIG. 2 automatically causes the imaging unit 120 to capture an image when imaging conditions are met, thereby enabling the information terminal 1 to capture an appropriate test pattern TP0. The information terminal 1 executing the imaging control program PR0 can be said to implement an auto-shutter system. Even if the information terminal 1 is not portable but is a stationary device, the imaging control program PR0 may be executed in cases where shaking occurs or the relative positional relationship with the test pattern TP0 changes.

[0025] The communication I / F (interface) 117 of the information terminal 1 is capable of communicating with the communication I / F 230 of the printing device 2. The information terminal 1 is capable of transmitting adjustment values ​​for printing characteristics and the like to the printing device 2 via the communication I / Fs 117 and 230. Upon receiving the adjustment values, the printing device 2 stores the adjustment values ​​and adjusts the printing characteristics based on the adjustment values. Communication via the communication I / Fs 117 and 230 may be wireless communication in accordance with wireless LAN (Local Area Network) standards or the like, wired communication, or even network communication such as the Internet.

[0026] 2 includes a control unit 110, a storage unit 114, an operation unit 115, a display unit 116, a communication I / F 117, and an imaging unit 120. The information terminal 1 may also include sensors SS1 and SS2 connected to the control unit 110. The control unit 110 includes a CPU (Central Processing Unit) 111, which is a processor, a ROM (Read Only Memory) 112, and a RAM (Random Access Memory) 113. The RAM 113 is an example of a memory for storing a captured image IM0 obtained from the imaging unit 120.

[0027] The storage unit 114 stores an imaging control program PR0 and the like for imaging a medium ME0 having a test pattern TP0. A nonvolatile semiconductor memory such as a flash memory can be used for the storage unit 114. The storage unit 114 may be removably attached to the main body of the information terminal 1. The display unit 116 displays a screen corresponding to the display information based on the display information. A liquid crystal display panel or the like can be used for the display unit 116. The operation unit 115 can be a touch panel attached to the surface of the display unit 116, hard keys, or the like. The display unit 116 displays a screen corresponding to the display information based on the display information.

[0028] The imaging control program PR0 causes the information terminal 1 to realize the determination function FU1, the imaging control function FU2, and the guidance function FU3. The CPU 111 performs various processes by appropriately reading information stored in the storage unit 114 into the RAM 113 and executing the read program. The CPU 111 performs processes corresponding to the above-mentioned functions (FU1 to FU3) by executing the imaging control program PR0 read into the RAM 113. The information terminal 1 that executes the imaging control program PR0 performs a determination step corresponding to the determination function FU1, an imaging control step corresponding to the imaging control function FU2, and a guidance step corresponding to the guidance function FU3. The computer-readable medium that stores the imaging control program PR0 that causes a computer to realize the above-mentioned functions (FU1 to FU3) is not limited to the storage unit 114, and may be a recording medium external to the information terminal 1.

[0029] The imaging unit 120 includes a lens 121, an AF (autofocus) unit 122, an image sensor 123, and the like. The image sensor 123 converts an image of light incident via the lens 121 and the AF unit 122 into an electrical signal. The image sensor 123 in this specific example outputs digital data corresponding to the electrical signal of each light receiving element. The digital data is stored in the RAM 113 as a frame FR0 or a captured image IM0. The image sensor 123 may be a CMOS (Complementary Metal-Oxide Semiconductor) image sensor, a CCD (Charge Coupled Devices) image sensor, or the like.

[0030] The sensors SS1 and SS2 can be used to determine whether the imaging conditions are met. For example, the sensor SS1 may be a speed sensor that measures the moving speed of the imaging unit 120, or an acceleration sensor that measures the acceleration of the imaging unit 120. In this case, the magnitude of blur in the captured image IM0 can be detected based on the measurement value from the sensor SS1. The sensor SS2 may also be a distance sensor that measures the distance from the imaging unit 120 to the medium ME0. In this case, the distance from the imaging unit 120 to the medium ME0 can be detected based on the measurement value from the sensor SS2.

[0031] The printing device 2 ejects C (cyan) ink, M (magenta) ink, Y (yellow) ink, and K (black) ink as color materials from a recording head 220 as droplets 280 to form a print image PI0 corresponding to print data. The recording head 220 has multiple nozzles Nc capable of ejecting C ink droplets onto the medium ME0, multiple nozzles Nm capable of ejecting M ink droplets onto the medium ME0, multiple nozzles Ny capable of ejecting Y ink droplets onto the medium ME0, and multiple nozzles Nk capable of ejecting K ink droplets onto the medium ME0. C, M, Y, and K inks are supplied to the recording head 220 from ink cartridges Cc, Cm, Cy, and Ck, respectively. The recording head 220 ejects C, M, Y, and K droplets 280 from the nozzles Nc, Nm, Ny, and Nk, respectively, under the control of the controller 210. When the droplets 280 land on the medium ME0, ink dots are formed on the medium ME0. The printing device 2 also includes a drive unit that changes the relative positional relationship between the recording head 220 and the medium ME0 under the control of the controller 210, such as a transport unit 225 that transports the medium ME0 in a predetermined transport direction. As a result, a printed matter is obtained having a pattern of ink dots on the medium ME0 as a print image PI0. The material of the medium ME0 is not particularly limited, and may be paper, fabric, resin, metal, or the like. The shape of the medium ME0 may be a two-dimensional cut shape, a roll, or a three-dimensional shape.

[0032] The medium ME0 shown in FIG. 3 has a test pattern TP0 including multiple individual patterns TP1 and multiple position detection patterns MK0. The test pattern TP0 may be a density pattern, a Bi-d adjustment pattern, a conveyance distance adjustment pattern, a nozzle check pattern, or the like. Each position detection pattern MK0 is located at a corner C0 of a rectangle on the medium ME0 that includes the test pattern TP0. When the position detection patterns MK0 are located at the four corners of the rectangle, the imaging target area AR0 including the test pattern TP0 becomes a rectangular area on the medium ME0 with each position detection pattern MK0 at its corner C0. In FIG. 3, the rectangular imaging target area AR0 with vertical sides S1 and S2 and horizontal sides S3 and S4 is indicated by a two-dot chain line. The position detection pattern MK0 may be a square-shaped ArUco marker, a triangular pattern, or the like, that has specific geometric characteristics. If there is no position detection pattern MK0 on the medium ME0, the medium ME0 itself becomes the imaging target area AR0. In this case, the medium ME0 is preferably cut like a cut sheet of paper, and is preferably, but not limited to, rectangular.

[0033] Next, an example of the operation of the information terminal 1 when capturing an image will be described with reference to Fig. 4. Normally, capturing an image is triggered by an operation on a shutter button included in the operation unit 115. Frames FR0 constituting the moving image VD0 are transferred from the image sensor 123 of the imaging unit 120 to the RAM 113 of the control unit 110 for each frame period. At this time, the CPU 111 may store the frames FR0 in the RAM 113, or a DMA controller (not shown) may store the frames FR0 in the RAM 113. Each frame FR0 represents a still image for each frame period, but may also contain information indicating a difference from the previous frame. Due to the processing capacity of the information terminal 1, each frame FR0 has a lower resolution than the captured image IM0. It can also be said that the frame FR0 has fewer pixels than the captured image IM0. The control unit 110 controls the AF unit 122 and the like based on the group of frames FR0. The control unit 110 may display each frame FR0 on the display unit 116.

[0034] When the user US1 presses or touches the shutter button, the operation unit 115 accepts the operation, and the operation unit 115 notifies the control unit 110 that the shutter button has been operated. The control unit 110 then issues an image capture instruction IS1 to the image capture unit 120, causing the image capture unit 120 to capture an image. A captured image IM0 generated by this image capture has a higher resolution than the frame FR0, and is stored in the RAM 113. Here again, the CPU 111 may perform the process of storing the captured image IM0 in the RAM 113, or a DMA controller (not shown) may perform the process of storing the captured image IM0 in the RAM 113. When the user US1 performs an operation to save the captured image IM0, the operation unit 115 accepts the operation and notifies the control unit 110 of a save instruction IS2. The control unit 110 then converts the captured image IM0 into a file FL0 format and saves it in the storage unit 114. That is, the storage unit 114 stores the file FL0. Examples of file formats include the JPEG (Joint Photographic Experts Group) format and bitmap format. The control unit 110 may accept settings such as the file format and the resolution of the captured image IM0 included in the file FL0 via the operation unit 115, and save the file FL0 in accordance with the settings in the storage unit 114. The control unit 110 may also automatically generate a file FL0 of the captured image IM0 and store it in the storage unit 114 when the captured image IM0 is stored in the RAM 113.

[0035] However, the button operation for capturing an image may cause camera shake, etc. Therefore, in this example, an image is automatically captured when the image capturing conditions are satisfied.

[0036] (3) Specific examples of imaging control processing: FIG. 5 schematically illustrates an example of the imaging control process performed by the control unit 110. Here, steps S102 to S106 correspond to the determination function FU1, step S108 corresponds to the guidance function FU3, and step S110 corresponds to the imaging control function. Hereinafter, the word "step" may be omitted, and the step code may be shown in parentheses. The imaging control process begins when the control unit 110 receives an instruction to capture an image of the imaging target area AR0 via the operation unit 115. The imaging instruction may be an operation on the imaging instruction area displayed after the imaging control program PR0 is started, an operation on the shutter button, or an operation to start the imaging control program PR0. FIGS. 6 to 12 schematically illustrate examples of each condition included in the imaging conditions.

[0037] When the imaging control process starts, the control unit 110 determines whether a new frame FR0 has been transferred from the image sensor 123 to the RAM 113 (S102). The determination process of S102 is repeated until a new frame FR0 is transferred. The determination process of S102 can also be said to be a process of determining whether a new frame FR0 has been acquired from the imaging unit 120. When a new frame FR0 is transferred, the control unit 110 acquires condition satisfaction determination information for determining whether or not an imaging condition for causing the imaging unit 120 to capture an image of the imaging target area AR0 including the test pattern TP0 has been satisfied (S104). The condition satisfaction determination information includes a change amount V in the relative positional relationship between the imaging unit 120 and the medium ME0, and a distance amount D corresponding to the distance between the imaging unit 120 and the medium ME0. Details of the condition satisfaction determination information will be described later.

[0038] After acquiring the condition satisfaction determination information, the control unit 110 determines whether the image capturing conditions are satisfied based on the frame FR0 and the condition satisfaction determination information (S106). If the image capturing conditions are not satisfied, the control unit 110 outputs guidance for satisfying the unsatisfied conditions (S108) and returns the process to S106. As a result, the processes of S102 to S108 are repeated until the image capturing conditions are satisfied, and the control unit 110 repeatedly acquires the frame FR0 from the image capturing unit 120 and repeatedly acquires the condition satisfaction determination information. The guidance may be output as a display on the display unit 116, or as an audio output to an audio output unit (not shown). The processes of S106 and S108 will be described in detail later.

[0039] When the imaging conditions are satisfied, the control unit 110 acquires the captured image IM0 by causing the imaging unit 120 to capture an image of the imaging target area AR0 (S110). At this time, the CPU 111 may store the captured image IM0 from the image sensor 123 in the RAM 113, or the DMA controller may store the captured image IM0 from the image sensor 123 in the RAM 113. The captured image IM0 has a higher resolution than the frame FR0. As described above, the control unit 110 acquires the captured image IM0 by causing the imaging unit 120 to capture an image of the imaging target area AR0 using the satisfaction of the imaging conditions as a trigger.

[0040] After acquiring the captured image IM0, the control unit 110 determines whether or not to save the captured image IM0 as a file FL0 (S112). For example, when the operation unit 115 accepts an operation to save the captured image IM0, the control unit 110 causes the storage unit 114 to store the captured image IM0 in the format of file FL0 (S114), and ends the imaging control process. That is, the storage unit 114 stores the file FL0. When the operation unit 115 accepts an operation to discard the captured image IM0, the control unit 110 ends the imaging control process without performing the saving process of S114. Furthermore, in S112, the control unit 110 may determine whether the test pattern TP0 included in the captured image IM0 is appropriate for adjusting the printing characteristics. In this case, the control unit 110 may perform the saving process of S114 if it determines that the test pattern TP0 is appropriate, or may return the process to S102 if it determines that the test pattern TP0 is inappropriate. This is because even if the imaging conditions are met, there is a time lag until the actual imaging. Furthermore, the control unit 110 may perform the process of S114 without performing the determination process of S112, so that the storage of the captured image IM0 in RAM 113 is used as a trigger to automatically generate a file FL0 for the captured image IM0 and store it in the storage unit 114.

[0041] Next, the processes in S104 to S108 will be described in detail. 6 schematically shows an example of whether or not a first condition is satisfied, that is, whether the imaging target area AR0 is included in the angle of view FA of the imaging unit 120. Whether or not the first condition is satisfied can be determined by determining whether or not the imaging target area AR0 is completely included in the frame FR0 corresponding to the angle of view FA.

[0042] For example, suppose that medium ME0 has position detection patterns MK0 at the four corners of imaging target area AR0. In this case, control unit 110 can determine that the first condition is met if it can detect position detection patterns MK0 at four locations from frame FR0. Furthermore, control unit 110 can determine that the first condition is not met if it cannot detect even one of the four position detection patterns MK0 from frame FR0. If the medium ME0 does not have a position detection pattern MK0, the medium ME0 itself becomes the imaging target area AR0. If the medium ME0 is rectangular, the control unit 110 can determine that the first condition is met if it can detect multiple edges from the frame FR0 and detect a rectangle surrounded by two edges determined to be vertically oriented and two edges determined to be horizontally oriented. Because the medium ME0 included in the frame FR0 may be tilted, "vertical orientation" includes orientations that deviate from the strict vertical orientation within a predetermined allowable angle range, and "horizontal orientation" includes orientations that deviate from the strict horizontal orientation within a predetermined allowable angle range. Well-known rectangle recognition techniques, such as business card recognition, can be used to recognize the medium ME0 from the frame FR0.

[0043] In this way, the control unit 110 determines whether or not the first condition is satisfied based on the frame FR0 repeatedly acquired from the imaging unit 120. If the first condition is not satisfied, the control unit 110 outputs guidance for satisfying the first condition in S108 shown in Fig. 5. Examples of outputting this guidance include displaying information such as "Please fit the entire test pattern within the screen" or outputting a voice.

[0044] 7 shows a schematic example of whether the second condition, that is, the amount of change V in the relative positional relationship between the image capture unit 120 and the medium ME0 is equal to or less than the threshold value THV, is satisfied. The threshold value THV is an example of a reference amount of change and is a positive value. The control unit 110 repeatedly acquires a frame FR0 from the imaging unit 120. Here, the previously acquired frame FR0 will be referred to as the “previous frame FR1,” and the currently acquired frame FR0 will be referred to as the “current frame FR2.” The control unit 110 may acquire, as the amount of change V, the distance that a feature point included in the previous frame FR1 and the current frame FR2 has moved between the previous frame FR1 and the current frame FR2. Examples of feature points include the position detection pattern MK0 and the corners of the individual pattern TP1. When there are multiple feature points, the control unit 110 may acquire, as the amount of change V, the average value of multiple movement distances calculated for each of the multiple feature points. FIG. 7 shows how movement distances V1, V2, V3, and V4 of four position detection patterns MK0 are calculated based on the previous frame FR1 and the current frame FR2, and the amount of change V is acquired by averaging the movement distances Vi.

[0045] If the information terminal 1 is equipped with a sensor SS1, for example, a speed sensor or an acceleration sensor, the control unit 110 may acquire a detection value of the sensor SS1, for example, a speed value or an acceleration value, as the amount of change V. In this case, it is assumed that the medium ME0 is stationary.

[0046] The control unit 110 can determine whether the second condition is satisfied based on the acquired change amount V. If the change amount V is equal to or less than the threshold value THV, the control unit 110 determines that the second condition is satisfied. If the change amount V is greater than the threshold value THV, the control unit 110 determines that the second condition is not satisfied. If the second condition is not met, the control unit 110 outputs guidance for meeting the second condition in S108 shown in Fig. 5. Examples of outputting this guidance include displaying information such as "Please keep the camera steady" or outputting audio.

[0047] FIG. 8 schematically shows an example of whether a third condition that the imaging unit 120 is within a predetermined direct-facing range with respect to the imaging target area AR0 is satisfied. In FIG. 8, the shape of the imaging target area AR0 included in the frame FR0 is shown. The control unit 110 can determine whether the third condition is satisfied based on the shape of the imaging target area AR0 included in the frame FR0.

[0048] As described above, the control unit 110 determines whether the imaging target area AR0 is included in the frame FR0. When the imaging target area AR0 is rectangular and the imaging target area AR0 is included in the frame FR0, the control unit 110 can obtain the distance between adjacent corners C0 based on the frame FR0. In FIG. 8, the length LS1 corresponding to the vertical side S1 (see FIG. 3), the length LS2 corresponding to the vertical side S2 (see FIG. 3), the length LS3 corresponding to the horizontal side S3 (see FIG. 3), and the length LS4 corresponding to the horizontal side S4 (see FIG. 3) are shown. That the imaging unit 120 is within a predetermined direct-facing range with respect to the imaging target area AR0 means that the difference between the length LS1 of the vertical side S1 and the length LS2 of the vertical side S2 is small, and the difference between the length LS3 of the horizontal side S3 and the length LS4 of the horizontal side S4 is small. To quantitatively define the direct-facing range, threshold values TH1 and TH2 are applied to the vertical side length ratio LS1 / LS2 and the horizontal side length ratio LS3 / LS4. The threshold value TH1 is a positive value smaller than 1, and in the example shown in FIG. 8, 0.5 < TH1 < 1. The closer the threshold value TH1 is to 1, the more directly the imaging unit 120 faces the imaging target area AR0. The threshold value TH2 is a value greater than 1, and in the example shown in FIG. 8, 1 < TH1 < 2. The closer the threshold value TH2 is to 1, the more directly the imaging unit 120 faces the imaging target area AR0. When within the direct-facing range, that is, TH1 ≦ LS1 / LS2 ≦ TH2 and TH1 ≦ LS3 / LS4 ≦ TH2, the control unit 110 determines that the third condition is satisfied. When LS1 / LS2 < TH1, LS1 / LS2 > TH2, LS3 / LS4 < TH1, or LS3 / LS4 > TH2, the control unit 110 determines that the third condition is not satisfied. Of course, it is also possible to use the percentages 100×LS1 / LS2(%) and 100×LS3 / LS4(%) instead of the length ratios LS1 / LS2 and LS3 / LS4.

[0049] Further, the control unit 110 may obtain the angles θ1, θ2, θ3, and θ4 of the four corners C0 of the imaging target region AR0 based on the frame FR0. That the imaging unit 120 is within a predetermined facing range with respect to the imaging target region AR0 means that all of the angles θ1, θ2, θ3, and θ4 are near 90°. In order to quantitatively define the facing range, threshold values TH3 and TH4 are applied to the angles θ1, θ2, θ3, and θ4. The threshold value TH3 is a positive value smaller than 90°, and in the example shown in FIG. 8, 45° < TH3 < 90°. The closer the threshold value TH3 is to 90°, the more directly the imaging unit 120 faces the imaging target region AR0. The threshold value TH4 is a value larger than 90°, and in the example shown in FIG. 8, 90° < TH1 < 135°. The closer the threshold value TH4 is to 90°, the more directly the imaging unit 120 faces the imaging target region AR0. When within the facing range, that is, when TH3 ≤ θ1 ≤ TH4 and TH3 ≤ θ2 ≤ TH4 and TH3 ≤ θ3 ≤ TH4 and TH3 ≤ θ4 ≤ TH4, the control unit 110 determines that the third condition is satisfied. When θ1 < TH3, θ1 > TH4, θ2 < TH3, θ2 > TH4, θ3 < TH3, θ3 > TH4, θ4 < TH3, or θ4 > TH4, the control unit 110 determines that the third condition is not satisfied. Note that the control unit 110 may determine that the third condition is satisfied when both the condition for the length ratios LS1 / LS2 and LS3 / LS4 and the condition for the angles θ1 to θ4 are satisfied.

[0050] As described above, the control unit 110 determines whether the third condition is satisfied based on the shape of the imaging target region AR0 included in the frame FR0. When the third condition is not satisfied, the control unit 110 outputs guidance for satisfying the third condition in S108 shown in FIG. 5. Examples of the output of this guidance include display of information such as "Please face the camera toward the test pattern." or voice output.

[0051] FIG. 9 schematically shows an example of whether a fourth condition that a distortion amount DS indicating the distortion of the test pattern TP0 included in the frame FR0 is equal to or less than a threshold value THDS is satisfied. As shown in the middle part of FIG. 9, the shape of the test pattern TP0 included in the frame FR0 may be a shape in which distortion has occurred from the shape of the test pattern TP0 on the medium ME0 as shown in the upper part of FIG. 9. The control unit 110 can determine whether the fourth condition is satisfied based on the shape of the test pattern TP0 included in the frame FR0. The threshold value THDS is an example of a reference distortion amount and is a positive value.

[0052] When the region of the test pattern TP0 is rectangular and the test pattern TP0 is included in the frame FR0, the control unit 110 can obtain the distance between adjacent corners C1 in the rectangular region of the test pattern TP0 included in the frame FR0 based on the frame FR0. In FIG. 9, lengths LT1 and LT2 corresponding to the vertical sides and lengths LT3 and LT4 corresponding to the horizontal sides are shown. The distortion amount DS for the vertical side can be represented by a value greater than 1, for example, LT1 / LT2 when LT1>LT2 and LT2 / LT1 when LT1<LT2. The distortion amount DS for the horizontal side can be represented by a value greater than 1, for example, LT3 / LT4 when LT3>LT4 and LT4 / LT3 when LT3<LT4. When the threshold value THDS is set to a value greater than 1 and the distortion amount DS for the vertical side is equal to or less than the threshold value THDS and the distortion amount DS for the horizontal side is equal to or less than the threshold value THDS, the control unit 110 determines that the fourth condition is satisfied. The threshold value THDS is not particularly limited and can be set to 1.2 or the like. When the distortion amount DS for the vertical side is greater than the threshold value THDS or the distortion amount DS for the horizontal side is greater than the threshold value THDS, the control unit 110 determines that the fourth condition is not satisfied. Of course, it is also possible to use a percentage instead of the area ratio.

[0053] The control unit 110 may also determine angles α1, α2, α3, and α4 of the four corners C1 of the rectangular region of the test pattern TP0 based on the frame FR0. The distortion amount DS for the four corners C1 can be expressed, for example, as the difference |α1-90°|, |α2-90°|, |α3-90°|, and |α4-90°| between the angles α1, α2, α3, and α4 and the angle 90°. For example, assuming that the threshold value THDS is greater than 0° and less than 45°, if the differences |α1-90°|, |α2-90°|, |α3-90°|, and |α4-90°| are all equal to or less than the threshold value THDS, the control unit 110 can determine that the fourth condition is satisfied. When at least one of the differences |α1-90°|, |α2-90°|, |α3-90°|, and |α4-90°| is greater than the threshold value THDS, the control unit 110 can determine that the fourth condition is not satisfied. The control unit 110 may determine that the fourth condition is satisfied when both the conditions regarding the lengths LT1 to LT4 and the conditions regarding the angles α1 to α4 are satisfied.

[0054] Furthermore, if the frame FR0 includes a rectangular medium ME0, the control unit 110 may determine the angles θ1, θ2, θ3, and θ4 of the four corners C0 of the medium ME0 based on the frame FR0, as shown in FIG. 8. The distortion amount DS for the four corners C0 can be expressed, for example, as the difference |θ1-90°|, |θ2-90°|, |θ3-90°|, and |θ4-90°| between the angles θ1, θ2, θ3, and θ4 and the angle 90°. If any of these differences is equal to or less than the threshold THDS, the control unit 110 can determine that the fourth condition is satisfied. If at least one of the differences |θ1-90°|, |θ2-90°|, |θ3-90°|, and |θ4-90°| is greater than the threshold THDS, the control unit 110 can determine that the fourth condition is not satisfied.

[0055] In this way, the control unit 110 determines whether the fourth condition is met based on the shape of the test pattern TP0 included in the frame FR0. If the fourth condition is not met, the control unit 110 outputs guidance for meeting the fourth condition in S108 shown in Fig. 5. Examples of output guidance include displaying or outputting audio information such as "Please point the camera so that the test pattern is not distorted."

[0056] 10 is a diagram illustrating an example of whether the fifth condition, that is, the distance D between the image capture unit 120 and the medium ME0 is equal to or less than the threshold THD, is satisfied. The threshold THD is an example of a reference distance and is a positive value. As described above, the control unit 110 determines whether the imaging target area AR0 is included in the frame FR0. If the imaging target area AR0 is included in the frame FR0, the control unit 110 can calculate the area Sa of the imaging target area AR0 based on the frame FR0. Here, the area of ​​the frame FR0 is assumed to be Sf. The area ratio Sa / Sf of the imaging target area AR0 to the frame FR0 increases as the imaging unit 120 gets closer to the medium ME0, and decreases as the imaging unit 120 gets farther away from the medium ME0. Since the maximum value of the area ratio Sa / Sf is 1, the distance D can be expressed as 1-(Sa / Sf).

[0057] If the information terminal 1 is equipped with a sensor SS2, for example, a distance measurement sensor, the control unit 110 may acquire, as the distance amount D, a detection value of the sensor SS2, for example, the distance from the imaging unit 120 to the medium ME0.

[0058] The control unit 110 can determine whether the fifth condition is met based on the acquired interval amount D. If the interval amount D is equal to or less than the threshold value THD, the control unit 110 determines that the fifth condition is met. If the interval amount D is greater than the threshold value THD, the control unit 110 determines that the fifth condition is not met. Note that if the interval amount D is extremely close to 0, the first condition is not met, so it is sufficient to have a threshold value THD that indicates the upper limit of the interval amount D. The control unit 110 may determine that the fifth condition is satisfied when both the condition based on the area ratio Sa / Sf and the condition based on the detection value of the sensor SS2 are satisfied.

[0059] If the fifth condition is not met, the control unit 110 outputs guidance for meeting the fifth condition in S108 shown in Fig. 5. Examples of outputting this guidance include displaying information such as "Please move the camera closer to the test pattern" or outputting a voice message.

[0060] 11A and 11B schematically illustrate an example of whether the sixth condition, that is, the brightness amount L0 indicating the brightness L of the background color of the medium ME0 is equal to or greater than the threshold value THL, is satisfied. The brightness L may be a luminance value calculated from the pixel values ​​of the frame FR0, such as the average value of the R (red), G (green), and B (blue) values, or a brightness value calculated from the pixel values ​​of the frame FR0. The threshold value THL is an example of a reference brightness amount and is a positive value.

[0061] Generally, the background color of the medium ME0 is brighter than the test pattern TP0. When the number of pixels Np is plotted against brightness L in a frame FR0 obtained from the imaging unit 120 facing the medium ME0, a peak P1 of brightness LP1 corresponding to the background color of the medium ME0 and a peak P2 of brightness corresponding to the test pattern TP0 appear. Peak P1 is brighter than peak P2. As shown in FIG. 11A, if the brightness LP1 of peak P1 is defined as a brightness amount L0, a threshold value for this brightness amount L0 can be set as THL. This threshold value THL is a positive value smaller than the upper limit of brightness L. If the brightness amount L0 is equal to or greater than the threshold THL, the control unit 110 can determine that the sixth condition is satisfied. If the brightness amount L0 is smaller than the threshold THL, the control unit 110 can determine that the sixth condition is not satisfied. Instead of the brightness LP1 of the peak P1, a statistically representative value such as the average value of the number of pixels Np at the brightness L where the number of pixels Np exceeds a predetermined value can also be used.

[0062] As shown in FIG. 11B, the control unit 110 may calculate the area St of the graph equal to or greater than a positive threshold THS that is smaller than the upper limit of brightness L, for example, the sum of the number of pixels Np equal to or greater than the threshold THS. The area St increases as the background color of the medium ME0 increases, and decreases as the background color of the medium ME0 decreases. If the area St is defined as the brightness amount L0, then the threshold for this brightness amount L0 can be set to THL. This threshold THL is a positive value smaller than the area Sh of the entire graph, for example, the number of pixels in frame FR0. Furthermore, the area ratio St / Sh of the entire graph equal to or greater than the threshold THS increases as the background color of the medium ME0 increases, and decreases as the background color of the medium ME0 decreases. If the area ratio St / Sh is defined as the brightness amount L0, then the threshold for this brightness amount L0 can be set to THL. This threshold THL is a positive value smaller than 1. Of course, the area ratio St / Sh can also be replaced by the percentage 100×St / Sh (%). If the brightness amount L0 is equal to or greater than the threshold value THL, the control unit 110 can determine that the sixth condition is met. If the brightness amount L0 is less than the threshold value THL, the control unit 110 can determine that the sixth condition is not met.

[0063] Furthermore, the determination of whether the sixth condition is met may be performed by a known method other than the above-described method. In this way, the control unit 110 acquires the brightness amount L0 of the background color of the medium ME0 based on the frame FR0, and determines whether the sixth condition is met based on the acquired brightness amount L0. If the sixth condition is not met, the control unit 110 outputs guidance for meeting the sixth condition in S108 shown in FIG. 5. Examples of output guidance include displaying or outputting audio information such as "Please make the test pattern a bright environment."

[0064] 12 schematically shows an example of criteria for determining the imaging conditions. The control unit 110 determines whether two or more of the six conditions are satisfied, and when the two or more conditions are satisfied, the control unit 110 triggers the imaging unit 120 to capture an image of the imaging target area AR0, thereby acquiring the captured image IM0. The imaging conditions may be an AND condition of the six conditions, but as long as the first and second conditions are included, the third condition, the fourth condition, the fifth condition, and the sixth condition may not be required. In this specific example, since imaging is triggered when at least the first and second conditions are satisfied, an image IM0 with an appropriate imaging range and minimal blur is obtained. This allows an appropriate captured test pattern image to be used to adjust printing characteristics, and prevents unnecessary captured images from overwhelming memory.

[0065] The control unit 110 can acquire adjustment values ​​for adjusting the printing characteristics of the printing device 2 based on the pixel values ​​of the test pattern TP0 included in the captured image IM0. If the test pattern TP0 is a density pattern for adjusting the density of the print image PI0, the control unit 110 can acquire density adjustment values ​​for adjusting the density of the print image PI0 based on the pixel values ​​of the test pattern TP0. If the test pattern TP0 is a Bi-d adjustment pattern for Bi-d adjustment, the control unit 110 can acquire Bi-d adjustment values ​​for performing the Bi-d adjustment based on the pixel values ​​of the test pattern TP0. If the test pattern TP0 is a transport distance adjustment pattern for adjusting the transport distance of the medium ME0, the control unit 110 can acquire transport distance adjustment values ​​for adjusting the transport distance of the medium ME0 based on the pixel values ​​of the test pattern TP0.

[0066] FIG. 13 shows a schematic example of the adjustment of printing characteristics. Density adjustment refers to setting an adjustment value A1 to match the density of the print image PI0 to that of the input image. For example, as shown in FIG. 13, assume that the print image PI0 is darker than the input image. In this case, the output density of the individual pattern TP1 is darker than the density of the individual pattern data DA1 used to form the individual pattern TP1. The control unit 110 can cause the printing device 2 to perform density adjustment by, for example, setting an adjustment value A1 corresponding to the deviation in the output density of the individual pattern TP1 from the density of the individual pattern data DA1 in the controller 210 of the printing device 2. The controller 210 can match the density of the print image PI0 to that of the input image by lightening the output density of the individual pattern TP1 corresponding to the individual pattern data DA1 to that of the individual pattern data DA1 in accordance with the adjustment value A1. Of course, even if the print image PI0 is lighter than the input image, the density of the print image PI0 can be matched to that of the input image by setting the adjustment value A1.

[0067] Bi-d adjustment refers to setting an adjustment value A2 to align the landing positions of droplets 280 on the forward pass with the landing positions of droplets 280 on the backward pass in the main scanning direction D1 when the printing device 2 repeats main and sub scans during printing. Here, the forward pass refers to a main scan in which the recording head 220 moves in the forward direction D11, and the backward pass refers to a main scan in which the recording head 220 moves in the backward direction D12. For example, as shown in FIG. 13 , the landing positions on the backward pass that should be aligned with the landing positions on the forward pass in the main scanning direction D1 are shifted in the forward direction D11 from the landing positions on the forward pass. In this case, the position of the individual pattern TP1 formed on the medium ME0 on the backward pass is shifted in the forward direction D11 from the position of the individual pattern TP1 formed on the medium ME0 on the forward pass. The control unit 110 can cause the printing device 2 to perform Bi-d adjustment, for example, by setting an adjustment value A2 corresponding to the positional deviation of the individual pattern TP1 in the controller 210 of the printing device 2. The controller 210 can align the landing positions of the droplets 280 in the main scanning direction D1 between the forward and backward passes by delaying the ejection timing of the droplets 280 from the recording head 220 on the backward pass in accordance with the adjustment value A2. Of course, even if the landing position on the backward pass that should be aligned with the landing position on the forward pass in the main scanning direction D1 is shifted in the backward direction D12 from the landing position on the forward pass, the setting of the adjustment value A2 can align the landing positions of the droplets 280 in the main scanning direction D1 between the forward and backward passes.

[0068] PF adjustment, which is used to adjust the transport distance, involves setting an adjustment value A3 to accurately adjust the transport distance of medium ME0 during sub-scanning in the sub-scanning direction D2. Note that sub-scanning direction D2 refers to the direction in which the recording head 220 moves relative to medium ME0, and the transport direction in which medium ME0 moves relative to the recording head 220 is opposite to sub-scanning direction D2. If the transport distance of medium ME0 during sub-scanning is too large, gaps between band regions will appear, e.g., light streaks. If the transport distance of medium ME0 during sub-scanning is too small, overlapping dots will appear between band regions, e.g., dark streaks. For example, as shown in FIG. 13, the spacing between the landing positions of droplets 280 between sub-scans in the sub-scanning direction D2 is assumed to be wider than the design width WB of the band region. In this case, the spacing between individual patterns TP1 formed on medium ME0 during a certain pass and individual patterns TP1 formed on medium ME0 during the previous pass will be wider than the width WB of the band region. The control unit 110 can cause the printing device 2 to perform PF adjustment by, for example, setting an adjustment value A3 in the controller 210 of the printing device 2, which corresponds to the deviation in the spacing between the individual patterns TP1 relative to the width WB of the band area. The controller 210 can adjust the transport amount of the medium ME0 during sub-scans in the sub-scanning direction D2 so that it is neither too much nor too little, by reducing the transport amount of the medium ME0 during sub-scans in accordance with the adjustment value A3. Of course, even if the distance between the landing positions of the droplets 280 between sub-scans in the sub-scanning direction D2 is narrower than the designed width WB of the band area, the setting of the adjustment value A3 can also adjust the transport amount of the medium ME0 during sub-scans so that it is neither too much nor too little.

[0069] As described above, the user US1 can easily adjust various printing characteristics by capturing an image of the test pattern TP0 with a portable information terminal 1 such as a mobile terminal with a camera.

[0070] (4) Variation: The present invention can be embodied in various modifications. For example, the above-described processes can be changed as appropriate, such as by changing the order of the processes. For example, in the imaging control process of Fig. 5, the condition satisfaction determination information acquisition process of S104 can be performed before the process of S102. Furthermore, even if the guidance output process of S108 is not performed, the effect of being able to capture an appropriate test pattern can be obtained.

[0071] As shown in Fig. 14, imaging may be performed repeatedly while imaging conditions are satisfied. Fig. 14 schematically shows an example of continuous shooting control processing performed by the control unit 110. The continuous shooting control processing starts when the control unit 110 receives a continuous shooting instruction for the imaging target area AR0 via the operation unit 115. The continuous shooting instruction may be an operation on a continuous shooting instruction area displayed after the imaging control program PR0 is started, an operation on the shutter button, or an operation to start the imaging control program PR0, etc.

[0072] When the continuous shooting control process starts, the control unit 110 receives input of the number of times Nt to repeat imaging of the imaging target area AR0 via the operation unit 115 (S202). The number of times Nt is an integer equal to or greater than 1, and if continuous shooting is required, an integer equal to or greater than 2. Thereafter, the control unit 110 performs the processes of S102 to S110 shown in Fig. 5, and acquires the captured image IM0 by causing the imaging unit 120 to capture the imaging target area AR0 when the imaging conditions are satisfied as a trigger. After acquiring the captured image IM0, the control unit 110 determines whether or not imaging of the imaging target area AR0 has been performed Nt times (S204). If imaging of the imaging target area AR0 has been performed less than Nt times, the control unit 110 again performs the processes of S102 to S110 shown in Fig. 5. In this way, the control unit 110 causes the imaging unit 120 to repeatedly perform imaging of the imaging target area AR0 Nt times when the imaging conditions are satisfied.

[0073] When imaging of the imaging target area AR0 has been performed Nt times, the control unit 110 determines whether or not to save the Nt captured images IM0 as file FL0 (S206). For example, when the operation unit 115 accepts an operation to save the captured images IM0, the control unit 110 converts each captured image IM0 into the format of file FL0 and saves it in the storage unit 114 (S208), and ends the continuous shooting control process. When the operation unit 115 accepts an operation to discard the captured images IM0, the control unit 110 ends the continuous shooting control process without performing the save process of S208. As a result, appropriate test pattern images can be obtained multiple times, allowing for more appropriate adjustment of printing characteristics.

[0074] (5) Conclusion: As described above, the present invention can provide a configuration capable of capturing an appropriate test pattern through various aspects. Of course, even in an aspect consisting only of the features of the independent claims, the basic functions and effects described above can be obtained. Furthermore, it is possible to implement configurations in which the components disclosed in the above examples are substituted with each other or the combination is changed, or configurations in which the components disclosed in the publicly known techniques and the above examples are substituted with each other or the combination is changed, etc. The present invention also includes these configurations. [Explanation of symbols]

[0075] 1...information terminal, 2...printing device, 110...controller, 111...CPU, 113...RAM, 114...storage unit, 115...operation unit, 116...display unit, 120...imaging unit, 123...image sensor, 210...controller, 220...recording head, AR0...imaging target area, C0...corner, D...spacing amount, DS...distortion amount, FA...angle of view, FR0...frame, FU1...judgment function, FU2...imaging control function, FU3...guidance function, IM0...captured image, L ...brightness, L0...amount of brightness, LS1 to LS4, LT1 to LT4...length, ME0...medium, MK0...position detection pattern, Nt...number of times, Np...number of pixels, P1, P2...peak, PI0...printed image, PR0...imaging control program, S1, S2...vertical side, S3, S4...horizontal side, Sa, Sf, Sh, St...area, SS1, SS2...sensor, SY1...printing system, TP0...test pattern, TP1...individual pattern, V...amount of change, VD0...video.

Claims

1. 1. An imaging control program for imaging a medium having a test pattern for adjusting printing characteristics of a printing device having a recording head, comprising: a determination function for determining whether or not an imaging condition for causing an imaging unit to capture an image of an imaging target area including the test pattern is satisfied; an imaging control function of acquiring a captured image by causing the imaging unit to capture an image of the imaging target area when the imaging condition is satisfied; the determining function repeatedly acquires a change in the relative positional relationship between the imaging unit and the medium; the imaging condition is a condition in which at least a first condition that the imaging target area is included in an angle of view of the imaging unit and a second condition that the acquired change amount is equal to or less than a reference change amount are satisfied; The judgment function is an imaging control program that judges whether the first condition is met based on frames repeatedly acquired from the imaging unit, and judges whether the second condition is met based on the acquired amount of change.

2. the imaging condition is a condition in which at least the first condition, the second condition, and a third condition in which the imaging unit is within a predetermined range directly facing the imaging target area are satisfied; The imaging control program according to claim 1 , wherein the determining function determines whether the third condition is satisfied based on a shape of the imaging target area included in the frame.

3. the imaging condition is a condition in which at least the first condition, the second condition, and a fourth condition in which a distortion amount indicating a distortion of the test pattern included in the frame is equal to or less than a reference distortion amount are satisfied; The imaging control program according to claim 1 , wherein the determining function determines whether the fourth condition is satisfied based on a shape of the test pattern included in the frame.

4. the determination function repeatedly detects a gap amount corresponding to a gap between the imaging unit and the medium; the imaging condition is a condition in which at least the first condition, the second condition, and a fifth condition that the gap amount is equal to or less than a reference gap amount are satisfied; The imaging control program according to claim 1 , wherein the determining function determines whether the fifth condition is satisfied based on the detected amount of space.

5. the determining function obtains a brightness amount indicating the brightness of the background color of the medium based on the frame; the imaging conditions are conditions in which at least the first condition, the second condition, and a sixth condition that the brightness amount is equal to or greater than a reference brightness amount are satisfied, The imaging control program according to claim 1 , wherein the determining function determines whether the sixth condition is satisfied based on the acquired brightness amount.

6. The imaging conditions are: The first condition, The second condition, a third condition that the imaging unit is within a predetermined range of direct facing with respect to the imaging target area; a fourth condition that a distortion amount indicating distortion of the test pattern included in the frame is equal to or less than a reference distortion amount; A fifth condition is that the spacing amount is equal to or less than a reference spacing amount, and a sixth condition that the brightness amount is equal to or greater than a reference brightness amount is satisfied; The determination function is determining whether the third condition is satisfied based on the shape of the imaging target area included in the frame; determining whether the fourth condition is satisfied based on the shape of the test pattern included in the frame; repeatedly detecting a gap amount corresponding to a gap between the imaging unit and the medium, and determining whether the fifth condition is satisfied based on the detected gap amount; The imaging control program according to claim 1 , further comprising: obtaining a brightness amount indicating brightness of a background color of the medium based on the frame; and determining whether the sixth condition is satisfied based on the obtained brightness amount.

7. The imaging control program according to claim 1, wherein the imaging control function accepts input of the number of times to repeat imaging of the imaging target area, and causes the imaging unit to repeatedly image the imaging target area the number of times when the imaging condition is satisfied.

8. The imaging control program according to any one of claims 1 to 7, further comprising causing the computer to realize a guidance function that outputs guidance for satisfying a condition when any of the multiple conditions included in the imaging conditions is not satisfied.

9. A printing system including a printing device including a recording head and an information terminal that captures an image of a medium having a test pattern for adjusting the printing characteristics of the printing device, The information terminal An imaging unit; a control unit including a memory for storing an image obtained from the imaging unit, and causing the imaging unit to capture an image of an imaging target area including the test pattern; the control unit repeatedly acquires a change in the relative positional relationship between the imaging unit and the medium, determines whether or not an imaging condition for causing the imaging unit to capture an image of the imaging target area is satisfied, and acquires the captured image by causing the imaging unit to capture an image of the imaging target area when the imaging condition is satisfied; the imaging condition is a condition in which at least a first condition that the imaging target area is included in an angle of view of the imaging unit and a second condition that the acquired change amount is equal to or less than a reference change amount are satisfied; The control unit determines whether the first condition is satisfied based on frames repeatedly acquired from the imaging unit, and determines whether the second condition is satisfied based on the acquired amount of change.

Images