Printing device and printing method

Abstract

To provide a printing method capable of preventing generation of extraction leakage of a pattern.SOLUTION: A printer has a pattern extraction section for extracting a pattern area from second image data on the basis of a contrast between first image data representing a pattern and the second image data generated by imaging a conveyed cloth, a printing image generation section for generating third image data representing an image to be printed on the pattern by arranging so as to match a pattern area, and a print control section for executing printing of the print image data on a conveyed cloth on a printer, in which the pattern extraction portion executes a first extraction treatment of the pattern area with the first area of the second image data as a target, and second extraction treatment of a pattern area with a second region of the second image data as a target, a portion of the second region is an OL area overlapping with the first area, and a length in a conveying direction of the OL area is longer than a length in the conveying direction of the first image data.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a printing device and a printing method. [Background technology]

[0002] There is known a technique for searching for candidates in an inspection target image that are similar in features to a reference image obtained by photographing a non-defective product that serves as a reference for the product (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-96750 A Summary of the Invention [Problem to be solved by the invention]

[0004] Here, when a fabric with a pattern formed thereon is used as a printing medium, it is assumed that the pattern is extracted from a captured image obtained by capturing an image of the fabric as it is transported. Since the captured image is obtained sequentially in sections as the fabric is transported, the pattern is extracted in units of regions obtained by dividing the captured image into sections of a certain area. However, there is a problem in that a pattern located across a boundary between such regions cannot be extracted even in a pattern extraction process that targets either of the adjacent regions at the boundary. [Means for solving the problem]

[0005] The printing device includes a conveying unit that conveys fabric on which a pattern is formed in a conveying direction, an imaging unit that images the fabric conveyed by the conveying unit, a printing unit that prints on the fabric conveyed by the conveying unit, a pattern extraction unit that extracts a pattern area corresponding to the pattern in the second image data based on a comparison between first image data that represents the pattern and second image data generated by the imaging unit imaging the fabric, a print image generation unit that generates print image data by arranging third image data that represents an image to be printed over the pattern to match the extracted pattern area, and a print control unit that causes the printing unit to print the print image data on the fabric, wherein the pattern extraction unit executes a first extraction process that extracts the pattern area from a first area of ​​the second image data and a second extraction process that extracts the pattern area from a second area of ​​the second image data, wherein a portion of the second area is an overlap area that overlaps with the first area, and the length of the overlap area in the conveying direction is equal to or greater than the length of the first image data in the conveying direction.

[0006] The printing method includes a conveying step of conveying fabric on which a pattern has been formed in a conveying direction; an imaging step of imaging the fabric as it is conveyed; a pattern extraction step of extracting a pattern area in the second image data corresponding to the pattern based on a comparison between first image data representing the pattern and second image data generated by imaging the fabric; a print image generation step of generating print image data by arranging third image data representing an image to be printed over the pattern to match the extracted pattern area; and a printing step of printing the print image data on the fabric as it is conveyed, wherein the pattern extraction step executes a first extraction process of extracting the pattern area from a first area of ​​the second image data and a second extraction process of extracting the pattern area from a second area of ​​the second image data, wherein a portion of the second area is an overlap area that overlaps with the first area, and the length of the overlap area in the conveying direction is equal to or greater than the length of the first image data in the conveying direction. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a block diagram showing a simplified configuration of a printing apparatus. [Figure 2] 2A is a view showing the transported fabric and the surrounding structure from a top-down perspective, and FIG. 2B is a view showing a part of the structure shown in FIG. 2A from an upstream-downstream perspective. [Figure 3] 10 is a flowchart showing a printing process. [Figure 4] 10 is a flowchart showing the details of step S100. [Figure 5] 10 is a flowchart showing the details of step S120. [Figure 6] FIG. 10 is a diagram for explaining steps S121 to S126 using a specific example. [Figure 7] FIG. 10 is a diagram for explaining steps S130 and S140 using a specific example. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the drawings are merely examples for explaining the present embodiment. Because the drawings are examples, the proportions and shapes may not be accurate, the drawings may not match each other, and some parts may be omitted.

[0009] 1.Device configuration: FIG. 1 shows a simplified configuration of a printing device 10 according to this embodiment. The printing device 10 executes a printing method. The printing device 10 includes a control unit 11, a display unit 13, an operation reception unit 14, an imaging unit 15, a conveying unit 16, a printing unit 17, and a storage unit 18. The control unit 11 includes one or more ICs having a CPU 11a as a processor, a ROM 11b, a RAM 11c, and the like, as well as other non-volatile memories.

[0010] In the control unit 11, a processor, i.e., CPU 11a, executes arithmetic processing in accordance with one or more programs 12 stored in ROM 11b or other memory, using RAM 11c or the like as a work area, thereby controlling the printing device 10. By following the programs 12, the control unit 11 functions as a pattern registration unit 12a, pattern extraction unit 12b, print image generation unit 12c, print control unit 12d, etc. Note that the processor is not limited to a single CPU, and may be configured to perform processing using multiple CPUs or hardware circuits such as ASICs, or may be configured to perform processing in cooperation with a CPU and hardware circuits.

[0011] The display unit 13 is a means for displaying visual information and is configured, for example, by a liquid crystal display, an organic EL display, or the like. The display unit 13 may be configured to include a display and a drive circuit for driving the display. The operation reception unit 14 is a means for receiving operations by a user and is realized, for example, by physical buttons, a touch panel, a mouse, a keyboard, or the like. Of course, the touch panel may be realized as one function of the display unit 13. The display unit 13 and the operation reception unit 14 may be part of the configuration of the printing device 10, or may be peripheral devices external to the printing device 10.

[0012] The transport unit 16 is a mechanism that transports the print medium under the control of the control unit 11. In this embodiment, the print medium is assumed to be a fabric, such as a jacquard woven fabric or lace fabric, on which a three-dimensional pattern is formed by specially weaving threads or fibers. The fabric has one or a group of patterns formed in a repeated pattern. In the following, one or a group of patterns will be treated as one pattern.

[0013] Conveying unit 16 includes, for example, a feed roller that feeds the unprinted fabric wound in a roll downstream in the conveyance direction, a belt and rollers for further conveying the fed fabric, a take-up roller that rewinds the fabric into a roll and collects it after printing, a motor for rotating each roller and belt, etc. Hereinafter, the upstream and downstream in the conveying direction by conveying unit 16 will also be simply referred to as upstream and downstream.

[0014] The imaging unit 15, under the control of the control unit 11, captures an image of the fabric being conveyed by the conveying unit 16. The imaging unit 15 includes a light source that illuminates the fabric, an imaging element that receives light reflected from the fabric, and generates and outputs image data as the imaging result.

[0015] The printing unit 17 prints on the fabric conveyed by the conveying unit 16 under the control of the control unit 11. The printing unit 17 is located downstream of the imaging unit 15. The printing unit 17 prints on the fabric based on print image data sent from the control unit 11. The printing unit 17 can print by ejecting ink of multiple colors such as cyan, magenta, yellow, and black using an inkjet method, for example. Using the inkjet method, the printing unit 17 prints on the fabric by ejecting ink dots from nozzles (not shown) based on print image data that specifies dot-on or dot-off for each ink for each pixel.

[0016] The storage unit 18 is a storage means such as a nonvolatile memory, a hard disk drive, etc. The storage unit 18 may be considered as part of the control unit 11. The RAM 11c may also be considered as part of the storage unit 18.

[0017] The printing device 10 may also be called a recording device, an image forming device, a printer, etc. The printing device 10 may be realized not only by a single independent device, but also by multiple devices connected to each other so that they can communicate with each other via a communication interface or a network. A printing device 10 made up of multiple devices may also be called a printing system 10.

[0018] The printing system 10 is configured to include, for example, a printer including an imaging unit 15, a transport unit 16, and a printing unit 17, and one or more information processing devices that function as the control unit 11. The information processing device is, for example, a personal computer (PC), a server, a smartphone, a tablet terminal, or a device with processing capabilities equivalent to those. In the printing system 10, the device that functions as the control unit 11 may also be called an image processing device, a print control device, or the like. Of course, some of the devices that make up the printing system 10 can also be considered as inventions.

[0019] Figure 2A shows the transported fabric 30 and the structure around the fabric 30 from a perspective looking downward. In Figure 2A, the pattern that has been pre-formed on the fabric 30 is not shown. In Figure 2A, the direction in which the fabric 30 is transported by the transport unit 16 is indicated by reference symbol D1. Reference symbol 22 denotes an endless belt 22 that is part of the transport unit 16. The fabric 30 placed on the endless belt 22 is transported from upstream to downstream as the endless belt 22 rotates.

[0020] As shown in FIG. 2A, a carriage 20 is disposed above the endless belt 22. The carriage 20 is capable of reciprocating movement along a direction D2 that intersects with the conveyance direction D1. Here, "intersecting" means "perpendicular," but "perpendicular" can be understood to include not only strict perpendicularity but also tolerances that arise during product manufacturing. The carriage 20 moves along a long guide member 21 in the direction D2. The direction D2 is also referred to as the main scanning direction of the carriage 20 and the print head 19. The direction D2 is also referred to as the width direction of the fabric 30.

[0021] The carriage 20 carries a print head 19. In other words, the print head 19 moves back and forth together with the carriage 20 in the width direction D2. The carriage 20 and print head 19 constitute the printing unit 17. Although not shown, the print head 19 has multiple nozzles open on its underside, which faces the endless belt 22. As the print head 19 moves together with the carriage 20 in the width direction D2, it ejects ink from the nozzles based on print image data.

[0022] As shown in FIG. 2A, the imaging unit 15 is disposed at a predetermined position above the endless belt 22 and upstream of the carriage 20 and the print head 19. FIG. 2B shows a portion of the configuration shown in FIG. 2A from a perspective looking from upstream to downstream. The imaging unit 15 has an imaging surface 15a on its lower surface facing the endless belt 22, and captures an image of the fabric 30 on the endless belt 22 through the imaging surface 15a. The imaging unit 15 is, for example, a line-scan camera with multiple imaging elements arranged along the width direction D2 inside. The imaging unit 15 repeatedly captures images line by line through a lens and imaging elements (not shown) provided on the imaging surface 15a. In FIG. 2B, the imaging range of the imaging unit 15 in the width direction D2 is illustrated by a dashed line. The imaging unit 15 is able to capture images of almost the entire range of the endless belt 22 in the width direction D2 due to the function of the lens.

[0023] 2A and 2B. For example, a configuration may be adopted in which multiple imaging units 15 are lined up above the endless belt 22 along the width direction D2, with each of the multiple imaging units 15 taking responsibility for capturing images of a portion of the entire range of the endless belt 22 in the width direction D2. Alternatively, the imaging unit 15 may be a line sensor configured by arranging multiple imaging elements over almost the entire range of the endless belt 22 in the width direction D2. Alternatively, the imaging unit 15 may be mounted on a carriage that is movable along the width direction D2, similar to the print head 19 being mounted on the carriage 20, and may capture images of the endless belt 22 while moving in the width direction D2 by the carriage.

[0024] 2.Printing method: FIG. 3 is a flowchart showing the printing process that the control unit 11 executes in accordance with the program 12. In step S100, the pattern registration unit 12a of the control unit 11 registers pattern image data representing the pattern formed on the fabric 30 in the storage unit 18. The pattern image data corresponds to "first image data," and step S100 corresponds to a registration process.

[0025] FIG. 4 is a flowchart showing the details of step S100. In step S102, the pattern registration unit 12a acquires basic image data representing the pattern of the fabric 30. The fabric 30 is, for example, a woven fabric into which a single pattern designed by a designer is repeatedly woven. Therefore, the basic image data is assumed to be image data representing the single pattern that has been generated in advance using predetermined software for design and drafting. In accordance with a user's operation, the pattern registration unit 12a inputs basic image data stored in a PC, for example, from an external PC to the printing device 10, and stores the input basic image data in the storage unit 18.

[0026] In step S104, the pattern registration unit 12a acquires prescanned data, which is image data generated by prescanning the fabric 30. Prescanning refers to reading or capturing an image prior to capturing an image of the fabric 30, which begins in step S110, described below. For example, the user causes a scanner external to the printing device 10 to scan the fabric 30 in advance. The pattern registration unit 12a then inputs the image data generated by this scanning from the scanner and stores it in the storage unit 18 as prescanned data.

[0027] Alternatively, the pre-scanning may be performed by the imaging unit 15. For example, the control unit 11 causes the conveying unit 16 to start conveying the fabric 30, and stops conveying the fabric 30 when the leading edge of the fabric 30 reaches a position a predetermined distance downstream from the imaging unit 15. The leading edge of the fabric 30 is the end of the fabric 30 facing downstream. The imaging unit 15 captures an image of the fabric 30 passing under the imaging unit 15 during conveyance, and the pattern registration unit 12a inputs image data generated by this imaging from the imaging unit 15 and stores it in the storage unit 18 as pre-scan data.

[0028] In step S106, the pattern registration unit 12a compares the basic image data acquired in step S102 with the pre-scan data acquired in step S104, and extracts a pattern area in the pre-scan data that corresponds to one pattern of the fabric 30. At this time, the pattern registration unit 12a uses image recognition technology to extract an image area in the pre-scan data that has a higher similarity to the basic image data, and sets this image area as a pattern area.

[0029] Then, in step S108, the pattern registration unit 12a stores the image data corresponding to the pattern region extracted in step S106 as pattern image data in the storage unit 18. This completes the registration of the pattern image data. According to the explanation in accordance with FIG. 4, the pattern image data can be said to be at least a part of the pre-scan data. However, the pattern registration unit 12a may simplify step S100 by registering the basic image data itself in the storage unit 18 as pattern image data.

[0030] Returning to the explanation of Figure 3. In step S110, the control unit 11 causes the imaging unit 15 to start imaging the fabric 30 being transported by the transport unit 16 at a predetermined speed. That is, in step S110, the "transportation process" of the fabric 30 is started. Also, step S110 starts the "imaging process." Line-by-line image data generated by the imaging unit 15 by capturing images of the fabric 30 is output sequentially to the control unit 11. The control unit 11 acquires two-dimensional captured image data by sequentially saving the line-by-line image data from the imaging unit 15. The captured image data corresponds to "second image data."

[0031] In step S120, the pattern extraction unit 12b extracts a pattern area corresponding to the pattern of the fabric 30 in the captured image data based on a comparison between the pattern image data registered in step S100 and the captured image data generated by capturing an image in step S110. A plurality of patterns are represented in a line in the captured image data. Therefore, the pattern extraction unit 12b extracts a pattern area for each of the patterns represented in a line in the captured image data. Step S120 corresponds to a "pattern extraction step."

[0032] FIG. 5 is a flowchart showing the details of step S120. In step S121, the pattern extraction unit 12b sets a first region of a predetermined size within the captured image data. In this embodiment, the orientations of each piece of image data, such as the pattern image data, captured image data, and print image data handled by the control unit 11, will be described in relation to the conveying direction D1 and the width direction D2. Furthermore, with regard to the ends of the image data and the regions within the image data, the downstream end is referred to as the leading end, and the upstream end is referred to as the trailing end.

[0033] The pattern extraction unit 12b sets the length of the first region in the width direction D2 to be the same as the length of the captured image data in the width direction D2. The length here refers to, for example, the number of pixels. Furthermore, when the length of the pattern image data in the transport direction D1 is A, the pattern extraction unit 12b determines a length H that is equal to or greater than A, and sets the length of the first region in the transport direction D1 to H×2. For example, H=A, H=A×1.2, or H=A×1.5.

[0034] In step S122, the pattern extraction unit 12b performs a first extraction process to extract a pattern region from the first region. Using image recognition technology, the pattern extraction unit 12b extracts an image region whose similarity to the pattern image data is higher than a predetermined level as a pattern region. Specifically, the pattern extraction unit 12b extracts edges of the image in the pattern image data and similarly extracts edges of the image in the captured image data. The pattern extraction unit 12b then repeatedly compares the distribution of edges in the pattern image data with the distribution of edges in the captured image data while shifting their positions and while deforming the pattern image data, and extracts a region where the degree of similarity between the edge distributions is evaluated as being higher than a predetermined level as a single pattern region. Through this process, the pattern extraction unit 12b extracts a pattern region from within the currently targeted region of the captured image data.

[0035] Here, if the width direction D2 is considered to be the X-axis and the conveyance direction D1 is considered to be the Y-axis, the coordinates of the captured image data are defined on a two-dimensional plane by the orthogonal X and Y axes. The process of extracting a pattern area from the captured image data is also a process of identifying the coordinates of the pattern area within the captured image data. Note that, similar to the process of step S122, in the above-mentioned step S106, the pattern registration unit 12a can extract a pattern area within the pre-scan data depending on the degree of match in the edge distribution between the compared images.

[0036] In step S123, the pattern extraction unit 12b sets a second region in the captured image data upstream of the first region, overlapping with a portion of the first region in the conveying direction D1. In other words, the second region is set so that the leading edge of the second region is located downstream of the end of the first region. The size of the second region is the same as that of the first region. The region where the first region and the second region overlap is called the OL region. OL stands for overlap. The length of the OL region in the conveying direction D1 is called the OL distance, and the OL distance = H. Because the length of the first region and the second region in the conveying direction D1 is H × 2, half of the area of ​​the first region and the second region overlap each other.

[0037] In step S124, the pattern extraction unit 12b performs a second extraction process to extract a pattern region from the second region as a target. The method for extracting a pattern region from within the target region is the same as in the first extraction process.

[0038] In step S125, the pattern extraction unit 12b sets a boundary line in the first region or the second region, which line intersects with the conveying direction D1 and corresponds to the boundary between the pattern regions, in accordance with the extraction results of the pattern regions in steps S122 and S124. If the end of the first region corresponds to the boundary between the pattern regions, the pattern extraction unit 12b may set the end of the first region as the boundary line.

[0039] In step S126, the pattern extraction unit 12b outputs information about the pattern area in the area downstream from the boundary line set in step S125 to the print image generation unit 12c for steps S130 and S140. As indicated by the dashed arrow in Figure 3, after starting to capture an image of the fabric 30 in step S110, the control unit 11 repeats steps S120 to S140 in accordance with the captured image data sequentially obtained from the imaging unit 15. Therefore, in step S126, the pattern extraction unit 12b outputs information about the pattern area from the boundary line set in step S125 to the boundary line set in step S125 in the previous step S120 to the print image generation unit 12c.

[0040] A specific example of steps S121 to S126 will be described with reference to FIG. 6. Reference numeral 40 denotes an example of pattern image data 40. The pattern image data 40 is image data that expresses a pattern designed with a petal motif. Of course, such a pattern may be more complex. Reference numeral 41 denotes an example of captured image data 41. Within the captured image data 41, the range indicated by reference numeral 41a is a target region 41a that is set as a target region from which a pattern region is extracted. Similarly, within the captured image data 41, the range indicated by reference numeral 41b is a target region 41b, the range indicated by reference numeral 41c is a target region 41c, and the range indicated by reference numeral 41d is a target region 41d. Although not shown in the figure, such target regions are similarly repeatedly set upstream of the target region 41d.

[0041] The pattern extraction unit 12b sets target regions 41a, 41b, 41c, 41d, etc. as first and second regions within the captured image data 41. The length of each of the target regions 41a, 41b, 41c, 41d, etc. in the width direction D2 is the same as that of the captured image data 41, and the length of each of the target regions 41a, 41b, 41c, 41d, etc. is H×2. As can be seen from FIG. 6, the target region 41b, which is located upstream of the target region 41a, overlaps with the target region 41a by an OL distance (=H) in the conveying direction D1. Similarly, the target region 41c overlaps with the target region 41b by an OL distance in the conveying direction D1, and the target region 41d overlaps with the target region 41c by an OL distance in the conveying direction D1.

[0042] The overlapping area between target areas 41a and 41b is called OL area 41ab. Similarly, the overlapping area between target areas 41b and 41c is called OL area 41bc, and the overlapping area between target areas 41c and 41d is called OL area 41cd. When target area 41a is the first area, target area 41b corresponds to the second area. Similarly, when target area 41b is the first area, target area 41c corresponds to the second area. Similarly, when target area 41c is the first area, target area 41d corresponds to the second area. In the example of FIG. 6, H>A.

[0043] In step S120, which is the first step S120 performed after step S110, i.e., the first time step S120 is performed, the pattern extraction unit 12b sets the target region 41a as a first region in step S121, and extracts a pattern region from the target region 41a by comparing it with the pattern image data 40 in step S122. Then, in step S123, the pattern extraction unit 12b sets the target region 41b as a second region, and extracts a pattern region from the target region 41b by comparing it with the pattern image data 40 in step S124. The regions separated by dashed lines in the captured image data 41 are pattern regions 42 extracted by the pattern extraction unit 12b.

[0044] 6, the pattern region 42 extracted from the target region 41b (the second region) straddles the end 43a of the target region 41a (the first region). Therefore, in step S125, the pattern extraction unit 12b sets the boundary 44a of the pattern region 42 downstream of the end 43a or the boundary 44b of the pattern region 42 upstream of the end 43a as the boundary line. Here, for example, it is assumed that the boundary 44a is set as the boundary line. Then, in step S126, the pattern extraction unit 12b outputs information about the pattern region 42 extracted in the region downstream of the boundary line (boundary 44a) to the print image generation unit 12c, and the first round of step S120 ends.

[0045] In the second step S120, the pattern extraction unit 12b treats the target region 41b as the first region. However, the setting of the target region 41b and the extraction of the pattern region 42 from the target region 41b have already been completed in steps S123 and S124 of the first step S120. Therefore, the pattern extraction unit 12b regards the second extraction process already performed in the previous step S120 as the first extraction process in the current step S120, omits steps S121 and S122, sets the target region 41c as the second region in step S123, and extracts the pattern region 42 from the target region 41c in step S124. As shown in FIG. 6, the pattern region 42 extracted from the target region 41c as the second region straddles the end 43b of the target region 41b as the first region. Therefore, in step S125, the pattern extraction unit 12b sets a boundary 44c of the pattern region 42 downstream of the end 43b or a boundary 44d of the pattern region 42 upstream of the end 43b as the boundary line. Here, for example, it is assumed that the boundary 44c is set as the boundary line. Then, in step S126, the pattern extraction unit 12b outputs information about the pattern region 42 extracted in the region downstream from the boundary line (boundary 44c), that is, the region from boundary 44c to the boundary line (boundary 44a) set in the previous step S120, to the print image generation unit 12c, and the second step S120 ends.

[0046] The process is similar thereafter, but in the third iteration of step S120, the pattern extraction unit 12b treats the target region 41c as the first region, skips steps S121 and S122, sets the target region 41d as the second region in step S123, and extracts the pattern region 42 from the target region 41d in step S124. According to FIG. 6, the pattern region 42 extracted from the target region 41d as the second region straddles the end 43c of the target region 41c as the first region. Therefore, in step S125, the pattern extraction unit 12b sets, for example, the boundary 44e of the pattern region 42 upstream of the end 43c as the boundary line. Then, in step S126, the pattern extraction unit 12b outputs information about the pattern region 42 extracted in the region from the boundary line (boundary 44e) to the boundary line (boundary 44c) set in the previous step S120 to the print image generation unit 12c, thereby ending the third iteration of step S120.

[0047] According to step S120, the pattern extraction unit 12b may extract a pattern region from the same position in the captured image data by both the first extraction process and the second extraction process. For example, as shown in FIG. 6, each pattern region 42 sandwiched between boundary 44b and boundary 44c in the captured image data 41 is extracted by both the extraction process from target region 41b and the extraction process from target region 41c. However, as described above, the pattern extraction unit 12b outputs information about the pattern region 42 from the boundary line set in step S125 to the boundary line set in step S125 of the previous step S120 to the print image generation unit 12c. Therefore, the pattern extraction unit 12b provides the print image generation unit 12c with information about either the pattern region 42 extracted from the same position by the first extraction process or the pattern region 42 extracted from the same position by the second extraction process.

[0048] Returning to the explanation of Figure 3. In step S130, the print image generation unit 12c corrects the colored image data, which represents the image to be printed over the pattern on the fabric 30, so that it matches the shape of the pattern area extracted in step S120. The colored image data corresponds to "third image data." The colored image data is pre-generated color image data that represents the colors to be used in a single pattern and the color printing range. The colored image data is stored in advance in, for example, the storage unit 18. Alternatively, the control unit 11 inputs colored image data stored in a PC, for example, from an external PC to the printing device 10, in accordance with a user's operation, and stores the input colored image data in the storage unit 18.

[0049] The shape of the colored image data is the ideal shape of a pattern area having one pattern, for example, a rectangle. On the other hand, the shape of each pattern area extracted from the captured image data in step S120 is basically a rectangle, but it does not necessarily match the shape of the colored image data. This is because the fabric 30 being conveyed may be distorted or stretched (hereinafter referred to as "distortion, etc."). Although not specifically depicted in FIG. 6, each pattern area 42 extracted from the captured image data 41 may have a distorted or stretched shape due to distortion, etc. of the fabric 30.

[0050] Therefore, the print image generation unit 12c deforms the shape of the colored image data to match the individual shapes of the pattern regions extracted in step S120. Examples of the deformation method include affine transformation, which includes image enlargement, reduction, rotation, and shearing, as well as other deformation methods. This deformation is the correction performed in step S130. According to FIG. 6, the boundaries set in the captured image data 41 in step S125 are interpreted as straight lines perpendicular to the conveying direction D1. However, depending on the shape of each extracted pattern region 42, these boundaries may be straight lines that intersect obliquely with the conveying direction D1, or may even be broken lines. Depending on the shape of the pattern region 42, the correction performed in step S130 may not be necessary.

[0051] In step S140, the print image generation unit 12c generates print image data by arranging the multiple colored image data that have undergone step S130 in accordance with the arrangement of the multiple pattern areas in the captured image data. The print image data is image data obtained by combining the multiple colored image data that have undergone step S130, and is an image to be printed on the area of ​​the fabric 30 that was the subject of the image capture. Steps S130 and S140 correspond to a "print image generation process" that generates print image data by arranging the third image data to match the extracted pattern areas.

[0052] Specific examples of steps S130 and S140 based on the explanation of FIG. 6 will be described with reference to FIG. 7. Reference numeral 50 denotes an example of colored image data 50. The colored image data 50 may be interpreted as an image of the same or approximately the same size as the pattern image data 40. Reference numeral 51a denotes colored image data 51a obtained after the colored image data 50 has been corrected to fit the shape of one pattern region 42 downstream from the boundary 44a (the leftmost in FIG. 6), as indicated by the information provided by the pattern extraction unit 12b in step S126 of the first iteration of step S120. Similarly, reference numeral 51b denotes colored image data 51b obtained after the colored image data 50 has been corrected to fit the shape of a pattern region 42 downstream from the boundary 44a and adjacent in the width direction D2 to the pattern region 42 to which the colored image data 51a corresponds. Similarly, symbol 51c indicates the colored image data 51c after the colored image data 50 has been corrected to match the shape of the pattern area 42 downstream from the boundary 44a and adjacent in the width direction D2 to the pattern area 42 to which the colored image data 51b corresponds.

[0053] The colored image data 51a, 51b, 51c, etc. are combined in the order of the pattern areas 42 downstream from the boundary 44a to form the print image data 51. In other words, the print image data 51 is print image data generated by arranging the colored image data 50 so that it fits each of the pattern areas 42 extracted in the first step S120.

[0054] Similarly, the print image data 52 is print image data generated by arranging the colored image data 50 to fit each pattern area 42 located in the area from boundary 44c to boundary 44a, extracted in the second step S120. The print image data 53 is print image data generated by arranging the colored image data 50 to fit each pattern area 42 located in the area from boundary 44e to boundary 44c, which was extracted in the third step S120.

[0055] In step S150, the print control unit 12d starts printing the print image data generated in step S140 onto the fabric 30. In other words, step S150 starts the "printing process." Referring to the example in FIG. 7, the print image generation unit 12c, which repeats steps S130 and S140 to generate print image data 51, 52, 53, ..., outputs the print image data 51, 52, 53, ... to the print control unit 12d in the order in which they were generated. The print control unit 12d then applies necessary processes, such as color conversion and halftone processing, to the print image data acquired from the print image generation unit 12c, converting it into print image data in a format used by the printing unit 17 for printing. The print control unit 12d may temporarily store the converted print image data in a buffer.

[0056] The print control unit 12d then transfers the converted print image data to the print unit 17, and at a predetermined timing when the position of the fabric 30, for which imaging was started in step S110, reaches under the print head 19, causes the print unit 17 to start printing by moving the carriage 20 and discharging ink from the print head 19 based on the print image data. As a result, the color images expressed by the individual color image data constituting the print image data are printed superimposed on the patterns on the fabric 30 in a form that matches the individual patterns.

[0057] The transport unit 16 is equipped with an encoder that detects the amount of rotation of the rollers and belts that rotate for transport. The print control unit 12d calculates the transport distance of the fabric 30 based on the detection signal from the encoder. Therefore, the print control unit 12d determines the current position in the transport direction D1 of the fabric 30 where imaging began in step S110, and can cause the print unit 17 to start printing on the fabric 30 when that position reaches under the print head 19.

[0058] After printing starts in step S150, the control unit 11 determines whether or not to end printing (step S160). If printing is to end, the control unit 11 determines "Yes" and proceeds to the end processing of step S170. The control unit 11 determines that printing is ended, for example, when an instruction to end printing is received from the user or when the transport of the planned length of fabric 30 has been completed.

[0059] In the termination process of step S170, the control unit 11 stops the imaging unit 15 from capturing images of the fabric 30. After the control unit 11 causes the printing unit 17 to execute printing based on the print image data generated in the final cycle of steps S120 to S140, the control unit 11 stops driving the conveying unit 16 and the printing unit 17, and ends the flowchart of Fig. 3. Of course, the control unit 11 may stop the conveying unit 16 after controlling necessary processes such as the collection of the fabric 30 by the winding roller.

[0060] 3. Summary: According to this embodiment, the printing device 10 includes a conveying unit 16 that conveys the fabric 30 on which a pattern is formed in the conveying direction D1, an imaging unit 15 that images the fabric 30 conveyed by the conveying unit 16, a printing unit 17 that prints on the fabric 30 conveyed by the conveying unit 16, a pattern extraction unit 12b that extracts a pattern region 42 corresponding to the pattern in first image data based on a comparison between first image data representing the pattern and second image data generated by the imaging unit 15 capturing the image of the fabric 30, a print image generation unit 12c that generates print image data by arranging third image data representing an image to be printed over the pattern so that it matches the extracted pattern region 42, and a print control unit 12d that causes the printing unit 17 to print the print image data on the fabric 30. The pattern extraction unit 12b executes a first extraction process that extracts the pattern region 42 from a first region of the second image data and a second extraction process that extracts the pattern region 42 from a second region of the second image data. A part of the second area is an OL area that overlaps with the first area, and the length of the OL area in the transport direction D1, that is, the OL distance, is equal to or greater than the length A of the first image data in the transport direction D1.

[0061] According to the above configuration, the pattern extraction unit 12b overlaps the first region to be subjected to the first extraction process and the second region to be subjected to the second extraction process by the OL distance in the conveying direction D1. As a result, even if a pattern region that straddles the end of the first region cannot be extracted in the first extraction process, it is always included in the second region and can be extracted in the second extraction process. This prevents omissions of pattern regions from being extracted from the second image data. A specific description will be given with reference to FIG. 6. For example, when attempting to extract a pattern region 42 from the target region 41c, the pattern regions 42 that straddle the end 43c of the target region 41c cannot be extracted. However, if the target region 41d, which overlaps the target region 41c by the OL distance (= H) in the conveying direction D1, is selected as the extraction target for the pattern region 42, the pattern regions 42 that straddle the end 43c can be extracted.

[0062] Furthermore, according to this embodiment, when a pattern area 42 is extracted from the same position in the second image data by each of the first extraction process and the second extraction process, the pattern extraction unit 12b provides information on either the pattern area 42 extracted from the same position by the first extraction process or the pattern area 42 extracted from the same position by the second extraction process to the print image generation unit 12c for generating print image data. This configuration makes it possible to avoid repeatedly providing information about the same pattern area 42 to the print image generating unit 12c, thereby preventing the same image represented by the third image data from being printed multiple times on top of one pattern on the fabric 30.

[0063] Furthermore, according to this embodiment, after the second extraction process, the pattern extraction unit 12b sets a boundary line in the first region or the second region that is oriented in a direction that intersects with the conveying direction D1 and corresponds to the boundary between the extracted pattern regions 42, and provides information on the pattern regions 42 in the region downstream of the boundary line in the conveying direction D1 to the print image generation unit 12c for generating print image data. According to the above configuration, information on the pattern area 42 that has been extracted at the time the second extraction process is completed is provided to the print image generation unit 12c, so that the print image generation unit 12c does not miss any pattern area 42.

[0064] Furthermore, according to this embodiment, the pattern extraction unit 12b sets the length of the first region in the conveying direction D1 and the length of the second region in the conveying direction D1 to twice the OL distance. According to the above configuration, the pattern extraction unit 12b can extract a pattern region from each position in the second image data twice.

[0065] However, as long as the OL distance is equal to or greater than the length A of the first image data in the transport direction D1, the length of the first region in the transport direction D1 and the length of the second region in the transport direction D1 are not limited to twice the OL distance. For example, the pattern extraction unit 12b may set the length of the first region in the transport direction D1 and the length of the second region in the transport direction D1 to three times the OL distance. Furthermore, the pattern extraction unit 12b may set the length of the first region in the transport direction D1 and the length of the second region in the transport direction D1 to 1.5 times the OL distance. Needless to say, the length of the first region in the transport direction D1 and the length of the second region in the transport direction D1 are each longer than the OL distance.

[0066] In addition to the printing device 10, the present embodiment also discloses inventions in various categories, such as systems, programs, and methods. The printing method includes a conveying step of conveying fabric 30 on which a pattern has been formed in a conveying direction D1, an imaging step of imaging the conveyed fabric 30, a pattern extraction step of extracting a pattern region 42 corresponding to the pattern in second image data based on a comparison between first image data representing the pattern and second image data generated by imaging the fabric 30, a print image generation step of generating print image data by arranging third image data representing an image to be printed over the pattern so that it matches the extracted pattern region 42, and a printing step of printing the print image data on the conveyed fabric 30. The pattern extraction step executes a first extraction process of extracting the pattern region 42 from a first region of the second image data and a second extraction process of extracting the pattern region 42 from a second region of the second image data. A portion of the second region is an OL region that overlaps with the first region, and the length of the OL region in the conveying direction D1, i.e., the OL distance, is equal to or greater than the length A of the first image data in the conveying direction D1.

[0067] 4.Other explanations: The pattern extraction unit 12b can change the OL distance according to the length A of the first image data in the conveying direction D1. For example, if the length A of the pattern image data 40 in the conveying direction D1 is multiplied by a predetermined coefficient α (where α≧1) to define H as the OL distance, and the length of the first region in the conveying direction D1 and the length of the second region in the conveying direction D1 are each defined as H×2, then the pattern extraction unit 12b will change the OL distance and the sizes of the first region and the second region according to the length A.

[0068] Alternatively, the pattern extraction unit 12b determines A1×α×2 as the fixed length in the conveying direction D1 of each of the first and second regions, using the maximum value A1 expected for the length A as a reference. Then, the pattern extraction unit 12b may set the OL distance as A×α in accordance with the length A of the actual pattern image data 40. With this configuration, it is possible to change the area of ​​the OL region between the first and second regions in accordance with the length A, without changing the size of each of the first and second regions.

[0069] 2A discloses a so-called serial printer configuration in which the print head 19 is mounted on a carriage 20 and moves, but the print head 19 may also be a so-called line-type head. In other words, the print head 19 may be a long print head that is not mounted on a carriage 20 and can cover the width of the fabric 30 along the width direction D2.

[0070] 2A and 2B, the component designated by the reference numeral 22 may not be an endless belt, but may be a platen that serves as a platform supporting the fabric 30 from below. In other words, it may be understood that the fabric 30, transported by rollers (not shown), moves on the platen. This embodiment can also be applied to the case where a material other than the fabric 30, for example, a paper print medium on which a pattern is formed, is used for printing. [Explanation of symbols]

[0071] 10...printing device, 11...control unit, 12...program, 12a...pattern registration unit, 12b...pattern extraction unit, 12c...print image generation unit, 12d...printing control unit, 13...display unit, 14...operation reception unit, 15...imaging unit, 16...conveying unit, 17...printing unit, 18...storage unit, 19...print head, 20...carriage, 22...endless belt, 30...fabric, 40...pattern image data, 41...captured image data, 41a, 41b, 41c, 41d...target area, 42...pattern area, 44a, 44b, 44c, 44d, 44e...boundary, 50, 51a, 51b, 51c...colored image data, 51, 52, 53...printing image data

Claims

1. a conveying unit that conveys the fabric on which the plurality of patterns are formed in a conveying direction; an imaging unit that images the fabric conveyed by the conveying unit; a printing unit that prints on the fabric conveyed by the conveying unit; a pattern extraction unit that extracts a pattern area corresponding to one of the patterns in the second image data based on a comparison between first image data representing one of the plurality of patterns and second image data generated by the imaging unit capturing an image of the fabric; and a print image generating unit that generates print image data by arranging third image data representing an image to be printed over the one pattern so as to fit the extracted pattern area; a print control unit that causes the printing unit to print the print image data on the fabric, The pattern extraction unit a first extraction process for extracting the pattern region from a first region of the second image data; a second extraction process for extracting the pattern region from a second region of the second image data, the second extraction process being performed a plurality of times while changing the region in the transport direction; a part of the second region is an overlap region that overlaps with the first region, a length of the overlapping area in the transport direction is equal to or greater than a length of the first image data in the transport direction; a length of the first region in the conveying direction and a length of the second region in the conveying direction are set to be greater than one time and equal to or less than two times a length of the overlap region in the conveying direction; the first region that is a target of the first extraction process in the second pattern extraction step is the second region that is a target of the second extraction process in the first pattern extraction step, A printing device characterized in that the overlap area set in the first extraction process and the second extraction process and the overlap area set in the second extraction process are adjacent to each other in the transport direction or overlap each other in the transport direction.

2. A printing device as described in claim 1, characterized in that the length of the first region in the conveying direction and the length of the second region in the conveying direction are 1.5 or 2 times the length of the overlap region in the conveying direction.

3. The printing device described in claim 1 or 2, characterized in that when the pattern extraction unit extracts the pattern area from the same position in the second image data by each of the first extraction process and the second extraction process, it provides information on either the pattern area extracted from the same position by the first extraction process or the pattern area extracted from the same position by the second extraction process to the print image generation unit for generating the print image data.

4. The pattern extraction unit After the second extraction process, a boundary line is set in the first region or the second region, the boundary line being a line that intersects with the transport direction and corresponds to a boundary between the extracted pattern regions; A printing device as described in any one of claims 1 to 3, characterized in that information on the pattern area in the area downstream of the boundary line in the transport direction is provided to the print image generation unit for generating the print image data.

5. 5. The printing device according to claim 1, wherein the pattern extraction unit changes the length of the overlap region in the transport direction in accordance with the length of the first image data in the transport direction.

6. a conveying step of conveying the fabric on which the plurality of patterns are formed in a conveying direction; an imaging step of imaging the fabric being conveyed; a pattern extraction step of extracting a pattern area corresponding to one of the plurality of patterns in the second image data based on a comparison between first image data representing the one of the plurality of patterns and second image data generated by capturing an image of the fabric; a print image generating step of generating print image data by arranging third image data representing an image to be printed over the one pattern so as to fit the extracted pattern area; a printing step of printing the print image data on the transported fabric, The pattern extraction step includes: a first extraction process for extracting the pattern region from a first region of the second image data; a second extraction process for extracting the pattern region from a second region of the second image data, the second extraction process being performed a plurality of times while changing the region in the transport direction; a part of the second region is an overlap region that overlaps with the first region, a length of the overlapping area in the transport direction is equal to or greater than a length of the first image data in the transport direction; a length of the first region in the conveying direction and a length of the second region in the conveying direction are set to be greater than one time and equal to or less than two times a length of the overlap region in the conveying direction; A printing method characterized in that the overlap area set in a first round of the first extraction process and the second extraction process and the overlap area set in a second round of the first extraction process and the second extraction process are adjacent in the transport direction or overlap in the transport direction.

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