JP2015211416A - Control device for controlling printing execution part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent colors in results of two kinds of monochromatic printing from being different in the case where a coloring material to be utilized for monochromatic printing for a portion of a target image is different from a coloring material to be utilized for monochromatic printing for remaining portions of the target image.SOLUTION: In the situation where a remaining quantity of any one of CMY inks is equal to or less than a predetermined value, a multifunctional machine performs correction processing that is color conversion processing utilizing an actual correction table ACT on RGB image data RID4 to generate partial print data PD4 for four-color monochromatic printing for a portion of the target image and generates partial print data PD5 for single-color monochromatic printing for remaining portions of the target image thereafter without executing the correction processing. In the situation where remaining quantities of all the CMY inks are greater than the predetermined value, the multifunctional machine generates print data PD3 for four-color monochromatic printing for the entire target object without executing the correction processing.

Description

  In the present specification, print execution capable of executing the first type of monochrome printing using the first type of color material group and executing the second type of monochrome printing using the second type of color material group is possible. A control device for controlling the unit is disclosed.

  Patent Document 1 discloses a printer that generates an alternative color using three color materials of cyan, magenta, and yellow when the black color material runs out.

JP-A-8-192541

  In the technique of the above-mentioned Patent Document 1, for example, when black color material is used and black color material is exhausted after partial monochrome printing of a target image to be printed is performed, cyan or the like is used. Using the three color materials, monochrome printing of the remaining portion of the target image can be performed. In this case, the color of the result of the former monochrome printing and the color of the result of the latter monochrome printing can be greatly different.

  In the present specification, when the color material used for monochrome printing of a part of the target image is different from the color material used for monochrome printing of the remaining part of the target image, the former monochrome material is used. Disclosed is a technique for suppressing the difference between the color resulting from printing and the color resulting from the latter monochrome printing.

  In the present specification, print execution capable of executing the first type of monochrome printing using the first type of color material group and executing the second type of monochrome printing using the second type of color material group is possible. A control device for controlling the unit is disclosed. The control device stores a correction data for approximating a result of the first type monochrome printing to a result of the second type monochrome printing, and target image data for acquiring target image data representing the target image to be printed An acquisition unit, a print data generation unit that generates print data using target image data, and a supply unit that supplies the print data to the print execution unit. In the first situation, the print data generation unit uses the target image data to generate first print data including the first partial print data and the second partial print data. In a different second situation, the second print data is generated using the target image data. In the first situation, the print data generation unit performs a correction process using the correction data on the target image data, and performs the first type of the first partial image that is a part of the target image. First partial print data for monochrome printing is generated, and correction processing using correction data is not performed on target image data, and the second partial image that is the remaining portion of the target image The second partial print data for the second type of monochrome printing is generated, and in the second situation, all the target images are processed without performing correction processing using the correction data on the target image data. Second print data for the first type of monochrome printing is generated.

  In the above configuration, in the first situation, the control device executes correction processing using correction data for approximating the result of the first type monochrome printing to the result of the second type monochrome printing, The first partial print data is generated, and the second partial print data is generated without executing the correction process. For this purpose, the control device, in the first situation, the color resulting from the first type of monochrome printing of the first partial image, the color resulting from the second type of monochrome printing of the second partial image, It is possible to cause the print execution unit to appropriately execute the first type of monochrome printing of the first partial image and the second type of monochrome printing of the second partial image while suppressing the difference between the two. In the second situation, the control device can cause the print execution unit to appropriately execute the first type monochrome printing of the target image.

  A control method, a computer program, and a computer-readable recording medium storing the computer program for realizing the image processing apparatus are also novel and useful.

1 shows a configuration of a communication system. An example of two monochrome printing tables is shown. The flowchart of an actual correction table production | generation process is shown. An example of variation data and difference data is shown. An example of coefficient data is shown. An example of an actual correction table is shown. 2 shows a flowchart of a printing process. 6 shows a flowchart of a corrected double-sided monochrome printing process. The figure for demonstrating the printing process of each case is shown. The figure for demonstrating 2nd Example is shown.

(Configuration of communication system 2)
As shown in FIG. 1, the communication system 2 includes a multi-function device 10 and a PC (abbreviation of personal computer) 50. The multi-function device 10 and the PC 50 can communicate with each other via a LAN (abbreviation of Local Area Network) 4.

(Configuration of multi-function device 10)
The multi-function device 10 includes an operation unit 12, a display unit 14, a print execution unit 16, a scan execution unit 22, a communication interface 24, and a control unit 30. Each part 10-30 is mutually connected via the bus line (symbol abbreviation). The operation unit 12 includes a plurality of keys. The user can input various instructions to the multi-function device 10 by operating the operation unit 12. The display unit 14 is a display for displaying various information. The print execution unit 16 executes printing according to the inkjet method. The scan execution unit 22 executes a scan according to a CCD (abbreviation for Charge Coupled Device) method or a CIS (abbreviation for Contact Image Sensor) method. The communication interface 24 is connected to the LAN 4. The control unit 30 controls operations of the display unit 14, the print execution unit 16, the scan execution unit 22, and the like.

  The print execution unit 16 further includes four ink cartridges 18C, 18M, 18Y, and 18K, and four remaining amount sensors 20C, 20M, 20Y, and 20K. The ink cartridges 18C, 18M, 18Y, and 18K store cyan, magenta, yellow, and black inks, respectively. The print execution unit 18 executes printing using ink in the ink cartridge 18C and the like. In the following, cyan, magenta, yellow, and black may be referred to as “C”, “M”, “Y”, and “K”. CMY ink, that is, chromatic ink, is a dye, and K ink, that is, achromatic ink, is a pigment. The remaining amount sensors 20C, 20M, 20Y, and 20K detect the remaining amount of ink in the ink cartridges 18C, 18M, 18Y, and 18K, respectively, and supply a remaining amount signal indicating the remaining amount to the control unit 30.

  The control unit 30 includes a CPU 32 and a memory 34. The CPU 32 is a processor that executes various processes according to the program RGM stored in the memory 34. For example, the CPU 32 executes a process of generating an actual correction table ACT and storing the actual correction table ACT in the memory 34 in accordance with a flowchart of FIG. Further, for example, the CPU 32 converts RGB image data representing the target image to be printed into CMYK image data, converts the CMYK image data into print data, and converts the print data into the print execution unit 18 in accordance with the flowchart of FIG. The process to supply to is executed.

  The RGB image data representing the target image is bitmap data composed of a plurality of RGB pixel data. The RGB pixel data includes an R value, a G value, and a B value within the range of “0” to “255”. That is, the RGB pixel data indicates 256 gray scale pixel values in the RGB color space. The CMYK image data is bitmap data composed of a plurality of CMYK pixel data. The CMYK pixel data includes C value, M value, Y value, and K value within the range of “0” to “255”. That is, the CMYK pixel data indicates 256 gray scale pixel values in the CMYK color space. The print data is bitmap data composed of a plurality of binary pixel data. The binary pixel data includes “1” or “0” for each of CMYK. Here, “1” indicates that dots are formed by ejecting ink, and “0” indicates that dots are not formed. In the modification, the pixel data constituting the print data may be data indicating any one of three or more values. For example, the pixel data constituting the print data includes a value indicating that a large dot is formed, a value indicating that a medium dot is formed, a value indicating that a small dot is formed, and that no dot is formed. It may be data indicating any one of the four values.

  The memory 34 stores five tables FPT, SPT, CPT, DCT, ACT and test image data TID in addition to the program PGM. Each of the five tables FPT is a lookup table for converting RGB image data into CMYK image data. As described above, the actual correction table ACT is generated by the CPU 32 and stored in the memory 34. On the other hand, the other four tables FPT, SPT, CPT, and DCT are stored in the memory 34 in advance from the shipment stage of the multi-function device 10. The test image data TID is used for printing a test image TI (see FIG. 3) described later.

(4-color monochrome printing table FPT; FIG. 2)
The four-color monochrome printing table FPT converts RGB image data into CMYK image data when monochrome printing (hereinafter referred to as “four-color monochrome printing”) is performed using four colors of CMYK inks. Used for. As shown in FIG. 2, the four-color monochrome printing table FPT has a plurality of gradations corresponding to a plurality of gradations (17 gradations such as “0”, “16”... “255” in this embodiment). Including combination data. Each combination data is data in which RGB pixel data and CMYK pixel data are associated with each other. For example, in the combination data corresponding to the gradation “0”, the RGB pixel data “0, 0, 0” and the CMYK pixel data “30, 28, 30, 130” are associated with each other. This means that RGB pixel data “0, 0, 0” indicating black in the RGB image data is converted into CMYK pixel data “30, 28, 30, 130”. Further, for example, the combination data corresponding to the gradation “255” means that RGB pixel data “255, 255, 255” indicating white is converted into CMYK pixel data “0, 0, 0, 0”. To do.

  Note that the RGB pixel data not included in the 17 combination data in the 4-color monochrome print table FPT is converted into CMYK pixel data by a complementing process using the two combination data. For example, the RGB pixel data “8, 8, 8” is converted into CMYK pixel data “30” by a complementary process using combination data corresponding to the gradation “0” and combination data corresponding to the gradation “16”. , 28, 30, 110 ". Note that the point that such a complementing process is executed is the same in other tables SPT and the like described later.

(Monochromatic monochrome printing table SPT; FIG. 2)
The monochrome monochrome printing table SPT is used to convert RGB image data into CMYK image data when monochrome printing (hereinafter referred to as “monochrome monochrome printing”) using only K ink is to be executed. . Similar to the four-color monochrome print table FPT, the single-color monochrome print table SPT includes 17 combination data (that is, a combination of RGB pixel data and CMYK pixel data) corresponding to 17 gradations. In monochrome monochrome printing, only K ink is used, so the C value, M value, and Y value included in the CMYK pixel data are “0”, respectively.

(Color printing table CPT)
The color printing table CPT (see FIG. 1) is used to convert RGB image data into CMYK image data when color printing is to be performed using four colors of CMYK ink. Although specific data is not shown, the color printing table CPT includes a plurality of combination data corresponding to a plurality of gradations larger than those of the monochrome printing tables SPT and FTP.

(4-color monochrome printing and monochrome monochrome printing)
Next, a situation in which four-color monochrome printing and single-color monochrome printing are executed will be described. In the present embodiment, the multi-function device 10 executes monochrome printing on both sides of the printing medium when the single-sided printing instruction for executing monochrome printing on only one side of the printing medium is obtained from the PC 50. When a double-sided printing instruction for execution is obtained from the PC 50, four-color monochrome printing is usually executed. The reason why the four-color monochrome printing is executed in accordance with the duplex printing instruction is as follows.

  For example, assume a situation where monochrome monochrome printing is executed in accordance with a duplex printing instruction. In such a situation, the multi-function device 10 first moves one side of the print medium while moving the print medium inside the print medium transport path of the multi-function device 10 (hereinafter referred to as “path inside”). Then, monochrome printing using only K ink is executed, and the print medium is temporarily discharged to the outside of the above-described conveyance path of the multi-function device 10. After that, the multi-function device 10 takes the print medium again into the path of the multi-function device 10, and further moves the print medium within the path of the multi-function device 10, while applying only K ink to the other surface of the print medium. Execute the monochrome printing that was used. At this time, the K ink attached to one surface may not be dry. This phenomenon appears more prominently when K ink, which is a pigment that does not easily penetrate into the print medium, is used. Therefore, when the printing medium on which the monochrome printing on one side is finished is moved within the path of the multi-function device 10, the K ink adhering to the one surface becomes a member inside the path of the multi-function device 10 (for example, the print medium A roller for movement, a platen for supporting a print medium, etc.). If a member inside the path of the multi-function device 10 is soiled by K ink, the K ink may adhere to a print medium on which printing is subsequently performed, and thus there is a possibility that an appropriate print result cannot be provided to the user. is there.

  In view of the above situation, the multi-function device 10 according to the present embodiment performs double-sided monochrome printing using four colors of CMYK while reducing the amount of K ink used. As a result, the amount of K ink that adheres to one side of the print medium is reduced, so that even if the print medium is moved within the path of the multi-function device 10 for printing on the other side of the print medium, there are many It is possible to suppress the members inside the path of the functional unit 10 from being stained with K ink. Note that CMY inks are dyes that easily penetrate into the print medium. For this reason, there is a low possibility that the members inside the path of the multi-function device 10 are stained by the CMY ink attached to one surface of the print medium.

  As described above, the multi-function device 10 normally performs four-color monochrome printing when a double-sided printing instruction is obtained from the PC 50. However, for example, when double-sided printing is to be performed on a plurality of print media, when four-color monochrome printing is completed on some print media of the plurality of print media, any remaining CMY inks remain. The amount can be zero. In this case, after the four-color monochrome printing for the above-mentioned part of the printing media is completed, the printing is interrupted and the user is requested to replenish the ink. After the ink is replenished, the remaining printing of the plurality of printing media A method for resuming four-color monochrome printing on a medium is conceivable. However, when printing is interrupted, the user may feel inconvenient. For this reason, the multi-function device 10 according to the present embodiment executes the monochrome monochrome printing on the remaining printing medium without interrupting the printing. Thereby, even if the user does not replenish ink, double-sided printing on a plurality of print media is completed, so that the convenience for the user can be improved. As described above, in this embodiment, when double-sided printing is to be performed on a plurality of printing media, members in the path of the multi-function device 10 are soiled in a normal situation where CMY ink is sufficiently present. Therefore, four-color monochrome printing is executed for all print media. On the other hand, in the special situation where any remaining amount of CMY ink is zero when four-color monochrome printing is completed for some print media, the remaining print media are considered in consideration of user convenience. Monochromatic monochrome printing is executed.

  However, the ink colors used differ in two types of monochrome printing, four-color monochrome printing and single-color monochrome printing. For this reason, the following problems may occur. For example, a situation is assumed in which double-sided printing of the same image is executed on a plurality of print media, such as New Year's card printing. In such a situation, the printing result of the four-color monochrome printing for some printing media and the printing result of the monochrome printing for the remaining printing media can be provided to the user. In this case, although the monochrome printing of the same image is being executed, the color of the former printing result and the color of the latter printing result can be greatly different, which can give the user a sense of incongruity. In order to suppress this, in this embodiment, a default correction table DCT or an actual correction table ACT described below is used.

(Default correction table DCT and actual correction table ACT)
The default correction table DCT and the actual correction table ACT (see FIG. 1) are used when the special situation in which any remaining amount of CMY ink is zero during the four-color monochrome printing is expected to occur. It is used to convert image data into CMYK image data for four-color monochrome printing. That is, the correction tables DCT and ACT are used in place of the four-color monochrome printing table FPT when the above-described special situation is expected to occur. Although specific data will be described later, each of the correction tables DCT and ACT includes 17 combination data (that is, a combination of RGB pixel data and CMYK pixel data) corresponding to 17 gradations. Each correction table DCT, ACT is a table for approximating the printing result of four-color monochrome printing to the printing result of single-color monochrome printing.

(Actual correction table generation processing; FIG. 3)
Next, the contents of the actual correction table generation process executed by the CPU 32 of the multi-function device 10 will be described with reference to FIG. The CPU 32 starts the process of FIG. 3 when an operation for generating the actual correction table ACT is performed on the operation unit 12 by the user.

  In S10, the CPU 32 uses the test image data TID in the memory 34 to generate print data. Next, in S <b> 12, the CPU 32 executes print processing for supplying the print data generated in S <b> 10 to the print execution unit 16. As a result, the print execution unit 16 prints the test image TI on the print medium.

  The content of the process of S10 will be described in detail with reference to the test image TI. The test image TI includes a four-color area FA obtained by four-color monochrome printing and a single-color area SA obtained by single-color monochrome printing. The other area in the test image TI may be obtained by four-color monochrome printing, or may be obtained by a single-color monochrome area. Each of the four-color area FA and the single-color area SA includes 17 partial areas corresponding to 17 gradations. For example, the four-color area FA includes a partial area FA0 corresponding to the gradation “0”, and the single-color area SA includes a partial area SA0 corresponding to the gradation “0”.

  Test image data TID representing the test image TI is composed of a plurality of first RGB pixel data. The plurality of first RGB pixel data includes 17 RGB pixel data groups (hereinafter referred to as “4-color RGB pixel data group”) representing 17 partial areas included in the 4-color area FA, and a single-color area. 17 RGB pixel data groups (hereinafter referred to as “monochromatic RGB pixel data groups”) representing 17 partial areas included in SA. For example, one 4-color RGB pixel data group representing the partial area FA0 is composed of two or more first RGB pixel data in which all of the R value, the G value, and the B value are “0”. . Similarly, one single-color RGB pixel data group representing the partial area SA0 is composed of two or more first RGB pixel data in which all of the R value, the G value, and the B value are “0”. .

  The CPU 32 performs color conversion on the 17 4-color RGB pixel data groups in the test image data TID using the 4-color monochrome print table FPT, and generates 17 CMYK pixel data groups. Further, the CPU 32 performs color conversion on the 17 monochrome RGB pixel data groups in the test image data TID using the monochrome monochrome printing table SPT, and generates 17 CMYK pixel data groups. Note that color conversion using any of the tables FPT and SPT may be performed on each of the other first RGB pixel data in the test image data TID. As a result, the CPU 32 generates CMYK image data including a plurality of CMYK pixel data. Then, the CPU 32 performs halftone processing on the CMYK image data, and generates print data composed of a plurality of binary pixel data.

  As described above, the four-color area FA and the single-color area SA in the test image TI are obtained by four-color monochrome printing according to the four-color monochrome printing table FPT and single-color monochrome printing according to the single-color monochrome printing table SPT, respectively. . Since the ink colors used in the two types of monochrome printing are different, the colors of two partial areas (for example, FA0 and SA0) corresponding to the same gradation are different.

  Next, in S14, the CPU 32 causes the scan execution unit 22 to scan the print medium on which the test image TI is printed. Thereby, the CPU 32 acquires test scan data representing the test image TI. The test scan data is composed of a plurality of second RGB pixel data. Subsequently, in S16, the CPU 32 generates an actual correction table ACT using the test scan data. Then, the CPU 32 stores the actual correction table ACT in the memory 34.

(Specific processing for generating the actual correction table ACT; FIG. 4)
Next, details of the process of S16 of FIG. 3 will be described with reference to FIG. In S20, the CPU 32 calculates variation data SD1 and SD2 using test scan data. Specifically, the CPU 32 first sets 17 scan pixel data corresponding to 17 partial areas (that is, for each of the four color area FA and the single color area SA in the test image TI represented by the test scan data). 17 scan pixel data corresponding to 17 gradations) is determined. Each scan pixel data includes an R value, a B value, and a G value. When determining one scan pixel data corresponding to one partial area (hereinafter referred to as “target partial area”), the CPU 32 executes the following processing. That is, the CPU 32 first specifies two or more second RGB pixel data representing the target partial region from among the plurality of second RGB pixel data constituting the test scan data. Next, the CPU 32 calculates an average value of two or more R values included in two or more specified second RGB pixel data. Similarly, the CPU 32 calculates an average value of two or more G values and an average value of two or more B values. Then, the CPU 32 determines each calculated average value (that is, the R value, the G value, and the B value) as one piece of scan pixel data corresponding to the target partial region. In the example of FIG. 4, the scan pixel data corresponding to the gradation “0” obtained from the four-color area FA is “36, 35, 30”, and the scan corresponding to the gradation “0” obtained from the single-color area SA. Pixel data is “15, 14, 7”. In the modification, the CPU 32 specifies only one second RGB pixel data representing the target partial area, and specifies one specified scan pixel data corresponding to the target partial area. You may determine R value, G value, and B value which are contained in 2nd RGB pixel data.

  Next, the CPU 32 calculates 17 variation data SD1 corresponding to 17 scan pixel data obtained from the 4-color area FA (that is, 17 variation data SD1 corresponding to 17 gradations). The CPU 32 executes the following processing when calculating one piece of variation data SD1 corresponding to one piece of scan pixel data (hereinafter referred to as “target scan pixel data”) obtained from the four-color area FA. That is, the CPU 32 first specifies the maximum value among the R value, the G value, and the B value included in the target scan pixel data. For example, in the scan pixel data “36, 35, 30” corresponding to the gradation “0”, the maximum value is the R value “36”. Then, the CPU 32 calculates a difference from the maximum value for each of the R value, the G value, and the B value included in the target scan pixel data. For example, in the scan pixel data “36, 35, 30”, the difference C_R between the maximum value “36” and the R value “36” is “0”, and the difference between the maximum value “36” and the G value “35”. C_G is “1”, and the difference C_B between the maximum value “36” and the B value “30” is “6”. The CPU 32 determines data “0, 1, 6”, which is a combination of the three differences C_R, C_G, and C_B, that is, data indicating variations in each value of the scan pixel data as one variation data SD1. Similarly, the CPU 32 also calculates other variation data SD1.

  The CPU 32 calculates 17 variation data SD2 corresponding to 17 scan pixel data obtained from the single color area SA (that is, 17 variation data corresponding to 17 gradations) as in the case of calculating the variation data SD1. SD2) is calculated. For example, based on the scan pixel data “15, 14, 7” corresponding to the gradation “0”, variation data SD2 “0, 1, 8” that is a combination of three differences K_R, K_G, K_B is calculated. The

  In S22, the CPU 32 uses the 17 variation data SD1 and the 17 variation data SD2 to calculate 17 difference data DD corresponding to 17 gradations. Specifically, the CPU 32 uses the variation data SD1 “0, 1, 6” corresponding to the gradation “0” and the variation data SD2 “0, 1, 8” corresponding to the gradation “0”. Then, the R value difference ΔR “0”, the G value difference ΔG “0”, and the B value difference ΔB “−2” are calculated. Then, the CPU 32 determines data “0, 0, −2”, which is a combination of the three differences ΔR, ΔG, and ΔB, as the difference data DD corresponding to the gradation “0”. The CPU 32 similarly calculates the difference data DD for the other gradations. As a result, 17 difference data DD corresponding to 17 gradations are calculated. The difference data DD can be said to be data indicating a difference between the result of the four-color monochrome printing according to the four-color monochrome printing table FPT and the result of the monochrome monochrome printing according to the single-color monochrome printing table SPT. That is, it can be said that the difference data DD is data indicating a difference between the results of two types of monochrome printing.

(Continuation of FIG. 4; FIG. 5)
Next, processing subsequent to FIG. 4 will be described with reference to FIG. In S24, the CPU 32 calculates 17 coefficient data CD corresponding to 17 gradations using 17 difference data DD according to the mathematical formula shown in the upper diagram of FIG. The coefficient data CD is data of a combination of a coefficient CC corresponding to C, a coefficient CM corresponding to M, a coefficient CY corresponding to Y, and a coefficient CK corresponding to K. In the present embodiment, α in the formula is a fixed value “0.02”, but in the modified example, α may be another fixed value (for example, “0.01”, “0.03”, etc.). Good. For example, the coefficient data CD “0.9604, 0.9604, 1.0000, 1.0000” is calculated based on the difference data DD “0, 0, −2” corresponding to the gradation “0”.

(Continuation of FIG. 5; FIG. 6)
Subsequently, processing subsequent to FIG. 5 will be described with reference to FIG. In S26, the CPU 32 generates an actual correction table ACT using the four-color monochrome printing table FPT and the 17 coefficient data CD. Specifically, the CPU 32 multiplies the CMYK pixel data corresponding to the gradation and the coefficient data CD corresponding to the gradation for each of the 17 gradations in the four-color monochrome printing table FTP. Thus, new CMYK pixel data is calculated. For example, the CMYK pixel data “30, 28, 30, 130” corresponding to the gradation “0” in the four-color monochrome print table FTP and the coefficient data CD “0.9604, 0. 9604, 1.0000, 1.0000 "and the new CMYK pixel data" 28, 26, 30, 130 "is calculated. The decimal part is rounded down. Then, the CPU 32 associates the RGB pixel data “0, 0, 0” corresponding to the gradation “0” and the new CMYK pixel data “28, 26, 30, 130” with one combination. Determine the data. The CPU 32 performs the same process for other gradations. As a result, an actual correction table ACT including 17 combination data corresponding to 17 gradations is completed.

  If the difference between the two pieces of variation data SD1 and SD2 in FIG. 4 is large, the difference between the results of two types of monochrome printing of four-color monochrome printing and single-color monochrome printing becomes large. For example, at the gradation “0”, the variation data SD1 is “0, 1, 6”, and the variation data SD2 is “0, 1, 8”. In this case, the difference “2” in the B value leads to a difference in the results of the two types of monochrome printing. Therefore, when processing is performed so that the difference becomes small, the results of two types of monochrome printing can be approximated. Therefore, in this embodiment, the coefficient data CD is calculated according to the difference data DD in S24 of FIG. 5, and the actual correction table ACT is generated according to the coefficient data CD in S26 of FIG. Thereby, the result of 4-color monochrome printing according to the actual correction table ACT can be approximated to the result of monochrome monochrome printing. That is, the actual correction table ACT is data for approximating the results of two types of monochrome printing.

  Although specific data is not shown, the default correction table DCT is generated as follows. That is, the vendor of the multi-function device 10 causes another multi-function device (for example, a so-called master machine) that is the same model as the multi-function device 10 to execute the process of FIG. 3 before the multi-function device 10 is shipped. The vendor stores the actual correction table obtained here as a default correction table DCT in the memory 34 of the multi-function device 10 in advance. As described above, the default correction table DCT is not generated by using the result of monochrome printing actually executed by the multi-function device 10, but is executed by another multi-function device that is the same model as the multi-function device 10. Generated using the result of monochrome printing. Therefore, it can be said that the default correction table DCT is also data for approximating the results of two types of monochrome printing.

(Printing process; FIG. 7)
Next, the contents of the printing process executed by the CPU 32 of the multi-function device 10 will be described with reference to FIG. The user executes a print execution operation for causing the multi-function device 10 to execute printing on the PC 50. The operation includes an operation for specifying RGB image data representing a target image to be printed, and an operation for specifying print settings. Then, when a print execution operation is executed once in the PC 50, the CPU 32 outputs one print instruction including designated RGB image data and print setting information indicating the designated print setting from the PC 50. To get. The CPU 32 starts the process of FIG. 7 when acquiring one print instruction from the PC 50. The print setting information in the print instruction includes color number information indicating the number of printing colors (that is, monochrome printing or color printing), double-sided printing information indicating whether double-sided printing is performed (that is, double-sided printing or single-sided printing), and the number of copies. The number of copies to be shown.

  In the present embodiment, the target images to be printed mean all images to be printed on the print medium according to one print instruction acquired in response to one print execution instruction executed by the user. . For example, when different images are to be printed on a plurality of print media according to the one print instruction, the target image includes a plurality of different images to be printed on the plurality of print media. . In addition, for example, when the same image should be printed on a plurality of print media in accordance with the above one print instruction (that is, when the number of copies is two or more), the target image is printed on a plurality of sheets. Contains a plurality of identical images to be printed on the media. Therefore, in these cases, an image to be printed on a part of the plurality of print media can be referred to as a partial image of the target image. The image to be printed on the remaining print medium of the print media can be referred to as the remaining partial image of the target image.

  In S40, the CPU 32 determines whether or not the remaining amount of K ink is zero. Specifically, the CPU 32 determines that the remaining amount of K ink is zero when the remaining amount signal acquired from the remaining amount sensor 20K (see FIG. 1) indicates that the remaining amount is zero. (YES in S40), the process proceeds to S42. On the other hand, if the remaining amount signal indicates that the remaining amount is greater than zero, the CPU 32 determines that the remaining amount of K ink is not zero (NO in S40), and proceeds to S50.

  In S42, the CPU 32 executes error processing. Specifically, the CPU 32 causes the display unit 14 to display information indicating that printing cannot be executed due to the remaining amount of K ink being zero, without executing printing of the target image. . If the remaining amount of K ink is zero, neither monochrome printing nor color printing of the target image can be performed, and therefore the error process of S42 is performed. When S42 ends, the process of FIG. 7 ends.

  In S50, the CPU 32 determines whether or not single-sided monochrome printing of the target image should be executed. Specifically, the CPU 32 performs single-sided monochrome printing of the target image when the duplex printing information included in the print setting information indicates single-sided printing and the color number information included in the printing setting information indicates monochrome printing. It is determined that it should be executed (YES in S50), and the process proceeds to S52. On the other hand, when the double-sided printing information indicates double-sided printing and / or when the color number information indicates color printing, the CPU 32 determines that single-sided monochrome printing of the target image should not be performed (NO in S50). That is, it is determined that color printing or double-sided monochrome printing of the target image should be executed, and the process proceeds to S60.

  In S52, the CPU 32 executes a single-sided monochrome printing process. Specifically, as shown in FIG. 9, the CPU 32 executes a color conversion process on the acquired RGB image data RID1 using the monochrome monochrome printing table SPT (see FIGS. 1 and 2), and CMYK image data CID1 is generated. Next, the CPU 32 executes halftone processing on the CMYK image data CID1, generates print data PD1, and supplies the print data PD1 to the print execution unit 16. As a result, the print execution unit 16 executes single-sided monochrome printing of the target image. When S52 ends, the process of FIG. 7 ends.

  In S60, the CPU 32 determines whether any remaining amount of the CMY ink is zero. Specifically, when any of the three remaining amount signals acquired from the three remaining amount sensors 20C, 20M, and 20Y (see FIG. 1) indicates that the remaining amount is zero. Then, it is determined that any remaining amount of CMY ink is zero (YES in S60), and the process proceeds to S62. On the other hand, if any of the three remaining amount signals indicates that the remaining amount is greater than zero, the CPU 32 determines that any remaining amount of the CMY ink is not zero (NO in S60), and proceeds to S70. move on.

  In S62, the CPU 32 executes error processing. Specifically, the CPU 32 displays information indicating that printing cannot be performed because the remaining amount of any of the CMY inks is zero without performing printing of the target image. To display. If any remaining amount of the CMY ink is zero, neither color printing nor double-sided monochrome printing of the target image can be executed, and therefore the error process of S62 is executed. When S62 ends, the process of FIG. 7 ends.

  In S70, the CPU 32 determines whether to perform color printing of the target image. Specifically, when the number-of-colors information included in the print setting information indicates color printing, the CPU 32 determines that color printing should be executed (YES in S70), and proceeds to S72. On the other hand, if the color number information indicates monochrome printing, the CPU 32 determines that color printing of the target image should not be executed (NO in S70), that is, should execute double-sided monochrome printing of the target image. Determination is made and the process proceeds to S80.

  In S72, the CPU 32 executes a color printing process. As shown in FIG. 9, the CPU 32 performs color conversion processing on the acquired RGB image data RID2 by using the color printing table CPT (see FIG. 1) to generate CMYK image data CID2. Next, the CPU 32 executes halftone processing on the CMYK image data CID2, generates print data PD2, and supplies the print data PD2 to the print execution unit 16. As a result, the print execution unit 16 performs color printing of the target image. When S72 ends, the process of FIG. 7 ends.

  In S80, the CPU 32 determines whether any remaining amount of the CMY ink is equal to or less than a predetermined value Th. Specifically, the CPU 32 indicates that any of the three remaining amount signals acquired from the three remaining amount sensors 20C, 20M, and 20Y (see FIG. 1) indicates that the remaining amount is equal to or less than the predetermined value Th. If it is determined that the remaining amount of any of the CMY inks is equal to or less than the predetermined value Th (YES in S80), the process proceeds to S90. On the other hand, when any of the three remaining amount signals indicates that the remaining amount is greater than the predetermined value Th, the CPU 32 determines that any remaining amount of the CMY ink is not less than the predetermined value Th (in S80). NO), the process proceeds to S92. The predetermined value Th is a predetermined fixed value. For example, in this embodiment, the predetermined value Th is a value that displays LOW as the ink remaining amount information displayed on the display unit 14 (for example, 1 / of the full ink amount). 10).

  In S90, the CPU 32 determines whether or not the scheduled number of prints, which is the number of print media to be printed, is 2 or more. Specifically, when the number of copies information included in the print setting information indicates two or more, the CPU 32 determines that the planned number of prints is two or more (YES in S90), and proceeds to S100. In addition, even if the number of copies information included in the print setting information indicates one copy, the CPU 32 determines that the RGB image data is data to be printed on two or more print media (for example, the RGB image data is Also, when two or more image data representing two or more images to be printed on two or more print media are included (YES in S90), S100 is determined. Proceed to On the other hand, when the number of copies information included in the print setting information indicates one copy and the RGB image data is data to be printed only on one print medium, the CPU 32 has a planned print number of one. (NO in S90), the process proceeds to S92.

  In S92, the CPU 32 executes a non-corrected duplex monochrome printing process for the target image. As illustrated in FIG. 9, the CPU 32 performs color conversion processing on the acquired RGB image data RID3 using the four-color monochrome print table FPT to generate CMYK image data CID3. Next, the CPU 32 executes halftone processing on the CMYK image data CID3, generates print data PD3, and supplies the print data PD3 to the print execution unit 16. As a result, the print execution unit 16 executes double-sided monochrome printing (that is, four-color monochrome printing) of the target image.

  When any remaining amount of CMY ink is greater than the predetermined value Th (NO in S80), there is usually a special situation in which any remaining amount of CMY ink becomes zero during the four-color monochrome printing of the target image. Does not occur. Even if the remaining amount of any of the CMY inks is equal to or less than the predetermined value Th, the special situation described above does not normally occur when the planned number of printed sheets is 1 (NO in S90). For this reason, when it is predicted that the above-mentioned special situation does not occur (that is, NO in S80 or NO in S90), 4-color monochrome printing according to the 4-color monochrome print table FPT is executed in S92. The When S92 ends, the process of FIG. 7 ends.

  In S100, the CPU 32 executes a corrected double-sided monochrome printing process for the target image. If the remaining amount of any of the CMY inks is equal to or less than the predetermined value Th (YES in S80) and the planned number of prints is 2 or more (YES in S90), the four-color monochrome printing of the target image is in progress. A special situation may occur where any remaining CMY ink is zero. In other words, four-color monochrome printing of a part of the target image can be performed, and then monochrome monochrome printing of the remaining part of the target image can be performed. Accordingly, when the above-described special situation is expected to occur (that is, YES in S90), in S100, the default correction table DCT or the actual correction table ACT is used to approximate the results of the two types of monochrome printing. Then, a corrected double-sided monochrome printing process including a correction process using the above is executed. When S100 ends, the process of FIG. 7 ends.

(Corrected double-sided monochrome printing process; Fig. 8)
Next, details of the processing of S100 of FIG. 7 will be described with reference to FIG. In S110, the CPU 32 sets the number counter P to an initial value “1”. In S120, the CPU 32 determines whether any remaining amount of CMY ink is zero. The process of S120 is the same as the process of S60 of FIG. When the CPU 32 determines that any remaining amount of CMY ink is zero (YES in S120), the CPU 32 proceeds to S122 and determines that any remaining amount of CMY ink is not zero (NO in S120). The process proceeds to S130.

  In S122, the CPU 32 uses the single-color monochrome print table SPT (see FIGS. 1 and 2), and the Pth partial print data representing the Pth partial image to be printed on the Pth print medium. Is generated. Specifically, the CPU 32 executes a color conversion process on the P-th image data representing the P-th partial image among the acquired RGB image data using the monochrome monochrome print table SPT, P-th CMYK image data is generated. Next, the CPU 32 executes halftone processing on the P-th CMYK image data to generate P-th partial print data. When S122 ends, the process proceeds to S140.

  On the other hand, in S130, the CPU 32 determines whether or not the remaining amount of K ink is zero. The process of S130 is the same as the process of S40 of FIG. If the CPU 32 determines that the remaining amount of K ink is zero (YES in S130), the process proceeds to S170. If the CPU 32 determines that the remaining amount of K ink is not zero (NO in S130), the process proceeds to S132. move on.

  In S132, the CPU 32 uses the default correction table DCT or the actual correction table ACT (see FIGS. 1 and 6) to generate P-th partial print data. Specifically, when the actual correction table ACT is not stored in the memory 34 (that is, when the process of FIG. 3 has not been executed yet), the CPU 32 uses the default correction table DCT to obtain the acquired correction table ACT. A color conversion process is executed on the P-th image data of the RGB image data to generate P-th CMYK image data. On the other hand, when the actual correction table ACT is stored in the memory 34 (that is, when the processing of FIG. 3 has been executed), the CPU 32 uses the actual correction table ACT to store the acquired RGB image data. Color conversion processing is executed on the P-th image data, and P-th CMYK image data is generated. Then, the CPU 32 executes halftone processing on the P-th CMYK image data to generate P-th partial print data. When S132 ends, the process proceeds to S140.

  As described above, the default correction table DCT or the actual correction table ACT is data for approximating the results of two types of monochrome printing. Therefore, in S132, it can be said that the color conversion process using the table DCT or ACT is a correction process for approximating the results of two types of monochrome printing. That is, in S132, the CPU 32 executes correction processing using the table DCT or ACT to generate Pth partial print data. On the other hand, in S122, the color conversion process using the table DCT or ACT is not executed. That is, in S122, the CPU 32 generates P-th partial print data without executing correction processing using the table DCT or ACT. Further, in each of the printing processes of S52, S72, and S92 in FIG. 7, the CPU 32 does not execute the correction process using the table DCT or ACT, and print data (that is, any one of PD1 to PD3 in FIG. 9). Is generated.

  In S <b> 140, the CPU 32 supplies the P-th partial print data to the print execution unit 16. In S140 executed through S122, the print execution unit 16 executes monochromatic monochrome printing of the Pth partial image on the Pth print medium. In S140 executed through S132, the print execution unit 16 executes four-color monochrome printing of the Pth partial image on the Pth print medium.

  In S150, the CPU 32 adds “1” to the current value of the sheet counter P to calculate a new value of the sheet counter P.

  In S160, the CPU 32 determines whether or not the current value of the number counter P is larger than the scheduled print number. If the CPU 32 determines that the current value of the number counter P is equal to or less than the scheduled number of printed sheets (NO in S160), the CPU 32 returns to S120. On the other hand, if the CPU 32 determines that the current value of the number counter P is larger than the planned number of printed sheets (YES in S160), the process of FIG.

  If it is determined that the remaining amount of K ink is zero (YES in S130), in S170, the CPU 32 executes an error process. Specifically, the CPU 32 does not generate the partial print data for the Pth sheet and thereafter and supplies the partial print data to the print execution unit 16, that is, executes the printing of the partial image for the Pth sheet and thereafter in the target image. The information indicating that printing cannot be executed is displayed on the display unit 14. When the remaining amount of K ink is zero, neither the four-color monochrome printing or the single-color monochrome printing of the target image can be executed, and therefore the error processing of S170 is executed. When S170 ends, the process of FIG. 8 ends.

(Specific example of corrected double-sided monochrome printing process; FIG. 9)
A specific example of the corrected double-sided printing process (S100 in FIG. 7, see FIG. 8) will be described with reference to FIG. Here, the number of copies information included in the print setting information indicates 20 sheets, and it is assumed that double-sided monochrome printing of the same image should be executed on 20 print media. When the value of the sheet counter P is 1 to 10, the CPU 32 executes the color conversion process for the RGB image data RID4 using the actual correction table ACT, and the 10th CMYK images of the 1st to 10th sheets. Data CID4 is generated, and ten partial print data PD4 for the first to tenth sheets are generated (S132 in FIG. 8). Here, in the first to tenth color conversion processes, the RGB image data RID4 to be processed is the same data. For this reason, the ten CMYK image data CID4 are the same data, and the ten partial print data PD4 are the same data. When the value of the number counter P is 11, the CPU 32 determines that any remaining amount of CMY ink is zero (YES in S120). Therefore, when the value of the sheet counter P is 11 to 20, the CPU 32 executes the color conversion process for the RGB image data RID4 using the monochrome monochrome print table SPT, and performs the 11th to 20th sheets. Ten CMYK image data CID5 are generated, and ten partial print data PD5 of the 11th to 20th sheets are generated (S122 in FIG. 8). Here, even in the color conversion processing of the 11th to 20th sheets, the RGB image data RID4 to be processed is the same data. For this reason, the ten CMYK image data CID5 are the same data, and the ten partial print data PD5 are the same data.

(Effects of the first embodiment)
For example, it is conceivable to adopt the configuration of the comparative example shown in FIG. In the configuration of the comparative example, the color conversion process using the four-color monochrome print table FPT is executed, and the tenth partial print data of the first to tenth sheets are generated. When printing on the tenth print medium is completed, the remaining amount of any of the CMY inks becomes zero. Then, a color conversion process using the monochrome monochrome print table SPT is executed, and 10 partial print data of the 11th to 20th sheets are generated. In this case, even though monochrome printing of the same image is performed on 1 to 20 print media, the color of the print result of 4-color monochrome printing on the 1st to 10th print media and 11 to 20 sheets The resulting color of monochrome monochrome printing on the eye print medium can be very different. For this reason, a user may feel uncomfortable.

  On the other hand, in the present embodiment, the color conversion process using the actual correction table ACT is executed, and the tenth partial print data PD4 for the first to tenth sheets are generated. Then, color conversion processing using the monochrome monochrome printing table SPT is executed, and ten partial print data PD5 for the 11th to 20th sheets are generated. As described above, when four-color monochrome printing is to be performed on the first to tenth printing media, the color conversion process, which is a correction process using the actual correction table ACT, is performed. It is possible to approximate the color of the printing result of the four-color monochrome printing for the printing medium of No. 1 to the color of the printing result of the monochrome printing for the 11th to 20th printing media. For this reason, it can suppress giving an uncomfortable feeling to a user.

  The same effect can be obtained when the default correction table DCT is used instead of the actual correction table ACT. However, the actual correction table ACT is data obtained based on the printing result of the test image TI (see FIG. 3) actually executed by the multi-function device 10. For this reason, when the actual correction table ACT is used, the colors of the printing results of two types of monochrome printing can be more approximated.

  Incidentally, it is conceivable to employ a configuration in which the actual correction table ACT is used in place of the four-color monochrome print table FTP in the uncorrected double-sided monochrome print process (see S92 in FIG. 7). However, the 4-color monochrome print table FTP is predetermined by the vendor of the multi-function device 10 so that a high-quality print result can be obtained when 4-color monochrome printing is executed. For this reason, the present embodiment employs a configuration in which the four-color monochrome printing table FTP is used in the uncorrected duplex monochrome printing processing, and as a result, a high-quality printing result can be provided to the user. .

(Correspondence)
The control unit 30 of the multi-function device 10 is an example of a “control device”. CMYK ink and K ink are examples of the “first type color material group” and the “second type color material group”, respectively. CMY ink is an example of “K color materials”. Four-color monochrome printing and single-color monochrome printing are examples of “first type monochrome printing” and “second type monochrome printing”, respectively. The RGB color space and the CMYK color space are examples of the “first color space” and the “second color space”, respectively. The four-color monochrome print table FTP and the single-color monochrome print table SPT are examples of the “first color conversion table” and the “second color conversion table”, respectively.

  In the state where the actual correction table ACT is stored in the memory 34, the actual correction table ACT is an example of “correction data”. In the state where the actual correction table ACT is not stored in the memory 34, the default correction table DCT is , Is an example of “correction data”. The 17 gradations including the gradation “0”, the gradation “16”, and the like are examples of the “plurality of gradations”. The test image data TID is an example of “predetermined image data”. The 17 four-color RGB pixel data group (or 17 single-color RGB pixel data group) included in the test image data TID is an example of “a plurality of reference pixel data”. The test scan data obtained in S14 of FIG. 3 is an example of “first scan data” and “second scan data”. In the test image TI of FIG. 3, 17 pieces of scan pixel data obtained from the four-color area FA and 17 pieces of scan pixel data obtained from the single-color area SA are respectively “a plurality of first scan pixel data”, It is an example of “a plurality of second scan pixel data”. The difference data DD is an example of “difference data”. Each combination data included in the actual correction table ACT is an example of “partial correction data”.

  RGB image data RID1 to RID4 (see FIG. 9) representing the target image to be printed is an example of “target image data”. The situation determined as YES in S80 of FIG. 7 and YES in S90 is an example of the “first situation”. The situation determined as NO in S80 or NO in S90 is an example of the “second situation”. The situation determined as YES in S50 is an example of the “third situation”. In FIG. 9, CMYK image data CID4, CMYK image data CID5, partial print data PD4, and partial print data PD5 are respectively "first specific image data", "second specific image data", and "first part". It is an example of “print data” and “second partial print data”. A set of partial print data PD4 and partial print data PD5 is an example of “first print data”. 1st to 20th print media, 1st to 10th print media, and 11th to 20th print media are “M print media” and “N” respectively. No. print media ”and“ (MN) print media ”. All images printed on both sides of 1st to 10th printing media, all images printed on both sides of 11th to 20th printing media, respectively, are “first part” It is an example of “image” and “second partial image”. The CMYK image data CID3 and the print data PD3 are examples of “third specific image data” and “second print data”, respectively. The print data PD1 is an example of “third print data”.

(Second embodiment; FIG. 10)
In the second embodiment, the actual correction table ACT is not generated in S16 of the actual correction table generation process of FIG. 3, and instead, the difference data DD calculated in S22 of FIG. That is, S24 and S26 of FIGS. 5 and 6 are not executed. Then, as shown in FIG. 10, the CPU 32 executes the following processing in S132 of FIG.

  That is, the CPU 32 first corrects the P-th image data of the acquired RGB image data using the difference data DD, and generates P-th corrected RGB image data. Specifically, when one RGB pixel data constituting the P-th image data is, for example, “16, 16, 16” corresponding to the gradation “16”, the CPU 32 sets “16 , 16, 16 ”and the difference data DD“ 1, 0, −1 ”corresponding to the gradation“ 16 ”are calculated, and the corrected pixel data“ 17, 16, 15 ”is calculated. For example, when one RGB pixel data constituting the P-th image data is a gradation not included in the 17 gradations, a complementary process using two correction pixel data is performed. Then, correction pixel data corresponding to the gradation is calculated. For example, the RGB pixel data “10, 10, 10” includes correction pixel data “0, 0, 0” obtained for the gradation “0” and correction pixel data “17, 16, 15 ”is calculated as corrected pixel data“ 9, 8, 8 ”.

  Next, using the four-color monochrome printing table FPT, the CPU 32 performs color conversion processing on the P-th corrected RGB image data to generate P-th CMYK image data. Then, the CPU 32 executes halftone processing on the P-th CMYK image data to generate P-th partial print data. Thereby, the process of S132 in FIG. 8 ends.

  In the state where the actual correction table generation processing of FIG. 3 is not executed, that is, the state where the difference data DD is not stored in the memory 34, in S132 of FIG. Correction processing using DCT may be executed. Further, instead of the default correction table DCT, a configuration in which default difference data is stored in the memory 34 in advance may be employed. The default difference data is difference data obtained by causing another multi-function device (for example, a so-called master machine) of the same model as the multi-function device 10 to execute the process of FIG. In this configuration, in S132, the CPU 32 can generate the P-th corrected RGB image data using the default difference data when the difference data DD is not stored in the memory 34.

(Effect of the second embodiment)
For example, a situation is assumed in which the corrected double-sided monochrome printing process (see S100 in FIG. 7 and FIG. 8) is executed on 20 print media. Correction processing using the difference data DD is executed, color conversion processing using the four-color monochrome printing table FPT is executed, and ten partial print data of the first to tenth sheets are generated (S132 in FIG. 8). . Then, a color conversion process using the monochrome monochrome printing table SPT is executed, and 10 partial print data of the 11th to 20th sheets are generated (S122). As described above, when four-color monochrome printing is to be executed for the first to tenth printing media, the correction processing using the difference data DD is executed, so that the four colors for the first to tenth printing media are executed. The color of the monochrome print result can be approximated to the color of the monochrome print result for the 11th to 20th print media. For this reason, it can suppress giving an uncomfortable feeling to a user.

(Correspondence)
The difference data DD is an example of “difference data” and “correction data”. Further, the corrected RGB image data generated in S132 of FIG. 8, the CMYK image data generated in S132, and the CMYK image data generated in S122 are “intermediate image data” and “fourth specific image data”, respectively. , Is an example of “fifth specific image data”. Further, the CMYK image data generated in S92 of FIG. 7 is an example of “sixth specific image data”.

  Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above. The modifications of the above embodiment are listed below.

(Modification 1) In the first embodiment, instead of the actual correction table ACT being stored in the memory 34 in S16 of FIG. 3, any one of the coefficient data CD, the difference data DD, and the variation data SD1, SD2 is selected. These data may be stored in the memory 34. In this case, in S132 of FIG. 8, the CPU 32 generates the actual correction table ACT using the data stored in the memory 34. The subsequent processing is the same as S132 in the first embodiment. In the present modification, the above-described data (that is, coefficient data CD, difference data DD, or variation data SD1, SD2) stored in the memory 34 is an example of “correction data”. Further, the process of generating the actual correction table ACT and the color conversion process using the actual correction table ACT are examples of the “correction process”.

(Modification 2) In the second embodiment, the variation data SD1 and SD2 may be stored in the memory 34 instead of the difference data DD being stored in the memory 34 in S16 of FIG. In this case, in S132 of FIG. 8, the CPU 32 generates the difference data DD using the variation data SD1 and SD2 in the memory 34. The subsequent processing is the same as S132 of the second embodiment. In this modification, the variation data SD1 and SD2 are examples of “correction data”. Further, the process of generating the difference data DD and the process of generating the corrected RGB image data using the difference data DD are examples of the “correction process”.

(Modification 3) The “first color material group” may not be four-color ink of CMYK, may be six-color ink (for example, CMYK, light cyan, and light magenta), or eight colors. (For example, the above six colors, gray, and light gray). Further, for example, the multi-function device 10 may execute three-color monochrome printing using CMY ink instead of using K ink instead of executing four-color monochrome printing. In this case, the CMY three-color ink is an example of the “first color material group”. Further, the “second color material group” is not limited to one ink of K, and may be ink of two or more colors (for example, K and gray). The “first type of color material group” and the “second type of color material group” are not limited to ink, and may be other color materials (for example, toner) used for printing.

(Modification 4) In each of the embodiments described above, the multi-function device 10 executes the four-color monochrome printing first when executing the corrected double-side monochrome printing process (see S100 in FIG. 7 and FIG. 8), and is monochrome. Perform monochrome printing later. Instead of this, the multi-function device 10 may execute monochromatic monochrome printing first and 4-color monochrome printing later. For example, the multi-function device 10 calculates the number of printed sheets K where the remaining amount of any CMY ink is expected to be zero based on the remaining amount of CMY ink, and calculates the calculated number of printed sheets from the planned number of printed sheets L. Monochromatic monochrome printing on (L−K) print media from which K has been subtracted may be executed first, and 4-color monochrome printing on the remaining K print media may be executed later. Even with this configuration, the user can be prevented from feeling uncomfortable. Generally speaking, the “print data generation unit” may generate the first partial print data first and the second partial print data later, as in the above embodiment. As in the modification, the second partial print data may be generated first, and the first partial print data may be generated later. Note that the multi-function device 10 performs monochrome monochrome printing when the remaining amount of K ink is equal to or less than the predetermined amount Th, and then performs monochrome printing using CMY ink when the remaining amount of K ink becomes zero. Printing (that is, three-color monochrome printing) may be performed.

(Modification 5) The process of S90 in FIG. 7 may be omitted. In this case, the situation of YES in S80 and the situation of NO in S80 are examples of “first situation” and “second situation”, respectively. Further, the process of S80 in FIG. 7 may be omitted. In this case, the situation of YES in S90 and the situation of NO in S90 are examples of “first situation” and “second situation”, respectively.

(Modification 6) In each of the above embodiments, in S14 of FIG. 3, the multi-function device 10 displays the test image TI including both the result of four-color monochrome printing and the result of single-color monochrome printing on one print medium. And scan the print medium to obtain test scan data. Instead, the multi-function device 10 prints the first test image including the results of the four-color monochrome printing on one print medium, and then the second test image including the results of the single-color monochrome printing. It is also possible to print on a single print medium. Then, the multi-function device 10 may scan the former print medium to obtain first test scan data, and may calculate the variation data SD1 (see FIG. 4) using the first test scan data. . Further, the multi-function device 10 may scan the latter print medium to obtain the second test scan data, and calculate the variation data SD2 (see FIG. 4) using the second test scan data. . In the present modification, the first test scan data and the second test scan data are examples of “first scan data” and “second scan data”, respectively.

(Modification 7) In each of the above embodiments, correction data for reducing the difference between the variation data SD1 and SD2 (for example, the actual correction table ACT of the first embodiment (see FIG. 6), the difference of the second embodiment) By using data DD (see FIG. 10)), the results of two types of monochrome printing are approximated. Instead of this, for example, the value of the scan pixel data obtained from the four-color area FA (for example, “36, 35, 30” corresponding to the gradation “0” in S20 of FIG. 4) and the single-color area SA are obtained. Correction data for reducing the difference between the value of the scan pixel data (for example, “15, 14, 7” corresponding to the gradation “0”) may be used. In the above example, for example, the correction is performed so that the R value “36” approaches “15”, the G value “35” approaches “14”, and the B value “30” approaches “7”. Data is generated. According to this modification, not only the colors of two types of monochrome printing can be approximated, but also the densities of the two types of monochrome printing can be approximated. Generally speaking, the “correction data” may be data that approximates the result of the first type monochrome printing to the result of the second type monochrome printing. Note that when correction data for reducing the difference between the variation data SD1 and SD2 is used as in the above embodiments, the amount of ink used can be kept to a minimum. It is possible to suppress the ink from adhering to the members inside the path.

(Modification 8) The CPU 32 of the multi-function device 10 does not have to execute the processes shown in FIGS. Instead, for example, the PC 50 includes a driver program for the multi-function device 10, and the driver program may include each table FPT, SPT, CPT, DCT and test image data TID. And PC50 may perform each processing of Drawing 3 and Drawing 7 according to the driver program concerned. However, when executing the processing of FIG. 3, the PC 50 supplies the print data to the multi-function device 10 in S12 and causes the multi-function device 10 to print the test image TI. In S14, the PC 50 acquires test scan data from the multi-function device 10 without executing scan processing. Further, when executing the processing of FIG. 7, the PC 50 supplies the print data to the multi-function device 10 in S52, S72, S92, and S100, and causes the multi-function device 10 to print the target image. In this modification, the PC 50 and the multi-function device 10 are examples of a “control device” and a “print execution unit”, respectively.

(Modification 9) In the above embodiment, the CPU 32 of the multi-function device 10 executes the program PGM (that is, software), thereby realizing the processes shown in FIGS. Instead, at least one of the processes in FIGS. 3 and 7 may be realized by hardware such as a logic circuit.

  The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology illustrated in the present specification or the drawings achieves a plurality of objects at the same time, and has technical utility by achieving one of the objects.

  2: communication system, 10: multi-function device, 12: operation unit, 14: display unit, 16: print execution unit, 18C, 18M, 18Y, 18K: ink cartridge, 20C, 20M, 20Y, 20K: remaining amount sensor, 22: Scan execution unit, 24: Communication interface, 30: Control unit, 32: CPU, 34: Memory, RGM: Program, FPT: 4-color monochrome printing table, SPT: Monochromatic monochrome printing table, CPT: Color printing table, DCT : Default correction table, ACT: Actual correction table, TID: Test image data, TI: Test image, SD1, SD2: Variation data, DD: Difference data, CD: Coefficient data, RID1-RID4: Image data, CID1-CID5: CMYK image data, PD1 to PD3: print data, PD4, PD : Partial print data

Claims (12)

To control a print execution unit capable of executing the first type of monochrome printing using the first type of color material group and capable of executing the second type of monochrome printing using the second type of color material group. A control device of
A memory for storing correction data for approximating the result of the first type monochrome printing to the result of the second type monochrome printing;
A target image data acquisition unit that acquires target image data representing a target image to be printed;
A print data generation unit that generates print data using the target image data;
A supply unit that supplies the print data to the print execution unit,
The print data generation unit
In the first situation, first print data including first partial print data and second partial print data is generated using the target image data,
In a second situation different from the first situation, second print data is generated using the target image data,
The print data generation unit
In the first situation, a correction process using the correction data is performed on the target image data, and the first type monochrome of the first partial image which is a part of the target image. The first partial print data for printing is generated, and the correction process using the correction data is not performed on the target image data, and the first partial print data is the remaining part of the target image. Generating the second partial print data for the second type monochrome printing of two partial images;
In the second situation, without performing the correction process using the correction data on the target image data, the second for all the first type monochrome printing of the target image. A control device that generates print data. The control device further includes:
Any of the K color materials included in the first type of color material group (where K is an integer of 1 or more) and not included in the second type of color material group A determination unit that determines whether or not the remaining amount is less than or equal to a predetermined value;
In the first situation where it is determined that the remaining amount of any of the K color materials is equal to or less than the predetermined value,
The print data generation unit generates the first partial print data before any remaining amount of the K color materials becomes zero,
The supply unit supplies the first partial print data to the print execution unit before any remaining amount of the K color materials becomes zero,
The print data generation unit generates the second partial print data after the remaining amount of any of the K color materials becomes zero,
The supply unit supplies the second partial print data to the print execution unit after the remaining amount of any of the K color materials becomes zero,
2. The print data generation unit generates the second print data in the second situation in which it is determined that none of the remaining amount of the K color materials is equal to or less than the predetermined value. Control device.   The said supply part does not supply the said 2nd partial print data to the said print execution part, after the residual amount of the color material contained in the said 2nd type color material group becomes zero. Control device. The print data generation unit
In the first situation in which the target image is to be printed on M (M is an integer of 2 or more) print media, printing is performed on N (N is an integer greater than or equal to 1 and less than M) print media. The first partial print data for the first type monochrome printing of the first partial image to be printed, and the second partial image to be printed on (MN) print media. Generating the first print data including the second partial print data for the second type monochrome printing,
In the second situation where the target image is to be printed only on one print medium, for all the first type monochrome printing of the target image to be printed only on the one print medium The control device according to claim 1, wherein the control unit generates the second print data.   The print data generation unit includes K color materials (K is an integer equal to or greater than 1) included in the first type of color material group, and is not included in the second type of color material group. The control device according to any one of claims 1 to 4, wherein the print data is not generated when any remaining amount of the individual color materials is zero. The print data generation unit
In the first situation where the target image is to be printed on both sides of a print medium, the first print data including the first partial print data and the second partial print data is generated,
In the third situation where the target image is to be printed only on one side of the print medium, the correction process using the correction data is not performed on the target image data, and all of the target images are The control device according to claim 1, wherein the control device generates third print data for the second type of monochrome printing. The first type of color material group includes a chromatic color material,
The control device according to any one of claims 1 to 6, wherein the second type of color material group does not include a chromatic color material but includes an achromatic color material. The control device further includes:
First scan data obtained by scanning a print result of the first type monochrome printing executed by the print execution unit according to predetermined image data, and executed by the print execution unit according to the predetermined image data A scan data acquisition unit for acquiring second scan data obtained by scanning a print result of the second type monochrome printing to be performed;
A correction data generation unit that generates the correction data using the first scan data and the second scan data, and stores the correction data in the memory;
The control apparatus according to claim 1, comprising: The predetermined image data includes a plurality of reference pixel data corresponding to a plurality of gradations,
The first scan data is a plurality of first scan pixel data obtained by scanning a print result of the first type monochrome printing according to the plurality of reference pixel data, Including a plurality of first scan pixel data corresponding to a plurality of gradations;
The second scan data is a plurality of second scan pixel data obtained by scanning a print result of the second type monochrome printing according to the plurality of reference pixel data, A plurality of second scan pixel data corresponding to a plurality of gradations;
For each of the plurality of gradations, the correction data is represented by the color represented by the first scan pixel data corresponding to the gradation and the second scan pixel data corresponding to the gradation. The control device according to claim 8, comprising partial correction data obtained using difference data indicating a difference from a color. The memory further includes
A first color conversion table to be used for generating print data for the first type of monochrome printing, wherein a pixel value in the first color space is changed to a pixel value in the second color space. The first color conversion table for converting to
A second color conversion table to be used for generating print data for the second type of monochrome printing, wherein pixel values in the first color space are converted into pixels in the second color space. The second color conversion table for converting to a value;
Store
The correction data includes a change table obtained by changing the first color conversion table in order to approximate the result of the first type monochrome print to the result of the second type monochrome print,
The print data generation unit, in the first situation,
Using the change table, the correction process for converting the target image data represented by the pixel values in the first color space is executed, and the pixel values in the second color space are used. Generating first specific image data to be represented;
Generating the first partial print data using the first specific image data;
The target image data represented by each pixel value in the first color space is converted into the second color space by using the second color conversion table without executing the correction process. Converted into second specific image data represented by each pixel value,
Generating the second partial print data using the second specific image data;
In the second situation, the print data generation unit
Without executing the correction process, the target image data represented by each pixel value in the first color space is converted into the second color space by using the first color conversion table. Converted into third specific image data represented by each pixel value,
The control device according to claim 1, wherein the second print data is generated using the third specific image data. The memory further includes
A first color conversion table to be used for generating print data for the first type of monochrome printing, wherein a pixel value in the first color space is changed to a pixel value in the second color space. The first color conversion table for converting to
A second color conversion table to be used for generating print data for the second type of monochrome printing, wherein pixel values in the first color space are converted into pixels in the second color space. The second color conversion table for converting to a value;
Store
The correction data is obtained by using pixel values in the first color space as pixels in the first color space in order to approximate the result of the first type monochrome printing to the result of the second type monochrome printing. Including a correction table for correcting to values,
The print data generation unit, in the first situation,
Using the correction table, the correction processing for correcting the target image data expressed by the pixel values in the first color space is executed, and the pixel values in the first color space are used. Generate intermediate image data to be expressed,
Using the first color conversion table to convert the intermediate image data represented by each pixel value in the first color space to generate fourth specific image data;
Generating the first partial print data using the fourth specific image data;
The target image data represented by each pixel value in the first color space is converted into the second color space by using the second color conversion table without executing the correction process. Converted into fifth specific image data represented by each pixel value;
Generating the second partial print data using the fifth specific image data;
In the second situation, the print data generation unit
Without executing the correction process, the target image data represented by each pixel value in the first color space is converted into the second color space by using the first color conversion table. Converted into sixth specific image data represented by each pixel value;
10. The control device according to claim 1, wherein the second print data is generated using the sixth specific image data. 11. To control a print execution unit capable of executing the first type of monochrome printing using the first type of color material group and capable of executing the second type of monochrome printing using the second type of color material group. A computer program for a control device of
The controller is
A processor, and a memory for storing correction data for approximating the result of the first type monochrome printing to the result of the second type monochrome printing,
The computer program causes the processor to execute the following processes:
Target image data acquisition processing for acquiring target image data representing a target image to be printed;
Print data generation processing for generating print data using the target image data;
Supplying the print data to the print execution unit, and
In the print data generation process,
In the first situation, first print data including first partial print data and second partial print data is generated using the target image data,
In a second situation different from the first situation, second print data is generated using the target image data,
In the print data generation process,
In the first situation, a correction process using the correction data is performed on the target image data, and the first type monochrome of the first partial image which is a part of the target image. The first partial print data for printing is generated, and the correction process using the correction data is not performed on the target image data, and the first partial print data is the remaining part of the target image. Generating the second partial print data for the second type monochrome printing of two partial images;
In the second situation, without performing the correction process using the correction data on the target image data, the second for all the first type monochrome printing of the target image. A computer program that generates print data.

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