Image processing method and image processing apparatus

Abstract

To reduce the influence on an output image caused by a difference in a situation when a medium is read in print simulation.SOLUTION: A processor 51 corrects medium image data according to the ratio between maximum medium brightness that is the maximum brightness in the medium image data and maximum output brightness that is the maximum brightness in an output profile set in advance corresponding to an image output device, to generate corrected medium image data (S105). The processor 51 combines the corrected medium image data and printing target image data to generate composite image data (S204). The processor 51 converts the composite image data into output image data on the basis of the output profile, and outputs the output image data to the image output device (S206).SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to an image processing method and an image processing apparatus for generating an output image by synthesizing a media image and a print target image.

Background Art

[0002] Before an image is printed on a medium such as cloth, print simulation may be performed (see, for example, Patent Document 1).

[0003] In the print simulation, an output image obtained by synthesizing a media image and a print target image is output by a display device or an image forming device. The print target image is an image to be printed on the medium.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, when the print simulation is performed, data of the media image is obtained by reading the media with an image reading device.

[0006] The brightness of the media image varies depending on the situation when the media is read by the image reading device.

[0007] For example, when the media is read with the document cover of the image reading device open, data of the relatively bright media image is obtained. On the other hand, when the media is read with the document cover closed, data of the relatively dark media image is obtained.

[0008] In the print simulation, the impression of the output image changes depending on the brightness of the media image. However, it is desirable that the brightness of the media image does not affect the output image.

[0009] An object of the present invention is to provide an image processing method and an image processing apparatus capable of reducing the influence of differences in situations when media is read during print simulation on an output image.

Means for Solving the Problems

[0010] An image processing method according to one aspect of the present invention includes a processor acquiring media image data representing an image of media before a print target image is formed. Further, the image processing method includes the processor generating corrected media image data by correcting the media image data according to a ratio between a maximum media brightness that is the maximum brightness in the media image data and a maximum output brightness that is the maximum brightness in a preset output profile corresponding to an image output device. Further, the image processing method includes the processor generating composite image data by synthesizing the corrected media image data and print target image data representing the print target image. Further, the image processing method includes the processor converting the composite image data into output image data based on the output profile and outputting the output image data to the image output device.

[0011] An image processing apparatus according to another aspect of the present invention includes the processor that realizes the image processing method.

Effects of the Invention

[0012] According to the present invention, it becomes possible to provide an image processing method and an image processing apparatus capable of reducing the influence of differences in situations when media is read during print simulation on an output image.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

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Figure 5

Embodiments for Carrying Out the Invention

[0014] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the following embodiments are an example of embodying the present invention and do not limit the technical scope of the present invention.

[0015] [Configuration of Image Processing Apparatus 10] The image processing apparatus 10 according to the embodiment includes an image reading apparatus 1 and an image forming apparatus 2. Further, the image processing apparatus 10 also includes a control device 5 and a user interface device 3.

[0016] For example, the image processing apparatus 10 is a copier, a facsimile apparatus, or a multifunction machine, etc.

[0017] The image reading apparatus 1 executes an image reading process for reading an image from a document 91. The image forming apparatus 2 executes a printing process for forming an image on a sheet-like medium 92 such as paper or cloth.

[0018] The image reading device 1 includes an optical scanning unit that scans light on the document 91, and an image sensor that receives the reflected light reflected from the document 91. The image sensor sequentially reads a plurality of line images from the document 91 and outputs a plurality of line image signals LS1 representing the plurality of line images to the control device 5.

[0019] The image forming device 2 executes the printing process by a predetermined method such as an electrophotographic method or an inkjet method. The image forming device 2 includes a sheet conveyance unit that conveys the medium 92, and a printing unit that forms an image on the medium 92.

[0020] The user interface device 3 includes an operation device 3a and a display device 3b. The operation device 3a is a device that receives human operations. For example, the operation device 3a includes operation buttons and a touch panel, etc. The display device 3b can display various images and information. For example, the display device 3b includes a display panel such as a liquid crystal panel.

[0021] The communication device 4 is a communication interface device that communicates with other devices such as the host device 7 through a network 70 such as a LAN (Local Area Network). The control device 5 performs all data transmission and reception with the other devices through the communication device 4.

[0022] The host device 7 can communicate with the image processing device 10. The host device 7 includes a communication device 71, a data processing device 72, a display device 73, and an operation device 74.

[0023] The data processing device 72 transmits and receives data to and from the image processing device 10 through the communication device 71. The data processing device 72 includes a processor such as a CPU and executes various data processes.

[0024] The display device 73 can display various images and information. For example, the display device 3b includes a display panel such as a liquid crystal panel. The operating device 74 is a device that accepts human operations. For example, the operating device 74 includes a keyboard, a mouse, or a touch panel, etc.

[0025] The data processing device 72 causes the display device 73 to display various images or information. Also, the data processing device 72 executes various data processes according to the information input through the operating device 74.

[0026] The control device 5 executes various operations, data processing, and control of various electrical devices provided in the image processing device 10.

[0027] As shown in FIG. 2, the control device 5 includes a CPU (Central Processing Unit) 51, a RAM (Random Access Memory) 52, a secondary storage device 53, a signal interface 54, and a digital conversion circuit 55, etc.

[0028] The CPU 51 executes various data processes and controls by executing a computer program. The CPU 51 is an example of a processor. It is also conceivable that another processor such as a DSP executes the data processing and control in place of the CPU 51.

[0029] The RAM 52 is a computer-readable volatile storage device. The RAM 52 stores temporarily the computer program executed by the CPU 51 and the data output and referenced by the CPU 51 during the execution of the computer program.

[0030] The secondary storage device 53 is a computer-readable non-volatile storage device. The secondary storage device 53 can store the computer program and various data. For example, one or both of an SSD (Solid State Drive) and a hard disk drive are adopted as the secondary storage device 53.

[0031] The digital conversion circuit 55 converts a plurality of line image signals LS1 output from the image reading device 1 into digital read image data DT1. The digital conversion circuit 55 includes an AFE (Analog Front End) that converts each analog line image signal LS1 into digital data. In the present embodiment, the read image data DT1 is RGB data.

[0032] The CPU 51 includes a plurality of processing modules realized by executing the computer program. The plurality of processing modules in the CPU 51 include a main control unit 5a, a job control unit 5b, an image processing unit 5c, and the like.

[0033] The main control unit 5a mainly monitors operations on the operation device 3a and data reception by the communication device 4. Further, when the main control unit 5a detects an operation on the operation device 3a or data reception, it controls the start of processing according to the detected content.

[0034] The job control unit 5b controls the image reading device 1 and the image forming device 2. The image processing unit 5c executes various image processes on the image data obtained through the digital conversion circuit 55 or the communication device 4. The image data obtained through the digital conversion circuit 55 is the read image data DT1 representing the image read from the document 91 by the image reading device 1.

[0035] Print simulation may be performed before the printing process on the medium 92 such as cloth.

[0036] In the print simulation, an output image in which the media image and the print target image are combined is displayed by the display device. For example, the output image is displayed by the display device 73 of the host device 7 or the display device 3b of the image processing device 10. The print target image is the image to be printed on the medium 92.

[0037] Incidentally, when the print simulation is performed, a medium 92 such as cloth is read by the image reading device 1, and data of the medium image is obtained.

[0038] The brightness of the medium image varies depending on the situation when the medium 92 is read by the image reading device 1.

[0039] For example, when the medium 92 is read with the document cover of the image reading device 1 open, data of the relatively bright medium image is obtained. On the other hand, when the medium is read with the document cover closed, data of the relatively dark medium image is obtained.

[0040] In the print simulation, the impression of the output image changes depending on the brightness of the medium image. However, it is desirable that the brightness of the medium image does not affect the output image.

[0041] In the image processing apparatus 10, the image processing unit 5c executes a print simulation process described later (see FIG. 3). The print simulation process includes a process for reducing the influence of differences in the situation when the medium 92 is read on the output image.

[0042] [Print Simulation Process] Hereinafter, an example of the procedure of the print simulation process will be described with reference to the flowchart shown in FIG. 3.

[0043] The main control unit 5a causes the image processing unit 5c to execute the print simulation process when the operation device 3a detects a predetermined simulation start operation.

[0044] The print simulation process is an example of a process for realizing an image processing method. The CPU 51 that executes the print simulation process is an example of a processor for realizing the image processing method.

[0045] In the following description, S101, S102, … represent identification codes of a plurality of steps in the print simulation process. In the print simulation process, first, the process of step S101 is executed.

[0046] <Step S101> In step S101, the image processing unit 5c acquires primary media image data. The primary media image data is image data of the media 92 obtained by the reading process of the media 92 by the image reading device 1.

[0047] For example, the print simulation process is executed when the media 92 is a cloth having unevenness on the surface. More specifically, it is conceivable that the media 92 is a white-based cloth.

[0048] In the present embodiment, the read image data DT1 obtained from the image reading device 1 through the digital conversion circuit 55 is the primary media image data. After executing the process of step S101, the image processing unit 5c executes the process of step S102.

[0049] <Step S102> In step S102, the image processing unit 5c acquires a read profile stored in the secondary storage device 53. The read profile is a profile preset corresponding to the image reading device 1.

[0050] In the present embodiment, the read profile is a color profile for converting RGB image data into Lab image data. The read profile represents the correspondence relationship between the data in the RGB color space of the image reading device 1 and the Lab color space.

[0051] After executing the process of step S102, the image processing unit 5c executes the process of step S103.

[0052] <Step S103> In step S103, the image processing unit 5c converts the primary media image data obtained in step S101 into secondary media image data based on the reading profile obtained in step S102.

[0053] In the present embodiment, the secondary media image data is Lab image data. The processing of steps S101 to S103 is an example of processing for acquiring media image data representing an image of the media 92 before the print target image is formed.

[0054] After executing the processing of step S103, the image processing unit 5c executes the processing of step S104.

[0055] <Step S104> In step S104, the image processing unit 5c acquires an output profile preset corresponding to the image output device.

[0056] In the present embodiment, the image output device is the display device 73 of the host device 7 or the display device 3b of the image processing device 10.

[0057] The output profile is a color profile for converting Lab image data into RGB image data. The output profile represents the correspondence relationship between the data in the Lab color space and the data in the RGB color space of the image output device.

[0058] After executing the processing of step S104, the image processing unit 5c executes the processing of step S105.

[0059] <Step S105> In step S105, the image processing unit 5c derives the ratio between the maximum media lightness, which is the maximum lightness in the secondary media image data, and the maximum output lightness, which is the maximum lightness in the output profile, as the lightness ratio.

[0060] Furthermore, in step S105, the image processing unit 5c generates corrected media image data by correcting the secondary media image data according to the brightness ratio.

[0061] When the process of step S105 is executed, if the brightness of the entire secondary media image data is too high or too low, the brightness of the entire secondary media image data is corrected according to the brightness of the output profile.

[0062] In step S105, the secondary media image data is processed as the media image data representing the media 92 before the image is formed.

[0063] After executing the process of step S105, the image processing unit 5c executes the process of step S106.

[0064] <Step S106> In step S106, the image processing unit 5c executes a shadow enhancement process on the corrected media image data. The shadow enhancement process is a process of enhancing an image with a low brightness that is lower than a predetermined brightness.

[0065] When the process of step S106 is executed, an image representing the unevenness of the surface of the media 92 such as cloth is reflected in the corrected media image data.

[0066] After executing the process of step S106, the image processing unit 5c executes the process of step S107.

[0067] <Step S107> In step S107, the image processing unit 5c executes a composite output process based on the corrected media image data and the print target image data.

[0068] After executing the process of step S107, the image processing unit 5c ends the print simulation process.

[0069] [Composite Output Process] Next, an example of the procedure of the composite output process will be described with reference to the flowchart shown in FIG. 4.

[0070] In the following description, S201, S202, … represent identification codes of a plurality of steps in the composite output process. In the composite output process, first, the process of step S201 is executed.

[0071] <Step S201> In step S201, the image processing unit 5c acquires primary print image data representing an image formed on the medium 92.

[0072] For example, the image processing unit 5c acquires the primary print image data from the host device 7 through the communication device 4. Alternatively, the image processing unit 5c acquires the primary print image data stored in the secondary storage device 53 in advance.

[0073] After executing the process of step S201, the image processing unit 5c executes the process of step S202.

[0074] <Step S202> In step S202, the image processing unit 5c acquires an input profile preset corresponding to the device that generated the primary print image data.

[0075] For example, the image processing unit 5c acquires the input profile together with the primary print image data from the host device 7 or the secondary storage device 53.

[0076] In the present embodiment, the input profile is a color profile for converting RGB image data or CMYK image data into Lab image data. The input profile represents the correspondence relationship between the data of the color space of the device that generated the primary print image data and the Lab color space.

[0077] After executing the process of step S202, the image processing unit 5c executes the process of step S203.

[0078] <Step S203> In step S203, the image processing unit 5c converts the primary print target image data obtained in step S201 into secondary print target image data based on the input profile obtained in step S202.

[0079] In the present embodiment, the secondary print target image data is Lab image data. After executing the process of step S203, the image processing unit 5c executes the process of step S204.

[0080] <Step S204> In step S204, the image processing unit 5c generates composite image data by synthesizing the corrected media image data subjected to the shadow enhancement process and the secondary print target image data.

[0081] The composite image data is image data that simulates a printed matter obtained by the printing process on the medium 92 based on the print target image data.

[0082] Here, a region corresponding to a white or transparent pixel in the secondary print target image data is referred to as a specific region.

[0083] In step S204, the image processing unit 5c executes a first data setting process and a second data setting process.

[0084] The first data setting process is a process of setting, for the specific region, the pixel data of the specific region in the corrected media image data as the pixel data of the specific region after synthesis.

[0085] The second data setting process is a process of setting, for a region other than the specific region, data obtained by synthesizing the pixel data of the region other than the specific region in the corrected media image data and the pixel data of the region other than the specific region in the print target image data as the pixel data of the region other than the specific region after synthesis.

[0086] In step S204, the secondary print target image data is processed as print target image data representing an image formed on the medium 92.

[0087] After executing the process of step S204, the image processing unit 5c executes the process of step S205.

[0088] <Step S205> In step S205, the image processing unit 5c converts the composite image data obtained in step S204 into output image data based on the output profile.

[0089] After executing the process of step S205, the image processing unit 5c executes the process of step S206.

[0090] <Step S206> In step S206, the image processing unit 5c outputs the output image data to the image output device.

[0091] For example, the image processing unit 5c outputs the output image data to the display device 73 of the host device 7 through the communication device 4. Alternatively, the image processing unit 5c outputs the output image data to the display device 3b.

[0092] By executing the process of step S206, an image simulating a printed matter obtained by the printing process on the medium 92 based on the print target image data is displayed on the display device 73 or the display device 3b.

[0093] After executing the process of step S206, the image processing unit 5c ends the composite output process.

[0094] By executing the print simulation shown in FIGS. 3 and 4, the influence of the difference in the situation when the medium 92 is read by the image reading device 1 on the output image is reduced.

[0095] [Application Example] Next, an application example of the print simulation process will be described while referring to the flowchart shown in FIG. 5.

[0096] Hereinafter, differences from the print simulation process shown in FIG. 3 in this application example will be described.

[0097] The print simulation process in this application example has a procedure in which step S104a and step S104b are added to the print simulation process shown in FIG. 3.

[0098] In this application example, after the image processing unit 5c acquires the output profile in step S104, it executes the process of step S104a.

[0099] [Step S104a] In step S104a, the image processing unit 5c derives a brightness comparison value CV1. The brightness comparison value CV1 represents the comparison result between the highest media brightness and the highest output brightness.

[0100] For example, the brightness comparison value CV1 is the difference between the highest media brightness and the highest output brightness. Also, the brightness comparison value CV1 may be the ratio of the highest media brightness to the highest output brightness.

[0101] After the image processing unit 5c executes the process of step S104a, it executes the process of step S104b.

[0102] [Step S104b] In step S104b, the image processing unit 5c selects the next process according to whether the brightness comparison value CV1 is within a predetermined allowable range or outside the allowable range.

[0103] When the brightness comparison value CV1 is outside the allowable range, the image processing unit 5c executes the process of step S105.

[0104] In step S105, the image processing unit 5c generates the corrected media image data by correcting the secondary media image data. As described above, the image processing unit 5c corrects the secondary media image data according to the brightness ratio which is the ratio of the highest media brightness to the highest output brightness (refer to step S105 in FIG. 3).

[0105] After executing the process of step S105, the image processing unit 5c executes the processes of step S106 and steps S201 to S206 (refer to steps S106 and S107 in FIG. 3).

[0106] On the other hand, when the brightness comparison value CV1 is within the allowable range, the image processing unit 5c executes the processes of step S106 and step S107 without executing the process of step S105.

[0107] When the process of step S105 is not executed, the image processing unit 5c executes the shadow enhancement process on the secondary media image data in step S106.

[0108] When the process of step S105 is not executed, the image processing unit 5c executes an application synthesis process in step S204 of the synthesis output process. The application synthesis process is a process of generating the synthesized image data by synthesizing the secondary media image data subjected to the shadow enhancement process and the secondary print target image data.

[0109] In this application example, when the brightness comparison value is within the allowable range, the image processing unit 5c executes the process of step S204 without executing the process of step S104. The synthesized image data generated in step S204 is an example of the first synthesized image data.

[0110] On the other hand, when the brightness comparison value is outside the allowable range, the image processing unit 5c generates the corrected media image data by executing the process of step S104. In this case, in step S204, the image processing unit 5c synthesizes the corrected media image data and the secondary print target image data. The synthesized image data generated by this synthesis is an example of the second synthesized image data.

[0111] Even when this application example is adopted, the same effects as those obtained when the print simulation process shown in FIG. 3 is adopted can be obtained.

Explanation of Reference Numerals

[0112] 1: Image reading device 2: Image forming device 3: User interface device 3a: Operating device 3b: Display device 4: Communication device 5: Control device 10: Image processing device 51: CPU (Processor)

Claims

1. The processor obtains media image data representing an image of the media before the print target image is formed; The processor generates corrected media image data by correcting the media image data according to a ratio between a maximum media brightness, which is the maximum brightness in the media image data, and a maximum output brightness, which is the maximum brightness in a preset output profile corresponding to the image output device; The processor generates composite image data by combining the corrected media image data and print target image data representing the print target image; The processor converts the composite image data into output image data based on the output profile, and outputs the output image data to the image output device. An image processing method comprising the steps.

2. The processor obtaining the media image data includes: The processor obtains primary media image data obtained by the media being read by an image reading device; The processor converts the primary media image data into secondary media image data based on a preset reading profile corresponding to the image reading device, The processor processes the secondary media image data as the media image data. The image processing method according to claim 1.

3. The processor includes converting primary print target image data representing the print target image into secondary print target image data based on a preset input profile, The processor processes the secondary print target image data as the print target image data. The image processing method according to claim 1 or claim 2.

4. The process of combining the corrected media image data and the print target image data is The processor sets, for a specific area corresponding to white or transparent pixels in the image data to be printed, the pixel data of the specific area in the corrected media image data as the pixel data of the specific area after synthesis, and The processor sets, for an area other than the specific area, data obtained by synthesizing the pixel data of the area other than the specific area in the corrected media image data and the pixel data of the area other than the specific area in the image data to be printed as the pixel data of the area other than the specific area after synthesis. The image processing method according to claim 1 or claim 2 includes the above processes.

5. The processor derives a brightness comparison value representing the comparison result between the maximum media brightness and the maximum output brightness, and When the brightness comparison value is outside a predetermined allowable range, the processor generates the composite image data by synthesizing the corrected media image data and the image data to be printed, and When the brightness comparison value is within the allowable range, the processor generates the composite image data by synthesizing the media image data and the image data to be printed. The image processing method according to claim 1 or claim 2 is as described above.

6. An image processing apparatus comprising a processor that realizes the image processing method according to claim 1 or claim 2.

Images