JP4826568B2 - Color conversion apparatus, color conversion program, and color conversion method - Google Patents

Description

  The present invention relates to a color conversion device, a color conversion program, and a color conversion method.

  There is known an image forming apparatus capable of forming an image by ejecting ink onto a recording sheet. There are two types of inks, pigment inks and dye inks. Pigment inks have lower fixability than dye inks. For this reason, for example, when printing the back side of double-sided printing, there is a problem that the paper transport roller contacts the pigment ink printed on the front surface when transporting the paper, and the pigment ink adheres to the paper transport roller.

  Black ink (hereinafter referred to as K ink) is often composed of pigment ink, and the above disadvantages are likely to occur. Therefore, the K ink density (use amount) is adjusted to an appropriate value according to the type of recording paper. It is important to.

  Here, the fixing property of the ink is not only different depending on the type of recording paper such as plain paper, special paper, glossy paper, and varies depending on, for example, the manufacturer or the manufacturing process among the plain paper. Therefore, if a color table with a small amount of K ink used is created on the basis of the recording sheet with the lowest fixability and is used for all the recording sheets, any recording sheet is used. While the problem of fixability is solved, there is another inconvenience that sufficient image quality (hue) cannot be obtained.

  As another method, a method of creating a color table storing the optimum black component value for each type of recording paper is also conceivable, but in this way, a table is created for all possible recording papers. It must be created and stored, and the man-hours for creating the color table and the memory usage amount become enormous, which is not realistic.

Therefore, Patent Document 1 discloses a technique for reducing the color density (that is, reducing the amount of ink used) when performing double-sided printing as compared to when performing single-sided printing. In this way, the ejected ink is absorbed by the recording paper, and even when double-sided printing is performed, the already printed surface is prevented from soiling the paper transport roller and the like.
JP 2007-118238 A

  However, Patent Document 1 is concerned only with double-sided printing, and other problems that may occur on recording paper with low ink fixing properties are not improved at all. For example, even in the case of single-sided printing, if a recording paper with low ink fixability is used, there is a problem that an undried printed matter is rubbed with a user's finger or the like.

  The present invention has been made to solve the above-described problems, and can reduce the amount of memory used, and an achromatic color component value included in an output value can be an appropriate value corresponding to the type of recording medium. It is an object of the present invention to provide a color conversion device, a color conversion program, and a color conversion method.

In order to achieve this object, the color conversion device according to aspect 1 uses an achromatic color component value and an achromatic color component value to form an image on a recording medium using an achromatic color material and a chromatic color material. The first color conversion means for converting the input value into the first color data including the chromatic color component value, and the achromatic color component value for the same input value. Second color conversion means for converting the input value into second color data including the chromatic color component value and the achromatic color component value such that the input value is equal to or greater than the achromatic color component value included in the first color data; An adjustment value determining unit that determines an adjustment value according to the type of recording medium to be image-formed, and a first color converted by the first color conversion unit according to the adjustment value determined by the adjustment value determining unit Weights the data and the second color data converted by the second color conversion means Characterized in that it comprises an output value obtaining means for obtaining an output value by Kesuru.

The color conversion device according to aspect 2 is the color conversion device according to aspect 1, wherein the first color data includes a gray component determination unit that determines a gray component based on the input value, and an achromatic color component value corresponding to the same input value. Second relation storage means for storing a relationship between a correction value of the chromatic color component value corresponding to the gray component and a correction value of the achromatic color component value, which is predetermined so as to be equal to or higher than the achromatic color component value. The second color conversion means determines a chromatic color component value obtained by converting the input value according to a relation stored in the second relation storage means, and the achromatic color component correction value. The input value is converted into second color data by performing correction using a correction value of the value.

The color conversion device according to aspect 3 is the color conversion device according to aspect 2, further comprising first relationship storage means for storing a relationship between an input value and the chromatic color component value, wherein the first color conversion means is the first color conversion means. Chromatic color component conversion means for converting the input value into a chromatic color component value of the first color data according to the relationship stored in the relationship storage means, and the second color conversion means is provided by the chromatic color component conversion means. A value obtained by correcting the converted chromatic color component value using the correction value of the chromatic color component value determined according to the relationship stored in the second relationship storage means is used as the chromatic color component of the second color data. It is characterized by a value.

The color conversion device according to aspect 4 is the color conversion device according to aspect 3, wherein the first color conversion unit adds a predetermined achromatic color component value to the chromatic color component value acquired by the chromatic color component value acquisition unit. The first color data generating means for generating the first color data is provided.

The color conversion device according to aspect 5 is the color conversion device according to aspect 1, in which third relationship storage means for storing the relationship between the achromatic color component value and the chromatic color component value for the input value, and the achromatic color component for the input value A fourth relationship in which an achromatic color component value for the same input value is greater than or equal to an achromatic color component value obtained from a relationship stored in the third relationship storage means. Storage means, wherein the first color conversion means converts the input value into the first color data in accordance with the relationship stored in the third relationship storage means, and the second color conversion means The input value is converted into the second color data in accordance with the relationship stored in the fourth relationship storage means.

The color conversion apparatus according to the sixth aspect includes an input value as an output value including an achromatic color component value and a chromatic color component value in order to form an image on a recording medium using an achromatic color material and a chromatic color material. A fifth relationship storage means for storing the relationship between the achromatic color component value and the chromatic color component value with respect to the input value, and the relationship between the achromatic color component value and the chromatic color component value with respect to the input value And a sixth relation storage means for which the achromatic color component value for the same input value is equal to or greater than the achromatic color component value obtained from the relation stored in the fifth relation storage means, and recording of the image formation target An adjustment value determining unit that determines an adjustment value according to the type of medium, and an achromatic color component value and a chromatic color component stored in the fifth relation storage unit according to the adjustment value determined by the adjustment value determining unit Value and achromatic color stored in the sixth relation storage means By weighting the component value and the chromatic color component value, the relationship creating means for creating the relationship between the input value, the achromatic color component value, and the chromatic color component value, and the relationship created by the relationship creating means And output value acquisition means for converting the input value and acquiring the output value.

In the color conversion device according to the seventh aspect, in order to form an image on a recording medium using an achromatic color material and a chromatic color material, an input value is an output value including an achromatic color component value and a chromatic color component value. A seventh color converting means for converting the input value into first color data that includes the chromatic color component value and does not include the achromatic color component value; and the input value is converted to the chromatic color component value. An eighth color conversion unit that converts the second color data including the achromatic color component value, an adjustment value determination unit that determines an adjustment value according to the type of the recording medium to be image formed, and the adjustment value determination unit. Output for obtaining an output value by weighting the first color data converted by the seventh color conversion means and the second color data converted by the eighth color conversion means in accordance with the determined adjustment value And a value acquisition means.

The color conversion device according to aspect 8 is the color conversion device according to any one of aspects 1 to 7, characterized in that the achromatic color material is composed of pigment ink.

The color conversion program according to the ninth aspect includes an input value as an output value including an achromatic color component value and a chromatic color component value in order to form an image on a recording medium using an achromatic color material and a chromatic color material. A program for causing a computer to execute the process of converting the input value to the first color conversion means for converting the input value into the first color data including the chromatic color component value. A second color for converting the input value into second color data including the chromatic color component value and the achromatic color component value so that the achromatic color component value is equal to or greater than the achromatic color component value included in the first color data. Conversion means, adjustment value determination means for determining an adjustment value according to the type of recording medium to be image formed, and conversion by the first color conversion means according to the adjustment value determined by the adjustment value determination means. The first color data and the second color change Wherein the function as the output value acquisition means for acquiring the output value by weighting the second color data converted by means.

The color conversion program according to the tenth aspect includes an input value as an output value including an achromatic color component value and a chromatic color component value in order to form an image on a recording medium using an achromatic color material and a chromatic color material. A program for causing a computer to execute the process of converting the input value into a fifth relation storage means for storing a relationship between an achromatic color component value and a chromatic color component value with respect to the input value; The relationship between the achromatic color component value and the chromatic color component value is stored, and the achromatic color component value for the same input value is greater than or equal to the achromatic color component value obtained from the relationship stored in the fifth relationship storage means. A sixth relation storage means, the computer according to the adjustment value determined by the adjustment value determination means, the adjustment value determination means for determining the adjustment value according to the type of the recording medium of the image formation target, Above 5. The input value and the achromatic color are weighted by weighting the achromatic color component value and the chromatic color component value stored in the relationship storage means and the achromatic color component value and the chromatic color component value stored in the sixth relationship storage means. A function for creating a relationship between the component value and the chromatic color component value, and a function for obtaining an output value by converting the input value according to the relationship created by the relationship creating unit. It is characterized by.

In the color conversion method of aspect 11 , in order to form an image on a recording medium using an achromatic color material and a chromatic color material, an input value is an output value including an achromatic color component value and a chromatic color component value. A first color conversion step of converting an input value into first color data including the chromatic color component value, and an achromatic color component value for the same input value included in the first color data A second color conversion step of converting the input value into second color data including the chromatic color component value and the achromatic color component value so as to be equal to or higher than the achromatic color component value, and the type of recording medium to be image-formed An adjustment value determination step for determining an adjustment value according to the first color data and the second color conversion step converted by the first color conversion step according to the adjustment value determined by the adjustment value determination step The output value by weighting the second color data converted by Characterized in that it comprises an output value acquisition step of acquiring.

In the color conversion method of aspect 12 , in order to form an image on a recording medium using an achromatic color material and a chromatic color material, an input value is an output value including an achromatic color component value and a chromatic color component value. An adjustment value determining step for determining an adjustment value according to the type of recording medium to be image-formed, and a relationship between an achromatic color component value and a chromatic color component value for the input value is stored. 5 relationship storage means for storing the relationship between the achromatic color component value and the chromatic color component value for the input value, and the achromatic color component value for the same input value is stored in the fifth relationship storage means. A sixth relationship storage means that is greater than or equal to the achromatic color component value obtained from the relationship, and the achromatic color component value stored in the fifth relation storage means and the existence according to the adjustment value determined in the adjustment value determination step. Colored component value and stored in the sixth relation storage means The relationship creation step of creating a relationship between the input value and the achromatic color component value and the chromatic color component value by weighting the achromatic color component value and the chromatic color component value, and the relationship created by the relationship creation step And an output value acquisition step of acquiring the output value by converting the input value.

According to the color conversion device described in the aspect 1, the adjustment value determining unit determines the adjustment value according to the type of the recording medium to be image formed, and according to the determined adjustment value, the first color data, Since the output value is obtained by weighting the second color data in which the achromatic color component value for the same input value is greater than or equal to the achromatic color component value included in the first color data, the output value is not included. There is an effect that the color component value can be set to an appropriate value according to the type of the recording medium. In addition, there is an effect that the memory usage can be suppressed as compared with the case where the optimum achromatic color component value is stored for each type of storage medium.

  Here, “type of recording medium” refers to a recording medium classified according to the degree of ink fixability. Therefore, for example, even if the recording medium is generally classified as plain paper, the recording medium having different ink fixing properties due to differences in the manufacturer and manufacturing process is different in the present invention. It may be a recording medium.

According to the color conversion device described in aspect 2, in addition to the effect produced by the color conversion device described in aspect 1, the second correction value of the chromatic color component value and the correction of the achromatic color component value corresponding to the gray component are added. Since the color data is weighted according to the type of the recording medium and reflected in the output value, there is an effect that it is possible to suppress the deterioration of the image quality (color tone) while suppressing the memory usage amount according to the gray component.

According to the color conversion device described in aspect 3, in addition to the effects produced by the color conversion device described in aspect 2, the chromatic color component values converted by the chromatic color component conversion means are both the first color data and the second color data. This has the effect that the processing efficiency is good. Further, since an appropriate achromatic color component value corresponding to the type of the recording medium is obtained from the two relations of the relation stored in the first relation storage means and the relation stored in the second relation storage means, the recording is performed. There is an effect that the memory usage can be suppressed as compared with the case where the optimum achromatic color component value is stored for each type of medium.

According to the color conversion device described in aspect 4, in addition to the effect produced by the color conversion device described in aspect 3, the first color conversion unit adds a predetermined value to the chromatic color component value acquired by the chromatic color component value acquisition unit. Since the first color data to which the chrominance component value is added is generated, the first color data can be easily generated, and the processing load is small.

  Preferably, the “predetermined achromatic color component value” is a value equal to or less than a minimum value of a range that the achromatic color component value determined according to the relationship stored in the second relationship storage means can take. In this way, it is possible to easily generate the first color data such that the achromatic color component value of the second color data for the same input value is always the achromatic color component value of the first color data.

According to the color conversion device described in aspect 5, in addition to the effects achieved by the color conversion device described in aspect 1, there are two relations: a relationship stored in the third relationship storage unit and a relationship stored in the fourth relationship storage unit Since an appropriate achromatic color component value corresponding to the type of recording medium is obtained from the relationship, the amount of memory used can be suppressed as compared with the case of storing the optimal achromatic color component value for each type of recording medium. There is an effect.

According to the color conversion apparatus described in the sixth aspect , the achromatic color component value and the chromatic color component value stored in the fifth relation storage unit and the sixth relation storage unit are stored in accordance with the adjustment value corresponding to the type of the recording medium. By weighting the achromatic color component value and the chromatic color component value, a relationship between the input value and the achromatic color component value and the chromatic color component value is created, and the input value is determined according to the created relationship. Since the output value is obtained after conversion, an appropriate value corresponding to the type of the recording medium is obtained from the two relationships, the relationship stored in the fifth relationship storage means and the relationship stored in the sixth relationship storage means. A color component value is obtained. Therefore, there is an effect that the memory usage can be suppressed as compared with the case where the optimum achromatic color component value is stored for each type of recording medium.

According to the color conversion device described in aspect 7, the adjustment value determining unit determines the adjustment value according to the type of the recording medium to be image formed, and includes the achromatic color component value according to the determined adjustment value. Since the output value is obtained by weighting the first color data that is not present and the second color data including the chromatic color component value and the achromatic color component value, the achromatic color component value included in the output value is recorded. There is an effect that an appropriate value can be set according to the type of the medium. In addition, there is an effect that the memory usage can be suppressed as compared with the case where the optimum achromatic color component value is stored for each type of storage medium.

According to the color conversion device described in aspect 8, in addition to the effects exhibited by the color conversion device according to any one of aspects 1 to 7, the achromatic color material is composed of pigment ink, so that it can be fixed to a recording medium. However, the achromatic color component value corresponding to the amount of pigment ink used is lower than that of dye ink is an appropriate value according to the type of recording medium, and various inconveniences caused by the fact that the recording paper is not fixed to the ink are suppressed. Is done.

  Here, the “adjustment value determination means” described in the claims and the specification determines different adjustment values for three or more types of recording media. In this way, it is possible to cope with three or more types of recording media while suppressing the memory usage.

According to the color conversion program aspect 9, can be made to function similarly to the color conversion apparatus of a computer embodiment 1 described, the same effect as the color conversion device of embodiment 1, wherein is obtained.

According to the color conversion program aspect 10, wherein can function similarly to the color conversion device of the computer aspect 6, wherein, the same effect as the color conversion device of Embodiment 6 described is obtained.

According to the color conversion method described in aspect 11, the same effects as the color conversion apparatus described in aspect 1 can be obtained.

According to the color conversion method described in aspect 12, the same effects as the color conversion method described in aspect 6 can be obtained.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a connection diagram showing a connection relationship between a personal computer 10 (hereinafter referred to as a PC 10), which is a first embodiment of the color conversion apparatus of the present invention, and an image forming apparatus 40.

  The personal computer 10 according to the first embodiment converts input color data RGB (an example of an input value) including R (red), G (green), and B (blue) color component values into C (cyan) M (magenta) Y ( A device that converts output color data CMYK (an example of an output value) composed of each color component value of yellow (K) (black), and in particular, a black component value K (an example of an achromatic component) included in the output color data CMYK. Can be set to an appropriate value according to the type of recording paper (an example of a recording medium), and the amount of memory used can be suppressed.

  The PC 10 transfers print data including output color data CMYK obtained by converting the input color data RGB to the image forming apparatus 40. The image forming apparatus 40 is configured by a so-called ink jet printer that forms an image by ejecting inks of CMYK colors onto recording paper based on print data output from the PC 10. The K ink used in the image forming apparatus 40 is composed of pigment ink, and the other chromatic CMY inks are composed of dye ink. Pigment inks have a lower fixability on recording paper than dye inks. Therefore, if the K ink ejected onto the recording paper is excessive, the ink does not fix on the recording paper, causing various inconveniences such as rubbing by the user's finger or adhering to other members and soiling the members. Occurs. The fixing property of the ink varies depending on the type of recording paper, but according to the PC 10 of the first embodiment, the black component value K corresponding to the amount of K ink used corresponds to the type of recording paper to be image-formed. Therefore, the inconvenience as described above is suppressed. The K ink used in the image forming apparatus 40 corresponds to the achromatic color material described in the claims, and the C ink, the M ink, and the Y ink are the chromatic color materials described in the claims. Equivalent to.

  An opening 42 is provided on the front surface of the main body of the image forming apparatus 40 and the interior is partitioned vertically. A paper feed cassette 43 capable of stacking and storing a plurality of recording sheets is inserted below the opening 42. The upper side of the opening 42 is a paper discharge unit 44 for discharging recorded recording paper, and the recorded recording paper is discharged in the direction of arrow A.

  Above the opening 42, there are provided an operation key 45 and a liquid crystal display device 46 (hereinafter referred to as an LCD 46) for displaying a menu, an operation procedure, and the status of a process being executed. The user can perform operations such as power on / off and switching of each function by pressing the operation key 45.

  A memory card slot 47 for detachably mounting a memory card is provided on the front surface of the opening 42 and below the operation key 45. One end of the USB cable 60 is connected to the USB interface 48 (see FIG. 2) provided on the back surface of the opening 42. The other end of the USB cable 60 is connected to the USB interface 16 of the PC 10 (see FIG. 2), so that the image forming apparatus 40 and the PC 10 can perform data communication with each other via the USB cable 60. It is configured as follows.

  Next, an electrical configuration of the PC 10 and the image forming apparatus 40 will be described with reference to FIG. FIG. 2 is a block diagram showing an electrical configuration of the PC 10 and the image forming apparatus 40. The PC 10 mainly includes a CPU 11, a ROM 12, a RAM 13, a hard disk drive 14 (hereinafter referred to as an HDD 14), a USB interface 16, an input device 17, and a display device 18, which are connected to each other via a bus line 20. ing.

  The CPU 11 controls each unit connected by the bus line 20 according to fixed values and programs stored in the ROM 12, RAM 13, and HDD 14. The ROM 12 is a memory in which a program for controlling the operation of the PC 10 is stored, and the RAM 13 is a readable / writable memory for temporarily storing data necessary for the processing of the CPU 11.

The HDD 14 is a hard disk drive, and stores (installs) a printer driver 141 for executing a page printing process (S1) described later with reference to FIGS. The HDD 14 further includes a lookup table 142, a GCR (Gray-Component).
(Replacement) table 143 and adjustment parameter table 144 are stored.

  The look-up table 142 stores input color data RGB and CMYK color component values in association with each other in order to match the display color on the display device 18 of the PC 10 with the color formed on the image forming device 40. It is. By referring to the lookup table 142, the input color data RGB is converted into primary conversion data C1M1Y1. The minimum value among the chromatic color component values C1, M1, and Y1 included in the primary conversion data C1M1Y1 is referred to as minK.

  The GCR table 143 is a table that is referred to in order to determine correction values (ΔC, ΔM, ΔY, ΔK) corresponding to the gray component minK.

  The GCR table 143 will be described with reference to FIG. FIG. 3 shows an example of the GCR table. As shown in FIG. 3, the GCR table 143 stores gray component minK as a variable and stores CMYK correction values (ΔC, ΔM, ΔY, ΔK) corresponding to the gray component. The correction values (ΔC, ΔM, ΔY) correspond to an example of “correction value of chromatic color component value” described in the claims, and the correction value ΔK is “achromatic color” described in the claims. It corresponds to “correction value of component value”.

Using this gray component minK and the correction values (ΔC, ΔM, ΔY, ΔK), the primary conversion data C1M1Y1 is corrected as shown in the following equations (2) to (5), whereby the input color data RGB is converted into the first color data RGB. Two-color data C2M2Y2K2 can be converted. The following formulas (2) to (5) are examples of calculation formulas for obtaining the second color data C2M2Y2K2. As long as the second color data C2M2Y2K2 is obtained using the correction values (ΔC, ΔM, ΔY, ΔK), the calculation may be different from the following formulas (2) to (5).
C2 = C1-minK + ΔC (2)
M2 = M1-minK + ΔM (3)
Y2 = Y1-minK + ΔY (4)
K2 = ΔK (5)
In the first embodiment, the data obtained by adding the black component value K1 having the value “0” to the primary conversion data C1M1Y1 obtained by converting the input color data RGB is referred to as the first color data C1M1Y1K1. Called. On the other hand, data obtained by converting the input color data RGB using the gray component minK and the correction values (ΔC, ΔM, ΔY, ΔK) will be referred to as second color data C2M2Y2K2 in the first embodiment. K2 included in the second color data C2M2Y2K2 is equal to ΔK (see the above formula (5)).

  As shown in FIG. 3, ΔK is a value equal to or greater than 0, and when minK exceeds 128, ΔK is a value that increases as minK increases. Therefore, when the first color data C1M1Y1K1 obtained by converting the same input color data and the second color data C2M2Y2K2 are compared, the relationship of K1 ≧ K2 is always established. That is, the black component value K2 included in the second color data C2M2Y2K2 is always greater than or equal to the black component value K1 included in the first color data C1M1Y1K1.

In the first embodiment, the first color data C1M1Y1K1 having a relatively small black component value and the second color data C2M2Y2K2 having a relatively large black component value thus obtained will be described later. According to the adjustment parameter a, for example, the output color data CMYK including the black component value K appropriate for the type of recording paper can be obtained by weighting according to the arithmetic expression shown in the following expression (6).
CMYK = C1M1Y1K1 * a + C2M2Y2K2 * (1-a) (6)
Returning to FIG. The adjustment parameter table 144 is a table that stores the recording paper type and the adjustment parameter a in association with each other.

  The adjustment parameter table 144 will be described with reference to FIG. FIG. 4 is a diagram schematically illustrating an example of the adjustment parameter table 144. Among the types of recording paper illustrated in FIG. 4, “exclusive paper” is a paper on which a special coating is applied in order to obtain a high-quality image, and has the best ink fixability. On the other hand, the paper 1, the paper 2, and the paper 3 are all plain papers and have different ink fixing properties due to differences in manufacturing processes and manufacturers.

  Here, the “ink fixability” refers to, for example, placing a transfer paper for measurement on a printing surface to be measured after printing, rubbing the printing surface and the transfer paper with a predetermined pressure, and placing the printing paper on the printing surface. It can be measured by measuring the transfer (brightness) of the ink onto the transfer paper. In the case of a recording paper with low ink fixing properties, the amount of ink transferred from the printing surface to the transfer paper is large, and the lightness is low. On the other hand, in the case of a recording sheet having high ink fixing properties, the amount of ink transferred from the printing surface to the transfer sheet is small, and therefore the brightness is increased.

  This “ink fixing property” is not only different for each recording sheet, but also depends on whether the ink is pigment ink or dye ink. In the present embodiment, description will be made assuming that the adjustment parameter a is set on the basis of the fixability of K ink composed of pigment ink.

  As the adjustment parameter a, a smaller value is associated with a recording sheet having higher K ink fixability. As a result, the weight of the first color data C1M1Y1K1 is small, and the weight of the second color data C2M2Y2K2 having a larger black component value than that of the first color data C1M1Y1K1 is increased. For example, since dedicated paper has high ink fixability, for example, “0.0” is stored as the adjustment parameter a. Accordingly, the weight of the first color data C1M1Y1K1 is set to “0” and the weight of the second color data C2M2Y2K2 is set to “1” (see the above formula (6)), so that a high black component value is obtained. As a result, the use density of the K ink is increased to the limit, and a high-quality image can be formed by taking advantage of the characteristics of the recording paper.

  On the other hand, a larger value is associated with the adjustment parameter a for recording sheets with lower ink fixing properties. For example, since the paper 1 has low ink fixability, for example, “1.0” is stored as the adjustment parameter a. Accordingly, the weight of the first color data C1M1Y1K1 is set to “1”, and the weight of the second color data C2M2Y2K2 is set to “0” (see the above expression (6)). Therefore, the output color data CMYK having a black component value of 0. Is obtained. As described above, for recording paper with low ink fixability, the black component value is limited, and various inconveniences due to low ink fixability are suppressed.

  If the type of the recording sheet is not input by the user, the adjustment parameter a associated with “Other” is used.

  The adjustment parameter table 144 is created in the HDD 144 when the printer driver 351 is installed. When the adjustment parameter table 144 is created, three or more types of recording sheets assumed by the printer vendor and the adjustment parameter a corresponding thereto are stored in the adjustment parameter table 144. The recording paper type and the adjustment parameter a corresponding thereto can be added.

  Further, the PC 10 according to the present embodiment does not perform the above-described weighting calculation for all the recording sheets. For a specific type of recording sheet (for example, glossy sheet) that can be used in the image forming apparatus 40, A lookup table dedicated to the recording paper is stored in advance, and color conversion processing is performed using the lookup table, so weighting processing according to the type of recording paper is not performed. However, the above-described weighting calculation may be executed for all types of recording paper.

  Returning to FIG. The input device 17 is for inputting a user instruction, and includes, for example, a keyboard and a mouse. The display device 18 is composed of, for example, a CRT display or a liquid crystal display, and visually displays various processing contents and input data.

  The image forming apparatus 40 includes a CPU 51 that is an arithmetic device, a ROM 52 that stores various control programs and data executed by the CPU 51, and print data and control signals input from the PC 10 connected to the image forming apparatus 40. And a RAM 53 which is a memory for storing. The CPU 51, ROM 52, and RAM 53 are connected to each other via a bus line 58, and the bus line 58 is connected to an input / output interface 59.

  The input / output port 59 is also connected to a drive unit 57 including a recording head 54, a CR motor 55, and an LF motor 56. As a result, the CPU 51 drives the drive unit 57 to output the recording sheet. Printing can be performed.

  The recording head 54 is formed with nozzles for ejecting ink onto the recording paper. Then, CMYK ink supplied from an ink cartridge (not shown) to the recording head 54 is ejected from the nozzles, and an image is formed on the recording paper.

  The CR motor 55 supplies a driving force for reciprocating a carriage (not shown) on which the recording head 54 is mounted. The LF motor 56 is a motor that rotates a transport roller and a paper discharge roller that transport the recording paper.

  The CPU 51 expands the print data input from the PC 10 into print data that can be printed by the recording head 54, and outputs the data to the recording head 54 as an ejection signal for each nozzle. By driving the recording head 54 in accordance with this ejection signal, ink is ejected from each nozzle, printing is performed on the recording paper, and the CR motor 55 and the LF motor 56 are ejected to the recording head 54. It is driven in synchronization with the signal.

  The input / output port 59 is connected to the operation key 45, the LCD 46, the memory card slot 47, and the USB interface 48. As a result, the CPU 51 can control each unit.

  FIG. 5 is a functional block diagram for explaining the main part of the color conversion process (S6) executed by the PC 10 in units of functions. Note that the names and symbols of the blocks shown in FIG. 5 correspond to the names and symbols assigned to the processes included in the color conversion process (S6) shown in the flowcharts of FIGS.

  First, in the color conversion process (S62) using the LUT, the input color data RGB is converted into primary conversion data C1M1Y1 according to the relationship stored in the lookup table 142 (see FIG. 2) and output.

  In the first CMYK conversion process (S64), the black component value K1 is added to the primary conversion data C1M1Y1 output from the color conversion process (S62) using the LUT to generate and output the first color data C1M1Y1K1. The black component value K1 added here is “0”.

  The gray component determination process (S65) is a process for determining and outputting the gray component minK to the primary conversion data C1M1Y1 based on the input color data RGB.

  The correction value acquisition process (S66) is a process for acquiring and outputting correction values (ΔC, ΔM, ΔY, ΔK) corresponding to the gray component minK using the GCR table 143 (see FIG. 2).

  The second CMYK conversion process (S67) uses the gray component minK determined by the gray component determination process (S65) and the correction values (ΔC, ΔM, ΔY, ΔK) acquired by the correction value acquisition process (S66). Thus, the input color data RGB is converted to the second color conversion data C2M2Y2K2 by correcting the primary conversion data C1M1Y1. In the second CMYK conversion processing (S67), the arithmetic processing shown in the above equations (2) to (5) is performed.

  The adjustment parameter determination process (S68) is a process for acquiring and outputting the adjustment parameter a corresponding to the type of recording paper to be image formed from the adjustment parameter table 144. Note that the type of recording paper to be image-formed is determined based on input from the user.

  The output value acquisition process (S70) uses the first color data C1M1Y1K1 converted by the first CMYK conversion process (S64) and the second color data C2M2Y2K2 converted by the second CMYK conversion process (S67) as the adjustment parameter a. In this process, the output color data CMYK is obtained by weighting accordingly. The calculation process in the output value acquisition process (S70) is expressed as the above equation (6).

  As described above, according to the PC 10 of the first embodiment, by executing the color conversion process (S6), the adjustment parameter a corresponding to the type of recording paper to be image formed is determined, and the determined adjustment parameter is determined. According to a, the first color data C1M1Y1K1 and the second color data C2M2Y2K2 in which the black component value K2 for the same input color data RGB is equal to or greater than the black component value K1 included in the first color data C1M1Y1K1 are weighted. Thus, the output color data CMYK is acquired, so that the black component value K included in the output color data CMYK can be set to an appropriate value according to the type of recording paper. Further, since the weighting is performed using the adjustment parameter a stored in accordance with the type of storage paper, the memory usage is suppressed as compared with the case where the optimum black component value K is stored for each type of storage paper. can do.

  FIG. 6 is a flowchart showing the page printing process (S1) executed by the PC 10 described above. This page printing process (S1) is a process that is executed when data to be printed (hereinafter referred to as printing target data) is designated and a printing instruction is issued by the user in the PC 10, referring to FIG. This process includes the color conversion process (S6) described. In order to facilitate understanding of the flowchart, it is assumed that the data to be printed is composed of data for one page.

  In the page printing process (S1), first, information on the print size and the paper type is acquired (S2). The print size information is information indicating the size of the print target file. The paper type information is input by the user.

  Next, pixel data for one pixel is acquired as input color data RGB from the print target data (S4), and color conversion processing (S6) for converting the input color data RGB into output color data CMYK is executed.

  Then, halftone processing is executed for the output color data CMYK obtained by the color conversion processing (S6) (S8), and it is determined whether all pixels have been processed (S10). If the determination in S10 is negative (S10: No), the process returns to S4, the next pixel data is acquired, and the process is repeated.

  When the processing for all the pixels is completed while the processing is repeated in this way (S10: Yes), the data for all the obtained pixels is converted into print data (S12) and transferred to the image forming apparatus 40. (S14), and the process ends. The image forming apparatus 40 that has received the print data ejects CMYK ink onto a recording sheet based on the print data to form an image.

  FIG. 7 is a flowchart showing the color conversion process (S6). The contents of each process (S62 to S70) included in the color conversion process (S6) have been described in detail with the same reference numerals in the functional block diagram shown in FIG. Will be explained.

  First, in the color conversion process (S62) using the LUT, the input color data RGB is converted into the primary conversion data C1M1Y1 according to the relationship stored in the lookup table 142 (see FIG. 2).

  Next, in the first CMYK conversion process (S64), the first color data C1M1Y1K1 is generated by adding the black component value K1 having a value of “0” to the primary conversion data C1M1Y1 and output.

  Next, in the gray component determination process (S65), the gray component minK is determined, and correction values (ΔC, ΔM, ΔY, ΔK) corresponding to the gray component minK are acquired by the correction value acquisition process (S66). In the second CMYK conversion process (S67), the input color data RGB is converted to the second color by correcting the primary conversion data C1M1Y1 using the gray component minK and the correction values (ΔC, ΔM, ΔY, ΔK). Conversion data C2M2Y2K2 is converted.

  In the adjustment parameter determination process (S68), an adjustment parameter a corresponding to the type of recording paper to be image-formed is acquired from the adjustment parameter table 144. In the output value acquisition process (S70), the first color data C1M1Y1K1 and The output color data CMYK is obtained by weighting the second color data C2M2Y2K2 according to the adjustment parameter a.

  According to the color conversion process (S6) of the first embodiment, the black component value K included in the output color data CMYK can be set to an appropriate value according to the type of recording paper.

  Also, the second color data C2M2Y2K2 corrected in accordance with the gray component minK is weighted by the adjustment parameter a corresponding to the type of recording paper and reflected in the output color data CMYK, so that the memory is used according to the gray component. A decrease in image quality (color shade) can be suppressed while suppressing the amount.

  Further, since the primary conversion data C1M1Y1 converted by the color conversion process using the LUT (S62) is reflected in both the first color data C1M1Y1K1 and the second color data C2M2Y2K2, the processing efficiency is high.

  Further, an appropriate achromatic color component corresponding to the type of recording paper is determined from the two relationships of the relationship stored in the lookup table 142 (see FIG. 2) and the relationship stored in the GCR table 143 (see FIG. 2). Since the value is obtained, the memory usage can be suppressed as compared with the case where the optimum black component value is stored for each type of recording paper.

  Next, a second embodiment will be described. FIG. 8 is a connection diagram showing a connection relationship between the PC 100, which is the second embodiment of the color conversion apparatus of the present invention, and the image forming apparatus 40, and corresponds to FIG. In the second embodiment, the same parts as those in the first embodiment described above are denoted by the same reference numerals and description thereof is omitted.

  As shown in FIG. 8, the HDD 14 of the PC 100 according to the second embodiment executes the color conversion process (S610) shown in FIG. 10 instead of the printer driver 141 stored in the PC 10 according to the first embodiment. A printer driver 145 is stored (installed). In addition, a third lookup table 146 and a fourth lookup table 147 are stored.

  The third lookup table 146 is a table that stores the relationship between the black component value K1 and the chromatic color component values C1, M1, and Y1 for the input color data RGB. In the second embodiment, data obtained by converting the input color data RGB in accordance with the relationship stored in the third lookup table 146 is referred to as first color data C1M1Y1K1.

  The fourth lookup table 147 is a table that stores the relationship between the black component value K2 and the chromatic color component values C2, M2, and Y2 with respect to the input color data RGB. In the second embodiment, data obtained by converting the input color data RGB in accordance with the relationship stored in the fourth lookup table 147 is referred to as second color data C2M2Y2K2.

  The third look-up table 146 and the fourth look-up table 147 are both black components for the input color data RGB in order to match the display color on the display device 18 of the PC 10 with the color formed in the image forming device 40. This is common in that the relationship between the value and the chromatic color component value is stored, but when the black component value K1 and the black component value K2 for the same input color data RGB are compared, the relationship of K2 ≧ K1 always holds. As described above, the third lookup table 146 and the fourth lookup table 147 are created in advance. As a result, the black component value of the second color data C2M2Y2K2 corresponding to the same input color data RGB is greater than or equal to the black component value of the first color data C1M1Y1K1.

  FIG. 9 is a functional block diagram for explaining the main part of the color conversion processing (S610) executed by the PC 100 of the second embodiment in units of functions, and is a diagram corresponding to FIG.

  First, in the CMYK conversion process (S612) using the third LUT, the input color data RGB is converted into the first color data C1M1Y1K1 according to the relationship stored in the third lookup table 146, and output.

  In the CMYK conversion process (S614) using the fourth LUT, the input color data RGB is converted into the second color data C2M2Y2K2 according to the relationship stored in the fourth lookup table 147, and is output.

  As described in the first embodiment, the adjustment parameter determination process (S68) is a process for obtaining and outputting the adjustment parameter a corresponding to the type of recording paper to be image formed from the adjustment parameter table 144.

  The output value acquisition process (S616) includes the first color data C1M1Y1K1 converted by the CMYK conversion process (S612) using the third LUT and the second color data converted by the CMYK conversion process (S614) using the fourth LUT. In this process, the output color data CMYK is obtained by weighting C2M2Y2K2 according to the adjustment parameter a. When the calculation process in the output value acquisition process (S616) is expressed by a mathematical formula, it is the same as the formula (6) described above in the first embodiment.

  FIG. 10 is a flowchart illustrating the color conversion process (S610) of the second embodiment. The color conversion process (S610) of the second embodiment is a process that can be executed instead of the color conversion process (S6) of the first embodiment.

  The contents of the processes (S612, S614, S68, S616) included in the color conversion process (S610) shown in FIG. 10 are described in detail with the same reference numerals in the functional block diagram shown in FIG. Therefore, each process will be briefly described in this flowchart.

  First, in the color conversion process (S612) using the third LUT, the input color data RGB is converted into the first color data C1M1Y1K1 according to the relationship stored in the third lookup table 146 (see FIG. 8).

  Next, in the color conversion process (S614) using the fourth LUT, the input color data RGB is converted into the second color data C2M2Y2K2 in accordance with the relationship stored in the fourth lookup table 147.

  Then, in the adjustment parameter determination process (S68), the adjustment parameter a corresponding to the type of recording paper to be image formed is acquired from the adjustment parameter table 144, and in the output value acquisition process (S616), the first color data C1M1Y1K1 and The output color data CMYK is obtained by weighting the second color data C2M2Y2K2 according to the adjustment parameter a.

  According to the PC 100, an appropriate black component value corresponding to the type of recording paper is obtained from the two look-up tables 146 and 147 and the adjustment parameter table 144, so that the optimum black component value for each type of recording paper is obtained. The amount of memory used can be suppressed as compared with the case of storing.

  The first color data C1M1Y1K1 and the second color data C2M2Y2K2 are both third lookup tables 146 that are predetermined for color matching between the display color on the PC 100 and the color formed on the image forming apparatus 40. Since the output color data CMYK obtained by using these values is obtained using the fourth look-up table 147, an image having a color that does not feel uncomfortable with the display color of the PC 100 is displayed in the image forming apparatus 40. Can be formed. That is, an appropriate black component value corresponding to the type of recording paper and an appropriate chromatic color component value corresponding to the black component value are obtained.

  Next, a third embodiment will be described. FIG. 11 is a connection diagram showing a connection relationship between the PC 200 that is the third embodiment of the color conversion apparatus of the present invention and the image forming apparatus 40, and corresponds to FIG. In the third embodiment, the same portions as those in the first embodiment described above are denoted by the same reference numerals and description thereof is omitted.

  As shown in FIG. 11, the page printing process (S71) shown in FIG. 13 is executed on the HDD 14 of the PC 200 of the third embodiment in place of the printer driver 141 stored in the PC 10 of the first embodiment. A printer driver 148 is stored (installed).

  The RAM 13 is provided with a synthesis table storage area 131. In the synthesis table storage area 131, a synthesis table is stored.

  FIG. 12 is a diagram schematically showing the relationship between the third lookup table 146, the fourth lookup table 147, and the synthesis table 150 created based on them. As shown in FIG. 12, the synthesis table 150 includes color component values C1, M1, Y1, and K1 stored in the third lookup table 146 and color component values C2 and M2 stored in the fourth lookup table 147. , Y2, and K2, a table that stores the relationship between the input color data RGB and the output color data CMYK.

As shown in FIG. 12, in the third lookup table 146 and the fourth lookup table 147, the same management number is assigned to the same input color data RGB. For each management number, the component values C1, M1, Y1, K1 and C2, M2, Y2, K2 are read out and weighted according to the adjustment parameter a to be stored in the synthesis table 150. The relationship between the input color data RGB and the output color data CMYK is determined. The output color data CMYK corresponding to the input color data RiGiBi with the management number i is calculated by the arithmetic expression shown in the following (7).
(C, M, Y, K) = a * (C3i, M3i, Y3i, K3i) + (1-a) * (C4i, M4i, Y4i, K4i) (7)
By determining the relationship between such input color data and CMYK color component values for all management numbers, the synthesis table 150 is created.

  As described above, when the third look-up table 146 and the fourth look-up table 147 are compared, the relationship of K2 ≧ K1 is always established. Therefore, a relationship in which the output color data CMYK including an appropriate black component value K corresponding to the type of recording paper and the input color data RGB are associated can be stored in the synthesis table 150.

  The third look-up table 146 and the fourth look-up table 147 are tables determined in advance for color matching between the display color in the PC 200 and the color formed in the image forming apparatus 40. By using the synthesis table 150 obtained by using the image, the relationship between the output color data CMYK and the input color data RGB for forming an image having a color that does not feel uncomfortable with the display color on the PC 100 is synthesized. It can be stored in the table 150.

  FIG. 13A is a flowchart showing the page printing process (S71) executed in the PC 200 of the third embodiment, and corresponds to FIG. In the page printing process (S71) shown in FIG. 13A, the same parts as those in the page printing process (S1) described with reference to FIG. 6 are denoted by the same reference numerals, and description thereof is omitted or simplified.

  In the page printing process (S7), first, a synthesis table creation process (S71) for creating a synthesis table 150 (see FIG. 12) is executed (S72). Details of the synthesis table creation process (S71) will be described later with reference to FIG.

  Next, print size information is acquired (S74). The print size information is information indicating the size of the print target file. Then, pixel data for one pixel is acquired as input color data RGB from the print target data (S4), and color conversion processing (S76) for converting the input color data RGB into output color data CMYK is executed. This color conversion process (S76) is a process for converting the input color data RGB into the output color data CMYK in accordance with the relationship stored in the synthesis table 150 (see FIG. 12).

  In the processing from S8 to S14, the same processing as S8 to S14 in the page printing processing (S1: see FIG. 6) of the first embodiment described above is executed.

  According to the page printing process (S71) of the third embodiment, the type of recording paper is determined based on the two relationships of the relationship stored in the third lookup table 146 and the relationship stored in the fourth lookup table 147. An appropriate black component value corresponding to is obtained. Further, as in the first and second embodiments, the memory usage can be suppressed as compared with the case where the optimum achromatic color component value is stored for each type of recording paper.

  Further, the calculation of the color data using the adjustment parameter corresponding to the type of the recording paper is performed only when printing of the recording paper is started, and it is not necessary to perform it for each pixel of the print image. Therefore, there is an effect that when the image size to be printed on the recording paper is increased, the speed can be further increased as compared with the first and second embodiments.

  FIG. 13B is a flowchart showing the synthesis table creation process (S72). In this synthesis table creation process (S72), first, an adjustment parameter a corresponding to the recording paper type is determined (S721). Since the process of S721 is the same process as the adjustment parameter determination process (S68) described in the first and second embodiments, detailed description thereof is omitted.

  Next, the sizes of the third lookup table 146 and the fourth lookup table 147 are acquired (S722). That is, the maximum value of the management number i (see FIG. 12) is acquired.

  Next, the values (C3i, M3i, Y3i, K3i) of the third lookup table 146 and the values (C4i, M4i, Y4i, K4i) of the fourth lookup table 147 are weighted according to the adjustment parameters. (S723). In S723, the arithmetic processing shown in the above equation (7) is performed.

  Next, it is determined whether or not all the management numbers i have been processed (S724). If the determination in S724 is negative (S724: No), the process returns to S723, and the process is repeated for the next management number i.

  If the determination in S724 is affirmed while the processing is repeated in this way (S724: Yes), the created composite table 150 is saved in the composite table storage area 131 (see FIG. 11) (S726), and the process is performed. Exit.

  Although the present invention has been described based on the embodiments, the present invention is not limited to the above-described embodiments, and various improvements and modifications can be easily made without departing from the spirit of the present invention. Can be inferred.

  For example, the color conversion processing (S6, S610) of the first embodiment and the second embodiment and the page printing processing (S71) of the third embodiment are executed by the PCs 10, 100, 200. It is good also as being executed in. That is, in the first to third embodiments, the PC 10, 100, and 200 execute processing for converting input color data expressed in RGB into output color data expressed in CMYK. The image forming apparatus 40 is configured to execute the above-described color conversion processing (S6, S610) or page printing processing (S71) in accordance with input color data RGB input from the PC 10, 100, 200 or another external device. May be.

  In addition, the image forming apparatus 40 connected to the PCs 10, 100, and 200 of the first to third embodiments uses four colors of inks of C ink, Y ink, M ink, and K ink. The input color data RGB is converted to output color data CMYK including four colors of CMYK. However, when an image forming apparatus that forms an image using five or more colors such as light cyan, light magenta, and light black is used. The input color data may be converted into output color data including five or more colors used in the image forming apparatus.

  In the adjustment parameter determination process (S68) of the first to third embodiments, it has been described that the adjustment parameter a corresponding to the type of the recording paper input by the user is determined. Even if the adjustment parameter a is determined based on the type of the recording paper specified by reading the RFID (Radio Frequency IDentification) or the barcode added to the good.

  Further, instead of the user inputting the type of recording paper, the user may be allowed to input a sensory degree of ink fixing property. For example, the user is prompted to input “good”, “medium”, or “bad” as the fixing property of the ink to the recording paper. In this way, even if the type of recording paper is unknown, an appropriate adjustment parameter a that suits the user's feeling is determined, and the same effects as in the first to third embodiments described above can be obtained.

  In the first embodiment and the second embodiment, each color component value C1, M1, Y1, K1 included in the first color data C1M1Y1K1 is multiplied by a common weight “a” and included in the second color data C2M2Y2K2. Each color component value C2, M2, Y2, K2 has been multiplied by a common weight “(1-a)”. In this way, the color component values in the first color data C1M1Y1K1 and the color component values in the second color data C2M2Y2K2 are added while maintaining the balance, and output color data CMYK is obtained. However, it may be configured to multiply a different weight for each color. In this way, it is possible to output a color that makes the best use of the characteristics of the recording paper.

  Further, after the color conversion process (S6, S610, S71) described above, other processes such as an ink amount adjustment process for correcting the dot gain may be further added.

  In the first CMYK conversion process (S64) of the first embodiment, the black component value K1 having a value of 0 is added to the primary conversion data C1M1Y1 obtained by the color conversion process (S62) using the LUT. First color data C1M1Y1K1 was generated. Instead of this, the primary conversion data C1M1Y1 converted by the color conversion process (S62) using the LUT may be used as the first color data C1M1Y1 without providing the first CMYK conversion process (S64). In this case, the color conversion process (S62) using the LUT corresponds to the seventh color conversion means described in the claims, and the gray component determination process (S65), the correction value acquisition process (S66), and the second CMYK conversion process. (S67) corresponds to the eighth color conversion means described in the claims.

In the correction value acquisition process (S66) of the first embodiment, the correction value corresponding to the gray component minK is acquired according to the relationship stored in the GCR table 143 (see FIG. 3). However, the correction value corresponding to the gray component minK may be acquired according to the relationship stored in the UCR (Under Color Removal) table. In this case, the second color data C2M2Y2K2 can be obtained by calculations shown in the following equations (8) to (11).
C2 = C1-UCR (minK) c (8)
M2 = M1-UCR (minK) m (9)
Y2 = Y1-UCR (minK) y (10)
K2 = minK−UCR (minK) k (11)
Where UCR (minK) c is a C correction value for the gray component minK, UCR (minK) m is an M correction value for the gray component minK, and UCR (minK) y is a Y correction for the gray component minK. UCR (minK) k is a correction value of K for the gray component minK, and is a value acquired according to a UCR table stored in advance.

1 is a connection diagram illustrating a connection relationship between a PC, which is a first embodiment of a color conversion apparatus of the present invention, and an image forming apparatus. 2 is a block diagram illustrating an electrical configuration of a PC and an image forming apparatus. FIG. It is a figure which shows an example of a GCR table. It is a figure which shows an example of an adjustment parameter table typically. It is a functional block diagram for demonstrating the principal part of the color conversion process performed with PC in a functional unit. It is a flowchart which shows the page printing process performed with PC. It is a flowchart which shows a color conversion process. FIG. 4 is a connection diagram illustrating a connection relationship between a PC according to a second embodiment and an image forming apparatus, and corresponds to FIG. 2. It is a functional block diagram for demonstrating the principal part of the color conversion process performed with PC of 2nd Embodiment in a functional unit, and is a figure equivalent to FIG. It is a flowchart which shows the color conversion process of 2nd Embodiment. FIG. 4 is a connection diagram illustrating a connection relationship between a PC according to a third embodiment and an image forming apparatus, and corresponds to FIG. 2. It is a figure which shows typically the relationship between a 3rd lookup table, a 4th lookup table, and the synthetic | combination table created based on them. (A) is a flowchart which shows the page printing process performed with PC of 3rd Embodiment, (b) is a flowchart which shows the synthetic | combination table creation process performed with PC of 3rd Embodiment.

10, 100, 200 PC (an example of a color conversion device)
141, 145, 148 Printer driver (example of color conversion program)
142 Look-up table (an example of first relationship storage means)
143 GCR table (an example of second relation storage means)
146 Third lookup table (an example of third relation storage means and fifth relation storage means)
147 Fourth lookup table (an example of fourth relation storage means and sixth relation storage means)
S62 Example of chromatic color component conversion means, first color conversion means, and first color conversion process S64 Example of first color conversion means and first color conversion process S65 Example of gray component determination means S66, S67 Second color conversion means Example of second color conversion process S68, S721 Example of adjustment value determining means and adjustment value determining process S70, S616 Example of output value acquiring means and output value acquiring process S72 Example of relationship creating means and relationship creating process S78 Obtaining output value Example of Means and Output Value Acquisition Step S612 Example of First Color Conversion Unit S614 Example of Second Color Conversion Unit

Claims (12)

In order to form an image on a recording medium using a color material composed of achromatic pigment ink and a color material composed of chromatic dye ink , the input value is an output value including an achromatic color component value and a chromatic color component value. A color conversion device for converting to
The input value, a first color conversion means for converting the first color data comprising a first chromatic component value and a first achromatic component values,
The entering-force value, a second color conversion means for converting the second color data including a second chromatic component value and a second achromatic component values, said second achromatic component values, The second color conversion means for converting so as to be equal to or greater than the first achromatic color component value included in the first color data ;
An adjustment value determining means for determining an adjustment value according to the fixing property of the achromatic pigment ink to the recording medium to be image-formed;
An output value acquiring means for acquiring the output value using the adjustment value and said first color data and said second color data, according to the adjustment values, converted by the first color conversion means A color conversion apparatus comprising: output value acquisition means for acquiring the output value by weighting the first color data and the second color data converted by the second color conversion means. The output value acquisition unit relates to a recording medium for recording the image, and the higher the fixing property of the achromatic pigment ink, the smaller the weight for the first color data than the weight for the second color data. The color conversion apparatus according to claim 1, wherein the output value is acquired by: Gray component determining means for determining a gray component based on the input value;
The achromatic component values for the input value is predetermined such that the first achromatic component value or more contained in the first color data, the correction value of the chromatic component value corresponding to the gray component and no Second relationship storage means for storing the relationship between the color component value and the correction value;
The second color conversion means includes
A correction value for the chromatic color component value determined in accordance with the relationship stored in the second relationship storage means and a correction value for the achromatic color component value obtained by converting the second chromatic color component value obtained by converting the input value. corrected by the color conversion apparatus according to claim 1, wherein the converting the input value to the second color data using. First relation storage means for storing a relationship between the input value and a chromatic color component value for the input value ;
The first color conversion means according to the relationship stored in the first relationship storing means, provided with a chromatic color component conversion means for converting the input value to said first chromatic component value of the first color data,
The second color conversion means is a correction value for the chromatic color component value determined in accordance with the relationship stored in the second relationship storage means for the first chromatic color component value converted by the chromatic color component conversion means. 4. The color conversion apparatus according to claim 3 , wherein a value obtained by correcting the second color data is the second chromatic color component value of the second color data. The first color conversion unit generates first color data for generating first color data by adding a predetermined achromatic color component value to the first chromatic color component value acquired by the chromatic color component value acquisition unit. 5. The color conversion apparatus according to claim 4, further comprising: means. Third relationship storage means for storing a relationship between the achromatic color component value and the chromatic color component value with respect to the input value;
Wherein is intended to store the relationship between the achromatic component value and the chromatic component value to the input value, the achromatic component values for the input values, the third relationship achromatic component values obtained from the relationship stored in the storage means A fourth relation storage means as described above,
The first color conversion means converts the input value into the first color data according to the relation stored in the third relation storage means.
The second color converting means, wherein in accordance with the stored relationship in the fourth relationship storing means, the color according to claim 1 or 2, characterized in that for converting the input value to the second color data Conversion device. In order to form an image on a recording medium using a color material composed of achromatic pigment ink and a color material composed of chromatic dye ink , the input value is an output value including an achromatic color component value and a chromatic color component value. A color conversion device for converting to
Fifth relationship storage means for storing a relationship between the achromatic color component value and the chromatic color component value with respect to the input value;
Is intended to store the relationship between the achromatic component value and the chromatic component value for the input value, the achromatic component values for the input values, the fifth relationship achromatic component values obtained from the relationship stored in the storage means The sixth relation storage means as described above;
An adjustment value determining means for determining an adjustment value according to the fixing property of the achromatic pigment ink to the recording medium to be image-formed;
According to the adjustment value determined by the adjustment value determining means, the achromatic color component value and the chromatic color component value stored in the fifth relation storage means and the achromatic color component value stored in the sixth relation storage means A relationship creating means for creating a relationship between the input value, the achromatic color component value, and the chromatic color component value by weighting the chromatic color component value;
A color conversion apparatus comprising: an output value acquisition unit configured to convert the input value and acquire the output value according to the relationship created by the relationship creation unit. In order to form an image on a recording medium using a color material composed of achromatic pigment ink and a color material composed of chromatic dye ink , the input value is an output value including an achromatic color component value and a chromatic color component value. A color conversion device for converting to
The input value, a seventh color conversion means for converting the first color data which does not include the achromatic component values comprises a first chromatic component values,
The input value, and the eighth color converting means for converting the second color data including a second chromatic component value and a second achromatic component values,
An adjustment value determining means for determining an adjustment value according to the fixing property of the achromatic pigment ink to the recording medium to be image-formed;
An output value acquiring means for acquiring the output value using the adjustment value and said first color data and said second color data, according to the adjustment values, converted by the seventh color conversion means A color conversion apparatus comprising: output value acquisition means for acquiring the output value by weighting the first color data and the second color data converted by the eighth color conversion means. In order to form an image on a recording medium using a color material composed of achromatic pigment ink and a color material composed of chromatic dye ink , the input value is an output value including an achromatic color component value and a chromatic color component value. A color conversion program for causing a computer to execute a process of converting to
The computer,
The input value, a first color conversion means for converting the first color data comprising a first chromatic component value and a first achromatic component values,
The entering-force value, a second color conversion means for converting the second color data including a second chromatic component value and a second achromatic component values, said second achromatic component values, The second color conversion means for converting so as to be equal to or greater than the first achromatic color component value included in the first color data ;
An adjustment value determining means for determining an adjustment value according to the fixing property of the achromatic pigment ink to the recording medium to be image-formed;
An output value acquiring means for acquiring the output value using the adjustment value and said first color data and said second color data, according to the adjustment values, converted by the first color conversion means the color conversion program for causing to function as an output value acquiring means for acquiring the output value by weighting the second color data converted by the first color data second color conversion means. In order to form an image on a recording medium using a color material composed of achromatic pigment ink and a color material composed of chromatic dye ink , the input value is an output value including an achromatic color component value and a chromatic color component value. A color conversion program for causing a computer to execute a process of converting to
The computer
Fifth relationship storage means for storing a relationship between the achromatic color component value and the chromatic color component value with respect to the input value;
Is intended to store the relationship between the achromatic component value and the chromatic component value for the input value, the achromatic component values for the input values, the fifth relationship achromatic component values obtained from the relationship stored in the storage means The sixth relation storage means as described above,
The computer,
An adjustment value determining means for determining an adjustment value according to the fixing property of the achromatic pigment ink to the recording medium to be image-formed;
According to the adjustment value determined by the adjustment value determining means, the achromatic color component value and the chromatic color component value stored in the fifth relation storage means and the achromatic color component value stored in the sixth relation storage means A relationship creating means for creating a relationship between the input value, the achromatic color component value, and the chromatic color component value by weighting the chromatic color component value;
Wherein in response to the created relationship by relationship creation unit, a color conversion program for causing to function as an output value acquiring means for acquiring the output value to convert the input value. In order to form an image on a recording medium using a color material composed of achromatic pigment ink and a color material composed of chromatic dye ink , the input value is an output value including an achromatic color component value and a chromatic color component value. A color conversion method for converting to
The input value, a first color conversion step of converting the first color data comprising a first chromatic component value and a first achromatic component values,
The entering-force value, a second color conversion step of converting the second color data including a second chromatic component value and a second achromatic component values, said second achromatic component values, The second color conversion step of converting the first achromatic color component value included in the first color data to be equal to or higher than the first achromatic color component value ;
An adjustment value determining step for determining an adjustment value according to the fixing property of the achromatic pigment ink to the recording medium to be imaged;
An output value obtaining step of obtaining the output value using the adjustment value and said first color data and said second color data, according to the adjustment values, converted by the first color conversion step A color conversion method comprising: an output value acquisition step of acquiring the output value by weighting the first color data and the second color data converted by the second color conversion step. In order to form an image on a recording medium using a color material composed of achromatic pigment ink and a color material composed of chromatic dye ink , the input value is an output value including an achromatic color component value and a chromatic color component value. A color conversion method for converting to
An adjustment value determining step for determining an adjustment value according to the fixing property of the achromatic pigment ink to the recording medium to be imaged;
A fifth relationship storing means for storing a relationship between the achromatic component value and the chromatic component value for the input value, which stores the relationship between the achromatic component value and the chromatic component value for the input value, the The adjustment value determined by the adjustment value determination step is set using the sixth relationship storage means in which the achromatic color component value for the input value is equal to or greater than the achromatic color component value obtained from the relationship stored in the fifth relationship storage means. In response, the achromatic color component value and the chromatic color component value stored in the fifth relation storage means and the achromatic color component value and the chromatic color component value stored in the sixth relation storage means are weighted. A relationship creating step of creating a relationship between the value, the achromatic color component value, and the chromatic color component value;
Wherein in response to the created relationship by relationship creation process, a color conversion method, which comprises an output value acquisition step of converting the input values to obtain the output value.

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