TWI360806B - Method for creating color correction table of digi - Google Patents

Description

1360806 _November 100 '21st shuttle replacement ^ VI, invention description: [Technical field of invention] [〇〇〇1] The present invention relates to a digital image device color correction table generation method and composite color measurement separation method . [Prior Art] [0002] With the increasing use of digital video devices, there is an increasing demand for the quality of display images of digital video devices. Generally, in the color theory of the three primary colors, 'any color is mixed by the three primary colors in a certain ratio, wherein the brightness of the color depends on the brightness of each single primary color and the chromaticity of the color depends on the mixing of the individual primary colors. proportion. In a digital image device that performs image display and image processing using three primary colors, the digital image device converts the video signal into an image display on the visual effect, indicating that the brightness and chromaticity of the color of the image display device are determined by the digital image device. In the strength of the video signal, the video signal is equally divided into two equal parts by 256, so that the digital video device displays a picture from black to white, and each part is called a gray level. The color displayed in each gray scale is mixed by the three primary colors in a certain proportion. "The current digital image device displays the brightness of the digital image device when only the screen corresponding to each single primary color signal is displayed in each gray scale. The chromaticity is measured and adjusted separately to achieve the purpose of improving the quality of the displayed picture. [0003] However, in the measurement process of brightness and chromaticity, the current digital image device separately measures the brightness and chromaticity of each face corresponding to each single primary color signal, and the measurement process is slow. It takes a long time to use the measurement method to generate a color correction table to adjust the brightness and chromaticity of the display screen of the digital image device. The time taken for the 096109263 Form No. 1010101 Page 4 / Total 24 Page 1003431408- 0 1360806 On November 21, 100, the shuttle replacement page was also longer, which is not conducive to the promotion and application on the production line. Moreover, when the chromaticity of the display screen of the digital image device is adjusted, each single primary color is separately adjusted, and the ratio of each single primary color of each gray level cannot be accurately adjusted, and the color matching of the display image of the digital image device is poor. The display is not good. SUMMARY OF THE INVENTION [0004] In view of the above, it is necessary to provide a digital image device color correction table generating method that can shorten measurement time and improve color matching. [0005] It is also necessary to provide a composite color measurement separation method. [0006] A method for generating a digital image device color correction table, comprising the steps of: step S1, turning off the color correction function set by the digital image device itself to be detected; and step S2, initializing the digital image device color correction table a generating system; step S3, measuring a base point of the color gamut that the digital image device can display; step S4, measuring the brightness and chrominance excitation value of the grayscale interval white surface of the digital image device; and step S5, calculating the digital image The luminance values of the three colors of the red, green, and blue colors corresponding to the gray scale interval of the gray scale interval displayed by the device are performed; in step S6, the luminance values of the red, green, and blue colors of the medium gray interval of step S5 are respectively interpolated to obtain Red, green, and blue three actual brightness characteristic curves; step S7, calculating three ideal brightness characteristic curves of red, green, and blue; step S8, searching for the gray level brightness on the ideal brightness characteristic curve on the actual brightness characteristic curve The closest point to the value and store the actual brightness characteristic

The value corresponding to the closest point of I; in step S9, the values obtained in step S8 are arranged in a descending order of the corresponding gray scales to generate a color correction table. Wherein, in step S4, the 0th, 4th, and 8th 096109263 in the 256-level gray scale are respectively measured. Form No. A0101 Page 5 / Total 24 Page 1003431408-0 1360806 __ 100 November '21 Day Nuclear Replacement Page - .. ...248, 252 grayscale white screen brightness, chrominance excitation value. [0007] A digital image device composite color measurement separation method, comprising the following steps

Step I: Step S1, measuring the base point of the color gamut that can be displayed by the digital image device • 'Step S2, measuring the brightness and chrominance excitation value of the composite color display by the digital image device; Step S3 'Calculating the digital display device to display the composite color Corresponding monochrome brightness value; step S4, using the Bezier interpolation calculation method, the monochrome brightness values of the medium gray interval of step S3 are respectively interpolated to obtain the actual brightness characteristic curve of the single color corresponding to the composite color; S5 'calculating the ideal brightness characteristic curve of the single color corresponding to the composite color; step S6, searching for the point closest to the gray level brightness value of the ideal brightness characteristic curve on the actual brightness characteristic curve, and storing the actual The value corresponding to the closest point on the brightness characteristic curve; in step S7, the values obtained in step S6 are arranged in order from the smallest to the largest gray level to generate a color correction table. [0008] Compared with the prior art, the method for generating a color correction table of the digital image device of the present invention uses the color analyzer to perform brightness and chrominance excitation values of the white screen of the gray scale interval displayed by the digital image device respectively. Measurement, and then calculate the brightness of each of the red, green and blue colors of each white picture, and then obtain the brightness of the red, green and blue colors of all the gray levels by interpolation method, and finally correct the actual according to the ideal gray level brightness. The gray scale brightness gives a color correction table. Since only the brightness of a few grayscale white pictures is measured, and other steps are calculated by the data acquisition analysis computer, the time for generating the color correction table by the color correction table generation method of the present invention is shortened, which is advantageous for each digital image device. Perform color correction separately to get the quality of the displayed image. Use this color correction table pair 096109263 Form No. A0101 Page 6 / Total 24 Page 1003431408-0 1360806 • t» [0009] [0010] [0012] [0013] 100 years. November 21st is replaced by positive When the Λ Λ 像 像 像 像 昼 昼 像 像 像 像 像 像 像 Λ Λ Λ Λ Λ Λ Λ Λ Λ Λ Λ Λ Λ Λ Λ Λ Λ Λ Λ Λ Λ Λ Λ Λ Λ Λ Λ Λ Λ Λ Λ Λ Λ Λ Λ The quality of the display screen is still available. [Embodiment] The method for generating a color correction table of a digital image device of the present invention needs to apply a system including a data acquisition and analysis computer, a video signal generation, a color analyzer, and a digital image device requiring measurement adjustment. The data acquisition and analysis computer includes a VGA (Video Graphics Array) graphics card and a plurality of scratchpads, and the video signal generator can be the VGA graphics card. The digital image device includes a memory. The color analyzer adopts a non-contact measurement design, which provides a luminance and chromaticity coordinate system χγζ, wherein coordinate values X, Υ, and Ζ respectively indicate red, green, and blue primary colors to display picture brightness and color for the digital image device. The incentive value of the degree. 'Xuan video signal generator is a standard video signal source. * A white screen is provided to the digital video device. The color analyzer directly obtains the excitation value of the display and the chromaticity of the current digital image device by extending the probe to the display surface of the digital image device, and then the color analyzer transmits the excitation value to the temporary storage of the data acquisition and analysis computer. The towel is processed by the data acquisition and analysis computer. Please refer to m ’ a flowchart of a method for generating a color correction table for a digital image device of the present invention. Step S1 ' strikes the color correction function. The digital image device starts to work 096109263 Form No. A0101 Page 7 / Total 24 Page 1003431408-0 [0014] [0014] 1360806 jl〇〇年ΐΐ^.21 A few days ago, the digital image device to be detected is closed by a software. The set color correction procedure. In step S2, the system is initialized. The video signal generator, the color analyzer, the remote data acquisition and analysis computer, and the digital image insertion are initialized. The video signal generator is arranged to generate a video signal composed of the maximum signals of the three primary colors of red, green and blue. The video signal causes the digital image to display a white picture with maximum brightness and chromaticity. The video signal is equally divided by the signal strength by 64 to cause the digital video device to display 〇, 1, 2, 62, 63 grayscale white pictures, respectively. The brightness and chromaticity of the 灰, 1, 2, 62, 62 grayscale white screen respectively correspond to the 0th, 4th, 8th, 248th, 252th grayscale white after the video signal is equally divided by the signal strength by 256. The brightness and chromaticity of the picture. [0015] Step S3, acquiring the brightness value of the digital image device. Please refer to FIG. 1 and FIG. 2, wherein FIG. 2 is a flow chart for obtaining display brightness and chromaticity in the method for generating a digital image device color correction table according to the present invention. When the digital image device displays G, Bu 2, 62, and 63 grayscale white screens respectively, the brightness and chromaticity of each of the three primary colors of red, green, and blue are obtained, and the process can be subdivided into the following steps: [0016 Step S3 measures the base point of the color gamut that the digital image device can display. The video signal generator generates three strongest single primary color signals, respectively, and the three strongest single primary color signals respectively cause the digital image device to display only the maximum intensity, chromaticity of red, green, and blue colors. When the strongest red signal, that is, the S-parameter image device, displays the red luminance chromaticity maximum, the X, Υ, and Ζ excitation values are measured by the color meal analyzer as Xr, Yr, and Zr, respectively. The same reason, 'the strongest green and blue signal', that is, the digital image device respectively shows 096109263

Form No. A0101 Page 8 / Total 24 W ' Ά 1003431408-0 1360806 100 years. On November 21, when the replacement page shows green, blue brightness, and maximum chromaticity, use the color analyzer to measure X and 分别 respectively. The Z excitation values are Xg, Yg, Zg, and Xb, Yb, and Zb, respectively. The excitation values Xr, Yr, Zr, Xg, Yg, Zg and Xb, Yb 'Zb are stored in a register of the data acquisition and analysis computer. [0017] Step S32, setting an i-th grayscale white screen. The video signal generator generates a video signal that causes the digital video device to display an i-th (i = 0, 1, 2, 62, 63) grayscale white picture. [0018] Step S33, measuring the grayscale white screen excitation value. When the digital image device displays the i-th gray scale white surface, the color analyzer is used to measure the X, Y, Z excitation values and store the excitation values in the temporary register of the data acquisition and analysis computer. Let the X, Y, and Z excitation values be Xi, Yi, and Zi, respectively. [0019] Step S34, calculating red, green and blue three color brightness values. The data acquisition and analysis computer calculates the brightness values of the red, green and blue colors when the digital image device displays the i-th gray scale white surface. The red, green, and blue colors are used to display the luminance coefficients of the i-th white screen luminance and chromaticity for the digital video device, respectively, K r 1 , K g 1, and 1 are represented by the following equation: ibi, the contribution The coefficients Kri, Kgi, Kbi can be [0020]

Ydi •. Mi 2

翁3⁄4.3⁄4 K:rKr-KS

[0021] When the digital image device displays the i-th gray scale white surface, the brightness of the red, green and blue colors respectively is Lri, Lgi, Lbi, then Lr i, Lgi 096109263 form number A0101 page 9 / total Page 24, 1003431408-0 1360806 November 21, 2010 □ The nuclear replacement page, Lb i can be expressed by the following formula: [0022] • Lri ~Xr Xg Xb -lx ~xf Lgi '- Yr Yg Yb Yi Lbi Zr Zg Zb_ Zi 歹玢 。. [0023] Step S35, storing the red, green and blue three color brightness values. The calculated luminance values Lr i, Lg i, Lb i of the red, green and blue colors are stored in a register of the data acquisition and analysis computer. [0024] Step S36, setting a next-level grayscale white screen. The video signal generator generates a video signal that causes the digital video device to display an i-th level 1 gray scale white surface. [0025] Step S37, it is determined whether the measurement ends. It is determined whether the total number of luminance values corresponding to red stored in the buffer of the video signal generator is greater than 64. If not, step S33 is performed; if yes, step S4 is performed. [0026] Step S4, interpolation calculation. The process of interpolation calculation is performed in the data acquisition and analysis computer, and the specific method is shown in FIG. Points P0, PI, P2, P3, P62, and P63 respectively indicate luminance values LrO, Lrl, Lr2, Lr62, and Lr63 corresponding to red when the digital video apparatus displays a 64-level grayscale white screen. A Bezier curve can be determined from three points of P0, PI and P2. On the Bezier curve, between the points P0 and P1, 15 points M1, M2, M15 of the gray-scale interval are taken. According to the same original 096109263 Form No. A0101 Page 10 / Total 24 Page 1003431408-0 1360806 « 1 100 years. November 21, according to the positive replacement page, PI, P2, P3 also determine a Bezier curve, in the shell On the Zil curve, between the points P1 and P2, 15 points M17, M31 of the gray-scale interval are also taken, and so on, and 15 points are inserted between any two adjacent points between P0 and P62. point. Points P61, P62, and P63 also determine a Bezier curve. On the Bezier curve, 15 points of the gray-scale interval are taken on both sides of the point P63, and a total of 1,024 points Mm are obtained (m = 0, 1, 2, 1, 022, 1 023). The 1,024 points form a curve, that is, the actual brightness characteristic curve corresponding to the red of the digital image device. According to the same principle, the actual brightness characteristic curves corresponding to the green and blue colors can be obtained. [0027] Step S5, obtaining a color correction table. Please refer to FIG. 1 and FIG. 4 together. FIG. 4 is a flowchart of obtaining a color correction table in the method for generating a color correction table of the digital image device of the present invention. The process of obtaining the color correction table is performed in the data acquisition and analysis computer, which can be subdivided into the following steps: [0028] Step S51, three ideal brightness characteristic curves of red, green and blue are acquired. The ideal brightness characteristic curve corresponding to red can be obtained by the following equation: [0029] Ln = (Linax - Lmin) (n/255) 'gamma + Lmin [0030] wherein Lmax indicates that the digital image device has the largest red signal, The maximum brightness value, Lmin is the brightness at 0th order, n(n = 0, 1, 2, 255) represents the order of any one of the 0 to 255 gray levels, and Ln represents the red nth level. The gamma is a constant, and the value is 2.2. When η sequentially takes a value between 0 and 255, let L_ values be L0, LI, L254, L255, respectively, then L0, L1, L254, L255 correspond to 256 points Qn respectively (n = 0, Bu 2 , 255), the curve of the 256 points is the ideal brightness characteristic corresponding to red 096109263 Form No. A0101 Page 11 / Total 24 Page 1003431408-0 [0031] 1360806 [0033] [0035] [0036] On November 21, 1100, the nuclear correction replaced the f curve. According to the same principle, an ideal brightness characteristic curve corresponding to two colors of green and blue can be obtained. In step S52, the number of gray levels is set to η. Let the number of gray scales to be corrected by red be η (η = 0, 1, 2, 254, 255). In step S53, the nth gray scale is corrected. Please refer to FIG. 5, which is a schematic diagram of a method for correcting gray scale brightness according to the present invention. Here, the solid line indicates an ideal luminance characteristic curve corresponding to red, and the broken line indicates an actual luminance characteristic curve corresponding to red. Qn (n = 0, 1, 2, 255) indicates the point at which the red magic η-level gray scale corresponds to the ideal luminance Ln on the ideal luminance characteristic curve, and Mm represents the first of the 1,024 points on the actual luminance characteristic curve. Ra point. According to the brightness value Ln of the Qn, a point Mm whose brightness value is closest to the ideal brightness Ln value is found in 1024 points on the actual brightness characteristic curve, and the value m corresponding to the Mm point is stored in the data acquisition and analysis computer. In the scratchpad. In step S54, the next level gray scale is set. Let the next gray level to be corrected be n+1 〇 step S55, and judge whether the correction is completed. It is judged whether or not the gray level number n + 1 is greater than 255. If not, step S53 is performed; if yes, step S56 〇 step S56 is executed to generate a color correction table. According to the order of the gray level η from 0 to 255, the values corresponding to m stored in the data acquisition and analysis computer register are sequentially arranged to obtain a color correction table corresponding to red. According to the same principle, the color correction table corresponding to the green and blue colors can be obtained. Step S6, the color correction table is burned. Red, green, 096109263 Form No. A0101 obtained in this step S56 Page 12 of 24 1003431408-0

[0037] The UOU0UO blue color corresponding to the color memory of the β-color ant is burned in the digital image device, compared with the prior art, the method for generating the color correction table of the digital image device of the present invention is used. The color splitter takes a picture of the brightness and chromaticity of the 64-level gray-white picture displayed on the digital image device, and then calculates the _ white picture in the 64-level gray-scale white picture by calculation. The brightness of the three colors of red, green and blue, and then the brightness of the three colors of red, green and blue in the gray level of 256 by interpolation method, and finally correcting the actual gray level brightness according to the ideal gray level brightness and paying the color correction table . Since only the brightness of the 6th-level gray-scale white picture is measured, and other steps are obtained by the data acquisition and analysis computer, the time for generating the color correction table by the color correction table generation method of the present invention is shortened' favoring each unit. The digital image device performs color correction separately to improve the quality of the displayed image. [0038] The present invention uses a color analyzer to measure the luminance and chrominance excitation values of a 64-level grayscale white picture, and can also measure only the luminance and chrominance excitation values of a 32-level or 128-level grayscale white picture. In step S4, the grayscale interval is taken on the Bezier curve, and the grayscale interval may be taken on the straight line determined by the two adjacent points, and is not limited to the above embodiment. The present invention uses a color analyzer to measure the red color. The white screen in which the green and blue primary colors are combined can also measure the composite color formed by other colors, and is not limited to the above embodiment. [0039] In the step S51 of the present invention, obtaining three ideal brightness characteristic curves of red, green and blue can also be obtained by the following formula: [0040] Kr255=Lr255/Ltotal [0041] Kg255 = Lg255/Ltotal 096109263 Form No. A0101 Page 13/Total 24 pages 1003431408-0 loo year li month. 21th nuclear replacement page · 1360806 [0042] Kb255 = Lb255 / Ltotal [0043] Ltotal = Lr255 + Lg255 + Lb255 = Lw255 [0044] where Ltotal represents the Yr obtained in step S31, The sum of Yg and Yb, Lr255, Lg255, and Lb255 are divided into another 'J is Yr, Yg in step S31,

Yb, Kr255, Kg255, and Kb255 are the ratios of the three colors corresponding to red, green, and blue in Lw255, respectively, and the ideal brightness corresponding to red in the nth grayscale white screen [0045] Lrn= Kr255xLwn ' [0046] Lwn represents the brightness of the nth grayscale white picture obtained in step S4. When η sequentially takes a value between 0 and 255, an ideal luminance characteristic curve corresponding to red is obtained. According to the same principle, the ideal brightness characteristic curve corresponding to the two colors of green and blue can be obtained. Compared with the prior art, the present invention uses the method to obtain an ideal brightness characteristic curve, thereby generating a color correction table, and analyzing each gray by using the color correction table to adjust the chromaticity of the digital image device. The ratio of each single primary color of the order is adjusted by adjusting the scale, thereby improving the color accuracy of the display image of the digital image device, thereby improving the quality of the display image. [0048] In summary, the present invention has indeed met the requirements of the invention, and the patent application is filed according to law. However, the above is only a preferred embodiment of the present invention, and the scope of the present invention is not limited to the above-described embodiments, and those skilled in the art will be able to make equivalent modifications or changes in accordance with the spirit of the present invention. It is covered by the following patent application. [Simple Description of the Drawings] Form No. 1010101 096109263 Page 14 of 24 1003431408-0 1360806 • November 2011 2l·Day Correction Replacement Page [0049] FIG. 1 is a generation of a color correction table for a digital image device of the present invention. Method flow chart. 2 is a flow chart showing the display brightness and chromaticity in the method for generating a digital image device color correction table according to the present invention. 3 is a schematic diagram of interpolation calculation in a method of generating a color correction table of a digital image device of the present invention. 4 is a flow chart showing a method of obtaining a color correction table in the method of generating a color correction table of the digital image device of the present invention. [0053] FIG. 5 is a schematic diagram of a method for correcting gray scale brightness according to the present invention. [Main component symbol description] [0054] None 096109263 Form number A0101 Page 15 of 24 1003431408-0

Claims (1)

1360806 ιοί) November 21st, 21st, the replacement page VII, the scope of application for patents: 1. A method for generating a color correction table for a digital image device, comprising the following steps: Step S1, closing the digital image device to be detected and setting itself a color correction function; step S2, initializing the generation system of the digital image device color correction table; step S3, measuring a base point of the color gamut that the digital image device can display; and step S4, measuring the grayscale display of the digital image device The luminance and chrominance excitation values of the white screen are separated; in step S5, the luminance values of the three colors of red, green and blue corresponding to the white planes of the grayscale interval displayed by the digital image device are calculated; in step S6, the medium grayscale is performed in step S5. The luminance values of the three colors of red, green and blue are respectively interpolated to obtain three actual brightness characteristic curves of red, green and blue; in step S7, three ideal brightness characteristic curves of red, green and blue are obtained; step S8, On the actual brightness characteristic curve, find the point closest to the grayscale brightness value on the ideal brightness characteristic curve, and store The value corresponding to the closest point on the actual brightness characteristic curve; Step S9, the values obtained in step S8 are arranged in the order of the corresponding gray scales from small to large to generate a color correction table, wherein the measurement is respectively performed in step S4. The 0th, 4th, 8th, ..., 248, 252 grayscale white screen brightness and chrominance excitation values in the 6th gray scale. 2. The method for generating a digital image device color correction table according to claim 1, wherein the digital image device in the step S3 is in the strongest red, green, and blue signals, and the X ' Υ ' Ζ excitation value Xr, Yr, Zr, 096109263 Form No. A0101 Page 16 / Total 24 Page 1003431408-0 1360806 • 9 • November 21st, 100th, the replacement page Xg, Yg, Zg and Xb, Yb, Zb, steps In the S4, when the digital image device displays the i-th grayscale white screen, the X, Y, and Z excitation values are Xi, Yi, and Zi, respectively, and the digital image device displays the i-th grayscale white screen in step S5, and the calculation is performed. The formulas of the brightness of the three primary colors of red, green and blue Lr i, Lg i, Lb i are: Zri ~Xr Xg Xb~ -l„x 'Xi Lgi "— Yr Yg -Yb Yi Ibi Zr Zg. Zb Zi Ύγ 13⁄4 The method for generating a digital image device color correction table according to claim 1, wherein the actual brightness characteristic curve is obtained by using a Bezier interpolation calculation method in step S6. 4 As described in claim 1 Digital image device color correction table generation method, wherein, step In S6, a linear interpolation calculation method is used to obtain an actual brightness characteristic curve. The method for generating a digital image device color correction table according to claim 3, wherein the three actual brightness characteristics of red, green and blue obtained in step S6 are obtained. Each of the curves is formed by connecting 1024 points. The method for generating a color correction table for a digital image device as described in claim 5, wherein the value range of the 1 024 points is 0 to 1023. For example, the method for generating a digital image device color correction table according to the first aspect of the patent application, wherein the formula for calculating the ideal brightness characteristic curve in step S7 is 096109263, form number A0101, page 17 of 24 pages 1003431408-0 1360806, 100 years November _21 nuclear replacement page: Ln = (Lmax - Lmin) (n / 255) - gamma + Lmin, Lmax represents the maximum brightness of the digital image device only shows one of the three primary colors of red, green and blue The value, Lmin is the brightness at the 0th order, n(n = 0, 1, 2, ..., 255) represents the order of any one of the 0 to 255 gray levels, and Ln represents the nth gray level of the color. correspond The brightness value, gamma is a constant, and the value is 2.2. 8. The method for generating a color correction table for a digital image device according to claim 2, wherein the formula for calculating the ideal brightness characteristic curve in step S7 is: Kr255=Lr255/Ltotal Kg255=Lg255/Ltotal Kb255=Lb255/ Ltotal Ltotal = Lr255+ Lg255+ Lb255 = Lw255 Lrn= Kr255xLwn where Ltotal represents the sum of Yr, Yg, Yb obtained in step S3, and Lr255, Lg255, Lb255 are steps In S31, Yr 'Yg, Yb, Kr255, Kg255, and Kb255 are the ratios of the three colors corresponding to red, green, and blue in Lw255, and Lrn is the ideal brightness corresponding to red (n = 0, 1, 2, ..., 255), Lwn The brightness of the nth grayscale white screen obtained in step S6 is indicated. 9. A digital image device composite color measurement separation method, comprising the following steps S1, measuring a base point of a color gamut that can be displayed by the digital image device; and step S2, measuring the brightness and chrominance excitation value of the composite color device by the digital image device. ; 096109263 Form No. Α0101 Page 18 of 24 1003431408-0 1360806 » . . . , November 21, 100 correction replacement page step S3, calculate the monochrome image brightness corresponding to the composite image display composite color; Step S4, using the Bezier interpolation calculation method, interpolating the monochrome luminance values of the medium grayscale interval in step S3 to obtain an actual luminance characteristic curve of the single color corresponding to the composite color; Step S5, calculating and obtaining the corresponding composite color The ideal brightness characteristic curve of the single color; step S6, searching for the closest point to the gray level brightness value on the ideal brightness characteristic curve on the actual brightness characteristic curve, and storing the closest point on the actual brightness characteristic curve Corresponding values; Step S7, the values obtained in step S6 are arranged according to the order of the corresponding gray scales from small to large. Into the color correction table. 10. The composite color measurement separation method of the digital image device according to claim 9, wherein the monochrome color corresponding to the composite color is red, green, and blue, and the red, green, and blue monochrome signals are measured in step S1. When respectively, the digital image device displays the X, Y, and Z excitation values of the single color as Xr, Yr, Zr, Xg, Yg, Zg, and Xb, Yb, and Zb, respectively, and the digital image device displays the composite color in step S2. The X, Y, and Z excitation values are respectively Xi, Yi, and Zi. When the digital image device displays the composite color in step S3, the formulas for calculating the luminances Lr i, Lgi, and Lbi of the three primary colors of red, green, and blue are: Lri ~ Xr Xg -lx 'Xi Lgi fr Yg Yb Yi ibi Zr kg· Zb, Zi · :·— 096109263 义单号ΑΟΓΟΙ • Page 19 / Total 24 pages 1003431408-0