JP2012196813A - Printer, printing control method and printing control program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve both the solution of the nonuniform ink consumption and a maintenance of image quality, as certain ink among the plurality of ink in similar color is nonuniformly consumed in a printer usable a plurality of ink in similar color.SOLUTION: In the printer usable the first ink and the second ink in similar color and having different properties in printing, when a specific mode for saving the first ink is designated and received as a printing mode, the first ink and the second ink are used for printing in accordance with a ratio of the first ink to the second ink, that is, the ratio for achieving the color development where a color development difference in printing from the color development using the first ink out of both ink is within a prescribed allowable range.

Description

  The present invention relates to a printing apparatus, a printing control method, and a printing control program.

  There are products that can use a plurality of inks having the same color and different characteristics as printing apparatuses. As the plurality of inks having the same color and different characteristics, a black ink (referred to as a matte black ink or MK ink) and a glossy paper system that realizes good color development when attached to a mat paper medium. This corresponds to a black ink (referred to as a photo black ink or PK ink) that realizes good color development when adhered to the medium. As such a printing apparatus, an apparatus that prints using MK ink and PK ink in a predetermined range in a black gradation value when coloring mat paper using MK ink and PK ink is known. (See Patent Document 1).

  Further, there is known a printing apparatus that performs printing using a plurality of printing materials, and performs control so as to reduce the consumption of at least one printing material in accordance with the remaining amounts of the plurality of printing materials. (See Patent Document 2).

JP 2010-36479 A JP 2004-93817 A

  In a printing apparatus equipped with a plurality of inks of the same color system as described above, some of the plurality of inks of the same color system are more than other inks while repeating arbitrary printing processing by the user. May be consumed in large quantities. Such biased consumption (referred to as biased reduction) for some inks forces the user to frequently replace ink cartridges for some inks, which may affect the efficiency of the printing process. It can be an impediment to user comfort. In addition, the said literature 1 was not going to contribute to prevention of the above-mentioned uneven reduction. Moreover, although the said literature 2 reduces the consumption of a part of printing material, since it does not accompany image quality compensation with respect to the consumption reduction of this printing material, it causes the fall of the quality of a printing result.

  The present invention has been made in order to solve the above-mentioned problems, and by preventing unevenness of some of the inks, the efficiency of the printing process is improved and the complexity of the user is reduced. Provided are a printing apparatus, a printing control method, and a printing control program capable of preventing a decrease.

  One aspect of the present invention is a printing apparatus that can use a first ink and a second ink, which are inks of the same color and have different characteristics, for printing, and a specification for saving the first ink as a printing mode. When the mode designation is received, the color ratio is the ratio between the first ink and the second ink, and the color difference between the two inks and the color developed by printing using the first ink falls within a predetermined allowable range. According to the realized ratio, the first ink and the second ink are used for printing.

  According to the present invention, when designation of the specific mode is accepted, the first ink and the second ink are in accordance with a ratio that realizes color development so that the difference from color development by printing using the first ink is within a predetermined allowable range. Ink is used for printing. Therefore, it is possible to prevent the first ink from being unevenly reduced, and it is possible to prevent the quality of the printing result from being deteriorated while supplementing the amount of consumption of the first ink with the second ink.

As one aspect of the present invention, the printing apparatus performs color conversion in which a plurality of input grid points represented in a predetermined input color system are associated with ink amounts for each ink type used for printing. A normal color conversion table in which only the ink amount of the first ink is registered as the ink amount for the color corresponding to the first ink and the second ink, and the normal color conversion table as the ink amount for the color A storage unit storing a rewritten color conversion table in which the ink amounts of the registered first ink are allocated to the first ink and the second ink at the above ratio, and the specific mode is specified Is received, the image data representing the image to be printed in the input color system is color-converted using the rewrite color conversion table, and designation of a print mode other than the specific mode is accepted. In this case, the image data to color conversion using the normal color conversion table may be executing printing based on ink amount data generated by the color conversion.
According to this configuration, when the specification of the specific mode is accepted, the rewrite color conversion table is used for color conversion, so that the difference from color development by printing using only the first ink is within a predetermined allowable range. The first ink and the second ink are used for printing in accordance with a ratio that realizes color development that falls within the range.

As one aspect of the present invention, the storage unit generates a plurality of inks generated by differentiating the ratio when distributing the ink amount of the first ink to the ink amount of the first ink and the ink amount of the second ink. If a rewritten color conversion table is stored and designation of the specific mode is accepted, a color conversion table used for color conversion may be selected from a plurality of rewritten color conversion tables in accordance with an instruction from the outside. Good.
According to this configuration, the user realizes color development that falls within the above-described allowable range, and realizes a rewritten color conversion table that is more effective in eliminating unevenness of the first ink (saving of the first ink) and higher image quality. The rewritten color conversion table to be selected can be arbitrarily selected.

As one aspect of the present invention, a printing apparatus includes a display control unit that displays a user interface screen for selecting a color conversion table used for color conversion from a plurality of rewritten color conversion tables on a predetermined display unit. The display control unit includes, in the user interface screen, a color conversion table that achieves a relatively high saving effect of the first ink among a plurality of rewritten color conversion tables or a color conversion table that realizes a relatively high image quality. Any one of them may be displayed as a recommended color conversion table in a specific display mode.
According to this configuration, the user can easily select a desired rewrite color conversion table via the user interface screen. In addition, since either the rewritten color conversion table with higher saving effect of the first ink or the rewritten color conversion table realizing higher image quality is displayed as the recommended color conversion table, such a recommended color conversion table is selected. Cheap.

As one aspect of the present invention, the first ink is an ink that adheres to the first medium and produces a predetermined color, and the second ink adheres to a second medium different from the first medium and produces a predetermined color. The printing apparatus may be able to designate the specific mode on condition that the designation of the first medium is received as a medium used for printing.
According to this configuration, it is possible to prevent a partial decrease in the first ink that is normally used for printing on the first medium.

As one aspect of the present invention, the specific mode may be specified on condition that the remaining amount of the second ink is larger than the remaining amount of the first ink in the printing apparatus.
According to the configuration, when the first ink is actually deviated, the decrement can be solved accurately.

  The printing apparatus according to the present invention may be realized by a single apparatus (printer) or may be realized as a system including a plurality of apparatuses (such as a PC that controls the printer and the printer). The technical idea of the present invention can be realized by means other than the invention of the product. For example, the invention of a method (printing control method) including processing steps executed by the above-described printing apparatus and a program (printing control program) for realizing such processing steps in a printing apparatus or other hardware (such as a PC) It is possible to grasp.

It is a figure which shows roughly the apparatus structure of this embodiment. 6 is a flowchart illustrating print control processing according to the first exemplary embodiment. It is a flowchart which shows the outline of the acquisition process of rewriting color conversion LUT. It is a figure which illustrates a mode that the normal color conversion LUT is rewritten. It is a figure which illustrates a mode that 1st ink is distributed to 1st ink and 2nd ink. It is a figure which illustrates the color development characteristic of each test pattern. 10 is a flowchart illustrating print control processing according to the second exemplary embodiment. It is a figure which shows an example of UI screen for selection. 10 is a flowchart illustrating print control processing according to a third exemplary embodiment. It is a figure which shows the other example of UI screen for selection. It is a figure which shows the other example of UI screen for selection. It is a figure which illustrates the color development characteristic of the 1st ink and the 2nd ink. It is a flowchart concerning the change process of a ratio. It is a figure which illustrates UI screen.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1. Outline of Apparatus FIG. 1 schematically shows an apparatus configuration according to the present embodiment. FIG. 1 shows a computer 10 as a PC and a printer 50. The computer 10 and / or the printer 50 are the execution subject of the print control method. In the computer 10, the CPU 11 controls the printer 50 by expanding the program data 21 stored in the hard disk drive (HDD) 20 or the like to the RAM 12 and performing calculations according to the program data 21 under the OS. The printer driver 13 is executed. The printer driver 13 has functions such as an image data acquisition unit 13a, a color conversion processing unit 13b, a halftone (HT) processing unit 13c, a rasterization processing unit 13d, a user interface (UI) control unit 13e, and an LUT setting unit 13f. It is a program for making it run. Each of these functions will be described later.

  A display 30 as a display unit is connected to the computer 10, and the UI control unit 13e displays a UI screen necessary for each process on the display 30. Further, an operation unit 40 such as a keyboard and a mouse is connected to the computer 10, and an instruction necessary for each process is input by the user via the operation unit 40. A printer 50 is connected to the computer 10. As will be described later (FIG. 2 and the like), in the computer 10, drive data is generated based on an image file representing an image to be printed by the function of the printer driver 13, and the drive data is transmitted to the printer 50. The

In the printer 50, the CPU 51 expands the program data 54 stored in the memory such as the ROM 53 into the RAM 52 and performs a calculation according to the program data 54 under the OS, thereby controlling the firmware FW for controlling the device itself. Is executed. The firmware FW can execute printing based on the drive data by sending the drive data transmitted from the computer 10 to the ASIC 56.
The firmware FW acquires an image file representing an image to be printed from a memory card attached to an external connection connector (not shown), an external device (for example, the computer 10), and the like, and is driven based on the acquired image file. Data can also be generated. In this way, even when drive data is generated by the function of the firmware FW, the drive data is sent to the ASIC 56.

  The ASIC 56 acquires drive data and generates a drive signal for driving the paper feed mechanism 57, the carriage motor 58, and the print head 62 based on the drive data. The printer 50 includes a carriage 60, and the carriage 60 is loaded with ink cartridges 61 for each of a plurality of types of ink. The printer 50 includes a plurality of inks including a plurality of inks having at least the same color and different characteristics. In the example of FIG. 1, ink cartridges 61a, 61b, 61c, 61d, and 61e corresponding to various inks of cyan (C), magenta (M), yellow (Y), matte black (MK), and photo black (PK) are provided. It is installed. The carriage 60 includes a print head 62 that ejects ink supplied from each ink cartridge 61 from a number of nozzles. The specific types and number of inks installed in the printer 50 are not limited to those described above. For example, light cyan (LC), light magenta (LM), orange (OR), green (G), gray (LK), light Various inks such as gray (LLK) can be mounted. The ink cartridge 61 may be installed at a predetermined position in the printer 50 without being mounted on the carriage 60.

The paper feed mechanism 57 is driven and controlled by the ASIC 56 to carry the print medium and feed the paper. Further, the carriage 60 is moved in the main scanning direction of printing (main scanning) by controlling the driving of the carriage motor 58 by the ASIC 56, and the ASIC 56 moves each nozzle to the print head 62 at a predetermined timing along with the main scanning. Ink is ejected from the ink. As a result, ink droplets (dots) adhere to the print medium, and an image (print target image) corresponding to the drive data is reproduced on the print medium. The printer 50 further includes an operation panel 59. The operation panel 59 includes a display unit (for example, a liquid crystal panel), a touch panel formed in the display unit, various buttons and keys, and accepts input from the user and displays a necessary UI screen on the display unit. .
On the premise of such a device configuration, a plurality of embodiments will be described below.

2. Example 1:
FIG. 2 is a flowchart illustrating print control processing according to the first embodiment. Here, description will be made assuming that the CPU 11 executes the flowchart by the printer driver 13 (printing control program). Assuming that the flowchart is started, it is assumed that the printer driver 13 accepts selection of an arbitrary print target image by the user via the operation unit 40.

  In step S100, the CPU 11 determines whether the type of medium used for printing is a specific medium (hereinafter referred to as a first medium). The type of medium used for printing can be arbitrarily designated via the UI screen displayed on the display 30 by the user operating the operation unit 40. Therefore, the CPU 11 determines whether or not the medium designated by the user via the UI screen (hereinafter referred to as a designated medium) is the first medium. If the medium is the first medium, the CPU 11 proceeds to step S110.

  The printer driver 13 executes color conversion processing for converting the color system of the image in the process of generating drive data based on the image file representing the print target image (step S140 described later). For color conversion processing, a color conversion lookup table (color conversion LUT) that defines the correspondence between an input color system (for example, RGB color system) and an output color system (ink amount space) for a plurality of input grid points. Is used. In this embodiment, a plurality of color conversion LUTs 22 corresponding to the types of print media that can be used in the printer 50 are stored in the HDD 20 in advance, and basically the color conversion LUTs 22 corresponding to the types of designated media are used. The color conversion process is executed. Accordingly, when a mat paper type medium is selected as the designated medium, basically, the color conversion LUT 22 corresponding to the mat paper type is used. On the other hand, when a glossy paper type medium is selected as the designated medium, basically, the color conversion LUT 22 corresponding to the glossy paper type is used. In the color conversion LUT 22 corresponding to the mat paper system, ink amounts (tone values) for C, M, Y, and MK inks are defined as output values associated with the input grid points. That is, when a mat paper medium is selected, MK ink is used for printing as black ink. On the other hand, in the color conversion LUT 22 corresponding to glossy paper, ink amounts (tone values) for C, M, Y, and PK inks are defined as output values associated with the input grid points. Yes. That is, when a glossy paper medium is selected, PK ink is used for printing as black ink.

  Here, as the user repeats the printing process arbitrarily using the printer 50, if the consumption speeds of the various inks mounted on the printer 50 are approximately the same, from the viewpoint of printing efficiency and avoiding bothering the user. Ideally, some ink consumption may be significantly higher than other inks. As an example of such partial reduction of ink, there is a situation in which MK ink is consumed in a large amount compared to PK ink. Therefore, in the flowchart, as an example, processing for suppressing the uneven decrease in MK ink is executed as necessary. Further, in this embodiment, not only the decrease in MK ink is suppressed, but also the image quality of the print result is ensured (the print result in the case where the decrease is not performed and the case where the decrease is not performed). Is almost the same). In the following description, it is assumed that the first medium is a mat paper medium unless otherwise specified. In addition, when the first medium is a mat paper medium, the first ink is MK ink and the second ink is PK ink.

  In step S110, the CPU 11 determines whether or not the designation of a specific mode (MK ink saving mode) for saving the first ink as the printing mode has been received. The print mode can be arbitrarily designated via the UI screen displayed on the display 30 by the user operating the operation unit 40. In addition, the UI control unit 13e enables (displays) the “MK ink saving mode” as a selection only when the first medium (mat paper medium) is selected as the designated medium on the UI screen. Therefore, the user can select the “MK ink saving mode” only when a mat paper medium is designated on the UI screen. If the specific mode is designated as the print mode (“Yes” in step S110), the CPU 11 proceeds to step S120; otherwise (if a designation of a print mode other than the specific mode is accepted). In S110, “No”), the process proceeds to step S130.

  In step S120, the LUT setting unit 13f sets the color conversion LUT 22 ′ stored in the HDD 20 corresponding to the designated medium (first medium) as the color conversion LUT used for the color conversion process. The color conversion LUT 22 ′ is a color conversion LUT generated by rewriting the output value defined by the color conversion LUT 22. Like the color conversion LUT 22, the color conversion LUT 22 ′ is stored in advance in the HDD 20 in a state associated with the type of medium. Has been. The color conversion LUT 22 ′ set here is registered in the color conversion LUT 22 corresponding to the designated medium (first medium) as the ink amount for the color (black in this embodiment) corresponding to the first ink and the second ink. This corresponds to a rewritten color conversion table in which the ink amounts obtained by distributing the ink amounts of the first ink into the first ink and the second ink at a certain ratio are registered. The color conversion LUT 22 ′ is also referred to as a rewritten color conversion LUT 22 ′ as appropriate.

  On the other hand, in step S130, the LUT setting unit 13f sets the color conversion LUT 22 stored in the HDD 20 corresponding to the designated medium (first medium) as the color conversion LUT used for the color conversion process. The color conversion LUT 22 set here corresponds to a normal color conversion table in which only the ink amount of the first ink is registered as the ink amount for the color corresponding to the first ink and the second ink (black in this embodiment). The color conversion LUT 22 is also referred to as a normal color conversion LUT 22 as appropriate. That is, when the user does not designate the specific mode (“No” in step S110), since the necessity of using the second ink when printing on the designated medium is low (no), the normal color conversion LUT 22 is set. use. The HDD 20 corresponds to a storage unit.

Here, before describing the processing in step S140 and subsequent steps, a method for obtaining the rewritten color conversion LUT 22 ′ corresponding to the first medium will be described.
FIG. 3 is a flowchart showing an outline of acquisition processing of the rewrite color conversion LUT 22 ′ corresponding to the first medium. This process is realized by a computer (for example, the computer 10) executing a process according to a predetermined LUT generation program. In step S200, a normal color conversion LUT 22 corresponding to the first medium is prepared. In this case, the computer may generate the color conversion LUT 22 for the first medium by a known method, or the color conversion LUT 22 for the first medium that has already been generated may be read from the outside.

  In step S210, the computer prints the test pattern on the first medium by a printer (for example, the printer 50) based on the test pattern image data representing a predetermined test pattern. The printer that prints the test pattern is assumed to be the same product as the printer 50, and the first ink and the second ink can be used. The test pattern image data here is, for example, bitmap data (RGB data) in which each pixel constituting the image has gradation values (0 to 255) for each of R, G, and B, and white (R = G = B = 255) to black (R = G = B = 0) represents data representing a gray scale image whose density gradually changes. In step S210, the computer performs color conversion processing on the test pattern image data using the normal color conversion LUT 22 prepared in step S200. At the time of color conversion, an interpolation calculation or the like is executed as necessary. By executing a color conversion process using the normal color conversion LUT 22, the RGB data is converted into ink amount data (CMYMK data) having gradation values for C, M, Y, and MK for each pixel.

  Further, in step S210, a halftone process is executed on the color-converted ink amount data to thereby define a binary halftone that defines either dot formation or non-formation for each ink type and each pixel. Data is generated, and further, drive data is generated by assigning information for each ink type and pixel of the halftone data to each main scan and each ink nozzle of the printer print head (rasterization processing), and the drive data is sent to the printer. Output. As a result, the test pattern is printed on the first medium by the printer. The second ink (PK ink) is not used at all for the test pattern printed in step S210. The test pattern printed in step S210 is called a reference test pattern.

  Next, in step S220, the computer rewrites the output value of the normal color conversion LUT 22 prepared in step S200, thereby generating an LUT (candidate LUT) that is a candidate for the rewritten color conversion LUT 22 ′ corresponding to the first medium. To do. Specifically, the ink amount of the first ink and the ink amount of the second ink according to a certain ratio with respect to the ink amount of the first ink out of the ink amount for each ink type defined as the output value by the normal color conversion LUT 22 And sort. The ratio here may be one of a plurality of predetermined ratios or may be a value designated by a computer operator.

  FIG. 4 illustrates a state in which the normal color conversion LUT 22 is rewritten in step S220. The normal color conversion LUT 22 shown in FIG. 4 is a color conversion LUT 22 corresponding to the first medium (mat paper-based medium), and ink is applied to a plurality of input grid points (R, G, and B gradation values). The amount (C, M, Y, MK gradation values) is uniquely defined. The gradation value as the ink amount is expressed by, for example, 256 gradations (8 bits) from 0 to 255.

  FIG. 5 shows the ink amount of the first ink (MK ink) defined in the normal color conversion LUT 22 corresponding to the first medium (mat paper type medium), and the ink amount of the first ink and the first ink in accordance with the ratio. An example of distribution to the ink amount of two inks (PK ink) is illustrated. In FIG. 5, the ink amount represented by the gradation value of 0 to 255 is shown in a state normalized to a density of 0 to 100% for convenience of explanation (gradation value 255 = density 100%). Of course, the density (%) shown here can be expressed as a gradation value by multiplying it by 255. As illustrated in FIG. 5, when the ratio (first ink: second ink) = 9: 1, the ink amount of the first ink that is defined as the density of 100% in the normal color conversion LUT 22 is the first ink amount. The ink amount of the first ink, which is divided into a density of 90% as the ink amount of the ink and a density of 10% as the ink amount of the second ink, and is defined as the density of 20% in the normal color conversion LUT22, is the first ink amount. The ink is divided into a density of 18% as the ink amount of one ink and a density of 2% as the ink amount of the second ink.

  Similarly, when the ratio is 8: 2, 2/10 of the ink amount of the first ink defined in the normal color conversion LUT 22 is replaced with the ink amount of the second ink. Similarly, when the ratio is 7: 3, 3/10 of the ink amount of the first ink defined in the normal color conversion LUT 22 is replaced with the ink amount of the second ink. In this way, the first ink that has been registered up to that time is obtained by replacing the ink amount of the first ink remaining by replacing the ink amount of the first ink with the ink amount of the second ink and the ink amount of the obtained second ink. The normal color conversion LUT 22 is rewritten as a candidate LUT by registering it as the output value of the normal color conversion LUT 22 instead of the ink amount (see the area surrounded by the chain line in FIG. 4).

  In step S230, the computer causes the printer to print a test pattern on the first medium based on the test pattern image data. However, in step S230, the computer performs color conversion processing on the test pattern image data using the candidate LUT generated in step S220. By executing the color conversion process using the candidate LUT, the test pattern image data is converted into ink amount data (CMYMKPK data) having gradation values for each of C, M, Y, MK, and PK for each pixel. . That is, the first ink and the second ink are used for the test pattern printed in step S230. The test pattern printed in step S230 is called a comparison test pattern.

  The computer repeats the processes of steps S220 and S230 a plurality of times while changing the ratio. The number of repetitions may be a number corresponding to the number of ratios defined in advance, or may be the number specified by the operator of the computer. By repeating the processes of steps S220 and S230 a plurality of times while changing the ratio, printing is performed through the color conversion process by each of the plurality of candidate LUTs having different ratios when the first ink and the second ink are distributed. A plurality of comparative test patterns can be obtained. That is, the ratio and the candidate LUT are in one-to-one correspondence, and the candidate LUT and the comparison test pattern are in one-to-one correspondence.

  In step S240, the computer selects an optimal candidate LUT based on the reference test pattern and the plurality of comparison test patterns, and determines the selected candidate LUT as the rewritten color conversion LUT 22 ′ corresponding to the first medium. The optimal candidate LUT here is, for example, the ratio of both inks when the first ink and the second ink are used together by printing using only the first ink of the first ink and the second ink. This is a ratio that realizes color development in which the difference from color development falls within a predetermined allowable range, and means a candidate LUT in which the ratio of the second ink is as high as possible. Such determination of the color conversion LUT 22 ′ may be automated by a computer or may be made based on a visual inspection by an operator. In the former case, the computer measures the reference test pattern and each comparison test pattern printed on the first medium using a predetermined colorimetric device, and inputs each colorimetric result.

  FIG. 6 illustrates the color development characteristics obtained according to the color measurement results of the reference test pattern and each comparison test pattern. As an example, the characteristic (solid line) for the reference test pattern PT0, the characteristic (two-dot chain line) for the comparative test pattern PT1 corresponding to the candidate LUT with the ratio = 9: 1, and the ratio = 8: 2. The characteristic (two-dot chain line) for the comparison test pattern PT2 corresponding to the candidate LUT and the characteristic (two-dot chain line) for the comparison test pattern PT3 corresponding to the candidate LUT having the ratio = 7: 3 are shown. In FIG. 6, test pattern image data for gray scale is shown on the horizontal axis (image data showing white is shown as 0% density and image data showing black is shown as 100% density), and the vertical axis is brightness as a colorimetric result. L * is marked. Since the PK ink as the second ink has a characteristic that it is thinner than the MK as the first ink, the test pattern having a higher ratio of the second ink has a generally brighter characteristic.

  The computer determines a predetermined density in the test pattern image data, for example, the lightness L * of the reference test pattern PT0 corresponding to the maximum point on the horizontal axis, and the lightness L * of each of the comparison test patterns PT1 to PT3 corresponding to the point. Each difference is calculated. Of the candidate LUTs corresponding to the comparison test patterns in which the brightness difference is within a predetermined range (allowable range), the candidate LUT having the highest ratio of the second ink in the above ratio is referred to as a rewritten color conversion LUT 22 ′. To do. Here, the lightness difference allowable range is a value determined in advance as a range in which the difference cannot be recognized by human eyes.

  If, among the plurality of comparison test patterns, the three comparison test patterns PT1 to PT3 shown in FIG. 6 all have a lightness difference from the reference test pattern TP0, a candidate corresponding to the comparison test pattern PT3. The ratio of the second ink is the highest when the LUT is generated. Therefore, the candidate LUT corresponding to the comparison test pattern PT3 is the rewritten color conversion LUT 22 ′ for the first medium. On the other hand, when based on the visual inspection by the operator, for example, the visual evaluation of whether or not the lightness difference between the reference test pattern as described above and each comparison test pattern is the allowable range, and the allowable range and the evaluation. The operator selects one candidate LUT from the candidate LUTs corresponding to the compared test pattern. Then, input of the selection result of the candidate LUT (for example, input of an identification number written in the comparison test pattern) is performed on the computer. As a result, the computer determines the selected candidate LUT as the rewritten color conversion LUT 22 ′ for the first medium. The rewritten color conversion LUT 22 ′ is stored in the HDD 20 of the computer 10 together with the program data 21 and the normal color conversion LUT 22.

Returning to FIG. 2, the description will be continued.
In step S140, the image data acquisition unit 13a acquires an image file representing an image to be printed from a predetermined storage area such as a memory card attached to the HDD 20 or a connector for external connection (not shown). Here, it is assumed that the image file is bitmap data (RGB data) in which each pixel constituting the image has a gradation value for each of R, G, and B. When the image file is a file described in another format such as PDL, the image data acquisition unit 13a analyzes the file and develops it into bitmap data (RGB data). Furthermore, the image data acquisition unit 13a can appropriately execute a pixel number conversion process or the like for matching the print resolution in the printer 50 to the RGB data.

  In step S150, the color conversion processing unit 13b performs color conversion on the RGB data acquired by the image data acquisition unit 13a using the color conversion LUT set in either step S120 or step S130. When the color conversion process is executed using the color conversion LUT 22 ′ set in step S120, the RGB data has ink amount data (C, M, Y, MK, PK gradation values for each pixel). CMYMKPK data). On the other hand, when the color conversion process is executed using the color conversion LUT 22 set in step S130, the RGB data includes ink amount data (CMYMK) having gradation values for C, M, Y, and MK for each pixel. Data).

  In step S160, the HT processing unit 13c performs halftone processing on the ink amount data converted by the color conversion processing unit 13b, thereby forming either dot formation or non-formation for each ink type and each pixel. Binary halftone data defining one is generated. Halftone processing is executed by a dither method, an error diffusion method, or the like. Note that the halftone data is not limited to binary values. For example, the halftone data is a four-value data that defines either large dot formation / medium dot formation / small dot formation / non-formation for each ink type and each pixel. It may be data. Large dots, medium dots, and small dots are designations for a plurality of dot types that have relatively different ink amounts per tod that can be ejected by the print head 62. The magnitude relationship of the ink amount per dot is large dot> medium dot> small dot.

  In step S170, the rasterization processing unit 13d generates drive data in which information for each ink type and each pixel of the halftone data is assigned to each main scan and each ink nozzle of the print head 62 (rasterization processing), and the drive data is generated. Output to the printer 50. The drive data is accompanied by information necessary for the printer 50 to execute the printing process, such as printing resolution and the number of prints, as well as information on the designated medium, and is transmitted. As a result, the printer 50 executes printing on the designated medium based on the transmitted drive data. In the above example, when the color conversion LUT 22 ′ is set (step S 120), the printer 50 sets the dots of C, M, Y, MK, and PK inks according to the drive data. (Paper-based medium). On the other hand, when the color conversion LUT 22 is set (step S130), the printer 50 ejects C, M, Y, and MK ink dots onto the designated medium (matte paper-based medium) according to the drive data. .

  As described above, according to this embodiment, the first ink is normally used when the printing process is performed using the printer 50 that can use the first ink and the second ink having the same color and different characteristics. When the medium (first medium) is the designated medium and a specific mode for saving the first ink is designated, color development by printing using the first ink of the first ink and the second ink The first ink and the second ink according to the ratio of the first ink and the second ink (the color conversion LUT 22 ′ that realizes such a ratio) that realizes color development to such an extent that the difference between the first ink and the second ink is not perceived. Ink is used for printing. For this reason, it is possible to suppress a partial decrease in some of the plurality of inks of the same color (first ink), and as a result, the efficiency of the printing process and the comfort of the user are improved. In addition, since the amount of the first ink is reduced and compensated by the use of the second ink to such an extent that the color difference from the case where the second ink is not used cannot be recognized, it is possible to surely eliminate the deterioration in the image quality of the printing result. .

  In the flowchart of FIG. 2, the processing when the designated medium is determined to be a medium other than the first medium in step S100 (“No” in step S100) is not particularly described. Print control processing is performed. That is, the CPU 11 (printer driver 13) uses the color conversion LUT 22 stored in the HDD 20 corresponding to the designated medium to perform color conversion on the RGB data representing the print target image, and converts it into ink amount data after color conversion. Based on this, halftone processing and rasterization processing as described above are executed to generate drive data, and the generated drive data is transmitted to the printer 50.

  In the above description, the case where the computer 10 executes the print control process has been described as an example. However, the print control process (including embodiments described later) may be performed in the printer 50. That is, when the CPU 51 of the printer 50 executes the firmware FW (print control program), the image data acquisition unit 13a, the color conversion processing unit 13b, the HT processing unit 13c, the rasterization processing unit 13d, the UI control unit 13e, and the LUT setting unit. Each function such as 13f may be realized in the printer 50, and the flowchart of FIG. In this case, a color conversion LUT 55 (corresponding to a normal color conversion table) and a color conversion LUT 55 ′ (corresponding to a rewritten color conversion table) corresponding to each medium type are stored in advance in the ROM 53 in the printer 50. Is used for color conversion processing. In addition, the CPU 51 receives various kinds of information and instructions such as a print instruction for an image to be printed (image file), a medium used for printing, and a print mode, from the user via the operation panel 59. As a result, drive data is generated by the function of the firmware FW as described above. Alternatively, the flowchart of FIG. 2 may be realized by sharing the printer driver 13 and the firmware FW.

3. Example 2:
In the first embodiment, there is one rewrite color conversion LUT 22 ′ stored in the storage unit (HDD 20) for one medium type, but a plurality of rewrite colors having different ratios for one medium type. Conversion LUT22 'may be memorize | stored. For example, in step S240 (FIG. 3), candidate LUTs corresponding to comparison test patterns whose brightness differences from the reference test pattern as described above are within an allowable range are all determined as the rewrite color conversion LUT 22 ′ for the first medium. And stored in the storage unit (HDD 20). The plurality of rewrite color conversion LUTs 22 ′ relating to the same medium distribute the ratio of the first ink of the normal color conversion LUT22 to the ink amount of the first ink and the second ink when they are generated. And stored in the storage unit.

  FIG. 7 is a flowchart illustrating print control processing according to the second embodiment. In FIG. 7, the same processes as those in the flowchart of FIG. Here, a different part from Example 1 is demonstrated. In step S112, the UI control unit 13e causes the display unit to display a UI screen for selecting a desired LUT from the plurality of rewrite color conversion LUTs 22 ′. The UI control unit 13e corresponds to a display control unit.

  FIG. 8 illustrates the selection UI screen 30a displayed in step S112. In the selection UI screen 30a, for example, a plurality of rewrite color conversion LUTs 22 ′ generated for the first medium (mat paper type medium) are described, and corresponding to each of these descriptions. A check box CB is provided. In the example of FIG. 8, easy-to-understand descriptions such as “image quality priority”, “balance priority”, “MK saving priority”, and the like, and these descriptions and check boxes CB are rewritten color conversion LUT 22 ′. Is uniquely addressed. Further, in the vicinity of these descriptions, the ratio for the rewritten color conversion LUT 22 ′ to which these descriptions correspond is displayed as, for example, “PK replacement rate 10%” or the like (that is, the ratio (first ink: Second ink) = 9: 1).

  In step S114, the LUT setting unit 13f receives selection of the rewrite color conversion LUT 22 ′. The user can arbitrarily select any one of the check boxes CB in the selection UI screen 30a by operating the operation unit 40. The user can confirm the selection of the check box CB at that time by operating the determination button DB in the selection UI screen 30a via the operation unit 40. For this reason, when the determination button DB in the selection UI screen 30a is operated via the operation unit 40, the LUT setting unit 13f rewrites the check box CB checked at that time. Selection of the color conversion LUT 22 ′ is accepted.

  In step S116, the LUT setting unit 13f sets the rewritten color conversion LUT 22 ′ selected in step S114 as a color conversion LUT used for color conversion processing. As described above, according to the second embodiment, a plurality of rewrite color conversion LUTs 22 ′ having different ratios for one medium type are prepared, and the user can arbitrarily select a desired LUT via the selection UI screen 30a. In other words, when it is important to suppress the first ink uneven reduction, the LUT with the highest replacement ratio from the first ink to the second ink can be selected from the prepared rewrite color conversion LUT 22 ′. In addition, even when the second ink is used, if it is desired to minimize the image quality fluctuation, the LUT having the lowest replacement ratio from the first ink to the second ink is selected from the prepared rewrite color conversion LUT 22 ′. can do. Alternatively, when it is desired to obtain an effect by balancing both the suppression of unevenness of the first ink and the image quality, the replacement ratio from the first ink to the second ink is medium in the prepared rewrite color conversion LUT 22 ′. About LUT can be selected.

4). Example 3:
FIG. 9 is a flowchart illustrating print control processing according to the third embodiment. In FIG. 9, the same processes as those in the flowcharts of FIGS. 2 and 7 are denoted by the same reference numerals. Here, a different part from Example 1, 2 is demonstrated. In the third embodiment as well, as in the second embodiment, a plurality of rewrite color conversion LUTs 22 ′ for the first medium are stored in the storage unit in association with the above ratios when they are generated.

  In step S102, the CPU 11 determines whether or not the remaining amount of the second ink in the printer 50 is greater than the remaining amount of the first ink. In this case, the CPU 11 transmits a command (remaining amount request command) for requesting information indicating the remaining amount of the first ink and the remaining amount of the second ink to the printer 50, and the printer 50 side receives the command. In response, information indicating the remaining amount of the first ink and the remaining amount of the second ink (directly or indirectly) is transmitted to the computer 10 side. The printer 50 can grasp the remaining amount of ink in each ink cartridge 61 by various methods including known methods.

  In the present embodiment, the firmware FW uses a dot count function that counts the number of dots that form an image represented by drive data corresponding to one print job for each ink type, and ink according to the number of dots counted by the dot count function. It has a consumption estimation function for estimating ink consumption by type. In the consumption estimation function, a value obtained by multiplying the number of dots counted for each ink type by the amount of ink per dot is stored in a consumption memory (not shown) provided in the ink cartridge 61 corresponding to the ink type. The "current ink consumption" is updated by adding to the "current ink consumption" (see, for example, Japanese Patent Application Laid-Open No. 2007-223060). Further, when the firmware FW receives a remaining amount request command for a certain ink type, the firmware FW starts from an initial ink amount predetermined for that ink type (the amount of ink filled in an unused ink cartridge). By subtracting the “current ink consumption” stored at that time in the consumption memory of the ink type, the current remaining ink amount for the ink type can be calculated. In this way, the firmware FW calculates the remaining amount of the first ink and the remaining amount of the second ink in response to the remaining amount request command, and transmits information indicating the calculated remaining amount to the computer 10 side.

  Accordingly, in step S102, based on the information acquired from the printer 50 as described above, it is determined whether or not the remaining amount of the second ink is larger than the remaining amount of the first ink. The CPU 11 proceeds to step S110 if the remaining amount of the second ink is greater than the remaining amount of the first ink (“Yes” in step S102), and proceeds to step S130 otherwise (“No” in step S102). That is, in the printer 50, when the remaining amount of the second ink is equal to or less than the remaining amount of the first ink, it is less necessary (no) to use the second ink when printing on the designated medium. use. In this embodiment, the CPU 11 allows the user to specify the specific mode on a predetermined UI screen on condition that the remaining amount of the second ink is larger than the remaining amount of the first ink.

  In step S111, the CPU 11 determines the remaining amount ratio of both inks (the remaining amount of the first ink / the remaining amount of the second ink) based on the information on the remaining amounts of the first ink and the second ink acquired in step S102. Is calculated. In step S113, the UI control unit 13e causes the display unit to display a UI screen for selecting a desired LUT from the plurality of rewrite color conversion LUTs 22 ′.

  FIG. 10 illustrates the selection UI screen 30b displayed in step S113. The difference between the selection UI screen 30b and the selection UI screen 30a (FIG. 8) is that, in the selection UI screen 30b, one rewritten color conversion LUT 22 ′ in a plurality of rewritten color conversion LUTs 22 ′ is displayed in a specific manner ( Recommended display). For example, the CPU 11 determines an LUT to be recommended for display according to the remaining ratio, and causes the UI control unit 13e to display a recommendation for the determined LUT. Specifically, the smaller the remaining amount ratio is, the more the first ink is significantly reduced. Therefore, the smaller the remaining amount ratio is, the more the ratio (the first color of the normal color conversion LUT 22). The rewritten color conversion LUT 22 ′ having a high ratio of the second ink in the ratio of the ink amount to the ink amount of the first ink and the second ink) is set as a recommended display target. It is assumed that the correspondence relationship between the remaining amount ratio and the above-described ratio for the rewritten color conversion LUT 22 ′ to be recommended for display is determined in accordance with the remaining amount ratio. In the example of FIG. 10, four rewrite color conversion LUTs 22 ′ (four rewrite color conversion LUTs 22 ′ whose replacement ratios with PK ink are 10%, 20%, 30%, and 40%, respectively) are prepared in advance for the first medium. The rewritten color conversion LUT 22 ′ (replacement rate to PK 40%) having the highest saving effect of the first ink is recommended and displayed.

  The user can arbitrarily select any one of the plurality of check boxes CB in the selection UI screen 30b including the check box CB related to the recommended display by operating the operation unit 40. As described above, according to the third embodiment, according to the remaining amount ratio between the first ink and the second ink in the printer 50, the rewrite color conversion LUT 22 ′ suitable for eliminating the uneven decrease of the first ink at that time is provided. Recommended display is performed on the selection UI screen 30b. Therefore, the user can easily select such an appropriate rewrite color conversion LUT 22 ′. In addition, on the selection UI screen 30b, the description and the like are displayed so that the rewriting color conversion LUT 22 ′ can be selected together with the above recommended display. Therefore, the user can select a rewritten color conversion LUT 22 ′ other than the recommended one by his / her own judgment while recognizing which rewritten color conversion LUT 22 ′ is recommended at that time.

  Note that the LUT that is the target of the recommended display is not limited to the one that is determined with emphasis on eliminating the uneven decrease in the first ink. For example, as illustrated in FIG. 11, the UI control unit 13 e has a rewritten color conversion LUT 22 with the highest image quality retention effect among a plurality of rewritten color conversion LUTs 22 ′ prepared for one medium type. ′ (In the examples of FIGS. 8, 10, and 11, the rewrite color conversion LUT 22 ′ with “image quality priority PK replacement rate 10%”) may be the target of recommended display regardless of the remaining ratio. . With such a configuration, the rewritten color conversion LUT 22 ′ having the highest image quality retention effect among the plurality of rewritten color conversion LUTs 22 ′ can be easily selected on the selection UI screen 30b. Even when the ink is used in combination, it is convenient for the user who wants to realize the same image quality as when only the first ink is used. Further, even when the rewritten color conversion LUT 22 ′ having the highest image quality retention effect is recommendedly displayed, the UI control unit 13 e performs the other rewritten color conversion LUT 22 ′ to be recommended displayed according to the remaining amount ratio. By displaying in another specific display mode (semi-recommended display), it may be easy for the user to select.

5. Modifications The present invention is not limited to the above-described embodiments, and can be implemented in various modes without departing from the scope of the invention. For example, the following modifications are possible. The combined contents of the above-described embodiments and modifications are also within the scope of the present disclosure.

Modification 1:
In step S120 (FIG. 1) and step S116 (FIGS. 7 and 9), the LUT setting unit 13f sets the ink amount of the second ink defined by the set rewrite color conversion LUT 22 ′ between the first ink and the second ink. Further correction may be made according to the difference in color development characteristics.

  FIG. 12 illustrates the color development characteristics of the first ink (MK ink) and the second ink (PK ink). In FIG. 12, the horizontal axis represents the ink amount in the above-described density (%) (ink coverage relative to the unit area of the medium), and the vertical axis represents the lightness L *. These color development characteristics are obtained by measuring the color of a predetermined test pattern (for example, a gradation pattern in which the ink amount is gradually changed) printed on the first medium (mat paper) with the first ink (lightness L *) And a result (color value L *) obtained by measuring the color of a predetermined test pattern printed on the first medium (matte paper) with the second ink (for example, a gratation pattern in which the ink amount is gradually changed). ). As can be seen from FIG. 12, the PK ink has a characteristic that the lightness L * corresponding to the same ink amount is generally higher than that of the MK ink. In other words, the ink amount of PK ink necessary for realizing a certain lightness L * on the mat paper is larger than the ink amount of MK ink necessary for realizing the same lightness L * on the mat paper.

  Therefore, the computer 10 determines the correspondence between the ink amount of MK ink and the ink amount of PK ink that realizes the same lightness L * (for example, the ink amount Im of MK ink that realizes lightness L * 1 and the ink amount of PK ink). (Refer to FIG. 12) and a conversion function for realizing the conversion between the corresponding ink amounts (for example, conversion from the ink amount Im to the ink amount Ip). Alternatively, a conversion table is generated in advance. The conversion function or conversion table generated in advance in this way is stored in the HDD 20 as the ink amount correction data 23 in association with the combination of the first ink and the second ink.

  In step S120 (FIG. 1) and step S116 (FIGS. 7 and 9), the LUT setting unit 13f sets the second ink amount of the set rewrite color conversion LUT 22 ′ to the combination of the first ink and the second ink. Is corrected (converted) by the ink amount correction data 23 stored in the HDD 20 in association with. In the above-described ink amount distribution (replacement), the ink amount of the first ink and the ink amount of the second ink are equivalently exchanged. For example, as illustrated in FIG. 5, when the ratio is 9: 1, the ink amount of the first ink that is defined as the density 20% in the normal color conversion LUT 22 is 1/10 of the ink amount of the second ink as it is. (The density 2% as the ink amount of the first ink is replaced with the density 2% as the ink amount of the second ink). Therefore, the ink amount of the second ink after being corrected by the ink amount correction data 23 is the same as the amount of ink used for replacement with the second ink in the ink amount (density 20%) of the first ink before the distribution. It can be said that the amount of ink (color L *) equivalent to the color (lightness L *) reproduced on the first medium can be reproduced on the first medium by the ink amount (density 2%) of one ink.

  The LUT setting unit 13f overwrites the set ink amount of the second ink of the rewritten color conversion LUT 22 ′ with the corrected ink amount of the second ink obtained by correcting with the ink amount correction data 23. According to the first modification, when the printer 50 executes printing based on the ink amount data (CMYMKPK data) obtained by color conversion using the rewrite color conversion LUT 22 ′, Despite the combined use of the ink and the second ink, it is possible to obtain a color in the printing result that is very close to the case where the first ink is not replaced with the second ink.

Modification 2:
The ratio for the rewritten color conversion LUT 22 ′ set in step S120 (FIG. 1) and step S116 (FIGS. 7 and 9) may be changed according to an instruction from the outside.

  FIG. 13 shows a flowchart according to such a ratio changing process. This process is executed in step S120 (FIG. 1) and step S116 (FIGS. 7 and 9). When the LUT setting unit 13f acquires the ratio for the set rewrite color conversion LUT 22 ′ (step S300), the UI control unit 13e displays a UI screen showing the ratio in an easily understandable manner on the display unit ( Step S310).

  FIG. 14 illustrates a UI screen 30c displayed in step S310. On the UI screen 30c, a slider bar SB is displayed that is movable on the display R in the range (0 to 100%) of the ratio virtually indicated by a horizontal bar or the like. After step S300, the position (initial position) of the slider bar SB when the UI screen 30c is first displayed is a position corresponding to the ratio (first ink: second ink) acquired in step S300. Yes. For example, when the ratio is a value of 7: 3, the slider bar SB is displayed at a position corresponding to 3/10 of the position of 100% in the display R, that is, a position corresponding to 30% in the display R. Further, the UI screen 30c displays an ink remaining amount that simulates the remaining amount of ink (gray display portion) in each ink cartridge of the first ink (MK ink) and the second ink (PK ink). As the ink remaining amount display, a display corresponding to “before printing” and a display corresponding to “after printing” are displayed.

  The ink remaining amount display “before printing” indicates the current remaining amount of the first ink (MK ink) and the remaining amount of the current second ink (PK ink), and at a predetermined position of the remaining amount of the first ink. A virtual line VL1 is drawn. The current remaining amount of the first ink and the current remaining amount of the second ink displayed here are amounts based on the information acquired as described in step S102 (FIG. 9). The virtual line VL1 predicts that when printing is performed without replacing the ink amount from the first ink to the second ink (that is, the ratio = 10: 0), the first ink is consumed up to that position. It is a line for showing to the user. However, how much the first ink is reduced when printing is executed without actually replacing the ink amount from the first ink to the second ink depends on the contents, size, number of prints, etc. of the image to be printed. Since the position depends on the element, the position of the virtual line VL1 is only a hypothetical one, and the position has no strict meaning. The virtual line VL1 is effective when the user compares the “before printing” ink remaining amount display with the “after printing” ink remaining amount display to help the user understand. .

  On the other hand, in the ink remaining amount display “after printing”, the position of the slider bar SB indicates the ink amount corresponding to the difference between the current remaining amount of the first ink and the remaining amount indicated by the virtual line VL1. Thus, assuming that the amount of the second ink is replaced with the amount of the second ink, the reduction mode of the first ink and the second ink is predicted and shown. For example, when the ratio indicated by the slider bar SB is 30%, the difference between the current remaining amount of the first ink and the remaining amount indicated by the virtual line VL1 (the virtual line VL1 in the ink remaining amount display “before printing”) The ink amount corresponding to 3/10 of the upper gray display portion) is subtracted from the current remaining amount of the second ink, and the current remaining amount and the virtual line VL1 for the first ink are displayed. Of the difference from the remaining amount shown, the ink amount corresponding to 7/10 is subtracted from the current remaining amount of the first ink and displayed. In other words, the user can print by replacing the first ink with the second ink at a ratio indicated by the slider bar SB as compared with the normal printing in which the first ink is consumed up to the virtual line VL1 by looking at the ink remaining amount display. Sometimes it is possible to intuitively understand how much the consumption of the first ink can be suppressed and how much the second ink is consumed. In the example of FIG. 14, the virtual line VL <b> 1 is shown in the same position as the “before printing” ink remaining amount display in the “after printing” ink remaining amount display. In addition, the virtual line VL2 in the ink remaining amount display “after printing” indicates the current remaining amount position of the first ink, and the virtual line VL3 in the ink remaining amount display “after printing” is the current amount of the second ink. The remaining position is shown.

  In step S320, the LUT setting unit 13f determines whether the ratio has been changed. The user can arbitrarily change the position of the slider bar SB by operating the operation unit 40. Therefore, when the slider bar SB is moved via the operation unit 40, the LUT setting unit 13f determines that the ratio is changed to a ratio corresponding to the position of the slider bar SB after the movement, and proceeds to step S330. In step S330, the UI control unit 13e updates the “after printing” ink remaining amount display on the UI screen 30c according to the ratio corresponding to the position of the slider bar SB after the movement. For example, when the slider bar SB is changed to the position of 20% (that is, the ratio = 8: 2), 2 / of the difference between the current remaining amount of the first ink and the remaining amount indicated by the virtual line VL1. Ink corresponding to 8/10 of the difference between the current remaining amount of the first ink and the remaining amount indicated by the virtual line VL1 is subtracted from the current remaining amount of the second ink. The ink remaining amount display “after printing” is updated to the display content in which the amount is subtracted from the current remaining amount of the first ink. Thereby, the UI screen 30c including the slider bar SB whose position has been changed and the updated “after printing” ink remaining amount display is displayed (step S310).

  That is, the height of the gray display portion in the ink remaining amount display “after printing” is automatically updated in conjunction with the movement of the slider bar SB by the user. After step S310, when it is determined in step S320 that the ratio has not been changed, the LUT setting unit 13f determines whether or not the determination of the ratio is instructed in step S340. The user can operate the determination button DB (FIG. 14) by operating the operation unit 40. Therefore, when the determination button DB is operated, the LUT setting unit 13f recognizes that the ratio is instructed and proceeds to step S350. On the other hand, steps S310 to S340 are repeated until the ratio determination is instructed.

  In step S350, the LUT setting unit 13f sets the ink amount of the first ink defined in the normal color conversion LUT 22 at a ratio corresponding to the position indicated by the slider bar SB when the determination instruction is received in step S340. A new rewrite color correction LUT 22 ′ that defines the ink amounts of the first ink and the second ink and that defines the ink amounts of the first ink and the second ink after distribution is generated, and this rewrite color conversion LUT 22 ′ is generated. Set. After this, the process proceeds to step S140. According to the second modification, the user can observe the UI screen 30c, and can effectively reduce the unevenness of the first ink by replacing the first ink with the second ink before the printer 50 actually prints. Can be confirmed, and an optimal replacement ratio that can achieve the desired degree of partial reduction elimination effect can be determined.

Modification 3:
Up to now, as specific examples of the first ink and the second ink which are the same color ink and have different characteristics, the first ink is the MK ink and the second ink is the PK ink. However, various combinations of the first ink and the second ink are conceivable.
For example, the first ink may be PK ink and the second ink may be MK ink. With this configuration, it is possible to suppress the uneven decrease in the PK ink according to the remaining amount ratio between the PK ink and the MK ink, and to compensate for the reduced consumption of the PK ink by using the MK ink.
In addition, when using the printer 50 that can use LK ink or LLK ink in addition to black ink (MK ink or PK ink), one kind of ink among black ink, LK ink, and LLK ink is used as the first ink. Another ink may be the second ink. With this configuration, the use of LK ink or LLK ink can compensate for the decrease in black ink consumption and the reduction in black ink consumption according to the remaining ratio between the first ink and the second ink. The amount of decrease in the LK ink (or LLK ink) can be suppressed and the consumption of the LK ink (or LLK ink) can be reduced by using black ink or the like.

Furthermore, when the printer 50 can simultaneously use a pigment-based ink and a dye-based ink for a certain color (for example, black), one of the same-colored pigment-based ink and the dye-based ink is used. The first ink may be used and the other may be the second ink. With such a configuration, according to the remaining ratio of the pigment ink and the dye ink of the same color system, the uneven decrease of one ink is suppressed and the consumption of one ink is reduced by using the other ink. Can be supplemented.
Furthermore, the relationship between the first ink and the second ink may be applied to chromatic inks of the same color system, for example, C ink and LC ink, M ink and LM ink, or the like.
Furthermore, the present invention can be applied not only to ink jet printers but also to printers of various printing systems such as laser printers. In this specification, “ink” is not limited to liquid ink but is used in a broad sense including toner used in laser printers. As other terms having such a broad meaning of “ink”, “coloring material”, “coloring material”, “coloring agent”, and the like can also be used.

DESCRIPTION OF SYMBOLS 10 ... Computer, 11 ... CPU, 12 ... RAM, 13 ... Printer driver, 13a ... Image data acquisition part, 13b ... Color conversion processing part, 13c ... HT processing part, 13d ... Rasterization processing part, 13e ... UI control part, 13f ... LUT setting section, 20 ... HDD, 22, 22 ', 55, 55' ... color conversion LUT, 23 ... ink amount correction data, 30 ... display, 30a, 30b ... selection UI screen, 30c ... UI screen, 40 ... Operation unit, 50 ... printer, 51 ... CPU, 52 ... RAM, 53 ... ROM, 59 ... operation panel, 61, 61a, 61b, 61c, 61d, 61e ... ink cartridge

Claims (8)

A printing apparatus that can use a first ink and a second ink that are inks of the same color and have different characteristics, for printing,
When the designation of a specific mode for saving the first ink is accepted as the print mode, the ratio between the first ink and the second ink, and coloring by printing using the first ink of the two inks A printing apparatus, wherein the first ink and the second ink are used for printing in accordance with a ratio that realizes color development in which a difference between the first and second inks falls within a predetermined allowable range. A color conversion table in which an ink amount for each ink type used for printing is registered in association with a plurality of input grid points expressed in a predetermined input color system, and the first ink and the second ink are registered. The normal color conversion table in which only the ink amount of the first ink is registered as the ink amount for the corresponding color, and the ink amount of the first ink registered in the normal color conversion table as the ink amount for the color is the above ratio. A storage unit storing a rewritten color conversion table in which the amount of each ink distributed to the first ink and the second ink is registered;
When the specification of the specific mode is accepted, the image data representing the image to be printed in the input color system is color-converted using the rewrite color conversion table,
When the designation of a printing mode other than the specific mode is accepted, the image data is color-converted using a normal color conversion table,
The printing apparatus according to claim 1, wherein printing is performed based on ink amount data generated by color conversion. The storage unit stores a plurality of rewritten color conversion tables generated by differentiating the ratio when the ink amount of the first ink is divided into the ink amount of the first ink and the ink amount of the second ink,
3. The color conversion table used for color conversion is selected from a plurality of rewritten color conversion tables in response to an instruction from the outside when designation of the specific mode is received. Printing device. A display control unit for displaying a user interface screen for selecting a color conversion table used for color conversion from a plurality of rewritten color conversion tables on a predetermined display unit;
In the user interface screen, the display control unit includes either a color conversion table that has a relatively high saving effect of the first ink among a plurality of rewritten color conversion tables or a color conversion table that realizes a relatively high image quality. The printing apparatus according to claim 3, wherein the image is displayed as a recommended color conversion table in a specific display mode. The first ink is an ink that adheres to the first medium and produces a predetermined color, and the second ink is an ink that adheres to a second medium different from the first medium and produces a predetermined color,
5. The printing apparatus according to claim 1, wherein the specific mode can be designated on the condition that the designation of the first medium as a medium used for printing is accepted.   6. The specific mode can be specified on condition that the remaining amount of the second ink is larger than the remaining amount of the first ink in the printing apparatus. The printing apparatus as described. A printing control method for controlling a printing apparatus that can use a first ink and a second ink, which are inks of the same color and have different characteristics, for printing,
When the designation of a specific mode for saving the first ink is accepted as the print mode, the ratio between the first ink and the second ink, and coloring by printing using the first ink of the two inks A printing control method characterized in that the first ink and the second ink are used for printing by the printing apparatus in accordance with a ratio that realizes color development that is within a predetermined allowable range. A print control program for controlling a printing apparatus that can use a first ink and a second ink having the same color and different characteristics for printing,
When the designation of a specific mode for saving the first ink is accepted as the print mode, the ratio between the first ink and the second ink, and coloring by printing using the first ink of the two inks A printing control program that causes the printing apparatus to use the first ink and the second ink in accordance with a ratio that achieves color development in which the difference between the two is within a predetermined allowable range.