JPS62179056A - Color graphic simulation device - Google Patents

Abstract

PURPOSE:To guarantee consistency between a color displayed with a display device, and the color printed with a printer device, by selecting exactly the color nearest to a given color chip out of the number of comparatively few kinds of colors limited by the number of dots at a unit coloring area in a color printer device. CONSTITUTION:A file 10 is constituted with plural sheets of records 11 having an area where the values of R, G, and B to be supplied to a lightness index L*, chromaticness indexes a* and b*, and a display device 2, and the values of Y, M, C, and (Bk) to be supplied to a printer device 3, are registered. A color information reading device 5 can read the color of a requested area on an original B as the lightness index L*, and the values of the chromaticness indexes a* and b*. And the color information reading device 5 and the file 10 are linked so that a color difference between the color decided by L*, and the values of a* and b* outputted from the reading device 5, and the color registered in the record 11 becomes minimum, through a retrieving means 6 which retrieves the record 11 in the file 10.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a color graphic simulating device used when comparing and examining various designs with different color schemes prior to deciding on a color design.

For example, prior to deciding on the textile design, candidates B0, Bbl, Bc of color charts to be colored in the unit pattern A and each colored area a, bXc of pattern A as shown in FIG.
1, Ba2, Ba1l, and BC2 are presented, and when the repeated arrangement state of the units on the pattern is changed, the colors of the colored areas a, b, and c for each of them are shown in the color chart Bs I to 13cz. You may be asked to submit samples of different combinations.

Previously, in cases like this, a single sample of the original drawing was colored by hand, but this process had to be repeated many times before finalizing the design, which was extremely time-consuming. Since this is a complicated and time-consuming task, color graph ink simulators using electronic computers have come to be used.

1. Prior Art - This type of color graphic simulator is equipped with a document reading device such as a drum scanner, a color display device typified by a color CRT, and a color printer using a thermal transfer method, a wire dot impact method, an inkjet method, etc. , a document is read and displayed on a display device, and a design with a changed color scheme is displayed on the display device by operating keys or dials, and a sample can be printed out on a printer as necessary.

However, as is well known, the color development of a color display device is obtained by adjusting the brightness of R (red), G (green), and B (blue) dots, and the color development of a color printer is set to, for example, 4 x 4 = 16 dots. Y (yellow), M (magenta), C (cyan) or Y in the unit coloring area.

M, C, Bk (blank) (the latter four colors are common.Hereafter, both are collectively referred to as Y, M, C1 (B
k). ) They are obtained by arranging dots of each color and have different coloring principles. However, even if the same RlG, H luminance signals or Y, M, C, (Bk) dot arrangement signals are given, it may vary depending on the type of display device or printer device, or the ribbon attached to the printer device. There may be slight differences in color development depending on the type of ink used. Therefore, problems commonly occur in which the colors displayed on the display device are different from the colors of the original, and the colors printed by the printer are different from the colors of the original and the colors displayed on the display.

One way to solve this problem is to transfer the color signals read by a drum scanner, etc. to the R, G, and B signals of the display device.
It attempts to correct by inserting various correction terms into the conversion formula for converting into signals and the conversion formula for converting the R1G, B signals into Y, M, C1 (Bk) signals of the printer device. It is used in color printing plate-making equipment that requires changes in gradation, but the equipment is extremely large, complex, and expensive, and setting correction parameters requires a huge amount of data and skilled work. It is difficult to apply it to graphic devices.

Another method for solving the above problem is, for example,
As described in Publication No. 6403, the input R
, G, and B signals to be output corresponding to each set of combinations obtained by changing the values of each signal at regular intervals,
The M and C signals are registered in the memory in advance, and the R, G, and B signals actually input by the drum scanner are individually A-
D conversion and rounding to the above fixed interval, and the converted R, G
, B signals are used as address signals to read the Y, M, and C signals from the memory.

-Problems to be Solved by the Invention- By extending the latter method, it is possible to register the R, G, B (i) signals to be given to the display device along with the Y, M, and C signals. (Generally, the R50SB signal to be applied to the display device and the R, GSB signal to be given to the display device do not match.), the color of the original in the color graphic simulator, the color displayed on the display device, and the color printed by the printer device can be easily matched. However, R, G.

Even if each of the B signals is changed at regular intervals, the color difference perceived by the human eye between the resulting colors is not constant. Therefore, if a memory is to be configured using the above method, the intervals between the R, G, and B signals, which serve as addresses, must be determined based on the area where color differences are most sensitive to the human eye, and each signal As the number of gradations increases, it becomes necessary to increase the memory capacity.

Furthermore, a color that is perceived to be more similar to that obtained by a combination of completely different R, G, and B signals may be produced than a color obtained by a combination of adjacent R, G, and B signals. In the above method of addressing the memory by comparing the R, G, and B signals individually, there is no guarantee that the optimal registration data is selected.

Furthermore, as the number of required gradations of R, G, and B signals increases, a problem arises in relation to the number of dots in the unit coloring area of the printer device. For example, if it becomes necessary to divide the R signal into 64 gradations at equal intervals in order to produce a color that is recognized as the same as the original in the area where color differences are most acutely perceived by the human eye, the printer device The unit color development area must be 8×8=64 dots. However, as the unit coloring area becomes larger, the width of the printed colored lines becomes wider, causing problems such as diagonal lines and curved lines becoming jagged lines, and problems with the uniformity of colors displayed on the colored surface. It comes out. From the printer's perspective, it is desirable that the unit coloring area be approximately 4 x 4 = 16 dots, but in the conventional method described above, if the R, G, and B signals are each approximately 17 (16+1) gradations, It becomes impossible to express colors that match the original.

This invention was made with the aim of solving the above-mentioned problems of the prior art, and uses color signals with fewer gradations, which are limited by the size of the unit coloring area of the printer, to match the colors of the original. The colors displayed on the display device and the colors output from the printer device can be matched with each other, and desired color signals can be arbitrarily removed or added depending on the degree of color difference visually recognized by the human eye. The purpose is to obtain a color graphic simulating device that can

Means for Solving a Problem - The present invention is directed to an electronic color graphic simulator comprising a color display device 2 and a color printer device 3 as shown in FIG. The printer device 3 may be of any type such as a thermal transfer type, a wire dot impact type, or an inkjet type, but it can print Y, M, C, (Ilk) in a coloring area of a predetermined unit.
) The gradation of each color is expressed by the number of dots.

The apparatus of the present invention has a storage device 4 in which files 10 as shown in FIG. 2 are registered. The file 10 includes, for example, the lightness index L1 and chromaticness index a*, bo in the L08″jbI color system, and the display device 2.
R,G to be given to.

B value and Y, M, and C to be given to the printer device 3.

(Bk) and a plurality of records 11 having areas for registering values. A minimum of (n+1)' records 11 are prepared, assuming that the number of dots set in the unit coloring area of the printer device 3 is n.

The apparatus of the present invention also includes a color information reading device such as a spectrophotometer or a photoelectric colorimeter 5, and the reading device 5
The color of a desired area (for example, color chart B□) of the document B can be read as, for example, the lightness index L9 and the chromaticness index a" and b1 values in the L"as be color system. As a color system, L”a * b
In addition to the 's color system, the L"u"vlT color system, the Lab color system, and the like are known, but the essence of the present invention does not change no matter which color system is used. Hereinafter, these color systems will be described using the L*a*b (1 color system) as a representative color system.

Note that the color information reading device 5 may itself directly output the ri'', a'', and b'' values in a predetermined color system, and convert the output to L'''.
, a*, b* values may be obtained.

Each record 1 of the file 10 has corresponding L*, a9, b0 values, R, G, B values, and Y, M, C1 (
Bk) value is registered. That is, the L"%a", b" values, R,
G, B value and Y.

M, C, and (Bk) values are registered as a set in one record 11.

The color information reading device 5 and the file 10 display the colors output from the reading device 5 and the colors determined by the ", a", b'" values and the L", a" registered in the record 11.
, b" search means 6 for searching the record 11 in the file 10 such that the color difference from the color determined by the value is minimized.
connected via. If it is L″a″b′″ color system,
The color difference ΔE between the two colors is ΔE=(ΔL42+a#2+
Since it is given by bi)Z)I/Z, the record 11 in which the L″, a″, and b7 values for which this ΔE is the minimum is registered is searched. Here, ΔL8, Δam, Δb9
are the read L", a", b" values and l/D-1
This is the difference between the L'', a'', and b'' values registered in 'll. This search means 6 is generally constituted by software (program). G, B value and y, M, C1
The (Bk) value is controlled to be provided to the display device 2 and printer device 3, respectively.

-Effect- Bi, a m, for each receipt 11 of the file 10
b The registration procedure for the $ value, R, G, B value, and Y, M, C, (Bk) value is performed as follows.

For example, if the number of dots in the unit coloring area of the printer device is set to n, the Y, M, and C values are divided equally into n+1 gradations including white (no color dot imprinting), and the total Register all combinations in file 1o. Y, M, and C that can be printed by the printer device 3.

(Bk) Since the gradation of each color is determined by the number of dots within the unit coloring area, the Y, M, C, and (Bk) values are registered in the record 11 as integer values from 0 to n. Then, the registered data is retrieved and a color chart corresponding to each record 11 is printed by the printer device 3, and the color chart is read by the color information reading device 5 and the L", a", b” value is registered.

Next, L'', a of each record 11 is calculated using a known theoretical formula.
", calculate the R, G, B values corresponding to the b9 value and temporarily register them in the record 11. Then, the temporarily registered RlG, B
Call the value and display the color on the display device 2,
It is compared with the corresponding color chart previously printed out by the printer device 3. If there is a color difference between the two, manually correct the color displayed on the display device 2 until there is no longer a color difference between the two, and when the corrected color is displayed on the display device 2. given R
The IG and B signal values are replaced with the temporarily registered R, G and B signals and registered in the corresponding record 11. The Lll, aI, and b* values are set by reading the color chart as described above, and R, G, and
It is not necessary to correct the B value for all records in file 10; select a representative record appropriately and perform it only for that record. For other records, use an appropriate complementation method (for example, linear completion). ) to register and modify the data.

When a predetermined number of records are registered in the file 10 in this way, the display device 2 and the printer device 3 are given signals only from the file 10 except during manual operation, and colors that are not registered in the file IO are given signals to the display device 2 and the printer device 3. cannot be displayed or typed out. Therefore, when a hard copy of the design displayed on the display device 2 is printed out by the printer device 3, Y, M, and C1 (Bk) signals are given to the printer device 3 from the record 11 containing the selected R, G, and B signals. Therefore, consistency between the printed color and the color displayed on the display device 2 is guaranteed.

In addition, when designing based on a given color chart, records with L''', a'', b'' values that have the smallest color difference from the color of the color chart are selected for R, G, B signals and Y, M. ,,C
, (Bk) signals are given to the display device 2 and the printer 3, so that the closest color that can be printed by the printer device 3 is displayed on the display device 2, and is also printed from the printer 3. In the present invention, the R, G, B signals given to the display device and the Y, M, C, (Bk) signals given to the printer device are the same as the lightness index L9 and chromaticness index a'', bl in a predetermined color system. The registered Ll, a′″, b
“Since the value is used to search for the registered color that has the smallest color difference from the color chart, it is possible to extract the registered color that the human eye would confuse as the closest color.

One Embodiment - In one preferred embodiment of the present invention, the color signal reading device 5 is a photoelectric colorimeter that outputs color tristimulus values X, Y, and Z defined by CIE (Commission Internationale de Illumination). The output signals X, Y, and Z are sent to the central processing unit 1.
Lm aI b *Lightness index L'' and chromaticness index a'', b'' in color difference system are calculated using a known conversion formula.
get. The color printer device 3 includes Y, M, C and B.
An inkjet printer using four colors of ink is used, and the dot density of the printer 3 is 12 dots/mm.
An area of 4×4=16 dots is set as a unit coloring area. Therefore, the number of gradations of each color Y, M, and C that can be displayed by the printer device 3 is 17 gradations including white (no dots of the color), and the record 11 prepared in the file 10 of the storage device 4 The minimum number of sheets is 17" = 4913, but including spares 243 =
The number of sheets is 13,824.

There are four types of signals registered in the file 10 as signals given to the printer device 3: Y, M, C, and Bk. Here, the registration area of the Bk signal includes the combined Y, M
, the value corresponding to the minimum gradation among the C values is registered, and the value corresponding to the minimum gradation among the Y,
In the M and C registration areas, a value obtained by subtracting the Bk value from the original gradation value is registered. That is, each color of Y, M, and C is 1
For the color given in 2.5.3, Bk=3, Y=
9. Y, M, C, and Bk values are registered with M=2 and C=O.

Here, the values to be registered are only the three colors Y, M, and C, and when giving the values to the printer device 3, the Bk
It is also possible to configure the conversion into Y, M, C, and Bk values including the above, but in this case, it becomes impossible to register additional colors by changing the Bk value, which will be described later.

For the 4913 records having the Y, M, C, 'Bk values set in this way, the L
ll, a*, be values and R, G, B values are registered.

After the record 11 is registered as described above, the relationship between the display colors of the color display device 2 and the color printer device 3 and the color of the document B read by the photoelectric colorimeter 5 is as described above. Sufficient color identity is ensured as a color graphic simulator for textile design.

In the registration of the file 10 described above, for example, Y, M
, Y, M for the color displayed with a C value of 12.5.3.
, C and Bk values were 9.2 and O13. However, since the colors of ink and ink ribbon actually used deviate from the ideal colors, Y and M, which ideally should be the same color,
, C, Bk values of 10.3, ■, and 2 are printed by the printer device t3, the reality is that there is a color difference between the two. Therefore, for example, if a color difference is recognized between the color printed by the printer device 3 as a color corresponding to a certain color chart and that color chart, the distribution of Bk values of the selected record is changed (for example, as described above). Y, M, C, B
7% M from k-9,2,0,3.

C, Bk = 10.3.1, 2) If the color is the same as the color on the color chart, then the Y, MSC
, Bk value is added to file 10.

Records added in this way are selected using the same procedure as the first record, so in subsequent operations, the color with the smallest color difference is selected from among the colors that include the color of the added record. It will be done.

- Effects of the Invention - As described above, the device of the present invention selects the color closest to a given color chart from among a relatively small number of colors limited by the number of rollers in the unit coloring area of a color printer device. can be accurately selected and applied to the display device and the printer device, while also ensuring consistency between the colors displayed on the display device and the colors produced by the printer device. Furthermore, it is possible to register additional intermediate colors with subtle color differences, and colors can be registered and selected using the same standards as the color differences perceived by the human eye, so it is relatively small-scale and rigorous. An optimal device can be obtained as a color graph ink simulator that requires color consistency.

[Brief explanation of drawings]

Figure 1 is a conceptual diagram showing the basic configuration of this invention, Figure 2 is a conceptual diagram showing data registered in a storage device, and Figure 3 is an example of a manuscript with a design simulated by a color graphic simulation device. It is a diagram. In the figure, ■ = central processing unit 2: color display device 3: color printer device 4: storage device 5: photoelectric colorimeter/(color information reading device) 6: search means 10: file 11 2 records

Claims (1)

[Claims] In an electronic color graphic simulator equipped with a color display device and a color printer, a color difference element signal consisting of a brightness index and two chromaticness indexes in a predetermined color system, and a color display when the element signal is given. R, G, B signals to be provided to the device and Y, M, C or Y, M, C, B to be provided to the color printer device when the element signals are provided.
a storage device in which a plurality of sets of data each including a k signal are registered; a means for reading color information on a document as color information consisting of a brightness index and two chromaticness indices in the predetermined color system; Means for searching the registered data for a set having an element signal that has the smallest color difference from the color information retrieved, and R, G, B signals and Y, M, C or Y registered in the searched set. , M, C, and Bk signals to a color display device and a color printer device, respectively.