Image processing method, image processing device, printing system, and image processing program

Abstract

To improve the operability of a user.SOLUTION: An image processing method includes the steps of: displaying, on a display device, a preview image representing a virtual three-dimensional object of printed matter in which one or more printing layers and a printing medium are superimposed and combined in the stacking order, the preview image corresponding to appearance in a three-dimensional virtual space; receiving a change instruction to change the appearance of the three-dimensional object; changing at least one of a posture of the three-dimensional object in the virtual space and a viewpoint position and a viewing direction of a virtual camera with respect to the three-dimensional object in the virtual space so that the appearance of the three-dimensional object is changed in accordance with the change instruction, and displaying the preview image representing the three-dimensional object after the change on the display device; and displaying, on the display device, together with the preview image, display information indicating the appearance of the three-dimensional object represented by the preview image that is currently being displayed.SELECTED DRAWING: Figure 14

Description

[Technical Field]

[0001] The present disclosure relates to an image processing method, an image processing device, a printing system, and an image processing program. [Background technology]

[0002] Patent Document 1 describes a technology for displaying preview images showing the front and back sides of a print medium after printing when printing on a transparent medium. In the technology described in Patent Document 1, when a user instructs to display a preview image of the front or back side of the print medium that is different from the side currently displayed as a preview image, the display of the preview image is switched. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-201264 Summary of the Invention [Problem to be solved by the invention]

[0004] When printing on a transparent medium, the printed image can be seen from the back side as well. Therefore, as users repeatedly switch between the preview screen for the front side and the preview screen for the back side, it is expected that it will become difficult for users to determine whether the currently displayed side is the front side or the back side. For this reason, technology with good operability for users has been desired. [Means for solving the problem]

[0005] The present disclosure can be realized in the following forms.

[0006] According to a first aspect of the present disclosure, there is provided an image processing method, including: (a) receiving one or more print layers to be stacked on a print medium by printing on the print medium and a stacking order of the print media; (b) displaying, on a display device, a preview image representing a virtual three-dimensional object of a printed matter formed by stacking the one or more print layers and the print medium in the stacking order, the preview image corresponding to how the object will appear in a three-dimensional virtual space; (c) receiving a change instruction to change the appearance of the three-dimensional object; (d) changing, in accordance with the change instruction, at least one of an orientation of the three-dimensional object in the virtual space and a viewpoint position and a line of sight direction of a virtual camera relative to the three-dimensional object in the virtual space so as to change the appearance of the three-dimensional object, and displaying, on the display device, the preview image representing the changed three-dimensional object; and (e) displaying, on the display device, display information indicating how the three-dimensional object will appear in the currently displayed preview image.

[0007] According to a second aspect of the present disclosure, there is provided an image processing device including: a print setting receiving unit that receives one or more printing layers to be laminated on a printing medium by printing on the printing medium and a layering order of the printing media; a display processing unit that displays, on a display device, a preview image representing a virtual three-dimensional object of a printed matter formed by laminating the one or more printing layers and the printing medium in the layering order, the preview image corresponding to how the object will appear in a three-dimensional virtual space; and a change receiving unit that receives a change instruction to change the appearance of the three-dimensional object, wherein, when the change receiving unit receives the change instruction, the display processing unit changes at least one of an orientation of the three-dimensional object in the virtual space and a viewpoint position and a line of sight direction of a virtual camera relative to the three-dimensional object in the virtual space so as to change the appearance of the three-dimensional object in accordance with the change instruction, and displays, on the display device, a preview image representing the three-dimensional object after the change and display information indicating how the three-dimensional object will appear in the preview image after the change.

[0008] According to a third aspect of the present disclosure, there is provided a printing system. The printing system includes an image processing device, a printing device, and a display device. The image processing device includes a print setting receiving unit that receives one or more printing layers to be stacked on a print medium by printing on the print medium and a stacking order of the printing media; a display processing unit that displays, on the display device, a preview image representing a virtual three-dimensional object of a printed matter in which the one or more printing layers and the print medium are stacked in the stacking order, the preview image corresponding to how the object will appear in a three-dimensional virtual space; and a change receiving unit that receives a change instruction to change the appearance of the three-dimensional object. When the change receiving unit receives the change instruction, the display processing unit changes at least one of the orientation of the three-dimensional object in the virtual space and the viewpoint position and line of sight of a virtual camera relative to the three-dimensional object in the virtual space so that the appearance of the three-dimensional object is changed in accordance with the change instruction, and displays, on the display device, a preview image representing the three-dimensional object after the change and display information indicating how the three-dimensional object will appear in the preview image after the change.

[0009] According to a fourth aspect of the present disclosure, there is provided an image processing program that causes a computer to (a) receive one or more printing layers to be stacked on a printing medium by printing on the printing medium and a stacking order of the printing media, (b) display on a display device a preview image representing a virtual three-dimensional object of a printed matter formed by stacking the one or more printing layers and the printing medium in the stacking order, the preview image corresponding to how the object will appear in a three-dimensional virtual space, (c) receive a change instruction to change the appearance of the three-dimensional object, (d) change at least one of the orientation of the three-dimensional object in the virtual space and the viewpoint position and line of sight of a virtual camera relative to the three-dimensional object in the virtual space in response to the change instruction so as to change the appearance of the three-dimensional object, and display on the display device the preview image representing the changed three-dimensional object, and (e) display information indicating how the three-dimensional object will appear in the currently displayed preview image together with the preview image. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a block diagram illustrating a schematic configuration of a printing system according to an embodiment. [Figure 2] FIG. 1 is an explanatory diagram showing a printed matter in which an image is printed on a transparent printing medium. [Figure 3] FIG. 10 is an explanatory diagram showing another example of a printed matter in which an image is printed on a transparent printing medium. [Figure 4] FIG. 1 is an explanatory diagram illustrating a configuration of an image processing device. [Figure 5] FIG. 2 is an explanatory diagram showing an example of a user interface for inputting image data. [Figure 6] FIG. 2 is an explanatory diagram of an input operation in a user interface. [Figure 7] FIG. 2 is an explanatory diagram illustrating processing of a preprocessing unit. [Figure 8] FIG. 2 is an explanatory diagram illustrating processing of a preprocessing unit. [Figure 9] FIG. 2 is an explanatory diagram illustrating the configuration of a rendering unit. [Figure 10] 4 is a flowchart showing a printing process executed in the image processing apparatus. [Figure 11] FIG. 10 is an explanatory diagram schematically showing how the surface of a printed matter expressed as a three-dimensional object in a virtual space is observed. [Figure 12] FIG. 10 is an explanatory diagram schematically illustrating the state of observing the back side of a printed matter represented as a 3D object in a virtual space. [Figure 13] 10 is a flowchart showing a display switching process. [Figure 14] FIG. 10 is an explanatory diagram showing a state in which the image processing device re-displays a rendering image in response to a touch operation. [Figure 15] FIG. 10 is an explanatory diagram of the effect of the present embodiment. [Figure 16] 10 is an explanatory diagram showing a mode in which display information is displayed according to another first embodiment. FIG. [Figure 17] 10 is a flowchart showing a display switching process according to another embodiment 2. [Figure 18] FIG. 10 is an explanatory diagram showing an example of a display mode of a preview image according to another embodiment 2. [Figure 19] FIG. 1 is an explanatory diagram showing the positional relationship between a virtual object representing a printed matter and a camera placed in a virtual space. [Figure 20] FIG. 10 is an explanatory diagram of a user interface according to another fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] A. Implementation: 1 is a block diagram showing a schematic configuration of a printing system 10 according to this embodiment. The printing system 10 includes an image processing device 100, an input device 200, a display device 300, and at least one printing device 400. The printing system 10 functions as a printing device in the broad sense.

[0012] The image processing device 100 generates a rendering image corresponding to how a printed matter will appear in a three-dimensional virtual space by using physics-based rendering (hereinafter simply referred to as rendering). Before printing, the image processing device 100 displays the generated rendering image as a preview image on the display device 300. In this embodiment, the appearance of a printed matter in a three-dimensional virtual space is determined by the orientation of a three-dimensional object in the virtual space, or the viewpoint position and line of sight of a virtual camera relative to the three-dimensional object in the virtual space. A user can view a 3D object representing the printed matter in the virtual space from the viewpoint position and line of sight of a virtual camera.

[0013] The printing device 400 is an inkjet printing device that prints an image directly onto a print medium. In this embodiment, the printing device 400 prints an image onto a transparent print medium. The print medium has a flat plate shape. The print medium can be a transparent film or sheet made of a material such as polypropylene (PP), polyethylene (PET), or polyvinyl chloride (PVC). Alternatively, the print medium can be a transparent plate made of a material such as acrylic or glass. However, the print medium may also be translucent. A transparent print medium may have, for example, an average visible light transmittance of 80% or more. Alternatively, a translucent print medium may have, for example, an average visible light transmittance of 30% or more but less than 80%. In this embodiment, processing when a transparent print medium is used will be described. Substantially the same processing can be applied whether a translucent print medium or an opaque print medium is used.

[0014] In addition to front printing, the printing device 400 can also perform reverse printing. Front printing refers to printing on the front side of a print medium. In this specification, the front side of a print medium refers to the side on which the printed matter is expected to be observed. The reverse side is the side opposite the front side. Reverse printing refers to printing an image on the reverse side of a transparent print medium with the image orientation and printing order reversed. The reverse-printed image can be seen through the transparent print medium. Reverse printing makes it possible to obtain printed matter with a transparent or glossy appearance. Below are some examples of front and reverse printing.

[0015] FIG. 2 is an explanatory diagram showing a printed matter PT1 in which an image is printed on a transparent printing medium. In the printed matter PT1, a color layer CL in which a front image SG is formed is formed on the surface of the transparent printing medium PM. The printed matter PT1 is printed by surface printing. The color layer CL is formed by printing plates of each process color. The color layer CL is formed by a collection of dots of process ink. The thickness of the layer is exaggerated for convenience of illustration. The printed matter PT1 is intended to be observed only from the front side, but when observed from the back side, a back image RG, which is a left-right inverted image of the front image SG, can be seen. A left-right inverted image is also called a mirror-inverted image.

[0016] 3 is an explanatory diagram showing another example of a printed matter in which an image is printed on a transparent printing medium, in which the thickness of layers is exaggerated for convenience of illustration.

[0017] In the printed matter PT2 in Figure 3, a color layer CL that forms a back-side image RG is printed on the back side of a transparent printing medium PM. The printed matter PT2 is printed by reverse printing. Figure 3 shows the printed matter PT2 positioned so that the back side of the printing medium PM is facing up. Because the printing medium PM is transparent, when viewed from the front side, the front-side image SG, which is a left-right inverted image of the back-side image RG, can be seen through the printing medium PM.

[0018] As shown in FIG. 1, the image processing device 100 is a computer including a memory 101, an input / output interface 102, a processor 103, and an internal bus 104. The memory 101, the input / output interface 102, and the processor 103 are communicatively connected via the internal bus 104. The memory 101 stores various programs and data used for various processes executed by the image processing device 100. The memory 101 stores a program PG. An input device 200, a display device 300, and a printing device 400 are connected to the input / output interface 102 via wired or wireless communication. The processor 103 realizes various functions by executing the programs stored in the memory 101. The input device 200 is, for example, a keyboard or a mouse. The display device 300 is, for example, a liquid crystal display or an organic EL (Electro Luminescence) display. In this embodiment, the display device 300 further functions as a pointing device.

[0019] 4 is an explanatory diagram showing the configuration of the image processing device 100. The image processing device 100 includes an image data acquisition unit 110, a profile acquisition unit 120, a printing condition acquisition unit 130, a parameter acquisition unit 140, a preprocessing unit 150, a rendering unit 160, an update reception unit 165, and a print data generation unit 170. The functions of these units are realized by the processor 103 executing a program PG stored in the memory 101 shown in FIG. 1. The rendering unit 160 is also called a "display processing unit."

[0020] 5 is an explanatory diagram showing an example of a user interface UI for inputting image data. The user interface UI is displayed on the display device 300 under the control of the processor 103. Here, an example will be described in which an acrylic plate is used as the printing medium PM.

[0021] The user interface UI is provided with a display area FM that displays the type of print medium PM, a button BT1 for adding a print layer to be overlaid on the front side of the print medium PM, a button BT2 for adding a print layer to be overlaid on the back side of the print medium PM, a display area FV1 that displays an image selected by the user, a display area FV2 for displaying a preview image, a button BT5 for selecting the image to be printed, and a print button BTP for instructing the start of printing. The print layer is a layer formed from ink.

[0022] When the user taps button BT1, a color layer can be added to be placed on the front surface of the acrylic plate serving as the printing medium PM. When the user taps button BT2, a color layer can be added to be placed on the rear surface of the acrylic plate serving as the printing medium PM. In this embodiment, to facilitate understanding of the technology, it is assumed that a color layer is placed on only one of the front and rear surfaces of the printing medium PM.

[0023] When the user taps the button BT5 in the display area FV1, a list (not shown) of image data stored in a predetermined area of ​​the memory 101 of the image processing device 100 is displayed. This allows the user to select desired image data. An image represented by the image data selected by the user is displayed in the display area FV1. Note that if no image data is selected, no image is displayed in the display area FV1.

[0024] Fig. 6 is an explanatory diagram of input operations in the user interface UI. Fig. 6 shows the user interface UI after the user has added a color layer and selected image data. In the illustrated example, a color layer has been added to the surface of an acrylic plate serving as the printing medium PM.

[0025] The user interface UI displays a button BT4 for deleting each color layer added by the user. The user can delete an added color layer by tapping the button BT4.

[0026] When image data for an added color layer is selected, a preview image is displayed in the display area FV2. By default, a preview image representing the front side of the printed material is displayed in the display area FV2. In this embodiment, a preview image representing the front side of the printed material or a preview image representing the back side of the printed material is displayed in the display area FV2. Furthermore, the display area FV3 displays display surface information indicating whether the preview image shows the front side or the back side of the printed material. By tapping the preview image displayed in the display area FV2, the user can instruct the display area FV3 to change the appearance of the printed material represented by the preview image displayed in the display area FV2. Upon receiving a user instruction, the rendering unit 160 (described later) updates the display of the rendered image displayed in the display area FV2.

[0027] 4, the image data acquisition unit 110 acquires image data selected by the user from a list (not shown) of image data stored in the memory 101 of the image processing device 100, which is displayed by tapping the button BT5. The selected image data is referred to as input image data IMi. The input image data IMi represents an image to be formed on the printing medium PM. The input image data IMi is sent to the pre-processing unit 150.

[0028] The profile acquisition unit 120 acquires an input profile IPF, a media profile MPF, and a common color space profile CPF that are stored in advance in the memory 101. Note that the input profile IPF, media profile MPF, and common color space profile CPF are not shown in FIG. 1. The input profile IPF, media profile MPF, and common color space profile CPF are used for color conversion by a color management system 151 of a pre-processing unit 150, which will be described later. Details of each profile will be described later. Each acquired profile is sent to the pre-processing unit 150. Note that the profile acquisition unit 120 may acquire each profile from an external server via a network (not shown).

[0029] The printing condition acquisition unit 130 acquires printing conditions. The printing conditions include the type of print medium, the type of printing, the layering order indicating the order in which the print medium and one or more print layers are layered, the type of ink for the print layers, the print resolution, the type of printing device, and other conditions. When the print medium has a flat shape, the layering order indicates the order in which the print medium and one or more print layers are layered with the front side of the print medium facing up. In the case of front-side printing, the layering order is, from the bottom, the print medium, then the print layer. In the case of reverse-side printing, the layering order is, from the bottom, the print layer, then the print medium. The printing conditions acquired by the printing condition acquisition unit 130 are sent to the profile acquisition unit 120, the parameter acquisition unit 140, and the preprocessing unit 150. The printing condition acquisition unit 130 is also referred to as the "print setting acceptance unit."

[0030] The parameter acquisition unit 140 acquires various parameters used for rendering from the memory 101. The various parameters are stored in advance in the memory 101. The various parameters used for rendering include, for example, three-dimensional object information (hereinafter referred to as 3D object information), camera information, lighting information, and medium parameters. The 3D object information is a parameter related to the shape of the print medium as a three-dimensional object (hereinafter referred to as 3D object) placed in virtual space. The camera information is a parameter related to the position and orientation of the camera placed in virtual space. The lighting information is a parameter related to the type, position, orientation, color, and luminous intensity (amount of light) of the light source placed in virtual space. The types of light source include, for example, fluorescent lamps and incandescent lamps.

[0031] The medium parameters are parameters related to the texture of the print medium. In this embodiment, the medium parameters include a texture parameter that represents the texture of the print medium and a translucency parameter that represents the translucency of the print medium. The texture parameters include, for example, a base color (Base Color) related to the background color of the print medium, smoothness (Smoothness) that represents the smoothness of the print medium, metallicity (Metallic) that represents the metallicity of the print medium, a normal map (Normal Map), and a height map (Height Map). High metallicity increases the likelihood that the surrounding scenery will be reflected in the print medium. Instead of smoothness, the texture parameters may also include roughness (Roughness) that represents the roughness of the print medium. The normal map and height map are used to represent minute irregularities in the print medium that affect light reflection. The normal map is a texture that represents the distribution of normal vectors of minutely irregular surfaces. The height map is a texture that represents the distribution of heights of minutely irregular surfaces. Reducing the size of the polygons that make up a 3D object to represent minute irregularities results in an enormous number of polygons, increasing the computational load of rendering. Using normal maps and height maps makes it possible to represent the effect of minute irregularities on light reflection without reducing the size of polygons. Translucency parameters include media transmittance, which represents the light transmittance (transparency) of the printing medium. Translucency parameters may also include media opacity, which represents the light opacity (opacity) of the printing medium.

[0032] The various parameters acquired by the parameter acquisition unit 140 are transmitted to the rendering unit 160. The parameter acquisition unit 140 may acquire the various parameters from an external server via a network (not shown).

[0033] The preprocessing unit 150 includes a color management system 151 and a medium color calculation unit 153. Hereinafter, the color management system 151 may be simply referred to as the CMS 151.

[0034] 7 is an explanatory diagram showing the processing content of the CMS 151. The CMS 151 uses each profile acquired by the profile acquisition unit 120 to execute various types of color conversion processing.

[0035] The input profile IPF is an ICC (International Color Consortium) profile used for color conversion from the color space of image data (input color space) to a device-independent color space. The input color space is, for example, the RGB color space. The device-independent color space is, for example, the CIE-L*a*b* color space. The media profile MPF is an ICC profile used for color conversion from the device-independent color space to a device-dependent color space for the printing device 400. The device-dependent color space for the printing device 400 is, for example, the CMYK color space. Colors in the device-dependent color space for the printing device 400 are also called device colors. The common color space profile is an ICC profile used for color conversion from the device-independent color space to a color space for rendering. The color space for rendering is, for example, sRGB, AdobeRGB, or Display-P3.

[0036] An example of color conversion processing executed by the CMS 151 is as follows: The CMS 151 executes the following color conversion processing in order on the input image data IMi. (1) A first color transformation CC1 from the input color space to a device-independent space using the input profile IPF. (2) A second color transformation CC2 from the device independent color space to the device dependent color space for the printing device 400 using the media profile MPF. (3) A third color transformation CC3 from a device-dependent color space to a device-independent color space for the printing device 400 using the media profile MPF. (4) A fourth color transformation CC4 from a device-independent color space to a rendering color space using the common color space profile CPF.

[0037] The first color conversion CC1 and the second color conversion CC2 convert the color values ​​of the image data into a range that can be represented by printing. In other words, the first color conversion CC1 and the second color conversion CC2 convert the color values ​​of the image data into color values ​​in a color space that depends on the printing device and the printing medium. The image data that has undergone the first color conversion CC1 and the second color conversion CC2 is called device color image data IMd. The device color image data IMd is sent to the print data generation unit 170 (see FIG. 4). For example, multiple input image data IMi may be prepared because images are printed on both sides of the printing medium PM. In this case, multiple device color image data IMd are obtained by performing color conversion on each input image data IMi.

[0038] As shown in FIG. 7, the third color conversion CC3 and the fourth color conversion CC4 convert the color values ​​of the image data into a range that can be represented by rendering. By applying the first color conversion CC1 to the fourth color conversion CC4, the color values ​​of the image data are converted into color values ​​in the rendering color space. The image data converted into color values ​​in the rendering color space is called rendering image data IMm. The rendering image data IMm is used as a texture to be added to the polygon representing the color layer CL in rendering. The RGBA values ​​of the base color of the color layer CL are set to (1,1,1,1). The rendering image data IMm is sent to the rendering unit 160 (see FIG. 4). Furthermore, for example, multiple input image data IMi may be input because images are printed on both sides of the printing medium PM. In this case, multiple pieces of rendering image data IMm are obtained by performing color conversion processing on each piece of input image data IMi.

[0039] 8 is an explanatory diagram showing the flow of color conversion processing. For the sake of convenience, multiple CMSs 151 are shown in FIG. 8, but these are the same CMS 151.

[0040] The medium color calculation unit 153 obtains YXZ values ​​representing the color of the print medium PM from the media profile MPF. The media profile MPF pre-stores XYZ values ​​representing the color of the print medium PM. The CMS 151 converts the XYZ values ​​Clx representing the color of the print medium PM into RGB values ​​using the common color space profile CPF. The medium color calculation unit 153 also obtains a medium transmittance α representing the light transmittance (transparency) of the print medium. The medium transmittance is included in the medium parameters obtained by the parameter acquisition unit 140. The medium color calculation unit 153 combines the RGB values ​​obtained by converting the XYZ values ​​Clx representing the color of the print medium PM with the medium transmittance α, and outputs the combined values ​​to the rendering unit 160 as an RGBA value representing the rendering medium color Clp.

[0041] The rendering unit 160 generates a rendered image that represents how a print medium with an image printed on it will look in virtual space. In the rendering, the printed material is represented as a 3D object in virtual space. The rendering unit 160 is also called a "display processing unit."

[0042] 9 is an explanatory diagram showing the configuration of the rendering unit 160. The rendering unit 160 employs a pipeline configuration including a vertex pipeline VPL, a rasterizer RRZ, a pixel pipeline PPL, and a post-processing unit. The vertex pipeline VPL includes a vertex shader VS and a geometry shader GS. The pixel pipeline PPL includes a pixel shader PS and a render backend RBE.

[0043] The vertex shader VS uses 3D object information, camera information, and lighting information to perform processing related to the polygons that make up the 3D object. This processing includes coordinate transformation of the vertices of each polygon that makes up the 3D object, calculation of the normal vectors of each polygon, shading, and calculation of texture mapping coordinates (UV coordinates). Coordinate transformations include model transformation, which is a coordinate transformation from the 3D object's local coordinate system to the world coordinate system, view transformation, which is a coordinate transformation from the world coordinate system to the view coordinate system, and projection transformation, which is a coordinate transformation from the view coordinate system to the screen coordinate system. Some of the above coordinate transformations may be performed by the geometry shader GS. The processing results of the vertex shader VS are sent to the geometry shader GS.

[0044] The geometry shader GS processes a set of vertices of a 3D object. The geometry shader GS can convert polygons into points and lines, and convert points or lines into polygons, by increasing or decreasing the number of vertices. The processing results of the geometry shader GS are sent to the rasterizer RRZ. Note that the rendering unit 160 does not necessarily need to be provided with a geometry shader GS. In this case, the processing results of the vertex shader VS are sent to the rasterizer RRZ.

[0045] The rasterizer RRZ performs rasterization processing to generate drawing information for each pixel from the processing results of the vertex pipeline VPL. The processing results of the rasterizer RRZ are sent to the pixel shader PS.

[0046] The pixel shader PS performs lighting processing using the rasterized 3D object, image data, and material parameters to calculate the colors of the front and back polygons corresponding to each pixel. The Disney principle BRDF (Bidirectional Reflectance Distribution Function) can be used as a function to calculate the reflection of light during lighting processing. The processing results of the pixel shader PS are sent to the render backend RBE.

[0047] The render backend RBE determines whether to write pixel data generated by the pixel shader PS to the display area of ​​the memory 101. If the render backend RBE determines to write to the memory 101, the pixel data is saved as a drawing target. If the render backend RBE does not determine to write to the memory 101, the pixel data is not saved as a drawing target. The determination of whether to write is made using, for example, an alpha test, a depth test, or a stencil test. In this embodiment, the pixel data includes color information of front-facing polygons and color information of back-facing polygons. The render backend RBE writes the colors of polygon objects from the farthest side to the camera, for example, using a depth sorting method. After writing the color of the farthest polygon object, when writing the color of the nearer polygon, the render backend RBE combines the color of the farther polygon with the color of the nearer polygon, for example, using alpha blending, depending on the transparency of the nearer polygon. If the transparency is zero, the color of the polygon in the foreground is overwritten by the color of the polygon in the background when the color of the polygon in the foreground is written. This process of writing to the display area is also called the "drawing process." Pipeline processing ends when the pixel data is written to memory 101.

[0048] The post-processing unit PST performs post-processing such as anti-aliasing, ambient occlusion, screen space reflection, and depth of field processing on the rendered image made up of pixel data stored in the memory 101. Post-processing improves the appearance of the rendered image.

[0049] The update receiving unit 165 receives an instruction to update the display of a rendering image that represents a printed matter expressed as a 3D object in a virtual space. Specifically, the update receiving unit 165 receives a change instruction to change the appearance of a 3D object indicated by a touch operation on the rendering image as a preview image displayed in the display area FV2 of the user interface UI (see FIG. 5). The update receiving unit 165 outputs the received change instruction to the rendering unit 160. The update receiving unit 165 is also referred to as a "change receiving unit."

[0050] The print data generation unit 170 generates print data to be supplied to the printing device 400. The print data generation unit 170 includes a setting unit 171, a plate separation unit 173, and a halftone processing unit 175.

[0051] The setting unit 171 determines whether or not left-right flipping of the image to be printed is necessary depending on the printing conditions. Specifically, when "reverse printing" is selected as the type of printing, the setting unit 171 determines that left-right flipping of the image to be printed is necessary. When "front printing" is selected as the type of printing, the setting unit 171 determines that left-right flipping of the image to be printed is not necessary.

[0052] If left-right reversal processing is required, that is, if reverse printing is specified, the setting unit 171 performs left-right reversal processing of the device color image data IMd obtained by the color conversion processing of the CMS 151. On the other hand, if front printing is specified, reversal processing is not performed.

[0053] Furthermore, when forming multiple print layers, the setting unit 171 determines the order in which the print layers are to be stacked. Specifically, depending on the printing conditions, the setting unit 171 determines the placement positions (placement surfaces) at which the print layers are to be placed on the print medium, and the stacking order in which the multiple print layers are to be stacked when there are multiple print layers.

[0054] The plate separating unit 173 converts the output value of each pixel of the device color image data IMd, which may or may not have been subjected to left-right flipping, into density values ​​of multiple color materials of the printing device 400. In this embodiment, the plate separating unit 173 converts the CMYK output value of each pixel of the device color image data IMd into density values ​​of each color of process ink. Each plate of CMYKLcLm is generated by the processing of the plate separating unit 173. Note that when printing is performed on both sides of the printing medium PM, the plate separating unit 173 generates each plate of CMYKLcLm for each of the front and back surfaces of the printing medium PM.

[0055] The halftone processing unit 175 generates print data by performing halftone processing using the density values ​​of each pixel after color separation. The printing device 400 receives the print data sent from the halftone processing unit 175 and executes printing based on the printing conditions included in the received print data. Note that when printing is performed on both sides of the print medium PM, the halftone processing unit 175 generates print data for both the front and back sides of the print medium PM.

[0056] 10 is a flowchart showing a printing process executed in the image processing device 100. The process in FIG.

[0057] In step S10, input image data IMi and printing conditions are acquired. Specifically, first, a user interface UI (see FIG. 5) is displayed on the display device 300. Then, image data (input image data IMi) specified by a user through input via the user interface UI is acquired. Then, information indicating the printing conditions input by the user through the user interface UI is acquired. The printing conditions include conditions indicating which of the front and back surfaces of the printing medium PM the color layer will be overlaid on.

[0058] In step S20, preprocessing is performed by each unit of the preprocessing unit 150. The contents of the preprocessing are as shown in FIG. 9. Through the preprocessing, device color image data IMd, rendering image data IMm, and rendering medium color Clp are generated. The device color image data IMd is sent to the print data generation unit 170. The rendering image data IMm and rendering medium color Clp are sent to the rendering unit 160.

[0059] In step S30, the rendering image generated by the rendering unit 160 is displayed as a preview image on the display device 300. The processing by the rendering unit 160 is as shown in FIG. 9. In step S40, the print data generation unit 170 generates print data. In step S50, the print data is sent to the printing device 400. The above is a series of processes related to printing executed in the image processing device 100.

[0060] In this embodiment, the image processing device 100 displays a rendering image as a preview image. FIG. 11 is an explanatory diagram that shows a schematic view of the front side of a printed matter represented as a 3D object in a virtual space. FIG. 12 is an explanatory diagram that shows a schematic view of the back side of a printed matter represented as a 3D object in a virtual space. Here, as shown in FIG. 2, an example of a printed matter printed on the front side of a printing medium PM by front printing is shown. The printed matter is represented as a 3D object OBJ (3-dimensional object). The 3D object OBJ includes a polygon object POa for rendering the printing medium PM and a polygon object POb for rendering the printing layer.

[0061] Two polygon objects POa and POb are arranged parallel to each other. The normal vector Np of polygon object POa faces the surface of 3D object OBJ. 3D object OBJ is illuminated by light source LS. In FIGS. 11 and 12, the line of sight of camera CM is indicated by a dashed arrow. In rendering processing, 3D object OBJ is treated as a transparent object. For convenience, the distance between the two polygon objects POa and POb is depicted as large in FIGS. 11 and 12. However, in reality, the distance between polygon objects POa and POb in virtual space is very short so that Z-fighting does not occur. Furthermore, in virtual space, the thickness of polygon object POa representing printing medium PM reflects the thickness of printing medium PM, while the thickness of polygon object POb representing the printing layer is almost zero.

[0062] 11 and 12 depict, as coordinate systems used in the rendering process, a local coordinate system Σm (also called a model coordinate system), which is a three-dimensional Cartesian coordinate system of the 3D object OBJ, a world coordinate system Σg (also called a global coordinate system), which is a three-dimensional Cartesian coordinate system of the virtual space, and a view coordinate system Σc (also called a camera coordinate system), which is a three-dimensional Cartesian coordinate system of the camera CM placed in the virtual space. Other coordinate systems, such as a screen coordinate system, which is the coordinate system of the screen onto which the scene viewed from the camera CM is projected, are also used in the rendering process, but are omitted from FIGS. 11 and 12.

[0063] As shown in FIG. 11, when the line of sight of the camera CM is directed toward the front side of the 3D object OBJ, a front side view of the front side of the 3D object OBJ observed through the camera CM is generated as a rendering image.

[0064] As shown in FIG. 12, when the back side of the 3D object OBJ faces the line of sight of the camera CM, a back side view of the back side of the 3D object OBJ observed through the camera CM is generated as a rendering image.

[0065] The polygon objects POa and POb may each be composed of a single polygon. Alternatively, the polygon objects POa and POb may each be composed of multiple small polygons. If the polygon objects are composed of multiple polygons, it is possible to easily generate rendering images of not only flat printed matter but also curved printed matter.

[0066] In response to a user's instruction, the image processing device 100 of this embodiment can change the posture of a 3D object representing a printed matter in a virtual space and display a preview image representing the changed printed matter on the display device 300. As described above, the display device 300 has a function as a pointing device. The user can instruct the display of the preview image to be switched by performing a touch operation on the image displayed on the display device 300.

[0067] FIG. 13 is a flowchart showing a preview image display switching process. The process shown in FIG. 13 is executed by the processor 103 functioning as the rendering unit 160 and the update receiving unit 165. It is assumed that the initial preview image is displayed in the display area FV2 of the user interface UI when the process shown in FIG. 13 starts. In step S501, it is determined whether a touch operation instructing display switching has been performed. A touch operation instructing display switching refers to a tap operation or a double-tap operation on the preview image displayed in the display area FV2 of the user interface UI shown in FIG. 6. For convenience, the following description will be given assuming that the touch operation is only a tap operation on the display area FV2 or a double-tap operation on the display area FV2. If a touch operation has been performed (step S501; YES), the process of step S502 is executed. In step S502, it is determined whether the touch operation is a tap. If the touch operation is a tap operation on the preview image (step S502; YES), the process of step S503 is executed. In step S502, if the touch operation is an operation of double-tapping the preview image (step S502; NO), the process of step S504 is executed. Tapping the preview image is an operation instructing to display the side opposite to the currently displayed side. Double-tapping the preview image is an operation instructing to display the default side. The default side is, for example, the front side.

[0068] In step S503, it is determined that the side opposite to the currently displayed side is to be displayed. If the currently displayed side is the front side, it is determined that display switching is performed to display the back side. If the currently displayed side is the back side, it is determined that display switching is performed to display the front side.

[0069] In step S504, it is determined that the default surface is to be displayed.

[0070] In step S505, it is determined whether display switching is necessary. If it is determined in step S503 that the opposite side to the currently displayed side should be displayed, it is determined that display switching is necessary. If it is determined in step S504 that the default side should be displayed and the currently displayed side is the back side, it is determined that display switching should be performed to display the front side. If it is determined in step S504 that the default side should be displayed and the currently displayed side is the front side, it is determined that display switching should not be performed.

[0071] If the display needs to be switched (step S505; YES), the process proceeds to step S506. If the display needs not be switched (step S505; NO), the process proceeds to step S508.

[0072] In step S506, the rendering process is executed again, and a new rendering image is generated. If the displayed surface is the front surface and display switching is required, the positions of the 3D objects are changed so that the back surface is displayed. As a result, a rendering image is generated in which the back surface of the printed material faces forward. If the displayed surface is the back surface and display switching is required, the positions of the 3D objects are changed so that the front surface is displayed. As a result, a rendering image is generated in which the front surface of the printed material faces forward.

[0073] FIG. 14 is an explanatory diagram showing how the image processing device 100 redisplays a rendering image in response to a touch operation. In step S507, the newly generated rendering image is displayed as a preview image in the display area FV2 of the user interface UI. Furthermore, display surface information is displayed in the display area FV3. If the new display surface is the front surface, the display surface information "Front" is displayed in the display area FV3. If the new display surface is the back surface, the display surface information "Back" is displayed in the display area FV3. For example, when the preview image displayed in the display area FV2 shown in FIG. 6 is tapped, the display surface is switched as shown in FIG. 14. This allows the user to easily recognize which side of the virtual three-dimensional object representing the printed material is being displayed. The display surface information is also referred to as "display information." The display information indicates how the 3D object represented by the currently displayed preview image appears.

[0074] In step S508, it is determined whether or not to end the process. For example, if the print button BTP is pressed on the user interface UI, it is determined that the process should be ended. If it is determined that the process should be ended (step S508; YES), the process shown in FIG. 13 is ended. If it is determined that the process should be continued (step S508; NO), the process of step S501 is executed again. The processes of steps S501 to S508 are repeatedly executed until the print button BTP is pressed.

[0075] FIG. 15 is an explanatory diagram of the effects of this embodiment. The upper left frame shows a printed matter PT3 in which the printing medium PM and the color layer CL1 are overlaid by front printing. The lower left frame shows preview images of the front and back sides of the printed matter PT3. The upper right frame shows a printed matter PT4 in which the printing medium PM and the color layer CL2 are overlaid by back printing. The lower right frame shows preview images of the front and back sides of the printed matter PT4. As shown in FIG. 15, the front image SG1 representing the front side of the printed matter PT3 in the front-side printing case and the back image RG2 representing the back side of the printed matter PT4 in the back-side printing case appear similar. Furthermore, the back image RG1 representing the back side of the printed matter PT3 in the front-side printing case and the front image SG2 representing the front side of the printed matter PT4 in the back-side printing case appear similar, even though they are both observed through the transparent printing medium PM. For this reason, as users repeatedly switch between the front preview screen and the back preview screen, it is expected that it will become difficult for them to determine whether the currently displayed side is the front or back side using only the virtual 3D display of the printed matter.

[0076] However, in this embodiment, display surface information indicating whether the appearance of the 3D object representing the printed matter represents the front or back side of the printed matter is displayed in the display area FV3 together with the preview image. Therefore, the user can easily understand whether the currently displayed surface is the front or back side. Furthermore, the user can easily change the appearance of the virtual 3D object representing the printed matter with a simple operation. Therefore, user operability can be improved.

[0077] B. Other Embodiments: B1. Alternative Embodiment 1: In the above embodiment, the text information indicating the front and back sides of the printed matter is displayed. Alternatively, the information indicating the front and back sides of the printed matter may be displayed using icons. Fig. 16 is an explanatory diagram showing an example of displaying display information according to another embodiment 1.

[0078] The top row of Figure 16 shows an example of a user interface UI displaying a preview image of the front side of a printed material. An icon SM1 is displayed at the top of the preview image, indicating that the front side is being displayed. The bottom row of Figure 16 shows an example of a user interface UI displaying a preview image of the back side of a printed material. Assume that there is a virtual arrow that runs perpendicularly through a plane parallel to the front and back sides of the printed material. This arrow points from the back side of the printed material to the front side. In the top row of Figure 16, icon SM1 represents the shape of the arrow when viewed from the front, indicating the direction of the virtual arrow. In the bottom row of Figure 16, icon SM2 represents the shape of the arrow when viewed from the rear, indicating the direction of the virtual arrow. Icon SM1 is also referred to as the "icon for the front side." Icon SM2 is also referred to as the "icon for the back side." Display information indicating the appearance of a virtual three-dimensional object representing the printed material is displayed, allowing the user to easily understand the appearance of the currently displayed three-dimensional object.

[0079] B2. Alternative Embodiment 2: In the above embodiment, an example has been described in which either the front or back side of a printed matter is displayed as a preview image in the user interface UI. Alternatively, the user may be able to freely change the orientation of a virtual 3D object representing the printed matter in the display area FV2 of the user interface UI. This improves user operability.

[0080] Fig. 17 is a flowchart showing an example of a preview image display switching process according to another embodiment 2. It is assumed that the initial preview image is displayed in the display area FV2 of the user interface UI when the process shown in Fig. 17 starts. In step S601, it is determined whether or not a touch operation has been performed on the preview image displayed in the display area FV2 of the user interface UI. If a touch operation has been performed (step S601; YES), the process of step S602 is executed. In step S602, it is determined whether or not to end the process.

[0081] For example, if the touch operation detected in step S601 is an operation of pressing the print button BTP on the user interface UI, it is determined that the process is to be terminated. If it is determined that the process is to be terminated (step S602; YES), the process shown in Fig. 17 is terminated. If it is determined that the process is not to be terminated (step S602; NO), the process of step S603 is executed.

[0082] FIG. 18 is an explanatory diagram showing an example of a display mode of a preview image according to Alternative Embodiment 2. As shown in FIG. 18, an arrow SM3 is displayed in the display area FV2 together with the preview image of the printed matter. The arrow SM3 is an arrow that perpendicularly penetrates a plane parallel to the front and back surfaces of the printed matter, and is a 3D object that represents an arrow pointing from the back surface to the front surface of the printed matter. The arrow SM3 indicates the direction in which the front surface of the 3D object representing the printing medium PM faces. This allows the user to easily understand the orientation of the printed matter. The arrow SM3 is also called an "icon." Furthermore, display surface information representing the display surface of the printed matter is displayed in the display area FV3.

[0083] 17, the attitude of the virtual 3D object representing the printed matter is changed in accordance with the touch operation detected in step S601. Furthermore, the attitude of the 3D object representing the arrow SM3 is changed to match the attitude of the virtual 3D object representing the printed matter.

[0084] In step S604, it is determined whether the front side of the printed material after the orientation change is facing the line of sight of the virtual camera. If the front side of the printed material after the orientation change is facing the line of sight of the virtual camera (step S604; YES), the display side is determined to be the "front side" in step S605. If the front side of the printed material after the orientation change is not facing the line of sight of the virtual camera, that is, if the back side of the printed material after the orientation change is facing the line of sight of the virtual camera (step S604; NO), the display side is determined to be the "back side" in step S606.

[0085] In step S607, the display of the preview image is updated. Specifically, a preview image representing the virtual 3D object representing the printed matter whose orientation has been changed in step S603 is displayed in display area FV2. Furthermore, display surface information representing the display surface determined in step S605 or step S606 is displayed in display area FV3. Thereafter, the processing of step S601 is executed again.

[0086] The user may also instruct the display or non-display of the arrow SM3 by a predetermined touch operation. The predetermined touch operation is to tap the area around the arrow SM3 or the virtual 3D object representing the printed material. This operation instruction is also referred to as a “switching instruction.” When the arrow SM3 is displayed, upon receiving this operation instruction, the rendering unit 160 hides the arrow SM3. When the arrow SM3 is not displayed, the user may instruct the display of the arrow SM3 by tapping the area around the virtual 3D object representing the printed material. When the arrow SM3 is not displayed, upon receiving this operation instruction, the rendering unit 160 displays the arrow SM3. Since display information indicating the appearance of the virtual 3D object representing the printed material is displayed, the user can easily understand the appearance of the currently displayed 3D object. Since the user can appropriately select whether to display or non-display the arrow SM3 representing the attitude of the virtual printed material, usability is improved. Furthermore, since the display or non-display of the arrow SM3 can be switched by a touch operation, user operability is improved.

[0087] Furthermore, it is not necessary to display text information indicating the front or back side as shown in Fig. 18. In this case, if the orientation in the virtual space of the 3D object representing the print medium PM indicates that the line of sight of the virtual camera is perpendicular to the surface of the 3D object, an icon such as that shown in Fig. 16 may be displayed. When the front side of the printed matter is displayed as a preview image, an icon SM1 such as that shown in the upper part of Fig. 16 may be displayed. When the front side of the printed matter is displayed as a preview image, an icon SM2 such as that shown in the lower part of Fig. 16 may be displayed.

[0088] Alternatively, if the orientation of the 3D object representing the print medium PM in the virtual space indicates that the line of sight of the virtual camera is perpendicular to the surface of the 3D object, icon SM1 or SM2 may be hidden without receiving an instruction to hide icon SM1 or SM2. If the orientation of the 3D object representing the print medium PM is changed by a user operation so that the line of sight of the virtual camera is no longer perpendicular to the surface of the 3D object, arrow SM3 may be displayed again.

[0089] B3. Alternative Embodiment 3: In the above embodiment, the preview image is displayed in a manner that changes the posture of the 3D object representing the printed matter in the virtual space. The preview image may also be displayed in a manner that changes the viewpoint position and line of sight of a virtual camera relative to the 3D object representing the printed matter in the virtual space.

[0090] FIG. 19 is an explanatory diagram showing the positional relationship between a virtual object representing a printed matter and a camera placed in virtual space. The camera CMV placed in virtual space is always pointed toward the center of the object representing the printed matter PT5. As the camera CMV moves around the object representing the printed matter PT5, the viewpoint position and line of sight of the camera CMV change. The preview image is displayed in a manner that changes the viewpoint position and line of sight of the camera CMV. Thus, the user can view the 3D object representing the printed matter in virtual space from the viewpoint position and line of sight of the camera CMV moving around the object representing the printed matter PT5.

[0091] Furthermore, to represent the viewpoint position and line of sight of the camera CMV placed in the virtual space, an icon resembling the shape of the virtual camera CMV may be displayed in the display area FV2 of the user interface UI together with the object representing the printed material PT5. The icon resembling the shape of the virtual camera CMV represents the viewpoint position and line of sight of the camera CMV placed in the virtual space. Furthermore, an icon resembling the shape of a human eye may be displayed in the display area FV2 of the user interface UI together with the object representing the printed material PT5. The icon resembling the shape of a human eye represents the viewpoint position and line of sight of the camera CMV placed in the virtual space. Display information indicating the appearance of a virtual three-dimensional object representing the printed material is displayed, allowing the user to easily understand the appearance of the currently displayed three-dimensional object. As in the second embodiment, the user may be able to select whether to display or hide the icon resembling the shape of the virtual camera CMV or the icon resembling the shape of a human eye by a predetermined touch operation. The user can appropriately select whether to display or hide the icon representing the viewpoint position and line of sight of the virtual camera, thereby improving usability.

[0092] Furthermore, if the orientation of the 3D object representing the print medium PM in the virtual space indicates that the line of sight of the virtual camera is perpendicular to the surface of the 3D object, the icon may be hidden without receiving an instruction to hide the icon. If the orientation of the 3D object representing the print medium PM is changed by a user operation so that the line of sight of the virtual camera is no longer perpendicular to the surface of the 3D object, the icon may be displayed again.

[0093] B4. Alternative Embodiment 4: Fig. 20 is an explanatory diagram of a user interface UI according to another fourth embodiment. When a user can freely change the posture of a virtual 3D object representing a printed material in the display area FV2 of the user interface UI, the following problem may arise. In the example shown in Fig. 20, the image represented by the input image data IMi is symmetrical both left and right and top and bottom. In the case of such an image, the user may find it difficult to grasp the top, bottom, left, and right positions of the image represented by the input image data IMi in the currently displayed preview image.

[0094] For this reason, in the illustrated example, position information FP representing the top, bottom, left, and right sides of the surface of the input image data IMi is displayed together with the preview image, allowing the user to easily grasp the top, bottom, left, and right positions of the image represented by the input image data IMi in the currently displayed preview image.

[0095] C. Other forms: The present disclosure is not limited to the above-described embodiments and can be realized in various configurations without departing from the spirit thereof. For example, the technical features in the embodiments corresponding to the technical features in each aspect described in the Summary of the Invention section can be appropriately replaced or combined to solve some or all of the above-described problems or achieve some or all of the above-described effects. Furthermore, if a technical feature is not described as essential in this specification, it can be deleted as appropriate.

[0096] (1) According to a first aspect of the present disclosure, there is provided an image processing method, including: (a) receiving one or more print layers to be stacked on a print medium by printing on the print medium and a stacking order of the print media; (b) displaying, on a display device, a preview image representing a virtual three-dimensional object of a printed matter formed by stacking the one or more print layers and the print medium in the stacking order, the preview image corresponding to how the object will appear in a three-dimensional virtual space; (c) receiving a change instruction to change the appearance of the three-dimensional object; (d) changing, in accordance with the change instruction, at least one of the posture of the three-dimensional object in the virtual space and the viewpoint position and line of sight of a virtual camera relative to the three-dimensional object in the virtual space so as to change the appearance of the three-dimensional object, and displaying, on the display device, the preview image representing the changed three-dimensional object; and (e) displaying, on the display device, display information indicating how the three-dimensional object will appear in the currently displayed preview image. In the above embodiment, the appearance of the virtual three-dimensional object representing the printed matter can be easily changed. Furthermore, since display information indicating the appearance of the virtual three-dimensional object representing the printed matter is displayed, the user can easily understand the appearance of the currently displayed three-dimensional object. Therefore, user operability can be improved. (2) In the image processing method of the above aspect, in the step (e), character information indicating whether the front or back surface of the three-dimensional object is being displayed may be displayed as the display information. According to the above aspect, the user can easily recognize which side of the virtual three-dimensional object representing the printed matter is being displayed. (3) In the image processing method of the above aspect, in the step (e), an icon indicating the direction in which the surface of the three-dimensional object faces may be displayed as the display information in the image displayed together with the three-dimensional object. (4) In the image processing method of the above aspect, in the step (e), an icon indicating a viewpoint position and a line of sight direction of the virtual camera relative to the three-dimensional object may be displayed as the display information. (5) The image processing method of the above aspect may further include: (f) a step of receiving a switching instruction to switch between displaying and hiding the icon; and (g) a step of displaying or hiding the icon in accordance with the switching instruction. According to the above aspect, the user can select whether to display or not display the icon as display information, thereby improving the operability for the user. (6) In the image processing method of the above aspect, (h) when the front or back surface of the three-dimensional object faces forward, or when the line of sight of the virtual camera is perpendicular to the front or back surface of the three-dimensional object, the image processing method may further include a step of hiding the icon without accepting an instruction to hide the icon. (7) The image processing method of the above aspect may further include the step of: (i) displaying an icon for the front side as the display information when the front or back side of the three-dimensional object faces forward, or when the line of sight of the virtual camera is perpendicular to the front or back side of the three-dimensional object, and when the front side of the three-dimensional object is displayed, displaying an icon for the back side as the display information when the back side of the three-dimensional object is displayed. (8) According to a second aspect of the present disclosure, there is provided an image processing device including: a print setting receiving unit that receives one or more print layers to be stacked on a print medium by printing on the print medium and a stacking order of the print media; a display processing unit that displays, on a display device, a preview image representing a virtual three-dimensional object of a printed matter formed by stacking the one or more print layers and the print medium in the stacking order, the preview image corresponding to how the object will appear in a three-dimensional virtual space; and a change receiving unit that receives a change instruction to change the appearance of the three-dimensional object, wherein, when the change receiving unit receives the change instruction, the display processing unit changes at least one of an orientation of the three-dimensional object in the virtual space and a viewpoint position and a line of sight direction of a virtual camera relative to the three-dimensional object in the virtual space so that the appearance of the three-dimensional object is changed in accordance with the change instruction, and displays, on the display device, a preview image representing the three-dimensional object after the change and display information indicating how the three-dimensional object will appear as represented by the preview image after the change. In the above embodiment, the appearance of the virtual three-dimensional object representing the printed matter can be easily changed. Furthermore, since display information indicating the appearance of the virtual three-dimensional object representing the printed matter is displayed, the user can easily understand the appearance of the currently displayed three-dimensional object. Therefore, user operability can be improved. (9) According to a third aspect of the present disclosure, a printing system is provided. The printing system includes an image processing device, a printing device, and a display device. The image processing device includes a print setting receiving unit that receives one or more printing layers to be stacked on a printing medium by printing on the printing medium and a stacking order of the printing media; a display processing unit that displays, on the display device, a preview image representing a virtual three-dimensional object of a printed matter in which the one or more printing layers and the printing medium are stacked in the stacking order, the preview image corresponding to how the object will appear in a three-dimensional virtual space; and a change receiving unit that receives a change instruction to change the appearance of the three-dimensional object. When the change receiving unit receives the change instruction, the display processing unit changes at least one of the orientation of the three-dimensional object in the virtual space and the viewpoint position and line of sight of a virtual camera relative to the three-dimensional object in the virtual space so that the appearance of the three-dimensional object is changed in accordance with the change instruction, and displays, on the display device, a preview image representing the three-dimensional object after the change and display information indicating how the three-dimensional object will appear in the preview image after the change. In the above embodiment, the appearance of the virtual three-dimensional object representing the printed matter can be easily changed. Furthermore, since display information indicating the appearance of the virtual three-dimensional object representing the printed matter is displayed, the user can easily understand the appearance of the currently displayed three-dimensional object. Therefore, user operability can be improved. (10) According to a fourth aspect of the present disclosure, there is provided an image processing program that causes a computer to implement the following functions: (a) accepting one or more printing layers to be laminated on a printing medium by printing on the printing medium and a layering order of the printing media; (b) displaying, on a display device, a preview image representing a virtual three-dimensional object of a printed matter in which the one or more printing layers and the printing medium are laminated in the layering order, the preview image corresponding to how the object will appear in a three-dimensional virtual space; (c) accepting a change instruction to change the appearance of the three-dimensional object; (d) changing, in accordance with the change instruction, at least one of the orientation of the three-dimensional object in the virtual space and the viewpoint position and line of sight of a virtual camera relative to the three-dimensional object in the virtual space so as to change the appearance of the three-dimensional object, and displaying, on the display device, the preview image representing the changed three-dimensional object; and (e) displaying, on the display device, display information indicating how the three-dimensional object will appear in the currently displayed preview image. In the above embodiment, the appearance of the virtual three-dimensional object representing the printed matter can be easily changed. Furthermore, since display information indicating the appearance of the virtual three-dimensional object representing the printed matter is displayed, the user can easily understand the appearance of the currently displayed three-dimensional object. Therefore, user operability can be improved. [Explanation of symbols]

[0097] 10...printing system, 100...image processing device, 101...memory, 102...input / output interface, 103...processor, 104...internal bus, 110...image data acquisition unit, 120...profile acquisition unit, 130...printing condition acquisition unit, 140...parameter acquisition unit, 150...preprocessing unit, 151...color management system, 153...medium color calculation unit, 155...observation image generation unit, 160...rendering unit, 170... Print data generation unit, 171...setting unit, 173...plate separation unit, 175...halftone processing unit, 200...input device, 300...display device, 400...printing device, BT1...button, BT2...button, BT4...button, BT5...button, BTP...print button, CC1...first color conversion, CC2...second color conversion, CC3...third color conversion, CC4...fourth color conversion, CL...color layer, CM...camera, CMI...camera information, CMV...camera, CPF...common Color space profile, CTb...color conversion table for print media, FV1-FV3...display area, GS...geometry shader, IMd...device color image data, IMi...input image data, IMm...image data for rendering, IPF...input profile, LS...light source, MPF...media profile, Np...normal vector, OBJ...3D object, PG...program, PM...print media, POa...polygon object, POb...polygon object, PPL...pixel pipeline, PS...pixel shader, PST...post-processing unit, PT1-PT5...printed material, RBE...render backend, RG,RG1,RG2...backside image, RRZ...rasterizer, SG,SG1,SG2...front side image, SM1,SM2...icon, SM3...arrow, UI...user interface, VPL...vertex pipeline, VS...vertex shader

Claims

1. 1. An image processing method, comprising: (a) receiving one or more printing layers to be printed on a print medium and a stacking order of the print medium; (b) displaying on a display device a preview image representing a virtual three-dimensional object of a printed matter in which the one or more printing layers and the printing medium are superimposed in the stacking order, the preview image corresponding to how the image will appear in a three-dimensional virtual space; (c) receiving a modification instruction to modify the appearance of the three-dimensional object; (d) changing at least one of the posture of the three-dimensional object in the virtual space and the viewpoint position and line of sight of a virtual camera relative to the three-dimensional object in the virtual space in response to the change instruction so that the appearance of the three-dimensional object is changed, and displaying the preview image representing the three-dimensional object after the change on the display device; (e) displaying, on the display device, display information indicating how the three-dimensional object represented by the currently displayed preview image will appear, together with the preview image; An image processing method comprising:

2. 2. The image processing method according to claim 1, In the step (e), character information indicating whether the front surface or the back surface of the three-dimensional object is being displayed is displayed as the display information. Image processing methods.

3. 2. The image processing method according to claim 1, In the step (e), an icon indicating a direction in which a surface of the three-dimensional object faces is displayed as the display information, the icon being an image to be displayed together with the three-dimensional object. Image processing methods.

4. 2. The image processing method according to claim 1, In the step (e), an icon indicating a viewpoint position and a line of sight direction of the virtual camera with respect to the three-dimensional object is displayed as the display information. Image processing methods.

5. 5. The image processing method according to claim 3, further comprising: (f) receiving a switching instruction to switch between displaying and hiding the icon; (g) displaying the icon or hiding the icon in response to the switching instruction; further comprising: Image processing methods.

6. 5. The image processing method according to claim 3, further comprising: (h) hiding the icon without accepting an instruction to hide the icon when the front or back surface of the three-dimensional object faces forward or when the line of sight of the virtual camera is perpendicular to the front or back surface of the three-dimensional object; further comprising: Image processing methods.

7. 5. The image processing method according to claim 3, further comprising: (i) when the front or back surface of the three-dimensional object faces forward, or when the line of sight direction of the virtual camera is perpendicular to the front or back surface of the three-dimensional object, When the surface of the three-dimensional object is displayed, an icon for the surface is displayed as the display information; a step of displaying an icon for the back side as the display information when the back side of the three-dimensional object is displayed; further comprising: Image processing methods.

8. An image processing device, a print setting receiving unit that receives one or more print layers to be laminated on the print medium by printing on the print medium and a lamination order of the print medium; a display processing unit that displays, on a display device, a preview image representing a virtual three-dimensional object of a printed matter in which the one or more printing layers and the printing medium are superimposed in the stacking order, the preview image corresponding to how the object will appear in a three-dimensional virtual space; and a change receiving unit that receives a change instruction to change the appearance of the three-dimensional object; Equipped with The display processing unit When the change receiving unit receives the change instruction, at least one of an attitude of the three-dimensional object in the virtual space and a viewpoint position and a line of sight direction of a virtual camera relative to the three-dimensional object in the virtual space is changed so that an appearance of the three-dimensional object is changed in accordance with the change instruction; a preview image representing the three-dimensional object after the change and display information indicating how the three-dimensional object represented by the preview image after the change will appear are displayed on the display device; Image processing device.

9. 1. A printing system comprising: An image processing device, a printing device, and a display device, Equipped with The image processing device includes: a print setting receiving unit that receives one or more print layers to be laminated on the print medium by printing on the print medium and a lamination order of the print medium; a display processing unit that displays, on the display device, a preview image representing a virtual three-dimensional object of a printed matter in which the one or more printing layers and the printing medium are superimposed in the stacking order, the preview image corresponding to how the object will appear in a three-dimensional virtual space; and a change receiving unit that receives a change instruction to change the appearance of the three-dimensional object; Equipped with The display processing unit When the change receiving unit receives the change instruction, at least one of an attitude of the three-dimensional object in the virtual space and a viewpoint position and a line of sight direction of a virtual camera relative to the three-dimensional object in the virtual space is changed so that an appearance of the three-dimensional object is changed in accordance with the change instruction; a preview image representing the three-dimensional object after the change and display information indicating how the three-dimensional object represented by the preview image after the change will appear are displayed on the display device; Printing system.

10. An image processing program, (a) receiving one or more printing layers to be printed on a print medium and a stacking order of the print medium; (b) a function of displaying on a display device a preview image representing a virtual three-dimensional object of a printed matter in which the one or more printing layers and the printing medium are superimposed in the stacking order, the preview image corresponding to how the image will appear in a three-dimensional virtual space; and (c) a function of receiving a change instruction to change the appearance of the three-dimensional object; (d) a function of changing at least one of the posture of the three-dimensional object in the virtual space and the viewpoint position and line of sight direction of a virtual camera relative to the three-dimensional object in the virtual space in response to the change instruction so that the appearance of the three-dimensional object is changed, and displaying the preview image representing the three-dimensional object after the change on the display device; (e) a function of displaying, on the display device, display information indicating how the three-dimensional object represented by the currently displayed preview image appears together with the preview image; An image processing program that enables a computer to achieve this.

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