JP2005208982A - Monitor profile generation system, program and recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a monitor profile generation system, etc. easily generating a monitor profile for performing accurate correction according to a display characteristic of each monitor. <P>SOLUTION: A monitor characteristic measurement apparatus 101, being connected to a monitor 207 for measurement, displays on the monitor 207 each processing screen for measuring a display characteristic of the monitor. In 'Selection of a monitor type', a chromaticity of RGB primary colors depending on the type of the monitor 207 is set; in 'Adjustment of the tone', a tone regeneration characteristic of the RGB primary colors is measured with achromatic gradation through visual observation or using a measurement device 105; in 'Adjustment of chromaticity of the white color', colorimetry of the reference white concerned is performed under a predetermined lighting environment through visual observation or using the measurement device 105, and the chromaticity of the white color is measured; and in 'Generation of a profile', a monitor profile 302 is generated and retained from the measurement result data. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a monitor profile creation system for creating a monitor profile by measuring and adjusting tone reproduction characteristics, white chromaticity, etc. in a color monitor.

  Generally, a monitor (display device) has different display characteristics for each product, and when connected to a personal computer or the like, it is preferable to perform correction according to each display characteristic. In order to perform such correction, it is necessary to measure the display characteristics of individual monitors in advance and prepare the results as objective data. Usually, such data is called individual monitor profile data. When using a monitor connected to a personal computer, if the profile data of the monitor is incorporated in the personal computer, correction based on this profile data is possible, and it is universal regardless of the display characteristics unique to each monitor. Display results can be obtained.

Typical display characteristics of a color monitor having a function of displaying a color image using the three primary colors RGB are the chromaticity of the three primary colors, the chromaticity of white, and the gradation reproduction characteristics. Here, the gradation reproduction characteristic is a characteristic indicating the relationship between the input signal gradation value and the actual display luminance, and is usually called a gamma characteristic. If correction according to the gradation reproduction characteristics is not performed, even if display is performed based on exactly the same image data, image display with a different luminance distribution is performed for each monitor. Therefore, in practice, it is a very important matter to perform correction (so-called gamma correction) according to the tone reproduction characteristics unique to each monitor. For example, Patent Document 1 below discloses a general method for such gamma correction.

  As a method of measuring the gradation reproduction characteristics of each monitor, there is a method of obtaining physical characteristic data using an optical measuring device, but usually the characteristic data is obtained while visually observing with human eyes. The technique to obtain is taken. This is because characteristics are obtained by a measurement method based on human visual perception rather than characteristic data obtained by a pure physical measurement method because the monitor is only used by humans. This is because the data is preferable. For example, Patent Document 2 below discloses a method for obtaining gradation reproduction characteristics by visual observation.

  Further, the white chromaticity is obtained as a gradation value of the three primary colors RGB necessary for causing each color monitor to perform white display. If an application program running on a personal computer wants to display white on the monitor, it can perform the process of giving to the monitor the gradation values of the three primary colors RGB determined as the white chromaticity. Good.

  The white chromaticity can be obtained by physical measurement using an optical measuring instrument, and the white chromaticity measured at the time of shipment is attached to a general commercial color monitor as monitor profile data. Often done. Recently, there has also been proposed a method for obtaining white chromaticity by incorporating a dedicated program into a personal computer or the like connected to a monitor without using a special measuring instrument. For example, Patent Document 3 below discloses a method for measuring white chromaticity by visual observation by an operator.

  Further, in the conventional general procedure for creating a monia profile, first, the number of gradation reproduction characteristic measurement points is determined. The number of gradation reproduction characteristic measurement points may be determined in advance. Next, the white point and RGB primary colors are measured. Further, the red (R), green (G), and blue (B) single color patches are measured by the number of measurement points. Finally, a monitor profile is created based on the color measurement result.

Japanese Patent Laid-Open No. 07-162714 Japanese Patent No. 2889078 JP 2000-029444 A

  As described above, it is very important to obtain the gradation reproduction characteristics for each monitor by visual observation, but it is very important for correction that matches the sensitivity characteristics of human eyes. There is a problem that the method and the measuring apparatus cannot obtain gradation reproduction characteristics with sufficient accuracy. In particular, in the case of a color monitor used for DTP processing for creating a printed matter, it is necessary to obtain a more accurate gradation reproduction characteristic and perform correction with higher accuracy. Therefore, it is difficult to measure with sufficient accuracy for a CRT color monitor that has changed over time.

  In a monitor in which additive color mixture is established, if the chromaticity and gradation reproduction characteristics of the RGB primary colors are known, the colorimetric value can be predicted from the RGB values. From this principle, it can be seen that when the gradation reproduction characteristics of the three primary colors are calibrated together, the chromaticities of the RGB equivalent amounts of achromatic colors (white to gray to black) are all the same. For example, the xy chromaticities of (RGB) = (255, 255, 255), (128, 128, 128), and (0, 0, 0) are the same. It has been found that additive color mixing is well established for CRT monitors.

However, additive color mixing is not realized in the liquid crystal monitor. FIG. 35 shows a color reproduction principle 700 of a liquid crystal monitor. The liquid crystal monitor displays colors by the mechanism shown in FIG.
First, the backlight emits light. For the backlight, a cold cathode tube or a light emitting diode is used. Next, the light from the backlight passes through the liquid crystal shutter. Since the liquid crystal shutter can change the transmittance according to the applied voltage, the light emission intensity can be changed by changing the transmittance of the liquid crystal shutter. The light transmitted through the liquid crystal shutter emits light in three colors by passing through the RGB color filters.

  With such a mechanism, the liquid crystal monitor emits light, but the liquid crystal shutter has a problem that not only the transmittance but also the chromaticity is changed depending on the transmittance. Specifically, it has a characteristic that the bluish color becomes stronger as the transmittance decreases. For this reason, the chromaticity of the three primary colors RGB changes according to the gradation value. The monitor profile created by the conventional method is created on the premise that the chromaticity of the three primary colors of RGB is invariant regardless of the gradation value. Therefore, the chromaticity obtained when emitting light by giving an RGB value to the monitor is calculated between the expected value calculated using the monitor profile created by the conventional method and the measured value obtained by actual measurement. There was a problem that the difference became large.

  In addition, as described above, if monitor profile data indicating white chromaticity is prepared for each monitor and the white display characteristics are corrected based on the profile data, the display characteristics specific to each monitor are affected. It becomes possible to perform a universal white display that is not performed. However, the conventional profile data indicates the physical white display characteristics of each monitor itself, and does not indicate the visual characteristics seen by the operator when the monitor is placed in a specific lighting environment. . Therefore, for multiple color monitors used in the same lighting environment, if white display characteristics are corrected using monitor profile data indicating white chromaticity measured by the conventional method, almost the same white reproduction However, the same white reproducibility cannot be obtained for a plurality of color monitors used in different illumination environments. This is a big problem in practical use.

  For example, in a DTP process for creating a commercial print, it is common for many staff members to proceed with work assigned to each while looking at a color monitor. However, the lighting environment of the room where each staff works is not necessarily the same. For example, the working environment of an editor inside a publishing company is usually different from the working environment of a designer at an external design office. Specifically, each lighting environment varies greatly depending on conditions such as whether the indoor lighting is a fluorescent lamp or a light bulb, the color of the indoor wallpaper, whether sunlight is inserted, or the like. In such a case, even if correction is performed based on the white chromaticity (pure white chromaticity for each monitor) measured by the conventional method, the white hue that each staff member visually observes on the monitor is different from each lighting environment. It becomes different under the influence of.

  The present invention has been made in view of the above points, and an object thereof is to provide a monitor profile creation system that easily creates a monitor profile that performs high-accuracy correction according to the display characteristics of each monitor. To do.

In order to achieve the above object, a first invention is a system for creating a monitor profile comprising a terminal device connected to a color monitor having a function of displaying a color image using the three primary colors RGB, RGB primary color chromaticity setting means for setting chromaticity of RGB primary colors according to the type of monitor, and gradation reproduction characteristic measurement for measuring gradation reproduction characteristics of RGB primary colors based on display luminance and gradation values of the color monitor Means,
White chromaticity measuring means for measuring the white chromaticity of the color monitor, and a monitor that creates and holds a monitor profile from data such as chromaticity of the RGB primary colors, gradation reproduction characteristics of the RGB primary colors, and white chromaticity And a profile creation means.

The gradation reproduction characteristic measuring means preferably measures the gradation reproduction characteristic visually or using a measuring instrument.
The white chromaticity measuring means preferably selects a reference white color, measures the color of the reference white color under a predetermined illumination environment by visual observation or using a measuring instrument, and measures the white chromaticity.
In addition, the gradation reproduction characteristic measuring unit is configured to change the gradation value so that the brightness changes according to the type of the color monitor, and to change the gradation value so that the color changes. It is desirable to adjust the tone reproduction characteristics by performing a variation operation.

  In the first invention, the terminal device sets the chromaticity of the RGB primary colors according to the type of the color monitor to be connected, and measures the gradation reproduction characteristics of the RGB primary colors based on the display luminance and the gradation value of the color monitor. The white chromaticity of the color monitor is measured, and a monitor profile is created and held from data such as the chromaticity of the RGB primary colors, the gradation reproduction characteristics of the RGB primary colors, and the white chromaticity.

The “monitor profile” stores monitor profile data such as chromaticity of three primary colors RGB, which is a typical display characteristic of a color monitor, gradation reproduction characteristics, and white chromaticity. The color monitor has different display characteristics for each product, and when connected to a personal computer or the like, it is preferable to perform correction according to the individual display characteristics. In order to perform such correction, it is necessary to measure the display characteristics of individual monitors in advance and prepare the results as objective data. Usually, such data is called individual “monitor profile data”.
The “gradation reproduction characteristic” is a characteristic indicating the relationship between the input signal gradation value and the actual display luminance, and is generally called a gamma characteristic.
The “white chromaticity” is obtained as a gradation value of the three primary colors RGB necessary for causing each color monitor to perform white display.
“Measuring instruments” include non-contact and contact-type colorimeters that measure color patterns and white color instead of visual observation when measuring tone reproduction characteristics and white chromaticity.

The second invention is a program for causing a computer to function as the monitor profile creation system of the first invention.
A third invention is a recording medium on which a program for causing a computer to function as the monitor profile creating system of the first invention is recorded.

  The above-mentioned program may be held and distributed on a recording medium such as a CD-ROM, or the program can be transmitted and received via a communication line.

  The present invention can provide a monitor profile creation system that easily creates a monitor profile that performs high-accuracy correction according to the display characteristics of each monitor.

  Hereinafter, preferred embodiments of a monitor profile creation system and the like according to the present invention will be described in detail with reference to the accompanying drawings. In the following description and the accompanying drawings, the same reference numerals are given to components having substantially the same functional configuration, and redundant description will be omitted.

  FIG. 1 is a diagram showing a schematic configuration of a monitor profile creation system 100 according to the present embodiment of the present invention. As shown in FIG. 1, the monitor profile creation system 100 includes a monitor characteristic measurement device 101, a measuring instrument 105, and the like connected to a monitor 207 to be measured.

  The monitor characteristic measuring apparatus 101 is a personal computer or the like to which a monitor 207 having a function of displaying a color image to be measured is connected. The monitor characteristic measuring apparatus 101 measures characteristics such as gradation reproduction characteristics, chromaticity of three primary colors, and chromaticity of white, incorporates a program for creating a monitor profile in advance, and operates this program to A test pattern as will be described later is displayed on the screen of the monitor 207, and a response from the operator is obtained by using the input unit 205, so that data necessary for measurement is taken in, and these measurement results are monitored. Create and set a monitor profile as profile data.

  The monitor 207 to be a target for measuring profile data has a function of displaying a color image, and is not limited to a so-called CRT monitor, and includes a liquid crystal monitor, a notebook personal computer (PC) display, and the like. Note that “monitor” in this specification is synonymous with “display device”, and widely includes devices having a function of presenting an image based on an electrical signal. When connecting the monitor 207 and the monitor characteristic measuring apparatus 101, a graphic board that functions as an interface for transferring image signals is usually used. An image processing circuit such as this graphic board is used for the monitor 207. Since it is a component that influences the display characteristics, it constitutes a part of an object to be measured by the monitor characteristic measuring apparatus. In other words, the “monitor 207” in the present invention is a concept including an image processing circuit such as a graphic board.

The measuring device 105 is a color measuring device that can measure the color of a light-emitting object such as a monitor. When measuring gradation reproduction characteristics and white chromaticity, a color pattern or white color is measured instead of visual observation. There are non-contact type and contact type colorimeters. For example, as a typical model,
Examples include Spectrolino manufactured by GretagMacbeth.

  The monitor 207 and the monitor characteristic measuring apparatus 101 (personal computer) are connected by a VGA cable, a DVI cable, a BNC cable, etc. via a video card built in the monitor characteristic measuring apparatus 101 (personal computer). The measuring device 105 is connected to the monitor characteristic measuring apparatus 101 by serial, USB, IEEE 1394, or other methods. The monitor characteristic measuring apparatus 101 (personal computer) can control the measuring instrument 105 by sending a command to the measuring instrument 105 to obtain a colorimetric value.

  FIG. 36 is a diagram showing a schematic configuration of a monitor profile creation system 100 that visually measures gradation reproduction characteristics, white chromaticity, and the like. As shown in FIG. 36, the monitor profile creation system 100 that measures the gradation reproduction characteristics, white chromaticity, and the like by visual observation without using the measuring device 105 is a monitor characteristic measuring apparatus 101 to which a monitor 207 to be measured is connected. Etc.

  Next, the hardware configuration of the monitor characteristic measuring apparatus 101 will be described. FIG. 2 is a hardware configuration diagram of the monitor characteristic measuring apparatus 101.

  As shown in FIG. 2, the monitor characteristic measuring apparatus 101 includes a control unit 201, a storage device 202 (hard disk, external memory), a media input / output unit 203 (CD-ROM), a communication control unit 204 (communication control device, communication port, etc. ), An input unit 205 (keyboard, mouse, etc.), a printing unit 206 (printer), a monitor 207 (display), etc. are connected via a bus 209.

  The control unit 201 includes a CPU, a ROM, a RAM, and the like, and drives and controls each device connected via the bus 209 in accordance with a program stored in the storage device 202 as a large-capacity storage medium.

  In the storage device 202 (hard disk), a program for driving and controlling each component, an application program such as a program for measuring characteristics such as gradation reproduction characteristics, chromaticity of three primary colors, white chromaticity, and creating a monitor profile, Further, chromaticity data of RGB primary colors for each monitor type, a created monitor profile, and the like are stored.

  Each of these program codes is read by the control unit 201 as necessary, transferred to the RAM, read by the CPU, and executed as various means.

  The media input / output unit 203 (CD-ROM drive device) is used to upgrade the program and information stored in the ROM of the control unit 201 and the storage device 202, and make settings such as device settings.

  The communication control unit 204 is a communication control device, a communication port, and the like, and performs communication control.

The input unit 205 is a keyboard, a mouse, or the like, and inputs a response such as a match result for the test pattern displayed on the monitor 207, a monitor type, and the like.
As described above, the monitor 207 has a function of displaying a color image, and is a CRT monitor, a liquid crystal monitor, a notebook PC display, or the like, and displays an operation guide or a test pattern as described later on the monitor 207 screen. Then, by using the input unit 205 to obtain a response from the operator, data necessary for measurement is captured.
A printing unit 206 is a printer and performs print output processing.

  Next, a file layout related to the monitor profile creation system in the storage device 202 will be described. FIG. 3 shows a file arrangement related to the monitor profile creation system in the storage device 202. As shown in FIG. 3, the storage device 202 stores RGB primary color chromaticity data 301, a monitor profile 302, a control program 321, a monitor profile creation tool program 322, and the like.

The RGB primary color chromaticity data 301 stores combinations of chromaticities of a plurality of RGB primary colors for each monitor type. The chromaticity of the RGB primary colors for each monitor type is data obtained from the average value of various monitors for each monitor type.
The monitor profile 302 stores data such as chromaticity for each RGB primary color, tone curve indicating gradation reproduction characteristics for each RGB primary color, and white chromaticity.

The control program 321 is a program that drives and controls each component of the monitor characteristic measuring apparatus 101.
The monitor profile creation tool program 322 is an executable program for creating a monitor profile by measuring characteristics such as gradation reproduction characteristics, chromaticity of three primary colors, and chromaticity of white.

  Next, the process flow of the monitor profile creation system 100 will be described. 4 and 5 are flowcharts showing the processing procedure of the monitor profile creation system 100. FIG.

As shown in FIG. 4, the control unit 201 of the monitor characteristic measuring apparatus 101 displays a monitor type selection screen 601 on the monitor 207 (step S101).
FIG. 6 shows a monitor type selection screen 601. As shown in FIG. 6, the monitor type selection screen 601 includes a processing flow 610, a current processing unit 619, a monitor type 620, a forced end button 630, and the like. The process flow 610 includes monitor type selection 611, gradation adjustment 612, white adjustment 613, profile creation 614, profile setting 615, and the like, and the current processing unit 619 (“select monitor type” 611). ). Monitor types 620 include “CRT”, “liquid crystal monitor”, “notebook PC”, “other”, and the like.
The operator selects the type of monitor 207 (for example, “notebook PC”).

  The control unit 201 sets chromaticity data 301 of RGB primary colors for each monitor type from the storage device 202 according to the input monitor type 620 (step S102).

The control unit 201 displays the gradation adjustment screen 602 on the monitor 207 (step S103).
FIG. 7 shows a gradation adjustment screen 602. As shown in FIG. 7, the gradation adjustment screen 602 includes a processing flow 610, a current processing unit 619, a test pattern T1, a brightness type 622, a measurement stage status 623, a forced end button 630, a STOP button 631, and the like. .

  The processing flow 610 includes monitor type selection 611, gradation adjustment 612, white adjustment 613, profile creation 614, profile setting 615, etc., and the current processing unit 619 (“gradation adjustment” 612 ).

The test pattern T1 is a pattern composed of a first attribute region 50 and a second attribute region 60 arranged so as to be in contact with each other. The circular first attribute region 50 is a two-dimensional plane at a predetermined pitch. The background portion constitutes a second attribute region 60. A uniform pattern based on a combination of RGB gradation values having uniform brightness and color is displayed in the first attribute area 50, and a reference pattern having a predetermined reference luminance is displayed in the second attribute area 60. Is displayed.
The brightness type 622 represents the reference luminance of the reference pattern. For example, reference patterns “bright color”, “intermediate color”, “dark color”, and the like having three reference luminances are prepared. Reference brightness 75% is “bright color”, reference brightness 50% is “intermediate color”, and reference brightness 25% is “dark color”.

In the case of the present embodiment in which the gradation value changing operation for automatically performing the brightness changing operation and the color changing operation is executed, the brightness changing operation and the color changing operation are performed without waiting for the operation input from the operator. Execute.
As shown in the brightness type 622, the gradation value changing operation includes, for example, “bright color” with a reference luminance of 75%, “intermediate color” with a reference luminance of 50%, “dark color” with a reference luminance of 25%, and the like. For a reference pattern having a predetermined reference luminance, the brightness variation operation and the color variation operation of the uniform pattern are alternately executed while the variation amount is gradually reduced.

  An operator who views the test pattern T1 displayed on the screen of the monitor 207 in a state where the gradation value changing operation is performed, the brightness and color of the first attribute area 50 and the second attribute area 60 When both coincide with each other, the STOP button 631 is clicked. For example, 4 rounds (4 stages): “stage 1” rough brightness adjustment coincidence recognition, “stage 2” rough color coincidence recognition, “brightness” finer coincidence recognition than “stage 3”, “stage 4” The control unit 201 gradually increases the accuracy of adjustment and measures the gradation reproduction characteristics.

  The measurement stage status 623 indicates a measurement stage (for example, stage 3 (third round), etc.) of the current gradation reproduction characteristics according to the gradation value changing operation. When the monitor 207 is a liquid crystal monitor, additive color mixing does not hold. Therefore, the brightness change operation and the color change operation are alternately repeated, and the accuracy is gradually increased. For example, four-step measurement is performed. Therefore, the coincidence recognition by the color variation operation is not performed, and the coincidence recognition of only the brightness is gradually improved in accuracy (first coarse and then fine), and for example, two-step measurement is performed.

The control unit 201 performs a gradation reproduction characteristic measurement and adjustment process based on the input coincidence signal (step S104). In this embodiment, the gradation reproduction characteristic is measured by visual observation by an operator. An example of measurement using the measuring device 105 will be described later.
The control unit 201 uses the obtained tone curve indicating the tone reproduction characteristics of the RGB primary colors as monitor profile data (step S105).

  As for the method of measuring the gradation reproduction characteristics, which will be described later, in addition to the method of automatically changing the gradation value, an operation for changing the brightness and color by the operator using the operation panel displayed on the screen. A method of performing input and performing a gradation value changing operation, a test pattern, a basic configuration of the monitor characteristic measuring apparatus 101, and the like will be described in detail.

The control unit 201 displays a white adjustment screen 603 on the monitor 207 (step S106).
FIG. 7 shows a white adjustment screen 603. As shown in FIG. 7, the white adjustment screen 603 includes a processing flow 610, a current processing unit 619, a test pattern T2, a measurement stage status 623, a forced end button 630, a STOP button 631, and the like.

  The process flow 610 includes monitor type selection 611, gradation adjustment 612, white adjustment 613, profile creation 614, profile setting 615, etc., and the current processing unit 619 (“white adjustment” 613). Indicates.

  The test pattern T2 displays a test pattern having a square area in the illustrated example based on the combination of the gradation values of the three primary colors RGB. The size and shape of the displayed test pattern T2 are particularly It is not limited. A reference body RE showing white as a reference is prepared in advance, and adjustment is performed so that the color of the test pattern T2 displayed on the screen of the monitor 207 looks the same as the color of the reference body RE. The reference body RE is an actual object that is held by the operator's hand. The operator arranges the reference body RE in the vicinity of the test pattern T, and performs an operation of inputting the comparison result to the monitor characteristic measuring apparatus 101 while comparing both colors with the naked eye. The reference body RE may be any object as long as it is an object showing white as a reference. For example, a general card-like white paper, white tile, or the like can be used as the reference body RE.

The color of the test pattern T2 displayed on the screen of the monitor 207 also changes every moment by a changing operation that changes the gradation value with time according to a predetermined rule. The operator compares the color of the test pattern T2 that changes from time to time with the color of the reference body RE, and clicks the STOP button 631 when the two colors match. This operation is repeatedly executed (for example, performed in four stages) while gradually decreasing the variation amount and the variation range of the gradation value (the first is coarser and gradually becomes finer).
The measurement stage status 623 indicates the current white measurement stage (for example, stage 3 (third round)) according to the gradation value changing operation.

The control unit 201 performs white chromaticity measurement and adjustment processing based on the input coincidence signal (step S107). In the present embodiment, the reference white color is selected, and the reference white color is measured and visually measured by the operator. The white chromaticity is measured using the measuring device 105. Good.
The control unit 201 uses the color measurement value of the reference white as the white reference value as monitor profile data (step S108).
In addition, the measuring method of white chromaticity mentioned later is demonstrated in detail.

  In FIG. 4, the process is performed in the order of “tone adjustment” (steps S103 to S105) → “white adjustment” (steps S106 to S108), but the order may be reversed.

The control unit 201 generates a monitor profile 302 in the storage device 202 using data such as chromaticity of the three primary colors RGB, a tone curve indicating the gradation reproduction characteristics of the three primary colors RGB, and white chromaticity (step S109).
The control unit 201 displays a dialog (not shown) for specifying a storage destination, and stores the monitor profile 302 in the specified storage destination (step S110).

  The control unit 201 sets the monitor profile 302 by using the function or the like of the OS (for example, setting using a Web browser) (step S111).

  Next, the case where the tone reproduction characteristics are measured using the measuring device 105 (colorimeter) will be described in detail. FIG. 32 is a flowchart showing a processing procedure of the monitor profile creation system 100 using the measuring device 105. This processing describes an embodiment in which the measurement is performed using the measuring instrument of the gradation reproduction characteristic measuring means of claim 2.

  As shown in FIG. 32, the control unit 201 first sets the number of gradation reproduction characteristic measurement points N for measuring the gradation reproduction characteristic as the target value (step S201). In the case of a monitor that reproduces gradation with 256 gradations of 8 bits for each color, it is possible to accurately describe the gradation reproduction characteristics of the monitor 207 by measuring 256 points, but it takes time to measure all of them. Therefore, a general method is to measure less than 256 points and estimate the colorimetric values of points not measured by interpolation calculation. The number of measurement points is generally about 9 to 33 points.

The control unit 201 performs RGB primary color measurement (step S202) and white color measurement (step S203). The RGB primary colors are red (R): (RGB) = (255, 0, 0), green (G): (0, 255, 0), blue (B): (0, 0, 255) gradation values. Display color patches with and measure colors. For white, a color patch having a gradation value of (RGB) = (255, 255, 255) is displayed, colorimetric, and white chromaticity (x _w y _w ) is obtained. In FIG. 32, the colors are measured in the order of RGB primary color → white, but the order may be reversed.

The control unit 201 measures gradation reproduction characteristics. The control unit 201 initializes the number of measurement points i (i = 0) (step S204).
The control unit 201 displays and measures color patches of the same amount of RGB, and obtains chromaticity from the colorimetric values (step S206). As the chromaticity, an xy value of the Yxy color system, an a * b * value of the CIE LAB color system, or the like is used. The control unit 201 compares the chromaticity of white (x _w y _w ) with the chromaticity of the measurement color patch that is a colorimetric value (step S207), and if the difference is sufficiently small (Yes in step S207), The RGB values (R _i , G _i , B _i ) at that time are recorded, and if there is a difference (No in step S207), the increase / decrease in the RGB value (step 208) until the difference becomes sufficiently small. The colorimetry is repeated and the RGB values (R _i , G _i , B _i ) at that time are recorded.
The control unit 201 repeats this operation by the number of measurement points set as the target value (when the number of measurement points i <N) (step S205 to step 208).

FIG. 33 shows the measurement result of the gradation reproduction characteristic, and FIG. 34 is a graph of the gradation reproduction characteristic curve based on the result of FIG.
As shown in FIG. 33, for example, the measurement values of the gradation reproduction characteristics of the RGB primary colors with respect to 9 measurement points are shown. As shown in FIG. 34, from the result of FIG. 33, the gradation reproduction characteristic indicates that the gradation value (RGB value) of the input signal given to the monitor and the relative luminance (correction value) obtained on the monitor screen. The graph shows the relationship. Here, for convenience of explanation, it is assumed that the gradation value takes 256 steps from 0 to 255 expressed by 8-bit data, and the relative luminance is 0 to 1 (depending on the monitor capability or based on a predetermined setting). The minimum luminance to the maximum luminance). Among the three primary colors RGB, the red (R) and green (G) graphs have almost the same tone reproduction characteristics, while the blue (B) graph draws a slightly deviated curve. Therefore, different tone reproduction characteristics can be obtained.

  The control unit 201 performs a monitor profile creation calculation (step S209). For the RGB primary color and white chromaticity points described in the monitor profile 302, the measurement values in the previous step are used. The tone reproduction characteristics are obtained by interpolation calculation from the measurement results of the tone reproduction characteristics shown in FIG.

Next, a method for measuring gradation reproduction characteristics will be described in detail.
<<< §1. Conventional method for measuring gradation reproduction characteristics by visual observation >>>
First, the basic principle of a method for measuring the gradation reproduction characteristics of a monitor by visual observation that has been generally performed conventionally will be described. Normally, when measuring the monitor characteristics by visual observation, a program for measuring the gradation reproduction characteristics is previously installed in a personal computer connected to the monitor to be measured, and the monitor is operated by operating this program. Data required for measurement can be taken in by displaying a test pattern as described later on the screen and obtaining a response from the operator using an input device of a personal computer.

  It is possible to measure characteristics such as chromaticity of three primary colors, gradation reproduction characteristics, and white chromaticity using a personal computer, and these measurement results are generally called visually monitored profile data.

  FIG. 9 is a graph showing general tone reproduction characteristics of the monitor. As shown in the figure, this gradation reproduction characteristic is a graph showing the relationship between the gradation value of the input signal given to the monitor and the actual display brightness obtained on the monitor screen. Here, for convenience of explanation, it is assumed that the gradation value takes 256 steps from 0 to 255 expressed by 8-bit data, and the luminance is 0% to 100% (depending on the ability of the monitor or a predetermined setting). Based on the lowest luminance to the highest luminance).

  In this case, as shown in the graph of FIG. 9, the minimum gradation value 0 matches the minimum luminance 0% (the origin O of the graph), and the maximum gradation value 255 matches the maximum luminance 100% ( Graph point P). When data indicating the minimum gradation value 0 is input, display is performed with a minimum luminance of 0%. When data indicating the maximum gradation value 255 is input, display is performed with a maximum luminance of 100%. This is because the setting for performing the above is performed by a monitor circuit (usually a circuit on a graphic board). However, the relationship between the intermediate gradation value and the luminance is not necessarily a linear relationship. This is based on the characteristics of the D / A conversion circuit on the graphic board, and the gradation reproduction characteristics usually differ depending on the type of each monitor. Strictly speaking, it also depends on each lot. Different.

  In a general CRT monitor, it is known that a graph showing gradation reproduction characteristics can be approximated to a function curve having a term of γ power, “luminance = gradation value γ”. This γ value is set to “IEC 61966-2-1: Color Measurement and Management in Multimedia Systems and Equipment-Part2-1: Default RGB Color Space-2.2” in Windows (registered trademark). It is recommended. In addition, since Macintosh (registered trademark) has many uses for displaying printing data on a monitor, it is recommended to set the value to 1.8, which is close to the gradation reproduction characteristics of printing. The graph A indicated by the alternate long and short dash line in the figure shows the gradation reproduction characteristics in the case of γ = 2.2, but actually, for each individual monitor, as in the graphs B and C indicated by the solid line in the figure. A unique curve will be drawn. Therefore, when data indicating the gradation value 186 is given from the personal computer side to the monitor side, the monitor having ideal characteristics as shown in the graph A has a luminance of 50% that is the ordinate value of the point Q1. Although obtained, the monitors having the characteristics shown in the graphs B and C can obtain the luminance corresponding to the ordinate values of the points Q2 and Q3, respectively. In other words, the gradation value 186 corresponds to the abscissa value of the point Q4 in order to cause the monitor having the characteristics shown in the graph B to display the original luminance of 50% corresponding to the gradation value 186. In order to cause the monitor having the characteristic shown in the graph C to perform the process of correcting the gradation value 150, in order to display the original luminance of 50% corresponding to the gradation value 186, the gradation value 186 is changed. It is necessary to perform a process of correcting the gradation value 200 corresponding to the abscissa value of the point Q5.

  Such correction is generally called gamma correction. Eventually, when the monitor is connected to a personal computer or the like, a graph showing tone reproduction characteristics specific to the monitor is obtained in advance as monitor profile data, and gamma correction using this data is performed. There is a need.

  As already mentioned, there is a method using an optical measuring device as a method for measuring the gradation reproduction characteristics of each monitor. Usually, however, there is a method for obtaining characteristic data while visually observing with the human eye. Taken. FIG. 10 is a plan view showing the basic principle of a typical method for visually measuring the gradation reproduction characteristics. In this method, first, a test pattern as shown in FIG. 10A is displayed on the screen of a monitor to be measured. This test pattern is composed of a first attribute area 10 and a second attribute area 20. In the illustrated example, the first attribute area 10 is a square area, and the second attribute area 20 is a frame-shaped area surrounding the area. A uniform uniform pattern is displayed in the first attribute area 10, and a reference pattern having a predetermined reference luminance is displayed in the second attribute area 20.

  As described above, both ends of the graph of FIG. 9 are determined as points O and P regardless of the curve indicating the gamma characteristic. That is, the area given the data indicating the minimum gradation value 0 is always displayed with the lowest luminance 0% (black), and the area given the data indicating the maximum gradation value 255 is always the highest luminance 100% ( It is displayed in white. In the second attribute area 20, a reference pattern having a standard reference luminance is displayed using this property.

  FIG. 10B is a partially enlarged view of the second attribute area 20. As shown in the figure, in the second attribute area 20, a strip-shaped first sub-area 21 having a minimum gradation value 0 and a strip-shaped second sub-area 22 having a maximum gradation value 255 are alternately arranged. Consists of. In other words, a black and white stripe pattern is formed. Here, if the area ratio between the first sub-region 21 and the second sub-region 22 is set to 1: 1 (in other words, the widths of the black and white stripes are all set equal), Although the sub-regions 21 and 22 are displayed with a minimum luminance of 0% or a maximum luminance of 100%, if they are visually observed at a certain distance, they are recognized as regions that are displayed with a pseudo-luminance of 50%. It will be. Of course, for this purpose, it is necessary to set the width of the black and white stripe to be small to some extent so that it is difficult to visually observe the stripe pattern itself.

  Eventually, in the test pattern shown in FIG. 10A, the second attribute region 20 forming the surrounding frame region functions as a reference pattern that artificially shows 50% luminance. On the other hand, a uniform uniform pattern is displayed in the first attribute area 10 (in other words, all pixels have the same gradation value), but the brightness (gradation value) is determined by the operator. It is made variable by the input operation. Then, while allowing the operator to visually observe the test pattern, the brightness of the first attribute area 10 is the same as the brightness of the second attribute area 20 with respect to the pixels in the first attribute area 10. An operation for adjusting the gradation value is performed.

  Here, for example, if the brightness of the areas 10 and 20 is the same when the gradation value of the pixel in the area 10 of the first attribute is set to 85, the reference luminance is 50% in this monitor. It can be recognized that the gradation value corresponding to is 85. Therefore, as shown in the graph of FIG. 11, a point Q having a reference luminance of 50% and a corresponding gradation value 85 as both coordinate values is plotted, and a curve smoothly connecting the three points O, Q, and P can be obtained. For example, this curve is the tone reproduction characteristic (gamma characteristic) to be obtained. As described above, the tone reproduction characteristics of a general CRT monitor can be approximated by a function curve of “brightness = tone value γ”. Therefore, when three points are determined, a curve as shown in FIG. 11 is uniquely determined. It is possible. Eventually, when the monitor having the characteristics as shown in FIG. 11 is used to perform display corresponding to the luminance of 50%, data indicating the gradation value 85 may be given.

<<< §2. Measuring method of basic gradation reproduction characteristics according to the present invention >>>
According to the conventional method for measuring gradation reproduction characteristics described above, measurement based on visual observation by an operator is possible, and there is an advantage that a measurement result that matches the sensitivity characteristics of human eyes can be obtained. However, a color monitor or the like used for DTP processing for creating a printed material is required to measure gradation reproduction characteristics with higher accuracy, and a conventional measurement method cannot always obtain a sufficient measurement result. According to experiments conducted by the inventors of the present application, it has been confirmed that measurement with sufficient accuracy is difficult particularly for a liquid crystal color monitor and a CRT color monitor that has changed over time. The main reason for this is thought to be that in the case of a color monitor, the tone reproduction characteristics are different for each color.

  In general, in a color monitor, color images are displayed using the three primary colors RGB. Therefore, it is necessary to specify separate gradation values for each of the three primary colors RGB. However, the conventional method for measuring tone reproduction characteristics does not have the idea of measuring individual characteristics for each color, and only handles all three primary colors at once. For example, in the measurement using the test pattern as shown in FIG. 10A, the brightness adjustment in the first attribute region 10 is performed on the assumption that the gradation values of the three primary colors RGB are always common. For this reason, the tone reproduction characteristics obtained by the conventional method are characteristics common to the three primary colors RGB, and when the tone reproduction characteristics as shown in FIG. 11 are obtained, the same characteristics are used to obtain the three primary colors RGB. Gamma correction will be performed for all.

  Conventionally, such a handling has been performed because it has been considered that the gradation reproduction characteristics of the three primary colors RGB are almost the same in the case of a general color monitor. Certainly, in the case of a CRT color monitor, adjustments are made so that the tone reproduction characteristics of the primary colors RGB are substantially the same when the product is shipped. However, since the phosphors are deteriorated due to aging, the gradation reproduction characteristics for each primary color vary. In the case of a general liquid crystal color monitor, the gradation reproduction characteristics for each primary color are already different at the time of product shipment.

  The inventor of the present application measured the tone reproduction characteristics for each primary color using an optical measuring device for many types of CRT color monitors and liquid crystal monitors manufactured by many manufacturers. I found that there is a common tendency for many of the LCD monitors, whether they are new or used. Among the three primary colors RGB, the primary color R (red) and the primary color G (green) have almost the same gradation reproduction characteristics, whereas the primary color B (blue) has different gradation reproduction characteristics. It is a tendency to be. More specifically, for many liquid crystal color monitors, tone reproduction characteristics having a tendency as shown in FIG. 12 were obtained. In the illustrated example, graphs Cr, Cg, and Cb are gradation reproduction characteristics measured for primary colors R, G, and B, respectively. The graphs Cr and Cg depict the same curve, but the graph Cb depicts a curve that deviates slightly upward. On the other hand, in the case of a used CRT color monitor, on the contrary, only the graph Cb draws a curve slightly deviating downward.

  As for the reason why such a common tendency appears, theoretical analysis has not been made at present, but considering that almost the same trend was seen for any model of any manufacturer, It is considered that the color monitor using the three primary colors RGB is a universal tendency that is almost common. The inventor of the present application believes that such a tendency appears for the liquid crystal color monitor due to the properties of the liquid crystal material and the optical characteristics of the polarizing plate, and for the used CRT color monitor, the blue phosphor deteriorates. Is more severe than red and green phosphors. After all, as shown in FIG. 12, in order to cause a color monitor having different tone reproduction characteristics for each color to perform gray display with a luminance of 50%, for the primary colors R and G, the points Qr and Qg are changed. The abscissa value 85 is given as the gradation value, and for the primary color B, the abscissa value 46 of the point Qb needs to be given as the gradation value.

  The basic idea of the gradation reproduction characteristic measuring method of the present invention is based on the facts as described above, by obtaining all the gradation reproduction characteristics for each primary color of the three primary colors RGB independently, or at least the primary colors R, G By separately obtaining the tone reproduction characteristics for the primary color B and the tone reproduction characteristics for the primary color B, it is possible to measure the tone reproduction characteristics with high accuracy.

  The method for measuring gradation reproduction characteristics of a color monitor according to the present invention is a gradation reproduction showing a relationship between an input signal gradation value and an actual display luminance in a color monitor having a function of displaying a color image using three primary colors RGB. This is a device for visually measuring the characteristics, and its basic principle is to use a test pattern as shown in FIG. 10 (a), as in the conventional measuring method described in section 1. However, in the present invention, in order to obtain different gradation reproduction characteristics for each color, the following measures are taken.

  That is, in the first attribute region 10, a uniform pattern with uniform brightness and color is always displayed. The brightness and color of the uniform pattern are determined based on the operation of the operator, or It is made to change automatically based on a predetermined rule. The point that fluctuates not only the brightness but also the color is a new method not found in the conventional method. Then, the operator visually compares the first attribute area 10 and the second attribute area 20 until the operator recognizes that the brightness and color of both areas are the same. Continue the brightness and color variations for 10.

  In principle, the brightness variation and the color variation can be performed at the same time. However, in practice, the brightness variation operation and the color variation operation are performed separately. It is preferable that the brightness matching is recognized during the brightness changing operation and the color matching is recognized during the color changing operation.

  The brightness variation operation can be performed by increasing or decreasing the common variation amount for all the gradation values of the three primary colors RGB. For example, in a state where a predetermined uniform pattern is displayed in the first attribute area 10 with gradation values of R = 120, G = 120, and B = 120, an operation of increasing the common variation amount S = 5. If performed, the gradation values are R = 125, G = 125, and B = 125, and the luminance of the uniform pattern displayed in the first attribute area 10 slightly increases. Conversely, if the common variation S = 5 is reduced, the gradation values are R = 115, G = 115, and B = 115, and the luminance of the uniform pattern displayed in the first attribute area 10 Falls slightly. Such a brightness variation operation hardly changes the color by visual observation (although, of course, there is a possibility that the color variation is recognized strictly), and the operation mainly changes the brightness of the uniform pattern. It can be said.

  On the other hand, the color variation operation can be performed by an operation of increasing or decreasing the gradation value for any one specific color of the three primary colors RGB. For example, in a state where a predetermined uniform pattern is displayed in the first attribute area 10 with gradation values of R = 120, G = 120, and B = 120, the gradation value for the specific color R is changed by the variation amount. If the operation of increasing by S = 5 is performed, the gradation values are R = 125, G = 120, and B = 120, and the redness of the uniform pattern displayed in the first attribute area 10 may be slightly strengthened. it can. On the contrary, if the work of reducing the variation amount S = 5 is performed, the gradation values are R = 115, G = 120, B = 120, and the redness of the uniform pattern displayed in the area 10 of the first attribute is obtained. Can be slightly weakened. In such a color variation operation, there is little variation in brightness visually, and it can be said that the operation is mainly to change the color of a uniform pattern.

  In order to change the gradation value based on the operator's operation input, for example, an operation panel as shown in FIG. 13 is displayed on the screen, and the gradation value of each primary color is adjusted by the operator's mouse operation or the like. What should I do? In this operation panel, the brightness variation operation and the color variation operation can be performed separately and independently. That is, the four horizontal bars constituting this operation panel are all bars having a predetermined gradation value within a range of 0 to 255, and the position of the right end of the hatched bar is a predetermined floor. The key value is shown. The right end position of each bar is immediately corrected to the position clicked by the mouse cursor M, and the operator can set the right end positions of the four bars to arbitrary positions.

  Each bar marked with “RGB” in the figure is a bar for setting the gradation value of the primary color RGB. On the other hand, the bar marked “brightness” is always a bar indicating the average of the gradation values of the primary colors RGB at that time. Therefore, when the tone value is corrected (correction of the right end position) for any bar marked “RGB”, the tone value for the bar marked “Brightness” is also immediately linked and corrected. Is done. On the other hand, when the tone value for the bar marked “brightness” is corrected, the tone value for each bar marked “RGB” is immediately linked and corrected accordingly. (For example, the variation with respect to the “brightness” bar may be adjusted with a proration ratio according to the gradation value of each bar).

  If such an operation panel is used, the operator may perform a gradation value correction operation for a bar marked “brightness” or perform a color variation operation when performing a brightness variation operation. In this case, the gradation value correction operation may be performed for any bar marked “RGB”. For example, if you want to perform a fluctuation operation to make it brighter, you can click on the right position further than the right end of the bar marked `` brightness '', or if you want to perform a fluctuation operation that slightly reduces redness, What is necessary is just to click the mouse | mouth in the position slightly left of the right end of the bar described as "R".

  The operation panel shown in FIG. 13 is displayed in the vicinity of the test pattern shown in FIG. 10A, and the operator performs the brightness changing operation and the color changing operation, while the first attribute area 10 and the first pattern are displayed. If an adjustment is made so that the brightness and color of the two-attribute area 20 match, the tone reproduction characteristics for each primary color of the three primary colors RGB can be obtained separately and independently. For example, let us consider a case where the operator recognizes that both brightness and color match in a state where a reference pattern corresponding to 50% luminance is displayed in the second attribute area 20. As described above, when it is recognized that both the brightness and the color match, the operator clicks the match button 30. At this time, assuming that the gradation values indicated by the bars labeled “RGB” on the operation panel shown in FIG. 13 are R = 85, G = 85, and B = 46, respectively, the result is shown in FIG. Thus, the graphs Cr, Cg, and Cb showing the gradation reproduction characteristics for each primary color are obtained.

  However, the gradation value changing operation using the operation panel shown in FIG. 13 is practically difficult to implement unless it is a skilled operator. This is because a general operator can recognize that “the first attribute area 10 and the second attribute area 20 are slightly different in hue”, but “which color component of the three primary colors is increased or decreased. This is because it cannot be judged whether the same color can be obtained. As described above, when the measurement using the operation panel shown in FIG. 13 is performed, although independent and independent gradation reproduction characteristics can be obtained for all of the three primary colors RGB, in practice, the operator can perform measurement operations. This will impose a burden. The root cause is that four parameters of brightness, primary color R, primary color G, and primary color B are adjustment targets.

  Therefore, the present inventor has devised a practical operation panel as shown in FIG. The operation panel is provided with four adjustment buttons 31 to 34 and a coincidence button 30. The four adjustment buttons 31 to 34 are arranged when an XY two-dimensional coordinate system as shown in the figure is defined on the plane where each button is arranged (such a coordinate system is not displayed on an actual operation panel). The first button 31 and the second button 32 are arranged at opposing positions across the origin on the X axis, and the third button 33 and the fourth button 34 are arranged at opposing positions across the origin on the Y axis. It will be. The four adjustment buttons 31 to 34 are triangular in this example, but are not necessarily triangular.

  Here, the first button 31 is a button that gives an instruction to brighten the uniform pattern displayed in the area 10 of the first attribute, and the second button 32 is a button that gives an instruction to darken the uniform pattern, The third button 33 is a button that gives an instruction to strengthen the specific color component of the uniform pattern, and the fourth button 34 is a button that gives an instruction to weaken the specific color component of the uniform pattern. In this example, the primary color B is set as the specific color.

  The relationship between the operation of each button and the operation of changing the gradation value of each primary color is as follows. First, when there is an operation input to the first button (for example, a mouse click), a change operation for adding a common change amount is performed for all the gradation values of the three primary colors RGB, and an operation input to the second button is performed. If there is, a variation operation for reducing the common variation amount is performed for all the gradation values of the three primary colors RGB. In addition, when there is an operation input to the third button, a change operation for adding a predetermined change amount is performed on the gradation value of the specific color (primary color B in this example), and there is an operation input to the fourth button. In such a case, a variation operation is performed to reduce a predetermined variation amount for the gradation value of the specific color.

  For example, assuming that the variation amount S = 5 is set, every time the first button 31 is clicked, the correction is performed so that all the gradation values of the three primary colors RGB are increased by 5, and every time the second button 32 is clicked. Then, a correction is made so that all gradation values of the three primary colors RGB are reduced by 5. Similarly, every time the third button 33 is clicked, only the gradation value of the primary color B, which is a specific color, is increased by 5. Each time the fourth button 34 is clicked, the gradation value of the primary color B is corrected. Only a reduction of 5 is made. Of course, since the allowable range of each gradation value is 0 to 255, correction that exceeds the minimum gradation value 0 and the maximum gradation value 255 cannot be performed.

  Eventually, the adjustment objects on the operation panel shown in FIG. 14 are only two parameters, brightness and primary color B. In addition, since the brightness parameter adjustment is an operation related to the X-axis direction and the primary color B parameter adjustment is an operation related to the Y-axis direction, the operation system can be intuitively grasped. Compared with, the operability is greatly improved. The first button 31 and the second button 32 are buttons for performing a brightness changing operation that changes the gradation value so that the brightness of the uniform pattern changes mainly. The third button 33 and the fourth button 34 are This is a button for performing a color changing operation that changes the gradation value so that the color of the uniform pattern changes mainly.

  In addition, letters dark blue and yellow are shown beside the buttons 31 to 34, indicating intuitive guidelines for the operator. In other words, the operator clicks the first button 31 to make the correction brighter, clicks the second button 32 to make the correction darker, and makes it more bluish (to increase the blue component). If the third button 33 is clicked and the user wants to make it more yellowish (if the blue component is to be reduced), the fourth button 34 may be clicked. Finally, when it can be recognized that both brightness and color match, the match button 30 may be clicked.

  In the operation panel shown in FIG. 14, the gradation values of the three primary colors RGB cannot be set independently, and the gradation values of the primary color R and the primary color G are always the same. Accordingly, it is not possible to independently obtain all the gradation reproduction characteristics for each primary color of the three primary colors RGB. However, since the gradation value of the primary color B set as the specific color can be set to be different from the gradation values of the other primary colors R and G, the gradation reproduction characteristics for the primary colors R and G It is possible to obtain the tone reproduction characteristics for the primary color B independently.

  As already described with reference to the graph of FIG. 12, in many color monitors, for the primary color R and the primary color G out of the three primary colors RGB, substantially the same tone reproduction characteristics are obtained, whereas for the primary color B, There is a tendency that different gradation reproduction characteristics can be obtained. Therefore, assuming that the characteristics of the color monitor having such a tendency are measured, there is no practical problem if the gradation value is changed using the operation panel shown in FIG. In short, the operation panel shown in FIG. 14 uses a primary color B of the three primary colors RGB as a specific color, a graph showing gradation reproduction characteristics of the primary color B, and a graph showing gradation reproduction characteristics common to the primary colors R and G. , Can be determined separately.

  Note that the fluctuation amount S for increasing / decreasing the gradation value by clicking the button may be arbitrarily switched. For example, a rough adjustment setting with a fluctuation amount S = 5 and a fine adjustment setting with a fluctuation amount S = 1 are provided. In the first stage, rough gradation value changing operation is performed with the rough adjustment setting. When it is recognized that the brightness and the color are approximated to some extent, a method of switching to the fine adjustment setting and continuing the fine gradation value changing operation using the fine change amount can be adopted.

  Or it is also possible to make it the structure which changes the variation | change_quantity according to the click location of each button. For example, clicking on the tip of the triangle constituting each of the buttons 31 to 34 (the part away from the origin of the XY coordinate system) performs a gradation value variation operation with a large variation amount (for example, variation amount S = 5). If the base of the triangle (the part close to the origin of the XY coordinate system) is clicked, the operator can change the gradation value with a small amount of variation (for example, the amount of variation S = 1). As a result, an appropriate measurement operation can be performed by appropriately performing a click operation in accordance with the required fluctuation amount.

<<< §3. Method of automatically changing the gradation value >>>
In §2 described above, an example in which an operation input for changing the brightness and color is performed by the operator using the operation panel as shown in FIG. 13 or FIG. 14 and the gradation value is changed is shown. . In particular, if the operation panel shown in FIG. 14 is used, an adjustment operation corresponding to two parameters, which is bright or dark, bluish or yellowish, may be performed. Compared to the case where the operation panel shown in FIG. 13 is used. Thus, the operator's workload is greatly reduced. However, no matter which operation panel is used, there is no change in that the operator himself / herself has to perform an operation input in the direction in which the brightness and color match.

  Here, a method for further reducing the burden of such operation input will be described. The main point of this method is to automatically change the gradation value of the uniform pattern displayed in the region 10 of the first attribute with time according to a predetermined rule set in advance. When it is recognized that the brightness and color match the reference pattern, the user is notified by clicking the match button. Here, as a rule for automatically changing the gradation value with time, any rule may be used as long as the brightness and the color change within a necessary range. Practically, it is preferable to adopt a rule that executes two kinds of changing operations, that is, an operation for changing the brightness and an operation for changing the color.

  Specifically, for each of the gradation values of the three primary colors RGB, a brightness fluctuation operation for changing the gradation value mainly so that the brightness of the uniform pattern changes by adding or subtracting a fluctuation amount common to a predetermined timing. A predetermined variation amount is added or reduced at a predetermined timing with respect to the gradation value of any one of the three primary colors RGB (practically, the primary color B is preferably a specific color as described above). Thus, it is only necessary to perform two kinds of changing operations, ie, a color changing operation for changing the gradation value so that the color of the uniform pattern changes.

  The brightness fluctuation operation described above corresponds to a process of automatically clicking the first button 31 or the second button 32 on the operation panel shown in FIG. 14 at a predetermined timing. For example, if a common variation amount S = + 5 (+ indicates that the gradation value is increased) is set and a repetition cycle is set every second as a predetermined timing, each gradation value of the three primary colors RGB is set. Everything will automatically increase by 5 every second. Alternatively, if the common variation amount S = −6 (− indicates that the gradation value is decreased) and the repetition cycle is set every 2 seconds as the predetermined timing, each gradation value of the three primary colors RGB is set. Will automatically decrease by 6 every 2 seconds.

  Since each gradation value can only have an allowable range of 0 to 255, when the gradation value obtained by the variation operation for adding the variation amount exceeds the maximum gradation value 255, the excess is minimized. When the gradation value obtained by the fluctuation operation for subtracting the fluctuation amount is performed from the gradation value 0 and the gradation value obtained by the fluctuation operation falls below the minimum gradation value 0, the excess is counted from the maximum gradation value 255. Make a circular process. For example, when the fluctuation amount 5 is added to the gradation value 253, the gradation value becomes 258. In this case, the gradation value 2 obtained by subtracting 256 is used instead. In short, the gradation values are circulated in the order of 255 → 0, and the excess gradation values for three stages are counted from the minimum gradation value 0 to 0, 1, 2, and so on. Similarly, when the fluctuation amount 6 is subtracted from the gradation value 2, the subtraction result is −4, but the gradation value 252 obtained by adding 256 is used instead. In short, the gradation values are circulated in the order of 0 → 255, and the excess gradation values for four stages are counted from the maximum gradation values 255 to 255, 254, 253, 252.

  The gradation initial value of each primary color in such a brightness variation operation may be arbitrarily set. However, in practice, the gradation initial value of the three primary colors may be set to a predetermined common value. For example, if R = 0, G = 0, and B = 0 are set as initial values and are varied by a common variation amount S = + 5, the gradation values of the primary colors are 0 → 5 → 10 → 15 →. ... → 250 → 255 → 4 → 9 → 14 →... When such a change operation is automatically performed, when viewed from the operator, the uniform pattern in the first attribute area 10 is sometimes black, dark gray, intermediate gray, light gray, white, black, and so on. The state of changing every moment will be observed. Since the reference pattern having a luminance of 50% is displayed in the second attribute area 20, the operator recognizes that the brightness of the reference pattern matches that of the uniform pattern when it becomes intermediate gray. It will be. When the operator recognizes that the brightness matches, the operator inputs input indicating brightness match (for example, clicks on the brightness match button).

  Of course, since this is an operation performed by a human, the determination of coincidence recognition may be delayed and the timing for performing the coincidence input operation may be lost. In that case, the uniform pattern passes through the intermediate gray and transitions to a light gray, but after a while, it will circulate to a black state again, Opportunities to perform a match input operation come around again. In this way, by adopting a method in which the gradation value is repeatedly circulated and changed, it is possible to give the operator a chance to perform the coincidence input operation many times, so that more accurate coincidence input can be expected. In fact, if it is circulated several times, the operator can grasp the period of gradation change sensuously, and finally an accurate coincidence input operation becomes possible.

  Note that if the variation amount S is set to be large to some extent, it may not be possible to recognize that it is completely matched from the operator's eyes. In such a case, an input indicating coincidence recognition may be performed when the distance is closest. This applies not only to brightness matching recognition but also to color matching recognition described later. In short, in the present invention, “coincidence recognition” by the operator does not necessarily mean that the operator has completely matched, but also includes a recognition range in which brightness and color can be determined to be closest under a predetermined condition. It is a waste. Actually, when the contour of the first attribute area 10 is buried in the second attribute area 20 and it looks as if it has melted, the recognition of matching is performed.

  While the brightness variation operation has been described above, the color variation operation is almost the same. The color variation operation corresponds to a process of automatically clicking the third button 33 or the fourth button 34 on the operation panel shown in FIG. 14 at a predetermined timing. For example, if a common variation S = + 5 is set and a repetition cycle is set every second as a predetermined timing, only the gradation values of specific colors of the three primary colors RGB are set to 5 per second. It will increase automatically. When the primary color B is a specific color, the tint of the uniform pattern gradually increases blueness. Of course, in this color variation operation as well, since the circular processing is performed so that the gradation value is within the allowable range of 0 to 255, immediately after the blueness reaches the maximum, the yellowness is maximum (the blueness is minimum). ) State. The gradation values of the primary colors R and G remain constant.

  As described above, when the color variation operation is automatically performed, when viewed from the operator, the uniform pattern in the region 10 of the first attribute gradually fades away from a strong yellowish color to an achromatic color. After becoming a close color, the blue color gradually increases, and after the blue color reaches the maximum, it is observed that the color returns to a strong yellow color again. Since an achromatic reference pattern having a luminance of 50% is displayed in the second attribute area 20, the operator can change the reference pattern when the very light color of the uniform pattern changes from yellow to blue. You will get the recognition that it matches the color. When the operator recognizes that the colors match, he / she inputs the color match (for example, clicks on the color match button).

  This determination of color matching is also a very delicate sensory determination for the operator, and the timing for performing the matching input operation may be missed. However, as with the brightness transition, the color transition is repeated in a circular fashion, so there will be many chances to perform a match input operation. It becomes possible.

  FIG. 15 is a diagram illustrating an example in which an operator performs brightness matching input operation and color matching input operation on the operator while automatically executing brightness variation operation and color variation operation based on a predetermined rule based on the above-described principle. It is a figure which shows an example of the operation panel used in order to perform. As shown in the figure, there are three types of buttons operated by the operator: a start button 40, a brightness match button 41, and a color match button 42, and an explanatory note for the operation is attached to the side of each button. . When the operation panel as shown in FIG. 15 is displayed in the vicinity of the test pattern shown in FIG. 10A and the operator clicks each button using a mouse or the like, a series of measurement operations is completed. It will be.

  First, the operator clicks the start button 40 in accordance with the explanatory text written as step 0. As a result, the automatic brightness variation operation described above is executed, and the brightness of the uniform pattern in the region 10 having the first attribute starts to vary from moment to moment. Therefore, the operator clicks the brightness matching button 41 when he feels that the brightness of the uniform pattern is the same as the brightness of the reference pattern according to the explanatory text written as step 1. As a result, the automatic color change operation described above is executed this time, and the color of the uniform pattern (the color related to the primary color B) starts to change every moment. Therefore, the operator clicks the color matching button 42 when he / she feels that the color of the uniform pattern is the same as the color of the reference pattern according to the explanatory text written as step 2.

  This completes a series of measurement operations. The gradation values of the three primary colors RGB at the time when the color matching button 42 is clicked (in this example, R and G have the same value) are used as the corresponding gradation values for each primary color corresponding to the reference luminance of 50%. A point corresponding to the point Q in FIG. 11 is plotted, and a graph of gradation reproduction characteristics for each primary color (R and G are the same graph) may be obtained.

  After all, the brightness match button 41 shown in FIG. 15 is a brightness match signal input for inputting a brightness match signal indicating that the brightness is matched from the operator in a state where the brightness variation operation is being performed. The color matching button 42 functions as a color matching signal input unit for inputting a color matching signal indicating that the color has been matched from the operator in a state where the color variation operation is being performed. Will do. When the input of both the brightness match signal and the color match signal is completed, it is treated as if the match signal indicating that the brightness and the color match is input, and the gradation for each primary color Reproducibility characteristics are required. In the above example, the primary color B of the three primary colors RGB is a specific color, and a graph showing the gradation reproduction characteristics of the primary color B and a graph showing the gradation reproduction characteristics common to the primary colors R and G are obtained separately. It is done.

  In the example using the operation panel shown in FIG. 15, the measurement operation is completed by performing the brightness matching signal input operation and the color matching signal input operation once each. It is preferable to adopt a form in which these operations are alternately executed repeatedly. The first reason is that this coincidence recognition operation is a human visual sensory operation, and thus accurate recognition cannot always be performed by a single input operation. The second reason is that the brightness changing operation does not necessarily change only the brightness, and the color changing operation does not necessarily change only the color. For example, even if the brightness matches exactly when the brightness matching button 41 is clicked on the operation panel of FIG. 15, the color variation operation to be executed subsequently makes the brightness not only the color. As a result, the brightness consistency is lost. In order to avoid such adverse effects, it is effective to repeatedly perform operations that match the brightness and operations that match the colors, especially repeatedly while gradually reducing the amount of variation in the gradation value. It is effective to do.

  Specifically, the process shown in FIG. 16 may be performed. First, in step S1, an initial value of each gradation value of the three primary colors R, G, and B and an initial value of the variation amount S are set. In the illustrated example, R0, G0, B0, and S0 are set.

  Subsequently, in steps S2 and S3, an operation for matching the brightness is executed. That is, first, in step S2, a process of adding the variation amount S to the gradation values of the three primary colors R, G, and B is performed. However, since the above-described circulation processing is performed, 256 is subtracted when the gradation value exceeds 255. In step S3, it is determined whether or not the brightness matching button has been pressed. If not, the process returns to step S2 to update the gradation value. Thus, the processes in steps S2 and S3 are repeated until the brightness matching button is pressed. As a matter of course, the cycle of this repetitive process is set to a time sufficient for the operator to make a determination of coincidence recognition, for example, every second.

  If it is detected in step S3 that the brightness matching button has been pressed, then in steps S4 and S5, an operation for matching the colors is executed. That is, first, in step S4, a process of adding the variation amount S only to the gradation value of the specific color B is performed. Since the circulation process is performed here, 256 is subtracted when the gradation value exceeds 255. In step S5, it is determined whether or not a color matching button (which may also be used as a brightness matching button) has been pressed. If not, the process returns to step S4 to return to the floor for the specific color B. Updates the key value. Thus, the processes in steps S4 and S5 are repeated until the color matching button is pressed. As for the cycle of this repetitive process, for example, every second, a time sufficient for the operator to make a match recognition determination is set.

  If it is detected in step S5 that the color match button has been pressed, both the brightness match signal and the color match signal are input from the operator, but at this point, the measurement result is still obtained. The determination of the gradation value is not performed, and the procedure from step S2 is executed again from step S6 to step S7. Moreover, in step S7, an update process for reducing the fluctuation amount S is performed. Therefore, the fluctuation amount S added in steps S2 and S4 in the second round is smaller than the value in the first round, and finer matching determination is possible. If necessary, the variation S is further reduced and the third and fourth rounds are repeated.

  For example, if the initial value S0 of the fluctuation amount S is set to +5, and updating is performed to decrease this by two in step S7, and the default value of the fluctuation amount S in step S6 is set to 1, one cycle is performed. The variation amount S = + 5 for the second, the variation amount S = + 3 for the second round, and the variation amount S = + 1 for the third round. The repetition process is completed after three rounds. In this way, when the fluctuation amount S reaches a predetermined specified value set in advance, the process proceeds from step S6 to step S8, and the gradation values of the three primary colors R, G, and B at that time are output. As described above, the gradation reproduction characteristics for each primary color are obtained using these gradation values as the corresponding gradation values corresponding to the reference luminance of 50%.

  In the procedure shown in FIG. 16, there is a great difference in recognition conditions between the first round of coincidence recognition and the second round of coincidence recognition. For example, the coincidence recognition in step S3 in the first round indicates that the brightness has reached a certain degree of coincidence, but color coincidence is not considered at that time. However, since the coincidence recognition in step S3 of the second round is already the coincidence recognition of brightness on the assumption that the color coincidence recognition has been completed in step S5 of the first round, Considering the original purpose of matching both of these, a more preferable matching state is obtained. In addition, since the amount of variation S is reduced every time a round is made so that fine match recognition is performed, in the match recognition in step S3 of the third round, the match recognition in step S3 of the second round is performed. A more preferable coincidence state is obtained.

  After all, the procedure shown in FIG. 16 starts the color variation operation (step S4) when the brightness coincidence signal is input (step S3) when the brightness variation operation is performed (step S2). When the color matching signal is input in the state where the changing operation is performed (step S4) (step S5), the brightness changing operation (step S2) is started, and the brightness changing operation and the color changing operation are repeatedly executed alternately. In addition, it can be said that the gradation value variation S is gradually reduced (step S7). When the input of both the brightness match signal and the color match signal is completed after the fluctuation amount S reaches a predetermined specified value, a match signal indicating recognition that both the brightness and the color match is obtained. It will be treated as input.

  As the variation amount S, a negative value can be set. In that case, in steps S2 and S4, the gradation value after the change is substantially obtained by subtraction, and when the gradation value after the change becomes a negative value, a process of adding 256 is performed. . Of course, in step S7, updating is performed so that the absolute value of the fluctuation amount S gradually decreases.

  In the above-described embodiment, the gradation value is repeatedly changed by a circular motion of 0-255 → 0-255 → 0-255..., But the gradation value is repeatedly changed by a reciprocating motion. You may do it. In this case, when a variation value exceeding the maximum gradation value or the minimum gradation value is obtained, a folding process is performed and the sign of the variation amount S is reversed. Specifically, when the gradation value is gradually increased by the positive fluctuation amount + S and the maximum gradation value 255 is exceeded, the sign of the fluctuation amount is reversed and the negative fluctuation amount is obtained. The gradation value is gradually decreased by -S, and as a result, when the minimum gradation value 0 is exceeded, the sign of the variation amount is reversed, and the gradation is gradually increased by the positive variation amount + S again. Just increase the value. As a result, the process of gradually increasing the gradation value from 0 to 255 and the process of gradually decreasing the gradation value from 255 to 0 are alternately performed.

  Furthermore, in the above-described example, whether the gradation value is repeatedly changed by a circular motion or a reciprocating motion, the gradation value is changed over the entire range of 0 to 255 which is an allowable range of the gradation value. The above need not necessarily vary over this entire range. For example, if the tone reproduction characteristics of the monitor to be measured is a graph as shown in FIG. 12, the tone values of R = 85, G = 85, and B = 46 are finally referred to. The corresponding gradation value corresponding to the luminance of 50% is obtained. These values are considerably biased toward the 0 side as compared with the median value 128 in the range of 0 to 255. However, in a general monitor, it is practically unlikely that a value of 10 or 20 or a value of 240 or 250 is obtained as a corresponding gradation value corresponding to a reference luminance of 50%. Therefore, practically, for example, the circulation motion or the reciprocation motion may be performed within a limited range of 30 to 230.

  Further, when the process is repeatedly performed while gradually reducing the fluctuation amount S as in the procedure shown in FIG. 16, the gradation value for performing the circulation motion and the reciprocating motion at the same time as reducing the fluctuation amount S. If the fluctuation range is narrowed, more efficient measurement work becomes possible. For example, in steps S2 and S4 in the first round in which the variation amount S = + 5, the gradation value variation range is set to the entire allowable range of 0 to 255. Then, in steps S2 and S4 in the second round in which the fluctuation amount S = + 3, the gradation value fluctuation range is narrowed, for example, within a range of ± 30 centering on the gradation value before the fluctuation. deep.

  Then, for example, when the results of R = 90, G = 90, and B = 50 are obtained at the time when the first round is completed, in steps S2 of the second round, R = 60 to 120, G = Variation within a limited range of 60 to 120, B = 20 to 80 is performed. Rough values for the gradation values of the primary colors that are expected to be matched in brightness and color already in the first round of processing (in this example, R = 90, G = 90, B = 50) ) Is obtained, it can be said that in the second round, it is sufficient to vary within a range of ± 30 around this rough value. It is inefficient to change to a gradation value that has no possibility. Similarly, in the third round, for example, the variation amount S may be set to +1 and the gradation value before the variation may be set within a range of ± 10 around the center.

<<< §4. How to plot more points >>
In order to obtain the gradation reproduction characteristics as shown in the graph of FIG. 11, points Q other than the end points O and P of the graph are plotted, and an approximate function curve passing through the three points O, P and Q is obtained by calculation. The good thing is as already mentioned in §1. Then, in order to obtain the position of the point Q by visual measurement, a test pattern as shown in FIG. 10A is used, and a black and white stripe as shown in FIG. As described above, a reference pattern composed of a pattern having a reference luminance of 50% is displayed and the identity with the uniform pattern in the first attribute region 10 is visually confirmed.

  As described above, the gradation reproduction characteristic (gamma characteristic) can be obtained as an approximate function curve passing through three points O, P, and Q. The gradation reproduction characteristic of a general CRT monitor is “brightness = scale”. This is because it is known that the function curve has a term of γ power called “tone value γ”. This is because a relationship “L = Eγ” is obtained between the voltage E applied to the cathode ray tube and the light emission output L in the first place. Therefore, in the case of a monitor using a cathode ray tube, it is sufficient if the corresponding gradation value is measured using the reference pattern corresponding to the reference luminance of 50% and the point Q can be plotted. However, in a liquid crystal monitor or the like, the gradation reproduction characteristics are not always a function curve having a γ power term.

  When the gradation reproduction characteristic graph cannot be approximated by a function curve having a γ-th term, it is difficult to obtain an accurate approximate function curve by calculation using only three points O, P, and Q. Therefore, here, an example will be described in which a tone reproduction characteristic represented by an arbitrary function is obtained by plotting a larger number of points on a graph. Specifically, as shown in FIG. 17, in addition to the two end points O and P of the graph, three points Q1, Q2, and Q3 are plotted, and an approximate function curve that passes through the five points O, Q1, Q2, Q3, and P. An embodiment in which is obtained by calculation will be described.

  First, the point Q2 shown in FIG. 17 can be measured by the method described so far. That is, the point Q2 shown in the figure can be plotted based on the measurement result that the corresponding gradation value for the reference luminance of 50% is 85. As shown in FIG. 10B, such a measurement is performed by using a test pattern in which a reference pattern having a pseudo luminance of 50% is displayed in the second attribute area 20, and the first attribute area. 10 is performed by a gradation value variation process for matching the brightness and color of the uniform pattern displayed in 10.

  On the other hand, in order to obtain the points Q1 and Q3 shown in FIG. 17, the reference brightness of the reference pattern displayed in the second attribute area 20 is changed to 25% and 75%, respectively, and the measurement process according to exactly the same procedure is performed. Just do it. In the example shown in FIG. 17, the point Q1 is plotted based on the measurement result that the corresponding gradation value is 26 for the reference luminance of 25%, and the point Q3 is determined based on the measurement result that the corresponding gradation value is 148 for the reference luminance of 75%. This is a plotted example. Of course, actually, the corresponding gradation values corresponding to the reference luminances of 25%, 50%, and 75% are obtained for each primary color, and the plots of the points Q1, Q2, and Q3 are also performed for each primary color. It will be.

  The reference luminance of the reference pattern can be arbitrarily set by adjusting the area ratio between the first subregion 21 and the second subregion 22. For example, in the case of the reference pattern shown in FIG. 10B, the strip-shaped first subregions 21 having the minimum gradation value 0 and the strip-shaped second subregions 22 having the maximum gradation value 255 are alternately arranged. Since the area ratio between the first sub-region 21 and the second sub-region 22 is set to 1: 1, the reference luminance is 50%. If this area ratio is set to 3: 1 (for example, if the width of the black band is set to three times the width of the white band), a reference pattern with a reference luminance of 25% can be realized. If it is set to 1: 3 (for example, if the width of the black band is set to 1/3 times the width of the white band), a reference pattern with a reference luminance of 75% can be realized.

  In general, by setting a plurality of N area ratios between the first sub-region 21 and the second sub-region 22, it is possible to generate N reference patterns having different reference luminances. Then, as described above, if the N test patterns using the N reference patterns are subjected to a visual measurement operation by the operator, N corresponding gradation values corresponding to each reference luminance can be obtained. Therefore, as shown in FIG. 17, a two-dimensional coordinate system is defined in which the gradation value is taken on the first coordinate axis (horizontal axis) and the luminance is taken on the second coordinate axis (vertical axis). Plot N points (three points Q1, Q2, Q3 in the example of FIG. 10) having the reference luminance and the corresponding gradation value as coordinate values, and further coordinate the minimum luminance value and the minimum gradation value. A point having a value (origin point O in the case of FIG. 17) and a point having the maximum luminance value and the maximum gradation value as coordinate values (point P in the case of FIG. 17) are plotted, and the plotted total What is necessary is just to obtain | require the graph which shows the gradation reproduction characteristic for each primary color by making into a graph which shows a gradation reproduction characteristic the graph which passes (N + 2) point.

  As described above, various methods are known for obtaining an approximate function curve passing through a plurality of coordinate points plotted on a two-dimensional coordinate system. For example, spline curves and Bezier curves are widely known as approximate function curves that pass through a plurality of points. Therefore, if necessary, approximation using these curves may be performed.

  As described above, in the case of a general CRT monitor, five points O, Q1, Q2, Q3, and P as shown in FIG. 17 are plotted, and approximation by a function curve defined in the form of a power is possible. It is. However, according to the measurement by the inventors of the present application, an S-shaped characteristic curve as shown in FIG. 18 is often obtained with a liquid crystal monitor or the like. Such an S-shaped characteristic curve cannot be approximated by a general gamma characteristic curve defined in the form of a power, so that approximation using a spline curve, a Bezier curve, or the like can be performed.

  However, in practice, approximation using a spline curve or a Bezier curve is not always appropriate. The reason is that spline curves and Bezier curves are curves for expressing the contour shape of an object used in so-called drawing format drawing software, which is inconvenient for expressing a graph having physical meaning. This is because there are points. More specifically, the gradation value and the luminance, which are both variables of the function indicating the gradation reproduction characteristics, are variables that should take positive values and do not show negative values. Therefore, the graph shown in FIG. 18 is also a graph defined only in the first quadrant of the two-dimensional coordinate system. However, when approximation using a spline curve, Bezier curve, etc. is performed, such an approximation that ignores the physical meaning is performed, resulting in the graph protruding into the second and fourth quadrants. It might be. Therefore, when calculating an approximate curve, some consideration is required.

  Therefore, the present inventor first tried to approximate the five points O, Q1, Q2, Q3, and P plotted on the two-dimensional coordinate system using a function curve defined in the form of a power, and the approximation was not successful. In this case, it is considered that this is an S-shaped characteristic curve as shown in FIG. 18, and is divided into two parts by the following method, and each part is a function curve defined in the form of a power. It has been found that it is effective to use an approximation method. Specifically, in the case of the example shown in FIG. 18, a first function curve that passes through the points O, Q1, and Q2 and a second function curve that passes through the points Q2, Q3, and P What is necessary is just to approximate by two function curves. Here, the two function curves may be approximated by function curves defined in the form of a power. By doing so, a graph in the first quadrant is surely obtained.

  Eventually, this technique is such that when the five points plotted on the two-dimensional coordinate system are called the first to fifth points in ascending order of the coordinate values on the first coordinate axis, the first and second points are called. , A first function curve in which the brightness is defined in the form of a power of a gradation value through each third point, and a form in which the brightness is a power of a gradation value through each of the third, fourth, and fifth points The second function curve defined in (2) is obtained by calculation, and a curve formed by connecting the first function curve and the second function curve is referred to as a technique for making a graph showing the gradation reproduction characteristics. it can. In this way, when two function curves are connected, the curvatures of both function curves may deviate at the third point (point Q2 in FIG. 18), which is the connection point, but exhibits tone reproduction characteristics. There is no particular problem in using the graph.

<<< §5. More preferred test pattern >>
Next, a more preferable test pattern T1 will be described in practicing the present invention. In the embodiment described so far, as shown in FIG. 10A, the first attribute area 10 having a square shape and the second attribute area 20 having a frame shape surrounding the periphery thereof are configured. As shown in FIG. 10B, a striped reference pattern is formed in the second attribute region 20 using the test pattern T1. Such a test pattern T1 is a pattern conventionally used, but is not necessarily an optimal test pattern.

  The inventor of the present application uses a test pattern T1 as shown in FIG. 19A rather than the conventional test pattern shown in FIG. 10A and uses the test pattern T1 as shown in FIG. It has been found that more accurate measurement is possible by using a reference pattern as shown in (b). The test pattern T1 shown in FIG. 19A is composed of a first attribute area 50 for displaying a uniform pattern and a second attribute area 60 for displaying a reference pattern. As shown in the enlarged plan view of FIG. 19B, the first sub-region 61 (black cell in the figure) and the second sub-region 62 (white cell in the figure) form a checkered pattern. In FIG. 19A, for convenience of illustration, the second attribute area 60 is hatched with a horizontal line. However, in actuality, the second attribute area 60 is shown in FIG. A reference pattern having a reference luminance of 50%, which is a checkered pattern as shown in the enlarged plan view of FIG. The characteristics of the test pattern T1 shown in FIG. 19A and the reference pattern shown in FIG. 19B and the inherent effects obtained by the characteristics will be described below.

(1) Features related to the reference pattern When comparing the reference pattern shown in FIG. 19B with the reference pattern shown in FIG. 10B, the latter is composed of a black and white stripe pattern, whereas the former is It can be seen that it is composed of black and white checkered patterns. Here, the reference pattern shown in FIG. 19B is a checkered pattern because it happens that this reference pattern is a pattern showing a reference luminance of 50%, and the essence is the first sub-region. 61 (black) and the second sub-region 62 (white) are configured by unit cells having the same shape and size, and a reference pattern is configured by a two-dimensional arrangement of the unit cells. In particular, in the example shown here, the reference pattern is configured by arranging rectangular unit cells (square in this example) in a two-dimensional matrix.

  As described above, the reference pattern configured by the two-dimensional arrangement of unit cells having the same shape and size has the effect of further improving the pseudo-uniformity at the time of observation as compared with the reference pattern made of a stripe pattern. Have. At the time of visual measurement by the operator, the reference pattern is observed from a certain viewing distance. Therefore, in actuality, both the stripe pattern and the checkered pattern are directly recognized by the operator. None of them are recognized as a substantially gray uniform pattern. However, since the checkered pattern is composed of finer unit cells, the uniformity during observation is further improved.

  This feature is particularly noticeable when a reference pattern having a reference luminance other than 50% is formed. For example, in the embodiment described in §4, it is necessary to prepare reference patterns having three reference luminances of 25%, 50%, and 75%. In such a case, a two-dimensional array of unit cells is used. The method of forming the reference pattern is particularly effective. FIGS. 20A and 20B show an example in which a reference pattern having a reference luminance of 25% and 75% is formed using a reference pattern in which rectangular unit cells are arranged in a two-dimensional matrix. In FIG. 20B, for convenience of explanation, the boundary lines of the unit cells constituting the second sub-region 62 (white) are shown. In practice, however, the boundary lines between the white cells are Do not show.

  The reference luminance is set by changing the area ratio between the first subregion 61 (black) and the second subregion 62 (white). That is, in order to set the reference luminance to 25%, the area ratio needs to be 3: 1, and in order to set the reference luminance to 75%, the area ratio needs to be 1: 3. When a reference pattern in which rectangular unit cells are arranged in a two-dimensional matrix is used, an area ratio of 1: 1 (FIG. 19B), 3: 1 (FIG. 20A), 1: 3 (FIG. The setting of b)) can be performed rationally, and a pattern with sufficiently ensured pseudo uniformity can be obtained.

  In each of these three reference patterns, one cell group is composed of four unit cells arranged in two rows and two columns. Here, among the four unit cells constituting each cell group, the first sub-region 61 (black) is constituted by a pair of unit cells diagonally adjacent to each other, and the second sub-region is constituted by the remaining pair of unit cells. If 62 (white) is configured, the reference pattern shown in FIG. 19B having an area ratio of 1: 1 can be configured. Of the four unit cells constituting each cell group, one unit cell constitutes one sub-region, and the remaining three unit cells constitute the other sub-region, with an area ratio of 3: 1 or 1 If the reference pattern of 3: 3 is configured, the reference pattern shown in FIG. 20A or 20B can be configured. In any case, the formed reference pattern is a repetitive pattern of a cell group composed of four unit cells arranged in 2 rows and 2 columns, so that sufficient pseudo uniformity can be ensured.

  In short, for any odd number i, j, the unit cell in the i-th row and j-th column, the unit cell in the i-th row (j + 1) column, the unit cell in the (i + 1) -th row and j-th column, the (i + 1) -th row (j + 1) -th column If a cell group consisting of four unit cells called unit cells is defined and the arrangement pattern of the first sub-region and the second sub-region is made common to all cell groups, the reference pattern formed is 2 rows. It becomes a repetitive pattern of a cell group composed of four unit cells arranged in two rows, and it becomes possible to ensure pseudo uniformity.

  On the other hand, in order to set the reference luminance to 25% or 75% with the conventional stripe-shaped reference pattern as shown in FIG. 10B, it is necessary to perform a row arrangement such as black black black white or black white white white. And pseudo uniformity is inevitably lowered.

(2) Features relating to the shape of the first attribute area Next, the first attribute area 10 in the test pattern shown in FIG. 10A and the first attribute area 50 in the test pattern shown in FIG. When the shapes are compared, the former is square, while the latter is circular. The inventor of the present application considers that the boundary line between the first attribute area and the second attribute area in the test pattern should be formed by a curve instead of a straight line. We believe that it is preferable to make the outline of one attribute region a circle or an ellipse. This is because when the boundary between the two regions is a straight line, a regular pattern becomes prominent in the vicinity of the straight line. As shown in FIG. 10A, when the shape of the first attribute region 10 is a square, a regular pattern is visually recognized along the square-shaped contour, which has a bad influence on the matching determination process. Will be affected. In particular, according to the present invention, not only brightness matching determination but also color matching determination must be performed, and elements that adversely affect the matching determination processing must be eliminated as much as possible.

(3) Feature of Distributing and Distributing First Attribute Areas at Multiple Locations A major feature of the test pattern shown in FIG. 19A is that the first attribute regions 50 are dispersed and arranged at multiple locations. The portion is a region 60 of the second attribute. That is, in the conventional test pattern shown in FIG. 10A, only one square-shaped first attribute region 10 is arranged at the center, whereas the test according to the present invention shown in FIG. In the pattern, a plurality of first attribute regions 50 each having a circular shape are arranged in a vertical and horizontal manner at a predetermined pitch.

  As described above, the reason why the first attribute areas 50 are distributed in a plurality of places is to make the total length of the boundary line between the first attribute area 50 and the second attribute area 60 as long as possible. In the measurement based on the basic principle of the present invention, it is essential to compare the brightness and color of the uniform pattern displayed in the first attribute area and the reference pattern displayed in the second attribute area. However, this comparison work becomes easier as the boundary between the two regions is longer. Actually, in the visual confirmation work by the operator, if the first attribute area 50 is melted into the second attribute area 60 and the boundary between the two becomes unrecognizable, the match recognition is performed. Therefore, in order to perform coincidence recognition with higher accuracy, it is preferable that the boundary line between both regions is longer.

  If the first attribute regions 50 are distributed at a plurality of locations, the total length of the boundary line can be increased accordingly. In fact, if the total length of the boundary line is compared between the test pattern shown in FIG. 10A and the test pattern shown in FIG. 19A, it can be easily understood that the latter is much longer. Contrary to the embodiment shown here, it is also possible to disperse and arrange the second attribute area at a plurality of locations and to set the background as the first attribute area (just in the 19th (a), Region 60 is the first attribute and region 50 is the second attribute).

  In practice, it is preferable to set the sum of the areas of the first attribute regions 50 to be equal to the sum of the areas 60 of the second attribute regions. For example, in the case of the test pattern shown in FIG. 19A, the first attribute area 50 is configured by a total of 12 circular areas, and the second attribute area 60 is determined by the background area in which the circular areas are arranged. In this case, it is preferable to set so that the total area of a total of 12 circles is equal to the area of the background region. This is a consideration for making the areas of the uniform pattern display area and the reference pattern display area to be compared with each other equal to each other so that equal comparison is performed. As in the present invention, in the case of performing color coincidence recognition as well as brightness, if one of the areas is larger, the vision is dragged toward the larger area, and strictly coincidence recognition is obtained. There is a risk that incorrect matching will be recognized. If the total area of both regions is the same, an equivalent comparison that eliminates such erroneous recognition is possible.

(4) Features related to the arrangement pitch of the first attribute area The major feature of the test pattern T1 according to the present invention shown in FIG. 19A is that the first (or second) attribute areas are distributed at a plurality of locations. As already mentioned. Here, the feature regarding this arrangement pitch is described.

  As will be described in detail later, it is known that human recognition sensitivity has a dependency on the spatial frequency of an object when the difference in brightness and color is visually recognized. Therefore, it is preferable to arrange an object to be visually confirmed at a predetermined spatial frequency that is considered to have high human recognition sensitivity. Accordingly, also in the test pattern shown in FIG. 19A, the first attribute region 50 is a region having the same shape and size, and a predetermined spatial frequency that is considered to have high human recognition sensitivity is obtained. It is preferable to disperse and arrange on a two-dimensional plane at a predetermined pitch so as to be obtained.

  FIG. 21 is a plan view showing an example in which a region 70 having the first attribute is formed by circles having the same radius r and arranged at a predetermined pitch on a two-dimensional plane. More specifically, first, a one-dimensional region array in which a plurality of first attribute regions 70 are arranged at a predetermined pitch Px in the horizontal direction is defined as a predetermined pitch Py in the vertical direction (where Py = √3 / 2 · Px ) And a plurality of adjacent one-dimensional regions arranged so that the phases are shifted by a half pitch. In other words, this two-dimensional plane is configured to be filled with a plurality of unit areas, with the illustrated hexagon as one unit area, and the center of each hexagon that constitutes each unit area and each of the unit areas. The centers of seven circles are arranged at the vertex positions.

  With this arrangement, the pitch of a pair of circles adjacent in the horizontal direction is always the pitch Px, and the pitch of a pair of circles adjacent in the diagonally up and down direction is always the pitch Px. A pair of adjacently arranged circles is always arranged at a constant pitch Px. Therefore, if the pitch Px is set to a pitch corresponding to a predetermined spatial frequency that is considered to have a high human recognition sensitivity, a test pattern having a preferable recognition sensitivity can be obtained.

As described above, when setting is made so that the sum of the areas of the first attribute area consisting of a circle is equal to the area of the second attribute area serving as the background portion, between the radius r and the pitch Px. Is a certain relationship. That is, within the hexagonal unit area, a condition is imposed that the area inside each circle (the gray area in the figure) is the same as the area outside each circle (the white area in the figure). Under such conditions, geometric area calculation
(Circle radius r) ≈ (Pitch Px) × (3/8)
The following approximate expression is derived.

  Next, as shown in FIG. 22, consider a model in which a pair of objects (circular first attribute regions) 70 are arranged at a pitch Px. A viewing angle when the pair of objects 70 is observed at a viewing distance L is θ. In general, the sensitivity of the visual system measured with respect to sine waves and rectangular wave patterns of various temporally constant frequencies presented spatially is expressed by spatial frequency characteristics MTF (Modulation Transfer Function) or contrast discrimination sensitivity characteristics. The sensitivity of the human visual system with respect to an object repeatedly arranged at a predetermined pitch depends on the viewing angle θ shown in FIG. For example, as shown in FIG. 23, “Haruki Sakata and Haruo Kanno: Spatial frequency characteristics of chromaticity in color vision (color difference discrimination threshold), Television Journal, Vol. 31 (1), pp. 29-35” A sensitivity characteristic graph of the human visual system is shown. The horizontal axis shows the spatial frequency (unit: cycle / deg) of the observation object on a logarithmic scale, and the vertical axis shows the relative sensitivity value of the human visual system that discriminates the light / dark difference and color difference of the object. is there.

  If the characteristics as shown in FIG. 23 are taken into consideration, the operator who views the test pattern has the same attribute at a predetermined pitch that can obtain a spatial frequency showing good sensitivity for both the light / dark difference characteristics and the color difference discrimination characteristics. If these areas are dispersedly arranged, a test pattern that can expect a more accurate measurement result can be configured.

  When each optimum value is extracted from the graph of FIG. 23, a table as shown in FIG. 24 is obtained. That is, when the optimum value of the light / dark difference discrimination characteristic (spatial frequency corresponding to the peak position of the graph indicated by the alternate long and short dash line) is obtained from the graph of FIG. 23, it becomes 2.5 [cycle / deg], and the yellow / blue difference discrimination characteristic When the optimum value (spatial frequency corresponding to the peak position of the graph indicated by the solid line) is obtained, it is 0.4 [cycle / deg]. As a compromise value of both characteristics, for example, a value of about 0.6 [cycle / deg] can be set. In fact, according to the graph shown in FIG. 23, a certain degree of sensitivity is obtained for each characteristic around a spatial frequency of 0.6, and if a test pattern in which the spatial frequency is set to a compromise value of 0.6 is formed, A good recognition sensitivity can be obtained to a certain degree both in the case of performing brightness matching recognition and in the case of performing color matching recognition.

  Note that the spatial frequency (unit: cycle / deg) and the viewing angle (unit: deg / cycle) are inversely related, and the viewing angle for each spatial frequency 2.5, 0.4, 0.6 shown in the table of FIG. Are 0.40, 2.50, and 1.67, respectively, as shown. This is because when the first attribute region 70 is arranged at a pitch Px such that the viewing angle θ shown in FIG. 22 is 0.40 deg, 2.50 deg, 1.67 deg, / It shows that a pattern with an optimal blue color discrimination characteristic and a compromise between both characteristics can be obtained.

However, between the viewing angle θ and the pitch Px, via the viewing distance L,
Px = 2L · tan (θ / 2)
Therefore, even if the viewing angle θ is determined, the pitch Px cannot be determined unless the viewing distance L is determined. However, in the case of a general monitor, the viewing distance of the operator will be maintained within a substantially constant range. For example, according to the VDT work guidelines issued by the National Personnel Authority issued on December 16, 2002, the visual distance should be 40 cm or more. Even in the actual work environment, there are slight differences depending on the size of the monitor. Although there is, it can be considered to be approximately 40 cm. Therefore, in practice, the viewing distance L is set to around 40 cm, and the pitch Px may be set so that a certain degree of good recognition sensitivity can be obtained for both the light / dark difference discrimination characteristics and the color difference discrimination characteristics.

  For example, when the viewing distance L is set to 40 cm, the pitch corresponding to the viewing angle θ = 1.67 deg indicating the compromise value of both characteristics shown in FIG. 24 is Px≈12 mm as a result of the calculation by the above formula. Therefore, in the case of the test pattern shown in FIG. 21, it is sufficient to set Px≈12 mm. In addition, in order to make the total sum of the areas of the first attribute region made of a circle equal to the area of the second attribute region which is the background portion, the above-described expression “r≈Px · 3/8” The radius of the circle should be r≈4.5 mm. Therefore, for example, in the case of a monitor in which the size of one pixel is 0.25 mm, a test pattern in which the radius of the circle is set to 18 pixels and the pitch Px is set to 48 pixels may be displayed.

  Strictly speaking, however, as shown in the table of FIG. 24, the optimum value of the light / dark discrimination characteristic and the optimum value of the color difference discrimination characteristic are different from each other. For a visual operator, a first pitch that provides a spatial frequency that exhibits good sensitivity for the light and dark discrimination characteristics, and a second pitch that provides a spatial frequency that exhibits good sensitivity for the color difference discrimination characteristics; Are set, and when the operator performs a brightness matching operation by the operator, a test pattern in which regions having the same attribute are distributed and arranged at the first pitch is displayed, and the operator performs the color matching recognition task. When a test pattern is displayed, a test pattern in which areas having the same attribute are distributed and arranged at the second pitch is displayed, and the test pattern to be displayed is displayed. Process is preferably performed as to switch the configuration of the over down.

  For example, in the table of FIG. 24, when the viewing distance L is set to 40 cm, the pitch and the radius of the circle corresponding to the viewing angle θ = 0.40 deg which is the optimum value of the light / dark difference discrimination characteristic are the pitch Px≈2.8 mm, The radius r≈1.1 mm. On the other hand, the pitch and radius of the circle corresponding to the viewing angle θ = 2.50 deg, which is the optimum value of the yellow / blue difference discrimination characteristic, are the pitch Px≈17.5 mm and the radius r≈6.6 mm. Therefore, if processing based on the flowchart shown in FIG. 16 is performed, when performing the “brightness match” recognition processing in steps S2 and S3, the pitch Px≈2.8 mm and the radius r≈1.1 mm. When a test pattern in which such circles are arranged is displayed and “color match” recognition processing is performed in steps S4 and S5, a circle having a pitch Px≈17.5 mm and a radius r≈6.6 mm is displayed. What is necessary is just to display the arranged test pattern.

  Actually, the task of recognizing the matching of brightness and color using a test pattern in which a large number of circles of this size are arranged is called “the task of matching the brightness and color of two areas” as an operator's feeling. Rather, it means “adjustment so that brightness and color unevenness do not occur in the entire test pattern”. That is, if the brightness and color do not match, it is felt that brightness and color unevenness occur in the cycle of the pitch Px. As described above, the visual measurement using the conventional test pattern shown in FIG. 10A and the visual measurement using the test pattern T1 of the present invention shown in FIG. The measurement using the test pattern of the present invention can obtain better results.

<<< §6. Configuration of measurement of gradation reproduction characteristics according to the present invention >>>
Next, the basic configuration of the tone reproduction characteristic measurement processing of the color monitor according to the present invention will be described with reference to the block diagram of FIG. As shown in the figure, the main components of the tone reproduction characteristic measurement processing of the color monitor according to the present invention are tone value designation means 210, reference pattern generation means 220, pattern display means 230, tone value fluctuation means 240, coincidence signal. The input unit 250 and the characteristic calculation unit 260 have a function of measuring the gradation reproduction characteristic of the monitor 207 by an operator's visual measurement operation.

  However, as shown in FIG. 1, the measurement apparatus according to the present invention can be realized by incorporating a predetermined program into the monitor characteristic measurement apparatus 101 connected to the monitor 207. Each component is actually realized by a program incorporated in the monitor characteristic measuring apparatus 101.

  The gradation value designating unit 210 is a component having a function of designating a combination of gradation values of the three primary colors RGB for displaying a uniform pattern with uniform brightness and color in the first attribute area 50. Yes, each gradation value of RGB is designated to the pattern display means 230. On the other hand, the reference pattern generation unit 220 includes, in the second attribute area 60, a first sub area in which the three primary colors RGB each have a minimum gradation value, a second sub area in which each of the three primary colors RGB has a maximum gradation value, Is a component having a function of generating a reference pattern having a predetermined reference luminance. In the case of the embodiment described in §5, the three reference patterns of FIG. 19B, FIG. 20A, and FIG. 20B are selectively selected according to the reference luminance necessary for measurement. Can be generated.

  Based on the data given from each of these components, the pattern display means 230 displays a test pattern T1 as shown on the screen of the monitor 207. This test pattern T1 is a pattern composed of a first attribute area 50 and a second attribute area 60 arranged so as to be in contact with each other. In particular, the color pattern shown here is shown in FIG. It is the same as the color pattern shown. That is, the circular first attribute region 50 is arranged in a two-dimensional plane at a predetermined pitch, and the background portion thereof constitutes the second attribute region 60. As already described, a uniform pattern based on the combination of RGB gradation values specified by the gradation value specifying means 210 is displayed in the first attribute area 50, and in the second attribute area 60, The reference pattern generated by the reference pattern generation unit 220 is displayed. Actually, a predetermined electric signal for displaying such a test pattern is given from the pattern display means 230 to the monitor 207.

  The gradation value changing means 240 has a function of executing a changing operation for changing each gradation value specified by the gradation value specifying means 210. This variation operation changes the brightness and color of the uniform pattern displayed in the first attribute area 50. As described in §2, the gradation value changing operation includes a brightness changing operation and a color changing operation. In the case of the embodiment described in §2, the gradation value changing unit 240 performs a brightness changing operation and a color changing operation by an operation input from the operator. In this case, the gradation value changing means 240 displays an operation panel as shown in FIG. 13 or 14 on the screen of the monitor 207 (usually beside the test pattern), and based on the operator's mouse operation or the like. Thus, a process of changing each gradation value specified by the gradation value specifying means 210 is performed so that the brightness and color change. On the other hand, as described in §3, in the case of the embodiment in which the changing operation is automatically executed, the brightness changing operation and the color are performed by the procedure based on the flowchart of FIG. 16 without waiting for the operation input from the operator. A fluctuating operation will be performed.

  The coincidence signal input unit 250 receives the first attribute region 50 and the second attribute from the operator who views the test pattern displayed on the screen of the monitor 207 in a state where the variation operation by the gradation value variation unit 240 is performed. It has a function of inputting a coincidence signal indicating that the brightness and color of the attribute area 60 coincide with each other. In the embodiment in which the brightness match and the color match are input separately, the match signal input means 250 includes a brightness match signal input means 251 and a color match signal input means 252. It will be. For example, the match button 30 shown in FIG. 13 and FIG. 14 is a button indicating that both the brightness and the color match, and a match signal indicating that both the brightness and the color are matched by an operation of clicking the match button 30. Is entered. On the other hand, the brightness match button 41 shown in FIG. 15 functions as a brightness match signal input means 251 that indicates brightness match, and the color match button 42 shown in FIG. 15 is a color match that indicates color match. It functions as the signal input means 252.

  The characteristic calculation means 260 receives each gradation value of RGB designated by the gradation value designation means 210 when a coincidence signal indicating that both brightness and color are coincident is inputted from the coincidence signal input means 250. Is recognized as the corresponding gradation value of each primary color corresponding to the reference luminance according to the area ratio between the first sub-region and the second sub-region constituting the reference pattern generated by the reference pattern generation means 220, Based on the reference luminance and the corresponding gradation value that are in a corresponding relationship with each other, a process for calculating a graph showing the gradation reproduction characteristics for each primary color is executed. The specific calculation method is as already described. Thus, a graph showing the gradation reproduction characteristics is output for each primary color of RGB. Here, for convenience of explanation, the gradation reproduction characteristic is shown as a graph indicating a continuous functional relationship, but the gradation reproduction characteristic obtained by the characteristic calculation unit 260 is not necessarily in the form of a graph. A format such as a numerical table indicating the correspondence between gradation values and luminance values may also be used.

Next, the white chromaticity measuring method of the present invention will be described in detail.
<<< §7. Measuring method of white chromaticity according to the present invention >>
FIG. 26 is a block diagram showing a basic configuration of white chromaticity measurement processing of the color monitor according to the present invention. The monitor characteristic measurement device (personal computer) 101 is a measurement device according to the present invention, and has a function of measuring the white chromaticity of the monitor 207 in consideration of the illumination environment of the installation location.

  The basic principle of the white chromaticity measuring method of the present invention is that a reference body RE showing white as a reference is prepared in advance, and the color of the test pattern T2 displayed on the screen of the monitor 207 is the reference body RE. The adjustment is made so that the color looks the same as the color. That is, in FIG. 26, the test pattern T2 drawn on the screen of the monitor 207 is a pattern displayed on the screen of the monitor 207 based on the signal given from the monitor characteristic measuring apparatus 101 side. The reference body RE is an actual object that is held by the operator's hand. The operator performs an operation of placing the reference body RE in the vicinity of the test pattern T2 and inputting the comparison result to the monitor characteristic measuring apparatus 101 while comparing the colors of both with the naked eye.

  The reference body RE may be any object as long as it is an object showing white as a reference. For example, a general card-like white paper can be used as the reference body RE. However, since it is preferable to always use the same reference body RE for a plurality of monitors at the time of measurement, it is preferable to use an object having a certain level of robustness as the reference body RE for practical use. For example, a white tile or the like can be used as a reference body RE having sufficient robustness in practice. Further, since the reference body RE is used as an index indicating the unified standard of “white”, it is preferable that the reference body RE be a physically white object as much as possible. From this point of view, a complete diffusion plate using barium sulfate is also suitable for use as the reference body RE. Of course, it is also possible to prepare a reference monitor as a reference and use a screen displayed in white on the reference monitor as the reference body RE. However, the white display of the reference monitor may change due to aging, and considering the size and weight of the device itself, it is inconvenient to handle and is not very practical. When the DTP operation for creating a printed material is performed on the monitor, it is preferable to match the white color on the printed material with the white color on the monitor. What is necessary is just to use it as the body RE. Then, even when the color of the paper is deviated from perfect white, it is possible to match the white on the printed matter (the color of the portion where no ink is adhered) with the white on the monitor.

  The white chromaticity measurement process according to the present invention is configured by a test pattern display means 410, a gradation value storage means 420, a comparison result input means 430, a gradation value fluctuation means 440, and a measurement result output means 450 as shown in the figure. Has been.

  The test pattern display means 410 is a component having a function of displaying the test pattern T2 on the screen of the monitor 207 to be measured. In the illustrated example, the test pattern T2 having a square area is displayed, but the size and shape of the displayed test pattern T2 are not particularly limited. However, as will be described later, it is preferable to display the test pattern T2 having substantially the same shape and size as the reference body RE to be used in performing the visual comparison by the operator. This is because, as a characteristic of the human eye, even if the color is the same, the color recognized perceptually varies depending on the size of the presented area.

  On the other hand, the gradation value storage means 420 stores combinations of gradation values of the three primary colors RGB. For example, if the gradation values of the three primary colors RGB are expressed by 8-bit data having a range of 0 to 255, the gradation value storage means 420 stores R = 255, G = 200, and B = 234. Therefore, a large gradation value is stored. The test pattern display unit 410 displays the test pattern T2 based on the combination of the gradation values of the three primary colors RGB stored in the gradation value storage unit 420. That is, the test pattern T2 is a pattern having a uniform color over the entire area, but the color is determined based on the gradation values of the three primary colors RGB stored in the gradation value storage means 420. Will be. When the gradation values R = 255, G = 200, and B = 234 are stored in the gradation value storage means 420 as in the above-described example, the entire area of the test pattern T2 has this gradation value. Will be displayed in the color corresponding to. Of course, even if the same gradation values R = 255, G = 200, and B = 234 are given, the actual physical color displayed as the test pattern T2 is different for each monitor.

  The gradation value changing means 440 has a function of performing a changing operation for changing the gradation value stored in the gradation value storage means 420 with time according to a predetermined rule. The specific contents of the changing operation will be described in detail later. By this changing operation, the gradation value in the gradation value storage means 420 changes from time to time, and of course on the screen of the monitor 207. The color of the displayed test pattern T2 also changes every moment. The operator performs an operation of comparing the color of the test pattern T2 that changes from time to time with the color of the reference body RE.

  The comparison result input unit 430 receives the color of the reference body RE and the test pattern from an operator who views the test pattern T2 displayed on the screen of the monitor 207 in a state where the variation operation by the gradation value variation unit 440 is performed. It fulfills the function of inputting a comparison result for which the color of T2 is to be compared. When the comparison result indicating that the two colors to be compared are matched is input from the operator, a coincidence signal is given to the measurement result output means 450.

  When the coincidence signal is given from the comparison result input unit 430 (that is, when the operator inputs a comparison result indicating that the two colors to be compared match), the measurement result output unit 450 A measurement result indicating white chromaticity based on a reference body RE in the current illumination environment of the monitor 207 using a combination (for example, Rw, Gw, Bw) of the gradation values of the three primary colors RGB stored in the value storage unit 420 Output as.

  After all, the gradation values Rw, Gw, and Bw output from the measurement result output means 450 are the same color as the reference body RE under the current illumination environment when the gradation values are given to the monitor 207 to be measured. It is shown that the color display observed as. For example, if the results of Rw = 255, Gw = 205, and Bw = 180 are output, in order to display a white color equivalent to the reference body RE on the display screen of the monitor 207 under the current illumination environment. Indicates that a combination of gradation values of R = 255, G = 205, and B = 180 may be given. Of course, the specific values of the gradation values Rw, Gw, and Bw obtained as measurement results differ for each color monitor installed in each lighting environment, but at least for each color monitor, If the gradation values Rw, Gw, and Bw obtained as measurement results are given, a white color equivalent to the reference body RE observed in the illumination environment can be obtained.

  Therefore, the measurement result by the white chromaticity measurement process according to the present invention is useful in the case of performing the DTP process for creating a commercial print by the division of labor of many staffs. Each staff member uses a color monitor having a unique characteristic under a unique lighting environment, and all staff members use a common reference body RE to measure monitor characteristics according to the present invention. If the measurement is performed by the device 101 and the obtained white chromaticity profile data is incorporated into each personal computer and correction is performed, any staff can determine whether the indoor lighting is a fluorescent light bulb or a light bulb, and the indoor wallpaper. The color image based on the same white color can be seen on the respective monitor for visual sense without being influenced by conditions such as color or whether sunlight is inserted. .

  Of course, in the profile data obtained by using the reference body RE having different white characteristics at the time of measurement, such uniformity cannot be obtained. For example, a complete diffusion plate made of barium sulfate is used as a standard reference body RE. If the arrangement is used, it is possible to obtain profile data having a fairly wide unity without necessarily using the physically same object as a reference body.

  Next, a specific change operation by the gradation value changing unit 440 and a specific input method of the comparison result to the comparison result input unit 430 will be described. As described above, the gradation value changing unit 440 is a component that performs a changing operation for changing the gradation value stored in the gradation value storage unit 420 with time according to a predetermined rule. However, in practice, the gradation values of a plurality of primary colors are not changed at the same time, but one of the three primary colors RGB is selected as a specific color, and the gradation value for one specific color is changed at a time. This makes it easier for the operator to perform comparison work. In this case, the operator can independently determine the optimum gradation value for matching with the color of the reference body RE for each of the three primary colors RGB.

  FIG. 27 is a plan view showing an example of an operation panel used for performing such work. Here, the buttons 81 to 83 are change start buttons for the three primary colors R, G, and B, the button 84 is a change stop button common to the three primary colors, and the button 85 is a match button. Here, the change start buttons 81 to 83 and the change stop button 84 are buttons used by the operator to give a change instruction to the gradation value changing means 440, and the match button 85 is used by the operator to input a comparison result. This is a button used to input a comparison result indicating a match to the means 430. These buttons are displayed on the display screen of the monitor 207 together with the test pattern T2, and can be pressed by clicking with a mouse pointer or the like.

  When the operator clicks the change start button 81, the gradation value changing means 440 changes the gradation value R stored in the gradation value storage means 420 in accordance with the change instruction from the operator. To start. Specifically, a fluctuation operation for adding or subtracting a predetermined fluctuation amount at a predetermined cycle to the gradation value R is started. For example, when the initial value of the gradation value R stored in the gradation value storage means 420 is R = 100, the predetermined period is 1 second, and the variation amount is 5, the variation start button 81 is pressed. By clicking, R = 105, 110, 115... Changes every second. Naturally, the color of the test pattern T2 on the monitor 207 also gradually changes. The change stop button 84 is a button for stopping such a change operation, and can give an instruction to stop the change operation to the gradation value changing means 440.

  Similarly, the change start button 82 is a button for giving an instruction to start the change operation for changing the gradation value G to the gradation value changing means 440, and the change start button 83 is the gradation value changing means 440. Is a button for giving an instruction to start a changing operation for changing the gradation value B.

  It should be noted that such a gradation value changing operation is continued forever until the change stop button 84 is clicked by cyclically changing or reciprocally changing the gradation value within a range of 0 to 255 gradation values. To be done. FIG. 28 is a diagram for explaining the circulation fluctuation and the reciprocation fluctuation. In the illustrated example, the range from the minimum gradation value 0 to the maximum gradation value 255 is set as the fluctuation range L.

  As shown in FIG. 28 (1), the fluctuation operation due to the cyclic fluctuation is performed when the gradation value obtained by the fluctuation operation for adding the fluctuation amount exceeds the maximum gradation value 255 of the fluctuation range L. In the case where the gradation value obtained by the fluctuation operation for subtracting the fluctuation amount is less than the minimum gradation value 0 of the fluctuation range L, the cyclic processing of counting from the minimum gradation value 0 side of L is performed. A circulation process of counting from the maximum gradation value 255 side is performed. For example, if the gradation value increases to 245 and 250 and reaches 255 due to the variation operation of adding the variation amount S = 5, then when 5 is added, it becomes 260. In this case, 256 is subtracted, the next gradation value is set to 4, and 9, 14, 19,... In the case of subtracting the fluctuation amount S = 5, conversely, it may be circulated as 19, 14, 9, 4, 255, 250.

  On the other hand, as shown in FIG. 28 (2), when the gradation value obtained by the variation operation for adding the variation amount exceeds the maximum gradation value 255 of the variation range L, On the contrary, the gradation value obtained by the fluctuation operation for subtracting the fluctuation amount is less than the minimum gradation value 0 of the fluctuation range L. In this case, a loopback process is performed to switch from the minimum gradation value 0 side to a changing operation for adding a changing amount. For example, if the gradation value increases to 245,250 and reaches 255 by the variation operation of adding the variation amount S = 5, then when 5 is added, it becomes 260. In this case, In this case, when the value reaches 255, the change amount 5 is subtracted and the return processing is performed so that the next gradation value is 250, 245, 240,. Then, when the gradation value reaches 15, 10, 5, 0, it may be turned again to add the fluctuation amount 5 and folded back to 5, 10, 15,.

  When any one of the change start buttons 81, 82, and 83 shown in FIG. 27 is clicked, the gradation value of the corresponding primary color will circulate or reciprocate within the change range of 0 to 255. Thus, it becomes possible to grasp a rhythm in which the test pattern T2 repeatedly fluctuates at a constant period. If such a rhythm can be grasped, when the color of the test pattern T2 and the color of the reference body RE are closest, the operation of clicking the variation stop button 84 can be performed relatively easily.

  In the case of this embodiment, the gradation value changing operation is always performed as an operation for changing only the gradation value of any one of the three primary colors RGB, so that the change start buttons 81, 82, and 83 are used. After clicking on any of them and changing the gradation value of a specific color, click on the change stop button 84 and stop changing operation related to the specific color. The mechanism is such that the change start button does not function, or when the change start button for the second specific color is clicked while the change operation for the first specific color is being performed, the first It is preferable that the change operation for the specific color is automatically stopped and the change operation for the second specific color is started.

  In this way, the gradation value changing means 440 starts and stops a changing operation for adding or subtracting a predetermined fluctuation amount at a predetermined cycle to a gradation value of a predetermined primary color in accordance with a fluctuation instruction given from an operator. If the function is provided, the operator can give an instruction to start or stop the changing operation with respect to a desired primary color among the three primary colors RGB as necessary, and the color of the test pattern T2 can be changed to the reference body RE. It is possible to work to bring it closer to the color. Then, finally, when it becomes possible to recognize that the comparison targets match, the match button 85 may be clicked.

  In the present application, “colors match” or “colors are the same” does not necessarily mean a state in which it is recognized that two colors completely match, but in a state where one color is changed. It also means a state where the recognition that the two are closest is obtained. Therefore, the operator may perform an operation of clicking the match button 85 at the moment when the user feels that the two colors are closest while comparing the test pattern T2 whose color is changing and the reference body RE. When the match button 85 is clicked, a comparison result indicating that the comparison object matches is input to the comparison result input unit 430, and the comparison result input unit 430 outputs the comparison result to the measurement result output unit 450. , A coincidence signal is given. As described above, the measurement result output unit 450 performs the process of outputting, as the measurement result, the gradation values Rw, Gw, and Bw of the three primary colors RGB stored in the gradation value storage unit 420 at this time. It is.

  However, in practice, the form in which the gradation values of the three primary colors RGB are changed using an operation panel as shown in FIG. 27 is not necessarily good for the operator. The reason is that there are three parameters to be changed: primary colors R, G, and B. Actually, considerable skill is required to adjust the three parameters so as to match the color of the test pattern T2 with the color of the reference body RE. Even though a general operator can recognize that the two do not match, it is difficult to grasp which primary color gradation value will change if both are matched. is there.

  Therefore, in practice, it is preferable that the gradation operation of any one of the primary colors is fixed to the maximum gradation value, and the changing operation is performed so as to change only the gradation values of the remaining two primary colors. In the first place, white is theoretically a color obtained by maximizing the light emission luminance of each primary color. Therefore, the gradation value of at least one primary color among the three primary colors RGB is set to the maximum gradation value. Is preferred. Therefore, no trouble occurs even if the gradation value of one primary color is always fixed to the maximum gradation value.

  The inventor of the present application has found that there is a common tendency when the white characteristics of various types of color monitors commercially available from a number of manufacturers are examined in various lighting environments. In any case, the colors displayed on the screen when each of the three primary colors RGB is set to the maximum gradation value (that is, the gradation values R = 255, G = 255, and B = 255 are given). Is the fact that it tends to be slightly greener or slightly bluer than the original white color and will never be observed as reddish. In other words, in any case, in order to display white, the gradation value of the primary color G is slightly decreased from the state of R = 255, G = 255, and B = 255, or the floor of the primary color B is displayed. It is sufficient to slightly reduce the key value.

  Considering this fact, in practice, the primary color R of the three primary colors RGB is always fixed at the maximum gradation value R = 255, and the gradation value changing operation is performed only for the primary color G and the primary color B. It is reasonable to do so. FIG. 29 is a plan view showing an example of the operation panel from such a viewpoint. In this operation panel, only a start button 91 and two coincidence buttons 92 and 93 are provided, and the operator does not need to have the concept of the three primary colors RGB. An explanatory text is displayed beside each button, and the operator may perform an operation of clicking the button according to the explanatory text.

  First, the operator clicks the start button 91 in accordance with the explanatory text “Step 0: Press when starting measurement”. Then, the changing operation for the primary color G starts. At this time, the gradation values of the primary colors R and B remain fixed. When the operator recognizes that the same color as that of the reference body RE is observed while looking at the test pattern T2 during the changing operation, according to the explanatory note “Step 1: Please press when the colors become the same”, the match button 92 is displayed. Click. Then, the changing operation for the primary color B is started. At this time, the gradation values of the primary colors R and G remain fixed. That is, when the match button 92 is clicked, the changing operation for the primary color G is stopped, and the gradation value at the time of the stop is maintained as it is. When the operator recognizes that the same color as that of the reference body RE is observed while looking at the test pattern T2 during the variation operation for the primary color B, the operator follows the explanatory note “Step 2: Press when the colors are the same”. Click the match button 93.

  By the above operation, the optimum gradation value Gw for the primary color G and the optimum gradation value Bw for the primary color B for matching the color of the test pattern T2 and the color of the reference body RE are determined by the operator's button operation. Determined by At this time, the primary color R remains fixed at the maximum gradation value R = 255, and the optimum gradation value for the primary color R is always Rw = 255.

  In this manner, in the example using the operation panel shown in FIG. 29, the gradation value changing means 440 adds or reduces a predetermined fluctuation amount at a predetermined cycle to the gradation value of a specific primary color to be changed. In addition to performing the changing operation, a process of switching a specific primary color to be changed according to the comparison result input to the comparison result input unit 430 is performed. That is, the match button 92 is a button for inputting a comparison result indicating that the color of the test pattern T2 and the color of the reference body RE match (or approach each other). It also functions as a button for giving an instruction to switch to a variable operation.

  Eventually, in order to be able to perform measurement using the operation panel shown in FIG. 29, a predetermined fluctuation amount is added to the gradation value changing means 440 at a predetermined cycle with respect to the gradation value of the primary color G. Alternatively, a comparison result input unit 430 is provided with a function of selectively performing a green variation operation for reducing and a blue variation operation for adding or subtracting a predetermined variation amount with respect to the gradation value of the primary color B in a predetermined cycle. Includes a green approximation signal indicating that the color of the reference body RE and the color of the test pattern T2 are closest to each other in a state where the gradation value changing unit 440 is performing the green changing operation, and the tone value changing unit 440. In the state of performing the blue variation operation, a function to input from the operator a blue approximation signal indicating that the color of the reference body RE and the color of the test pattern T2 are the closest is provided. There. Then, when both the blue approximate signal and the green approximate signal are input to the comparison result input unit 430, the comparison result indicating that the comparison target is matched is handled as input, and the measurement result output unit 450 is processed. Thus, a coincidence signal may be given.

  FIG. 30 is a flowchart showing a measurement procedure using the operation panel shown in FIG. First, in step S11, the gradation value of each primary color is set to an initial value. In this example, the initial value of the primary color R is 255, but the initial value G0 of the primary color G and the initial value B0 of the primary color B may be arbitrary values. Subsequently, in step S12, it is detected whether or not the start button 91 has been pressed. When the start button 91 is pressed, a green variation operation is executed in step S13. That is, the gradation value of the primary color G is increased or decreased by a predetermined fluctuation amount. At this time, circulation processing or loopback processing is performed as necessary. In step S14, it is detected whether or not the match button 92 has been pressed, and the green variation operation in step S13 is repeatedly executed until the match button 92 is pressed. The loop processing in steps S13 and S14 is set to be executed at a predetermined cycle such as a one-second cycle.

  Eventually, when the coincidence button 92 is pressed, a blue variation operation is executed in step S15. That is, when the coincidence button 92 is pressed, a green approximate signal is given to the comparison result input means 430, the green variation operation that has been performed so far is stopped, and the gradation value of the primary color G is The value is fixed at that time. Then, the fluctuation operation for the gradation value of the primary color B that has been fixed so far is started. That is, the gradation value of the primary color B is increased or decreased by a predetermined fluctuation amount. At this time, circulation processing or loopback processing is performed as necessary. In step S16, it is detected whether or not the match button 93 has been pressed, and the blue variation operation in step S15 is repeatedly executed until the match button 93 is pressed. The loop processing in steps S15 and S16 is also set to be executed at a predetermined cycle such as a one-second cycle.

  Thus, when the match button 93 is pressed, step S17 is executed. That is, when the coincidence button 93 is pressed, a blue approximate signal is given to the comparison result input means 430, the blue variation operation that has been performed so far is stopped, and the gradation value of the primary color B is The value is fixed at that time. Then, a coincidence signal is given from the comparison result input means 430 to the measurement result output means 450. Upon receiving this coincidence signal, the measurement result output means 450 performs a process of outputting each gradation value of the primary colors RGB stored in the gradation value storage means 420 at that time as a measurement result.

  In the measurement procedure shown in the flowchart of FIG. 30, the operator determines the gradation value of the primary color G by clicking the match button 92 in step S14, and determines the gradation value of the primary color B by clicking the match button 93 in step S16. Thus, the gradation values Gw and Bw determined in these steps and the gradation value Rw (= 255) fixed from the beginning are output as measurement results. Even in such a method, the gradation value circulates or reciprocates during each color variation operation, so the operator can click the match button when the color is closest, and is optimally accurate to some extent. It is possible to determine a simple gradation value.

  However, in consideration of more practical operation, rather than determining the gradation values of the primary colors G and B with a single click operation, the operator is given a chance when making the final determination. It is preferable to do this. The measurement procedure shown in the flowchart of FIG. 31 shows an embodiment that takes such points into consideration. In this embodiment, the gradation value of the primary color R is fixed to the maximum gradation value 255, but the gradation values of the primary colors G and B are determined by a plurality of click operations by the operator. .

  First, in step S21, the gradation value of each primary color is set to an initial value. Again, the initial value of the primary color R is 255, but the initial value G0 of the primary color G and the initial value B0 of the primary color B may be arbitrary values. Here, for convenience of explanation, it is assumed that G0 = 200 and B0 = 200 are set. In step S21, an initial value S0 of the fluctuation amount S of the fluctuation operation and an initial value L0 of the fluctuation range L are also set. Here, it is assumed that S0 = 10 and L0 = 0 to 255.

  Subsequently, in step S22, it is detected whether or not a mouse click has been performed. In this embodiment, a plurality of buttons are not displayed as in the previous embodiments, but only a single button is displayed on the screen. In other words, this single button serves as a step transition button for shifting the measurement procedure to the next step. Therefore, the operator need only perform an operation of clicking the single button with a mouse or the like, and does not need to select the button. Further, without displaying a specific button at all, it may be recognized that the click operation is performed regardless of the position of the mouse click on the screen. Of course, the operation of the operator is not necessarily limited to the mouse click. For example, an operation of pressing the space key of the keyboard may be used instead of the mouse click operation.

  When a click is detected in step S22, a green variation operation is executed in step S23. That is, the gradation value of the primary color G is increased or decreased by the value of the fluctuation amount S at that time. At this time, cyclic processing or loopback processing is performed as necessary. The fluctuation range L serving as a reference for the cyclic processing or loopback processing is a set value at that time. Here, for convenience of explanation, an example will be described in which a fluctuation operation that always increases by the fluctuation amount S is always performed, and when the fluctuation range L is exceeded, a circulation process is always performed. In the above example, the variation amount S is set to the initial value S0 = 10, and the variation range L is also set to the initial value L0 = 0 to 255. Therefore, in step S23, first, the gradation value of the primary color G is set. However, the initial value 200 is updated to 210, and the update process of increasing by 10 is continued until the maximum gradation value 255 is exceeded.

  Thus, until the click is detected in step S24, the process of looping steps S23 and S24 is repeatedly executed, and the gradation value of the primary color G is 220, 230, 240, 250,. Updates are made incrementally. When the gradation value 260 is updated at the next stage, it exceeds the maximum gradation value 255 of the fluctuation range L. Therefore, by subtracting 256 to perform the cyclic processing, a new gradation is obtained. Processing for setting the value to 4 is performed, and thereafter, updating is performed to increase the variation amount S = 10 by 14, 24, 34,. At this time, the primary colors R and B remain fixed at R = 255 and B = 200, respectively.

If such an update process is performed at a cycle of 1 second, for example, the gradation value of the primary color G will go around in about 25 seconds, and the operator will change the color of the test pattern T2 at a cycle of about 25 seconds. You can observe how it fluctuates. Then, when it is felt that the color of the test pattern T2 is closest to the color of the reference body RE, a click operation is performed. Here, as an example, it is assumed that the click operation by the operator is performed when the primary color G = 193, and the following description will be continued.

  If a click is detected in step S24, a blue variation operation is executed in step S25. The click operation in step S24 has a meaning of inputting a green approximate signal to the comparison result input unit 430 and instructing the gradation value changing unit 440 to switch the primary color to be changed. As a result, the changing operation of the primary color G is stopped, and the gradation value of the primary color G maintains the state of G = 193. Then, a changing operation is performed in which the gradation value of the primary color B is increased by the value of the changing amount S = 10. At this time, the other primary colors remain fixed at R = 255 and G = 193.

  Thus, in step S26, the process of looping steps S25 and S26 is repeatedly executed until the next click is detected, and the gradation values of primary color B are 210, 220, 230, 240, 250, 4, 14 , 24... And the amount of variation S = 10 are continuously updated by the circulation variation. The operator performs a click operation again when he feels that the color of the test pattern T2 is closest to the color of the reference body RE. Here, as an example, the following description will be continued assuming that the click operation by the operator is performed when the primary color B = 231. At this time, the gradation value of each primary color stored in the gradation value storage means 420 is R = 255, G = 193, and B = 231.

  If a click is detected in step S26, the process proceeds to step S27. The click operation in step S26 has a meaning of inputting a blue approximate signal to the comparison result input unit 430 and instructing the gradation value changing unit 440 to switch the primary color to be changed. That is, the processing from step S23 is executed again through steps S27 and S28, the primary color B changing operation is stopped, and the primary color G changing operation is restarted. However, in the second round procedure, the fluctuation amount S and the fluctuation range L are updated. Specifically, in step S28, an update process for reducing both the fluctuation amount S and the fluctuation range L is executed. Here, it is assumed that the second round has been updated such that the fluctuation amount S = 3 and the fluctuation range L = ± 30. Note that the fluctuation range of L = ± 30 means a range having a width of 30 above and below centering on the current gradation value.

  In the second loop of steps S23 and S24, the gradation value of the primary color G is updated to increase by a new variation amount S = 3. Therefore, in the case of the above-described example, updating such as G = 193, 196, 199, 202... Is performed. However, since the variation range L = ± 30 is newly set, the specific variation range has a width of ± 30 centering on the initial gradation value G = 193 of the primary color G in the second round, and 163-3 The range is 223. After all, in the second round, the gradation value of the primary color G circulates and fluctuates every 3 steps within the fluctuation range of 163 to 223.

  Similarly, in the second loop of steps S25 and S26, the gradation value of the primary color B is updated to be increased by a new variation amount S = 3. Therefore, in the case of the above example, updating such as G = 231, 234, 237, 240... Is performed. However, since the variation range L is set to a new value of ± 30, the specific variation range has a width of ± 30 centering on the initial gradation value G = 231 of the primary color B in the second round. 261 (actually, the range of 256 to 261 is replaced with 0 to 5 due to cyclic variation), and the gradation value of the primary color B circulates and fluctuates every 3 steps within this variation range. Become.

  Such processing is repeatedly executed until it is determined in step S27 that the fluctuation amount S has reached the specified value. For example, if the fluctuation amount S = 1 is set to a specified value, the update in step S28 is performed until the fluctuation amount S reaches 1, and the processes in steps S23 to S26 are repeated.

  The update range in step S28 may be any setting as long as the fluctuation amount S and the fluctuation range L are gradually reduced. For example, for the fluctuation amount S, for example, , “10” → “3” → “1” is set in advance, and the fluctuation range L is expressed as “all range (0 to 255)” → “± 30” → “± 7”. What is necessary is just to set an update value. In this case, the first round is processed with settings of S = 10 and L = 0 to 255, the second round is processed with settings of S = 3 and L = ± 30, and the third round is Processing is performed with the setting of S = 1, L = ± 7. When the third round is completed, it is determined in step S27 that S has reached the specified value, and the process proceeds to step S29. Become.

  Thus, when it is determined in step S27 that S has reached the specified value, the comparison result input unit 430 gives a coincidence signal to the gradation value changing unit 440. Then, as shown in step S29, the measurement result output unit 450 outputs the gradation values of the three primary colors RGB currently stored in the gradation value storage unit 420 as measurement results Rw, Gw, and Bw. Is executed.

  In order to execute the measurement procedure as shown in FIG. 31, when the green approximate signal is input to the gradation value changing means 440 while the green changing operation is being performed, the blue changing operation is started. When the blue approximate signal is input in the state where the variation operation is being performed, the green variation operation is started, and the function to execute the green variation operation and the blue variation operation alternately and repeatedly is provided. What is necessary is just to give the function to perform repeatedly, reducing the fluctuation amount S and the fluctuation range L gradually. The comparison result input means 430 also compares the comparison result indicating that the comparison object is matched when the input of both the green approximate signal and the blue approximate signal is completed after the fluctuation amount S reaches a predetermined specified value. It is sufficient to provide a function for outputting a coincidence signal.

  In this way, in the measurement process shown in FIG. 31, the operator can repeatedly execute the color matching recognition input while gradually decreasing the gradation value variation amount S and the variation range L. Compared with the measurement process, it is possible to obtain a measurement result with higher accuracy. That is, as the first round, the second round, and the third round are repeated, the gradation values of the primary colors G and B gradually approach optimum values. Further, since the fluctuation amount S of the gradation value is gradually reduced, the step width of the fluctuation operation is initially rough and gradually becomes finer, and the fluctuation range L is also gradually narrowed. As a result, the gradation value is gradually narrowed down to the optimum value, and an efficient measurement operation becomes possible.

  In this measurement process, the operability as viewed from the operator side is extremely high. As described above, since the operator's operation is merely a mouse click, the operation can be performed while gazing at the test pattern T2 and the reference body RE. In short, the operator only has to repeat clicking the mouse at the moment when both colors feel the closest, and in the case of the above example, the click operation is performed a total of six times. If done, the measurement will be completed automatically. In practice, every time a click operation is performed, the operator is presented with some sound, or some message is displayed on the screen, so that six measurements are repeated. It is preferable to make it recognized and to make it possible to clearly grasp each break.

  As described above, with reference to FIGS. 30 and 31, the primary color R of the three primary colors RGB is always fixed at the maximum gradation value R = 255, and the gradation value changing operation is performed only for the primary color G and the primary color B. An example of performing was described. Here, an embodiment based on another approach will be described.

  Another approach described here is based on the general perception of human color where the opposite color of red is green and the opposite color of yellow is blue. That is, according to human perception, the balance of red or greenish is one measure of color, and the balance of yellowish or blueish is another measure of color. Yes. The present inventor uses such human perception of color to perform white recognition work from the viewpoint of whether it is reddish or greenish, and white recognition work from the viewpoint of whether it is yellowish or bluish. By doing so, it was found that measurement work that more closely matches human perception becomes possible.

  That is, first, the display color of the test pattern T2 is changed such that the green color is gradually diminished from the green state, then the white color is gradually changed to light red, and the red color is gradually increased. On the other hand, if you change the red color gradually from the red state, then turn white to light green, and gradually increase the green color, it will not be reddish but greenish. It is possible to recognize white as an intermediate point between red and green. Here, such a variation operation is referred to as a red / green variation operation. In this red / green variation operation, the color recognized by the operator as white has a meaning as a color neutralized by the opposite color component of red / green.

  On the other hand, the display color of the test pattern T2 is changed from gradually changing from a yellow state to gradually decreasing the yellow color, then gradually changing to a light blue color through the white color, and gradually increasing the blue color. If you change the color from blue to gradually fade away from blue, then gradually turn white to light yellow and gradually strengthen yellow, yellow and not bluish As a middle point of blue, white can be recognized. Here, such a changing operation is called a yellow / blue changing operation. In this yellow / blue variation operation, the color recognized by the operator as white has a meaning as a color obtained by neutralizing the opposite color component of yellow / blue.

  After all, in the state where the display color of the test pattern T2 is changed by the above-described red / green changing operation, a signal indicating that the colors match is input from the operator, and further, the display pattern is changed by the above-described yellow / blue changing operation. In this state, if a signal indicating that the colors match is input from the operator, a color neutralized with respect to both the opposite color component of red / green and the opposite color component of yellow / blue can be obtained. It is possible to obtain a highly accurate measurement result that matches the perception of.

  When taking such an approach, the procedure shown in the flowcharts of FIGS. 30 and 31 may be slightly modified. First, in step S11 of FIG. 30, the gradation values of the three primary colors RGB are respectively set to predetermined initial values. In this embodiment, the primary color R is not fixed and is subject to change in gradation value. In step S12, when it is detected that the start button 91 has been pressed, the measurement work starts in exactly the same way as in the previous embodiment. However, in step S13, the above-described red / green variation operation is performed instead of the green variation operation. For this reason, when the match button 92 is pressed in step S14, color matching is obtained in terms of the balance of the opposite color components of red / green. Here, the signal obtained by operating the coincidence button 92 in step S14 is referred to as a red / green approximate signal.

  On the other hand, in step S15, the yellow / blue variation operation described above is performed instead of the blue variation operation. For this reason, when the match button 93 is pressed in step S16, color matching is obtained in terms of the balance of the opposite color components of yellow / blue. Here, the signal obtained by operating the match button 93 in step S16 is referred to as a yellow / blue approximate signal. Thus, if a red / green approximate signal is obtained in step S14 and a yellow / blue approximate signal is obtained in step S16, both the opposite color component balance of red / green and the opposite color component balance of yellow / blue are also obtained. Since the color match is obtained, finally, in step S17, the gradation values of the three primary colors RGB at that time are output as measurement results.

  In step S13, in order to perform the red / green variation operation, a predetermined variation amount is added to or subtracted from the gradation value changing means 440 with respect to the gradation value of the primary color R at a predetermined period, or the primary color G is changed. A function of performing a change for adding or subtracting a predetermined fluctuation amount at a predetermined cycle to the gradation value may be provided. In order to adjust the balance of the opposite color components of red / green, the gradation value of the primary color R may be increased or decreased, and the gradation value of the primary color G may be increased or decreased. Since the two are opposite colors, in performing the balance adjustment between them, the changing operation for increasing the gradation value of the primary color R is equivalent to the changing operation for decreasing the gradation value of the primary color G. The changing operation for increasing the gradation value of G and the changing operation for decreasing the gradation value of the primary color R are equivalent.

  Therefore, for example, if the maximum gradation value is reached as a result of gradually increasing the gradation value of the primary color R (for example, R = 255), the gradation value of the primary color G is gradually increased. By reducing the amount, it is possible to continue the change in the same adjustment direction in which the redness is strengthened and the greenness is weakened visually. Similarly, when the gradation value of the primary color R is gradually decreased and reaches the minimum gradation value (for example, R = 0), the gradation value of the primary color G is gradually increased. By doing so, it is also possible to continue the fluctuation in the same adjustment direction, in which the greenness is enhanced and the redness is decreased visually.

  As described above, in principle, the red / green variation operation can be performed by either a method of increasing or decreasing the gradation value of the primary color R or a method of increasing or decreasing the gradation value of the primary color G. In practice, it is preferable to repeatedly and alternately execute the operation of changing the gradation value of the primary color R and the operation of changing the gradation value of the primary color G. For example, when the gradation value of the primary color R is gradually increased to reach the maximum gradation value (for example, R = 255), an operation of gradually decreasing the gradation value of the primary color G is performed. . When the gradation value of the primary color G reaches the minimum gradation value (for example, G = 0), this time, the gradation value of the primary color R is gradually decreased, and the gradation value of the primary color R is minimized. When the value reaches the value (for example, R = 0), the gradation value of the primary color G is gradually increased in the future. When the gradation value of the primary color G reaches the maximum gradation value (for example, G = 255), the gradation value of the primary color R is gradually increased. In this way, if the change in the primary color R and the change in the primary color G are alternately performed, the operator can alternately turn reddish, greenish, reddish, greenish → reddish or greenish. It is possible to present a test pattern that changes with time, and to change the gradation value of each color in the entire range from the maximum gradation value to the minimum gradation value.

  On the other hand, in order to perform the yellow / blue variation operation in step S15, in principle, a predetermined variation amount is added to or subtracted from the gradation value of the primary color Y in a predetermined cycle to the gradation value variation means 440. Alternatively, it is sufficient to provide a function of performing a change in which a predetermined change amount is added to or reduced from the gradation value of the primary color B at a predetermined period. In order to adjust the balance of the opposite color components of yellow / blue, the gradation value of the primary color Y may be increased or decreased, and the gradation value of the primary color B may be increased or decreased. Since both are opposite colors, in performing the balance adjustment between them, the variation operation for increasing the gradation value of the primary color Y and the variation operation for decreasing the gradation value of the primary color B are equivalent. The changing operation for increasing the gradation value of B is equivalent to the changing operation for decreasing the gradation value of the primary color Y.

  However, in practice, since the three primary colors of the color monitor are RGB and the primary color Y component is not included, it is not possible to perform a changing operation that directly increases or decreases the gradation value of the primary color Y. Therefore, in this embodiment, paying attention to the fact that the primary color Y is obtained as a mixed color of the primary color R and the primary color G, the combination of the primary color R and the primary color G is used in place of the primary color Y, so that it is based on the principle described above. The yellow / blue variation operation is performed.

  Specifically, the gradation value changing means 440 adds or reduces a predetermined amount of change simultaneously with a predetermined period to the gradation value of the primary color R and the gradation value of the primary color G, or It is sufficient to provide a function of performing a variation in which a predetermined variation amount is simultaneously added to or subtracted from the adjustment value at a predetermined cycle. In order to adjust the balance of the opposite color components of yellow / blue, the gradation values of the primary color R and the primary color G may be increased or decreased simultaneously by the same amount (substantially increasing or decreasing the gradation value of the primary color Y). The gradation value of the primary color B may be increased or decreased. Since the primary color Y (mixed color of the primary color R and the primary color G) and the primary color B are opposite colors, when adjusting the balance between the primary color Y and the primary color, a change operation that increases the gradation values of the primary colors R and G by the same amount simultaneously. The variation operation for decreasing the gradation value of B is equivalent, and similarly, the variation operation for increasing the gradation value of the primary color B and the variation operation of simultaneously decreasing the gradation values of the primary colors R and G by the same amount. Become equivalent.

  Therefore, for example, the gradation values of the primary colors R and G are changed from (R = 200, G = 100) → (R = 205, G = 105) → (R = 210, G = 110) → (R = 215, G = 115) →... If at least one of them has reached the maximum gradation value (for example, R = 255, G = 155) as a result of gradually increasing, then the floor of the primary color B By gradually decreasing the tone value, for example, B = 120 → 115 → 110 → 105 →..., Visually, fluctuations in the same adjustment direction of increasing yellowness and decreasing blueness are achieved. It is possible to continue. Similarly, the gradation values of the primary colors R and G are gradually decreased as (R = 200, G = 100) → (R = 195, G = 95) → (R = 190, G = 90) →. As a result, when at least one of them reaches the minimum gradation value (for example, R = 100, G = 0), the gradation value of the primary color B is now changed, for example, B = 120 → 125. By gradually increasing from → 130 → 135 → ……, it is possible to continue the fluctuation in the same adjustment direction, in which the bluish color is strengthened and the yellowish color is weakened visually.

  Thus, in principle, the yellow / blue variation operation is performed both by a method of increasing / decreasing the gradation values of the primary colors R and G simultaneously by the same amount or by a method of increasing / decreasing the gradation value of the primary color B. However, in practice, it is preferable to alternately and repeatedly execute the operation of simultaneously changing the gradation values of the primary colors R and G by the same amount and the operation of changing the gradation values of the primary color B. . For example, when the gradation values of the primary colors R and G are gradually increased by the same amount at the same time and one of them reaches the maximum gradation value (for example, R = 255), this time, the gradation value of the primary color B Perform an operation to gradually decrease. When the gradation value of the primary color B reaches the minimum gradation value (for example, B = 0), this time, the gradation values of the primary colors R and G are gradually decreased by the same amount at the same time. When one of them reaches the minimum value (for example, G = 0), the gradation value of the primary color B is gradually increased in the future. When the gradation value of the primary color B reaches the maximum gradation value (for example, B = 255), the gradation values of the primary colors R and G are gradually increased by the same amount at the same time. In this way, if the fluctuations of the primary colors R and G and the fluctuation of the primary color B are alternately performed, the operator alternately turns yellowish, bluish, yellowish, bluish, and becomes yellowish or bluish periodically. In addition, it is possible to present the test pattern T2 that changes, and to change the gradation value of each color in the entire range from the maximum gradation value to the minimum gradation value.

  Eventually, in this embodiment, the comparison result input means 430 indicates that the color of the reference body RE and the color of the test pattern T2 are most approximated when the gradation value changing means 440 is performing the red / green changing operation. And the yellow / blue indicating that the color of the reference body RE and the color of the test pattern T2 are closest to each other in a state where the gradation value changing means 440 performs the yellow / blue changing operation. Approximate signal is input from the operator, and when both the red / green approximate signal and the yellow / blue approximate signal are input, it is assumed that the comparison result indicating that the comparison target is matched is input. It will be handled.

  Of course, the same approach can be taken in the embodiment shown in the flowchart of FIG. That is, in step S21, predetermined initial values are set for the gradation values of the three primary colors RGB, and in step S23, the above-described red / green variation operation is performed instead of the green variation operation, and the click operation in step S24 is performed. The red / green approximate signal can be input. Similarly, in step S25, the yellow / blue variation operation described above is performed instead of the blue variation operation, and the yellow / blue approximate signal can be input by the click operation in step S26. Eventually, the gradation value changing means 440 starts the yellow / blue changing operation when the red / green approximate signal is input (step S24) in the state where the red / green changing operation is performed (step S23). When the yellow / blue approximate signal is input (step S26) in the state where the / blue variation operation is being performed (step S25), the red / green variation operation and the yellow / blue variation operation are started. Are repeatedly executed alternately and while the gradation value fluctuation amount and fluctuation range are gradually reduced. Further, the comparison result input means 430 indicates that the comparison object matches when the input of both the red / green approximate signal and the yellow / blue approximate signal is completed after the fluctuation amount reaches a predetermined specified value. The comparison result is handled as input.

  Note that there are some matters to be noted when performing the circulation fluctuation and the reciprocation fluctuation shown in FIG. 28 during the yellow / blue fluctuation operation. First, in the case of performing cyclic fluctuation, when the gradation value of at least one of the primary color R and the primary color G exceeds the maximum gradation value, the gradation value of the primary color R or the gradation value of the primary color G Or, the smaller one circulates to the minimum gradation value side, and processing is performed so that the difference between the two gradation values becomes constant. For example, in a state where a fluctuation range of 0 to 255 is set, (R = 200, G = 100) → (R = 205, G = 105) → (R = 210, G = 110) → (R = 215 , G = 115) →..., And gradually increasing (R = 255, G = 155), the gradation value of the primary color R exceeds the maximum gradation value. Therefore, the gradation value (G = 155) of the smaller primary color G is circulated to the minimum gradation value side, for example, G = 0 is set. The gradation value of the other primary color R may be set to R = 100 so that the difference from the gradation value of the primary color G is constant. By doing so, it is possible to change the circulation while always maintaining the difference between the gradation values of the primary colors R and G at 100. Similarly, when the gradation value of at least one of the primary color R and the primary color G falls below the minimum gradation value, the gradation value of the primary color R or the gradation value of the primary color G, whichever is greater May be circulated to the maximum gradation value side, and the difference between the two gradation values may be constant.

  In the case of performing reciprocal fluctuation, if the gradation value of at least one of the primary color R and the primary color G exceeds the maximum gradation value, the gradation value of the primary color R and the gradation value of the primary color G In both cases, a loopback process for switching to a changing operation for subtracting the changing amount may be performed. For example, in a state where a fluctuation range of 0 to 255 is set, (R = 200, G = 100) → (R = 205, G = 105) → (R = 210, G = 110) → (R = 215 , G = 115) →..., And gradually increasing (R = 255, G = 155), the gradation value of the primary color R exceeds the maximum gradation value. Therefore, this time, (R = 250, G = 150) → (R = 245, G = 145) → (R = 240, G = 140) →... What is necessary is just to switch to a variable operation. By doing so, it is possible to perform reciprocal fluctuations while always maintaining the difference between the gradation values of the primary colors R and G at 100. Similarly, when the gradation value of at least one of the primary color R and the primary color G falls below the minimum gradation value, both the gradation value of the primary color R and the gradation value of the primary color G vary. A loopback process for switching to a variable operation for adding the amount may be performed.

  As described above, according to the embodiment of the present invention, the monitor characteristic measuring apparatus 101 sets the chromaticity of the RGB primary colors according to the type of the monitor 207, and visually or using the measuring device 105, the RGB The gradation reproduction characteristics of the RGB primary colors are measured by an achromatic gradation instead of a single gradation, and the reference white color is measured under a predetermined lighting environment by visual observation or using the measuring device 105 to obtain a white chromaticity. Measurement is performed, and a monitor profile is created and held from data such as the chromaticity of the RGB primary color, the tone curve indicating the gradation reproduction characteristics of the RGB primary color, and the white chromaticity as the measurement results.

  As a result, according to the present invention, when a process in which additive color mixture is established is processed in a monitor in which additive color mixture is not established, the calculation accuracy of color / tone reproduction characteristics in the vicinity of an achromatic color is improved. On the other hand, the effect of improving accuracy cannot be expected for high saturation colors. However, humans are more sensitive to color differences near achromatic colors than high-saturated colors, and natural images contain more colors near achromatic colors than high-saturated colors. Therefore, it can be said that the improvement in the accuracy near the achromatic color is more effective than the improvement in the accuracy of the high saturation color. Therefore, it is possible to efficiently improve the color / tone reproduction characteristics of the monitor, and to perform highly accurate correction according to the display characteristics of each monitor.

  Note that the program for performing the processing shown in FIGS. 4, 5, 16, 30, 31, 32, etc. may be stored in a recording medium such as a CD-ROM and distributed. It is also possible to send and receive via.

  The preferred embodiments of the monitor profile creation system and the like according to the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to such examples. It will be apparent to those skilled in the art that various changes or modifications can be conceived within the scope of the technical idea disclosed in the present application, and these are naturally within the technical scope of the present invention. Understood.

The figure which shows schematic structure of the monitor profile creation system 100 which concerns on this Embodiment. Hardware configuration diagram of the monitor characteristic measuring apparatus 101 The figure which shows the data structure of the monitor profile creation system related file The flowchart which shows the process sequence of the monitor profile creation system 100 The flowchart which shows the process sequence of the monitor profile creation system 100 The figure which shows the selection screen 601 of a monitor kind The figure which shows the adjustment screen 602 of a gradation The figure which shows the white adjustment screen 603 Graph showing general tone reproduction characteristics of monitor It is a figure which shows the basic principle of the typical method which measures a gradation reproduction characteristic by visual observation, A figure (a) is a top view which shows the test pattern shown to an operator, A figure (b) is the 2nd in this test pattern. Partial enlarged view of the attribute area 20 The figure which shows the graph which shows the gradation reproduction characteristic calculated | required based on the measurement result using the test pattern shown in FIG. Graph showing the results of measuring the tone reproduction characteristics of each primary color for a general color monitor The top view which shows an example of the operation panel used when performing brightness variation operation and color variation operation based on an operator's operation input The top view which shows another example of the operation panel used when performing brightness variation operation and color variation operation based on an operator's operation input The top view which shows an example of the operation panel used when performing brightness variation operation and color variation operation automatically, and making an operator perform coincidence input operation The flowchart which shows an example of the process sequence which performs repeatedly the operation which matches brightness, and the operation which matches a color alternately. The graph for demonstrating embodiment which calculates | requires the approximate function curve which passes 5 points | pieces O, Q1, Q2, Q3, and P by calculation A graph for explaining a calculation method when an approximate function curve passing through five points O, Q1, Q2, Q3, and P becomes an S-shaped curve A plan view (FIG. (A)) showing a new test pattern capable of obtaining a more preferable measurement result, and an enlarged view of a reference pattern displayed in the second attribute area 60 in this test pattern (FIG. (B)) ) The top view which shows the example which formed the reference pattern of reference luminance 25% and 75% using the reference pattern which arranged the rectangular unit cell in the two-dimensional matrix form The top view which shows the example which comprised the area | region 70 of the same attribute by the circle | round | yen of the same radius r, and has arrange | positioned with the predetermined pitch on the two-dimensional plane A plan view for explaining the sensitivity of the visual system when a pair of objects (circular regions having the same attribute) 70 are arranged at a pitch Px. It is a graph which shows the sensitivity characteristic of a human visual system, a horizontal axis shows the spatial frequency (unit: cycle / deg) of an observation target object with a logarithmic scale, and a vertical axis discriminates the light-dark difference and color difference of an object. Indicates the relative sensitivity value of the human visual system. A table showing each optimum value extracted from the graph shown in FIG. Block diagram showing the basic configuration of monitor tone reproduction characteristics measurement processing Block diagram showing the configuration of white chromaticity measurement processing of a color monitor The top view which shows an example of the operation panel utilized for the measurement operation | work by the white chromaticity measurement process shown in FIG. The figure which shows the operation of the circulation fluctuation when changing the gradation value of the specific color, and the operation of the reciprocation fluctuation The top view which shows another example of the operation panel utilized for the measurement operation | work by the white chromaticity measurement process shown in FIG. 29 is a flowchart showing a measurement procedure using the operation panel shown in FIG. Flow chart showing the most practical measurement procedure in the white chromaticity measurement process The flowchart which shows the process sequence of the monitor profile creation system 100 using the measuring device 105. FIG. Diagram showing measurement results of gradation reproduction characteristics From the result of FIG. 33, a graph showing tone reproduction characteristics The figure which shows the color reproduction principle 700 of a liquid crystal monitor The figure which shows schematic structure of the monitor profile creation system 100 measured by visual observation

Explanation of symbols

100: Monitor profile creation system 101: Monitor characteristic measuring device (personal computer)
105 ......... Measurement device 201 ......... Control unit 202 ......... Storage device 207 ......... Monitor 210 ......... Tone value designation means 220 ......... Reference pattern generation means 230 ......... Pattern display device 240 ... ... gradation value changing means 250 ......... coincidence signal input means 251 ... ... brightness coincidence signal input means 252 ... ... color coincidence signal input means 260 ... ... characteristic calculation means
301 ......... RGB primary color chromaticity data 302 ......... Monitor profile 410 ......... Test pattern display means 420 ......... Tone value storage means 430 ......... Comparison result input means 440 ......... Tone value fluctuation means 450 ……… Measurement result output means RE ………… Reference body showing white as reference T1, T2 ……… Test pattern

Claims (8)

A system for creating a monitor profile comprising a terminal device connected to a color monitor having a function of displaying a color image using three primary colors RGB,
RGB primary color chromaticity setting means for setting chromaticity of RGB primary colors according to the type of the color monitor;
Gradation reproduction characteristic measuring means for measuring gradation reproduction characteristics of RGB primary colors based on display brightness and gradation value of the color monitor;
White chromaticity measuring means for measuring white chromaticity of the color monitor;
Monitor profile creation means for creating and holding a monitor profile from data such as chromaticity of the RGB primary color, gradation reproduction characteristics of the RGB primary color, and white chromaticity;
A monitor profile creation system comprising: 2. The monitor profile creation system according to claim 1, wherein the gradation reproduction characteristic measuring means measures the gradation reproduction characteristic visually or using a measuring instrument. The white chromaticity measuring means selects a reference white, measures the reference white under a predetermined illumination environment using visual inspection or a measuring instrument, and measures the white chromaticity. 1. The monitor profile creation system according to 1. 2. The monitor profile creation system according to claim 1, wherein a combination of chromaticities of RGB primary colors is held in advance for each type of color monitor. The gradation reproduction characteristic measuring means includes a brightness changing operation for changing the gradation value so that the brightness changes according to the type of the color monitor, and a color changing operation for changing the gradation value so that the color changes. The monitor profile creation system according to claim 1, wherein the gradation reproduction characteristic is adjusted. 2. The monitor profile creation system according to claim 1, wherein the type of the color monitor includes at least one of a CRT color display, a liquid crystal color display, a notebook personal computer display, and the like. A program that causes a computer to function as the monitor profile creation system according to any one of claims 1 to 6. A recording medium on which a program for causing a computer to function as the monitor profile creation system according to any one of claims 1 to 6 is recorded.

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