JP5677021B2 - Color correction processing apparatus, color correction processing method, and multi-display apparatus - Google Patents

Description

  The present invention relates to a color correction processing device and a color correction processing method for correcting color misregistration between a plurality of display panels constituting a multi display, and a multi display device in which the color correction processing device is mounted. It is.

There is a multi-display in which a large screen is achieved by arranging a plurality of display panels side by side.
However, in a multi-display, for example, color misregistration may occur due to slight differences in color reproduction characteristics of a plurality of display panels.
Therefore, in recent years, a color correction processing apparatus that corrects color misregistration between a plurality of display panels constituting a multi-display has been developed.

For example, in the color correction processing device disclosed in Patent Document 1 below, images displayed on a plurality of display panels are captured, and color shifts between the plurality of display panels are corrected based on the captured images. Yes.
That is, in this color correction processing apparatus, first, an image displayed on a plurality of display panels is captured using a camera, and an adjustment range of display characteristics on each display panel is calculated from the captured images.
Then, the range in which the adjustment areas of the respective display panels overlap is specified, and the color shift between the plurality of display panels is corrected by setting the adjustment degree of each display panel within the overlapping range.

JP 2005-057507 A (paragraph numbers [0024] to [0027], FIG. 1)

  Since the conventional color correction processing apparatus is configured as described above, it is possible to prevent re-adjustment of display characteristics for each display panel and to save useless labor. However, even if the images displayed on the plurality of display panels are photographed and the color shift between the plurality of display panels is corrected based on the photographed images, the white balance between the photographed images on the plurality of display panels, for example, If the brightness and brightness are different, there is a problem that the color misregistration cannot be corrected accurately.

The present invention has been made to solve the above-described problems, and an object thereof is to obtain a color correction processing apparatus and a color correction processing method capable of accurately correcting a color shift between a plurality of display panels. .
It is another object of the present invention to obtain a multi-display device equipped with a color correction processing device that can accurately correct a color shift between a plurality of display panels.

The color correction processing apparatus according to the present invention includes color correction image display means for displaying color correction images on a plurality of display panels constituting a multi-display, and colors displayed on the plurality of display panels. A captured image acquisition unit that captures an image for correction and acquires the captured image, an image adjustment processing unit that performs image adjustment processing on the captured image acquired by the captured image acquisition unit, and image adjustment performed by the image adjustment processing unit Target chromaticity calculation means for calculating target chromaticity, which is chromaticity representing target color reproduction characteristics in a plurality of display panels, from the captured image after processing, and the target chromaticity calculated by the target chromaticity calculation means and a plurality the color correction coefficient calculating means for calculating a color correction coefficient from the chromaticity of the display panel, using the color correction coefficients calculated by the color correction coefficient calculating means, double Color correction means for correcting the color of the display panel, and when the target chromaticity calculation means calculates the target chromaticity in the plurality of display panels, the display arranged in the periphery for each of the plurality of display panels The value obtained by multiplying the filter coefficient used for noise removal in the panel by the value indicating the target chromaticity of the display panel arranged in the periphery is set as the target chromaticity .

According to the present invention, color correction image display means for displaying color correction images on a plurality of display panels constituting a multi-display, and color correction images displayed on the plurality of display panels A captured image acquisition unit that acquires the captured image, an image adjustment processing unit that performs an image adjustment process on the captured image acquired by the captured image acquisition unit, and a photographing after the image adjustment process by the image adjustment processing unit Target chromaticity calculation means for calculating target chromaticity, which is chromaticity representing target color reproduction characteristics in a plurality of display panels, from the image; target chromaticity calculated by the target chromaticity calculation means; a color correction coefficient calculating means for calculating a color correction coefficient from the chromaticity, by using the calculated color correction coefficient by the color correction coefficient calculating means, a plurality of Display Color correction means for performing color correction of the panel, and when the target chromaticity calculation means calculates the target chromaticity in the plurality of display panels, each of the plurality of display panels is a display panel arranged in the periphery. Since the value obtained by multiplying the filter coefficient used for noise removal by the value indicating the target chromaticity of the display panel arranged in the periphery is summed to be the target chromaticity , There is an effect that the color misregistration can be accurately corrected.

It is a block diagram which shows the multi-display apparatus by which the color correction processing apparatus by Embodiment 1 of this invention is mounted. It is explanatory drawing which shows the structural example of a multi display. It is a flowchart which shows the processing content (color correction processing method) of the color correction processing apparatus by Embodiment 1 of this invention. 5 is a flowchart showing a calculation process of a common area of a color reproduction area in a target chromaticity calculation processing unit 15. It is explanatory drawing which shows how to obtain | require the common area | region of a color reproduction area. (A) shows arrangement | positioning of the display panels D0-D8 which comprise a multi-display, (b) is explanatory drawing which shows the filter coefficients K0-K8 set to the display panels D0-D8. It is a block diagram which shows the multi-display apparatus by which the color correction processing apparatus by Embodiment 4 of this invention is mounted.

Embodiment 1 FIG.
FIG. 1 is a block diagram showing a multi-display apparatus in which a color correction processing apparatus according to Embodiment 1 of the present invention is mounted.
FIG. 2 is an explanatory diagram showing a configuration example of a multi-display.
In FIG. 1, a multi-display 1 is a large-screen display device composed of a plurality of display panels.
In the example of FIG. 2, the multi-display 1 is configured by arranging nine display panels D0 to D8.
Although FIG. 2 shows an example in which nine display panels D0 to D8 are arranged, it goes without saying that the number of display panels is not limited to nine.

The image display device 2 is a device that displays various images on the display panels D0 to D8 after the color correction between the display panels D0 to D8 is corrected by the color correction processing device 3.
The color correction processing device 3 is a device that corrects color misregistration between the nine display panels D0 to D8.

The color correction image display unit 11 of the color correction processing device 3 is configured by, for example, a GPU (Graphics Processing Unit) and the like, and is used for color correction with respect to the nine display panels D0 to D8 constituting the multi-display 1. The process of displaying the image is performed. The color correction image display unit 11 constitutes a color correction image display means.
A digital still camera (hereinafter referred to as “DSC”) 12 shoots a color correction image displayed on the display panels D0 to D8 under the instruction of the image acquisition processing unit 13, and a RAW image that is the captured image. Is executed to output to the image acquisition processing unit 13.

The image acquisition processing unit 13 is composed of, for example, a semiconductor integrated circuit or a one-chip microcomputer on which a CPU is mounted. When a signal indicating completion of display of the color correction image is received from the color correction image display unit 11, The imaging command is output to the DSC 12 and processing for acquiring RAW image data indicating the RAW image from the DSC 12 is performed.
The DSC 12 and the image acquisition processing unit 13 constitute a captured image acquisition unit.

The image adjustment processing unit 14 includes, for example, a GPU or the like, and performs a process of adjusting the white balance of the RAW image as an image adjustment process for the RAW image indicated by the RAW image data acquired by the image acquisition processing unit 13. .
In the first embodiment, an example in which the image adjustment processing unit 14 adjusts the white balance of a RAW image as an image adjustment process for the RAW image will be described. However, the luminance of the RAW image may be adjusted.
The image adjustment processing unit 14 constitutes an image adjustment processing unit.

  The target chromaticity calculation processing unit 15 is composed of, for example, a semiconductor integrated circuit mounted with a CPU, a one-chip microcomputer, or the like. Processing for calculating target chromaticity, which is chromaticity representing target color reproduction characteristics, is performed. The target chromaticity calculation processing unit 15 constitutes target chromaticity calculation means.

The color correction coefficient calculation processing unit 16 includes, for example, a semiconductor integrated circuit or a one-chip microcomputer mounted with a CPU, and the target chromaticity calculated by the target chromaticity calculation processing unit 15 and the display panels D0 to D8. A process of calculating a color correction coefficient from the chromaticity is performed. The color correction coefficient calculation processing unit 16 constitutes a color correction coefficient calculation unit.
The color correction processing unit 17 is composed of, for example, a GPU, and performs color correction processing of the display panels D0 to D8 using the color correction coefficient calculated by the color correction coefficient calculation processing unit 16. The color correction processing unit 17 constitutes a color correction unit.

In the example of FIG. 1, the color correction image display unit 11, DSC 12, image acquisition processing unit 13, image adjustment processing unit 14, target chromaticity calculation processing unit 15, and color correction coefficient calculation, which are components of the color correction processing device 3. Although it is assumed that each of the processing unit 16 and the color correction processing unit 17 is configured by dedicated hardware, when the color correction processing device 3 is configured by a computer, the color correction image display unit 11, A program describing the processing contents of the DSC 12, the image acquisition processing unit 13, the image adjustment processing unit 14, the target chromaticity calculation processing unit 15, the color correction coefficient calculation processing unit 16 and the color correction processing unit 17 is stored in the memory of the computer. Then, the CPU of the computer may execute a program stored in the memory.
FIG. 3 is a flowchart showing the processing contents (color correction processing method) of the color correction processing apparatus according to Embodiment 1 of the present invention.

Next, the operation will be described.
The color correction image display unit 11 of the color correction processing device 3 displays images for color correction on the nine display panels D0 to D8 constituting the multi-display 1 (step ST1).
That is, the color correction image display unit 11 displays R (red), G (green), and B (blue) monochrome images and W ( White and Bk (black) images are displayed simultaneously.
When the color correction image display unit 11 displays the color correction image on the display panels D0 to D8, the color correction image display unit 11 outputs a signal indicating the completion of display of the color correction image to the image acquisition processing unit 13.

Upon receiving a signal indicating completion of display of the color correction image from the color correction image display unit 11, the image acquisition processing unit 13 outputs an image capturing command to the DSC 12.
When the DSC 12 receives an image capturing command from the image acquisition processing unit 13, the DSC 12 captures an image for color correction displayed on the display panels D <b> 0 to D <b> 8, and displays RAW image data indicating the RAW image as the captured image. The data is output to the acquisition processing unit 13 (step ST2).
At this time, it is assumed that the shooting position of the DSC 12 is adjusted so that the entire display images of the nine display panels D0 to D8 are within the shooting range of the DSC 12. Alternatively, it is assumed that adjustment is performed using a telephoto or wide-angle lens so as to be within the photographing range of the DSC 12.
Further, the shutter speed and aperture of the DSC 12 are adjusted according to the purpose, and when correcting the display panels D0 to D8, they are adjusted slightly blurry with the telephoto lens.
The image acquisition processing unit 13 acquires RAW image data indicating a RAW image output from the DSC 12.

When the image acquisition processing unit 13 acquires RAW image data indicating a RAW image, the image adjustment processing unit 14 adjusts the white balance of the RAW image as an image adjustment process for the RAW image (step ST3).
Hereinafter, the white balance adjustment processing by the image adjustment processing unit 14 will be described in detail.

First, the image adjustment processing unit 14 refers to the RAW image data output from the image acquisition processing unit 13 and specifies an area where a W (white) image is displayed for each of the display panels D0 to D8. The average RGB value of the W (white) image is calculated.
When calculating the average RGB value of the W (white) image for each of the display panels D0 to D8, the image adjustment processing unit 14 obtains a further average of these average values.
That is, by calculating the average of the average RGB values of the W (white) image obtained for each of the display panels D0 to D8, the W (white) image in the entire nine display panels D0 to D8 (multi-display). Average RGB values (R _ave , G _ave , B _ave ) are obtained.

The image adjustment processing unit 14 obtains an average RGB value (R _ave , G _ave , B _ave ) of W (white) images in the entire nine display panels D0 to D8 (multi-display), and the following formula ( As shown in 1), a white balance correction coefficient Wb _R for red correction and a white balance correction coefficient Wb _B for blue correction are calculated from the average RGB values (R _ave , G _ave , B _ave ).
Wb _R = R _ave / G _ave
Wb _B = B _ave / G _ave
(1)

Image adjustment processing unit 14, calculating the white balance correction coefficient Wb _B for white balance correction coefficient Wb _R and the blue correction for red correction, as shown in the following formula (2), the white balance correction coefficient Wb _R , Wb _B are used to adjust the white balance of the RAW image.
Rout = Wb _R × Rin
Gout = Gin
Bout = Wb _B × Bin
(2)
In Equation (2), Rin, Gin, and Bin are RGB signals of a W (white) image, and Rout, Gout, and Bout are RGB signals after white balance adjustment of the image.
Note that the image adjustment processing unit 14 performs white balance adjustment on all the color correction images to obtain a RAW image after white balance adjustment processing.

When the image adjustment processing unit 14 adjusts the white balance of the RAW image, the target chromaticity calculation processing unit 15 represents the target color reproduction characteristics in the nine display panels D0 to D8 from the RAW image after the white balance adjustment processing. A target chromaticity which is a chromaticity is calculated (step ST4).
That is, the target chromaticity calculation processing unit 15 obtains a common color gamut (Rt, Gt, Bt) in the nine display panels D0 to D8, and xy of the common color gamut (Rt, Gt, Bt). The value (color display value) is calculated as the target chromaticity.
For example, a common area between the color reproduction area of the display panel D1 and the color reproduction area of the display panel D2 is obtained, and a common area between the common area and the color reproduction area of the display panel D3 is obtained.
By sequentially obtaining a common area between the common area and the color reproduction area of the remaining display panel D, a common area of the color reproduction area in the display panels D0 to D8 is finally obtained, and an xy value of the common area is obtained. Calculate as target chromaticity.

The target chromaticity calculation processing by the target chromaticity calculation processing unit 15 will be specifically described below.
FIG. 4 is a flowchart showing the calculation process of the common area of the color gamut in the target chromaticity calculation processing unit 15.
First, the target chromaticity calculation processing unit 15 calculates an average RGB value (Rout, Gout, Bout) in the RAW image after the white balance adjustment process for each of the display panels D0 to D8.

ただし、式（３）では、マトリクス係数として、ｓＲＧＢの変換係数を用いているが、これは一例に過ぎず、例えば、ディスプレイパネルＤ０〜Ｄ８の測色結果を適用するようにしてもよい。 Next, the target chromaticity calculation processing unit 15 calculates XYZ values (color display values) from the average RGB values (Rout, Gout, Bout) as shown in the following formula (3).

However, in Equation (3), the sRGB conversion coefficient is used as the matrix coefficient, but this is only an example, and for example, the color measurement results of the display panels D0 to D8 may be applied.

Next, the target chromaticity calculation processing unit 15 calculates an xy value (color display value) from the XYZ value as shown in the following equation (4).
R (xr, yr): xr = Xr / (Xr + Yr + Zr)
yr = Yr / (Xr + Yr + Zr)
G (xg, yg): xg = Xg / (Xg + Yg + Zg)
yg = Yg / (Xg + Yg + Zg)
B (xb, yb): xb = Xb / (Xb + Yb + Zb)
yb = Yb / (Xb + Yb + Zb)
(4)

When the target chromaticity calculation processing unit 15 calculates the xy value from the XYZ value, the target chromaticity calculation unit 15 uses the xy value to obtain a common area of the color gamut in the display panels D0 to D8, and calculates the xy value of the common area as the target chromaticity. Calculate as
Here, FIG. 5 is an explanatory diagram showing how to obtain the common area of the color reproduction area.
In FIG. 5, R1 (xr1, yr1), G1 (xg1, yg1), and B1 (xb1, yb1) are the vertices of a triangle indicating the color gamut of the display panel D1.
R2 (xr2, yr2), G2 (xg2, yg2), and B2 (xb2, yb2) are the vertices of a triangle indicating the color reproduction range of the display panel D2.
Rt (xrt, yrt), Gt (xgt, ygt), and Bt (xbt, ybt) are the vertices of a triangle indicating a common area between the color reproduction area of the display panel D1 and the color reproduction area of the display panel D2.

The target chromaticity calculation processing unit 15 is a common area (Rt, Gt, Bt) for the color gamut (R1, G1, B1) of the display panel D1 and the color gamut (R2, G2, B2) of the display panel D2. First, it is determined whether or not the vertex R1 (xr1, yr1) and the vertex R2 (xr2, yr2) match (step ST11).
When the vertex R1 (xr1, yr1) and the vertex R2 (xr2, yr2) match (R1 = R2), the target chromaticity calculation processing unit 15 Rt (xrt, yrt) that is one vertex of the common area Is set as follows (step ST12).
Rt (xrt, yrt) = R1 (xr1, yr1) = R2 (xr2, yr2)

In the example of FIG. 5, since the vertex R1 (xr1, yr1) and the vertex R2 (xr2, yr2) do not match (R1 ≠ R2), the target chromaticity calculation processing unit 15 determines that the vertex R1 (xr1, yr1) It is determined whether or not it is included (included) in the triangle R2G2B2 (step ST13).
Whether or not the vertex R1 (xr1, yr1) is included in the triangle R2G2B2 is determined as follows.
A vector from the vertex R1 (xr1, yr1), which is a point to be determined for inclusion, to the vertex (R2, G2, B2) of the triangle R2G2B2 is obtained.
Vector R1R2 = (xr2-xr1, yr2-yr1)
Vector R1G2 = (xg2-xr1, yg2-yr1)
Vector R1B2 = (xb2-xr1, yb2-yr1)
(5)

Next, outer products among the three vectors R1R2, R1G2, and R1B2 are obtained.
Vector R1R2 x Vector R1G2
= (Xr2-xr1) * (yg2-yr1)-(yr2-yr1) * (xg2-xr1)
Vector R1G2 x Vector R1B2
= (Xg2-xr1) * (yb2-yr1)-(yg2-yr1) * (xb2-xr1)
Vector R1B2 × vector R1R2
= (Xb2-xr1) * (yr2-yr1)-(yb2-yr1) * (xr2-xr1)
(6)

If all of the outer products among the three vectors R1R2, R1G2, and R1B2 are 0 or more, it is determined that the vertex R1 (xr1, yr1) is included in the triangle R2G2B2, and any negative value can be obtained. For example, it is determined that the vertex R1 (xr1, yr1) is not included in the triangle R2G2B2.
When the vertex R1 (xr1, yr1) is included in the triangle R2G2B2, the target chromaticity calculation processing unit 15 sets Rt (xrt, yrt) that is one vertex of the common area as follows (step ST14). ).
Rt (xrt, yrt) = R1 (xr1, yr1)

In the example of FIG. 5, since the vertex R1 (xr1, yr1) is not included in the triangle R2G2B2, the target chromaticity calculation processing unit 15 includes (includes) the vertex R2 (xr2, yr2) in the triangle R1G1B1. Whether or not) (step ST15).
Whether or not the vertex R2 (xr2, yr2) is included in the triangle R1G1B1 is determined as follows.
A vector from the vertex R2 (xr2, yr2), which is a point to be determined for inclusion, to the vertex (R1, G1, B1) of the triangle R1G1B1 is obtained.
Vector R2R1 = (xr1-xr2, yr1-yr2)
Vector R2G1 = (xg1-xr2, yg1-yr2)
Vector R2B1 = (xb1-xr2, yb1-yr2)
(7)

Next, outer products among the three vectors R2R1, R2G1, and R2B1 are obtained.
Vector R2R1 x Vector R2G1
= (Xr1-xr2) * (yg1-yr2)-(yr1-yr2) * (xg1-xr2)
Vector R2G1 × vector R2B1
= (Xg1-xr2) * (yb1-yr2)-(yg1-yr2) * (xb1-xr2)
Vector R2B1 × vector R2R1
= (Xb1-xr2) * (yr1-yr2)-(yb1-yr2) * (xr1-xr2)
(8)

If all the outer products among the three vectors R2R1, R2G1, and R2B1 are 0 or more, it is determined that the vertex R2 (xr2, yr2) is included in the triangle R1G1B1, and even if one of them is a negative value For example, it is determined that the vertex R2 (xr2, yr2) is not included in the triangle R1G1B1.
When the vertex R2 (xr2, yr2) is included in the triangle R1G1B1, the target chromaticity calculation processing unit 15 sets Rt (xrt, yrt) that is one vertex of the common area as follows (step ST16). ).
Rt (xrt, yrt) = R2 (xr2, yr2)

In the example of FIG. 5, since the vertex R2 (xr2, yr2) is not included in the triangle R1G1B1, the target chromaticity calculation processing unit 15 determines whether or not the line segment R1G1 and the line segment R2B2 intersect (Step S1). ST17).
Whether the line segment R1G1 and the line segment R2B2 intersect each other is determined as follows.
Assuming that the intersection of the line segment R1G1 and the line segment R2B2 is T (xrt, yrt), when solving the following equation (9), if 0 ≦ u and v ≦ 1, it is determined that there is an intersection. If 0 ≦ u and v ≦ 1, it is determined that there is no intersection.
xrt = xr1 + u (xg1-xr1)
xr1 + u (xg1-xr1) = xr2 + v (xb2-xr2)
xrt = xr2 + v (xb2-xr2)
u (xg1-xr1) + v (xr2-xb2) = xr2-xr1
yrt = yr1 + u (yg1-yr1)
yr1 + u (yg1-yr1) = yr2 + v (yb2-yr2)
yrt = yr2 + v (yb2-yr2)
u (yg1-yr1) + v (yr2-yb2) = yr2-yr1
(9)

When the line segment R1G1 and the line segment R2B2 intersect, the target chromaticity calculation processing unit 15 sets Rt (xrt, yrt), which is one vertex of the common area, as the intersection of the line segment R1G1 and the line segment R2B2. (Step ST18).
In the example of FIG. 5, since the line segment R1G1 and the line segment R2B2 intersect, the vertex Rt (xrt, yrt) is set as the intersection of the line segment R1G1 and the line segment R2B2.
If the line segment R1G1 and the line segment R2B2 do not intersect, Rt (xrt, yrt), which is one vertex of the common area, is set as the intersection of the line segment R1B1 and the line segment R2G2 (step ST19).

Up to this point, the target chromaticity calculation processing unit 15 has described the operation of setting one vertex of the common area, Rt (xrt, yrt), but Gt (xgt, ygt), which is the other vertex of the common area. , Bt (xbt, ybt) are set in the same manner as in the case of setting the vertex Rt (xrt, yrt).
In the example of FIG. 5, the vertex G1 and the vertex G2 do not match, and the vertex G1 (xg1, yg1) is not included in the triangle R2G2B2. Further, the vertex G2 (xg2, yg2) is not included in the triangle R1G1B1. However, since the line segment G1B1 and the line segment G2R2 intersect, the vertex Gt (xgt, ygt) is set to the intersection of the line segment G1B1 and the line segment G2R2.
In the example of FIG. 5, the vertex B1 and the vertex B2 do not match, but since the vertex B2 (xb2, yb2) is included in the triangle R1G1B1, the vertex Bt (xbt, ybt) matches the vertex B2. Set to the point to be

Up to this point, the target chromaticity calculation processing unit 15 has described the operation for obtaining the common area between the color reproduction area of the display panel D1 and the color reproduction area of the display panel D2. By finding a common area between the area and the color gamut of the remaining display panel D, the common area of the color gamut in the display panels D0 to D8 is finally obtained.
When the target chromaticity calculation processing unit 15 obtains the common area (Rt, Gt, Bt) of the color gamut in the display panels D0 to D8, the xy value of the common area (Rt, Gt, Bt) is set as the target chromaticity. decide.
That is, the target chromaticity calculation processing unit 15 determines the target chromaticity of R as (xrt, yrt), the target chromaticity of G as (xgt, ygt), and the target chromaticity of B as (xbt, ybt).

When the target chromaticity calculation processing unit 15 calculates the target chromaticity, the color correction coefficient calculation processing unit 16 calculates the color from the target chromaticity and the chromaticities of the display panels D0 to D8 as shown in the following equation (10). As a correction coefficient, a matrix coefficient for color correction is calculated (step ST5). However, the color correction matrix coefficient is calculated for each of the display panels D0 to D8.

In equation (10),
・ RGB, Bk XYZ values of display panel D
R: (Xr, Yr, Zr)
G: (Xg, Yg, Zg)
B: (Xb, Yb, Zb)
Bk: (Xbk, Ybk, Zbk)
・ Target chromaticity
Rt (Xrt, Yrt, Zrt)
Gt (Xgt, Ygt, Zgt)
Bt (Xbt, Ybt, Zbt)
However, the target luminance Y is the minimum luminance among the display panels D0 to D8.
The target luminance value is used.
Yrt = (minimum Yr in display panels D0 to D8)
Ygt = (minimum Yg in display panels D0 to D8)
Ybt = (minimum Yb in display panels D0 to D8)
・ Color correction matrix coefficient
RR, GR, BR
RG, GG, GB
RB, GB, BB

  Here, an example in which the target luminance Y is the minimum luminance in the display panels D0 to D8 has been shown, but this is merely an example. For example, the average value or median value of the luminance of the display panels D0 to D8 is shown. A statistical value such as may be used.

ただし、式（１１）において、Ｒ＿ｉｎ，Ｇ＿ｉｎ，Ｂ＿ｉｎはディスプレイパネルＤ０〜Ｄ８に入力されるＲＧＢ値であり、Ｒ＿ｏｕｔ，Ｇ＿ｏｕｔ，Ｂ＿ｏｕｔはディスプレイパネルＤ０〜Ｄ８から出力されるＲＧＢ値である。 When the color correction coefficient calculation processing unit 16 calculates the color correction matrix coefficient, the color correction processing unit 17 uses the color correction matrix coefficient as shown in the following equation (11) to display the display panels D0 to D8. Color correction processing (color correction matrix calculation) is performed (step ST6).

However, in Expression (11), R_in, G_in, and B_in are RGB values input to the display panels D0 to D8, and R_out, G_out, and B_out are RGB values output from the display panels D0 to D8.

As apparent from the above, according to the first embodiment, the color correction image display unit 11 for displaying the color correction image on the display panels D0 to D8 constituting the multi-display 1, and the display An image acquisition processing unit 13 that acquires a RAW image that is a captured image from the DSC 12 that captures the image for color correction displayed on the panels D0 to D8, and a white balance adjustment for the RAW image acquired by the image acquisition processing unit 13 The target color for calculating the target chromaticity, which is the chromaticity representing the target color reproduction characteristics in the display panels D0 to D8, from the image adjustment processing unit 14 that performs the above and the RAW image after the white balance adjustment processing by the image adjustment processing unit 14 Degree calculation processing unit 15, target chromaticity calculated by target chromaticity calculation processing unit 15, and colors of display panels D0 to D8 A color correction coefficient calculation processing unit 16 that calculates a color correction coefficient from the color correction coefficient calculation unit 17, and the color correction processing unit 17 uses the color correction coefficient calculated by the color correction coefficient calculation processing unit 16 to correct the color of the display panels D 0 to D 8. Therefore, the color misregistration between the display panels D0 to D8 can be accurately corrected.
That is, after adjusting the image captured by the DSC 12, the target chromaticity is calculated by obtaining the common area of the color gamut from the image after the adjustment process, so that the images on the display panels D0 to D8. Even if the white balance and the luminance are different, color correction of the display panels D0 to D8 can be performed with high accuracy. Also, the color correction matrix coefficient can be easily calculated using the DSC 12.

  In the first embodiment, the multi-display 1 is composed of 3 × 3 display panels D0 to D8. However, the number of display panels constituting the multi-display 1 is not limited to this. As long as there are two or more display panels, any number may be used.

Embodiment 2. FIG.
In Embodiment 1 described above, the display panel D0 to D8 is subjected to color correction for the display panel. However, the present invention is not limited to this, and for example, for each element of the display display such as an LED display panel. Even when color correction is performed, the present invention can be applied.
Hereinafter, a method for performing color correction for each element of the display will be described.

  The color correction image display unit 11, the image acquisition processing unit 13, the image adjustment processing unit 14, the target chromaticity calculation processing unit 15, the color correction coefficient calculation processing unit 16, and the color correction processing unit 17 are basically configured as described above. The same processing as in the first embodiment is performed, but the processing unit is different for each element of the display panel, not for each display panel.

That is, the color correction image display unit 11 displays the color correction image on all the elements of the display panels D0 to D8.
When the image acquisition processing unit 13 uses the DSC 12 to capture an image for color correction, the image acquisition processing unit 13 adjusts and captures the image so that each element of the display panels D0 to D8 can be separated.
In addition, the angle of view is set so that all the adjusted elements are included in one image. However, if there are too many elements to be adjusted, the image is divided and shot.

When obtaining the average RGB value from the W (white) image, the image adjustment processing unit 14 calculates the average RGB value for each element in the display panels D0 to D8, and obtains an average of those average values. An average RGB value (R _ave , G _ave , B _ave ) of the image is obtained.
Then, as in the first embodiment, the image adjustment processing unit 14 calculates the white balance correction coefficient Wb _R for red correction from the average RGB value (R _ave , G _ave , B _ave ) according to the equation (1). And a white balance correction coefficient Wb _B for blue correction are calculated.
When the image adjustment processing unit 14 calculates the white balance correction coefficient Wb _R for red correction and the white balance correction coefficient Wb _B for blue correction, the white balance is calculated by Expression (2) as in the first embodiment. The white balance of the RAW image is adjusted using the correction coefficients Wb _R and Wb _B.
Note that the image adjustment processing unit 14 performs white balance adjustment on all the color correction images to obtain a RAW image after white balance adjustment processing.

The target chromaticity calculation processing unit 15 obtains a common color gamut (Rt, Gt, Bt) of each element in the nine display panels D0 to D8, and calculates the target chromaticity of each element in the display panels D0 to D8. calculate.
That is, in the first embodiment, when the average RGB values (Rout, Gout, Bout) in the RAW image after the white balance adjustment process are calculated, the average RGB values (Rout, Gout, Bout) are displayed for each of the display panels D0 to D8. In the second embodiment, an average RGB value (Rout, Gout, Bout) is calculated for each element in the display panels D0 to D8.
After calculating the average RGB values (Rout, Gout, Bout), the target chromaticity of each element in the display panels D0 to D8 is calculated by performing the same processing as in the first embodiment.

When the target chromaticity calculation processing unit 15 calculates the target chromaticity of each element, the color correction coefficient calculation processing unit 16 calculates the above formula from the target chromaticity of each element and the chromaticity of each element in the display panels D0 to D8. Using (10), a matrix coefficient for color correction for each element is calculated.
When the color correction coefficient calculation processing unit 16 calculates the color correction matrix coefficient, the color correction processing unit 17 uses the color correction matrix coefficient according to the above equation (11), and uses the color correction matrix coefficient to display each element in the display panels D0 to D8. The color correction process (color correction matrix calculation) is performed.

  According to the second embodiment, after performing the adjustment process of the image photographed by the DSC 12, the target chromaticity is calculated by obtaining the common area of the color gamut of each element from the image after the adjustment process. Therefore, color correction is performed for each element of the display panels D0 to D8, and there is an effect that fine color unevenness can be eliminated.

Embodiment 3 FIG.
In the first embodiment, the target chromaticity calculation processing unit 15 calculates the target chromaticity of the display panels D0 to D8 from the RAW image after the white balance adjustment processing by the image adjustment processing unit 14. When calculating the target chromaticity of the display panels D0 to D8, if the display panel for which the target chromaticity is to be calculated is, for example, the display panel D0, the display panels D1 to D8 arranged around the display panel D0. The target chromaticity of the display panel D0 may be calculated in consideration of filter coefficients (for example, epsilon filter coefficients, low-pass filter coefficients, etc.).

FIG. 6A shows the arrangement of display panels D0 to D8 constituting a multi-display, and FIG. 6B shows filter coefficients K0 to K8 set for the display panels D0 to D8.
The target chromaticity calculation processing unit 15 obtains a common area (Rt, Gt, Bt) of the color gamut in the display panels D0 to D8 in the same manner as in the first embodiment.

In the first embodiment, the xy value of the common area (Rt, Gt, Bt) of the color gamut in the display panels D0 to D8 is determined as the target chromaticity (the target chromaticity of R is (xrt, yrt), The target chromaticity is determined as (xgt, ygt) and the target chromaticity of B is set as (xbt, ybt). In the second embodiment, the xy value of the common area (Rt, Gt, Bt) is calculated. When the display panel for which the target chromaticity is to be calculated is, for example, the display panel D0, it is common in consideration of the filter coefficients K0 to K8 of the display panels D1 to D8 arranged around the display panel D0. The xy value of the region (Rt, Gt, Bt) is calculated.
For example, if one of xy values indicating the target chromaticity of R is xr_t, xr_Di (i = 0, 1, 2, 2) which is the xy value of the display panels D0 to D8 as shown in the following equation (12). .., 8) are multiplied by the filter coefficients Ki (i = 0, 1, 2,..., 8) of the display panels D0 to D8, and the sum of the multiplication results is xr_t.

Also, assuming that one of the xy values indicating the target chromaticity of R is yr_t, yr_Di (i = 0, 1, 2, 2) which is the xy value of the display panels D0 to D8, as shown in the following equation (13). .., 8) are multiplied by the filter coefficients Ki (i = 0, 1, 2,..., 8) of the display panels D0 to D8, and the sum of the multiplication results is yr_t.

  Here, an example of calculating the R target chromaticity Rt (xr_t, yr_t) has been shown, but the G target chromaticity Gt (xg_t, yg_t) and the B target chromaticity Bt (xb_t, yb_t) are also R. Similar to the target chromaticity Rt (xr_t, yr_t), the filter coefficient Ki is taken into consideration.

As apparent from the above, according to the third embodiment, when calculating the target chromaticity of the display panels D0 to D8, for example, if the display panel to be calculated for the target chromaticity is the display panel D0, Since the target chromaticity of the display panel D0 is calculated in consideration of the filter coefficients of the display panels D1 to D8 arranged around the display panel D0, the display panel D0 is not reduced without narrowing the color reproduction range. There exists an effect which can perform color correction of -D8.
For example, if an epsilon filter coefficient is set as the filter coefficient Ki, color unevenness between adjacent display panels can be corrected with higher accuracy.

Here, the present invention is applied to the first embodiment and corrects the color misregistration between the display panels D0 to D8. However, the present invention is applied to the second embodiment and the elements in the display panels D0 to D8 are corrected. Color misregistration may be corrected.
Further, when calculating the target luminance Y, a filtering technique (a technique that considers the filter coefficient of a display panel arranged in the vicinity) may be applied.

Embodiment 4 FIG.
FIG. 7 is a block diagram showing a multi-display apparatus in which the color correction processing apparatus according to Embodiment 1 of the present invention is mounted.
In this Embodiment 4, the example which can respond to the form in which a some multi display is installed like a digital signage system, for example is shown.

In FIG. 4, multi-displays 1a and 1b are large-screen display devices composed of a plurality of display panels.
In the example of FIG. 7, a multi-display 1a is configured by arranging two display panels D1 and D2, and a multi-display 1b is configured by arranging two display panels D3 and D4.
Although FIG. 7 shows an example in which two display panels D are arranged, it goes without saying that the number of display panels D is not limited to two.
Needless to say, the number of multi-displays is not limited to two.

The image display device 4 is a device that displays various images on the display panels D1 to D4 after the color correction processing device 5 corrects the color shift between the display panels D1 and D2 and between the display panels D3 and D4.
The color correction processing device 5 is a device that corrects a color shift between the display panels D1 and D2 and corrects a color shift between the display panels D3 and D4.

Under the instruction of the image acquisition processing unit 22, the DSC 12 a captures the image for color correction displayed on the display panels D 1 and D 2, and sends RAW image data indicating the RAW image as the captured image to the image acquisition processing unit 22. Perform the output process.
Under the instruction of the image acquisition processing unit 22, the DSC 12 b captures a color correction image displayed on the display panels D 3 and D 4, and sends RAW image data indicating the RAW image as the captured image to the image acquisition processing unit 22. Perform the output process.
The color correction image display unit 21 is composed of, for example, a GPU or the like, displays images for color correction on the two display panels D1 and D2 constituting the multi display 1a, and displays the multi display 1b. A process of displaying an image for color correction on the two display panels D3 and D4 that are configured is performed. The color correction image display unit 21 constitutes a color correction image display means.

The image acquisition processing unit 22 is composed of, for example, a semiconductor integrated circuit mounted with a CPU, a one-chip microcomputer, or the like. When receiving a signal indicating completion of display of the color correction image from the color correction image display unit 21, the image acquisition processing unit 22 Is output to the DSCs 12a and 12b, and processing for acquiring RAW image data indicating a RAW image from the DSCs 12a and 12b is performed.
The DSCs 12a and 12b and the image acquisition processing unit 22 constitute a captured image acquisition unit.

The image adjustment processing unit 23 includes, for example, a GPU, and performs a process for adjusting the white balance of the RAW image as an image adjustment process for the RAW image indicated by the RAW image data acquired by the image acquisition processing unit 22. .
In the first embodiment, an example in which the image adjustment processing unit 23 adjusts the white balance of a RAW image as an image adjustment process for the RAW image will be described. However, the luminance of the RAW image may be adjusted.
The image adjustment processing unit 23 constitutes an image adjustment processing unit.

  The target chromaticity calculation processing unit 24 includes, for example, a semiconductor integrated circuit mounted with a CPU, a one-chip microcomputer, and the like. From the captured image after the image adjustment processing by the image adjustment processing unit 23, two display panels D1 , D2 to calculate the target chromaticity that is the chromaticity representing the target color reproduction characteristic, and to calculate the target chromaticity that is the chromaticity representing the target color reproduction characteristic in the two display panels D3 and D4. carry out. The target chromaticity calculation processing unit 24 constitutes target chromaticity calculation means.

The color correction coefficient calculation processing unit 25 includes, for example, a semiconductor integrated circuit mounted with a CPU, a one-chip microcomputer, and the like, and the target chromaticity calculated by the target chromaticity calculation processing unit 24 and the display panels D1 to D4. A process of calculating a color correction coefficient from the chromaticity is performed. The color correction coefficient calculation processing unit 25 constitutes a color correction coefficient calculation unit.
The color correction processing unit 26 is configured by, for example, a GPU, and performs color correction processing of the display panels D1 to D4 using the color correction coefficient calculated by the color correction coefficient calculation processing unit 25. The color correction processing unit 26 constitutes a color correction unit.

  In the example of FIG. 7, the color correction image display unit 21, DSCs 12 a and 12 b, the image acquisition processing unit 22, the image adjustment processing unit 23, the target chromaticity calculation processing unit 24, and the color correction, which are components of the color correction processing device 5. Although it is assumed that each of the coefficient calculation processing unit 25 and the color correction processing unit 26 is configured by dedicated hardware, when the color correction processing device 5 is configured by a computer, a color correction image display unit. 21, DSCs 12 a and 12 b, image acquisition processing unit 22, image adjustment processing unit 23, target chromaticity calculation processing unit 24, color correction coefficient calculation processing unit 25 and color correction processing unit 26. The CPU of the computer may execute the program stored in the memory.

Next, the operation will be described.
The color correction image display unit 21 of the color correction processing device 5 displays the image for color correction on the two display panels D1 and D2 constituting the multi-display 1a, and constitutes the multi-display 1b. An image for color correction is displayed on the two display panels D3 and D4.
In other words, the color correction image display unit 21 applies R (red), G to the display panels D1 to D4 constituting the multi-displays 1a and 1b, similarly to the color correction image display unit 11 of FIG. A monochrome image of (green) and B (blue) and an image of W (white) and Bk (black) are displayed simultaneously.
When the color correction image display unit 21 displays the color correction image on the display panels D <b> 1 to D <b> 4, the color correction image display unit 21 outputs a signal indicating completion of display of the color correction image to the image acquisition processing unit 22.

Upon receiving a signal indicating completion of display of the color correction image from the color correction image display unit 21, the image acquisition processing unit 22 outputs an image capturing command to the DSCs 12a and 12b.
When the DSC 12a (DSC 12b) receives an image capturing command from the image acquisition processing unit 22, the DSC 12a (DSC 12b) captures the image for color correction displayed on the display panels D1, D2 (D3, D4), and RAW which is the captured image. RAW image data indicating an image is output to the image acquisition processing unit 22.
At this time, the shooting position of the DSC 12a (DSC 12b) is adjusted so that the entire display image of the two display panels D1, D2 (D3, D4) is within the shooting range of the DSC 12a (DSC 12b). To do. Alternatively, it is assumed that the lens is adjusted using a telephoto or wide-angle lens so as to be within the photographing range of the DSC 12a (DSC 12b).
Further, the shutter speed and aperture of the DSC 12a (DSC 12b) are adjusted according to the purpose, and when correcting the display panels D1, D2 (D3, D4), they are adjusted slightly blurred by the telephoto lens.
The image acquisition processing unit 22 acquires RAW image data indicating a RAW image output from the DSCs 12a and 12b.

  When the image acquisition processing unit 22 acquires RAW image data indicating a RAW image, the image adjustment processing unit 23 performs white adjustment of the RAW image as an image adjustment process for the RAW image, as in the image adjustment processing unit 14 of FIG. Adjust the balance.

When the image adjustment processing unit 23 adjusts the white balance of the RAW image, the target chromaticity calculation processing unit 24 represents the target color reproduction characteristics of the two display panels D1 and D2 from the RAW image after the white balance adjustment processing. The target chromaticity which is chromaticity is calculated, and the target chromaticity which is chromaticity representing the target color reproduction characteristics in the two display panels D3 and D4 is calculated.
Since the target chromaticity calculation processing by the target chromaticity calculation processing unit 24 is the same as the target chromaticity calculation processing by the target chromaticity calculation processing unit 15 in FIG. 1, detailed description thereof is omitted.
However, in the example of FIG. 7, the target chromaticity of the display panels D1 and D2 is calculated by obtaining a common area of the color gamut of the display panel D1 and the color gamut of the display panel D2, and the display panel D3 The target chromaticity of the display panels D3 and D4 is calculated by obtaining a common area between the color reproduction area and the color reproduction area of the display panel D4.

When the target chromaticity calculation processing unit 24 calculates the target chromaticity, the color correction coefficient calculation processing unit 25 calculates the target chromaticity of the display panels D1 and D2 in the same manner as the color correction coefficient calculation processing unit 16 of FIG. A color correction matrix coefficient is calculated as a color correction coefficient from the chromaticities of the display panels D1 and D2.
Further, a color correction matrix coefficient is calculated as a color correction coefficient from the target chromaticity of the display panels D3 and D4 and the chromaticity of the display panels D3 and D4.
However, the color correction matrix coefficient is calculated for each of the display panels D1 to D4.

  When the color correction coefficient calculation processing unit 25 calculates the color correction matrix coefficient, the color correction processing unit 26 uses the color correction matrix coefficient to display the display panels D1 to D1, as in the color correction processing unit 17 of FIG. D4 color correction processing (matrix calculation for color correction) is performed.

  As is apparent from the above, according to the fourth embodiment, when a plurality of multi-displays 1a and 1b are installed, the color correction image display unit 21 sets the multi-display for each of the multi-displays 1a and 1b. An image for color correction is displayed on the configured display panels D1, D2 (D3, D4), and the image acquisition processing unit 22 configures the display panels D1, D2 (D3, D4) constituting the multi-display. Since the image for color correction displayed on the screen is captured and the captured image is acquired, for example, even when multiple multi-displays are installed as in a digital signage system, There is an effect that a color shift between a plurality of display panels constituting the display can be corrected with high accuracy.

In the fourth embodiment, for each of the multi-displays 1a and 1b, correction of color misregistration between the display panels D1 and D2 (or D3 and D4) constituting the multi-display is shown. You may make it correct | amend the color shift between display panels D1-D4 by calculating | requiring the common area | region of the color reproduction area in display panels D1-D4.
In this case, color correction of the display panels D1 to D4 is performed by calculating the target chromaticity according to the procedure according to the first embodiment.

  In the present invention, within the scope of the invention, any combination of the embodiments, or any modification of any component in each embodiment, or omission of any component in each embodiment is possible. .

  1, 1a, 1b Multi-display, D0 to D8 display panel, 2, 4 image display device, 3, 5 color correction processing device, 11, 21 color correction image display unit (color correction image display means), 12, 12a , 12b DSC (captured image acquisition unit), 13, 22 image acquisition processing unit (captured image acquisition unit), 14, 23 image adjustment processing unit (image adjustment processing unit), 15, 24 target chromaticity calculation processing unit (target color) Degree calculation means), 16, 25 color correction coefficient calculation processing section (color correction coefficient calculation means), 26, 17 color correction processing section (color correction means).

Claims (5)

Color correction image display means for displaying color correction images on a plurality of display panels constituting a multi-display;
Captured image acquisition means for capturing an image for color correction displayed on the plurality of display panels and acquiring the captured image;
Image adjustment processing means for performing image adjustment processing on the captured image acquired by the captured image acquisition means;
Target chromaticity calculation means for calculating target chromaticity, which is chromaticity representing target color reproduction characteristics in the plurality of display panels, from a captured image after image adjustment processing by the image adjustment processing means;
Color correction coefficient calculating means for calculating a color correction coefficient from the target chromaticity calculated by the target chromaticity calculating means and the chromaticities of the plurality of display panels;
Color correction means for performing color correction of the plurality of display panels using the color correction coefficient calculated by the color correction coefficient calculation means ,
When calculating the target chromaticity in the plurality of display panels, the target chromaticity calculation means sets, for each of the plurality of display panels, the filter coefficient used for noise removal in the peripheral display panel. A color correction processing apparatus , characterized in that a target chromaticity is obtained by multiplying a value indicating a target chromaticity of a display panel arranged and summing the values . If multiple multi-display is provided, the color correction image display means for each multi-display, and displays an image for color correction for a plurality of display panels constituting the multi-display,
2. The color according to claim 1, wherein the captured image acquisition unit captures images for color correction displayed on a plurality of display panels constituting the multi-display, and acquires the captured images. Correction processing device. The image adjustment processing means, as the image adjustment processing for the captured image acquired by the captured image acquisition unit, the color correction process according to claim 1 or claim 2, wherein the adjusting the white balance of the captured image apparatus. A color correction image display means for displaying a color correction image on a plurality of display panels in which the color correction image display means constitutes a multi-display; and
Captured image acquisition processing step in which captured image acquisition means captures the image for color correction displayed on the plurality of display panels and acquires the captured image;
An image adjustment processing step in which image adjustment processing means performs image adjustment processing on the captured image acquired in the captured image acquisition processing step;
Target chromaticity calculation processing step in which the target chromaticity calculation means calculates a target chromaticity that is a chromaticity representing target color reproduction characteristics in the plurality of display panels from the captured image after the image adjustment processing in the image adjustment processing step. When,
A color correction coefficient calculation processing step in which a color correction coefficient calculation means calculates a color correction coefficient from the target chromaticity calculated in the target chromaticity calculation processing step and the chromaticity of the plurality of display panels;
A color correction processing step for performing color correction of the plurality of display panels using the color correction coefficient calculated in the color correction coefficient calculation processing step ;
In the target chromaticity calculation processing step, when calculating the target chromaticity in a plurality of display panels, the filter coefficient used for noise removal in the display panel arranged in the periphery is calculated for each of the plurality of display panels. A color correction processing method characterized in that a target chromaticity is obtained by multiplying a value indicating the target chromaticity of the display panel arranged in the display panel and summing the values . In a multi-display device comprising: an image display device that displays an image on a plurality of display panels constituting a multi-display; and a color correction processing device that corrects a color shift between the plurality of display panels.
The color correction processing device photographs color correction image display means for displaying color correction images on the plurality of display panels, and color correction images displayed on the plurality of display panels. A captured image acquisition unit that acquires the captured image, an image adjustment processing unit that performs image adjustment processing on the captured image acquired by the captured image acquisition unit, and a captured image that has been subjected to image adjustment processing by the image adjustment processing unit. , Target chromaticity calculation means for calculating target chromaticity that is chromaticity representing target color reproduction characteristics in the plurality of display panels, target chromaticity calculated by the target chromaticity calculation means, and the plurality of display panels The color correction coefficient calculating means for calculating the color correction coefficient from the chromaticity of the color and the color correction coefficient calculated by the color correction coefficient calculating means And a color correction unit for performing color correction of the spray panel,
When the target chromaticity calculation means calculates the target chromaticity in the plurality of display panels, the filter coefficient used for noise removal in the display panel arranged in the periphery is set in the periphery for each of the plurality of display panels. A multi-display device characterized in that a target chromaticity is obtained by multiplying a value indicating a target chromaticity of a display panel arranged and summing the values .

Images