JP2011076394A - Printer, printing program and printing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a printer, a printing program and a printing method improving the image quality of a print result. <P>SOLUTION: In printing based on image data composed of at least main image data MID for printing a main image and background image data BID for printing a background image, an overlap of the main image MI and the background image BI when printed on a print medium is detected, and the background image data BID is corrected based on the detection result, to correct the overlapped background image data BID. Printing is performed to the print medium in a predetermined order, based on the corrected background image data BID and main image data MID. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a printing apparatus, a printing program, and a printing method, and more particularly to a printing apparatus, a printing program, and a printing method that print on a printing medium based on image data.

  Improvement of print image quality is an essential issue in a printing apparatus. Conventionally, the generation ratio of dark ink and light ink is adjusted according to the tone value of image data (see, for example, Patent Document 1), and printing / colorimetric conditions Various devices have been devised, such as providing a correction table to be referred to when compensating for color misregistration due to the difference between them (see, for example, Patent Document 2).

JP 2004-291459 A JP 2008-72366 A

  In recent years, printing of images on printing media other than white (such as transparent media) with a printing apparatus has been increasing. When printing on such a print medium, in order to improve the color reproducibility in the print result of the color image that forms the main image on the print medium, a background image that is a base in advance in the area where the color image is printed May be printed. As the background image, not only a solid white image but also a color image or a gradation image having a color component to be printed using a color ink such as CMYK is used. Thus, the technique of printing a plurality of images in duplicate at the same location has not yet matured, and further improvement in image quality has been desired.

  The present invention has been made in view of the above problems, and includes a case where the first image data and the second image data are present, and the second image is provided at a position overlapping the print position based on the first image data. An object of the present invention is to provide a printing apparatus, a printing program, and a printing method capable of improving the image quality of a printing result when printing based on data.

  In order to solve the above-described problems, a printing apparatus according to the present invention has at least a predetermined value based on image data including first image data for printing a main image and second image data for printing a background image. A printing apparatus for printing on a print medium, the detection means for detecting an overlap portion of the main image and the background image when printed on the print medium, and the overlap portion by correcting the second image data Image correction means for correcting the background image, and printing of the main image based on the first image data and printing of the background image based on the second data on the print medium in a predetermined order. And a printing unit that performs printing.

  In the above configuration, the main image and the background image are printed on the same print medium by the printing unit. The print result is observed in a state where the main image and the background image are superimposed. The main image is formed in a layer closer to the observer, and the background image is formed in a layer farther from the observer than the main image. Therefore, in the region where the main image and the background image are formed overlappingly, the background image can be seen through depending on the color material density when the main image is formed. It will be observed as a mixed color.

  In order to prevent such a change in the appearance of the main image due to color mixing, the detecting means first detects an overlapping portion of the main image and the background image. The overlapping portion of the main image and the background image may be an overlapping region of the print areas of the first image data and the print area of the second image data, or the ink or It may be an overlapping area between a region where a color material such as toner adheres to the print medium and a region where the color material such as ink or toner actually adheres to the print medium based on the second image data. Since the latter has fewer overlapping portions, the background image correction in the image correction means can be executed in a pinpoint manner.

  The object to be corrected by the image correcting means may be a main image or a background image, but the main image is often more important than the background from the viewpoint of importance in the print result, and the image is corrected. Therefore, it is preferable to use the background image as a correction target in order to avoid the degradation of the image quality that occurs as a result. Also, the background image is often a monotonous image, and it is more efficient to correct the background image. In this way, by providing a means for correcting one of the images that are duplicately printed, it is possible to perform a correction that prevents deterioration in image quality due to the duplicate printing. Therefore, it is possible to improve the image quality of the print result.

  As a selective aspect of the present invention, the image correcting unit may correct the overlapping portion of the background image to a white image. By changing the corresponding portion of the background image to a white image, the main image is not affected by the background image. Further, the main image can be formed as a printing result as intended by the creator regardless of the type of printing medium (white paper, transparent film, etc.). Note that even if the white image is converted into a white image that is printed with a coverage that covers the front surface of the print medium at the corresponding location, the main image can be more reliably formed as a print result as intended by the creator. become.

  As a selective aspect of the present invention, a color variation allowable value indicating whether or not color variation in a printing result is permitted is set in the first image data. When the color variation of the main image at the overlapping portion is not allowed in the data, the background image at the overlapping portion is corrected, and the main image at the overlapping portion in the first image data is corrected. When the color variation of the image is permitted by the color variation allowable value, the background image at the overlapping portion may not be corrected. In other words, if the creator creates the main image with the background image appearing transparent, it is not necessary to change the color appearance. There is no need to perform the image correction processing. Therefore, it is possible to improve the image quality while reliably reflecting the intention of the creator.

  As a selective aspect of the present invention, the image correction means may be configured to detect the overlapping portion when the main image at the overlapping portion is a specific color set in advance so as not to allow color variation in the printing result. The background image may be corrected. In other words, even if the creator does not explicitly specify it, color variation can be prevented for a specific color that is known in advance to not allow color variation. In order to prevent such a color variation of the specific color, the color variation allowable value can be automatically set in advance to a value that does not allow the color variation.

  As a selective aspect of the present invention, the image correction means may include a color color component at the overlapping portion of the background image and a color color component at the overlapping portion of the main image. The overlapping portion is corrected, and when the background image has a color color component and the overlapping portion of the main image does not have a color component, the overlapping portion of the background image is not corrected, and the background image When there is no color color component in the overlapping portion, the overlapping portion of the background image may not be corrected. That is, if a color color component is not included in a corresponding overlapping portion of the main image, color variation does not occur in the main image, and if a color color component is not included in the overlapping portion of the background image, Color variation does not occur. Therefore, in such a case, the image quality can be improved more appropriately by preventing the image from being corrected.

  As a selective aspect of the present invention, the image correcting unit may correct the background image of a portion corresponding to a portion where the ink recording rate of the first image data exceeds a predetermined ratio. In other words, even if color variation is allowed at the corresponding overlapping portion of the main image, if the ink recording rate of the main image has already reached the limit of the ink fixing amount, printing a background image at that portion causes printing unevenness and graininess. This results in a deterioration of sex. Therefore, even in such a case, the image quality can be further improved by correcting the image.

  The above-described printing apparatus includes various modes such as being implemented in a state of being incorporated in another device or being implemented together with another method. The present invention also provides a printing system including the printing apparatus, a printing method and a printing control method having steps corresponding to the configuration of the apparatus described above, a printing program for causing a computer to realize a function corresponding to the configuration of the apparatus described above, and the printing It can also be realized as a computer-readable recording medium on which a program is recorded. The inventions of these printing system, printing method, printing control method, printing program, and medium on which the printing program is recorded also have the above-described operations and effects. Needless to say, the configurations described in claims 2 to 6 are also applicable to the system, the method, the program, and the recording medium.

It is explanatory drawing which showed the schematic structure of the printing apparatus. It is the block diagram which showed the hardware constitutions of PC. FIG. 2 is a block diagram illustrating a hardware configuration of a printer. FIG. 2 is a block diagram illustrating a software configuration of a printing apparatus. It is explanatory drawing which showed the main image and the background image notionally. It is explanatory drawing which showed an example of the combination of main image data and background image data. It is explanatory drawing which showed the other example of the combination of main image data and background image data. 6 is a flowchart illustrating a flow of printing processing executed by a printer driver. It is explanatory drawing which showed an example of the color conversion table LUTm partially. It is the figure which showed partially an example of the correspondence of color conversion table LUTb. It is explanatory drawing which shows an example of the control command produced in print data creation processing. 6 is a flowchart illustrating a flow of a second embodiment of a printing process executed by a printer driver. It is a figure explaining a forward model converter. It is explanatory drawing which showed an example of the inverse model LUT_inv. 10 is a flowchart illustrating a flow of a third embodiment of a printing process executed by a printer driver. 5 is a flowchart of print processing executed by a printer. It is explanatory drawing which shows the detailed structure of a raster buffer and a head buffer. It is explanatory drawing which shows the structure of the print head of a printer.

Hereinafter, embodiments of the present invention will be described in the following order.
(1) Configuration of the present embodiment:
(2) Printing process by printer driver:
(3) Printing process on the printer:
(4) Modification:
(5) Summary:

(1) Configuration of the present embodiment:
FIG. 1 is an explanatory diagram schematically showing a configuration of a printing apparatus according to the present embodiment. In the figure, the printing apparatus of the present embodiment includes a printer 100 and a personal computer 200 (PC 200). The printer 100 is an ink jet printer that discharges ink to form an image on a print medium. The PC 200 functions as a print control apparatus that causes the printer 100 to perform printing by outputting print control data including image data for printing, control commands, and the like to the printer 100. The printer 100 and the PC 200 are communicably connected via a communication cable, a wireless communication line, or the like.

  The printer 100 according to the present embodiment uses a total of seven ink colors, cyan (C), magenta (M), yellow (Y), black (K), light cyan (lc), light magenta (lm), and white (W). It is mounted and printing is performed using ink of a color appropriately selected from these. In other words, the printer 100 uses W ink to perform printing to form a white or near-white background on the print medium, print a color image, or place the background and the color image in a predetermined order. Duplicate printing is possible.

(1-1) Hardware configuration:
FIG. 2 is an explanatory diagram schematically showing the configuration of the PC 200. As shown in the figure, the PC 200 includes a CPU 205, a RAM 210, a ROM 215, a display interface 225 (DIF 225), an operation input device interface 230, a hard disk 235 (HD 235), and a USB interface 240. The units 205 to 230 are connected via a communication line such as a bus, and can communicate with each other under the control of a control controller such as a chip set. A display 225a as a display device is connected to the display interface 225. The operation input device interface 230 is connected with a mouse and a keyboard as the operation input device 230a. The USB interface 240 can communicate with the USB interface 155 of the printer 100.

  FIG. 3 is an explanatory diagram schematically showing the configuration of the printer 100. As shown in the figure, the printer 100 includes a CPU 105, a RAM 110, a ROM 115, a print head 120, a head controller 125, a carriage on which ink tanks of each color CMYKlclmW are mounted, a carriage controller 135, a carriage motor 140, a print medium feed motor 145, A print medium feed controller 150 and a USB interface 155 are provided. Each part 105,110,115,125,135,150,155 is connected via communication lines, such as a bus | bath, and can mutually communicate according to control of control controllers, such as a chipset. The CPU 105 functions as a control unit for controlling the entire printer 100 by performing arithmetic processing according to the program while appropriately using the RAM stored in the ROM 115 as a work area.

  The print head 120 includes a group of nozzles that eject ink, and is mounted on a carriage. The carriage motor 140 is a drive mechanism that moves the carriage in a predetermined direction (main scanning direction), and operates according to the control of the carriage controller 135. The print medium feed motor 145 is a drive mechanism that transports the print medium in a direction orthogonal to the main scanning direction (sub-scanning direction), and operates according to the control of the print medium feed controller 150. Each nozzle of the print head 120 is arranged so as to correspond to the ink tank of each color. Under the control of the head controller 125, the color ink is acquired from the corresponding ink tank and discharged. The controller forms an image on the print medium by controlling the carriage controller 135, the print medium feed controller 150, and the head controller 125 in conjunction with each other.

(1-2) Software configuration
FIG. 4 is an explanatory diagram schematically showing a software configuration of the printing apparatus. As shown in the figure, the HD 235 of the PC 200 includes an application program APL and a printer driver PDrv, a main image color conversion table LUTm, a background image color conversion table LUTb, a main image halftone resource HTRm, and a background image. A halftone resource HTRb is stored.

<Application>
The application program APL is an application program that creates image data of an image to be printed on a print medium such as a transparent film and outputs the image data to a printer driver. As such application programs, there are various programs such as an application for processing and correcting an image like a retouch program, an application for drawing an image on a computer like a draw program, and an application for creating a document like word processing software. Applicable.

  It is assumed that the application program APL can adjust a main image representing an image or document itself and a background image representing a background of the image or document. The application program APL has a function of creating image data corresponding to each of the main image and the background image and outputting the image data to the printer driver. In the present embodiment, the image data corresponding to the main image is designated as main image data MID (if there are a plurality of main image data, “first”, “second”... Are added as appropriate, and the code is “MID1”. , “MID2”, etc.), image data corresponding to the background image data is assigned background image data BID (if there are a plurality of background image data, “first”, “second”... The code is “BID1”, “BID2”, etc.).

In this embodiment, the main image data is composed of a combination of gradation values of CMYK color data, and the background image data is gradation values of white (W) density in addition to the gradation values of CMYK color data. It is comprised by the density value T which shows. In the present embodiment, description will be made by adopting four colors of CMYK as color data. However, the color data is not limited to the combination of CMYK, and RGB data represented by three primary colors of RGB or L ^* a. Lab data represented by each value of ^* b ^* may be used.

The names “main image” and “background image” are not necessarily limited to those having a master-slave relationship in which one is a main image and the other is a subordinate image. It is only a name determined according to the printing order when printing and the observation direction assumed for the printing result.
FIG. 5 is an explanatory diagram conceptually showing a main image and a background image. As shown in FIG. 5 (a), for example, by first printing a "background image" on a printing medium such as a transparent film and then printing a "main image", the image is observed from the printing surface side of the printing medium. The background image is printed as a background when the image is printed, and the main image is formed on the front side of the background image.
In addition, as shown in FIG. 5B, the “main image” was first printed on the transparent film, and then the “background image” was printed, which was observed from the non-printed surface side of the print medium. A background image is printed as a background, and a main image is formed on the front side of the background image.
Further, as shown in FIG. 5C, assuming that one surface of the printing medium is observed from the front surface, a “main image” is printed on the front surface and a “background image” is printed on the back surface. Thus, when viewed from the observation direction, the “background image” is printed as the background of the “main image”.
In FIGS. 5A to 5C, focusing only on the “background image”, when the “background image” is printed on the viewer side (surface background type), the “background image” is the opposite of the viewer. When printing on the side (back side background type), it can be classified.

The user selects which of the main image and the background image is printed first according to the usage of the printed matter. That is, if the printed material is observed from the printing surface side, the background image is designated to be printed first, and if the printed material is observed from the back surface side, the main image is designated to be printed first. Become. The application program APL generates printing order designation data POD including printing order designation data s for specifying the printing order designated by the user.
The application program outputs the print data PD including the main image data MID, background image data BID, and print order designation data POD created as described above to the printer driver PDrv.

  The main image data and the background image data may each be one image data, but may be composed of a combination of a plurality of image data. For example, when main image data is created by dividing it into a plurality of image layers, this corresponds to the case where each layer data is output as one image data.

FIG. 6 is an explanatory diagram showing an example of a combination of main image data and background image data. This figure shows an example in which main image data MID including main image MI, first background image data BID1 including background image BI1, and second background image data BID2 including background image BI2 are output from application program APL. .
In the figure, the main image data MID includes a character image “TEXT” as the main image MI. In the main image data MID, a setting value is set for each pixel or for each region by dividing the image into a plurality of regions and whether or not to allow color variation in the printing result. In the following description, this set value is referred to as “color variation allowable value”. If the “color variation allowable value” is set to “non-permitted”, the background images BI1 and BI2 are used so that the color appearance of the print result does not change regardless of the background images BI1 and BI2. A process for adjusting the image data to remove the influence is performed. On the other hand, if the “color variation allowable value” is set to “allowable”, the process of adjusting the colors of the background images BI1 and BI2 is not performed.

This “color variation allowable value” can be provided as a new parameter in normal image data, but a parameter used in image data that is generally used at present can also be used.
For example, transmission information TI such as an α channel used in general-purpose applications such as Photoshop can be used. The transmission information TI is set for each pixel of the main image data and is information indicating transmission / non-transmission of the background image. That is, “allowable” and “non-permissible” color variation allowable values are parameters corresponding to complete transmission (transmittance 100%) and complete non-transmission (transmittance 0%). In order to set the transmittance to any value between 0 and 100% in the α channel, the color variation tolerance can be set to any degree between “allowable” and “non-allowable”. It may be possible to specify the degree to which the influence from the background is allowed. As an example of setting the degree of allowing the influence from the background, a case where the transmittance is set to an arbitrary value between 0 and 100% in the α channel is described in a later-described modification.

The “color variation allowable value” may be determined according to an analysis result obtained by analyzing the main image data MID. For example, by scanning each pixel data of the entire main image data MID and analyzing the image feature amount, what kind of image the main image data MID is (a binary image, an image created by computer graphics, a photograph, etc.) Image, an image including a specific color that does not allow color variation such as a corporate color, a document image, etc.), and a color variation allowable value can be set according to the image type.
For example, if the main image data MID is a binary image, an image created by computer graphics, or an image including a specific color that does not allow color variation, such as a corporate color, the color is strictly set when creating the image data. The color variation allowable value is set to “non-permitted”. If the image is a photographic image, it is determined that printing that is not affected by the background is desired, and the color variation allowable value is set to “non-permissible”. On the other hand, if it is a document image, it is determined that some color variation is allowed, and is set to “allow”. Of course, these are only examples, and the image type that is “permitted” and the image type that is “non-permitted” may be reversed, and the color variation allowable value is set for each image type as desired by the user. It may be possible to set in advance using a UI or the like.

  In FIG. 6, the first background image data BID1 represents a gradation image as the background image BI1 composed of colors other than white. That is, the first background image data BID1 is a background image printed with CMYKlclm ink other than W ink. In FIG. 6, the first background image data BID <b> 1 is an image that gradually becomes darker as it approaches the right edge of the image.

In FIG. 6, the second background image data BID2 represents the background image BI2 composed of a white image, and the white density, that is, the ink recording rate and the ink coverage of white ink are designated for each pixel. Image data. That is, the second background image data BID2 is a background image that is printed with only W ink without using CMYKlclm ink. FIG. 6 shows an image created so that the density of the white image is different for each part of the image. The left half of the image has N% of the density of the white image, and the middle of the image to the right quarter. The density up to 1% is M%, and the density of the right quarter of the image is P%.
In the first and second embodiments of the printing process described later, the influence of the background image BI1 and the background image BI2 on the main image MI is taken into account when printing the image data of FIG. 6 described above as input data. However, an example of printing performed will be described.

FIG. 7 is an explanatory diagram showing another example of a combination of main image data and background image data. This figure shows an example in which the first main image data MID1, the second main image data MID2, the first background image data BID1, and the second background image data BID2 are output from the application program APL. The first main image data MID1 and MID2 are image data created in layers and each output as one image data.
In FIG. 7, the first main image data MID1 includes a character image “TEXT” as the first main image MI1, and each pixel constituting the character image is set to be completely transparent. On the other hand, the second main image data MID2 includes a predetermined color image as the second main image, and each pixel constituting the color image is set to be completely non-transparent. The first background image data BID1 and the second background image data BID2 are the same as in FIG.
In these first main image data MID1 and MID2, the first main image data MID1 is created as an upper layer and the second main image data MID2 is created as a lower layer. The main image data MID1 and MID2 are combined into one image data during the printing process, and are printed as one image data when output to the printer 100. However, since the transparency setting for the lower layer is set for each image data, it is necessary to consider the influence of the background image on each image data before the composition.
In a third embodiment of the printing process described later, an example of printing performed while considering the influence of the background image on the main image when printing each image data shown in FIG. 7 as input data will be described.

<Printer driver>
As shown in FIG. 4, by executing a printer driver program of the printer 100 on basic software such as operating software in the PC 200, an image data acquisition unit M1, an influence determination unit M2, an influence removal unit M3, a color conversion unit M4, Functions corresponding to the modules of the halftone processing unit M5, the print data creation unit M6, and the forward model converter M7 are realized. In addition, when a control program such as firmware is executed by the control unit of the printer 100, a function corresponding to the command processing unit M11 is realized.

  The influence determination unit M2 determines whether or not the color of the main image MI printed based on the main image data MID varies under the influence of the background image BI printed based on the background image data BID. It is a module. When the main image MI fluctuates due to the influence of the background image BI, the influence determination unit M2 instructs the influence removal unit M3 to perform processing for removing the influence. The influence determination is performed, for example, in units of pixel data of main image data MID and background image data BID, and can be performed by comparing pixel data used for printing at the same position on the print medium.

  Specifically, the pixel data of the main image data MID has color components other than white (hereinafter referred to as “color color components”), and is located at the same position as the pixel data. When the pixel data of the background image data to be printed has a color component, it is determined that the color of the background image BI affects the color of the main image MI. Having a color component means that the gradation value of at least one color of CMYK is not zero. In addition, the pixel data of the main image data MID has a color component, and the pixel data of the background image data BID printed at the same position as the pixel data does not have a color component. Can be determined to have no effect. Further, when the pixel data of the main image data MID does not have a color component, it is possible to determine that there is no influence because there is no subject to be affected. Of course, if the color color component of the pixel data of the background image data BID is less than an allowable amount that can be regarded as a minute amount (if the gradation value of the pixel data and the amount of ink generated thereby are less than a predetermined amount), It may be determined that the main image MI is not affected.

The influence removing unit M3 corrects at least one of the background image data BID and the main image data MID so as to remove the influence of the background image BI on the main image MI or to keep the influence within a permissible range. adjust.
When correcting the background image data BID, for example, the gradation value of each color of CMYK of the corresponding pixel data is changed to 0, or the ink amount data B_ink of each color ink created based on this gradation value is set to 0. By changing it, the influence of the background image BI on the main image MI can be removed. Of course, instead of changing the gradation value to 0, the color data representing the color component included in the pixel data may be changed within an allowable range. A specific method for correcting the background image data BID will be described in a first embodiment described later.
When correcting the main image data MID, for example, by adjusting the main image data MID so that the color tone in the printing result formed by the color data of the color component of the background image data BID is offset, The influence of the background image BI on the image MI can be removed. A specific method for correcting the main image data MID will be described in a second embodiment described later.

  The color conversion unit M4 appropriately refers to the color conversion tables LUTm and LUTb stored in advance in the HD 235, and sets the gradation values of the CMYK colors of the main image data MID and the background image data BID for each ink mounted on the printer 100. Convert to color gradation value. The gradation value of each ink color is a value proportional to the amount of ink taken out from the nozzle of the print head within a range corresponding to each pixel, and is also called an ink recording rate. The color conversion unit M4 is configured to simultaneously perform so-called color separation processing for distributing light ink, dark ink, and gradation values of the same color.

The halftone processing unit M5 binarizes the gradation value generated for each ink color for each pixel, ink ejection / non-ejection, with reference to the halftone resources HTRm and HTRb stored in advance in the HD 235 as appropriate. At the same time, halftone image data specifying the amount of ink to be ejected is generated.
The print data creation unit M6 receives the halftone image data and rearranges the data in the order used by the printer 100, and sequentially outputs the data to the printer 100 in units of data used in one main scan.

(2) Printing process by printer driver:
(2-1) First Embodiment of Print Processing:
FIG. 8 is a flowchart showing the flow of printing processing executed by the printer driver PDrv. In the printing process shown in the figure, printing is performed based on print data PD composed of main image data MID, first background image data BID1, second background image data BID2, and print order designation data POD. At this time, if the print range overlaps between the main image data MID and the first background image data BID1, or between the main image data MID and the second background image data BID2, the first background image data for the overlapping portion. BID1 and second background image data BID2 are corrected. As a result, the print result is corrected to match the intention of the user who created the print data PD. In the printing process according to the first embodiment, the main image data MID is not corrected.

  The printing process of the first embodiment is started when print data PD is input from the application program APL. When the process is started, in step S100 (hereinafter, “step” is omitted), the image data acquisition unit M1 receives the main image data MID input from the application program APL and the first background image data BID1. Second background image data BID2 and printing order designation data POD are acquired.

  In step S105, the influence determination unit M2 affects the appearance (color reproduction) of the print result printed by the main image data MID, with the print results of the first background image data BID1 and the second background image data BID2. Determine whether or not. More specifically, first pixel data M_Pix is sequentially selected from a plurality of pixel data constituting the main image data MID, and is used for printing at the same position as the pixel data M_Pix. The pixel data B1_Pix of the image data BID1 and the pixel data B2_Pix of the second background image data BID2 are selected and acquired. Then, it is determined whether or not the printing result based on the pixel data B1_Pix and B2_Pix affects the printing result based on the pixel data M_Pix.

Whether or not to influence is determined by the following plurality of methods.
First, the influence determination unit M2 determines whether each of the pixel data B1_Pix and the pixel data B2_Pix has a color color component, and then determines whether the pixel data M_Pix has a color color component. To do.

If the pixel data B1_Pix, B2_Pix is composed only of white, the influence determination unit M2 determines that the background images BI1 and BI2 do not affect the main image MI and proceeds to S120.
Even when the pixel data B1_Pix and B2_Pix have a color component, if the pixel data M_Pix does not have a color component, the influence determination unit M2 determines that the background images BI1 and BI2 It is determined that the main image MI is not affected, and the process proceeds to S120.
On the other hand, when at least one of the pixel data B1_Pix and B2_Pix has a color component, and the pixel data M_Pix has a color component, at least one of the background images BI1 and BI2 is the main image. It is determined that there is a possibility of affecting the image MI, and the process proceeds to S110.

  In S105, a determination branch is made based on whether or not the CMYK color data of the pixel data B1_Pix and B2_Pix of the background image is 0. However, if the color data components of the background image pixel data B1_Pix and B2_Pix are very small Considering that the influence on the main image is small, the determination branch may be performed depending on whether or not it has a color color component equal to or smaller than a predetermined threshold value indicating the minute amount. The predetermined threshold value can be determined experimentally, for example, by actually performing printing and determining each color data or determining each color data combination.

However, when the pixel data M_Pix is pixel data constituting a specific image specified in advance, there is an influence regardless of whether or not the color color component of the pixel data B1_Pix and B2_Pix of the background image is very small. It is preferable to proceed to S110 by judging that there is.
For example, when the pixel data M_Pix is color data for printing a color of a specific color (when the ratio of CMYK color data is a specific ratio), the color data components of the background image pixel data B1_Pix and B2_Pix are Even if the amount is very small, it is preferable to proceed to S110 and remove the influence of the pixel data B1_Pix, B2_Pix of the background image on the pixel data M_Pix of the main image. The specific color referred to here is, for example, a corporate color (symbol color), which is a color that requires printing with strictly fixed colors, and is a color that is designated in advance so as not to allow color variation.
Even when the pixel data M_Pix is a pixel constituting a part of a binary image or a pixel constituting a part of a figure drawn by a computer, the color data of the pixel data B1_Pix and B2_Pix of the background image It is preferable to determine that there is an effect regardless of whether or not the amount of the component is very small and proceed to S110. In the main image data MID, a parameter indicating whether or not the image is a graphic image drawn by a computer and a parameter indicating whether or not the image is a binary image are set.

  In S110, the influence determination unit M2 refers to the transmission information TI of the pixel data selected in S105, and determines whether or not the pixel data M_Pix selected in S105 is a transmission setting. That is, it is determined whether or not the setting allows the main image MI to be affected by the background images BI1 and BI2. The background images BI1 and BI2 may affect the main image MI as long as the background images BI1 and BI2 are image data created in advance assuming that they appear in the print result through the main image MI. It is. The influence determination unit M2 proceeds to S120 if the transmission information TI of the pixel data M_Pix selected in S105 is set to be transparent, and proceeds to S115 if the pixel data M_Pix selected in S105 is set to be non-transparent.

In S115, the influence removing unit M3 corrects the color of the pixel data B1_Pix and B2_Pix selected in S105 so as to minimize the influence on the main image. In the first embodiment, the influence removing unit M3 performs a process of removing color color components from the pixel data B1_Pix and B2_Pix selected in S105. In other words, the influence removing unit M3 changes the CMYK color gradation value of the color data constituting the pixel data B1_Pix to 0, excluding the white data. Further, the influence removing unit M3 changes the density gradation value of the white data constituting the pixel data B2_Pix to 100%, and changes the white solid to be printed by the pixel data B2_Pix.
The above processes of S105 to S115 are sequentially executed until all pixel data of the main image data MID and the first background image data BID1 and the second background image data BID2 are selected in S105.
By performing the processes of S105 to S115, it is possible to prevent the background images BI1 and BI2 from affecting the appearance of the main image MI in the print result printed based on the print data PD.

  In S120, the color conversion unit M4 creates ink amount data M_ink of the main image from the main image data MID. That is, the color conversion unit M4 selects one pixel data M_Pix from the main image data MID, refers to the color conversion table LUTm, and converts each pixel data M_Pix of the main image data MID to the gradation value for each ink color. Is converted into ink amount data (tone value for each ink color). As described above, in this embodiment, printing is performed using CMYKlclmW inks of a total of seven colors. Therefore, in the color conversion process of S120, the CMYK values are converted into the respective tone values of the seven ink colors with reference to the color conversion table LUTm.

  FIG. 9 is an explanatory diagram partially showing an example of the color conversion table LUTm. As shown in the figure, the color conversion table LUTm defines the correspondence between preset CMYK values and gradation values of CMYKlclm, which are ink colors. In the color conversion table LUTm shown in the figure, the gradation value of each color data of CMYK is defined in the range of 0 to 100, and the gradation value of the ink color is defined in the range of 0 to 255. ing. Also, as shown in FIG. 9, in this embodiment, six inks of CMYKlclm are used for the ink amount data generated by conversion from the main image data MID, and W ink is not used.

  In S125, the influence determination unit M2 determines the influence of the background images BI1 and BI2 on the main image MI based on the ink amount data M_ink of the main image. If it is determined that there is an influence, the process proceeds to S130 and there is no influence. If it is determined, the process proceeds to S135. The influence determined here is an influence regarding printing unevenness and deterioration of graininess, and is determined based on the ink coverage of the ink amount data M_ink of the main image.

  More specifically, in S125, the influence determination unit M2 first selects and acquires one of the ink amount data M_ink of the main image or the pixel data M_ink_Pix, and performs solid printing when printing is performed using the pixel data M_ink_Pix. Judge whether to fill up or not. The determination of whether or not the image is solid is made based on whether or not the ink recording rate (ink coverage) of the pixel data M_ink_Pix exceeds a predetermined threshold value.

  That is, the influence determination unit M2 calculates the ink coverage based on the ink amount data of the pixel data M_ink_Pix, determines that the ink recording rate exceeds a predetermined threshold, determines that it is solid, and proceeds to S310. If the predetermined threshold value is not exceeded, it is determined that the solid filling is not allowed. If it is determined that the pixel data M_ink_Pix selected in S125 is not solid, the pixel data is sequentially selected until the solid filling determination is completed for all the pixel data of the ink amount data M_ink of the main image, and the solid filling in S125 is performed. When the determination is made and the solid filling determination is completed for all the pixel data of the ink amount data M_ink of the main image, the process proceeds to S135.

In S130, the influence removing unit M3 performs color compensation (color correction) on the pixel data M_Pix at the position corresponding to the pixel ink amount data M_ink_Pix selected in S125. In the present embodiment, the influence removing unit M3 performs a process of removing the color component from the pixel data B1_Pix selected in S125. That is, the influence removing unit M3 configures the pixel data B1_Pix of the first background image data BID1 and the pixel data B2_Pix of the second background image data BID2 printed at the position corresponding to the pixel ink amount data M_ink_Pix selected in S125. Among each color data, the gradation value of the color data excluding the white data is changed to 0. When the process of S130 is completed, pixel data is sequentially selected until the solid filling determination is completed for all the pixel data of the ink amount data M_ink of the main image, and the solid filling determination of S125 is performed, and all of the ink amount data M_ink of the main image is determined. When the solid filling determination is completed for the pixel data, the process proceeds to S135.
By performing the above processing, the first background image data BID1 and the second background image data BID2 become data that can prevent printing unevenness and deterioration of graininess in the printing result.

  In S135, the halftone processing unit M5 extracts the gradation value for each pixel of the ink color from the ink amount data M_ink of the main image, and performs binarization processing (halftone processing) with reference to the dither pattern for each ink color. Do. The binarization process is executed with reference to a preset main image halftone resource HTRm. Then, the halftone processing unit M5 sequentially extracts the gradation values for each ink color from the ink amount data M_ink of the main image and repeats the binarization process until the binarization process of S135 is performed for all ink colors. When the binarization process of S135 is completed for the gradation values for each ink color constituting the ink amount data M_ink of the main image, the binary data MBD of the main image is created.

In S140, composite background image data BID ′ obtained by combining the first background image data BID1 and the second background image data BID2 is created, and the color conversion unit M4 performs color conversion processing on the composite background image data BID ′, The halftone processing unit M5 performs halftone processing on the converted composite background image data BID ′.
FIG. 10 is a diagram partially showing an example of the correspondence relationship of the color conversion table LUTb that is referred to when the color conversion unit M4 performs color conversion of the background image data. As shown in the figure, in the color conversion table LUTb, the amount of white ink can be specified by the density value T. Also, the gradation value of each color data of CMYK is set as an input value of 0 to 15 between 0 and 100 so that it is suitable for printing a background image composed of lighter colors. Correspondence with ink amount is defined.
The color conversion unit M4 creates ink amount data B_ink of the composite background image by converting each pixel data of the composite background image data BID ′ into ink amount data while referring to the color conversion table LUTb, and the halftone processing unit M5 Binarization processing is performed on the gradation value for each ink color of each pixel of the ink amount data B_ink with reference to a dither pattern for each ink color, and binary data BBD of the composite background image data BID ′ is created. In this embodiment, the color conversion process and the halftone process are performed after the background image data is synthesized in advance. However, the composition may be performed after the color conversion of each background image data, or the halftone process. You may synthesize after finishing.

In S145, the print data creation unit M6 prints the main image MI and the background images BI1 and BI2 on the printer 100 based on the binary data MBD of the main image, the binary data BBD of the background image, and the print order designation data POD. Create a control command to In the following description, a case where a control command for causing the printer 100 to print the main image MI will be described as an example. However, a control command for causing the printer 100 to print a composite background image is also created by performing similar processing. Shall be.
FIG. 11 is an explanatory diagram illustrating an example of a control command created in the print data creation process. The control command includes a printing order designation command, a vertical position designation command, a horizontal position designation command, each dot data (raster data), and an ink code.

The print order designation command is created based on the print order designation data POD input from the application program APL.
FIG. 11A shows an example of a print order designation command. As shown in the figure, the print order designation command includes an identifier Esc indicating the head of the command, an identifier “j” indicating the print order designation command, and a command length (2 bytes in this embodiment) nL, nH. And printing order designation data s. For example, the value of the printing order designation data s is “0” when the printing order designation data POD indicates “MB printing”, and “1” when the printing order designation data POD indicates “BM printing”. ". “MB printing” means that the main image is printed first and the background image is printed later, and “MB printing” means that the background image is printed first and the main image is printed later. Means that. In this specification, the printing order designation data POD is created by the application program APL. However, the printing order designation data POD may be created by the printer driver PDrv, or the printing order created by the application program APL. The designated data POD may be corrected by the printer driver PDrv.

  The vertical position designation command is created based on the binary data MBD of the main image created corresponding to the main image data MID output from the halftone processing unit M5. The vertical position designation command is a command for designating a start position of an image in the vertical direction (sub-scanning direction: print medium conveyance direction). The vertical position designation command is created as a command common to all inks.

  The horizontal position designation command is a command for designating the image formation start position in the horizontal direction (main scanning direction) for one ink color during main image formation. The horizontal position designation command is generated for each ink color of the binary data MBD of the main image output from the halftone processing unit M5. The print data creation unit M6 refers to the binary data for one ink color, specifies the start position of the binary data MBD of the main image for the one ink color in the horizontal direction, and designates this start position. Create a horizontal position specification command for

  FIG. 11B shows an example of a raster command. As shown in the figure, the raster command includes an identifier Esc indicating the head of the command, an identifier i indicating the raster command, an ink code r, a bit number b per pixel, and a horizontal direction (X direction). Length (2 bytes in this embodiment) nL, nH, vertical (Y direction) length (2 bytes in this embodiment) mL, mH, raster data (dot data) d1, d2,. ., Dn. Dot data is created for each raster. The ink code r is a code unique to each ink color. The HD 235 stores an ink code table in which an ink abbreviation unique to each ink color is associated with an ink code. By referring to the ink code table, an ink code of each ink color is searched for, and a raster command is stored. Ink cords to be applied to can be obtained.

  In S150, the printer driver PDrv transmits the print control data (print order designation command, vertical position designation command, horizontal position designation command, raster command) and background image print control data generated in S145 to the printer 100. To do. This completes the processing by the printer driver PDrv.

(2-2) Second Embodiment of Print Processing:
FIG. 12 is a flowchart showing the flow of printing processing executed by the printer driver PDrv. In the printing process shown in the figure, printing is performed based on print data PD composed of main image data MID, first background image data BID1, second background image data BID2, and print order designation data POD. At that time, if the print range overlaps between the main image data MID and the first background image data BID1, or between the main image data MID and the second background image data BID2, the main image data MID is set for the overlapping portion. Correct it. As a result, the print result is corrected to match the intention of the user who created the print data PD. In the printing process of the second embodiment, the first background image data BID1 and the second background image data BID2 are not corrected.

  The printing process of the second embodiment is started when print data PD is input from the application program APL. When the process is started, in S200, the image data acquisition unit M1 acquires the main image data MID, the first background image data BID1, the second background image data BID2, and the printing order designation data POD input from the application program APL. To do.

  In step S205, the influence determination unit M2 affects the appearance (color reproduction) of the print result printed by the main image data MID, with the print results of the first background image data BID1 and the second background image data BID2. Determine whether or not. The determination method in this determination process is the same as in the first embodiment. If the influence determination unit M2 determines that there is an influence, the process proceeds to S210, and if it determines that there is no influence, the process proceeds to S220.

  In S210, the influence determination unit M2 refers to the transmission information TI of the pixel data selected in S205, and determines whether or not the pixel data M_Pix selected in S205 is a transmission setting. The influence determination unit M2 proceeds to S220 when the transmission information TI of the pixel data M_Pix selected at S205 is set to be transparent, and proceeds to S215 when the pixel data M_Pix selected at S205 is set to be non-transparent.

  In S215, the influence removing unit M3 corrects the pixel data M_Pix selected in S105 to a color that takes into account the influence received by the color color component of the pixel data B1_Pix of the background image. In the second embodiment, since the second background image data BID2 does not have a color component, it is not considered in S215. However, if it has a color component, the second background image data BID2 is also considered. The influence removing unit M3 roughly corrects the pixel data M_Pix in the complementary color direction, thereby correcting the pixel data to cancel out the color influence of the pixel data B_Pix. In the present embodiment, an example is described in which the color appearance on the printed material when actually printed is corrected so that the pixel data matches the appearance when the main image data MID is printed on the white printed material. To do.

  FIG. 13 is an explanatory diagram of a method for removing the influence of the background image by correcting the main image. First, the influence removing unit M3 converts the pixel data M_Pix into ink amount data with reference to the color conversion table LUTm, and converts the pixel data B1_Pix and pixel data B2_Pix into ink amount data with reference to the color conversion table LUTb. Each ink amount data is input to the forward model converter M7 to be converted into data in the CIELAB color system.

FIG. 14A is a diagram for explaining the forward model converter M7. As shown in the figure, the forward model converter M7 includes a spectral printing model converter M71 and a color calculation unit M72. The “forward model” means a conversion model that converts the ink amount into a color value (colorimetric value) of the device independent color system. In the second embodiment, the case where the CIE-Lab color system is adopted as the device independent color system is described as an example. In the following description, the color value of the CIE-Lab color system is simply referred to as “L ^* a ^* b ^* value” or “Lab value”.

As shown in FIG. 14 (a), the spectral printing model converter M71 that forms the preceding stage of the forward model converter M7 has the spectral reflection of color patches printed according to the ink amount data of a plurality of types of ink. Convert to rate R (λ). In this specification, the term “color patch” is used in a broad sense including not only a chromatic color patch but also an achromatic color patch. In the present embodiment, a color printer that can use six types of color inks CMYKlclm is assumed, and the spectral printing model converter M71 also receives the ink amounts of these six types of color inks. However, an arbitrary ink set can be used as the plurality of types of ink used in the printer.
The color calculation unit M72 calculates a Lab value from the spectral reflectance R (λ). In calculating the Lab value, a preselected light source (for example, standard light D50) is used as a color patch observation condition.
As a method for creating the spectral printing model converter M71, for example, a method described in JP-T-2007-511175 can be employed.

By entering the ink amount data corresponding to each pixel data of the above forward model converter M7, pixel data M_Pix is converted into Lab values of ^{_{L * 1 a * 1 b *}} 1, pixel data B1_Pix the ^L _* 2 a ^* that ₂ b ^* ₂ and those converted into Lab values.
Next, the influence removing unit M3 searches for pixel data that minimizes the objective function shown in the following (1) from pixel data expressed by an arbitrary combination of gradation values of CMYK colors. Here, the pixel data is data expressed by gradation values for expressing the main image data MID.

In the above _{^{(1), L * 1 a * 1 b}} * 1 is the Lab values when converting the pixel data M_Pix selected in S105 by the forward model converter _{^{M7, L * x a * x}} b * x is This is a Lab value when a combination of arbitrary CMYK gradation values that the main image data MID can take is converted by the forward model converter M7. The objective function of equation _{^{(1), L * x a * x b}} * x
And the sum of the _{^{L * 2 a * 2 b *}} 2, the difference between the _{^{L * 1 a * 1 b *}} 1 are adapted to minimize the. That ^is, the color appearance when printed on the basis of the _{^{L * x a * x b *}} x of the forward model converter M7 pixel data B1_Pix while printing the main image with the underlying CMYK values of conversion by the pixel data M_Pix When the color appears closest to the color when printed on a white print medium, it is minimized.

Effect removal unit M3 is converted into Lab values by entering a combination of CMYK tone value the main image data MID can take sequentially forward model converter M7, resulting ^{_{L * x a * x b *}} x sequentially the By substituting into the equation (1), evaluation values for each combination of CMYK gradation values are sequentially calculated. The effect removal unit M3 is a combination of CMYK gradation values evaluation value corresponds to the minimum ^{_{L * x a * x b *}} x in the calculated evaluation value, i.e., to minimize the objective function CMYK Search for a combination of gradation values. The effect removal unit M3 uses the combination of CMYK gradation values calculated in this way as new pixel data of the pixel data M_Pix selected in S205. Minimizing the objective function ^{_{E L * x a * x b}} * x ^corresponds to the color shifting the ^{_{L * 1 a * 1 b *}} 1 in the complementary direction.

  Note that the influence removing unit M3 may convert the Lab value at which the evaluation value is minimized by the forward model converter M7 into the ink amount data as it is instead of correcting the pixel data M_Pix. In this case, the influence removing unit M3 calculates the ink amount data from the Lab value with reference to the inverse model LUT_inv. That is, the ink amount data M_ink corresponding to the main image data MID is generated without performing the color separation process of the main image data MID executed in S220 described later.

FIG. 14B is an explanatory diagram showing an example of the inverse model LUT_inv. The “inverse model” means a conversion model that converts a color value of the device independent color system into an ink amount. As shown in the figure, the inverse model LUT 410 is a look-up table in which an L ^* a ^* b ^* value is input and an ink amount is output.
For example, the LUT 410 divides the L ^* a ^* b ^* space into a plurality of small cells, and selects and registers an optimum ink amount for each small cell. This selection is performed in consideration of, for example, the image quality of the color patch printed with the ink amount. In general, there are many combinations of ink amounts that reproduce a certain L ^* a ^* b ^* value. Therefore, in the LUT 410, an ink that has an optimum ink amount selected from a desired viewpoint such as image quality is registered from among a large number of ink amount combinations that reproduce substantially the same L ^* a ^* b ^* value. As a method for creating the LUT 410 by selecting an optimal ink amount for each small cell, for example, the method described in the Japanese translations of PCT publication No. 2007-511175 can be employed.

The processes of S205 to S215 are sequentially executed until all pixel data of the main image data MID are selected in S205.
By performing the above processing, it is possible to prevent the main image printed by the main image data MID from becoming a color not intended by the producer due to the influence of the base image.

  In S220, the color conversion unit M4 selects one pixel data M_Pix from the main image data MID, refers to the color conversion table LUTm, and converts the main image data M_Pix to a main image that is a gradation value for each ink color. Ink amount data M_ink (tone value for each ink color). In S220, the halftone processing unit M5 extracts the gradation value for each ink color from the ink amount data M_ink of the main image, and binarizes the halftone process by referring to the dither pattern for each ink color. )I do. By the processing of S220, binary data MBD of the main image is created. The color conversion process and the halftone process performed in S220 are the same as the processes in S120 and S135.

  In S225, the combined background image data BID ′ obtained by combining the first background image data BID1 and the second background image data BID2 is generated, and the color conversion unit M4 performs color conversion processing on the combined background image data BID ′ to generate ink. The amount data B_ink is created, and the halftone processing unit M5 performs halftone processing on the created ink amount data B_ink, thereby creating binary data BBD for the composite background image data BID ′. The color conversion process and the halftone process performed in S225 are the same as the process of S140.

  In S230, the print data creation unit M6 prints the main image MI and the background images BI1 and BI2 on the printer 100 based on the binary data MBD of the main image, the binary data BBD of the background image, and the print order designation data POD. Create a control command to The print data creation process in S230 is the same as the process in S145.

  In step S235, the printer driver PDrv transmits the print control data (print order designation command, vertical position designation command, horizontal position designation command, raster command) created in step S230 to the printer 100. This completes the processing by the printer driver PDrv.

(2-3) Third Embodiment of Print Processing:
Next, the printing process when the main image MI is composed of the first main image data MID1 including the two main images MI1 and the second main image data MID2 including the main image MI2 as shown in FIG. 7 will be described. . This printing process is the third embodiment. The printing process according to the third embodiment is a process when a plurality of main image data for printing after overlapping a plurality of main images in layers is input. In the third embodiment, a process for removing the influence of background image data is performed on each of a plurality of main image data, the plurality of main image data are combined, and the background of the combined main image data Performs processing to remove the influence of image data. At this time, the main image data before composition is removed from the influence of the background image data by the method of the first embodiment described above, and the main image data after composition is determined by the background image data by the method of the second embodiment described above. Remove the effect.

FIG. 15 is a flowchart showing the flow of a third embodiment of the printing process executed by the printer driver. The detailed processing of the processing shown in the figure is the same as that of the first embodiment, and detailed description of each step is omitted.
In the process shown in FIG. 15, first, first main image data MID1, second main image data MID2, first background image data BID1, second background image data BID2, and printing order designation data POD are acquired from the application program APL (S300). ), It is determined whether the first background image data BID1 and the second background image data BID2 affect the first main image data MID1 and the second main image data MID2 (S305). If it is determined in S305 that the first background image data BID1 or the second background image data BID2 has an influence on the first main image data MID1 and the second main image data MID2, the process proceeds to S310, and the first main image data If it is determined that at least one of the first background image data BID1 and the second background image data BID2 does not affect the MID1 and the second main image data MID2, the process proceeds to S380.

  In S310, it is determined whether or not each pixel data M1_Pix constituting the first main image data MID1 is transmissive setting, and the pixel data determined to be transmissive setting pixel data M1_Pix is determined (S310: Yes). The gradation value of the pixel data B1_Pix of the first background image data BID1 at the position corresponding to the pixel data M1_Pix is set to 0, and the white density of the pixel data B2_Pix of the second background image data BID2 is 100% white solid. Processing, that is, whitening processing is executed (S315). On the other hand, the non-transparent pixel data among the pixel data M1_Pix constituting the first main image data MID1 is not subjected to whitening processing and proceeds to S320 (No in S310).

  In S320, the color conversion unit M4 creates ink amount data M1_ink of the main image from the first main image data MID1. Then, the influence determination unit M2 determines the influence of the background image on the main image based on the ink amount data M1_ink of the main image (S325), and the first main image data MID1 determined to be influenced by the background image. With respect to the pixel data B1_Pix of the first background image data BID1 at a position corresponding to the pixel data M1_Pix, the process proceeds to S330 to execute the whitening process (S325: Yes), and the first main image data determined not to be affected by the background image For pixel data B1_Pix at a position corresponding to the pixel data M1_Pix of MID1, the process proceeds to S335 without performing whitening processing (S325: No).

In S310 to S355, the same processing as S310 to S330 is performed based on the relationship between the second main image data MID2 and the first background image data BID1.
In S360, the first main image data MID1 and the second main image data MID2 are combined to create combined main image data MID ′. This composition is executed in accordance with the so-called overlay designation in Photoshop or the like.

  Next, with respect to the appearance (color reproduction) of the print result printed by the composite main image data MID ′, the influence determination unit M2 has at least one print result of the first background image data BID1 and the second background image data BID2. It is determined for each pixel data whether or not there is an influence (S365). The influence determination unit M2 determines whether or not the pixel data that is determined to have an influence is the transmission setting (S370), and if it is the transmission setting, the process proceeds to S375 (S370: Yes). In the case of the non-transparent setting, the process proceeds to S385 (S370: No). On the other hand, the pixel data determined to have no influence proceeds to S385 as it is (S365: No).

In S375, the influence removing unit M3 receives the pixel data M′_Pix determined to be affected by the background image by the color color component of the pixel data B1_Pix of the first background image data BID1 at the position corresponding to the pixel data. Change to a color that takes effect into account. The process in S375 is the same as the process in S215 of the second embodiment. When the processes of S365 to S375 are completed for all the pixel data of the synthesized main image data MID ′, S385 is executed.
Note that the subsequent processes of S385 to S400 are the same as the processes of S220 to 235 in the second embodiment.

(3) Printing process on the printer:
When the print control command created and output in each embodiment as described above is input to the printer 100, the printer 100 executes printing based on the print control command.
FIG. 16 is a flowchart of print processing executed by the printer 100. The processing shown in the figure is executed by the command processing unit M11 executed in the control unit of the printer 100.
In step S505, print control data received from the printer driver PDrv of the PC 200 is received.
In S510, the type of the received command is determined, and any one of S515 to S530 is performed according to the type of command. That is, if the received command is a printing order designation command, the process proceeds to S515. If the received command is a horizontal position designation command, the process proceeds to S520. If the received command is a vertical position designation command, the process proceeds to S525. If is a raster command, the process proceeds to S530.

  In S515, the printing order designation data POD designated by the received printing order designation command is stored in the RAM 130. In S520, the horizontal position designated by the received horizontal position designation command is updated as the horizontal print start position X. In step S525, the vertical position designated by the received vertical position designation command is updated as the print start position Y in the vertical direction. In S530, the raster data included in the received raster command is stored in the raster buffer 132 for each ink code.

FIG. 17 is an explanatory diagram showing a detailed configuration of the raster buffer 132 and the head buffer 127. The color image raster buffer 132c is shown in the upper part of the figure, and the background image raster buffer 132w is shown in the middle part of the figure. As shown in the figure, the raster buffer 132 is assigned a region for each ink code. The color image raster buffer 132c is configured as a set of regions corresponding to each color ink code, and the background image raster buffer 132w is also a set of regions corresponding to each background image ink code. It is configured as.
The size in the X direction of each area of the raster buffer 132 corresponds to the image size, and the size in the Y direction is more than half the height of the print head 120.
The raster buffer 132 has a raster buffer pointer in the Y direction that indicates how far raster data has been received.

The lower part of FIG. 17 shows the head buffer 127. As shown in FIG. 17, the head buffer 127 is allocated with areas for seven ink colors. That is, the head buffer 127 includes a cyan area (for C and WC), a magenta area (for M and WM), a yellow area (for Y and WY), and a black area (for K and WK). ) Area, light cyan (lc and Wlc) areas, light magenta (lm and Wlm) areas, and white (W and WW) areas.
The size in the X direction of each area of the head buffer 127 corresponds to the scanning distance of the carriage, and the size in the Y direction corresponds to the number of nozzles constituting the nozzle row 146 of the print head 120. Each region of the head buffer 127 for each ink color is divided into an upstream head buffer 127u and a downstream head buffer 127l.

FIG. 18 is an explanatory diagram illustrating the configuration of the print head 120 of the printer 100. As shown in FIGS. 18A and 18B, the print head 120 is provided with nozzle rows 146 corresponding to the seven ink colors. The nozzle row 146 is formed so as to extend along the Y direction (print medium feeding direction).
Further, as shown in FIG. 18C, each nozzle row 146 is constituted by 32 nozzle groups arranged along the Y direction. In the present embodiment, among the nozzle groups constituting the nozzle row 146, the nozzle group (nozzle 1 to nozzle 16) located in the upstream half in the print medium feed direction is defined as the upstream nozzle group, and the downstream side in the print medium feed direction. Let the nozzle group (nozzle 17-nozzle 32) located in a half be a downstream nozzle group.

  As shown in FIG. 18A, when the background image is first printed on the print medium, the background image is formed using the upstream nozzle group of each nozzle row 146 of the print head 120, and the downstream nozzle group is formed. Is used to form a main image. As shown in FIG. 18B, when the main image is first printed on the print medium, the upstream nozzle group of each nozzle row 146 of the print head 120 is used to form the main image, and the downstream side. A background image is printed using a nozzle group.

  As shown in FIG. 17, the upstream head buffer 127u is a head buffer corresponding to the upstream nozzle group, and the downstream head buffer 127l is a head buffer corresponding to the downstream nozzle group.

  In S535, it is determined whether or not a raster buffer is stored in the raster buffer 132 corresponding to half the height of the print head 120. If not stored, the process proceeds to S580, and the buffer pointer is updated in S580. On the other hand, if it is stored, the process proceeds to S540.

In S540, based on the print order designation data POD stored in the RAM 130, it is determined which of the main image and the background image is to be printed first. If the main image is printed first, the process proceeds to S545. If the background image is printed first, the process proceeds to S550.
In S545, the raster data is transferred from the main image raster buffer 132c to the upstream head buffer 127u, and the raster data is transferred from the background image raster buffer 132w to the downstream head buffer 127l. Accordingly, the main image is formed using the upstream nozzle group of each nozzle row 146 of the print head 120, and the background image is formed using the downstream nozzle group.
In S550, the raster data is transferred from the raster buffer 132c for the main image to the downstream head buffer 127l, and the raster data is transferred from the raster buffer 132w for the background image to the upstream head buffer 127u. Therefore, the background image is formed using the upstream nozzle group of each nozzle row 146 of the print head 120, and the main image is formed using the downstream nozzle group.
Since the upstream nozzle group and the downstream nozzle group have different physical printing positions on the paper, when the raster data is transferred from the raster buffer 132, the corresponding raster data of the upstream nozzle group and the downstream nozzle group is stored. The transfer start data position on the raster buffer is determined with a timing difference corresponding to the difference in print position so that printing is performed at a corresponding position on the paper.

In S555, the print medium feed controller 150 is controlled to transport the print medium PM so that the print start position of the print medium PM and the position of the print head 120 coincide with each other in the sub-scanning direction.
In S560, the carriage controller 135 is controlled to move the print head 120 so that the print start position of the print medium PM matches the position of the print head 120 in the main scanning direction.
In step S565, main scanning is performed and printing for a range corresponding to the length of the print head 120 in the sub-scanning direction is executed. At this time, the image formation by the upstream nozzle group and the image formation by the downstream nozzle group are executed in parallel.

In S570, the raster buffer pointer of the raster buffer 132 is cleared.
In S575, it is determined whether printing of the entire print image PI has been completed. If printing has not been completed, the processes of S505 to S570 are repeatedly executed until it is determined that printing has been completed. If printing has been completed, the printing process in FIG. 16 ends.

(4) Modification:
In each of the above-described embodiments, the case where the transmittance is complete transmission or complete non-transmission has been described as an example. However, there is a possibility that a transmittance other than 0% or 100% is set in the main image data. is there. In such a case, the transmittance is taken into account in the process of correcting the main image data MID of the second embodiment and the synthesized main image data MID ′ of the third embodiment to remove the influence of the background image data. There is a need.

この目的関数を極小化するＬ^＊ _ｘａ^＊ _ｘｂ^＊ _ｘに対応するＣＭＹＫ値は、入力された背景画像データのカラー色成分がＴ％だけ印刷結果の見えに寄与するように印刷されたときに、主画像データの見えが作成者の意図していたい色の見えからのずれが極小化するようになっている。 Therefore, in this modification, the Lab value created from the pixel data of the main image data and the Lab value created from the background image data are reflected in the print result (the color color of the pixel data in the background image data). An objective function weighted according to the degree to which the component should be reflected in the print result is set. For example, when the transmittance set in the pixel data of the main image data is T%, the objective function can be expressed by the following equation (2).

CMYK values corresponding to the objective function _{^{L * x a * x b *}} x that minimizes when the color-component of the input background image data is printed so as to contribute to the appearance of only the printed result T% Furthermore, the deviation of the appearance of the main image data from the appearance of the color desired by the creator is minimized.

When the pixel data of the main image data is corrected using the above equation (2) as the objective function, the Lab value ((T / 100) corresponding to the transmittance of the corresponding pixel data of the first background image data BID1 is also obtained. ) L ^* ₂ , (T / 100) a ^* ₂ ), and (T / 100) b ^* ₂ ) corresponding to CMYK values. Of course, as in the case of the main image data MID, referring to the inverse model LUT, the Lab values ((T / 100) L ^* ₂ , (T / 100) a ^* ₂ ), ( The ink amount data M_ink may be calculated from T / 100) b ^* ₂ ).

(5) Summary:
As described above, according to the printer 100 of each of the embodiments described above, at least based on the image data including the main image data MID for printing the main image and the background image data BID for printing the background image. When printing, the overlapping part of the main image MI and the background image BI when printed on the printing medium is detected, and the background image data BID of the overlapping part is corrected by correcting the background image data BID based on the detection result. Can be corrected. By performing printing based on the background image data BID thus corrected and the main image data MID on the print medium in a predetermined order, the image quality of the print result can be improved.

  Note that the present invention is not limited to the above-described embodiments and modifications, and the configurations disclosed in the above-described embodiments and modifications are mutually replaced, the combinations are changed, the known technology, and the above-described implementations. Configurations in which the configurations disclosed in the embodiments and modifications are replaced with each other or combinations thereof are also included.

DESCRIPTION OF SYMBOLS 100 ... Printer, 105 ... CPU, 110 ... RAM, 115 ... ROM, 120 ... Print head, 125 ... Head controller, 135 ... Carriage controller, 140 ... Carriage motor, 145 ... Print medium feed motor, 150 ... Print medium feed controller, 155 ... USB interface, 200 ... personal computer, 205 ... CPU, 210 ... RAM, 215 ... ROM, 225 ... display interface, 225a ... display, 230 ... operation input device interface, 230a ... operation input device, 235 ... hard disk, 240 ... USB interface, APL ... application program, PDrv ... printer driver, M1 ... image data acquisition unit, M2 ... influence determination unit, M3 ... exclusion M4 ... color conversion unit, M5 ... halftone processing unit, M6 ... print data creation unit, M7 ... forward model converter, M11 ... command processing unit, M71 ... spectral printing model converter, M72 ... color calculation unit, PD ... printing Data, POD ... Print order designation data, MID ... Main image data, MID1 ... First main image data, MID2 ... Second main image data, M_ink ... Main ink amount data, MBD ... Main image binary data, BID ... Background image data, BID1 ... First background image data, BID2 ... Second background image data, B_ink ... Background ink amount data, BBD ... Background image binary data, HTRm ... Main image halftone resource, HTRb ... Background image halftone resource, LUTm ... color conversion table, LUTb ... color conversion table

Claims (8)

A printing apparatus for printing on a printing medium based on image data, wherein the image data includes at least first image data for printing a main image and second image data for printing a background image,
Detecting means for detecting an overlapping portion of the main image and the background image when printed on the print medium;
Image correcting means for correcting the background image of the overlapping portion by correcting the second image data;
Printing means for performing printing of a main image based on the first image data and printing of a background image based on the second image data on the print medium in a predetermined order;
A printing apparatus comprising:   The printing apparatus according to claim 1, wherein the image correcting unit corrects the overlapping portion of the background image to a white image. In the first image data, a color variation allowable value indicating whether or not color variation in the printing result is permitted is set.
The image correcting means corrects the background image of the overlapping portion when the color variation allowable value does not allow the color variation of the main image at the overlapping portion in the first image data. 2. The background image of the overlapping portion is not corrected when color variation of the main image at the overlapping portion is allowed by the color variation allowable value in one image data. The printing apparatus according to 2.   The image correcting means corrects the background image of the overlapping portion when the main image of the overlapping portion is a specific color set in advance so as not to allow color variation in the printing result. The printing apparatus according to any one of claims 1 to 3.   The image correcting means corrects the overlapping portion of the background image when there is a color color component at the overlapping portion of the background image and a color color component at the overlapping portion of the main image, and the background image When there is no color color component at the overlapping part of the background image without correcting the overlapping part of the background image when there is no color color component at the overlapping part of the main image The printing apparatus according to claim 1, wherein the overlapping portion of the background image is not corrected.   The said image correction means corrects the said background image of the site | part corresponding to the site | part corresponding to the ink recording rate of the said 1st image data exceeding a predetermined ratio, The said any one of Claim 1-5 characterized by the above-mentioned. The printing apparatus as described. A printing program for causing a computer to realize a function of printing on a printing medium based on image data, wherein the image data includes at least first image data for printing a main image and a first image for printing a background image. Consisting of two image data,
A detection function for detecting overlapping portions of the main image and the background image when printed on the print medium;
An image correction function for correcting the background image of the overlapping portion by correcting the second image data;
A printing function for performing, in a predetermined order, printing of a main image based on the first image data and printing of a background image based on the second image data on the print medium;
A printing program characterized in that a computer is realized. When image data is composed of at least first image data for printing a main image and second image data for printing a background image, a printing method for printing on a print medium based on these image data,
A detection step of detecting an overlapping portion of the main image and the background image when printed on the print medium;
An image correction step of correcting the background image at the overlapping portion by correcting the second image data;
A printing step of performing printing of a main image based on the first image data and printing of a background image based on the second image data on the print medium in a predetermined order;
A printing method comprising:

Images