JP2020086189A - Projection system - Google Patents

Abstract

To provide a system that improves a deviation of an application timing of a parameter in a plurality of projection devices.SOLUTION: A projection system comprises a plurality of projectors 100 that project images using a plurality of division frames generated from each of a plurality of frames. The projector 100 comprises: an image processing unit 109 that acquires an amount of statistics of the frame; a network IF108 that acquires an amount of statistics of the frame and information indicative of a frame number from other projection device; and a projection control unit 105 that projects the image on the basis of an object frame. The projection control unit 105 is configured to, when acquiring the amount of statistics of the frame preceding by predetermined pieces of frames from the object frame from other projector 100, determine a projection parameter from the amount of statistics corresponding to the frame preceding by predetermined pieces of frames, otherwise, determine the projection parameter used in projecting the image of the frame prior to the object frame as the projection parameter with respect to the object frame.SELECTED DRAWING: Figure 6

Description

The present invention adjusts the display control timing in multi-display.

As a method of using a projector, a projection method (multi-projection) is known in which images are formed by connecting projection images from a plurality of projectors. When a plurality of display devices are combined to display one image in this way, the frame of the image to be displayed is shifted for each projection device due to the difference in the image control or the display timing difference in each display device. There is a problem that the bankruptcy will occur.

With respect to such a problem, Patent Document 1 discloses a technique capable of performing video display in synchronization with a plurality of display devices. Specifically, the delay can be measured from the time difference between the input of the image signal and the actual output of the projection light, and the delay can be considered to synchronize the plurality of display devices.

JP, 2017-16027, A

At the time of multi-projection, it is assumed that dynamic contrast processing, which is processing for controlling the light source and the gradation of the frame, is performed based on the average luminance (statistical amount) of one frame of the input image. In such a case, each projector must control the light source and gradation using the same control value. Therefore, it is necessary to share the statistic required for calculating the control value between the projectors and apply it to the video at the same timing.

When Patent Document 1 is applied in such a case, no technology relating to sharing and application of parameters such as statistics is disclosed, and therefore, depending on a sharing method of sharing statistics between projectors, they are applied to video at the same timing. Sometimes you can't. For example, when parameters are shared via a network, if the network is delayed, the parameters cannot be applied to the video at the same timing.

Therefore, the present invention provides a projection system that improves the deviation of the application timing of the shared parameter even in the processing in which the parameters need to be shared by the respective projection devices when displaying an image using a plurality of projection devices. The purpose is to do.

In order to achieve the above object, the projection system according to the present invention comprises:
A projection system comprising a plurality of projection devices, wherein each projection device comprises a video input means, a predetermined frame number determination means for determining a predetermined number of frames, and a statistical amount from the video input by the video input means. And a frame number acquisition unit that acquires a frame number of a frame for which the statistic is acquired, an associating unit that associates the frame number with the statistic, and the associated frame number and the Recording means for recording a statistic, communication means for communicating the frame number and the statistic associated with another display device, a latest frame acquisition means for acquiring a latest frame, and the latest frame A used frame number acquisition unit that acquires a frame number before a predetermined number of frames, the frame number received from another display device by the communication unit, and the frame number recorded in the own display device by the recording unit are used frames. Matching determining means for determining whether they match the frame number, and reception determining means for checking whether or not the statistics associated with the frame numbers determined to match by the matching determining means are available for the number of connected devices. A matching unit for calculating one statistic based on the statistic for the number of connected devices determined to be complete by the reception determining unit; and a video display unit for displaying a video. If it is determined by the means, and it is determined by the reception determination means that they are aligned, the light source control and image processing are performed based on the statistic calculated by the calculation means, and the match determination means If it is determined that they do not match, or if the reception determination means determines that they do not match, light source control and image processing are performed based on the previously used statistics.

According to the present invention, when displaying an image using a plurality of projection devices, even in a process in which each projection device needs to share a parameter, each projection device can share a statistical amount accompanied by time information. Thus, it is possible to provide a projection system that improves the deviation of the application timing of the shared parameters.

It is a figure which shows an example of a projection system structure. It is a block diagram which shows the functional block of a projector and a projection control apparatus. 7 is a flowchart showing a display control process during multi-projection in the first embodiment. It is a figure explaining the subject which occurs when this invention is not applied. It is a figure showing the brightness difference which occurs when the present invention is not applied. It is a figure explaining that a subject is solved when the present invention is applied. 9 is a flowchart showing a display control process at the time of multi-projection in the second embodiment. 9 is a flowchart showing a first delay value updating process in the second embodiment. FIG. 9 is a diagram showing an example of reception determination in the second embodiment. FIG. 9 is a diagram showing a second delay value at the time of updating the first delay value in the second embodiment.

Hereinafter, examples 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 invention, and do not limit the scope of the invention.

<Practical example 1>
FIG. 1 is a diagram showing an example of the configuration of a projection system of this embodiment.

The projection system includes projectors 100a, 100b, and 100c, a projection control device 200, and a video distributor 300. The projection system is a multi-projection system that combines the projection images projected from the projectors 100a, 100b, and 100c to project one image. The projectors 100a, 100b, 100c may be displays.

The projector 100a is a projection device that projects the projection image A on the projection surface 400. The projector 100b is a projection device that projects the projection image B on the projection surface 400. The projector 100c is a projection device that projects the projection image C on the projection surface 400. Hereinafter, when referring to each of the projectors individually, reference numerals of the projector 100a, the projector 100b, and the projector 100c are respectively attached. When referring to the configuration and processing common to the projectors, the projector 100 is used.

It is assumed that each of the projectors 100a to 100c is installed in advance so as to display one image on the projected images A to C.

At this time, if the video signals input to the respective projectors are not synchronized, different images will be projected on the respective projectors. In this embodiment, the video signal output by the video distributor 300 is frame-synchronized.

The projection control device 200 is a control computer that is connected to the projector 100 via a network and controls the projector 100. In this embodiment, it is assumed that the communication between the projector 100 and the projection control apparatus 200 is performed on a local area network (LAN) that uses TCP/IP as a communication protocol.

The control computer may be an information processing device such as a PC, a smartphone, or a tablet. Communication between the projector 100 and the projection control apparatus 200 may be wired communication or wireless communication, and the communication protocol is not particularly limited. Moreover, the projection control device 200 can control the operation of the projector 100 by transmitting a predetermined command to the projector 100. The projector 100 performs an operation according to the command received from the projection control apparatus 200, and transmits the operation result to the projection control apparatus 200.

The video distributor 300 duplicates the video signal received from the projection control apparatus 200 and supplies it to each of the projectors 100a to 100c.

Here, the projection control apparatus 200 is assumed to store a video signal in which a plurality of frames (original frames) are arranged in order in a storage medium. Further, the projection control device 200 generates a plurality of divided frames that are divided according to the number of the plurality of projectors connected to each frame and the projection positions of the plurality of projectors. The projection control device 200 sequentially outputs the corresponding divided frames to each projector via the video distributor 300. As described above, the divided frames output from the video distributor 300 to each projector are synchronized. That is, it is assumed that a plurality of divided frames generated from the same frame are simultaneously output to each projector.

Each projector projects an image on a projection surface based on a video signal composed of a plurality of divided frames that are sequentially input. Here, each projector projects an image according to the characteristics of the frame by performing brightness of the light source and image processing according to the brightness level of the input frame. Specifically, when the maximum value or average value of the brightness levels of the input frame is smaller than a predetermined threshold value, the light emission amount of the light source is reduced more than in the other cases. This makes it possible to suppress so-called black floating when a dark image with a low brightness level is projected. However, when such a projector is used in the multi-projection system as described above, if the light source control or the like is independently performed on the divided frames input by each projector, the light emission amounts of the light sources do not match between the projectors. There is a concern that image effects such as black level differences between projected images may occur.

The projector 100 according to the present exemplary embodiment acquires and acquires the statistic amount of the input divided frame (first divided frame), and also obtains the divided frame (second divided frame) input from another projector to the other projector. The statistic and the information indicating the frame number of the second divided frame that is the basis of the statistic are acquired. Furthermore, the projector 100 is configured to display the statistic amount acquired from a predetermined number of divided frames before the divided frame (target frame) used for projecting an image, and to the other projectors generated from the same original frame as the divided frame. If the statistics obtained from the input divided frames are all available, at least one of light source control processing and image processing is performed using each statistics to project an image based on the target frame. To do. On the other hand, when the statistics corresponding to the predetermined number of divided frames before the target frame are not available, the light source control process and the image used when the image is projected based on the divided frame before the target frame. At least one of the processes is executed to project an image based on the target frame. The operation of projector 100 will be described in detail below.

FIG. 2 is a block diagram showing functional blocks of the projector 100 and the projection control device 200 included in the projection system.

The projector 100 has 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. These functional blocks are communicatively connected by an internal bus 111.

The CPU 101 is a control processor that controls each functional block of the projector 100. The CPU 101 is a programmable processor that realizes the operation of the projector 100 by reading a program stored in the ROM 103 into the RAM 102 and executing the program.

The RAM 102 is a storage medium used as a work memory when the CPU 101 executes a program. The RAM 102 stores a program, variables used for executing the program, and the like. Further, the RAM 102 may be used for other purposes (for example, as a data buffer).

The ROM 103 stores programs executed by the CPU 101, GUI data used for displaying menu screens, various setting values, and the like. The ROM 103 may be rewritable.

The projection unit 104 has a light source, a light source modulation element, a projection optical system, and the like, and projects an optical image based on the projection image supplied from the projection control unit 105. In this embodiment, a liquid crystal panel is used as an optical modulator, and the reflectance or transmittance of light from a light source is controlled according to the projection image to generate an optical image based on the projection image, and the projection optical system projects the projection surface. To project. In addition, the light source is controlled based on the control value obtained by the CPU 101 to change the brightness of the projected image.

The projection control unit 105 supplies the projection image data supplied from the image processing unit 109 to the projection unit 104.

The VRAM 106 is a video memory that stores a video signal supplied from the video input unit 110 or data of a projection image received from the outside (for example, a PC or a media player).

The operation unit 107 has input devices such as key buttons, switches, and a touch panel, and receives an instruction from the user to the projector 100. The CPU 101 monitors the operation of the operation unit 107, and when detecting the operation of the operation unit 107, executes the process according to the detected operation. When the projector 100 has a remote controller, the operation unit 107 notifies the CPU 101 of the operation signal received from the remote controller.

The network IF 108 is an interface that connects the projector 100 to a communication network, and has a configuration conforming to the standard of the communication network to be supported. In the present embodiment, the projector 100 is connected to the local network common to the projection control apparatus 200 via the network IF 108. Therefore, communication between the projector 100 and the projection control apparatus 200 is executed via the network IF 108.

The image processing unit 109 applies various image processing to the video signal stored in the VRAM 106 as necessary, and supplies the image signal to the projection control unit 105. The image processing unit 109 may be, for example, a microprocessor for image processing. Alternatively, the function corresponding to the image processing unit 109 may be realized by the CPU 101 executing a program stored in the ROM 103.

Image processing applicable to the image processing unit 109 includes frame thinning processing, frame interpolation processing, resolution conversion processing, projection image brightness control processing, contrast change processing, color adjustment processing, statistics acquisition processing, menu screens, and the like. The process includes, but is not limited to, a process of overlapping OSDs, a keystone correction process, an edge blending process, and the like.

The video input unit 110 is an interface that directly or indirectly receives a video signal output from an external device (projection control device 200 in the present embodiment), and has a configuration according to the supported video signal. The video input unit 110 is, for example, one of 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) terminal, and a DisplayPort (registered trademark) terminal. Including the above. When the video input unit 110 receives an analog video signal, the video input unit 110 converts the analog video signal into a digital video signal and stores the digital video signal in the VRAM 106.

Next, the functional configuration of the projection control apparatus 200 will be described. The projection control device 200 has a functional configuration based on a general-purpose computer. The projection control device 200 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. Also, the functional blocks of these are communicably connected by an internal bus 209.

The CPU 201 is a programmable processor, and implements the operation of the projection control apparatus 200 by reading a program (OS or application program) stored in the ROM 203 into the RAM 202 and executing the program, for example.

The RAM 202 is used as a work memory when the CPU 201 executes a program. The RAM 202 stores programs and variables used for executing the programs. The RAM 202 may be used for other purposes (for example, as a data buffer).

The ROM 203 may be rewritable. The ROM 203 stores programs executed by the CPU 201, GUI data used for displaying menu screens, various setting values, and the like. The projection control apparatus 200 may have a storage device (HDD or SSD) having a larger capacity than the ROM 203, and in this case, a large-capacity program such as an OS or an application program may be stored in the storage device.

The operation unit 204 has an input device such as a keyboard, a pointing device (mouse, etc.), a touch panel, a switch, etc., and receives an instruction from the user to the projection control apparatus 200. The keyboard may be a software keyboard. The CPU 201 monitors the operation of the operation unit 204, and when detecting the operation of the operation unit 204, executes the process according to the detected operation.

The display unit 205 is, for example, a liquid crystal panel or an organic EL panel. The display unit 205 displays screens provided by the OS and application programs. The display unit 205 may be an external device. Further, the display unit 205 may be a touch display.

The network IF 206 is an interface that connects the projection control apparatus 200 to a communication network, and has a configuration that conforms to the standards of the communication network that it supports. In the present embodiment, the projection control device 200 is connected to the local network common to the projector 100 via the network IF 206. Therefore, the communication between the projection control apparatus 200 and the projector 100 is executed through the network IF 206.

The video output unit 207 is an interface for transmitting a video signal to an external device (the projector 100 or the video distributor 300 in this embodiment), and has a configuration according to the video signal to be supported. The video output unit 207 includes, for example, one or more of 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) terminal.

The communication unit 208 is a communication interface for performing serial communication with an external device, typically a USB interface, but may have a configuration conforming to other standards such as RS-232C.

FIG. 3 is a diagram showing a flowchart executed by the CPU 101 of the projector 100 when the user starts multi-projection.

In this embodiment, multi-projection is performed using the three projectors 100a, 100b and 100c described in FIG. The number of connected projection devices is stored in the RAM 102 by the CPU 101 periodically monitoring the contents operated by the user using the operation unit 107 at an arbitrary timing. At this time, it is premised that the three projectors are time-synchronized in advance. The time synchronization may be set to a common time such as the world standard time, or may be set to a common time of only the connected device by communicating between the projectors. The multi-projection is started by a user's instruction obtained via the operation unit 107 or an instruction from an external device connected via the network IF 108. If either instruction is given, the multi-projection is started. When multi-projection is started by one unit, a start signal is transmitted to all the connected projectors, and multi-projection is started at the same time.

First, in step S300, the CPU 101 determines the predetermined frame number t1. The predetermined number of frames t1 is a time used to determine how many frames before the latest frame the statistic amount is used, and may be determined by the user's designation obtained through the operation unit 107. It may be determined by an instruction from an external device connected via the network IF 108, or a value stored in the ROM 103 in advance may be read. In this embodiment, the predetermined number of frames t1 is set to one frame.

In step S301, the CPU 101 acquires a statistic from the video input to the video input unit 110 via the image processing unit 109. The statistic in this embodiment is a frame average luminance in one frame. The statistic may be a distribution of average luminance for each partial area.

In step S302, the CPU 101 acquires the frame number t2 for which the statistic is acquired in step S301. In the present embodiment, the CPU 101 has a frame counter, and acquires the counter value when the statistic is acquired as the frame number. This frame counter is reset at the start of multi-projection. The frame number may be embedded in the video.

In step S303, the CPU 101 associates the statistic acquired in step S301 with the frame number t2 acquired in step S302, and stores the associated statistic and frame number t2 in the RAM 102. The storage location may be another storage location such as an external storage area.

In step S304, the CPU 101 reads out the statistic, the frame number t2, and the preset transmission source address associated in step S303 from the RAM 102 and transmits them to another projector through the network IF 108. Further, the statistic amount, the frame number t2 and the transmission source address transmitted from another projector are received and stored in the RAM 102.

In this embodiment, the projector 100a transmits/receives to/from the projector 100b and the projector 100c, the projector 100b to/from the projector 100a and the projector 100c, and the projector 100c to/from the projector 100a and the projector 100b through the network IF 108.

In step S305, the CPU 101 obtains the frame number t4 used for light source control and image processing. Specifically, the time t1 before the latest frame counter value t3 is set to t4.

In step S306, the CPU 101 reads the statistic received from another projector via the network IF 108 from the RAM 102, and there is a frame number t2 associated with the statistic and the frame number t4 obtained in step S305. To determine. If there is a match, the process proceeds to step S307. On the other hand, if there is no match, the process proceeds to step S309.

In step S307, the CPU 101 determines whether the statistic associated with the frame number t2 determined to match the frame number t4 in step S306 is the same as the number of connected units connected via the network IF 108.

In the present embodiment, when the CPU 101 determines that the statistics associated with the frame matching t4 are available for the number of connected units, it is determined that the statistics can be received. The determination of reception may be made by comparing the source address received from another projector with the address of another projector stored in the RAM 102 in advance to determine from which projector the information was transmitted. If it is determined that the reception is possible, the process proceeds to step S308, and if it is determined that the reception is not possible, the process proceeds to step S309.

In step S308, the CPU 101 calculates the statistic of the entire multi-screen based on the statistic of the number of connected devices associated with the frame matching t4, and performs light source control and image processing based on the statistic. In the present embodiment, the average value of the received statistic is set as the statistic of the entire multi-screen, and when the value is low, the light source is controlled to reduce the light amount, and the level of the image data is reduced in order to compensate for the decrease in brightness. By increasing the tone, it is possible to suppress black floating due to leaked light, and thus increase the contrast ratio. Note that any calculation method may be used for the calculation for determining the statistic amount of the entire multi-screen.

In step S309, the CPU 101 determines whether to end the multi projection. The end determination is performed according to a user's instruction obtained via the operation unit 107 or an instruction from an external device connected via the network IF 108, and the multi-projection is terminated if either instruction is given. When it is not determined that the process is ended, the process proceeds to step S301 and the processes of steps S301 to S309 are repeated.

FIG. 4 is a diagram illustrating a problem that occurs when the present invention is not applied.

Here, a process performed by the projector 100 for n frames and n+1 frames of a video signal will be described. Although representative statistics obtained by the n frames described on the projector 100a as the a _n, where statistics and the frame number is not associated.

The operation of the CPU 101 of the projector 100 in a certain frame is mainly to obtain a statistic amount, transmit the obtained statistic amount to another projector, receive a statistic amount from other constituent projectors, and obtain a statistic amount from all other constituent projectors. Is received, the frame is applied to the frame. In the present embodiment, the CPU 101 of the projector 100a acquires the statistic amount a _n , the CPU 101 of the projector 100b acquires the statistic amount b _n, and the CPU 101 of the projector 100c acquires the statistic amount cn in the n frames, and the CPU 101 of the projector 100c acquires the statistic amount c _n. Statistics are transmitted and received through the IF 108. Further, in the n+1 frame, the CPU 101 of the projector 100a acquires the statistic amount a _n+1 , the CPU 101 of the projector 100b acquires the statistic amount b _n+1 , the CPU 101 of the projector 100c acquires the statistic amount c _n+1, and the statistic amount is calculated through the network IF 108. Sending and receiving quantities.

At this time, in frame n, the projector 100a is statistics _{c n,} the projector 100b receives statistics _{c n} a statistic _{a n,} projector 100c delays sharing statistics like network latency, with n frames It is assumed that the statistics have not been received.

Further, in the n+1 frame, the projector 100a uses the statistics b _n and the statistics c _n+1 , the projector 100b uses the statistics a _n+1 and the statistics c _n+1 , and the projector 100c uses the statistics a _n and the statistics b _n in one frame. It is assumed that the reception is delayed.

Further, the received statistic is stored in the RAM 102, but since the statistic of each projection device is saved one by one, the statistic of each projection device is updated each time the statistic is received. Therefore, the latest statistics are always saved.

In such a state, when the light source control and the image processing based on the statistics are applied to the (n+1)th frame of the video input to the video input unit 110, the light source control and the image are processed based on the latest statistics of each projection device. Processing is performed. Therefore, in the projector 100a, the light source control and the image processing are performed based on the statistical amount a _n+1 , the statistical amount b _n+1, and the statistical amount c _n+1 .

Then, in the projector 100b, the light source control and the image processing are performed based on the statistic a _n+1 , the statistic b _n+1, and the statistic c _n+1 . Further, the projector 100c performs light source control and image processing based on the statistics a _n , the statistics b _n, and the statistics c _n+1 . Therefore, the statistic obtained from different frames is selected for each projection device and applied to the light source control and the image processing. Therefore, as shown in FIG. 5, the viewer may visually recognize it as a brightness difference between the plurality of display devices. There is.

FIG. 6 is a diagram for explaining that the problem is solved when the present invention is applied. The main processing is the same as in FIG. However, in FIG. 6, the statistic is associated with the frame number of the frame from which the statistic is acquired. Further, as described in step S300, the predetermined number of frames t1 is predetermined. In this embodiment, the predetermined number of frames t1 is one frame.

Further, in the present embodiment, similarly to the processing of the n frame and the n+1 frame described in FIG. 4, the CPU 101 of the projector 100a acquires the statistical amount a _n and the CPU 101 of the projector 100b acquires the statistical amount b _n in the n frame. Gets, CPU 101 of projector 100c acquires statistics _{c n,} and send and receive statistics through the network IF108 each other.

Further, in the n+1 frame, the CPU 101 of the projector 100a acquires the statistic amount a _n+1 , the CPU 101 of the projector 100b acquires the statistic amount b _n+1 , the CPU 101 of the projector 100c acquires the statistic amount c _n+1, and the statistic amount is calculated through the network IF 108. Sending and receiving quantities. This corresponds to steps S301 to S304.

At this time, in frame n, the projector 100a is statistics _{c n,} the projector 100b receives statistics _{c n} a statistic _{a n,} a projector 100c is not received statistics. In the n+1 frame, the projector 100a receives the statistics b _n and the statistics c _n+1 , the projector 100b receives the statistics a _n+1 and the statistics c _n+1 , and the projector 100c receives the statistics a _n and the statistics b _n. Suppose

Note that, unlike FIG. 4, since the statistic and the frame number are associated with each other, the statistic that has not been used is not erased and is stored in the RAM 102.

In such a state, the light source control and the image processing based on the statistics are applied to the (n+1)th frame of the image input to the image input unit 110. First, of the frame numbers stored in the RAM 102, a predetermined frame number t1 (1 frame) before the latest frame counter value n+1, that is, a statistic having a frame number matching t4 corresponds to all projectors including the own projector. Determine if they are complete. This corresponds to steps S306 and S307.

Then, when it is determined that they are aligned, light source control and image processing are performed based on the statistic. In this embodiment, in order to prevent the light source control and the image processing based on the statistic different for each projector, the average statistic of the statistic a _n , the statistic b _n, and the statistic c _n is set in the projector 100. Light source control and image processing are performed based on the light source control.

If it is determined that they are not aligned, the light source control and the image processing are performed based on the statistic used last time.

By performing this series of processing, the light source control and the image processing based on the statistics acquired from the same frame can be applied to each projection device. Therefore, if the delay in sharing the statistics is within a predetermined frame, a plurality of display devices are displayed. It is possible to eliminate the brightness difference that appears between the two.

<Practical example 2>
Next, a second embodiment of the present invention will be described.

In the first embodiment, the difference between the frame number of the statistic used and the latest frame number is a fixed value, but in the second embodiment, the difference is not a fixed value but is dynamically changed. Different from 1.

FIG. 7 is a diagram showing a flowchart executed by the CPU 101 of the projector 100 when the user starts multi-projection.

In step S700, the CPU 101 sets the predetermined frame number t1 as the first delay value. The predetermined number of frames t1 is a time used to determine how many frames before the latest frame the statistic amount is used, and may be determined by the user's designation obtained through the operation unit 107. It may be determined by an instruction from an external device connected via the network IF 108, or a value stored in the ROM 103 in advance may be read. In this embodiment, the predetermined number of frames t1 and the first delay value are set to one frame.

Since steps S701 to S704 are equivalent to steps S301 to S304, the description thereof will be omitted.

In step S705, the CPU 101 obtains the frame number t4 used for light source control and image processing. Specifically, the time t1 before the latest frame counter value t3 is set to t4.

In step S706, the CPU 101 reads the statistic received from the other projector via the network IF 108 from the RAM 102, and the frame number t2 associated with the statistic matches the frame number t4 obtained in step S705. It is determined. If there is a match, the process proceeds to step S707. On the other hand, if there is no match, the process proceeds to step S709.

In step S707, the CPU 101 determines whether the statistic associated with the frame number t2 determined to match the frame number t4 in step S706 is the same as the number of connected units connected via the network IF 108.

If it is determined that the reception is possible, the process proceeds to step S708, and if it is determined that the reception is not possible, the process proceeds to step S709.

In step S708, the CPU 101 calculates the statistic of the entire multi-screen based on the statistic of the number of connected units associated with the frame matching t4, and performs the light source control and the image processing based on the statistic.

In step S709, the CPU 101 updates the first delay value. Details of this step will be described with reference to FIG.

Since step S710 is equivalent to step S309, description thereof will be omitted.

FIG. 8 is a flowchart showing the first delay value updating process.

In step S800, the CPU 101 stores the frame number t4 acquired in step S705 in the memory area for updating the first delay amount (hereinafter referred to as F area) in order to determine the statistic amount of the entire multi-screen. In the present embodiment, the RAM 102 is the F area, but it may be another storage area such as an external storage area.

In step S801, the CPU 101 determines whether or not some frame numbers stored in the F area have not been subjected to the determination in step S802. If there is an item that has not been determined in step S802, the process proceeds to step S802, and if not, the process proceeds to step S808.

In step S802, the CPU 101 reads, from the RAM 102, the frame number determined in step S801 that has not been determined in step S802 among the statistic amount stored in step S703 and the frame number stored in the F area, It is determined whether or not the statistic associated with the frame number exists for the number of connected devices. Then, if it is determined that the number of connected vehicles exists, the process proceeds to step S803, and if it is determined that there is no connected device, the process returns to step S801.

In order to explain this determination method in detail, how the frame number stored in the RAM 102 in the n frame and n+1 of the projector 100a, the statistic, and the frame number stored in the F area change will be described.

First, in n frames, the statistics a _n and the statistics c _n are stored in the RAM 102 as shown in FIG. 9A. At this time, the statistics a _n and the statistics c _n are associated with the frame number n.

Next, in the (n+1)th frame, the statistic a _n+1 , the statistic b _n, and the statistic c _n+1 are stored in the RAM 102 as shown in FIG. 9B. At this time, the statistic a _n+1 and the statistic c _n+1 are associated with the frame number n+1, and the statistic b _n is associated with the frame number n. The frame number n, which is before the first delay value of n+1 frames, is stored in the F area.

When the determination in step S802 is performed in such a state, first, it is determined whether or not the statistic associated with the frame number n stored in the F area is present in the RAM 102 for the number of connected devices. Here it is determined that three Statistics Statistics a _n, b _n and c _n is because it is associated with the frame number n, there the number of connected component, the process proceeds to step 803.

In step S803, the CPU 101 sets the frame number associated with the statistic determined to exist for the number of connected vehicles in step S802 to t5, sets the value obtained by subtracting t5 from t3 acquired in step S705 as the second delay value, and stores it in the RAM 102. save. In this embodiment, the second delay value is the number of frames required to receive the statistics of all PJs.

In step S804, the CPU 101 deletes the frame number t5 from the F area. Also, the statistic of the entire multi-screen is obtained from the statistic that exists for the number of connected devices and stored in another area. Then, the used statistic is deleted from the RAM 102. At this time, the frame number stored in the RAM 102, the statistic amount, and the frame number stored in the F area in the (n+1)th frame of the projector 100a described in step S802 change as shown in FIG. 9C.

In step S805, the CPU 101 reads the first delay value and the second delay value from the RAM 102 and determines whether the second delay value is larger than the first delay value. If it is determined that the second delay value is larger, the process proceeds to step S806, and if it is determined that the first delay value is larger, the process proceeds to step S801.

In step S806, the CPU 101 transmits the second delay value calculated in step S803 to another projector via the network IF 108. In addition, the second delay value transmitted from another projector is received and stored in the RAM 102.

In step S807, the CPU 101 updates the first delay value with the second delay value and saves it in the RAM 102.

In step S808, the CPU 101 reads the second delay value received from another projector via the network IF 108 from the RAM 102, and determines whether or not the determination in step S809 has not been performed. If there is any that has not been determined in step S809, the process proceeds to step S809, and if not, the first delay value updating process ends.

In step S809, the CPU 101 reads the first delay value and the second delay value received from another projector via the network IF 108 from the RAM 102, and determines whether the second delay value is larger than the first delay value. If it is determined that the second delay value is larger, the process proceeds to step S810, and if it is determined that the first delay value is larger, the process proceeds to step S808. In step S810, the CPU 101 sets the first delay value to the second value. Update with delay value. As a result, the maximum delay value is shared by all the constituent projectors, and it is possible to improve the deviation in the application timing of light source control and image processing. Then, the process proceeds to step S808.

FIG. 10 is a diagram illustrating the second delay value when the first delay value is updated in the second embodiment. Here, the statistic obtained by the projector 100 in the nth frame, the n+1th frame, and the n+2th frame of the input video signal will be described.

In the present embodiment, the CPU 101 of the projector 100a acquires the statistic amount a _n , the CPU 101 of the projector 100b acquires the statistic amount b _n, and the CPU 101 of the projector 100c acquires the statistic amount cn in the n frames, and the CPU 101 of the projector 100c acquires the statistic amount c _n. Statistics are transmitted and received through the IF 108.

Further, in the n+1 frame, the CPU 101 of the projector 100a acquires the statistic amount a _n+1 , the CPU 101 of the projector 100b acquires the statistic amount b _n+1 , the CPU 101 of the projector 100c acquires the statistic amount c _n+1, and the statistic amount is calculated through the network IF 108. Sending and receiving quantities.

Further, in the n+2 frame, the CPU 101 of the projector 100a acquires the statistic amount a _n+2 , the CPU 101 of the projector 100b acquires the statistic amount b _n+2 , the CPU 101 of the projector 100c acquires the statistic amount cn _+2, and the statistic amount c _n+2 is acquired through the network IF 108. Sending and receiving quantities.

At this time, in frame n, the projector 100a is statistics _{c n,} the projector 100b receives statistics _{c n} a statistic _{a n,} a projector 100c is not received statistics.

It is also assumed that the projector 100a receives the statistics b _n and the statistics c _n+1 , the projector 100b receives the statistics a _n+1 and the statistics c _n+1 , and the projector 100c receives the statistics a _n in the n+1 frame.

Then, in the n+2 frame, the projector 100a receives the statistics b _n+1 and the statistics c _n+2 , the projector 100b receives the statistics a _n+2 and the statistics c _n+2 , and the projector 100c receives the statistics a _n+1 and the statistics b _n. Suppose

In such a state, the statistics of n frames are all collected in the n+1th frame of the projector 100a, the nth frame of the projector 100b, and the n+2th frame of the projector 100c. Therefore, the second delay value of the projector 100a is (n+1)-n for 1 frame, the second delay value of the projector 100b is n-n for 0 frames, and the second delay value of the projector 100c is (n+2)-n for 2 frames. It becomes a frame. The second delay value acquired by each projector is transmitted to each projector via the network IF 108.

Each projector selects the value with the largest delay among the second delay values and updates the first delay value with that value. In this embodiment, the maximum second delay value is 2 frames of the projector 100c, and the first delay value is 2 frames.

By performing this series of processing, even if the delay in sharing the statistic is a predetermined frame or more, the light source control and the image processing based on the statistic acquired from the same frame can be applied to each projection device, so that a plurality of display images can be displayed. It is possible to eliminate the brightness difference that appears between devices.

<Other Examples>
Needless to say, the object of the present invention can be achieved by supplying a storage medium storing a program code of software that realizes the functions of the above-described embodiments to an apparatus. At this time, the computer (or CPU or MPU) including the control unit of the supplied device reads and executes the program code stored in the storage medium.

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

As the 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 non-volatile memory card, a ROM or the like can be used.

An OS (basic system or operating system) running on the device performs some or all of the processing based on the instructions of the above-described program code, and the processing realizes the functions of the above-described embodiments. It goes without saying that cases are included.

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

100 projector, 101 CPU, 102 RAM, 103 ROM,
104 projection unit, 105 projection control unit, 106 VRAM, 107 operation unit,
108 network IF, 109 image processing unit, 110 video input unit,
200 projection control device, 201 CPU, 202 RAM, 203 ROM,
204 operation unit, 205 display unit, 206 network interface,
207 video output unit, 208 communication unit, 209 internal bus, 300 video distributor

Claims (2)

A system including a plurality of display devices,
Each display device
Video input means,
A predetermined frame number determining means for determining the predetermined frame number;
A statistic amount acquisition unit for acquiring a statistic amount from the image input by the image input unit;
Frame number acquisition means for acquiring the frame number of the frame for which the statistic is acquired,
Association means for associating the frame number with the statistic;
Recording means for recording the associated frame number and the statistic,
Communication means for communicating the frame number and the statistic associated with another display device,
The latest frame acquisition means to acquire the latest frame,
A used frame number acquisition means for acquiring a frame number of the predetermined number of frames before the latest frame;
Matching determination means for determining whether the frame number received from another display device by the communication means and the frame number recorded in the own display device by the recording means match the frame number of the used frame,
Reception determination means for confirming whether or not the statistics associated with the frame numbers determined to match by the coincidence determination means are available for the number of connected devices,
Calculation means for calculating one statistic based on the statistic for the number of connected vehicles determined to be complete by the reception determination means;
Video display means for displaying video,
Equipped with
When it is determined that the coincidence is determined by the coincidence determination unit, and when the reception determination unit determines that they are aligned, light source control and image processing are performed based on the statistic calculated by the calculation unit, and the coincidence is performed. A system that performs light source control and image processing based on the statistic used last time when the determination unit determines that they do not match or the reception determination unit determines that they do not match. With the predetermined number of frames as the first delay value, the number of frames from the frame for which the statistics is acquired by the self-display device to the frame for which the statistics associated with the frame number of the frames are the same as the number of connected frames. Second delay value calculating means for calculating two delay values;
Delay amount determining means for determining the delay amount,
Updating means for updating the first delay value,
Equipped with
The frame number, the statistic, and the second delay value associated with each other are transmitted and received by the communication unit,
The delay amount determining means selects the maximum second delay value from the received second delay value and the second delay value acquired by the self display device,
The system according to claim 1, wherein the updating means updates the first delay value with the maximum second delay value when the maximum second delay value is larger than the first delay value.