JP2002238064A - Large screen display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a large screen display device that can smoothly display joints of pictures, even if there luminance differences exist among projection display devices. SOLUTION: Identical transformation function is set to edge blend boards E1, E2, E3, an image is projected sequentially from projectors P1, P2, P3 one by one, a camera C1 or C2 photographs an image onto a screen S, while sequentially changing the luminance (n) of outputs of graphics boards G1, G2, G3, each measured value is obtained as a luminance sensitivity characteristics of the projector P1 and the camera C1, a luminance sensitivity characteristics of the projector P2 and the camera C1, and a luminance sensitivity characteristics of the projector P3 and the camera C2, a luminance correction value is obtained to correct differences of luminance among the projectors P1-P3 to zero, on the basis of each luminance sensitivity characteristics the reference luminance conversion function is corrected in accordance with the luminance correction value to set the luminance conversion function specific to the edge blend boards E1-E3, the images whose luminance is corrected according to the luminance conversion function are displayed, while being continuously laid out on the screen S to smoothly display the joints of the images.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a large-screen display device, and more particularly, to an image obtained by dividing an original image into a plurality of images and projecting the images onto a screen by a plurality of projection-type displays. The present invention relates to a large-screen display device suitable for displaying images side by side.

[0002]

2. Description of the Related Art Conventionally, as a large-screen display device using a plurality of projection displays, for example, Japanese Unexamined Patent Application Publication No. 11-984
The one described in JP-A-39 is known. In a large-screen display device of this type, when displaying a plurality of images side by side on a screen, in order to smoothly display the seam of each image, an overlap region is provided between the images, and the luminance in the overlap region is set. An edge blending method is adopted in which an image is gradually darkened from an overlap start point indicating a boundary between each image and an overlap area toward an overlap end point indicating an end of each image.

[0003]

In the prior art,
When adopting the edge blending method, a method is used in which an image on the screen is photographed by one camera and the luminance in the overlap region is adjusted according to a video signal obtained by photographing with this camera. No consideration is given to correcting the brightness based on the difference in brightness between the projection displays, and when there is a difference in brightness between each projection display (projector), the seam of each image should be displayed smoothly. Can not.

[0004] It is an object of the present invention to provide a large-screen display device capable of smoothly displaying a joint of images even if a difference in luminance occurs between projection-type displays.

[0005]

In order to solve the above-mentioned problems, the present invention relates to an image obtained by dividing an original image, wherein the plurality of images have an overlap area between adjacent images. A plurality of image signal generating means for outputting, for each image, an image signal including the luminance and coordinates of each pixel as information; and a luminance conversion function corresponding to each of the images, the luminance of the image signal generated by the plurality of image signal generating means. A plurality of brightness conversion means for converting and outputting an image signal whose brightness has been converted, and projecting an image in accordance with the image signal from the plurality of brightness conversion means toward a screen to continuously form each image on the screen. A plurality of projection displays that are arranged and displayed in parallel, a camera that captures an image on the screen to generate a video signal, and a luminance conversion unit based on the video signal generated by the camera. Brightness conversion function calculation means for calculating a unique brightness conversion function; and brightness conversion corrected by correcting the brightness of an image belonging to the overlap area of each image among the brightness conversion functions calculated by the brightness conversion function calculation means. Brightness conversion function correction means for setting a function to each of the brightness conversion means as a brightness conversion function at the time of large-screen display, wherein the brightness conversion function calculation means, as a brightness conversion function at the time of function calculation, to each of the brightness conversion means Using a reference luminance conversion function, and correcting a difference in luminance between the projection displays to zero based on a video signal when an image obtained by projection of each projection display alone is shot by the camera. Of a large-screen display device that calculates a luminance conversion function for the display.

In constructing the large-screen display device, instead of a single camera, a plurality of cameras for generating an image signal by capturing an image on a screen by dividing the image on the screen into a plurality of images are used. The calculation means may be configured to have a function of calculating a brightness conversion function unique to each brightness conversion means based on a video signal generated by each camera.

The following elements can be added when configuring each of the large-screen display devices.

(1) The brightness conversion function calculation means calculates a sensitivity between the cameras based on a video signal obtained when each of the cameras captures a common image obtained by projection from any one of the projection displays. The sensitivity correction function for correcting the difference between the two to zero is calculated, and the video signal at the time of calculating the luminance correction value is corrected according to the calculated sensitivity correction function.

(2) The brightness conversion function of the brightness conversion means used when calculating the sensitivity correction function is an identity conversion function in which the input brightness and the output brightness are equal.

(3) The reference luminance conversion function is an identity conversion function in which the input luminance and the output luminance are equal.

(4) The luminance function correcting means indicates the luminance of an image belonging to the overlap area of each image among the luminance conversion functions corresponding to each image, and indicates a boundary between each image and the overlap area. The correction is made gradually darker from the overlap start point toward the overlap end point indicating the end of each image.

According to the above-mentioned means, prior to displaying a plurality of images continuously on the screen, the reference brightness conversion function is used for each brightness conversion means, and each projection type display is obtained by projection alone. A brightness correction value is calculated based on a video signal obtained when each of the captured images is photographed by a camera, and a reference brightness conversion function is corrected according to each calculated brightness correction value to obtain a brightness conversion function unique to each brightness conversion unit. Calculates and sets the brightness conversion function at the time of large screen display based on the calculated brightness conversion function, so even if there is a difference in brightness between projection type displays, the seam of each image is displayed smoothly can do.

In calculating the luminance correction value, a sensitivity correction function is calculated based on a video signal obtained when each of the common images obtained by the projection of one of the projection displays is photographed by a camera. Since the video signal at the time of calculating the brightness correction value is corrected in accordance with the sensitivity correction function, even if the brightness differs between the cameras due to the individual differences of the imaging devices constituting the cameras, etc., the individual differences between the cameras may differ. And the sensitivity between the cameras can be corrected to an appropriate value.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an overall configuration diagram of a large-screen display device according to a first embodiment of the present invention. In FIG.
The large screen display device is a personal computer (PC) 10
The personal computer includes a calculation processing unit 12 having a CPU, a memory, etc., graphics boards G1, G2, G3, edge blend boards E1, E
2 and E3, and each unit is connected via a system bus 14.

Graphics boards G1, G2, G3
Is an image obtained by dividing the original image into three, and as information relating to a plurality of images having an overlap area between adjacent images, a digital image including luminance and coordinates of pixels constituting each image. It is configured as image signal generating means for outputting a signal to the edge blend boards E1, E2, E3 for each image.

The edge blend boards E1, E2, and E3 receive digital image signals from the graphics boards G1, G2, and G3, respectively, and convert the luminance of the image signals according to a luminance conversion function corresponding to each image. The converted image signals are supplied to projectors P1 and P1, respectively.
2. It is configured as a luminance conversion means for outputting to P3.

Specifically, the edge blend board E1,
E2 and E3 are a digital input interface 20, an address converter 22, a luminance conversion function memory (RAM) 24, and a digital output interface 2 as shown in FIG.
6, a system bus interface 28, a digital input interface 20 is connected to each of the graphics boards G1, G2, G3, and a digital output interface 26 is
1, P2, P3, and the system bus interface 28 is connected to the calculation processing unit 12 via the system bus 14. The digital input interface 20 captures a digital image signal, decodes the current coordinates and luminance of the information contained in the input digital image signal, and outputs the decoded digital signal to the address converter 22. It has become. The address converter 22 converts coordinates indicating the position of each pixel into an address of a memory, and stores data relating to luminance in the luminance conversion function memory 24 according to the converted address.

The brightness conversion function memory 24 includes, for example,
The RAM is composed of (number of screen pixels) × (number of gradations of input signal). The number of input pixels is 640 dots horizontally and 480 dots vertically, the number of gradations of input signal is 256, and the number of bits of output signal is In the case of 8 bits, the RAM has a size of 640 × 480 × 256 bytes. The luminance conversion function memory 24 stores data relating to an image signal whose luminance has been converted in accordance with the luminance conversion function, and among the stored data, relating to the luminance of an image belonging to the overlap area of each image. The data is corrected by the calculation processing unit 12 which accesses the memory 24 via the system bus interface 28 when displaying a large screen. Further, in the brightness conversion function memory 24, a reference brightness conversion function and a brightness conversion function for displaying a large screen are set from the calculation processing unit 12 via the system bus interface 28.

Each of the projectors P1, P2, P3 is connected to each of the edge blend boards E1, E2, E3 as an element of the projection type display and connected to the calculation processing unit 12 via the system bus 14. I have.
Each of the projectors P1, P2, and P3 receives a digital image signal from each of the edge blend boards E1, E2, and E3, projects an image according to each of the image signals toward the screen S, and continuously displays each image on the screen S. Are displayed side by side. In this case, the projector P
1, overlap area O between images projected by P2
1 is displayed, and the projectors P2, P3
The image corresponding to the overlap area O2 is displayed between the images projected by the above.

Each image displayed on the screen S is photographed by two cameras C1 and C2, and a video signal generated by photographing by each camera C1 and C2 is transferred to the calculation processing unit 12 via the system bus 14. It is supposed to be.
Each of the cameras C1 and C2 is configured using, for example, an image sensor, and each of the cameras C1 and C2 outputs a video signal corresponding to the luminance of an image on the screen S.

The calculation processing unit 12 controls each edge blend board E based on the video signal generated by each of the cameras C1 and C2.
1, E2, and E3 are configured as a luminance conversion function calculation unit that calculates a specific luminance conversion function, and corrects the luminance of an image belonging to the overlap region of each image among the calculated luminance conversion functions. The brightness conversion function is configured as a brightness conversion function correction unit that sets the obtained brightness conversion function in the edge blend boards E1, E2, and E3 as a brightness conversion function when displaying a large screen.

As the luminance conversion function, for example, FIG.
(A), the or set luminance conversion function F and the input luminance and output luminance changes in a curved line, as shown in FIG. 3 (b), is an input luminance n ₁ and output luminance n ₀ An identity conversion function that sets the same value is set.

The function of the personal computer 10 will be described below with reference to the flowchart of FIG. Prior to displaying a large screen on the screen S, the personal computer 10 performs processing for correcting the sensitivity between the cameras C1 and C2 (step 31), and then performs luminance processing on each of the edge blend boards E1, E2, and E3. A process for calculating a conversion function is performed (step 32), and a process for correcting the brightness of the overlap region (edge blending unit) in the calculated brightness conversion function is performed (step 33). The specific processing contents in step 31 will be described with reference to FIGS.

First, each of the edge blend boards E1 to E3
Of the edge blend boards E1 to E
3 is set to an identity conversion function that makes the input luminance and the output luminance the same (step 101), and the calculation processing unit 12 sets the luminance sensitivity characteristic array c ₁ [n] (n is an integer of 0 to 255, and the size is 1 byte each), luminance sensitivity characteristic array c ₂ [n] (n = 0)
An integer of ~ 255 and a size of 1 byte each are prepared (step 102), and a variable n is initialized to 0 (step 10).
3).

Next, the cameras C1 and C2 capture a common image common to the cameras, and each of the cameras C1 and C2 detects a change in luminance of each common image. In this case, while taking an image from the projector P2, the input brightness of the edge blend board E2 is sequentially changed according to the identity conversion function, and the image of the brightness n according to the identity conversion function is displayed on the screen S by the projector P2. (Step 104). At this time, the brightness obtained by shooting with the camera C1 is set to c ₁ [n] (step 105), and the brightness obtained by shooting with the camera C2 is set to c ₂ [n] (step 10).
6) The input luminance is sequentially increased (step 107), and the same processing is performed until the input luminance changes 256 gradations from 0 to 255 (step 108). The measured luminance of the camera C1 is shown in FIG. Such a characteristic is obtained, and a characteristic as shown in FIG. 5B is obtained as a measurement of the camera C2.

FIG. 5A shows the relationship between the luminance input n of the projector P2 and the output of the camera C1, and FIG.
Shows the relationship between the input luminance n of the projector P2 and the output of the camera C2.

In the characteristics shown in FIGS. 5A and 5B, the horizontal axis represents the luminance input n of the projector P2, and the vertical axis represents the measured values of the cameras C1 and C2. 0
To a maximum value (255), it is possible to calculate a sensitivity correction function for correcting the difference in sensitivity between the cameras to zero.

For example, when input luminance n = N, FIG.
(A) N = _{c 1} becomes a characteristic shown in, consists of characteristic shown in FIG. 5 (b) and N = _{c 2.} Here, a relational expression for equalizing the two is derived. As shown in (c), a sensitivity correction function c ₂ = for correcting the difference in sensitivity between the cameras to zero is obtained.
e ₂₁ (c ₁ ) can be obtained. This sensitivity correction function indicates the relative sensitivity of the camera C1 and the camera C2 at the same luminance.

When obtaining the sensitivity correction function, FIG.
As shown in (a), the measured value c ₁ [n] of the camera C1 is set on the horizontal axis, and the measured value c ₂ [n] of the camera C2 is set on the vertical axis.
When n is plotted while changing n from 0 to 255, FIG.
The measured values shown in (a) are discrete values.

By linearly interpolating the measured values, FIG.
Sensitivity correction function c with characteristics as shown in ₂= E₂₁(C₁)
Can be requested. The measured values shown in FIG.
Indicates the measured value c of the camera C1 on the horizontal axis.₁, Measurement of the vertical axis camera C2
Constant value c₂Indicates the value reset.

Next, each of the edge blend boards E1 to E3
Step 3 as a process for calculating the brightness conversion function of
2 (FIG. 4) is executed. In this case, in the present embodiment, since the brightness of the other projectors P2 and P3 is converted by the edge blend boards E2 and E3 using the brightness of the projector P1 as the reference brightness characteristic, a method is adopted.
As a brightness conversion function of the edge blend board E1, for example, an identity conversion function (reference brightness conversion function) in which the input brightness is equal to the output brightness is set in the edge blend board E1.
Then, the projectors P2 and P3 other than the projector P1
The projection by stops, changing the luminance by the output of the graphics board G1 n, the image by the projection of only the projector P1 measured by the camera C1, and the measured values c _1, a n from 0 to the maximum value (255) Then, as shown in FIG. 8, the luminance sensitivity characteristic c of the projector P1 and the camera C1
₁ = R ₁₁ (n) is obtained.

Similarly, an identity conversion function is set as a brightness conversion function of the edge blend board E2, only the projector P2 is projected, the brightness by the output of the graphics board G2 is set to n, and the image by the projection of the projector P2 is set to n. was measured by the camera C1, and the measured value and c _2,
By changing n from 0 to the maximum value (255), as shown in FIG. 8, the brightness sensitivity characteristics c ₁ = R ₁₂ (n) of the projector P2 and the camera C1 are set as a brightness conversion function F2 unique to the edge blend board E2. Ask.

That is, a luminance sensitivity characteristic for correcting a luminance difference between the projectors P1 and P2 to zero is calculated based on a video signal obtained by photographing with the camera C1.

Hereinafter, specific contents will be described.

First, when measuring the luminance sensitivity characteristics of the projector P1 and the camera C1, as shown in FIG.
The brightness value of the edge blend board E1 is initialized (step 121), and an identity conversion function is set for the edge blend board E1 as a brightness conversion function that makes the input brightness and the output brightness the same, and the brightness sensitivity characteristic array R
₁₁ [n] (where n is an integer from 0 to 255 and the size is 1 byte) is prepared (step 122). Thereafter, the variable n is initialized (step 123), and the graphics board G is initialized.
Assuming that the luminance of the image signal resulting from the output of 1 is n, the image signal having the luminance n is output to the projector P1 via the edge blend board E1, and the camera C1 detects an image projected by the projector P1 (steps 124 and 125). In this case, since the brightness conversion function set in the edge blend board E1 is an identity conversion function, the output brightness of the edge blend board E1 and the input brightness of the projector P1 are equal to n.
Becomes Then, the image obtained by the projection by the projector P1 is measured by the camera C1, and the luminance sensitivity characteristic array R ₁₁ [n] obtained by the measurement by the camera C1 is stored. Thereafter, 1 is added to n, the same processing is continued, and the measured value of the camera C1 is obtained until n exceeds 255 (steps 126 and 127).

FIG. 10A shows the measurement result at this time. The measured values shown in FIG.
₁₁ [n] is a vertical axis, and is a value when plotting while changing n from 0 to 255, which is a discrete value. When this measurement value is linearly interpolated, as shown in FIG.
Luminance sensitivity characteristic c ₁ = R of projector 1 and camera C1
₁₁ (n) can be obtained.

Next, when the luminance sensitivity characteristics of the projector P2 and the camera C1 are obtained, the edge blend board E2 is initialized in the same manner as in the case of obtaining the luminance sensitivity characteristics of the projector P1 and the camera C1. As shown in the figure, the calculation processing unit 11 controls the brightness sensitivity characteristic array R12 [n].
(N = 0 to 255 integer, size each 1 byte) prepared (step 141), the variable _{n 1} is initialized to 0 (step 142), the luminance _{n 1} from the edge blend board E2
Is output to the projector P2, an image projected by the projector P2 is measured by the camera C1, and the measured value is stored as a luminance sensitivity characteristic array R ₁₂ [n1]. In this case, the output value n of the graphics board G2
_1, in order to convert the reference luminance characteristic using the edge blending board E2, when the graphics board G2 output n = n _1, that measured value of the camera C1 may be such that c ₁ Become. That is, c ₁ = R ₁₁ (n
₁ ), c ₁ = R ₁₂ (n), and R ₁₁ (n ₁ ) = R
₁₂ (n ₂ ). As a result, n ₂ = R ₁₂ ⁻¹ (R
₁₁ [n]).

The maximum value After this, the _{n 1} from 0 (255)
And the relationship between n ₁ and n ₂ is calculated sequentially (steps 144 and 145), and the projector P2 and camera C1 are calculated.
Can be obtained as a luminance conversion function F2 unique to the edge blend board E2.

Next, the brightness unique to the edge blend board E3
When calculating the degree conversion function F3, the projector P
3 and camera C2, projector P3 and camera C2
Luminance sensitivity characteristic c₂= R₂₃(N) is generated. Sand
The input of the edge blend board E3 is n₁, Reference brightness
Edge blend converted to characteristics (reference brightness conversion function)
Output of board E3 is n₃Then, from the reference luminance characteristics,
c₁= R₁₁(N₁) Is required and the camera C
1 and sensitivity correction function c of camera C2₂= E₂₁(C₁),
Luminance sensitivity characteristic c of projector P3 and camera C2₂= R
₂₃(N₃) From e₂₁(R₁₁[N]) = R
₂₃(N₃) Is obtained, and n₃= R₂₃ ^-1(E ₂₁[R
₁₁(N₁)]).

[0040] In obtaining the luminance conversion function F3 of the edge blending board E3, as shown in FIG. _{13, R 23}
[N] to the prepared (step 151), the output value _{n 1} of the graphics board G3 to 0 (step 152), measuring the image by the imaging projector P3 camera C2, the measurement value _R ^{23 -1} ( e ₂₁ [R
₁₁ (n ₁ )]), the brightness n ₁ is sequentially increased by one, and the same processing is performed until n ₁ exceeds 255 (steps 153, 154, 155), and the brightness conversion function F3 of the edge blend board E3 is performed. Is calculated.

Thereafter, as the processing of step 33 (FIG. 4), the luminance of the image belonging to the overlap area of each image is determined by the overlap start point indicating the boundary between each image and the overlap area and the overlap indicating the end of each image. Correction is performed to gradually lower the brightness toward the end point, and the brightness conversion function of the pixel (dot) corresponding to the overlap area (edge blending section) is corrected.

More specifically, as shown in FIG. 14, an ideal characteristic set by a luminance conversion function is set to an overlap area where each image overlaps among images projected by each of the projectors P1, P2, and P3. Are sequentially reduced from 1 to 0 as going from the overlap start point to the overlap end point. Here, m1, m2, and m3 indicate the magnification of the ideal characteristic, and x1, x2, and x3 indicate the x coordinates of each image.

For the dots (pixels) corresponding to the overlap area (edge blending section) in the images of the edge blend boards E1 to E3, the magnification specified by the x coordinate is multiplied by the ideal characteristic, and this multiplication is performed. Then, the brightness conversion functions of the edge blend boards E1 to E3 are corrected based on the ideal characteristics, and set as the brightness conversion functions in the large-screen display for the edge blend boards E1 to E3.

When displaying the images side by side on the screen S, as shown in FIG. 15, the original image G0 is divided into three parts to cut out the images 1, 2 and 3, and the image signals relating to the images 1 to 3 are obtained. When output from the graphics boards G1 to G3 to the edge blend boards E1 to E3, each image signal is corrected according to a luminance conversion function unique to each of the edge blend boards E1 to E3, and the corrected image signals are output to the projectors P1 to P3. And each projector P1
To P3 are displayed side by side on the screen S.

In this case, in this embodiment, since the difference in luminance between the projectors P1 to P3 is corrected,
Even if there is a difference in brightness between the projectors, the seam of each image can be displayed smoothly. Furthermore, since individual differences between cameras are corrected according to the sensitivity correction function,
Even if there is an individual difference between the cameras C1 and C2, the seam of each image can be displayed smoothly.

Next, a second embodiment of the present invention will be described with reference to FIG. In the present embodiment, the screen S is widened horizontally and one camera is added (camera C3).
Graphics board G4, Edge blend board E
4. A projector P4 is added, and the other configuration is the same as that of FIG.

In the present embodiment, the sensitivity correction function c ₃ = e ₃₂ (c ₂ ) of the cameras C2 and C3, and the luminance sensitivity characteristic c ₃ = R of the projector P4 and the camera C3.
₃₄ (n ₄ ), and at this time, e ₃₂ (e ₂₁ [R
₁₁ (n ₁ )]) = R ₃₄ (n ₄ ), so that n ₄ = R ₃₄ ⁻¹ (e ₃₂ [e ₂₁ (R
₁₁ [n ₁ ])]). From this relationship, the brightness conversion function of the edge blend board E4 can be calculated.

As described above, according to the present embodiment, as in the previous embodiment, since the difference in luminance between the projectors P1 to P4 is corrected, even if there is a difference in brightness between the projectors, The seam of each image can be displayed smoothly. Furthermore, since the individual differences between the cameras are corrected according to the sensitivity correction function, even if there are individual differences between the cameras C1, C2, and C3, the seam of each image can be displayed smoothly.

Further, in the present invention, since a plurality of cameras are used to correct an image, a plurality of images are displayed side by side on various screens such as a free screen such as a spherical screen and a huge screen. Even in this case, the seam of each image can be displayed smoothly.

[0050]

As described above, according to the present invention,
Even if there is a difference in brightness between the projection displays, the seam of each image can be displayed smoothly, which can contribute to the improvement of the quality of the displayed image.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a large-screen display device according to a first embodiment of the present invention.

FIG. 2 is a block diagram of an edge blend board.

FIGS. 3A and 3B are explanatory diagrams for explaining a brightness conversion function of an edge blend board. FIGS.

FIG. 4 is a flowchart for explaining the operation of the device shown in FIG. 1;

FIGS. 5A, 5B, and 5C are diagrams for explaining sensitivity characteristics of the cameras C1 and C2.

FIG. 6 is a flowchart for explaining a sensitivity characteristic calculation method of the cameras C1 and C2.

FIGS. 7A and 7B are diagrams for explaining a method of calculating a sensitivity correction function.

FIG. 8 is a diagram for explaining a method of calculating a luminance conversion function of the edge blend board E1 and the edge blend board E2.

FIG. 9 is a flowchart for explaining a method of measuring the luminance sensitivity characteristics of the projector P1 and the camera C1.

FIGS. 10A and 10B are diagrams for explaining a method of generating a luminance sensitivity characteristic from a luminance sensitivity characteristic array.

FIG. 11 is a diagram for explaining a method of calculating a luminance conversion function of the edge blend board E2.

FIG. 12 is a diagram for explaining a method of calculating a luminance conversion function of the edge blend board E3.

FIG. 13 is a flowchart illustrating a method for calculating a luminance conversion function of the edge blend board E3.

FIG. 14 is a diagram for explaining a method of correcting a brightness conversion function of a dot corresponding to an edge blend unit of an edge blend board.

FIG. 15 is a diagram illustrating a method of dividing an original image into a plurality of images.

FIG. 16 is an overall configuration diagram showing a second embodiment of the large screen display device according to the present invention.

[Explanation of symbols]

 Reference Signs List 10 personal computer 12 calculation processing unit 14 system bus G1 to G3 graphics board E1 to E3 edge blend board P1 to P3 projector S screen C1, C2 camera

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G09G 5/00 550 G09G 5/00 550C 5/10 5/10 Z H04N 5/74 H04N 5/74 D ( 72) Inventor Kenji Ando 5-2-1 Omika-cho, Hitachi City, Ibaraki Prefecture Within the Information Control Systems Division, Hitachi, Ltd. (72) Inventor Masaki Ishikawa 5-2-1 Omika-cho, Hitachi City, Ibaraki Prefecture 5C058 BA05 BB25 EA01 EA32 5C061 BB15 CC05 EE05 5C080 CC06 CC10 DD05 EE28 JJ01 JJ02 JJ05 JJ07 5C082 AA34 BD07 CA11 CA85 CB03 MM10

Claims (6)

[Claims] 1. An image signal which is obtained by dividing an original image and includes luminance and coordinates of each pixel as information on a plurality of images having an overlap area between adjacent images. A plurality of image signal generating means for outputting, and a plurality of luminances for converting the luminance of the image signal generated by the plurality of image signal generating means according to a luminance conversion function corresponding to each of the images and outputting an image signal whose luminance is converted Conversion means, a plurality of projection displays for projecting an image according to image signals from the plurality of luminance conversion means toward a screen and displaying each image continuously on the screen and displaying the images, A camera that captures an image to generate a video signal, and a brightness conversion function calculation unit that calculates a brightness conversion function unique to each brightness conversion unit based on the video signal generated by the camera. The luminance conversion function calculated by the luminance conversion function calculation means, which corrects the luminance of an image belonging to the overlapping area of each image, and uses the corrected luminance conversion function as a luminance conversion function when displaying a large screen. Brightness conversion function correction means for setting the conversion means, wherein the brightness conversion function calculation means uses a reference brightness conversion function for each of the brightness conversion means as a brightness conversion function at the time of function calculation, and each of the projection type displays alone Large-screen display device that calculates a brightness conversion function for correcting a brightness difference between the projection-type displays to zero based on a video signal when an image obtained by the projection is captured by the camera. . 2. An image signal obtained by dividing an original image and including an image signal including luminance and coordinates of each pixel as information on a plurality of images having an overlapping area between adjacent images. A plurality of image signal generating means for outputting, and a plurality of luminances for converting the luminance of the image signal generated by the plurality of image signal generating means according to a luminance conversion function corresponding to each of the images and outputting an image signal whose luminance is converted Conversion means, a plurality of projection displays for projecting an image according to image signals from the plurality of luminance conversion means toward a screen and displaying each image continuously on the screen and displaying the images, A plurality of cameras that generate a video signal by shooting an image by dividing the image into a plurality of images, and calculate a brightness conversion function unique to each brightness conversion unit based on the video signal generated by each camera. Brightness conversion function calculating means,
The luminance conversion functions calculated by the luminance conversion function calculation means are used to correct the luminance of the image belonging to the overlap area of each image, and the corrected luminance conversion function is used as the luminance conversion function when displaying a large screen. Brightness conversion function correction means to set the means, the brightness conversion function calculation means, using a reference brightness conversion function for each brightness conversion means as a brightness conversion function at the time of function calculation, and for each projection type display alone A large screen obtained by calculating a luminance conversion function for correcting a difference in luminance between the projection-type displays to zero based on a video signal when an image obtained by projection is captured by any one of the cameras. Display device. 3. The large-screen display device according to claim 2, wherein the brightness conversion function calculating unit is configured to execute a process when each of the cameras captures a common image obtained by projection of any one of the projection displays. Calculating a sensitivity correction function for correcting a difference in sensitivity between the cameras to zero based on a video signal, and correcting the video signal at the time of calculating the luminance correction value according to the calculated sensitivity correction function. A large-screen display device characterized by the above-mentioned. 4. The large-screen display device according to claim 3, wherein the brightness conversion function of the brightness conversion means used when calculating the sensitivity correction function is an identity conversion function in which the input brightness and the output brightness are equal. A large-screen display device characterized by the above-mentioned. 5. The large-screen display device according to claim 1, wherein the reference luminance conversion function is an identity conversion in which input luminance is equal to output luminance. A large-screen display device, which is a function. 6. The large-screen display device according to claim 1, wherein the brightness function correction unit includes a brightness conversion function corresponding to each of the images. The brightness of the images belonging to the overlap area of each image is gradually darkened from the overlap start point indicating the boundary between each image and the overlap area toward the overlap end point indicating the end of each image. A large-screen display device, characterized in that: