JP2014195171A - System and method for generating gamut database - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gamut database generating system which easily generates a gamut database for acquiring types of base inks which reproduce colors of compound inks to be compounded in accordance with a material of a base to be colored and a compound ratio of respective inks when a designer selects colors.SOLUTION: A gamut database generating system includes: a base ink selecting section for selecting base inks used for generating a compound ink with attribute data which are previously set; a combination design section for setting a compound group of the plurality of base inks which adjust the color of the compound ink; an initial compound setting section for setting a compound ratio of the respective base inks of the compound group; a spectral reflection factor calculating section for acquiring a spectral reflection factor of the compound ink by the compound group for each compound ratio; and a coordinate value calculating section for acquiring the color of the compound ink in a color space from the spectral reflection factor. A coordinate value, the compound group, the compound ratio, the spectral reflection factor and the attribute data are made to correspond to each other to be written into an external database.

Description

  The present invention relates to a color gamut database creation system and method used for color matching of chromatic products.

Conventionally, in color products such as packaging and clothes, the color determinant (for example, product designer) specifies the color to be colored, and the color product manufacturer performs the work of reproducing this specified color. The product is colored.
Here, a color sample book is generally used for designating a color to be colored. For example, several thousand colors are prepared for the color sample book. Further, in the color sample book, a general printable paper such as art paper is used as a background material to be colored, and offset printing is mainly used as a printing method on these papers.

When the color decider uses the color sample book, it is necessary to pass the color chip of the same color sample separated from the color sample book when specifying the color to convey the specified color to the concerned parties. When the decision maker decides the color, the stakeholder always needs to prepare a color sample book in which all colors are completely present.
In addition, the color of the color sample book is limited, and the color decider cannot select the color that the user really wants. In addition, because the composition information of the ink necessary for coloring the color of the color sample book and the number of types of base material to be colored are limited, the color determined by the color product manufacturer using different materials The work to reproduce must be done. That is, a coloring product manufacturer uses, for example, a color matching system, and reproduces a color designed by a color determiner based on the color chip color as a color sample, in accordance with the underlying material to be colored. There is a need (see, for example, Patent Document 1). For this reason, in the color matching operation, trial and error such as selection of the ink type according to the printing method, mixing ratio, and the like are required, which requires equipment investment, manpower and time.

  In recent years, designers of color products have designed products and colors using applications on personal computers (hereinafter referred to as PCs) (for example, Adobe Illustrator (registered trademark)). At this time, the designer conducts color confirmation using a color sample displayed on the screen of the PC, creates a mockup by ink jet printing, etc., and examines a design plan for the colored product. Thereby, as compared with the color sample book, the continuity of colors that can be selected by the color determiner can be obtained, and the range for selecting a desired color is widened.

However, the color displayed on the screen of the PC cannot be confirmed in a state of coloring the material of the product to be designed. In addition, it is desirable that mock-up by inkjet printing or the like can be confirmed in a colored state on the product material to be designed in the same manner as the color sample book, but in general, it is confirmed with a material different from the product.
Therefore, in order to reproduce the color designed by the color decider, the coloring product manufacturer, like the color swatch book, information on the ink composition necessary for coloring and the type of material (material) for coloring However, since it is different from the actual coloring product, complicated color matching work is performed. In addition, the color of the color swatch book specified by the color determiner may not be reproduced with the materials used in coloring products, so it takes a lot of time to finalize the color, or the process of redesigning the color A reversal has occurred.

JP 2009-163759 A

  The present invention has been made in view of the above points, and at the time of color selection by the designer, the type of base ink for reproducing the color of the compounded ink to be blended, corresponding to the background material colored by the designer, It is an object of the present invention to provide a color gamut database creation system and method for easily creating a color gamut database for obtaining the blending ratio and spectral reflectance of these inks.

  The present invention has been made to solve the above-described problems, and the color gamut database creation system of the present invention includes a base ink selection unit that selects a base ink to be used for creating a blended ink in accordance with preset selection conditions; A combination design unit that sets a blending group of the base inks of a plurality of different colors that adjust the color of the blending ink, an initial blending setting unit that sets each blending ratio of the base ink in the blending group, A spectral reflectance calculation unit for obtaining the spectral reflectance of the blended ink by the blending group for each blending ratio, and a coordinate value calculating unit for obtaining the coordinate value of the color of the blended ink in a predetermined color space from the spectral reflectance. , The coordinate value, the blending group, the blending ratio, the spectral reflectance, and the selection condition, And writes to the database.

  The color gamut database creation system of the present invention detects a region where the coordinate values in the color space are sparse, and complements the no-data coordinate position where the coordinate values are not obtained in the region where the coordinate values are sparse, While changing the blending ratio of the coordinate values adjacent to the non-data coordinate position, the spectral reflectance calculation unit calculates the spectral reflectance at the changed blending ratio, and the coordinate value calculation unit causes the spectral reflection to be performed. A spatial data complementing unit that calculates the coordinate value from a rate, obtains the blending ratio of the coordinate value that is the non-data coordinate position, and supplements the coordinate value of a sparse area in the color space. Features.

  The color gamut database creation system of the present invention further includes a material setting unit that selects a background material to be colored with the blended ink, and the coordinate value calculation unit adds the spectral reflectance of the blended ink, The coordinate value is calculated using a spectral reflectance.

  In the color gamut database creation system of the present invention, the coordinate value calculation unit calculates the coordinate value using spectral characteristics of a light source that illuminates a colored product colored with the blended ink in addition to the spectral reflectance of the blended ink. It is characterized by doing.

  The color gamut database creation method of the present invention includes a base ink selection process in which a base ink used to create a blended ink is selected according to preset selection conditions, and the bases of a plurality of different colors that adjust the color of the blended ink. A combination design process for setting an ink blending group, an initial blending process for setting each blending ratio of the base ink in the blending group, and a spectral reflectance of blended ink by the blending group for each blending ratio is obtained. Spectral reflectance calculation process, coordinate value calculation process for determining the coordinate value of the color of the blended ink in a predetermined color space from the spectral reflectance, the coordinate value, the blending group, the blending ratio, the spectral reflectance, A data writing process that associates the selection conditions with each other and writes them to an external color gamut database. The features.

  According to this invention, at the time of color selection by the designer, the type of base ink for reproducing the color of the blended ink corresponding to the base material colored by the designer, the blending ratio and spectral reflectance of these inks Can easily create a color gamut database

1 is a schematic block diagram illustrating a configuration example of a color gamut database creation system 1 according to an embodiment of the present invention. The structure of the base material table previously written and stored in the material database 20 is shown. An example of the configuration of a base ink table that is written and stored in advance in the base ink database 19 is shown. As an example, the types of resistance characteristics in offset ink and gravure ink and explanation of the resistance are shown. It is a figure which shows the structural example of the mixing | blending ink table in which the mixing | blending information of mixing | blending ink is described. It is the figure which plotted the L ^* a ^* b ^* value of each mixing | blending ink mix | blended initially at each coordinate of L ^* a ^* b ^* color space. It is a flowchart which shows the operation | movement in preparation of the mixing | blending ink table of the color gamut database preparation system 1 by this embodiment. It is a figure explaining the discretization of the L ^* a ^* b ^* value which L ^* a ^* b ^* space complementation part 17 performs. It is a figure explaining the setting of the discretization L ^* a ^* b ^* value contained in the compounding calculation object L ^* a ^* b ^* group of calculation object. It is a figure explaining the process which calculates the mixture ratio of the discretization L ^* a ^* b ^* value contained in L ^* a ^* b ^* group which is not a composition calculation object.

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic block diagram showing a configuration example of a color gamut database creation system 1 according to an embodiment of the present invention.
In FIG. 1, the color gamut database creation system 1 includes a material setting unit 11, a base ink selection unit 12, a combination design unit 13, an initial blend setting unit 14, a spectral reflectance calculation unit 15, and an L ^* a ^* b ^* calculation unit 16. L ^* a ^* b ^* spatial data complementing unit 17, display unit 18, base ink database 19 and material database 20. Further, the color gamut database creation system 1 writes the created color gamut data in a blended ink table that is previously written and stored in the external reproducible color gamut database 100.

The material setting unit 11 reads from the base material table in which the type of the base material on which the mixed ink (special color ink) is printed (special color printing) is written in advance in the material database 20 and is the material name A list of names is displayed on the display unit 18 to prompt the operator to select a material from the list.
In addition, when the operator selects a material from the list displayed on the display unit 18, the material setting unit 11 sends the background material identification information of the selected material to the base ink selection unit 12 and the spectral reflectance calculation unit 15. Output.

  In the material database 20, the base material table shown in FIG. 2 is written and stored in advance. FIG. 2 shows the structure of the base material table that is written and stored in advance in the material database 20. In FIG. 2, the base material table is composed of a base material identification information for identifying a base material, a material name that is a name of the material indicated by the base material identification information, and spectral reflectance data of the material. Has been. Spectral reflectance is stored in increments of 10 nm from 380 nm to 780 nm. As the material name, for example, there is a name of a base material to be colored such as coated paper or aluminum (aluminum).

Here, the measurement conditions of the spectral reflectance are, for example, when a spectrophotometer (CM-2600d) manufactured by Minolta is used, D / 8 (specular reflection light capture) or d / 8 (specular reflection light) by an integrating sphere. When the spectrophotometer SpectroEye (registered trademark) manufactured by X-Rite is used, it is 45/0 (including filter conditions). These measurement conditions memorize | store a measuring machine name and measurement conditions with the measured spectral reflectance. The color value L ^* a ^* b ^* value (L ^* a ^* b ^* ) stored in the material database 20 is, for example, a calculated value using a D50 / 2 degree field of view, and the calculation method is in JIS Z8729. Use the method.

The base ink selection unit 12 selects a base ink applicable to the base material selected by the operator from the base inks stored in the base ink database 19.
The base ink selection unit 12 groups the base inks applicable to the coloring of the selected background material based on attribute data such as tolerance data, transparency, and price. For example, grouping (classification) is made into a group of base inks whose light resistance is higher than a predetermined value, a group of base inks whose acid resistance is higher than a predetermined value and whose price is lower than a predetermined price. Conditions for attribute data such as tolerance data, transparency, and price for creating this group are set in advance by the operator.

Here, the base ink selection unit 12 displays the set of attribute data of the set group, and the selection of which attribute data set is set as the group of base inks for generating the blending color, Prompt the operator.
Further, the base ink selection unit 12 outputs a group of base inks corresponding to the combination of attribute data selected by the operator to the combination design unit 13.

  In the base ink database 19, the base ink table shown in FIG. 3 is written and stored in advance. FIG. 3 shows a configuration example of a base ink table that is written and stored in advance in the base ink database 19. In FIG. 3, the base ink table includes, for example, base ink identification information for identifying the base ink, a name of the type of base ink indicated by the base ink identification information, a color name indicating the color of the ink base, Base material color material density, optical density (numerical value calculated by the following equation (1) from spectral reflectance) (for each wavelength λ described later), and background information corresponding to the name of the base material that can be printed And the unit price, the transparency of the base ink, the tolerance data indicating the evaluation value of the resistance characteristic of the base ink, the area where this base ink can be obtained and used, and the response to the chemical regulations in that area Information, etc., measuring device information for measuring the spectral reflectance, and the type of illumination as a measurement condition for measuring the spectral reflectance are configured as a set. The attribute data includes transparency, price, tolerance data, and the like.

  Here, the types of base ink include oil-based offset ink, UV (ultraviolet) curable ink, gravure ink, flexographic ink, silk screen printing ink, and metal ink. Examples of color names include red, yellow, blue, green, and orange. In addition, the background correspondence information indicates the names of printable background materials, and when all the information is all, it indicates that all background materials can be handled. As for the price, a standard selling price for each predetermined unit, for example, 1 kg (kilogram) is described.

  The measurement apparatus information includes measurement conditions such as the presence / absence of a filter and the presence / absence of a specular reflection component in addition to the manufacturer, product name, and model number of the spectral reflectance. For example, when the spectrophotometer CM-2600d manufactured by Minolta is used, the measurement conditions for the spectral reflectance are D / 8 (specular reflection light capture) or d / 8 (specular reflection non-capture) using an integrating sphere, When a spectrophotometer SpectroEye (registered trademark) manufactured by X-Rite is used, it is 45/0 (including filter conditions). These measurement conditions are written and stored in the base ink table of the base ink database 19 together with the spectral reflectance measured to determine the optical density and the name of the measuring instrument that measured the spectral reflectance. The measurement conditions are the same as in the case of the spectral reflectance of the base material. Further, the transparency is obtained by evaluating a color developing material of the base ink (for example, a color developing material which is a medium for uniformly dispersing and adhering the pigment), and is replaced by a numerical value of 0-5, for example.

  In the above equation (1), N is the optical density, R is the spectral reflectance, and x is an arbitrary coefficient.

The resistance data includes the characteristics required to be used for each application, such as the light resistance, alkali resistance, solvent resistance, water resistance, acid resistance, boil resistance, retort resistance, etc. shown in the table of FIG. is there.
FIG. 4 shows, as an example, types of resistance characteristics in offset ink and gravure ink and an explanation of the resistance.
In FIG. 4, the light resistance indicates an evaluation of resistance to the degree of fading due to ultraviolet rays contained in fluorescent lamps and sunlight. Moreover, alkali resistance has shown the evaluation of the tolerance with respect to the fading and discoloration by the environment which has alkalinity. The solvent resistance indicates an evaluation of resistance to fading and discoloration caused by an attached solvent. The water resistance indicates an evaluation of resistance to fading and discoloration caused by attached water. Acid resistance indicates an evaluation of resistance to fading and discoloration caused by a liquid having attached acidity. The boil resistance indicates an evaluation of resistance to fading and discoloration due to temperature when heated. The retort resistance indicates an evaluation of resistance to fading and discoloration due to temperature when the contents are sterilized or heated.

Returning to FIG. 1, when the group of base inks selected by the operator is supplied, the combination design unit 13 selects two or more different base inks in the group and sets the base inks for blending the blended inks. Generate a combination.
As described above, the combination design unit 13 sets a combination of, for example, two to three different types of base inks when mixing different colors of base inks. At this time, when the combination design unit 13 designs a combination of base inks of different colors, combinations of colors that are not generally used are set in advance as exclusion combinations.

And the combination design part 13 confirms the combination of the color produced | generated, and when this exclusion combination is detected, this combination is deleted and it excludes from the color design of mixing | blending ink. For example, the exclusion combination is a combination of base inks that is not common in color matching operations such as orange / purple / grass or yellow / purple / green. Moreover, you may add the combination of base ink which may become a color with low possibility of being used as a color to the exclusion combination mentioned above. Hereinafter, this color combination is referred to as a blended ink set.
Further, the combination design unit 13 writes and stores each of the prepared blended ink sets in the base ink database 19 as a blended ink set table.

The initial blend setting unit 14 sequentially extracts blended ink sets one by one from the blended ink set table of the base ink database 19.
Further, the initial blend setting unit 14 sets the ratio of each combination of base inks constituting the blend ink set.
For example, when the combination ink set is composed of three types of base inks, the combination ratio of these three types of base ink I ₁ , base ink I ₂ and base ink I ₃ , a ₁ : a ₂ : a ₃ is set. To do. At this time, for example, the step size of the blending ratio is 10% for the color excluding the black color, and 2% for the black color.

In addition, for example, when the blending amount is small due to the characteristics of the pigment used in the base ink, discoloration due to external factors becomes prominent, so there is a blending amount restriction that affects the resistance performance of the ink and printed matter Depending on the characteristics, in the type of base ink having an upper limit and a lower limit of the ratio to be blended, either or both of the upper limit and the lower limit of this ratio are set.
As an example, the upper limit of the blending ratio is set to 30% in the case of a black color, and the lower limit is set to 2% in the case of a base ink having a low color resistance compared to other base inks blended.
Then, when the initial blending setting unit 14 has a ratio of 10 steps with one ink base in 10% increments,
[a ₁ , a ₂ , a ₃ ]
= {[0.1,0.1,0.8], ..., [0.1,0.8,0.1], ..., [0.8,0.1,0.1]}
A set of blending ratios (blending ratios) is generated as design data (a ₁ + a ₂ + a ₃ = 1).

The spectral reflectance calculator 15 calculates the spectral reflectance and the L ^* a ^* b ^* value (the coordinate value in the L ^* a ^* b ^* color space, that is, the color value) for the combination of the initial blends. Here, the spectral reflectance calculation unit 15 calculates the spectral reflectance of the blended ink according to the following formula (2) and formula (1) described above, and the blending ratio a _i and optical density N _i ( From (λ), the optical density Nc (λ) when the mixed ink obtained by blending is colored on the base material is calculated. Here, i is the number of base inks to be blended. The optical density is stored in the base ink database 19 in increments of 10 nm, for example, from a wavelength λ of 380 nm to 780 nm. The spectral reflectance calculator 15 calculates the spectral reflectance of the blended ink in increments of 10 nm, for example, from a wavelength λ of 380 nm to 780 nm, similarly to the optical density.

In the formula (2), Nc is the optical density when the blended ink is colored on the base material, Ni is the optical density of the blended base ink, and a _i (for example, the above a ₁ , a ₂ , a ₃ ) is a blending ratio. i is the number of types of base inks to be blended. Further, the spectral reflectance calculator 15 obtains the optical density Nw of the base material by reading the spectral reflectance of the base material from the base material table and substituting it into the equation (1).
For example, when blended ink is blended using three types of base ink (n = 3), the spectral reflectance of each initial blend of the blended ink set is expressed by the following formula (2) in the spectral reflectance calculator 15. Is calculated by For example, each of red (optical density N ₁ (λ)), green (optical density N ₂ (λ)), and blue (optical density N ₃ (λ)) is mixed at a 3: 3: 4 mixing ratio (a ₁ = 0.3, a ₂ = 0.3, a ₃ = 0.4), the spectral reflectance R (λ) _comp when coloring the blended ink on the base material is (3 )

As described above, the optical density for each wavelength is written and stored in advance in the base ink table. For example, when the spectrophotometer CM-2600d manufactured by Minolta is used, the spectral reflectance used when calculating the optical density is D / 8 (specular reflection light capturing) or d / 8 (specular reflection) using an integrating sphere. When a spectrophotometer SpectroEye (registered trademark) manufactured by X-Rite Co., Ltd. or a spectrophotometer manufactured by X-Rite is used, the measurement is performed under measurement conditions of 45/0 (including filter conditions). These measurement conditions memorize | store a measuring machine name and measurement conditions with the measured spectral reflectance. The stored color value L ^* a ^* b ^* value is a calculated value based on, for example, a D50 / 2 degree field of view, and the method of JIS Z8729 is used as the calculation method.

The L ^* a ^* b ^* calculation unit 16 is set in advance from the spectral reflectance R (λ) _{comp of} the blended ink calculated by the spectral reflectance calculation unit 15, the color matching function, and the spectral reflection intensity of illumination. L ^* a ^* b ^* values (color values when colored on the base material) of each of the initial blended inks are calculated using a conversion formula that performs conversion from a general spectral reflectance.

FIG. 5 is a diagram illustrating a configuration example of a blended ink table in which blending information of blended ink is described. The blended ink table in FIG. 5 is written and stored in the reproducible color gamut database 100. In this blended ink table, the spectral reflectance and the L ^* a ^* b ^* color space (color space) when a plurality of different types of base inks such as two or three are blended (mixed at a blending ratio described later) are used. Color value data indicates a coordinate value (L ^* a ^* b ^* value) and indicates a reproducible color gamut.

FIG. 5A also shows, as an example, base material identification information for identifying a base material that is the base of the blended ink, spectral reflectance and color management, together with blended ink identification information for identifying the blended ink. Color number, L ^* a ^* b ^* value, information on the measuring device that measured the spectral reflectance of the base ink, and base ink information (including the blending ratio) used for blending the blended ink, There are columns of attribute data such as the region where the used base ink can be obtained and used, and correspondence information.

Further, the base ink information in FIG. 5A has a configuration shown in FIG.
FIG. 5B shows base ink identification information for identifying the base ink used for blending the blended ink, blending ratio, and the like.

FIG. 6 is a diagram in which the L ^* a ^* b ^* values of the blended inks initially blended are plotted on the coordinates of the L ^* a ^* b ^* color space.
Returning to FIG. 1, when blending the initial blended ink, even if the blend of the base ink is changed at a predetermined rate, for example, by 10%, each blend is performed in the L ^* a ^* b ^* color space of FIG. The coordinates are not determined at predetermined intervals. For this reason, the L ^* a ^* b ^* space data complementing unit 17 described later does not calculate the L ^* a ^* b ^* values corresponding to the coordinate values in the L ^* a ^* b ^* color space of FIG. The L ^* a ^* b ^* value of the region is complemented.

The L ^* a ^* b ^* spatial data complementing unit 17 detects the continuity of the presence / absence of the L ^* a ^* b ^* value in the coordinate values of the L ^* a ^* b ^* space in FIG. 6, and the L ^* a ^* b ^* value. Detects sparse coordinate areas for which is not calculated. For example, the L ^* a ^* b ^* spatial data complementation unit 17 calculates a region where a coordinate value of the L ^* a ^* b ^* value exceeds “1” and is discontinuous, that is, an L ^* a ^* b ^* value. The L ^* a ^* b ^* value of the coordinate value while the distance of the non-coordinate is more than the distance is complemented. Detailed processing for this complementation will be described ^later, it calculates the mixing ratio of the L ^* a * ^{b *} values as discrete ^L * ^a * ^{b *} values. Here, the L ^* a ^* b ^* space data complementing unit 17 obtains the blending ratio with respect to the discretized L ^* a ^* b ^* value for which the blending ratio has already been obtained in the L ^* a ^* b ^* space. The blending ratio of non-discretized L ^* a ^* b ^* values is used as the calculation target.
The L ^* a ^* b ^* spatial data complementing unit 17 sets the discretized L ^* a ^* b ^* value for which the blending ratio has not been calculated as the target discretized L ^* a ^* b ^* value, and sets the target L Calculate the spectral reflectance that will be the ^* a ^* b ^* value.

That is, the L ^* a ^* b ^* space data complementing unit 17 instructs the spectral reflectance calculation unit 15 to use the blending ratio in the coordinate value at which the L ^* a ^* b ^* value adjacent to the L ^* a ^* b ^* value is calculated. Is output, and the complementary spectral reflectance is calculated. Then, the L ^* a ^* b ^* spatial data complementing unit 17 uses the complemented spectral reflectance calculated by the spectral reflectance calculating unit 15 to complement the L ^* a ^* b ^* calculating unit 16 as a predicted value L ^* a ^*. b ^* Calculate the value. The L ^* a ^* b ^* spatial data complementation unit 17 is a target discretization L given a complementation L ^* a ^* b ^* value that is a predicted value calculated by the L ^* a ^* b ^* calculation unit 16 and a supplemental blend ratio. It is determined whether the ^* a ^* b ^* value matches.

Here, the L ^* a ^* b ^* spatial data complementation unit 17 sets the coordinate value (the discretized L ^* a ^* b ^* that is the calculation target described later) that the complementation L ^* a ^* b ^* value gives the supplemental blend ratio ^. If a match within a predetermined error value) is previously set, the complementary ^L * ^a * ^{b *} values and ^L * ^a * ^{b *} values in this coordinate. Further, the L ^* a ^* b ^* spatial data complementing unit 17 additionally writes and stores the supplementary values in the blending ink table of the color gamut database 100 that can reproduce the supplementary values with respect to the blended ink data of the initial blending.
On the other hand, if the L ^* a ^* b ^* spatial data complementing unit 17 does not match the complement L ^* a ^* b ^* value with the coordinate value giving the complement blending ratio within a predetermined error set in advance, this complement L ^{* A *} b ^* value (discrete L ^* a ^* b ^* value to be calculated corresponding to the coordinates of the sparse area described later in the L ^* a ^* b ^* space) is changed. The above-described processing is repeated until they match within a predetermined error range.

Next, FIG. 7 is a flowchart showing an operation in creating a blended ink table of the color gamut database creating system 1 according to the present embodiment. Hereinafter, an operation example of the color gamut database creation system 1 according to the present embodiment will be described with reference to FIGS. 7 and 1.
Step S1:
The material setting unit 11 displays, for example, all types of base materials previously written in the material database 20 in order to allow the operator to select a base material that is the base of the blended ink generated by blending the base ink. A list is displayed at 18.
Then, when the operator selects any background material from the list display described above, the material setting unit 11 outputs the background identification information to the base ink selection unit 12 and the L ^* a ^* b ^* calculation unit 16. The process proceeds to step S2.

Step S2:
The base ink selection unit 12 selects base inks corresponding to the base material selected by the operator from the base inks stored in the base ink database 19 and displays a list on the display unit 18.
At this time, the base ink selection unit 12 classifies and displays them on the display unit 18 in a grouped state based on attribute data such as the type of tolerance data, transparency, and price.
The base ink selection unit 12 uses the base ink group selected by the operator as the base ink for blending the blended ink. Therefore, the base ink identification number of the base ink included in this group is combined with the combination design unit. 13 and the process proceeds to step S3.

Step S3:
When the base ink identification information of the base ink of the group selected by the operator is supplied, the combination design unit 13 mixes three types of color components and one type of dilution component, for a total of four types of base inks. Create a combination of.
At this time, the combination design unit 13 extracts the color of the base ink configured for each generated combination, determines whether the combination is a preset exclusion combination based on the extracted color combination, and excludes the exclusion ink. If the color combination is the same as the combination, the combination is removed and deleted.

  Then, the combination design unit 13 sequentially writes and stores the remaining combinations from which the excluded combinations have been removed, as blended ink sets that are combinations of base inks to be blended, in the blended ink table of the reproducible color gamut database 100, The process proceeds to step S4. In addition, the combination design unit 13 writes and stores the base material identification information of the base material selected by the operator in the column of the base material information in each of the current blended ink sets.

Step S4:
The initial blend setting unit 14 sequentially reads blended ink sets from the blended ink table of the reproducible color gamut database 100.
Then, the initial blending setting unit 14 varies the blending ratio indicating the blending ratio of the base ink of the read blended ink set according to a predetermined reference width, and blends with the blended ink blended at the blending ratio in the initial blending. Ink identification information and a color number are given, and are written and stored in the reproducible color gamut database 100. The initial blend setting unit 14 can reproduce the base ink identification information of the base ink used for blending the blended ink, the blend ratio, and the spectral reflectance as base ink information together with other attribute data. Write and store in the color gamut database 100 blended ink table. Then, the initial formulation setting unit 14 advances the process to step S5.

Step S5:
The spectral reflectance calculator 15 blends base ink information from the blended ink table of the reproducible color gamut database 100 to calculate the spectral reflectance of the blended ink corresponding to each blending ratio of the base ink in the blended ink set. Read in order of ink identification information.
Next, the spectral reflectance calculator 15 calculates the spectral reflectance of the blended ink from the blending ratio of each blended ink according to the formula (1) based on the blending ratio and spectral reflectance of each base ink in the read base ink information. To do.

Then, the spectral reflectance calculator 15 writes and stores the calculated spectral reflectance of each blended ink in the column of the blended ink spectral reflectance of each blended ink set in the blended ink table of the reproducible color gamut database 100. Let
When the spectral reflectance calculation unit 15 finishes calculating the spectral reflectance for all combinations of blending ratios in the blended ink set, the spectral reflectance calculation unit 15 calculates the L ^* a ^* b ^* value to the L ^* a ^* b ^* calculation unit 16. The control signal to instruct is output.

Next, the L ^* a ^* b ^* calculation unit 16 reads the color matching function and the spectral reflection intensity of the illumination when performing the spectral reflectance of the base ink from the base ink database 19, and the operator from the material database 20. Read the spectral reflectance of the selected base material.
Then, the L ^* a ^* b ^* calculation unit 16 sequentially reads the spectral reflectances of the blended ink set currently processed from the blended ink table of the reproducible color gamut database 100 in the order of blended ink identification information.

As a result, the L ^* a ^* b ^* calculation unit 16 in the order of reading, the spectral reflectance for each blending ratio, the read color matching function, the spectral reflection intensity of the illumination, and the background material selected by the operator. From the spectral reflectance, the L ^* a ^* b ^* value corresponding to the base material is determined for each blending ratio.
The L ^* a ^* b ^* calculation unit 16 associates the obtained L ^* a ^* b ^* values with the respective blended ink identification information, writes them in the blended ink table of the reproducible color gamut database 100, and proceeds to step S6. .

Step S6:
The spectral reflectance calculation unit 15 finishes calculating spectral reflectances for all ink combinations in the blended ink set in the blended ink table of the reproducible color gamut database 100, and performs processing for obtaining L ^* a ^* b ^* values. It is determined whether or not it has been completed.
At this time, the spectral reflectance calculation unit 15 advances the processing to step S7 when the processing for obtaining the spectral reflectance and the L ^* a ^* b ^* value is completed. On the other hand, the spectral reflectance calculation unit 15 advances the processing to step S4 when the processing for obtaining the spectral reflectance and the L ^* a ^* b ^* value is not completed.

Step S7:
Next, the L ^* a ^* b ^* space complementation unit 17 discretizes the real L ^* a ^* b ^* value calculated by the spectral reflectance calculation unit 15 in step S6 (for example, rounds off the value after the decimal point). The set of discretized L ^* a ^* b ^* values resulting from the discretization is set as a blending calculation target L ^* a ^* b ^* group, and the process proceeds to step S8.
FIG. 8 is a diagram for explaining the discretization performed by the L ^* a ^* b ^* space interpolation unit 17. In FIG. 8, the axis in the L ^* value direction is omitted, and a two-dimensional plane made up of the a ^* value and b ^* value axes is shown, but in actuality in the L ^* a ^* b ^* space. is there. FIG. 8A is a diagram in which L ^* a ^* b ^* values (calculated values) of ink blended initially at a predetermined blending ratio are plotted. FIG. 8B is a diagram in which the L ^* a ^* b ^* values of the blended ink are discretized and plotted as discretized L ^* a ^* b ^* values (discretized).

Step S8:
Then, the L ^* a ^* b ^* space interpolation unit 17 performs L ^* ± dL (ΔL), a for each of the discrete L ^* a ^* b ^* values included in the L ^* a ^* b ^* group to be blended. ^The discretized L ^* a ^* b ^* values obtained by ^* ± da (Δa) and b ^* ± db (Δb) are set as targets for the new blending calculation and added to the blending calculation target L ^* a ^* b ^* group. On the other ^hand, L ^* a * ^{b *} space complementation unit 17, a blending computation target ^L * ^a * ^{b *} discretization ^L * ^a * ^{b *} values blending computation excluded ^L * ^a * ^{b *} groups in the complement of the group Then, the process proceeds to step S9. Here, each of dL, da, db is a predetermined numerical value set in advance, and is “1” when the discretized numerical value is an integer value, for example.
Here, the L ^* a ^* b ^* spatial interpolation unit 17 is a discretized L ^* a ^* b ^* value obtained by performing L ^* ± dL, a ^* ± da, b ^* ± db in the L ^* a ^* b ^* group to be blended. In FIG. 5, the discretization L ^* a ^* b ^* values that are already in the L ^* a ^* b ^* group and are overlapped are deleted.

FIG. 9 is a diagram for explaining the setting of the discretized L ^* a ^* b ^* values included in the composition calculation target L ^* a ^* b ^* group to be calculated. FIG. 9 is similar to FIG. 8 except that the axis in the L ^* value direction is omitted, and shows a two-dimensional plane composed of the a ^* value and b ^* value axes, but in actuality L ^* a ^* b ^* Space. FIG. 9 (a) shows the discrete L ^* a ^* b ^* values (calculation targets) for the blending calculation target, and the discrete L ^* a ^* b ^* values for the blending calculation target are L ^* ± dL, a ^*. It is the figure which set the discretization L ^* a ^* b ^* value (new object) which carried out +/- da and b ^* + /-db.

Step S9:
The L ^* a ^* b ^* space complementation unit 17 evaluates the connection between the L ^* a ^* b ^* group subject to the blending calculation and the L ^* a ^* b ^* group not subject to the blending calculation.
Here, the L ^* a ^* b ^* space complementing unit 17 connects (adjacent) the discrete L ^* a ^* b ^* values in the blending calculation target L ^* a ^* b ^* group and the blending calculation target. The number of groups is evaluated by grouping the L ^* a ^* b ^* values in the outer L ^* a ^* b ^* group. FIG. 9B is a diagram showing a grouping result of a blending calculation target L ^* a ^* b ^* value (calculation target) and a non-calculation L ^* a ^* b ^* value (not calculation target). In FIG. 9B, there are a plurality of groups of L ^* a ^* b ^* values that are not subject to calculation.

That is, the L ^* a ^* b ^* space complementing unit 17 moves the discrete L ^* a ^* b ^* values in the L ^* a ^* b ^* group within the L ^* a ^* b ^* group in the L ^* a ^* b ^* space up and down (in the L-axis direction). ) before and after (a-axis direction) lateral (b axis) formulated calculated in 6 direction of the target ^L * ^a * ^b other discretization ^L * a ^* in the group ^a * ^{b *} discretization is linked to the value ^L * a Count the number of groups consisting of ^* b ^* values.
Similarly, the L ^* a ^* b ^* space complementing unit 37 has the discrete L ^* a ^* b ^* values in the L ^* a ^* b ^* group not included in the blending calculation target in the L ^* a ^* b ^* space, up, down, front, back, left, and right. counting the number of groups of discrete ^L * ^a * ^{b *} values in the six directions are connected to the other discrete ^L * ^a * ^{b *} values of compounding calculations exclude ^L * ^a * ^{b *} within the group.

Step S10:
Next, the L ^* a ^* b ^* space complementation unit 17 includes a group of discrete L ^* a ^* b ^* values in the blending calculation target L ^* a ^* b ^* group, and a blending calculation non-target L ^* a ^* b. ^* Determine whether each discrete L ^* a ^* b ^* value group in the group is one.
In this ^case, L ^* a * ^{b *} space complementation unit 17, the mixing calculation target ^L * ^a * ^{b *} each discretized in the group ^L * ^a * ^{b *} and a group of values, blending computation excluded ^L * ^a * b ^{* If} each of the discrete L ^* a ^* b ^* value groups in the group is one, the process proceeds to step S11. Here, FIG.9 (c) is a figure which shows the grouping result of mixing | blending calculation object L ^* a ^* b ^* value and non-calculation object L ^* a ^* b ^* value. In FIG. 9 (c), one group of the composition calculation target L ^* a ^* b ^* value (calculation target) and the non-calculation L ^* a ^* b ^* value (non-target) is configured. .
On the other ^hand, L ^* a * ^{b *} space complementation unit 17, the mixing calculation target ^L * ^a * ^{b *} each discretized in the group ^L * ^a * ^{b *} a group of values, or compounding calculations exclude ^L * ^a * ^{b *} If there are two or more in any one of the groups of the discrete L ^* a ^* b ^* values in the group, the process returns to step S8.

Step S11:
The L ^* a ^* b ^* space complementation unit 17 obtains the blending ratio of the base ink for obtaining a discretized L ^* a ^* b ^* value as a new blending calculation target.
At this time, the L ^* a ^* b ^* space complementation unit 17 uses an initial blending ratio set in advance as an initial value of the blending ratio in the calculation of the blending ratio of each of the discretized L ^* a ^* b ^* values to be newly blended. And a blending ratio corresponding to the discrete value is calculated. Here, the initial blending ratio is arbitrary, and when three types of base inks are used, they may be set to 34%, 33%, 33%, etc., for example.
Further, the L ^* a ^* b ^* space complementation unit 17 discretizes the predicted L ^* a ^* b ^* value obtained as a result of the blending ratio in the blending ratio calculation process.

Then, the L ^* a ^* b ^* space interpolation unit 17 confirms whether the discretized predicted L ^* a ^* b ^* value matches the blending calculation target L ^* a ^* b ^* value that is the target value, and blended calculated ^L * ^a * ^{b *} values if they match, in addition to calculated ^L * ^a * ^{b *} group, and excluding from the formulation calculated target ^L * ^a * ^{b *} group.

FIG. 10 is a diagram for explaining processing for calculating a blending ratio of discretized L ^* a ^* b ^* values included in the L ^* a ^* b ^* group that is not blending calculation target. 10 (a) is discretized is a blended calculation object in FIG. ^{9 (c) L * a *} b * is calculated to determine the mixing ratio does not converge in value, which is a blended calculation object discretization L ^* a ^* b ^* values ^{(e.g., a * = 24, b *} = 21 discrete ^L * ^a * ^{b *} values etc.) is that once again, is the discretized ^L * ^a * ^{b *} value outside the mixing calculation object FIG. FIG. 10A shows only the discretized L ^* a ^* b ^* values (calculated) in which the calculation of the blending ratio is converged.

Step S12:
Then, the L ^* a ^* b ^* space complementation unit 17 performs L ^* ± dL, a ^* ± da, for each of the discrete L ^* a ^* b ^* values included in the calculated L ^* a ^* b ^* group. Discrete L ^* a ^* b ^* values that do not overlap with the discrete L ^* a ^* b ^* values in the calculated L ^* a ^* b ^* group in the b ^* ± db discrete L ^* a ^* b ^* values Add to the L ^* a ^* b ^* group for calculation.

Step S13:
Next, the L ^* a ^* b ^* space interpolation unit 17 performs blending on the newly set discretized L ^* a ^* b ^* value of the new blending calculation target in the blending calculation target L ^* a ^* b ^* group. Recalculate the ratio.
At this time, the L ^* a ^* b ^* space complementing unit 17 uses the one having the smallest color difference in the blended L ^* a ^* b ^* group as the initial value of the blending ratio. Here, when the same color difference exists, any of them may be set as the initial value. For example, a priority order is set in advance in the order of L ^* value, a ^* value, and b ^* value.
Then, the L ^* a ^* b ^* space complementing unit 17 within the range of the number of operations set in advance, the discretized predicted L ^* a ^* b ^* value and the blending calculation target L ^* a ^* b ^* that is the target value ^. check the discretization ^L * ^a * ^{b *} values in the group matches, the discretized ^L * ^a * ^{b *} values of the formulations calculated if they match, the formulation calculated ^L * ^a * ^{b *} group include.

Step S14:
L ^* a ^* b ^* space completion unit 17, in step S13, blending Calculated ^L * ^a * ^{b *} discretized newly included in the group ^L * ^a * ^{b *} values, already formulated Calculated ^L * ^{a *} If there is a numerical value that matches one of the discretized L ^* a ^* b ^* values included in the b ^* group, the process returns to step S12.
On the other hand, in step S13, the L ^* a ^* b ^* space complementation unit 17 has already added the compounded L ^* a ^* b ^* values included in the compounded L ^* a ^* b ^* group to the compounded L ^*. If it does not match any of the discretized L ^* a ^* b ^* values included in the a ^* b ^* group, the process ends. FIG. 10 (c), the re-calculation results in not converge discretized ^L * ^a * ^{b *} value (Calculated), discretization ^L * ^a * ^{b *} value outside the calculation object is a discrete color gamut It is a figure which shows that it became the conversion L ^* a ^* b ^* value (outside the color gamut).

As described above, according to the present embodiment, the discretization L ^* a ^* in the L ^* a ^* b ^* color space corresponding to the background material selected by the operator and the attribute data such as the tolerance data and the price ^. b ^* value is calculated so that there is no sparse area in L ^* a ^* b ^* color space (area where the density of coordinate values not calculated as L ^* a ^* b ^* value is low), that is, color continuity However, the discretized L ^* a ^* b ^* value as color gamut data that is higher than in the past can be easily complemented.
Thus, according to the present embodiment, a state where a discrete L ^* a ^* b ^* value in a reproducible color gamut is connected to another adjacent discrete L ^* a ^* b ^* value, that is, a sparse region is obtained. Since there is no state, it is possible to obtain a blending ratio that corresponds to the reproduced color with high accuracy, and the type of base ink that reproduces the color corresponding to the background material to be colored, which the designer desires, and those It is possible to create a database that can easily determine the blend ratio of the base ink.

Further, according to the present embodiment, a group of base inks is formed based on the availability and useable area which is one of the attribute data, and the blending color is determined based on the base ink which can be easily obtained and used in the area where the designer works. Color gamut data can be obtained, and the work efficiency of the designer can be improved.
Furthermore, even in the color product manufacturer, the color specified by the color determiner is reproducible with the material used in the product, and since the combination of the base ink used for color reproduction and the initial composition are known, The color matching work can be made efficient.

  Further, a program for realizing the function of the color gamut database creation system in FIG. 1 is recorded on a computer-readable recording medium, and the program recorded on the recording medium is read into the computer system and executed to execute the database. Creation processing may be performed. Here, the “computer system” includes an OS and hardware such as peripheral devices.

Further, the “computer system” includes a homepage providing environment (or display environment) if a WWW system is used.
The “computer-readable recording medium” refers to a storage device such as a flexible medium, a magneto-optical disk, a portable medium such as a ROM and a CD-ROM, and a hard disk incorporated in a computer system. Furthermore, the “computer-readable recording medium” dynamically holds a program for a short time like a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line. In this case, a volatile memory in a computer system serving as a server or a client in that case, and a program that holds a program for a certain period of time are also included. The program may be a program for realizing a part of the functions described above, and may be a program capable of realizing the functions described above in combination with a program already recorded in a computer system.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and includes design and the like within a scope not departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Color gamut database creation system 11 ... Material setting part 12 ... Base ink selection part 13 ... Combination design part 14 ... Initial mixture setting part 15 ... Spectral reflectance calculation part 16 ... L ^* a ^* b ^* value calculation part 17 ... L ^{* A *} b ^* Spatial data complementing part 18 ... Display part 19 ... Base ink database 20 ... Material database 100 ... Reproducible color gamut database

Claims (5)

A base ink selection section for selecting a base ink used for preparing the blended ink according to a preset selection condition;
A combination design unit for setting a combination group of the base inks of a plurality of different colors for adjusting the color of the combination ink;
An initial blend setting unit for setting the blend ratio of each of the base inks in the blend group;
Spectral reflectance calculation unit for obtaining the spectral reflectance of the blended ink by the blending group for each blending ratio,
A coordinate value calculation unit for obtaining a coordinate value of the color of the blended ink in a predetermined color space from the spectral reflectance, and
The coordinate value, the blending group, the blending ratio, the spectral reflectance, and the selection condition are associated with each other and written to an external color gamut database. The coordinates adjacent to the no-data coordinate position are detected in order to detect an area where the coordinate value is sparse in the color space and complement the no-data coordinate position where the coordinate value is not obtained in the area where the coordinate value is sparse. While changing the blending ratio of the value, let the spectral reflectance calculation unit calculate the spectral reflectance in the changed blending ratio, let the coordinate value calculation unit calculate the coordinate value from the spectral reflectance, 2. The color according to claim 1, further comprising: a spatial data complementing unit that obtains the blending ratio of the coordinate values to be a no-data coordinate position and complements coordinate values of a sparse area in the color space. Area database creation system. It further has a material setting unit for selecting a base material to be colored with the blended ink,
The coordinate value calculation unit
The color gamut database creation system according to claim 1 or 2, wherein the coordinate value is calculated using a spectral reflectance of the base material in addition to a spectral reflectance of the blended ink. The coordinate value calculation unit
4. The coordinate value is calculated using spectral characteristics of a light source that illuminates a colored product colored with the blended ink in addition to the spectral reflectance of the blended ink. The described color gamut database creation system. A base ink selection process for selecting a base ink to be used for preparing a blended ink according to a preset selection condition;
A combination design process for setting a combination group of the base inks of different colors for adjusting the color of the combination ink;
An initial blend setting process for setting the blend ratio of each of the base inks in the blend group;
Spectral reflectance calculation process for obtaining the spectral reflectance of the blended ink by the blending group for each blending ratio,
A coordinate value calculation process for obtaining a coordinate value of the color of the blended ink in a predetermined color space from the spectral reflectance,
A color gamut database creation comprising: a data writing process that associates the coordinate values, the blending group, the blending ratio, the spectral reflectance, and the selection condition, and writes the data to an external color gamut database. Method.

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