JP2020031291A - Projection system - Google Patents

Abstract

To reduce a trouble of a user who previously installs a camera at an appropriate position in determining a camera exposure value suitable for a projected image.SOLUTION: The projection system includes: a plurality of projectors; a camera capable of imaging a projection plane to which the projectors project; and one or more control units for controlling the projectors and the camera. The control units are configured to obtain brightness of a predetermined area by the camera for the projectors of the number of the projectors in a state where a pattern is projected only by one of the projectors and determine exposure time of the camera on the basis of a value between the maximum and the minimum of the obtained brightness of the projectors.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a projection system that controls projection of a plurality of projectors.

  A multi-projection method using a plurality of projectors has been known in order to increase the resolution and the size of a projection screen. Multi-projection is a method of connecting projection screens of a plurality of projectors to display one screen. In addition, there is known a method called stack projection for achieving high luminance by projecting a plurality of projectors so as to superimpose the same image on the same location.

  When performing multi-projection or stack projection, it is complicated to strictly adjust the superimposed region, and thus automation of the operation is required. As a method of automating the correction, a method is known in which a projection image of a projector is captured by a camera, and the captured image is analyzed to automatically change the position and shape of the projection of the projector. At this time, it is necessary to appropriately determine the exposure of the camera in order to appropriately capture the image projected by the projector.

  Patent Literature 1 proposes a method of appropriately determining an exposure value of a camera by capturing a projection image.

JP 2006-47338 A

  However, in a system using a plurality of projectors and one camera, it may be troublesome for the user to previously install the camera at an appropriate position in order to appropriately determine the exposure value of the camera.

  An object of the present invention is to reduce the trouble of a user who previously installs a camera at an appropriate position in determining an exposure value of a camera suitable for a projected image.

To achieve the above object, a projection system according to the present invention comprises:
Multiple projectors,
A camera capable of imaging a projection plane projected by the plurality of projectors,
One or more control units for controlling the plurality of projectors and the camera,
A projection system comprising:
The control unit obtains the brightness of a predetermined area by the camera in a state where a pattern is projected on only one of the plurality of projectors by the number of the plurality of projectors. The exposure value of the camera is determined on the basis of the value between the maximum and minimum values of.

  ADVANTAGE OF THE INVENTION According to the projection system which concerns on this invention, the trouble of the user who installs a camera can be reduced.

Example of system configuration Stack projection Example of system configuration In case of multiple projection An example of a functional block diagram of the system Example of system processing flow Example of a flowchart of camera setting processing Diagram showing imageable area of camera An example of a flowchart of the automatic positioning process Diagram showing the brightness of the projector

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings, but the present invention is not limited to the following embodiments. Further, the embodiments of the present invention show preferred embodiments of the present invention, and do not limit the scope of the invention.

<First embodiment>
[System Configuration of the Present Embodiment]
The configuration of the system according to the present embodiment will be described with reference to FIGS. FIG. 1 is a diagram illustrating an example of a configuration of a system using two projectors.

  FIG. 1 shows an embodiment in which two projectors are superimposed and projected on the same projection plane in order to improve brightness and display a 3D image of a projection image. Hereinafter, such a projection form is referred to as a stack projection. The projector 100a and the projector 100b project an image, and project one image on a projection surface by superimposing the images. The projector 100a, the projector 100b, and the PC 200 are connected via a LAN cable so as to be able to communicate with each other. The connection format may be wired or wireless as long as communication is possible. Further, another method such as serial communication may be used.

  The PC 200 supplies a video signal to the video distributor 300 using a video cable. The video distributor 300 supplies video signals to the projectors 100a and 100b via a plurality of video cables. The format of the video signal may be any format such as HDMI (registered trademark), DVI, and VGA.

  The video distributor 300 duplicates the video signal received from the PC 200 and supplies it to the projector 100a and the projector 100b.

  The camera 400 is connected to the PC 200 via a USB cable, shoots a projection plane based on a shooting instruction from the PC 200, and transmits a shot image to the PC 200. The connection may be established by a LAN. The camera 400 only needs to be able to capture an image based on an instruction from the PC 200, and the type of camera is not limited.

  FIG. 2 shows a mode in which four projectors are overlapped on a projection plane to partially enlarge a projection image in order to enlarge the screen and increase the resolution of the projection plane. Hereinafter, such a projection form is referred to as multi-projection. By performing light reduction processing (edge blending) on the superimposed portion on the projection surface, the superimposed portion can be made inconspicuous. In this configuration, four projectors are connected to one PC via the video distributor 300. The connection format of the video cable, the LAN cable, and the USB cable is the same format as the case of the stack projection shown in FIG. In the case of multi-projection, the image distributor 300 divides and distributes a region to be projected for each projector.

  In the present embodiment, for simplicity of explanation, a case of stack projection using two projectors as shown in FIG. 1 and a case of multi-projection using four projectors as shown in FIG. Although described, the number and arrangement are not limited to this.

[Configuration of Projector 100]
FIG. 3 is a diagram showing a main configuration of the projector 100, the PC 200, the video distributor 300, and the camera 400 that constitute the system. The configuration of the system will be described with reference to FIG.

  The projector 100 according to the present embodiment includes a CPU 101, a RAM 102, a ROM 103, a projection unit 104, a projection control unit 105, a VRAM 106, an operation unit 107, a network IF 108, an image processing unit 109, and a video input unit 110. An internal bus 111 connects the above blocks. The CPU 101 controls each operation block of the projector 100. The RAM 102 temporarily stores a control program and data as a work memory. The ROM 103 is for storing a control program describing a processing procedure of the CPU 101.

  The projection unit 104 is for projecting an image specified by a projection control unit 105 described later, and includes a liquid crystal panel (not shown), a lens, and a light source. The projection control unit 105 reads out image data stored in the VRAM 106 and issues a projection instruction to the projection unit 104. The VRAM 106 is an area for storing an image projected by the projection unit 104.

  The operation unit 107 receives an instruction from a user and transmits an instruction signal to the CPU 101. For example, it consists of a switch and a dial. The operation unit 107 may receive a signal from a remote controller (not shown) and send an instruction signal corresponding to the received signal to the CPU 101. The network IF 108 is for performing network communication with an external device. In the present embodiment, the network IF 108 is used for communication with the PC 200.

  The image processing unit 109 performs a process of changing the number of frames, the number of pixels, an image shape, and the like on a video signal received from a video input unit 110 described below, and transmits the processed signal to the projection control unit 105. Consists of a microprocessor. The image processing unit 109 does not need to be a dedicated microprocessor. For example, the CPU 101 may execute the same processing as the image processing unit 109 by using a program stored in the ROM 103. The image processing unit 109 can execute functions such as frame thinning processing, frame interpolation processing, resolution conversion processing, OSD superimposition processing such as menus, distortion correction processing (keystone correction processing), and edge blending. These functions can be instructed to be executed by the CPU 101 even when a command is received from an external device via the network IF 108.

  The video input unit 110 receives a video signal from an external device, and includes, for example, a composite terminal, an S video terminal, a D terminal, a component terminal, an analog RGB terminal, a DVI-I terminal, a DVI-D terminal, and an HDMI (registered). Trademark) terminals and the like. When an analog video signal is received, the received analog video signal is converted into a digital video signal. Then, the received video signal is transmitted to the image processing unit 109. Here, the external device may be any device such as a personal computer, a camera, a mobile phone, a smartphone, a hard disk recorder, a game machine, etc., as long as it can output a video signal.

[Configuration of PC 200]
Next, the PC 200 will be described.

  The PC 200 according to the present embodiment includes a CPU 201, a RAM 202, a ROM 203, an operation unit 204, a display unit 205, a network IF 206, a video output unit 207, and a communication unit 208. An internal bus 209 connects the above blocks.

  The CPU 201 controls each operation block of the PC 200. The RAM 202 temporarily stores a control program and data as a work memory. The ROM 203 is for storing a control program describing a processing procedure of the CPU 201.

  The operation unit 204 receives an instruction from a user and transmits an instruction signal to the CPU 201. For example, it includes a mouse, a keyboard, a touch panel, and the like. The display unit 205 displays image data and a UI screen. The display unit 205 is, for example, a liquid crystal panel or an organic EL panel.

  The network IF 206 is for performing network communication with an external device for the purpose of controlling the external device. In the present embodiment, communication is performed with the projector 100 connected to the LAN. In the present embodiment, the projector 100 is controlled by LAN communication. However, the present invention is not limited to LAN communication, and other communication methods may be used. For example, serial communication (RS-232) may be used. In that case, it connects to the projector 100 via the communication unit 208 described later.

  The video output unit 207 transmits a video signal to an external device. For example, a composite terminal, an S video terminal, a D terminal, a component terminal, an analog RGB terminal, a DVI-I terminal, a DVI-D terminal, an HDMI ( (Registered trademark) terminals. Here, the external device is not limited to a projector as long as it can input a video signal, and may be any device such as a display device or a video distributor. In the present embodiment, the external device is a projector, and is connected via the video distributor 300. Further, in the present embodiment, a description will be given assuming that a UI screen for allowing a user to perform a user operation is displayed on the display unit 205, but the UI screen is displayed on an external device connected to the video output unit 207. There may be.

  The communication unit 208 transmits and receives a signal including a shooting instruction and an exposure correction instruction and a shot image to and from the camera 400. For example, the communication unit 208 performs transmission and reception according to a standard such as USB (Universal Serial Bus). In the present embodiment, the PC 200 and the camera 400 are described as being connected by USB via the communication unit 208. However, if the camera can be controlled by a network, the camera may be connected to the network via the network IF 206.

[About distributor 300]
In the system described in this case, the distributor 300 plays a role of transmitting necessary image data from the PC 200 to the plurality of projectors 100. If image data can be transmitted from PC 200 to projector 100 by another means (for example, network communication), distributor 300 is unnecessary. Also, when the video output unit 207 of the PC 200 and the video input units 110 of the plurality of projectors 100 can be directly connected by a video cable, the distributor 300 is unnecessary.

[About Camera 400]
The camera 400 according to the present embodiment includes a CPU 401, a RAM 402, a ROM 403, an optical unit 404, an optical control unit 405, an image sensor 406, an image processing unit 407, a VRAM 408, and a communication unit 409. An internal bus 410 connects the above blocks. The CPU 401 controls each operation block of the camera 400. The RAM 402 temporarily stores a control program and data as a work memory. The ROM 403 is for storing a control program describing a processing procedure of the CPU 401.

  The optical unit 404 includes a lens and a shutter (not shown). The optical control unit 405 controls the lens and shutter of the optical unit 404 to change exposure, focus, and zoom. The image sensor 406 receives light passing through the optical unit 404 from outside the camera 400 and converts the light into an electric signal. In addition, amplification of an electric signal can be performed. The setting of the value of the ISO sensitivity as an index of amplification is performed by the CPU 401. The image processing unit 407 can process image information such as A / D conversion of an electric signal obtained from the image sensor 406. The VRAM 408 is an area for storing an image. The communication unit 409 is an area for performing communication with the outside. Information for control and image information are communicated.

In the present embodiment, the projector 100, the PC 200, the distributor 300, and the camera 400 are described as separate devices, but the devices may be combined to form an integrated device.
For example, one of the projectors 100 and the PC 200 can be an integrated device. In that case, the CPU 101 of the projector 100 and the CPU 201 of the PC 200 may be one common CPU. Thus, the combination of the devices and the common use of the components can be appropriately implemented.

[Overview of system processing flow]
FIG. 4 shows a processing flow of the system described in the present embodiment. This processing flow is performed by the CPU 201 of the PC 200. First, an overview of the entire flow will be described. A detailed description of each flow will be described later.

  In S100, a plurality of projectors 100 connected to the PC 200 via the network are searched, and a target projector is selected.

  In S200, each of the projectors 100 selected in S100 projects an installation confirmation test pattern on the projection plane, and prompts the user to confirm the physical arrangement of the projector 100.

  In S300, a mode is selected in which the automatic alignment process performed in S600 is a stack projection or a multi projection.

  In S400, one camera 400 to be used for correction is selected from one or more cameras 400 connected to the PC 200 because a plurality of cameras may be connected, though not shown.

  In S500, settings are made to make the setting parameters (exposure value, white balance, etc.) of the camera 400 selected in S400 suitable for the subsequent automatic alignment processing (S600).

  Finally, in S600, the CPU 201 instructs the CPU 401 of the camera 400 to photograph the automatic alignment test pattern projected by the projector 100 on the projection plane via the communication unit 208, and based on the photographed image, The amount of deformation required for 100 position alignment is calculated. For example, a keystone correction amount is calculated. The CPU 201 transmits a deformation command to each of the projectors 100 selected in S100 to the projectors 100 via the network IF 206, thereby performing alignment.

  The order of the flow does not have to be as shown in FIG. For example, the camera selection process (S400) may be performed first, and the automatic alignment mode setting (S300) may be performed later.

  The above processing is performed by the CPU 201 of the PC 200. However, it is also possible to determine whether to proceed with the processing, select a mode in S300, and the like based on a user instruction to the operation unit 204 of the PC 200. That is, the CPU 201 executes the content specified by the user on the operation unit 204. Also, the CPU 201 of the PC 200 can generate a GUI and display it on the display unit 205 of the PC 200 to prompt the user for an instruction.

  This is the end of the overview of the processing flow of the present embodiment. Next, each flow will be described in detail.

[Target projector selection processing]
The target projector selection processing (S100) shown in FIG. 4 will be described.

  CPU 201 of PC 200 transmits a predetermined broadcast packet including a request for an IP address via network IF 206. When receiving the broadcast packet via network IF 108, CPU 101 of projector 100 transmits a packet including its own IP address to PC 200. When the CPU 201 of the PC 200 receives the packet sent from the projector 100, the CPU 201 extracts information including the IP address from the packet and stores the information in the RAM 202. Some of the projectors 100 may be selected from all the projectors 100. The user selects the projector 100 with the operation unit 204, and the CPU 201 can execute the content.

  This concludes the description of the target projector selection processing in S100.

[Test pattern output processing for installation position confirmation]
The test pattern output processing for installation position confirmation (S200) shown in FIG. 4 will be described.

  The CPU 201 of the PC 200 transmits a command for performing a test pattern to the projector 100 selected in S100 via the network IF 206, and projects and displays the test pattern on each of them. As the test pattern, for example, a test pattern previously stored in the VRAM 106 is used. The test pattern projected on the projector 100 is, for example, a lattice pattern. The user can see the projection plane shown in FIGS. 1 and 2 and check the projected position. The user can roughly adjust the position of the projection plane by moving the projector 100 or the like.

  Note that the test pattern need not be stored in the VRAM 106 of the projector 100. For example, an image output from the video output unit 207 of the PC 200 and input to the video input unit 110 of the projector 100 may be used as the test pattern. Good.

  This concludes the description of the test pattern output processing for installation position confirmation in S200.

[Automatic alignment mode selection process]
The selection process (S300) of the automatic positioning mode shown in FIG. 4 will be described.

  The user can use the operation unit 204 of the PC 200 to select whether to perform the automatic alignment of the stack projection as shown in FIG. 1 or to perform the automatic alignment of the multi-projection as shown in FIG. it can. The CPU 201 of the PC 200 stores the mode in the RAM 202 for the selected automatic alignment.

  This concludes the description of the automatic alignment mode selection process in S300.

[Selection of camera to use]
The camera selection process (S400) shown in FIG. 4 will be described.

  The CPU 201 of the PC 200 acquires a list of connected cameras via the communication unit 208 and stores the list in the RAM 202. When the CPU 201 of the PC 200 detects that the user has selected one camera 400 by the operation unit 204 of the PC 200, the information of the selected camera is stored in the RAM 202. The CPU 201 of the PC 200 establishes communication for control with the selected camera, thereby enabling operations such as photographing and changing an exposure value.

  This concludes the description of the camera selection process used in S400.

[Camera setting process]
The camera setting process (S500) shown in FIG. 4 will be described with reference to the flowchart shown in FIG. 5 and FIG.

  First, a preferable state of the system at the start of the camera setting process will be described. FIG. 6A shows a captured image obtained by shooting the multi-projection as shown in FIG. In FIG. 6A, the projection plane 600a corresponds to the projection plane of the projector 100a. Similarly, the projection plane 600b corresponds to the projector 100b, the projection plane 600c corresponds to the projector 100c, and the projection plane 600d corresponds to the projector 100d. As the projected pattern, for example, the installation confirmation test pattern described in S200 can be used together.

  At the start of the camera setting process shown in FIG. 5, it is preferable that the projection planes of all the projectors 100 fall inside the imageable area 601 of the camera 400 as shown in FIG. This is because, in the automatic positioning process in S600, it is preferable that the camera 400 can capture the entire projection surface of all the projectors 100, and it is not preferable to move the camera after performing the camera setting process in S500. is there.

  If the projection planes of all the projectors 100 are not within the imageable area 601 of the camera 400, the user physically moves the camera 400 or changes the zoom of the camera 400. Such camera adjustments can be troublesome for the user. If the captured image of the camera 400 is displayed on the display unit 205 of the PC 200 in a live view, the user can adjust the camera 400 while looking at the display unit 205, so that the user's labor can be reduced. For this purpose, the CPU 201 constantly obtains an image captured by the camera 400 through the communication unit 208 and causes the display unit 205 to display the captured image.

  Next, the flowchart of FIG. 5 will be described. This processing flow is performed by the CPU 201 of the PC 200.

  S501 is a determination process for making a determination for projecting the brightness measurement pattern on the target projector in order.

  In step S502, the CPU 201 of the PC 200 instructs the CPU 101 of the target projector 100 to project the brightness measurement pattern via the video output unit 207 or the network IF 206 based on the target projector information stored in the RAM 202. I do. At this time, only one projector projects the brightness measurement pattern, and the display is turned off for the other projectors. As a method for turning off the display, the CPU 201 of the PC 200 transmits a black image, or transmits a BLANK command to the projector 100 if the projector 100 has a BLANK function. The brightness measurement pattern is, for example, an image in which the entire projectable area is whitened, but may be different in color or pattern as long as the pattern can measure brightness.

  In step S <b> 503, the CPU 201 of the PC 200 sends a command for instructing brightness measurement to the CPU 401 of the camera 400 selected in step S <b> 400 via the communication unit 208 to cause brightness measurement. For the brightness measurement, the photometry function of the camera 400 can be used. In the photometry function, the CPU 401 of the camera reads out a program stored in the ROM 403 and performs the program inside the camera 400. The photometry function is a function of calculating the brightness of a captured image and calculating a value related to the brightness based on the calculated brightness. The value related to the brightness is a value related to the brightness of the captured image when the camera 400 captures an image, such as the F value, the shutter speed value, and the ISO sensitivity value of the camera 400 calculated by the photometry function. The photometric function includes a method using the entire image captureable area of the camera 400 (average photometry) and a method using a part thereof. In the present embodiment, as shown in FIG. 6B, information only inside a predetermined area 603 which is a part of the imageable area 602 is used. The photometric function may be realized by measuring the brightness using a photometric sensor for the photometric function in the camera.

  The reason why it is preferable to use the predetermined area 603 will be described below. FIG. 6C shows that, in addition to FIG. 6A, outside light 604 that is not a projection is inside the imageable area 601. The external light 604 is generated by, for example, sunlight or room lighting. If the external light 604 is brighter than the brightness of the projection, in the photometric function using all of the imageable area 601, the brightness calculated due to the influence of the external light 604 increases, and the brightness of the projection is calculated. May not be suitable for On the other hand, the use of the predetermined area 603 as shown in FIG. 6B makes it less likely to be affected by the external light 604, resulting in a photometry suitable for calculating the brightness of the projection.

  The CPU 401 of the camera 400 sends the brightness or the value related to the brightness calculated by the photometry function to the CPU 201 of the PC 200 via the communication unit 409, and the CPU 201 of the PC 200 writes the received information to the RAM 202. This value is sent by the number of projectors 100.

  In step S504, the CPU 201 of the PC 200 reads the brightness from the RAM 202, compares the brightnesses, and selects the maximum brightness. The reason for selecting the maximum brightness is that, for example, even if there is a projector that does not overlap the predetermined area 605 as shown in FIG. 6D, the brightness corresponding to the projector that overlaps the predetermined area 605 can be used. It is. Specifically, when the brightness is acquired only in the predetermined area 603, the brightness of the projection plane 600b or 600d cannot be acquired, but the brightness of the projection plane 600a or 600c can be acquired. That is, when the user installs the camera 400, if the projection plane of any one of the projectors is superimposed on the predetermined area 605 of the camera 400, the brightness of the projection plane of at least one projector can be acquired. If the brightnesses of the projectors are approximately the same, it can be said that approximately the desired brightness can be obtained by obtaining the brightness of the projection surface of at least one projector. Therefore, for example, as compared with the case where the camera 400 is installed so that the projection planes of all the projectors are superimposed on the predetermined area 605 of the camera 400, the time and effort for the user to install the camera can be reduced.

  The CPU 201 of the PC 200 refers to the table stored in the ROM 203 in advance, and determines the exposure of the camera 400 suitable for capturing the test pattern for automatic alignment in the automatic alignment processing of S600 based on the received brightness and the value regarding the brightness. Calculate the value. Specifically, an F value, a shutter speed value, an ISO sensitivity value, and the like of the camera 400 are calculated.

  In step S505, the CPU 201 of the PC 200 sends the calculated exposure value to the CPU 401 of the camera 400 via the communication unit 208, and stores the calculated exposure value in the RAM 402 of the camera 400. Further, the CPU 201 of the PC 200 causes the CPU 401 to set parameters relating to the exposure value of the camera 400.

  Although the photometric function of the camera 400 is used in S503 as described above, there is a method that does not use the photometric function of the camera 400. Specifically, there is a method in which a plurality of images captured by the camera 400 are sent to the PC 200, and the CPU 201 performs image processing inside the PC 200, and compares the brightness of a predetermined area of each image. However, in this method, since an image is sent between the communication unit 208 and the communication unit 409, the transfer time is longer than when the photometric function of the camera 400 is used. By using the photometric function of the camera 400, the time required for the camera setting process in S500 can be reduced.

  In the description of the camera setting process in S500, multi-projection is taken as an example, but the same applies to stack projection. Further, the number of projectors may be different.

  This is the end of the description of the camera setting process in S500.

[Automatic alignment processing]
The automatic positioning process (S600) shown in FIG. 4 will be described with reference to the flowchart shown in FIG.

  S701 is a determination process for performing a determination for sequentially projecting the automatic alignment test pattern on the target projector for automatic alignment.

  In S702, the CPU 201 of the PC 200 causes the target projector 100 to project a test pattern for automatic alignment via the video output unit 207 or the network IF 206 based on the target projector information stored in the RAM 202. At this time, only one projector projects the test pattern for automatic positioning, and the CPU 201 of the PC 200 transmits a black image or a BLANK command to the other projectors, thereby turning off the display. To

  In step S <b> 703, the CPU 201 of the PC 200 transmits an imaging command and a download command of the captured image to the camera 400 via the communication unit 209. Upon receiving the photographing command and the photographed image download command, the CPU 401 of the camera 400 photographs the projection plane and transmits the photographed image to the PC 200 via the communication unit 409. The CPU 201 of the PC 200 stores the captured image in the RAM 202 for later calculation processing.

  In step S704, the CPU 201 of the PC 200 calculates a deformation parameter (for example, a keystone correction amount) of each projector based on the captured image stored in the RAM 202 and the set value of the automatic alignment mode. Note that an algorithm for calculating the deformation parameter may use a known method, and a description thereof will be omitted.

  In S705, the CPU 201 of the PC 200 transmits a deformation command including a deformation parameter to each projector 100 via the network IF 206. Upon receiving the transformation command, the CPU 101 of each projector 100 instructs the image processing unit 109 to transform the input image.

  This concludes the description of the automatic positioning process in S600.

<Embodiment 2>
The second embodiment of the present invention is characterized in that the CPU 201 compares the brightnesses of the projectors 100 and determines the exposure value of the camera 400 based on a value between the maximum value and the minimum value of the brightness. A description of the same points as in the first embodiment will be omitted.

  In the first embodiment, the maximum value of the brightness is selected in S504. However, in the second embodiment, not only the maximum value but also a value between the maximum value and the minimum value of the brightness (including the maximum value) can be selected. Show. FIG. 8A shows brightness 801, brightness 802, and brightness 803 which are the results of brightness measurement of each of the three projectors 100. In the second embodiment, three projectors are used for the sake of simplicity. The brightness 801 is dark because the projection surface of the projector 100 does not overlap the predetermined area 603, and the brightness 802 and the brightness 803 are such that the projection surface of the projector 100 overlaps the predetermined area 603. It is bright because it is. The cause of the difference between the brightness 802 and the brightness 803 depends on the individual difference of the light source of the projector 100, the installation position of the projector 100, and the like.

  In S504, it is assumed that the CPU 201 compares the brightnesses and selects the median value of the brightness. In the case of FIG. 8A, the brightness 802 is selected. With reference to the table, the CPU 201 calculates the exposure value of the camera 400 suitable for capturing the automatic alignment test pattern in the automatic alignment processing of S600 based on the brightness 802. Even when the exposure value calculated with reference to the brightness 802 is slightly brighter or darker than the brightness 802, it is possible to preferably capture an automatic alignment test pattern in the automatic alignment process of S600. This range of brightness is shown between two broken lines in FIG. Therefore, in the case of FIG. 8A, since the brightness 803 falls within this range, it is possible to preferably capture an image of the test pattern for automatic alignment of the projector 100 corresponding to the brightness 803.

  On the other hand, the brightness 801 is dark because the projection surface of the projector 100 is not superimposed on the predetermined area 603, but is superimposed on the predetermined area 603 by slightly changing the direction of the camera 400, It is measured as bright as the brightness 811 in FIG. 8B is the same projector 100 as the brightness 802, and the brightness 813 is the same projector 100 as the brightness 803. Under the conditions of FIG. 8B, similarly to FIG. 8A, if the CPU 201 compares the brightnesses in S504 and selects the median brightness, the brightness 812 is selected. If the brightness 812 is an exposure value calculated with reference to the table, the projector 100 having the brightness 811 and the brightness 813 can appropriately capture an automatic alignment pattern.

  From the above description, even if one of the three projectors does not have a projection plane superimposed on the predetermined area 603, an exposure value suitable for capturing an automatic alignment pattern of the three projectors is determined. It can be said that. The user does not need to superimpose the projection planes of all the projectors 100 on the predetermined area 603, rather than superimposing the projection planes of all the projectors 100 on the predetermined area 603, which reduces the user's trouble of installing the camera 100. Can be done.

  Although the median value is used in the present embodiment, any value between the maximum value and the minimum value of the brightness (including the maximum value) can be used as long as the median value is used. Further, another value other than the median value can be selected.

  As described above, by determining the exposure value of the camera 400 based on the value between the maximum value and the minimum value of the brightness, the user does not need to superimpose the projection planes of all the projectors 100 on the predetermined area 603. Therefore, it is possible to reduce the trouble of the user who installs the camera 400.

<Embodiment 3>
According to the third embodiment of the present invention, the CPU 201 calculates a brightness difference between a state where the projector 100 is projecting the brightness measurement pattern and a state where the projector 100 is not projecting the brightness measurement pattern, and determines whether the difference exceeds a certain threshold value. Is determined. A description of the same points as in the first embodiment will be omitted.

  In the first embodiment, in the camera setting process in S500, the CPU 201 measures the brightness of all the projectors 100. However, in the second embodiment, in addition to this, the brightness measurement in a state where none of the projectors 100 is projecting is performed. I do. If the difference in brightness between the projected state and the non-projected state is equal to or smaller than a certain threshold value, it can be determined that the projection plane does not overlap the predetermined area 603 in FIG. When it is determined that the projection planes of all the projectors 100 do not overlap the predetermined area 603, the CPU 201 can notify the user that the camera 400 is not properly installed, for example, through the display unit 205. This allows the user to know that the installation of the camera 400 is not appropriate and determine that the installation of the camera 400 should be performed appropriately.

<Embodiment 4>
Embodiment 4 of the present invention is characterized in that the predetermined area 603 is shown to the user. A description of the same points as in the first embodiment will be omitted.

  FIG. 6E shows a live view captured by the camera 400. The CPU 201 of the PC 200 acquires the live view of the camera 400, and displays the acquired live view on the display unit 205. The imageable area 607 is the entire area in which an image can be captured. The photometric position display section 606 displays a position used for photometry. The position of the predetermined area 603 and the position of the photometry position display unit 606 in FIG. 6B are the same as the position of the imageable area 602 or the imageable area 607. As in the present embodiment, the shape of the predetermined area 603 and the shape of the photometric position display unit 606 may be different or the same. The shape is not limited to a circle or a cross, but may be any shape. Further, the CPU 201 may cause the display unit 205 to display a message prompting the user to superimpose the photometric position display unit 606 and the imaged projection surface of the projector 100.

  The user can check the photometry position display unit 606 of the display unit 205 of the PC 200 to check whether the light is superimposed on the projection plane of the projector 100. Therefore, as compared with the case where the photometric position display unit 606 is not displayed, the trouble of the user who installs the camera 400 can be reduced.

<Embodiment 5>
Embodiment 5 of the present invention is characterized in that the position of the predetermined area 603 can be changed by the user. A description of the same points as in the first embodiment will be omitted.

  In FIG. 6B, the predetermined area 603 is located near the center of the imageable area 602, but the present invention is not limited to this. The predetermined area 603 may be anywhere within the imageable area 602. The CPU 201 of the PC 200 can indicate the predetermined area 603 on the display unit 205. The user can instruct the position of the predetermined area 603 by operating the operation unit 204 while looking at the display unit 205. The CPU 201 sends a command to the camera 400 via the communication unit 208 so that the position is instructed by the user, and the CPU 400 of the camera 400 can change the position of the predetermined area 603 according to the received command.

  As described above, since the user can change the predetermined area 603, the user can perform an operation to superimpose the predetermined area 603 on the projection surface of the projector 100 without changing the installation of the camera. Therefore, it is possible to reduce the labor for the user to install the camera.

<Other embodiments>
It is needless to say that the object of the present invention can be attained also by supplying a storage medium storing a program code of software for realizing the functions of the above-described embodiments to the apparatus. At this time, the computer (or CPU or MPU) including the control unit of the supplied apparatus reads out and executes the program code stored in the storage medium.

  In this case, the program code itself read from the storage medium realizes the function of the above-described embodiment, and the program code itself and the storage medium storing the program code constitute the present invention.

  As a storage medium for supplying the program code, for example, a flexible disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a CD-R, a magnetic tape, a nonvolatile memory card, a ROM, and the like can be used.

  An OS (basic system or operating system) or the like running on the apparatus performs part or all of the processing based on the instructions of the program code, and the processing realizes the functions of the above-described embodiments. Needless to say, cases are included.

  Furthermore, the program code read from the storage medium may be written in a memory provided in a function expansion board inserted into the apparatus or a function expansion unit connected to a computer, and the functions of the above-described embodiments may be realized. Needless to say, it is included. At this time, a CPU or the like provided in the function expansion board or the function expansion unit performs part or all of the actual processing based on the instruction of the program code.

  As described above, the embodiment can be implemented in other various forms, and can be omitted, replaced, or changed without departing from the spirit of the invention.

100 projector, 200 PC, 300 distributor, 400 camera

Claims (6)

Multiple projectors,
A camera capable of imaging a projection plane projected by the plurality of projectors,
One or more control units for controlling the plurality of projectors and the camera,
A projection system comprising:
The control unit obtains the brightness of a predetermined area by the camera in a state where a pattern is projected on only one of the plurality of projectors by the number of the plurality of projectors. A camera exposure value is determined based on a value between a maximum value and a minimum value of the camera. The control unit obtains the brightness of a predetermined area by the camera in a state where a pattern is projected on only one of the plurality of projectors by the number of the plurality of projectors. Calculating a difference between the brightness obtained in the predetermined area by the camera and not projecting all of the plurality of projectors, and determining whether the calculated difference exceeds a certain threshold. The projection system according to claim 1. The projection system according to claim 1, wherein the control unit displays a position of the predetermined area to a user. 2. The projection system according to claim 1, wherein the control unit can change a position of the predetermined area based on a user's instruction. 3. The projection system according to claim 1, wherein the step is performed by using a photometry function of the camera. Obtaining a brightness of a predetermined area by a camera in a state where a pattern is projected on only one of the plurality of projectors by the number of the plurality of projectors;
Determining an exposure value of the camera based on a value between a maximum and a minimum of the obtained plurality of brightnesses;
A control method for a projection system, comprising: