JP2017158170A - Color correction device, display device and color correction method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To properly correct γ characteristics for the three primary colors and white, to properly make color corrections as to white, and to properly make color corrections for an arbitrary color, with small resources.SOLUTION: According to one-dimensional lookup tables R_LUT, G_LUT and B_LUT, corrections are made as to R, G and B, respectively. According to one-dimensional lookup tables W_LUT(R), W_LUT(G) and W_LUT(B), corrections are made as to W. Further, levels of contribution of gray-scale values obtained through the former corrections and gray-scale values obtained through the latter corrections to gray-scale values Rout, Gout and Bout after the corrections are changed according to a color represented by a set of gray-scale values Rin, Gin and Bin before the corrections. The closer to white the color is, the larger the contribution of a gray-scale value obtained through the latter corrections is.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a color correction device, a display device, and a color correction method.

  In a liquid crystal display device, additive color mixing is performed to produce various colors by mixing three primary colors such as red, green, and blue. Therefore, in the liquid crystal display device, gradation values indicating the three primary color amounts are input, and colors corresponding to the input three gradation values are displayed.

  However, if the displayed color does not change smoothly when all or some of the three input gradation values are gradually changed, the observer who observes the displayed color has an unnatural impression. receive. This problem is particularly noticeable for white gradations.

  Therefore, in order to smoothly change the displayed color when all or some of the three gradation values are gradually changed, the gradation value indicating the primary color amount of the input primary color and the display are displayed. Correction of the γ characteristic indicating the relationship with the brightness of the primary color component of the color to be performed is performed.

  The correction of the γ characteristic is often performed according to a lookup table. The look-up table defines tone conversion characteristics and includes a plurality of input tone values serving as indexes and output tone values corresponding to the plurality of input tone values. When the γ characteristic is corrected according to the lookup table, gradation conversion is performed on the gradation value before gradation conversion according to the lookup table. In gradation conversion, an output gradation value corresponding to an input gradation value that matches the gradation value before gradation conversion is specified, and the specified output gradation value is set as a gradation value after gradation conversion. The

  In the case where one look-up table common to all three primary colors is prepared and the gamma characteristic is corrected according to the prepared look-up table, three look-up tables are used according to one look-up table. The gradation conversion is performed on each gradation value before gradation conversion. In this case, since the ratio of the three gradation values after gradation conversion cannot be made different from the ratio of the three gradation values before gradation conversion, color correction cannot be performed.

  In order to be able to perform color correction, it is proposed that three look-up tables respectively corresponding to the three primary colors are prepared and the γ characteristic is corrected according to the prepared three look-up tables. Has been. In this case, since the ratio of the three gradation values after gradation conversion can be made different from the ratio of the three gradation values before gradation conversion, color correction can be performed for white. However, depending on the characteristics of the liquid crystal display device, color correction may not be appropriately performed for an arbitrary color.

  It has been proposed to perform color correction according to a three-dimensional look-up table so that any color can be corrected appropriately regardless of the characteristics of the liquid crystal display device. The three-dimensional lookup table includes a set of a plurality of input tone values serving as an index and a set of output tone values for each of the plurality of sets of input tone values. When color correction is performed according to the three-dimensional lookup table, gradation conversion is performed on three gradation values according to the three-dimensional lookup table. In tone conversion, a set of output tone values corresponding to a set of input tone values that match the set of tone values before tone conversion is specified, and the specified set of output tone values is a tone. A set of gradation values after conversion is made. The techniques described in Patent Documents 1 and 2 are examples.

International Publication No. 2009/101802 JP 2002-016939 A

  In a liquid crystal display device, a frame image must be displayed immediately after a signal representing the frame image is input. For this reason, signal processing including color correction must be performed in real time. Thus, when color correction is performed according to a three-dimensional lookup table, the three-dimensional lookup table is preferably incorporated into hardware.

However, in the color correction performed according to the conventional three-dimensional lookup table, when each of the three gradation values is expressed by an 8-bit bit string, all combinations of the three gradation values are combined. 256 ³ × 3 = 50,331,648 bits of correction data must be held in the 3D lookup table, and many resources are required to incorporate the 3D lookup table into the hardware. I need it. For this reason, it is impractical to incorporate a three-dimensional lookup table into hardware.

  In the three-dimensional lookup table, it is possible to reduce the required resources by increasing the lattice point interval and reducing the correction data. However, when the correction data is reduced by increasing the lattice point interval, the γ characteristic and the color may not be appropriately corrected between the lattice points.

  These problems also occur when color correction is performed in a device other than the liquid crystal display device.

  The present invention is made to solve these problems. The problem to be solved by the present invention is to correct the γ characteristic appropriately for each of the three primary colors and white, appropriately correct the color for white, and correct the color for any color with less resources. To do it properly.

  The present invention relates to a color correction apparatus and a color correction method. A color correction device may be incorporated in the display device.

  The first one-dimensional lookup table, the second one-dimensional lookup table, and the third one-dimensional lookup table define tone conversion characteristics for the first primary color, the second primary color, and the third primary color, respectively. To do.

  According to the first one-dimensional lookup table, the second one-dimensional lookup table, and the third one-dimensional lookup table, the first primary gradation value, the second primary gradation value, and the third one, respectively. Gradation conversion is performed on the primary gradation value. A first secondary gradation value, a second secondary gradation value, and a third secondary gradation value are obtained.

  The first primary gradation value, the second primary gradation value, and the third primary gradation value indicate the primary color amounts of the first primary color, the second primary color, and the third primary color, respectively. The first secondary gradation value, the second secondary gradation value, and the third secondary gradation value indicate the primary color amounts of the first primary color, the second primary color, and the third primary color, respectively.

  The fourth one-dimensional lookup table, the fifth one-dimensional lookup table, and the sixth one-dimensional lookup table define tone conversion characteristics for white.

  According to the fourth one-dimensional lookup table, the fifth one-dimensional lookup table, and the sixth one-dimensional lookup table, the first primary gradation value, the second primary gradation value, and the third one, respectively. Gradation conversion is performed on the primary gradation value. A fourth secondary tone value, a fifth secondary tone value, and a sixth secondary tone value are obtained.

  The fourth secondary gradation value, the fifth secondary gradation value, and the sixth secondary gradation value indicate the primary color amounts of the first primary color, the second primary color, and the third primary color, respectively.

  From the first primary gradation value, the second primary gradation value, and the third primary gradation value, the first of each of the first secondary gradation value and the fourth secondary gradation value. Is determined to be the first contribution, and the second third order of each of the second secondary gradation value and the fifth secondary gradation value is determined. The magnitude of the contribution to the tone value is determined as the magnitude of the second contribution, and each of the third secondary gradation value and the sixth secondary gradation value to the third tertiary gradation value is determined. The contribution magnitude is determined to be the third contribution magnitude.

  The first tertiary gradation value, the second tertiary gradation value, and the third gradation value indicate the primary color amounts of the first primary color, the second primary color, and the third primary color, respectively.

  The first 2 so that the magnitude of the contribution of each of the first secondary gradation value and the fourth secondary gradation value to the first tertiary gradation value becomes the magnitude of the first contribution. A first tertiary gradation value is derived from the secondary gradation value and the fourth secondary gradation value, and a second 3 of each of the second secondary gradation value and the fifth secondary gradation value is obtained. The second tertiary gradation value is derived from the second secondary gradation value and the fifth secondary gradation value so that the contribution to the next gradation value becomes the second contribution. And the third secondary gradation value and the sixth secondary gradation value are adjusted so that the contribution of the third secondary gradation value to the third tertiary gradation value becomes the third contribution magnitude. A third tertiary gradation value is derived from the secondary gradation value and the sixth secondary gradation value.

  According to the present invention, each of the three primary colors is corrected according to the one-dimensional lookup table, and white is corrected according to the one-dimensional lookup table. The application amount of the former and latter corrections is changed according to the color expressed by the set of gradation values before correction. For this reason, the γ characteristic is appropriately corrected for each of the three primary colors and white, and the color is appropriately corrected for white. In addition, color correction is appropriately performed for an arbitrary color.

  Further, according to the present invention, the γ characteristic and the color are corrected according to the one-dimensional lookup table, so that the γ characteristic and the color are corrected with few resources.

1 is a block diagram showing a liquid crystal display device of Embodiment 1. FIG. 6 is a diagram illustrating an example of gradation conversion in Embodiment 1. FIG. 1 is a block diagram illustrating a color correction apparatus according to a first embodiment. 6 is a block diagram illustrating a color correction apparatus according to Embodiment 2. FIG. 10 is a block diagram illustrating a color correction apparatus according to Embodiment 3. FIG.

1 Embodiment 1
1.1 Liquid Crystal Display Device FIG. 1 is a block diagram illustrating a liquid crystal display device according to a first embodiment.

  A liquid crystal display device 1000 illustrated in FIG. 1 includes an input connector 1022, a timing controller 1024, a gate driver integrated circuit (IC) 1026, a source driver IC 1028, and a liquid crystal panel 1030. The timing controller 1024 includes a signal processing unit 1042. The signal processing unit 1042 includes a color correction unit 1062. The liquid crystal panel 1030 includes a plurality of pixels 1082. The liquid crystal display device 1000 may include components other than these components.

  The input signal 1102 includes a signal including image data. The image data includes gradation values Rin, Gin, and Bin for each of the plurality of pixels 1082.

  The input signal 1102 is a digital electrical signal, is transmitted by wire, is input to the input connector 1022, and is input to the timing controller 1024 via the input connector 1022. The input signal 1102 may be replaced with an input signal transmitted wirelessly, or the input connector 1022 may be replaced with a receiver that receives the input signal transmitted wirelessly. The input signal 1102 may be replaced with an input signal that is an analog electrical signal, and the liquid crystal display device 1000 converts the input signal that is an analog electrical signal into a digital electrical signal to obtain gradation values Rin, Gin, and Bin A A / D converter may be provided.

  The signal processing unit 1042 outputs a signal 1122 that is used to control timing for driving each of the plurality of pixels 1082. The output signal 1122 is input to the gate driver IC 1026. Further, the signal processing unit 1042 processes a signal including input image data and outputs a signal 1124 used for controlling a color displayed on each of the plurality of pixels 1082. The output signal 1124 is input to the source driver IC 1028.

  The color correction unit 1062 performs color correction when the signal 1124 is generated. When color correction is performed, the gradation values Rin, Gin, and Bin before correction are input to the color correction unit 1062 for each of the plurality of pixels 1082, and the gradation values Rout, Gout, and Bout after correction are the colors. Output from the correction unit 1062.

  Based on the signal 1122, the gate driver IC 1026 outputs an ON / OFF signal 1142 for controlling ON / OFF of a thin film transistor (TFT) provided in each of the plurality of pixels 1082 to the TFT gate.

  Based on the signal 1124, the source driver IC 1028 outputs a color signal 1144 for controlling the color displayed on each of the plurality of pixels 1082 to the TFT source. The color signal 1144 reflects the corrected gradation values Rout, Gout and Bout constituting the RGB data.

  The gate driver IC 1026 and the source driver IC 1028 constitute a drive circuit that causes the pixel to display a color expressed by a set of corrected gradation values Rout, Gout, and Bout for each of the plurality of pixels 1082. The driver circuit may be replaced with a driver circuit having a configuration different from that of the driver circuit.

  The liquid crystal panel 1030 is a display panel. An image is displayed on the liquid crystal panel 1030 by displaying the color represented by the set of corrected gradation values Rout, Gout and Bout for each of the plurality of pixels 1082 on the pixel.

1.2 Tone Conversion FIG. 2 is a diagram illustrating an example of tone conversion in the first embodiment.

  A one-dimensional lookup table 1202 shown in FIG. 2 defines gradation conversion characteristics when gradation conversion from gradation values before gradation conversion to gradation conversion after gradation conversion is performed. , 159, 160, 161,..., 255, 256 input gradation values 1222, and corresponding to the 256 input gradation values 1,..., 164, 169, 172, respectively. ... 256 output gradation values 1224 of 255. Each of the input gradation values 1222 is represented by an 8-bit bit string. Each of the output gradation values 1224 is represented by an 8-bit bit string. 256 input gradation values 1222 may be replaced with a plurality of input gradation values each represented by a bit string of 7 bits or less or 9 bits or more. The 256 output gradation values 1224 may be replaced with a plurality of input gradation values each represented by a bit string of 7 bits or less or 9 bits or more.

  When gradation conversion is performed according to the one-dimensional lookup table 1202, an input gradation value that matches the gradation value before gradation conversion is selected from 256 input gradation values 1222, and the selected input level is selected. The output tone value corresponding to the tone value is made the tone value after tone conversion. Thereby, the gradation value before gradation conversion is converted into the gradation value after gradation conversion. For example, when the gradation value before gradation conversion is 159, 160, or 161, the gradation value after gradation conversion is 164, 169, or 172, respectively.

1.3 Color Correction Device FIG. 3 is a block diagram illustrating the color correction device according to the first embodiment.

  A color correction device 1290 shown in FIG. 3 is incorporated in the liquid crystal display device 1000 to become a color correction unit 1062, which is a primary color correction unit 1302, a white correction unit 1304, a coefficient calculation unit 1306, and a gradation value calculation unit 1308. Is provided. The primary color correction unit 1302 includes a primary color gradation conversion unit 1322. The white correction unit 1304 includes a white gradation conversion unit 1342. The color correction device 1290 may include components other than these components.

  The color correction device 1290 may be incorporated in a liquid crystal display device having a configuration different from that of the liquid crystal display device 1000, a display device other than the liquid crystal display device, a device other than the display device, or the like.

  The input signal 1102 includes primary gradation values Rin, Gin, and Bin indicating the primary colors of red (R), green (G), and blue (B), which are the three primary colors, respectively. The primary gradation values Rin, Gin, and Bin are gradation values before correction, and are input to the primary color correction unit 1302, the white correction unit 1304, and the coefficient calculation unit 1306, respectively. R, G, and B may be replaced with three primary colors other than R, G, and B.

  The primary color gradation conversion unit 1322 defines gradation conversion characteristics relating to R, G, and B, which are sets of one-dimensional lookup tables for correcting primary gradation values Rin, Gin, and Bin, respectively. The one-dimensional lookup tables R_LUT, G_LUT, and B_LUT for primary colors are held. The primary color one-dimensional look-up tables R_LUT, G_LUT, and B_LUT are for correcting the γ characteristics of R, G, and B, respectively, and are preferably implemented by hardware.

  The gradation conversion unit 1322 for primary colors obtains a gradation value R′r after gradation conversion by performing gradation conversion on the primary gradation value Rin according to the one-dimensional lookup table R_LUT. A gradation value G′g after gradation conversion is obtained by performing gradation conversion on the primary gradation value Gin according to the lookup table G_LUT, and the primary gradation value Bin according to the one-dimensional lookup table B_LUT. Is subjected to gradation conversion to obtain a gradation value B′b after gradation conversion. The tone values R′r, G′g, and B′b after tone conversion output from the tone conversion unit 1322 for primary colors are directly output from the correction unit 1302 for primary colors. becomes' r, G'g and B'b. Thus, the primary color correction unit 1302 obtains secondary gradation values R′r, G′g, and B′b. Secondary gradation values R′r, G′g, and B′b indicate the primary color amounts of R, G, and B, respectively.

  The gradation conversion unit 1342 for white is a one-dimensional definition that defines gradation conversion characteristics relating to white (W), which is a set of one-dimensional lookup tables for correcting the primary gradation values Rin, Gin, and Bin. The lookup tables W_LUT (R), W_LUT (G), and W_LUT (B) are held. Since W is a mixed color of R, G, and B, the gradation conversion characteristics relating to W are one-dimensional lookup tables W_LUT (R), W_LUT (G), and W_LUT that define the gradation conversion characteristics relating to R, G, and B, respectively. Defined by pair (B). The one-dimensional lookup tables W_LUT (R), W_LUT (G), and W_LUT (B) are for correcting the γ characteristic and color of W, and are preferably implemented by hardware.

  The gradation conversion unit 1342 for white obtains a gradation value R′w after gradation conversion by performing gradation conversion on the primary gradation value Rin according to the one-dimensional lookup table W_LUT (R). The gradation value G′w after gradation conversion is obtained by performing gradation conversion on the primary gradation value Gin according to the one-dimensional lookup table W_LUT (G), and the one-dimensional lookup table W_LUT (B ), The gradation value B′w after gradation conversion is obtained by performing gradation conversion on the primary gradation value Bin. The tone values R′w, G′w, and B′w after tone conversion output from the white tone conversion unit 1342 are used as they are as the secondary tone value R output from the white correction unit 1304. becomes' w, G'w and B'w. Accordingly, the white correction unit 1304 obtains secondary gradation values R′w, G′w, and B′w. Secondary gradation values R′w, G′w, and B′w indicate primary color amounts of R, G, and B, respectively.

  The coefficient calculation unit 1306 calculates weight coefficients K_R, K_G, K_B, K_W (R), K_W (G), and K_W (B) from the primary gradation values Rin, Gin, and Bin. The weighting factors K_R, K_G, K_B, K_W (R), K_W (G) and K_W (B) are the one-dimensional lookup tables R_LUT, G_LUT, B_LUT, W_LUT (R), W_LUT (G) and W_LUT (B), respectively. Corresponding to Each of the weight coefficients K_R, K_G, K_B, K_W (R), K_W (G) and K_W (B) is a gradation after gradation conversion obtained by gradation conversion performed according to the corresponding one-dimensional lookup table. Indicates the weight of the value. Therefore, the weight coefficients K_R, K_G, K_B, K_W (R), K_W (G) and K_W (B) are respectively the secondary gradation values R′r, G′g, B′b, R′w, G ′. Indicates the weight of w and B'w.

  The gradation value calculation unit 1308 is a weighted sum K_R * R′r + K_W (R) * R′w obtained by multiplying the secondary gradation values R′r and R′w by weighting coefficients K_R and K_W (R), respectively. Is set to the third gradation value Rout, and the weighted sum K_G * G′g + K_W (G) * G ′ is obtained by multiplying the second gradation values G′g and G′w by the weight coefficients K_G and K_W (G), respectively. The weighted sum K_B * B′b + K_W (B) * B in which w is set to the tertiary gradation value Gout and the weighting factors K_B and K_W (B) are multiplied by the secondary gradation values B′b and B′w, respectively. 'w is set to the third gradation value Bout. The tertiary gradation values Rout, Gout, and Bout included in the output signal 1362 are corrected gradation values, and indicate the primary color amounts of R, G, and B, respectively.

  As the weighting coefficient K_R decreases, the contribution of the secondary gradation value R'r to the tertiary gradation value Rout decreases, and as the weighting coefficient K_R increases, the secondary gradation value R'r increases to the tertiary gradation value Rout. The contribution of the secondary gradation value R'w to the tertiary gradation value Rout decreases as the weighting coefficient K_W (R) decreases, and the secondary gradation increases as the weighting coefficient K_W (R) increases. The contribution of the value R′w to the tertiary gradation value Rout increases. For this reason, the weighting factors K_R and K_W (R) express the magnitude of the contribution of the secondary gradation values R′r and R′w to the tertiary gradation value Rout, respectively.

  Similarly, the weighting factors K_G and K_W (G) express the magnitude of the contribution of the secondary gradation values G′g and G′w to the tertiary gradation value Gout, respectively, and weighting factors K_B and K_W (B ) Expresses the magnitude of the contribution of the secondary gradation values B′b and B′w to the tertiary gradation value Bout, respectively.

  Therefore, the coefficient calculation unit 1306 expresses the magnitude of the contribution of the secondary gradation values R′r and R′w to the tertiary gradation value Rout by the weighting coefficients K_R and K_W (R). And determining the magnitude of contribution of each of the secondary gradation values G′g and G′w to the tertiary gradation value Gout to be expressed by weighting factors K_G and K_W (G). A determination unit is configured to determine the magnitude of the contribution of each of the gradation values B′b and B′w to the tertiary gradation value Bout to be expressed by the weighting factors K_B and K_W (B).

  Also, the gradation value calculation unit 1308 represents the magnitude of the contribution of the secondary gradation values R′r and R′w to the tertiary gradation value Rout by weighting factors K_R and K_W (R). The tertiary gradation value Rout is derived from the secondary gradation values R′r and R′w so as to be the same, and the secondary gradation values G′g and G′w are respectively obtained as the tertiary gradation values Gout. Deriving the tertiary gradation value Gout from the secondary gradation values G′g and G′w so that the magnitude of the contribution is expressed by the weighting factors K_G and K_W (G). The secondary gradation values B′b and B′b and B′w so that the magnitude of the contribution of each of the values B′b and B′w to the tertiary gradation value Bout is expressed by the weight coefficients K_B and K_W (B). A deriving unit for deriving the tertiary gradation value Bout from B′w is configured.

  When the weighting factors K_R, K_G, K_B, K_W (R), K_W (G) and K_W (B) are calculated, the color represented by the set of primary gradation values Rin, Gin and Bin to W An index Kw indicating the proximity is calculated by the equation (1).

  Kw = 1- (RGBin_MAX-RGBin_MIN) / RGBin_MAX (1)

  The maximum value RGBin_MAX is the maximum value of the primary gradation values Rin, Gin, and Bin, and is calculated by Expression (2).

  RGBin_MAX = MAX (Rin, Gin, Bin) (2)

  The minimum value RGBin_MIN is the minimum value of the primary gradation values Rin, Gin, and Bin, and is calculated by Expression (3).

  RGBin_MIN = MIN (Rin, Gin, Bin) (3)

  The index Kw is 1 when the color expressed by the combination of the primary gradation values Rin, Gin and Bin is W, so Rin = Gin = Bin, so that the color is R, G or B. In some cases, two of the primary gradation values Rin, Gin, and Bin are 0, so that they become 0 and become larger as the color becomes closer to white. Therefore, the index Kw is a factor indicating the weight of W, and the index 1-Kw obtained by subtracting the index Kw from 1 is a factor indicating the sum of the R weight, the G weight, and the B weight.

  In addition, an index Kr indicating the proximity of the color represented by the primary gradation values Rin, Gin, and Bin to R is calculated by the equation (4), and the index Kg indicating the proximity of the color to G is expressed by the equation The index Kb calculated by (5) and indicating the closeness of the color to B is calculated by the equation (6).

Kr = (1-Kw) * Rin / (Rin + Gin + Bin) (4)
Kg = (1-Kw) * Gin / (Rin + Gin + Bin) (5)
Kb = (1-Kw) * Bin / (Rin + Gin + Bin) (6)

  The index 1-Kw is a factor indicating the sum of R weight, G weight, and B weight, and Rin / (Rin + Gin + Bin), Gin / (Rin + Gin + Bin) and Bin / (Rin + The ratio of (Gin + Bin) indicates the ratio of the R weight, the G weight, and the B weight. Therefore, according to equations (4), (5), and (6), the sum of the R weight, G weight, and B weight is apportioned to each primary color of R, G, and B according to the weight of each primary color. The

  Further, the weighting factors K_W (R), K_W (G), K_W (B), K_R, K_G and K_B are expressed by equations (7), (8), (9), (10), (11) and (12), respectively. ).

K_W (R) = Kw / (Kr + Kw) (7)
K_W (G) = Kw / (Kg + Kw) (8)
K_W (B) = Kw / (Kb + Kw) (9)
K_R = 1-K_W (R) (10)
K_G = 1-K_W (G) (11)
K_B = 1-K_W (B) (12)

  The index Kr is a factor indicating the weight of R, and the index Kw is a factor indicating the weight of W. Therefore, the weighting coefficient K_W (R), which is the ratio of the index Kw to the sum of the indices Kr and Kw, specifies the ratio to which correction for W that is most affected by the characteristics of the liquid crystal display device 1000 should be applied. Similarly, each of the weighting factors K_W (G) and K_W (B) designates a ratio at which correction for W that is most affected by the characteristics of the liquid crystal display device 1000 should be applied.

  Equations (1) to (12) are examples, and weighting factors K_W (R), K_W (G), K_W (B), K_R, K_G, and K_B are different from equations (1) to (12). It may be calculated by an equation.

  Each of the weight coefficients K_W (R), K_W (G), K_W (B), K_R, K_G, and K_B takes a value of 0 or more and 1 or less. Also, the sum of the weight coefficient K_R and the weight coefficient K_W (R) is 1, the sum of the weight coefficient K_G and the weight coefficient K_W (G) is 1, and the weight coefficient K_B and the weight coefficient K_W (B) The sum is 1. Thereby, the tertiary gradation values Rout, Gout and Bout are obtained by a simple weighted sum.

  According to the weighting factors K_W (R), K_W (G), K_W (B), K_R, K_G and K_B, the color expressed by the set of primary gradation values Rin, Gin and Bin is close to white, and the index Kw The larger the is, the smaller the contribution of the secondary gradation value R′r to the tertiary gradation value Rout, and the greater the contribution of the secondary gradation value R′w to the tertiary gradation value Rout. The contribution of the gradation value G′g to the tertiary gradation value Gout is reduced, and the contribution of the secondary gradation value G′w to the tertiary gradation value Gout is increased, and the secondary gradation value B′b. The contribution of the secondary gradation value B'w to the tertiary gradation value Bout increases and the contribution of the secondary gradation value B'w to the tertiary gradation value Bout increases.

  A coefficient indicating the magnitude of the contribution of the secondary gradation values R′r and R′w to the tertiary gradation value Rout, and the tertiary gradations of the secondary gradation values G′g and G′w. The coefficient indicating the magnitude of the contribution to the value Gout and the coefficient indicating the magnitude of the contribution of the secondary gradation values B′b and B′w to the tertiary gradation value Bout are the tertiary gradation values. When the calculation formula for deriving Rout, Gout and Bout is replaced with another calculation formula, it is replaced with a coefficient corresponding to the other calculation formula.

  According to the first embodiment, the γ characteristics are corrected for R, G, and B according to the one-dimensional lookup tables R_LUT, G_LUT, and B_LUT, respectively, and the one-dimensional lookup tables W_LUT (R), W_LUT (G) And according to W_LUT (B), the γ characteristic and the color are corrected for W. In addition, the gradation values R′r, G′g and B ′ obtained by the former correction and the gradation values R′w, G′w and B′w obtained by the latter correction are corrected. The magnitude of the contribution to the values Rout, Gout and Bout is changed according to the color expressed by the set of gradation values Rin, Gin and Bin before correction. For this reason, the γ characteristic is appropriately corrected for each of R, G, B, and W, and the color is appropriately corrected for W. In addition, color correction is appropriately performed for an arbitrary color. Therefore, in the liquid crystal display device 1000 in which the color correction device 1290 is incorporated, color correction according to the characteristics of the liquid crystal panel 1030 is performed for an arbitrary color.

  In addition, according to the first embodiment, the γ characteristics and color correction are performed according to the one-dimensional lookup tables R_LUT, G_LUT, B_LUT, W_LUT (R), W_LUT (G), and W_LUT (B), so that there are few resources The γ characteristic and the color are corrected.

2 Embodiment 2
The second embodiment relates to a color correction apparatus that replaces the color correction apparatus according to the first embodiment.

  In the color correction apparatus of the first embodiment, each primary color is corrected according to one one-dimensional lookup table. However, in the color correction apparatus of the second embodiment, each primary color has three one-dimensional lookups. It is corrected according to the table. The purpose is to improve the accuracy of color correction for each primary color.

  FIG. 4 is a block diagram illustrating the color correction apparatus according to the second embodiment.

  The color correction apparatus 2000 shown in FIG. 4 includes a primary color correction unit 2022, a white correction unit 2024, a coefficient calculation unit 2026, and a gradation value calculation unit 2028. The primary color correction unit 2022 includes a primary color gradation conversion unit 2042 and a calculation unit 2044. The white correction unit 2024 includes a white gradation conversion unit 2062. The white correction unit 2024, the coefficient calculation unit 2026, the gradation value calculation unit 2028, and the white gradation conversion unit 2062 provided in the color correction device 2000 according to the second embodiment are the same as the color correction device according to the first embodiment. This is the same as the white correction unit 1304, the coefficient calculation unit 1306, the gradation value calculation unit 1308, and the white gradation conversion unit 1342 provided in 1290. Therefore, in the following, only the primary color correction unit 2022, the primary color gradation conversion unit 2042, and the calculation unit 2044 will be described.

  The primary color gradation conversion unit 2042 is a one-dimensional lookup table R_LUT (R), R_LUT (G) and R_LUT (B) each defining a gradation conversion characteristic for R, each of which has a gradation conversion characteristic for G. One-dimensional lookup tables G_LUT (R), G_LUT (G) and G_LUT (B) to be defined, and one-dimensional lookup tables B_LUT (R), B_LUT (G) and B_LUT, each of which defines gradation conversion characteristics for B Hold (B). The primary color one-dimensional lookup tables R_LUT (R), R_LUT (G) and R_LUT (B) are for correcting the outputs of R, G and B with respect to the primary gradation value Rin, respectively. Implemented in hardware. The primary color one-dimensional lookup tables G_LUT (R), G_LUT (G) and G_LUT (B) are for correcting the outputs of R, G and B with respect to the primary gradation value Gin, respectively. Implemented in hardware. The primary color one-dimensional lookup tables B_LUT (R), B_LUT (G), and B_LUT (B) are for correcting the output of R, G, and B with respect to the primary gradation value Bin, respectively. Implemented in hardware.

  The primary color gradation conversion unit 2042 performs gradation conversion on the primary gradation value Rin according to the one-dimensional lookup tables R_LUT (R), R_LUT (G), and R_LUT (B), respectively. The converted gradation values R'r (R), R'r (G) and R'r (B) are obtained according to the one-dimensional lookup tables G_LUT (R), G_LUT (G) and G_LUT (B). By performing gradation conversion on the primary gradation value Gin, the gradation values G′g (R), G′g (G) and G′g (B) after gradation conversion are obtained, respectively. The gradation value B′b (R) after gradation conversion by performing gradation conversion on the primary gradation value Bin according to the lookup tables B_LUT (R), B_LUT (G) and B_LUT (B) , B'b (G) and B'b (B) are obtained. Each of the gradation values R′r (R), G′g (R) and B′b (R) after gradation conversion indicates the primary color amount of R. Each of the gradation values R′r (G), G′g (G), and B′b (G) after gradation conversion indicates the primary color amount of G. Each of the gradation values R′r (B), G′g (B), and B′b (B) after gradation conversion indicates the primary color amount of B.

  The arithmetic unit 2044 adds the gradation values R′r (R), G′g (R), and B′b (R) after gradation conversion to add the secondary gradation value R′r = R′r. (R) + G'g (R) + B'b (R) is obtained, and the gradation values R'r (G), G'g (G) and B'b (G) after gradation conversion are added. By combining them, the secondary gradation value G′g = R′r (G) + G′g (G) + B′b (G) is obtained, and the gradation value R′r (B), By adding G′g (B) and B′b (B), a secondary gradation value B′b = R′r (B) + G′g (B) + B′b (B) is obtained. The gradation values R′r, G′g, and B′b after gradation conversion are output from the primary color correction unit 2022.

  According to the second embodiment, as in the first embodiment, the correction of the γ characteristic is appropriately performed for each of R, G, B, and W, the color correction is appropriately performed for W, and any color is selected. The color correction is appropriately performed. When the color correction device 2000 is incorporated in the liquid crystal display device 1000 instead of the color correction device 1290, color correction according to the characteristics of the liquid crystal panel 1030 is performed for an arbitrary color.

  Further, according to the second embodiment, as in the first embodiment, the γ characteristic and the color are corrected with less resources.

  In addition, according to the second embodiment, the accuracy of color correction for each primary color is improved.

  The third embodiment relates to a color correction device that replaces the color correction device of the first embodiment.

  In the color correction apparatus according to the first embodiment, the weight coefficients K_R, K_G, K_B, and K_W (1) corresponding to the one-dimensional lookup tables R_LUT, G_LUT, B_LUT, W_LUT (R), W_LUT (G), and W_LUT (B), respectively. R), K_W (G) and K_W (B) are calculated and corrected according to the six one-dimensional lookup tables. In the color correction apparatus according to the third embodiment, the one-dimensional lookup table R_LUT , G_LUT and B_LUT, one common weight coefficient K_RGB is calculated, and a common weight coefficient K_W corresponding to the one-dimensional lookup tables LUT (R), W_LUT (G) and W_LUT (B) is calculated, and 6 Correction is performed according to the one-dimensional lookup tables. The purpose is to reduce the amount of calculation required to calculate the weighting factor.

  FIG. 5 is a block diagram illustrating a color correction apparatus according to the third embodiment.

  A color correction device 3000 shown in FIG. 5 is incorporated in the liquid crystal display device 1000 to become a color correction unit 1062, a primary color correction unit 3022, a white correction unit 3024, a coefficient calculation unit 3026, and a gradation value calculation unit 3028. Is provided. The primary color correction unit 3022 includes a primary color gradation conversion unit 3042. The white correction unit 3024 includes a white gradation conversion unit 3062. The color correction device 3000 may include components other than these components. The primary color correction unit 3022, the white correction unit 3024, the primary color gradation conversion unit 3042, and the white gradation conversion unit 3062 provided in the color correction apparatus 3000 according to the third exemplary embodiment are respectively described in the first exemplary embodiment. This is the same as the primary color correction unit 1302, the white correction unit 1304, the primary color gradation conversion unit 1322, and the white gradation conversion unit 1342 provided in the color correction apparatus 1000. Therefore, hereinafter, the coefficient calculation unit 3026 and the gradation value calculation unit 3028 will be described exclusively.

  The color correction device 3000 may be incorporated in a liquid crystal display device having a configuration different from that of the liquid crystal display device 1000, a display device other than the liquid crystal display device, a device other than the display device, or the like.

  The coefficient calculation unit 3026 calculates weight coefficients K_RGB and K_W from the primary gradation values Rin, Gin, and Bin. The weight coefficient K_RGB corresponds to the one-dimensional lookup tables R_LUT, G_LUT, and B_LUT. The weight coefficient K_W corresponds to W_LUT (R), W_LUT (G), and W_LUT (B). The weighting coefficients K_RGB and K_W indicate the weights of gradation values after gradation conversion obtained by gradation conversion performed according to the corresponding one-dimensional lookup table.

  The gradation value calculation unit 3028 uses the weighted sum K_RGB * R′r + K_W * R′w obtained by multiplying the weighting coefficients K_RGB and K_W by the secondary gradation values R′r and R′w, respectively, as the tertiary gradation value. Rout, and the weighted sum K_G * G′g + K_W (G) * G′w obtained by multiplying the weighting factors K_RGB and K_W by the secondary gradation values G′g and G′w, respectively, becomes the tertiary gradation value Gout. The weighted sum K_B * B′b + K_W (B) * B′w obtained by multiplying the secondary gradation values B′b and B′w by the weight coefficients K_RGB and K_W, respectively, is set as the tertiary gradation value Bout. The tertiary gradation values Rout, Gout, and Bout included in the output signal 1362 are corrected gradation values, and indicate the primary color amounts of R, G, and B, respectively.

  The smaller the weighting coefficient K_RGB, the smaller the contribution of the secondary gradation value R'r to the tertiary gradation value Rout. The larger the weighting coefficient K_RGB, the more the secondary gradation value R'r becomes the tertiary gradation value Rout. The contribution of the secondary gradation value R′w to the tertiary gradation value Rout decreases as the weighting coefficient K_W decreases, and the secondary gradation value R′w of 3 increases as the weighting coefficient K_W increases. The contribution to the next gradation value Rout increases. For this reason, the weighting factors K_RGB and K_W express the magnitude of the contribution of the secondary gradation values R′r and R′w to the tertiary gradation value Rout, respectively.

  Similarly, the weighting factors K_RGB and K_W express the magnitude of the contribution of the secondary gradation values G′g and G′w to the tertiary gradation value Gout, respectively, and the secondary gradation values B′b and The magnitude of the contribution of B'w to the tertiary gradation value Bout is expressed.

  Therefore, the coefficient calculation unit 3026 determines the magnitude of the contribution of the secondary gradation values R′r and R′w to the tertiary gradation value Rout to be expressed by the weighting coefficients K_RGB and K_W, The magnitude of contribution of each of the secondary gradation values G′g and G′w to the tertiary gradation value Gout is determined to be expressed by weighting factors K_RGB and K_W, and the secondary gradation value B′b And a determination unit that determines the magnitude of contribution of each of B′w to the tertiary gradation value Bout to be expressed by the weight coefficients K_RGB and K_W.

  In addition, the gradation value calculation unit 3028 represents the magnitude of the contribution of the secondary gradation values R′r and R′w to the tertiary gradation value Rout by the weighting coefficients K_RGB and K_W. Thus, the third gradation value Rout is derived from the second gradation values R′r and R′w, and the contribution of the second gradation values G′g and G′w to the third gradation value Gout is calculated. A tertiary gradation value Gout is derived from the secondary gradation values G′g and G′w so that the magnitude is expressed by the weight coefficients K_RGB and K_W, and the secondary gradation values B′b and B ′ are derived. The secondary gradation values B'b and B'w to the tertiary gradation values so that the magnitude of the contribution of each of 'w to the tertiary gradation values Bout is expressed by the weighting factors K_RGB and K_W. A deriving unit for deriving Bout is configured.

  When the weighting coefficients K_RGB and K_W are calculated, an index K_W indicating the closeness to W of the color expressed by the set of primary gradation values Rin, Gin, and Bin is calculated by Expression (13).

  Kw = (RGBin_MED + RGBin_MIN) / (RGBin_MAX * 2) (13)

  The median value RGBin_MED is the median value of the primary gradation values Rin, Gin, and Bin, and is calculated by Expression (14).

  RGBin_MED = MED (Rin, Gin, Bin) (14)

  The index K_W is 1 when the color expressed by the set of primary gradation values Rin, Gin, and Bin is W, so Rin = Gin = Bin, so that the color is R, G, or B. In some cases, two of the primary gradation values Rin, Gin, and Bin are 0, so that they become 0 and become larger as the color becomes closer to white. For this reason, the index K_W is a factor indicating the weight of W.

  Also, an index K_RGB indicating the proximity of the color represented by the set of primary gradation values Rin, Gin, and Bin to a single color is calculated by Expression (15).

K_RGB = 1-K_W (15)
The weight coefficient K_RGB is an index obtained by subtracting the index K_W from 1 and is a factor indicating the sum of the R weight, the G weight, and the B weight.

  Expressions (13) to (15) are examples, and the weighting factors K_W and K_RGB may be calculated by expressions different from Expressions (13) to (15). For example, the weighting factors K_W and K_RGB may be calculated by equations (16) and (17).

K_W = 1- (RGBin_MAX-RGBin_MIN) / RGBin_MAX (16)
K_RGB = 1-K_W (17)

  According to the third embodiment, as in the first embodiment, the correction of the γ characteristic is appropriately performed for each of R, G, B, and W, the color correction is appropriately performed for W, and any color is selected. The color correction is appropriately performed.

  Further, according to the third embodiment, the γ characteristic and the color are corrected with fewer resources than in the third embodiment.

  It should be noted that the present invention can be freely combined with each other within the scope of the invention, and each embodiment can be appropriately modified or omitted.

  In the first to third embodiments, a liquid crystal display device is cited as an example of a display device including the color correction device of the present invention, and the embodiment has been described. However, the color correction in the present invention does not need to be performed in a specific display device, and may be performed in various display devices such as an organic electroluminescence (EL) display device and a micro electro mechanical system (MEMS) display.

  1000 liquid crystal display device, 1062 color correction unit, 1290, 2000, 3000 color correction device, 1302, 2022, 3022 primary color correction unit, 1304, 2024, 3024 white correction unit, 1306, 2026, 3026 coefficient calculation unit, 1308, 2028, 3028 Gradation value calculation unit, 1322, 2042, 3042 Primary color gradation conversion unit, 1342, 2062, 3062 White gradation conversion unit, 2044 calculation unit.

Claims (9)

A first one-dimensional look-up table, a second one-dimensional look-up table, and a third one-dimensional look-up table that define tone conversion characteristics for the first primary color, the second primary color, and the third primary color, respectively; The second one-dimensional lookup table is stored, and tone conversion is performed on the first primary gradation value indicating the primary color amount of the first primary color according to the first one-dimensional lookup table. In accordance with the second primary gradation value indicating the primary color amount of the second primary color, and the primary color amount of the third primary color is indicated according to the third one-dimensional lookup table. Gradation conversion is performed on the third primary gradation value, the first secondary gradation value indicating the primary color amount of the first primary color, and the second 2 indicating the primary color amount of the second primary color. A third tone indicating the next gradation value and the primary color amount of the third primary color A first correction unit to obtain a 2 Tsugikai tone values,
A fourth one-dimensional lookup table, a fifth one-dimensional lookup table, and a sixth one-dimensional lookup table that define tone conversion characteristics relating to white are held, and according to the fourth one-dimensional lookup table Gradation conversion is performed on the first primary gradation value, gradation conversion is performed on the second primary gradation value according to the fifth one-dimensional lookup table, and the sixth In accordance with the one-dimensional lookup table, gradation conversion is performed on the third primary gradation value, a fourth secondary gradation value indicating the primary color amount of the first primary color, and the second primary color. A second correction unit for obtaining a fifth secondary gradation value indicating the primary color amount and a sixth secondary gradation value indicating the primary color amount of the third primary color;
From the first primary gradation value, the second primary gradation value, and the third primary gradation value, the first secondary gradation value and the fourth secondary gradation value. The contribution of the first tertiary gradation value indicating the primary color amount of each of the first primary colors is determined to be the first contribution magnitude, and the second secondary gradation value and the The magnitude of the contribution to the second tertiary gradation value indicating the primary color amount of the second primary color of each of the fifth secondary gradation values is determined as the second contribution magnitude, and the third contribution value is determined. The magnitude of the contribution to the third tertiary gradation value indicating the primary color amount of the third primary color of each of the secondary gradation value and the sixth secondary gradation value is the third contribution magnitude. A decision unit to decide on,
The magnitude of the contribution of each of the first secondary gradation value and the fourth secondary gradation value to the first tertiary gradation value is the magnitude of the first contribution. The first tertiary gradation value is derived from the first secondary gradation value and the fourth secondary gradation value, and the second secondary gradation value and the fifth secondary floor are derived. The second secondary gradation value and the fifth secondary floor so that the contribution of each tone value to the second tertiary gradation value is the second contribution. Deriving the second tertiary gradation value from the tone value, and contributing each of the third secondary gradation value and the sixth secondary gradation value to the third tertiary gradation value A derivation unit for deriving the third tertiary gradation value from the third secondary gradation value and the sixth secondary gradation value so that the magnitude of the third contribution value becomes the third contribution magnitude When,
A color correction apparatus comprising: The determination unit may be configured such that the color expressed by the set of the first primary gradation value, the second primary gradation value, and the third primary gradation value becomes closer to white. The contribution of the secondary gradation value to the first tertiary gradation value is reduced, the contribution of the fourth secondary gradation value to the first tertiary gradation value is increased, and The contribution of the second secondary gradation value to the second tertiary gradation value is reduced, and the contribution of the fifth secondary gradation value to the second tertiary gradation value is increased. , Reducing the contribution of the third secondary gradation value to the third tertiary gradation value and reducing the contribution of the sixth secondary gradation value to the third tertiary gradation value. The color correction apparatus according to claim 1, wherein the color correction apparatus is enlarged. The determination unit is an index indicating the proximity of the color represented by the set of the first primary gradation value, the second primary gradation value, and the third primary gradation value to white. And the closer the proximity indicated by the index is, the smaller the contribution of the first secondary gradation value to the first tertiary gradation value is, and the fourth secondary gradation value is calculated. Increasing the contribution of the second secondary gradation value to the second tertiary gradation value, and reducing the contribution of the second secondary gradation value to the second tertiary gradation value. The contribution of the tone value to the second tertiary gradation value is increased, the contribution of the third secondary gradation value to the third tertiary gradation value is decreased, and the sixth 2 3. The color correction apparatus according to claim 2, wherein the contribution of the next gradation value to the third tertiary gradation value is increased. The magnitude of the first contribution is expressed by a first weighting factor and a second weighting factor indicating the weights of the first secondary tone value and the fourth secondary tone value, respectively.
The magnitude of the second contribution is expressed by a third weighting factor and a fourth weighting factor indicating the weights of the second secondary tone value and the fifth secondary tone value, respectively.
The magnitude of the third contribution is expressed by a fifth weighting factor and a sixth weighting factor indicating the weights of the third secondary tone value and the sixth secondary tone value, respectively.
In the first tertiary gradation value, the first secondary gradation value and the fourth secondary gradation value are weighted by the first weighting coefficient and the second weighting coefficient, respectively. A weighted sum of a first secondary gradation value and the fourth secondary gradation value;
In the second tertiary gradation value, the second secondary gradation value and the fifth secondary gradation value are weighted by the third weighting factor and the fourth weighting factor, respectively. A weighted sum of a second secondary tone value and the fifth secondary tone value;
In the third tertiary gradation value, the third secondary gradation value and the sixth secondary gradation value are weighted by the fifth weighting factor and the sixth weighting factor, respectively. 4. The color correction apparatus according to claim 1, wherein the color correction apparatus is a weighted sum of a third secondary gradation value and the sixth secondary gradation value. The magnitude of the first contribution is expressed by a first weighting factor and a second weighting factor indicating the weights of the first secondary tone value and the fourth secondary tone value, respectively.
The magnitude of the second contribution is expressed by the first weight coefficient and the second weight coefficient indicating the weights of the second secondary gradation value and the fifth secondary gradation value, respectively. ,
The magnitude of the third contribution is expressed by the first weight coefficient and the second weight coefficient indicating the weights of the third secondary gradation value and the sixth secondary gradation value, respectively. ,
In the first tertiary gradation value, the first secondary gradation value and the fourth secondary gradation value are weighted by the first weighting coefficient and the second weighting coefficient, respectively. A weighted sum of a first secondary gradation value and the fourth secondary gradation value;
In the second tertiary gradation value, the second secondary gradation value and the fifth secondary gradation value are weighted by the first weighting factor and the second weighting factor, respectively. A weighted sum of a second secondary tone value and the fifth secondary tone value;
In the third tertiary gradation value, the third secondary gradation value and the sixth secondary gradation value are weighted by the first weighting factor and the second weighting factor, respectively. 4. The color correction apparatus according to claim 1, wherein the color correction apparatus is a weighted sum of a third secondary gradation value and the sixth secondary gradation value. The first correction unit includes:
The gradation after the first gradation conversion indicating the primary color amount of the first primary color by performing gradation conversion on the first primary gradation value according to the first one-dimensional lookup table. A second gradation conversion indicating a primary color amount of the second primary color by obtaining a value and performing gradation conversion on the second primary gradation value according to the second one-dimensional lookup table A third gradation value indicating the primary color amount of the third primary color is obtained by obtaining a later gradation value and performing gradation conversion on the third primary gradation value according to the third one-dimensional lookup table. The tone value after the tone conversion is obtained, the tone value after the first tone conversion, the tone value after the second tone conversion, and the tone value after the third tone conversion. Is provided with a gradation converting section for converting the first secondary gradation value, the second secondary gradation value, and the third secondary gradation value, respectively. Any color correction device of claims 1 to 5. The first correction unit includes:
The gradation after the first gradation conversion indicating the primary color amount of the first primary color by performing gradation conversion on the first primary gradation value according to the first one-dimensional lookup table. A second gradation conversion indicating a primary color amount of the second primary color by obtaining a value and performing gradation conversion on the second primary gradation value according to the second one-dimensional lookup table A third gradation value indicating the primary color amount of the third primary color is obtained by obtaining a later gradation value and performing gradation conversion on the third primary gradation value according to the third one-dimensional lookup table. The tone value after tone conversion is obtained, the seventh one-dimensional lookup table, the eighth one-dimensional lookup table, the ninth one-dimensional lookup table, the tenth one-dimensional lookup table, the eleventh One-dimensional lookup table and the twelfth one-dimensional And further performing gradation conversion on the first primary gradation value according to the seventh one-dimensional lookup table and the eighth one-dimensional lookup table, respectively. A seventh tone-converted tone value indicating the primary color amount of the second primary color and an eighth tone-converted tone value indicating the primary color amount of the third primary color are obtained, and the ninth 1 A ninth floor indicating the primary color amount of the first primary color by performing tone conversion on the second primary tone value according to a dimension lookup table and the tenth one-dimensional lookup table. A tone value after tone conversion and a tone value after tenth tone conversion indicating the primary color amount of the third primary color are obtained, and the eleventh one-dimensional lookup table and the twelfth one-dimensional lookup are obtained. According to the table An eleventh gradation-converted gradation value indicating the primary color amount of the first primary color and a primary color amount of the second primary color by performing gradation conversion on the third primary gradation value, respectively. A gradation conversion unit for obtaining a gradation value after the twelfth gradation conversion indicating
The first secondary level is obtained by adding the gradation value after the first gradation conversion, the gradation value after the ninth gradation conversion, and the gradation value after the eleventh gradation conversion. Obtaining the tone value, and adding the tone value after the second tone conversion, the tone value after the seventh tone conversion, and the tone value after the twelfth tone conversion, 2 is obtained, and the gradation value after the third gradation conversion, the gradation value after the eighth gradation conversion, and the gradation value after the tenth gradation conversion are added. A calculation unit that obtains the third secondary gradation value by combining,
The color correction apparatus according to claim 1, further comprising: A display panel comprising a plurality of pixels;
8. The color correction apparatus according to claim 1, wherein for each of the plurality of pixels, the first primary gradation value, the second primary gradation value, and the third primary value. A color correction unit that receives a gradation value and outputs the first tertiary gradation value, the second tertiary gradation value, and the third tertiary gradation value;
Drive for causing each pixel to display a color represented by a set of the first tertiary gradation value, the second tertiary gradation value, and the third tertiary gradation value for each of the plurality of pixels. Circuit,
A display device comprising: a) a first one-dimensional lookup table, a second one-dimensional lookup table, and a third one-dimensional lookup that define the tone conversion characteristics of the first primary color, the second primary color, and the third primary color, respectively. A table is prepared, gradation conversion is performed on a first primary gradation value indicating a primary color amount of the first primary color according to the first one-dimensional lookup table, and the second one-dimensional lookup is performed. A tone conversion is performed on the second primary tone value indicating the primary color amount of the second primary color according to the up table, and the primary color amount of the third primary color according to the third one-dimensional lookup table. Gradation conversion is performed on the third primary gradation value indicating the first secondary gradation value indicating the primary color amount of the first primary color, and the second primary color value indicating the primary color amount of the second primary color. A second gradation value indicating a secondary tone value of the second primary color and a primary color amount of the third primary color Obtaining a gradation value,
b) preparing a fourth one-dimensional lookup table, a fifth one-dimensional lookup table, and a sixth one-dimensional lookup table defining white gradation conversion characteristics; According to the first primary gradation value, gradation conversion is performed on the second primary gradation value according to the fifth one-dimensional lookup table, According to a sixth one-dimensional lookup table, gradation conversion is performed on the third primary gradation value, and a fourth secondary gradation value indicating the primary color amount of the first primary color, the second Obtaining a fifth secondary gradation value indicating the primary color amount of the primary color and a sixth secondary gradation value indicating the primary color amount of the third primary color;
c) From the first primary gradation value, the second primary gradation value, and the third primary gradation value, the first secondary gradation value and the fourth secondary floor The magnitude of the contribution to the first tertiary gradation value indicating the primary color amount of each of the first primary colors of the tone value is determined as the first contribution magnitude, and the second secondary gradation value is determined. And determining the magnitude of the contribution to the second tertiary gradation value indicating the primary color amount of the second primary color of each of the fifth secondary gradation values as the second contribution magnitude, The degree of contribution of the third secondary gradation value and the sixth secondary gradation value to the third tertiary gradation value indicating the primary color amount of the third primary color is set as the third contribution. The process of determining the size of
d) The magnitude of the contribution of each of the first secondary gradation value and the fourth secondary gradation value to the first tertiary gradation value is the magnitude of the first contribution. As described above, the first tertiary gradation value is derived from the first secondary gradation value and the fourth secondary gradation value, and the second secondary gradation value and the fifth 2 The second secondary gradation value and the second 2 so that the magnitude of the contribution of each of the secondary gradation values to the second tertiary gradation value becomes the magnitude of the second contribution. The second tertiary gradation value is derived from the secondary gradation value, and the third tertiary gradation value of each of the third secondary gradation value and the sixth secondary gradation value is obtained. The third tertiary gradation value is derived from the third secondary gradation value and the sixth secondary gradation value so that the magnitude of the contribution becomes the third contribution magnitude. Process,
A color correction method comprising:

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