WO2020162051A1

WO2020162051A1 - Projection type video display system

Info

Publication number: WO2020162051A1
Application number: PCT/JP2019/049517
Authority: WO
Inventors: 田中　和彦; 中嶋　満雄
Original assignee: マクセル株式会社
Priority date: 2019-02-06
Filing date: 2019-12-18
Publication date: 2020-08-13
Also published as: JP2020127162A

Abstract

In a projection type video display system 10, geometric correction circuits 25 of projectors 11-14 correct geometric distortions in videos to be projected on the basis of geometric parameters. A personal computer 16 includes a camera video analysis unit 33 that: calculates coordinates for each of four corner parts in a video projected by each of the projectors 11-14 and photographed by the camera 15; compares the calculated coordinates with a pre-set threshold; and determines that a time lag is occurring when the coordinates exceed the threshold. The geometric correction circuits 25 correct the videos projected by the projectors 11-14 when the camera video analysis unit 33 has determined that a time lag is occurring.

Description

Projection type video display system

The present invention relates to a projection-type image display system, and more particularly to a technique effective for correcting image distortion in image projection using a plurality of projectors.

Demand for high brightness has increased in recent years in projectors that display large screen images. As a projection technique for increasing the brightness of a display image, there is so-called stack projection in which, for example, a plurality of projectors are used to perform superimposed projection.

When performing this stack projection, it is necessary to install multiple projector images with pixel accuracy when installing the projector. In this work, for example, an adjustment pattern image projected from each projector is photographed by a camera or the like, and geometric correction is performed based on the photographed image.

Note that, as a technique for correcting a projected image using a plurality of projectors of this type, when forming a projection region in which at least a part of the projection region is superimposed using the plurality of projectors, the shape of the projection region There is one that corresponds to the shape of the content image (see Patent Document 1, for example).

Japanese Patent Laid-Open No. 2018-125819

In the above-mentioned projector stack projection, even if the images are superimposed pixel by pixel when the projector is installed, there is a risk that the superimposed images will shift over time, or time lag will occur.

-The cause of the time lag is that the projector moves due to vibrations, so-called misalignment, or screen misalignment. In order to correct this time lag, it is necessary to periodically project the adjustment pattern again to perform geometric correction, which requires time and man-hours each time.

Also, even if the correction is performed regularly, if the correction interval becomes long, it is possible that the image shift occurs when the image is projected. In that case, there is a problem that the shifted image continues to be projected, and the sharpness of the image decreases.

An object of the present invention is to provide a technique capable of automatically detecting and correcting image distortion when projecting image content and eliminating the need for periodic image correction after the projector is installed. It is in.

The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

Among the inventions disclosed in the present application, a brief description of the outline of typical ones is as follows.

That is, a typical projection-type video display system includes a plurality of projectors, a computer, and an imaging unit. The plurality of projectors project an image. The computer outputs the video data to the plurality of projectors. The imaging unit captures an image projected by the plurality of projectors on the image projection surface (.

A plurality of projectors have a geometric correction unit and a video projection unit. The geometric correction unit corrects the geometric distortion of the projected image based on the geometric parameter. The image projection unit projects an image on the image projection surface.

The computer has a video analysis unit and a control unit. The image analysis unit analyzes the image captured by the image capturing unit and determines whether or not there is a time-dependent shift that causes a shift in the images projected by the plurality of projectors. The control unit controls the plurality of projectors.

Then, the video analysis unit calculates the coordinates of the four corners of the video projected by each projector captured by the imaging unit, compares the calculated coordinates with a preset threshold, and calculates the coordinates. Is above the threshold value, it is determined that a time lag has occurred.

The geometric correction unit corrects the image projected by each projector when the image analysis unit determines that a time lag has occurred.

Also, when the imaging unit captures the image of each projector, the control unit projects only the image of the projector that is the target of coordinate calculation, and dims the corners of the projector that is not the target.

The effects obtained by the representative ones of the inventions disclosed in the present application will be briefly described as follows.

It is possible to eliminate the need to periodically correct the projected image after installing the projector.

FIG. 3 is an explanatory diagram showing an example of an external appearance of the projection type video display system according to the first embodiment. It is explanatory drawing which shows an example of a structure in the projection type video display system of FIG. It is explanatory drawing which shows an example of the image which the projector of FIG. 1 projects. It is explanatory drawing which shows an example of the image|video when the projector of FIG. 1 carries out stack projection. 3 is a flowchart showing an example of an outline of overall processing by the projection type video display system of FIG. 2. 6 is a flowchart showing an example of a process in initial adjustment which is the process of step S101 of FIG. It is explanatory drawing which shows an example of the projection image of the all-white image by the projector of FIG. It is explanatory drawing which shows an example of calculation in the display area by initial adjustment. 6 is a flowchart showing an example of a process in time-dependent shift detection which is the process of step S103 of FIG. It is explanatory drawing which shows an example of a time-dependent shift detection of FIG. FIG. 3 is an explanatory diagram showing an example of calculation of coordinates of a corner portion in correction of time-dependent shift by the projection type image display system of FIG. 2. 12 is a flowchart showing an example of processing in time-dependent shift correction using the coordinate calculation example of FIG. 11. FIG. 9 is an explanatory diagram showing an example of calculation of coordinates of a corner portion in correction of time-dependent deviation according to the second embodiment. 14 is a flowchart showing an example of a process of time-dependent shift correction using the coordinate calculation example of FIG. 13. FIG. 11 is an explanatory diagram showing an example of calculating coordinates of a corner portion according to the third embodiment. It is explanatory drawing which shows the other example of FIG. FIG. 16 is an explanatory diagram showing an example of calculating the coordinates of a corner portion in the correction of time-dependent deviation according to the fourth embodiment. 16 is a flowchart showing an example of an outline of overall processing in the projection type video display system according to the fifth embodiment. It is explanatory drawing which shows an example of the image content in which the time-dependent shift occurred. FIG. 16 is an explanatory diagram showing an example of a configuration of a projection type video display system according to a sixth embodiment. FIG. 16 is an explanatory diagram showing an example of a configuration of a projection type video display system according to a seventh embodiment. FIG. 19 is an explanatory diagram showing an example of a configuration of a projection type video display system according to an eighth embodiment.

In all the drawings for explaining the embodiments, the same reference numerals are given to the same members in principle, and the repeated description thereof will be omitted.

The following describes the embodiment in detail.

(Embodiment 1)
<Example of appearance of projection type video display system>
FIG. 1 is an explanatory diagram showing an example of the external appearance of a projection-type image display system 10 according to the first embodiment.

As shown in FIG. 1, the projection-type image display system 10 includes projectors 11 to 14, a camera 15, and a personal computer 16. The projection-type image display system 10 performs stack projection for realizing high brightness by superimposing images projected from the projectors 11 to 14.

The projectors 11 to 14 irradiate the image data input from the outside to the image projection surface such as the wall surface or the screen 50, which is the projection target. The camera 15, which is an image capturing unit, captures an image projected on the screen 50.

The projectors 11 to 14 and the camera 15 are connected to a personal computer 16 which is a computer. The personal computer 16 outputs the video data to the projectors 11 to 14, respectively.

Here, FIG. 1 shows an example in which images projected from four projectors 11 to 14 are superimposed and projected, but the number of projectors to perform stack projection is not particularly limited as long as it is two or more. ..

<Configuration example of projection type video display system>
FIG. 2 is an explanatory diagram showing an example of the configuration of the projection type video display system 10 of FIG.

The projector 11 includes a video interface 20, a marker generation circuit 21, a mask generation circuit 22, a pattern generation circuit 23, a video calculation circuit 24, a geometric correction circuit 25, a geometric correction parameter storage unit 26, an optical system 27, a communication interface 28, and control. It is composed of a circuit 29.

Note that, in FIG. 2, the configuration of the projectors 12 to 14 is the same as that of the projector 11, and thus the description thereof is omitted. These projectors 11 to 14 have an adjusting function of adjusting the deviation of the image captured by the camera 15 in the stack projection.

The video interface 20 is an interface for transmitting video data output from the personal computer 16, and is connected to the personal computer 16 via, for example, an HDMI (High Definition Multimedia Interface) terminal.

The marker generation circuit 21, which is a marker generation unit, generates a marker, a frame-shaped white frame, or the like under the control of the control circuit 29. The marker or the white frame is used for adjusting the image shift in the stack projection. The marker is displayed at the corner of the projected image. The white frame is displayed around the projected image.

The mask generation circuit 22, which is a mask generation unit, generates a mask. The mask adjusts the brightness of the corner portion of the image projected on the screen 50. The pattern generation circuit 23 generates a correction pattern.

The video calculation circuit 24 synthesizes the marker generated by the marker generation circuit 21 with the projected image, synthesizes the mask generated by the mask generation circuit 22 with the projected image, or displays all white generated by the pattern generation circuit 23. The correction pattern such as an image or an all-black image is displayed.

The marker generation circuit 21, the mask generation circuit 22, the pattern generation circuit 23, and the video calculation circuit 24 operate under the control of the control circuit 29. The geometric correction circuit 25, which is a geometric correction unit, corrects the projected image by geometrically correcting the geometric distortion of the projected image based on the geometric parameter.

The geometric correction parameter storage unit 26 is a non-volatile memory such as a flash memory, for example, and stores geometric parameters calculated by a parameter calculation unit 34 described later. The geometric correction circuit 25 geometrically corrects the geometric distortion of the projected image based on the geometric parameters stored in the geometric correction parameter storage unit 26. The communication interface 28 is an interface for communicating with the projectors 11 to 14.

The optical system 27, which is a video projection unit, converts the video data geometrically converted by the geometric correction circuit 25 into light and projects it. The optical system 27 includes, for example, a projection lens that projects an image on the screen 50, a display element that generates the projected image, and a light source unit that generates illumination light for projection.

As the display element, for example, a DMD (Digital Micromirror Device) (registered trademark) panel or the like is used.

The display element is not limited to the DMD panel, and may be, for example, a transmissive liquid crystal panel or a reflective liquid crystal panel. The control circuit 29 controls the operation of the projector 11.

The personal computer 16 includes a camera input unit 30, a projection video selection unit 31, a video transmission unit 32, a camera video analysis unit 33, a parameter calculation unit 34, a communication control unit 35, a projection video generation unit 36, a projection video analysis unit 37, and a storage. It is composed of a unit 38 and a sequence control unit 39.

The camera input unit 30 acquires image data captured by the camera 15 via, for example, a USB (Universal Serial Bus) terminal. The projected image selection unit 31 determines a correction pattern to be used for correcting the projected image and sends it to the control circuits 29 of the projectors 11 to 14, respectively.

The video transmission unit 32 transmits the video data generated by the projection video generation unit 36 to the projectors 11-14.

The camera image analysis unit 33, which is an image analysis unit, analyzes the image captured by the camera 15 and detects the corner portion of the projected image. The parameter calculator 34 calculates a geometric parameter for correcting the geometric distortion of the projected image.

The communication control unit 35 communicates with the control circuit 29 included in the projectors 11 to 14. The projection video generation unit 36 decodes the video content stored in the storage unit 38. The decoded video content is output to the projection video generation unit 36.

The projected image analysis unit 37 analyzes the image data transmitted by the image transmission unit 32, that is, the image projected by the projector, and determines whether or not the corner portion of the projected image can be detected. The storage unit 38 is composed of, for example, a hard disk drive (HDD) or a non-volatile memory such as a flash memory, and stores video content to be projected on the screen 50. The sequence control unit 39 serving as a control unit controls the operation in the correction process of the projected image.

<Example of stack projection image>
FIG. 3 is an explanatory diagram showing an example of an image displayed on the screen 50 when the projectors 11 to 14 in FIG. 1 project an image “A” without performing geometric correction. FIG. 4 is an explanatory diagram showing an example of an image when the projectors 11 to 14 of FIG. 1 perform stack projection.

FIG. 3A shows a state in which the image of “A” projected by the projector 11 is displayed on the screen 50, and FIG. 3B shows the image of “A” projected by the projector 12 and FIG. 3A shows a state of the image of “A” projected by the projector 13 and FIG. 3D shows a state of the image of “A” projected by the projector 14 on the screen 50.

Since the installed positions of the projectors 11 to 14 are different from each other, as shown in FIGS. 3A to 3D, even when the same image without distortion is projected. However, the image projected on the screen 50 is distorted according to the installation position.

When the distortion is not corrected and is displayed on the screen 50 as it is, as shown in FIG. 4A, the character “A” displayed on the screen 50 is misaligned and displayed unclearly as shown in FIG. 4A. To be done.

In the projection type video display system 10, before correction, that is, a rectangular area is determined from the display area of each projector shown in FIG. 4A, and geometric conversion is performed so as to match the determined rectangular area, and the images are superimposed. The projection-type image display system 10 also has a function of automatically correcting a time-dependent shift in which superimposed images shift with time.

As a result, as shown in FIG. 4B, the deviation of the image of “A” projected from each of the projectors 11 to 14 is reduced, and a clear image can be displayed on the screen 50 even in an environment where a time-dependent deviation occurs. Can be displayed on.

<Operation example of projection type video display system>
Next, the operation of the projection type image display system 10 will be described.

FIG. 5 is a flowchart showing an example of the outline of the overall processing by the projection type video display system 10 of FIG.

The processing of each step in FIG. 5 is executed by each functional block as described below, but the function may be realized by software. In that case, it is realized by the sequence control unit 39, the control circuit 29 and the like executing software in a program format stored in a program storage memory (not shown) of the personal computer 16 or the projectors 11 to 14, respectively.

First, perform initial adjustment (step S101). This initial adjustment is performed only when the projection-type image display system 10 is initially installed. In the process of step S101, after the projectors 11 to 14 are installed, the deviation of the projected image displayed on the screen 50 is adjusted.

After that, the projection of the video content by the projectors 11 to 14 is started (step S102). Then, while the video content is being projected, a time-lapse detection process for detecting the occurrence of time-lapse is executed (step S103).

In the time shift detection process, when it is detected that a time shift has occurred (step S104), a time shift correction process for correcting the time shift by the projection-type image display system 10 is performed (step S105).

If it is not detected in the process of step S104 that a time lapse has occurred, or if the process of correcting the time lapse by the process of step S105 ends, the process returns to step S102.

<About initial adjustment>
Next, the initial adjustment will be described with reference to FIG.

FIG. 6 is a flowchart showing an example of processing in the initial adjustment which is the processing of step S101 in FIG.

First, the sequence control unit 39 sets the target projector number, which is a variable held in the projected image selection unit 31, to 0 (step S201). Subsequently, the sequence control unit 39 issues a command for projecting an all-white image to the control circuit 29 of the target projector (for example, the projector 11) via the communication control unit 35 according to the target projector number (step S202).

The control circuit 29 receiving the command from the sequence control unit 39 controls the pattern generation circuit 23 to generate an all-white image. The all-white image generated by the pattern generation circuit 23 is projected by the optical system 27 via the image calculation circuit 24 and the geometric correction circuit 25.

After that, the sequence control unit 39 issues a command for projecting an all-black image to the control circuit 29 of the projector (eg, projectors 12 to 14) other than the target projector via the communication control unit 35 according to the target projector number ( Step S203).

In the process of step S203, the control circuit 29 having received the command causes the pattern generation circuit 23 to generate an all-black image. The all-black image generated by the pattern generation circuit 23 is projected by the optical system 27 via the image calculation circuit 24 and the geometric correction circuit 25.

When the process of step S203 is completed, the sequence control unit 39 waits for the waiting time defined in advance (step S204). The waiting time is defined based on, for example, a time +margin from when a command is issued to each projector to when the projected image is actually reflected.

Then, the sequence control unit 39 issues a shooting command to the camera 15 via the camera input unit 30. Upon receiving this command, the camera 15 shoots a screen (step S205).

The camera 15 sends the captured image to the camera input unit 30. The camera input unit 30 stores the input video in an internal buffer (not shown) provided in the camera input unit 30, and when the storage of the video is completed, transmits a shooting completion signal to the sequence control unit 39.

The sequence control unit 39, when receiving the photographing completion signal from the camera input unit 30, issues a video analysis instruction command to the camera video analysis unit 33. Upon receiving the command from the sequence control unit 39, the camera image analysis unit 33 receives the captured image from the internal buffer of the camera input unit 30, and detects the four corners of the display region of the projected image including the received camera image. The coordinates are calculated (step S206).

When the calculation of the coordinates of the corner portion in the projected image is completed, the camera image analysis unit 33 notifies the sequence control unit 39 that the calculation is completed. Upon receiving the calculation end notification, the sequence control unit 39 stores the calculated four corner coordinates for each target projector number.

The calculated coordinates may be stored in, for example, a storage area (not shown) of the camera image analysis unit 33, or the calculated coordinates may be stored in the storage unit 38.

When the process of step S206 ends, the sequence control unit 39 increments the target projector number, which is a variable held in the projected image selection unit 31, by 1 (step S207).

If the target projector number is smaller than the number of projectors (step S208), the sequence control unit 39 returns to the beginning of the loop and repeats the processing from step S202. If the processing of all projectors is completed (step S208), the geometric parameter calculation processing is executed (step S209).

In the process of step S209, the sequence control unit 39 issues a geometric conversion parameter calculation command to the parameter calculation unit 34. Upon receiving the command from the sequence control unit 39, the parameter calculation unit 34 reads out the coordinates of the corner unit stored for each target projector in a storage area (not shown) of the camera image analysis unit 33 and corresponds to each of the projectors 11 to 14. The calculated geometric transformation matrix is calculated.

When all the geometric transformation matrices are obtained, the camera image analysis unit 33 notifies the sequence control unit 39 of the completion. Upon receiving the completion notification, the sequence control unit 39 transmits the geometric conversion matrix to the control circuit 29 of each of the projectors 11-14.

Upon receiving the geometric transformation matrix, the control circuit 29 of the projectors 11 to 14 stores the received geometric transformation matrix in the geometric correction parameter storage unit 26, and stores it in the geometric correction parameter storage unit 26 for the geometric correction circuit 25. The geometric transformation is executed using the parameter, that is, the geometric transformation matrix. Further, the control circuit 29 sets the video arithmetic circuit 24 to output the signal output from the video interface 20.

By making these settings, each of the projectors 11 to 14 performs the geometric conversion on the video input from the video interface 20 based on the geometric conversion parameter stored in the geometric correction parameter storage unit 26. Project the converted video.

When the projection video generation unit 36 receives the content reproduction instruction from the sequence control unit 39, the projection video generation unit 36 reads the video content from the storage unit 38 based on the preset content name, and decodes the read video content. And generate video data.

The projection video generation unit 36 sends the generated video data to each of the projectors 11 to 14 via the communication control unit 35. The projection image generation unit 36 realizes moving image reproduction by executing the above processing and updating the image at a frame cycle corresponding to the content, for example, every 30 frames/second. Further, a frame synchronization signal is sent to the sequence controller 39 each time the processing of each frame is completed.

Here, the calculation processing of the geometric transformation matrix by the parameter calculation unit 34 will be described.

When projecting an image with a projector or shooting with the camera 15, the image is transformed based on a transformation called perspective transformation. By performing perspective transformation, near objects are displayed large and objects far away are displayed small as in the real world.

When the point (xi, yi) in one coordinate system is converted to the point (xo, yo) in another coordinate system by the perspective transformation, the relationship of Equation 1 is established between them.

This equation is written in homogeneous coordinates, and xo and yo can be obtained by the following equations 2 and 3.

The 3×3 matrix in Expression 1 is a transformation matrix that defines the perspective transformation. This conversion matrix can be specified by obtaining eight variables a00 to a21 which are elements of the matrix. Eight equations are required to obtain eight unknowns, and for that purpose, it is only necessary to know four pairs of (xi, yi) and (xo, yo).

That is, it is possible to obtain the transformation matrix by knowing which coordinate the four coordinates on the image before perspective transformation are respectively transformed. Here, this is used to calculate the geometric transformation matrix.

<Coordinate calculation example>
Next, an example of calculating the coordinates of the four corner portions in the image after correction by the geometric conversion matrix will be described. Note that, here, for simplicity of description, it is assumed that images are projected from the two

projectors

11 and 12.

FIG. 7 is an explanatory diagram showing an example of a projected image of an all-white image by the

projectors

11 and 12 of FIG.

FIG. 7A shows the shape of the all-white image 51 projected onto the screen 50 by the projector 11, and the camera 15 photographs the all-white image 51 projected onto the screen 50 by the camera 15.

Similarly, FIG. 7B shows the shape of the all-white image 52 projected by the projector 12 on the screen 50, and shows the all-white image 52 projected by the projector 12 on the screen 50 by the camera 15. Is.

Here, the vertices of the four corner portions of the all-white image 51 are points A0, B0, C0, and D0, respectively, as shown in FIG. 7A, and the vertices of the four corner portions of the all-white image 52 are As shown in FIG. 7B, points A1, B1, C1, and D1 are set, respectively.

The display area of the corrected image 53 is determined by obtaining the points Am, Bm, Cm, and Dm that are the vertices of the four corners of the corrected image 53 using the all-

white images

51 and 52 of FIG. ..

<Display area calculation example>
FIG. 8 is an explanatory diagram showing an example of calculation in the display area by the initial adjustment.

In FIG. 8, the all-white image 51 of FIG. 7A and the all-white image 52 of FIG. 7B are shown by dotted lines, and the corrected image 53 is shown by solid lines.

First, the X-coordinates of points A0 and D0 of the all-white image 51 and points A1 and D1 of the all-white image 52 are obtained with the corner portion at the lower left corner of the screen 50 in FIG. 8 as the origin. Among the obtained X coordinates of the points A0 and D0 and the points A1 and D1, the X coordinate of the point having the maximum value is set as the X coordinate of the point Am and the point Dm, respectively.

Similarly, the X-coordinates of the points B0 and C0 of the all-white image 51 and the points B1 and C1 of the all-white image 52 are obtained, respectively, which is the minimum value among the obtained X-coordinates of the points B0 and C0 and the points B1 and C1. The X coordinates of the points are set as the X coordinates of the points Bm and Cm, respectively.

Then, the Y coordinates of the points A0 and B0 of the all-white image 51 and the points A1 and B1 of the all-white image 52 are obtained, respectively, which is the maximum value among the obtained Y coordinates of the points A0 and B0 and the points A1 and B1. The Y coordinates of the points are set as the Y coordinates of the points Am and Bm, respectively.

Similarly, the Y coordinates of the points D0 and C0 of the all-white image 51 and the points D1 and C1 of the all-white image 52 are obtained, respectively, which is the maximum value among the obtained Y coordinates of the points D0 and C0 and the points D1 and C1. The Y coordinate of the point is set as the Y coordinate of the point Dm and the point Cm, respectively.

The rectangular area having the corners of the points Am, Bm, Cm, and Dm thus obtained is used as the display area of the corrected image 53.

<Example of detection of time lag>
Next, the operation of detecting the time shift by the projection type image display system 10 will be described.

FIG. 9 is a flowchart showing an example of the process in the time shift detection which is the process of step S103 of FIG.

The process shown in FIG. 9 is performed mainly by the camera image analysis unit 33 of FIG. The sequence control unit 39 is assumed to execute the processing shown in FIG. 9 for each frame synchronization signal output from the projection image generation unit 36. The frame synchronization signal is output, for example, every 30 frames.

First, frame superimposition processing of camera images is performed (step S301). In the process of step S301, when the sequence control unit 39 receives the frame synchronization signal output from the projection image generation unit 36, the sequence control unit 39 issues a shooting request to the camera input unit 30 and the camera 15 shoots.

The video image captured by the camera 15 is stored in a buffer (not shown) of the camera input unit 30. When the camera 15 finishes shooting, the camera 15 outputs a shooting completion signal. Upon receiving the shooting completion signal from the camera 15, the sequence control unit 39 issues a video storage command to the camera video analysis unit 33.

Upon receiving the video storage command, the camera video analysis unit 33 receives the captured video from the buffer of the camera input unit 30 and stores the video in the internal buffer of the camera video analysis unit 33.

This internal buffer can store N images, and the latest N frames of captured images are stored. Here, the value of N is defined in advance and is, for example, about N=30.

The camera image analysis unit 33 performs a superimposing process on N images. The superimposing method is, for example, comparative light composition. In this comparative bright combination, the pixel having the maximum value is selected from N images for each pixel position and combined.

Next, N frames of the projector image are superimposed (step S302). In the process of step S302, the sequence control unit 39 issues a video storage command to the projection video analysis unit 37.

Upon receiving the video storage command, the projection video analysis unit 37 receives the projection image from the projection video generation unit 36 and stores the received video in the internal buffer of the projection video analysis unit 37. This internal buffer can store N images, and the latest N frames of projected images are stored.

The value of N is specified in advance, and for example, N=30. The projected image analysis unit 37 performs a superposition process of N images. The superimposing method is the comparative bright combination, as in the process of step S301.

Then, the projected image analysis unit 37 analyzes the generated superimposed image to determine whether or not the image can detect the four corners of the image (step S303). When it is determined that the video is a video in which the corner portion can be detected, the projected video analysis unit 37 analyzes the superimposed video and calculates the coordinates of the four corners of the video (step S304).

Also, in the processing of step S303, when it is determined that the video is not a corner-detectable image, the processing returns to step S301.

Next, the projected image analysis unit 37 compares the calculated coordinates of the four corners of the image with the past calculation results, and determines whether or not the coordinate deviation exceeds a predetermined threshold value ( Step S305).

If it is determined that the coordinate shift does not exceed the threshold value, the projected image analysis unit 37 determines that no temporal shift has occurred, and the process returns to step S301. If it is determined that the coordinate shift exceeds the threshold value, the projected image analysis unit 37 determines that a temporal shift has occurred, and detects the temporal shift (step S306). When the time-dependent shift is detected, the time-dependent shift correction, which is the process of step S105 of FIG. 5, is performed.

Further, in the process of step S305, the projection video analysis unit 37 stores the calculated latest coordinates of the four corners in a memory or the like (not shown) included in the projection video analysis unit 37 in order to compare the coordinates after the next time.

Due to the above, the process for detecting the time shift is completed.

FIG. 10 is an explanatory diagram showing an example of the temporal shift detection of FIG.

FIG. 10A shows a case where two images projected from two projectors have no time lag, and FIG. 10B shows two images projected from two projectors. It shows the case where there is a time lag in.

First, when there is no time lag between the two images projected from the two projectors, the projected images from the two projectors are displayed in an overlapping manner.

Therefore, as shown in FIG. 10A, the rectangular area where the projected images from the two projectors are displayed, in other words, the points at the four corners of the image display area are the points obtained by the initial adjustment in FIG. It corresponds to Am, Bm, Cm, Dm.

On the other hand, when the projected images from the two projectors deviate over time, the image display areas of the respective projectors deviate, so that the four corner points of each image display area are as shown in FIG. In addition, the points Am, Bm, Cm, and Dm obtained by the initial adjustment in FIG. 6 do not match.

Therefore, the coordinates of the corner point of the rectangular area projected from the two projectors are compared with the coordinates of the corner section obtained in the initial adjustment, and if the coordinates match, there is a time lag. You can determine that you have not. Further, when the coordinates do not match, it can be determined that a time lapse has occurred.

<About aging correction>
Next, a description will be given of the correction of time deviation when the time deviation is detected.

First, find the coordinates of the four corners when all projectors are fully lit. When the coordinates of all the projectors are obtained, the geometric correction parameters are calculated as in the initial adjustment shown in FIG.

Since this time lag correction is performed while the video content is being projected, it is important to find the coordinates of the corners when all the projectors are fully lit, without giving the viewer a feeling of strangeness.

Next, a method of obtaining the coordinates of the corner portion when the projector is fully lit in the above-described time-dependent shift correction will be specifically described.

FIG. 11 is an explanatory diagram showing an example of the calculation of the coordinates of the corner portion in the correction of the time lapse by the projection type video display system 10 of FIG.

Note that FIG. 11 shows an example of calculation of coordinates by the two

projectors

11 and 12 for the sake of simplicity.

The coordinate calculation method shown in FIG. 11 is to turn on the target projector that is the target of coordinate calculation and turn off the other projectors, that is, the non-target projectors.

Obtain the coordinates of the four corners of the projector 11 respectively. In this case, as shown on the left side of FIG. 11A, first, image projection is performed by the projector 11 that is the target of coordinate calculation. At this time, as shown on the right side of FIG. 11A, the non-target projector 12 is turned off. In this state, the coordinates of the four corners of the projector 11 are obtained.

Next, find the coordinates of the four corners of the projector 12. In this case, the projector 11 is turned off as shown on the left side of FIG. 11B, and the projector 12 is turned on as shown on the right side of FIG. 11B. In this state, the coordinates of the four corners of the projector 12 are obtained.

In the case of four projectors, the coordinates of the corners of the four projectors are obtained by sequentially turning on the target projectors and turning off all other non-target projectors.

With this, it is possible to correct the time lag while projecting the video content without giving the viewer a feeling of strangeness.

Here, the non-target projector was turned off, but the brightness may be reduced so that the image does not affect the calculation of the coordinates, instead of turning off the non-target projector.

FIG. 12 is a flow chart showing an example of processing in time deviation correction using the coordinate calculation example of FIG. 11.

First, the sequence control unit 39 sets the target projector number, which is a variable held in the projected image selection unit 31, to 0 (step S401). Then, the projector that is not the target is turned off (step S402).

In the process of step S402, the sequence control unit 39 issues a command to turn off the image to the control circuit 29 of the projector (eg, projectors 12 to 14) that is not the target via the communication control unit 35 according to the target projector number. ..

The control circuit 29 receiving the command from the sequence control unit 39 controls the optical system 27 to turn off the light. As a result, the projectors 12 to 14, which are not the targets, are turned off, and only the image of the target projector (for example, the projector 11) is projected on the screen 50.

After that, the processes of steps S403 to S408 of FIG. 12 are the same as the processes of steps S204 to S209 of FIG. Then, using the geometrical correction parameters calculated in this way, the temporal shift is corrected as shown in FIG.

Due to the above, it is possible to automatically correct the time lag periodically, so that it is not necessary for the user to readjust after installing the projectors 11 to 14. Thereby, convenience can be improved.

Also, since the time lag is automatically corrected during the projection of the moving image content, it is possible to reduce the continuous projection of the moving image content with the shifted image. As a result, the viewer can be provided with high-quality video.

(Embodiment 2)
<Coordinate calculation example>
FIG. 13 is an explanatory diagram showing an example of the calculation of the coordinates of the corner portion in the correction of the time-dependent shift according to the second embodiment.

Note that FIG. 13 also shows an example of calculating coordinates by the two

projectors

11 and 12 for the sake of simplicity. The configuration of the projection-type image display system 10 is the same as that of the projection-type image display system 10 in FIG.

The coordinate calculation method shown in FIG. 13 is to turn on the projector that is the target of coordinate calculation and reduce the brightness of the corner portion of the projected image in the other projectors that are not the target.

First, as shown on the left side of FIG. 13A, the projector 11 that is the target of coordinate calculation is turned on, and as shown on the right side of FIG. Reduces the brightness of the corners. In this state, the coordinates of the four corners in the projected image of the projector 11 are obtained.

When the coordinates of the four corners of the projector 11 are obtained, as shown on the right side of FIG. 13B, the lowered brightness of the corners of the projector 12 is returned to the standard, and the left side of FIG. As shown in, the brightness of the corner portion of the projected image on the projector 11 is reduced. In this state, the coordinates of the four corners of the projector 12 are obtained.

With this, when calculating the coordinates, the brightness of only the corner part decreases and the brightness of the other areas does not decrease, so it is possible to calculate the coordinates of the corner part while reducing the discomfort of the projected image.

Here, the brightness of the corner portion projected by the non-target projector is reduced, but the projector may be controlled so that the corner portion of the projected image is gradation. Further, the corner portion that reduces the brightness may have a shape that allows the corner portion to be easily detected.

FIG. 14 is a flow chart showing an example of processing in time deviation correction using the coordinate calculation example of FIG. 13.

First, the sequence control unit 39 sets the target projector number, which is a variable held in the projected image selection unit 31, to 0 (step S501). Subsequently, the brightness of the corner portion projected by the non-target projector is reduced (step S502).

In the process of step S502, the sequence control unit 39 causes the control circuit 29 of the projector (for example, the projectors 12 to 14) that is not the target to control the brightness of the corner portion of the projected image via the communication control unit 35 according to the target projector number. Issue a command that lowers the

The control circuit 29 that receives the command from the sequence control unit 39 controls the mask generation circuit 22 to generate a mask that reduces the brightness of the corner portion of the projected image. The image calculation circuit 24 synthesizes the mask generated by the mask generation circuit 22 into a projected image and projects it by the optical system 27.

As a result, the luminance of the corner portion of the projected image of the projectors 12 to 14, which is not the target, is reduced. Therefore, the coordinates of the corner portion of the projected image of the target projector (for example, the projector 11) whose luminance is not reduced can be calculated accurately. You can

After that, the processes of steps S503 to S508 of FIG. 14 are the same as the processes of steps S204 to S209 of FIG. Then, using the geometrical correction parameters calculated in this way, the temporal shift is corrected as shown in FIG.

Due to the above, it is possible to correct the time lag while further reducing the discomfort of the projected image.

(Embodiment 3)
<Coordinate calculation example>
FIG. 15 is an explanatory diagram showing an example of the coordinate calculation of the corner portion according to the third embodiment.

FIG. 15 shows an example of displaying a marker on the corner section by the projector to be detected in the coordinate calculation method shown in FIG. The configuration of the projection type video display system 10 is the same as that of the projection type video display system 10 of FIG.

In this case, as shown on the left side of FIG. 15A, the projector 11 which is the target of coordinate calculation is turned on, and the markers 11 are displayed on the four corners of the projected image by the projector 11 in a superimposed manner.

Further, in the non-target projector 12, as shown on the right side of FIG. 15A, the brightness of the corner portion of the projected image is reduced. In this state, the coordinates of the four corners in the projected image of the projector 11 are obtained. By displaying the marker 60, the coordinates of the four corners of the projector 11 can be detected more accurately and in a shorter time.

When the coordinates of the four corners of the projector 11 are obtained, the brightness of the corners of the projected image is reduced as shown on the left side of FIG. 15(b). Further, the projector 12 restores the brightness of the corners to the normal level and displays the markers 61 on the respective corners, as shown on the right side of FIG. As a result, the coordinates of the four corners of the projector 12 can be detected more accurately and in a shorter time.

The

markers

60 and 61 are generated by the marker generation circuit 21. The video calculation circuit 24 combines the marker generated by the marker generation circuit 21 with the projected video content. The video content combined with the

markers

60 and 61 is projected by the optical system 27.

The

markers

60 and 61 are not limited as long as they have a shape such that a corner portion such as a quadrangle or a circle can be accurately detected.

Alternatively, the

markers

60 and 61 may have colors close to the hue of the displayed video content. For example, when the image near the

markers

60 and 61 is a grassland or the like, the display color of the

markers

60 and 61 is green, which is close to the color of the grassland, and when the image is a blue sky, the

markers

60 and 61 are close to the blue sky. Display in blue, etc. Thereby, the

markers

60 and 61 can be made inconspicuous, and the viewer's discomfort can be reduced.

<Other examples of coordinate calculation>
FIG. 16 is an explanatory diagram showing another example of FIG.

In FIG. 16, an example is shown in which the

markers

60 and 61 are not superimposed and displayed on the corner portion, but a white frame is superimposed and displayed on the outer peripheral portion of the display area of the image projected by the projector. It should be noted that the black line on the outer peripheral portion of FIG. 16 is for making the drawing easier to see and does not actually exist.

First, as shown in FIG. 16A, a frame-shaped frame 60a is superimposed and displayed on the outer peripheral portion of the projected image of the projector 11, and the coordinates of the four corner portions are obtained. After that, as shown in FIG. 16B, a frame-shaped frame 61a is superimposed and displayed on the outer peripheral portion in the projected image of the projector 12, and the coordinates of the four corner portions are respectively obtained.

Also by this, the coordinates of the four corners of the

projectors

11 and 12 can be detected more accurately and in a shorter time.

Due to the above, it is possible to correct the time lag more accurately and in a shorter time while reducing the viewer's discomfort while watching the video content.

(Embodiment 4)
<Coordinate calculation example>
FIG. 17 is an explanatory diagram showing an example of the calculation of the coordinates of the corner portion in the correction of the time lapse according to the fourth embodiment. The configuration of the projection type video display system 10 is the same as that of the projection type video display system 10 of FIG.

Note that FIG. 17 also shows an example of calculating coordinates by the two

projectors

11 and 12 for the sake of simplicity.

The coordinate calculation method shown in FIG. 17 includes a process of increasing the brightness of the corner part of the target projector whose brightness has decreased, in addition to the process of FIG. 13 of decreasing the brightness of the corner part of the projected image on the non-target projector. It is something to do.

First, as shown on the left side of FIG. 17A, the projector 11 that is the target of coordinate calculation is turned on, and as shown on the right side of FIG. Reduces the brightness of the corners.

At this time, the projector 11 increases the brightness of the corner portion of the projected image of the projector 12 whose brightness has decreased. At this time, the projector 11 increases the brightness to such an extent that the corner portion can be clearly detected.

By doing this, it is possible to compensate for the decrease in brightness at the corners, so it is possible to provide viewers with a projected image with less discomfort. In this state, the coordinates of the four corners in the projected image of the projector 11 are obtained.

When the coordinates of the four corners of the projector 11 are obtained, as shown on the left side of FIG. 17(b), the brightness of the corners of the projected image on the projector 11 is reduced, and at the right side of FIG. 17(b). As described above, the lowered brightness of the corner portion of the projector 12 is increased to be brighter than the specified value. Also in this case, the projector 12 increases the brightness to such an extent that the corner portion can be clearly detected.

In this state, the coordinates of the four corners of the projector 12 are obtained respectively. This also makes it possible to compensate for the decrease in the brightness of the corner portion, and thus it is possible to provide the viewer with a projected image with less discomfort.

In this case, in order to increase the brightness of the corner portion shown in FIG. 17, the sequence control unit 39 controls the mask generation circuit 22 to generate a mask for decreasing the brightness of the corner portion of the projected image and a mask for increasing the brightness of the corner portion. Let

With this, the temporal shift is corrected as shown in FIG. 8 described above, using the geometric correction parameters calculated from the coordinates of the corners of the projected image of each projector obtained.

Depending on the content of the projected image, the peripheral part of the image may be displayed brightly. In the case where such content is displayed, when the brightness of the corner portion is increased as shown in FIG. 17, the overflow exceeds the upper limit of the brightness value of the pixel, and the displayed image is saturated. There is.

Therefore, when the surroundings of the projected content video are bright, the projection video analysis unit 37 determines whether or not the brightness value of the pixel overflows if the brightness of the corner unit is increased during the coordinate calculation. This process is performed for each frame.

When it is determined that an overflow occurs, the projected image analysis unit 37 outputs a control signal to the sequence control unit 39 to stop the increase in the brightness of the corner portion in the coordinate calculation process. When the sequence control unit 39 receives the control signal, the sequence control unit 39 stops increasing the brightness of the corner portion by the frame and cancels the coordinate calculation process.

When the sequence control unit 39 receives a control signal from the projection video analysis unit 37 indicating that the video content has no overflow, the sequence control unit 39 restarts the increase in the brightness of the corner unit and executes the coordinate calculation process.

With the above, it is possible to provide viewers with more comfortable moving image content in correction of time lapse.

(Embodiment 5)
<Example of correction of time lag>
As shown in FIG. 9, in the temporal shift detection process, camera images are superimposed to detect the shift. Therefore, for example, when the installed projector is displaced in the forward direction, the projected image of the displaced projector is only reduced, and the displacement cannot be detected.

Therefore, in the fifth embodiment, a technique capable of correcting the temporal shift even when the projector shifts in the forward direction will be described.

FIG. 18 is a flowchart showing an example of the outline of the overall processing in the projection type video display system 10 according to the fifth embodiment. FIG. 19 is an explanatory diagram showing an example of image content in which a time lag has occurred.

The video content shown in FIG. 19(a) shows a case where no lag has occurred, and the video content shown in FIG. 19(b) shows that the projector 11 out of the two

projectors

11 and 12 moves forward. An example of a case in which there is a time lag that deviates in time is shown.

When the projector 11 shown in FIG. 19(b) is displaced in the forward direction and is displaced with time, the image display area of the projector 11 displaced forward is only small as described above. Therefore, in the case of the processing for detecting the time-dependent shift shown in FIG. 9, since the four corners are detected from the camera image captured by superimposing N frames, the time-dependent shift cannot be detected.

Therefore, as shown in the flowchart of FIG. 18, the process of step S606 is added to the initial adjustment process to reduce the occurrence of time lag due to the forward displacement of the projector.

Here, the processing of steps S601 to S605 in the flowchart of FIG. 18 is the same as the processing of steps S101 to S105 of FIG. 5, so description thereof will be omitted.

In the process of step S606, if it is not detected in the detection process of step S604 that a time-dependent shift has occurred, the sequence control unit 39 of FIG. 2 determines whether or not a preset time has elapsed. .. The set time is, for example, about 24 hours.

When the set time has elapsed, the sequence control unit 39 executes the initial adjustment which is the process of step S601, calculates the geometric correction parameter, and corrects the deviation of the projected image. This initial adjustment is the process shown in FIG.

With this, even if the projector is shifted forward over time, it can be corrected, so that good video content can be provided.

(Embodiment 6)
<Configuration example of projection type video display system>
FIG. 20 is an explanatory diagram showing an example of the configuration of the projection-type image display system 10 according to the sixth embodiment.

The projection-type image display system 10 shown in FIG. 20 includes projectors 11 to 14, a camera 15, and a personal computer 16, as in FIG.

In the projection-type image display system 10 of FIG. 2, the initial adjustment process and the temporal deviation correction process are executed by the projectors 11 to 14. However, in the projection-type image display system 10 shown in FIG. An example is shown in which the personal computer 16 is provided with a function of executing the process of the deviation correction.

The projectors 11 to 14 each include a video interface 20, an optical system 27, a communication interface 28, and a control circuit 29. The operations of the video interface 20, the optical system 27, the communication interface 28, and the control circuit 29 are the same as those in FIG.

The personal computer 16 includes a camera input unit 30, a projection video selection unit 31, a video transmission unit 32, a camera video analysis unit 33, a parameter calculation unit 34, a communication control unit 35, a projection video generation unit 36, a projection video analysis unit 37, and a storage. The personal computer 16 of FIG. 2 including the unit 38 and the sequence control unit 39 has the same configuration as the marker superimposing unit 41, the mask generation processing unit 42, which is a functional block that executes the initial adjustment process and the temporal deviation correction process. A pattern generation processing unit 43, a video calculation processing unit 44, a geometric correction processing unit 45, and a geometric correction parameter storage unit 46 are newly provided.

Regarding the operations of the marker superimposing unit 41, the mask generation processing unit 42, the pattern generation processing unit 43, the image calculation processing unit 44, the geometric correction processing unit 45, and the geometric correction parameter storage unit 46 which are newly provided in the personal computer 16, The description is omitted because it is the same as the marker generation circuit 21, the mask generation circuit 22, the pattern generation circuit 23, the video calculation circuit 24, the geometric correction circuit 25, and the geometric correction parameter storage unit 26 of FIG. 2.

Further, the camera input unit 30, the projected image selection unit 31, the image transmission unit 32, the camera image analysis unit 33, the parameter calculation unit 34, the communication control unit 35, the projected image generation unit 36, the projected image analysis unit 37, the storage unit 38, Also, the operation of the sequence control unit 39 is the same as that of FIG.

As described above, by providing the personal computer 16 with the functional blocks that execute the initial adjustment process and the time lag correction process, the projectors 11 to 14 can be downsized and the cost can be reduced.

(Embodiment 7)
<Configuration example of projection type video display system>
In the seventh embodiment, a configuration that does not require the personal computer 16 and the camera 15 of FIG. 2 will be described.

FIG. 21 is an explanatory diagram showing an example of the configuration of the projection type video display system 10 according to the seventh embodiment.

The projection-type image display system 10 shown in FIG. 21 includes projectors 11 to 14 and a mobile terminal 90, and the mobile terminal 90 executes the functions of the camera 15 and the personal computer 16.

Regarding the configuration of the projectors 11 to 14, a communication interface 28a is provided instead of the communication interface 28 of FIG. Other connection configurations of the video interface 20, the marker generation circuit 21, the mask generation circuit 22, the pattern generation circuit 23, the video calculation circuit 24, the geometric correction circuit 25, the geometric correction parameter storage unit 26, the optical system 27, and the control circuit 29. Is the same as that in FIG. 2, and the description thereof is omitted.

The communication interface 28a performs wireless communication such as wireless LAN (Local Area Network) and Bluetooth (registered trademark). A personal computer (not shown) is connected to the video interface 20. The personal computer outputs video content data that is a projected video to be displayed to the viewer.

The mobile terminal 90 is an electronic mobile device such as a smartphone or a tablet. The mobile terminal 90 includes a camera 80, a camera input unit 81, a camera image analysis unit 82, a parameter calculation unit 83, a storage unit 84, a sequence control unit 85, a display unit 86, and a communication control unit 87.

The camera input unit 81, camera image analysis unit 82, parameter calculation unit 83, storage unit 84, sequence control unit 85, display unit 86, and communication control unit 87 are interconnected by an internal bus 88.

The communication control unit 87 performs, for example, wireless communication according to a communication standard such as 3G (Generation) and 4G and wireless communication such as a wireless LAN (Local Area Network) and Bluetooth (registered trademark). The display unit 86 is, for example, a liquid crystal display, and displays various kinds of information.

Here, the video content data may be transmitted from the mobile terminal 90 instead of the personal computer described above. In that case, the communication control unit 87 transmits to the wireless communication interface 46 of the projectors 11 to 14 by wireless communication.

Regarding the camera 80, the camera input unit 81, the camera image analysis unit 82, the parameter calculation unit 83, the storage unit 84, the sequence control unit 85, the display unit 86, and the communication control unit 87, the camera 15, the camera input unit 30 of FIG. The camera image analysis unit 33, the parameter calculation unit 34, the storage unit 38, and the sequence control unit 39 are the same as those described above, and thus description thereof will be omitted.

By thus configuring the projection-type image display system 10 from the projectors 11 to 14 and the mobile terminal 90, the system can be downsized.

(Embodiment 8)
<Configuration example of projection type video display system>
FIG. 22 is an explanatory diagram showing an example of the configuration of the projection type video display system 10 according to the eighth embodiment.

The projection type video display system 10 shown in FIG. 22 includes projectors 11 to 14 and a personal computer 16.

22 is different from the projection type video display system 10 of FIG. 2 in that the projector 11 has a camera 95 built therein. Other configurations and operations are the same as those in FIG. 2, and therefore description thereof will be omitted.

In this way, by incorporating the camera 95 in the projector 11, it is possible to eliminate the work of installing the camera and the like, so that the convenience can be further improved. Also, the installation time in the projection type video display system 10 can be shortened.

Although the invention made by the inventor has been specifically described based on the embodiment, the invention is not limited to the embodiment, and various modifications can be made without departing from the scope of the invention. Needless to say.

10 Projection-type video display system 11 Projector 12 Projector 13 Projector 14 Projector 15 Camera 16 Personal computer 20 Video interface 21 Marker generation circuit 22 Mask generation circuit 23 Pattern generation circuit 24 Video operation circuit 25 Geometric correction circuit 26 Geometric correction parameter storage unit 27 Optical System 28 Communication interface 29 Control circuit 30 Camera input unit 31 Projected image selection unit 32 Image transmission unit 33 Camera image analysis unit 34 Parameter calculation unit 35 Communication control unit 36 Projected image generation unit 37 Projected image analysis unit 38 Storage unit 39 Sequence control unit 41 marker superimposing unit 42 mask generation processing unit 43 pattern generation processing unit 44 image calculation processing unit 45 geometric correction processing unit 46 geometric correction parameter storage unit 80 camera 81 camera input unit 82 camera image analysis unit 83 parameter calculation unit 84 storage unit 85 sequence Control unit 86 Display unit 87 Communication control unit 88 Internal bus 90 Mobile terminal 95 Camera

Claims

A projection type image display system for displaying a plurality of images in an overlapping manner,
A plurality of projectors for projecting the image,
A computer for outputting video data to the plurality of projectors;
An image capturing unit that captures the image projected by the plurality of projectors on the image projection surface;
Equipped with
A plurality of said projectors,
A geometric correction unit that corrects the geometric distortion of the projected image based on a geometric parameter;
An image projection unit that projects the image on the image projection surface,
Have
The computer is
An image analysis unit that analyzes the image captured by the image capturing unit and determines whether or not there is a time-dependent shift that causes a shift in the images projected by the plurality of projectors,
A control unit for controlling the plurality of projectors;
Have
The image analysis unit calculates coordinates of four corners of an image obtained by superimposing all of the images projected by each of the projectors captured by the image capturing unit, and the calculated coordinates and preset thresholds. By comparing with the value, it is determined that a time lapse has occurred when the coordinates exceed the threshold value,
The projection-type image display system, wherein the geometric correction unit corrects the image projected by each of the projectors when the image analysis unit determines that a time lag has occurred.
The projection type video display system according to claim 1,
The projection type image display system, wherein the control unit reduces the brightness of a part of the projection image of the projector that is not the target of coordinate calculation when the image capturing unit captures the image of each of the projectors.
The projection type video display system according to claim 1,
A projection-type image display system, wherein the control unit projects only an image of a projector which is a target of coordinate calculation and turns off an untargeted projector when the image capturing unit captures the image of each of the projectors.
The projection type video display system according to claim 1,
A plurality of said projectors,
A marker generation unit that generates a marker for assisting the calculation of the coordinates of the corner portion of the image,
An image calculation unit that superimposes the markers generated by the marker generation unit on four corners of the image,
Have
The image capturing unit captures the image on which the marker is superimposed and displayed for each of the projectors,
The projection type video display system, wherein the video analysis unit calculates coordinates of the corner unit from the video on which the marker captured by the imaging unit is displayed in a superimposed manner.
The projection type video display system according to claim 4,
The projection type image display system, wherein the marker generation unit generates a marker having a color similar to the projected image.
The projection type video display system according to claim 1,
A plurality of said projectors,
A marker generation unit that generates a marker for assisting the calculation of the corner portion of the image,
An image calculation unit that superimposes the markers generated by the marker generation unit on four corners of the image,
Have
The marker generated by the marker generation unit is a frame-shaped frame that surrounds the outer peripheral portion of the image,
The image capturing unit captures the image on which the marker is superimposed and displayed for each of the projectors,
The projection type video display system, wherein the video analysis unit calculates coordinates of the corner unit from the video on which the marker captured by the imaging unit is displayed in a superimposed manner.
The projection type video display system according to claim 1,
A plurality of said projectors,
A mask generation unit that generates a mask that increases or decreases the brightness of the image;
An image calculation unit that superimposes the mask generated by the mask generation unit on four corners of a projected image;
Have
The image capturing unit captures the image in which the brightness of the corner portion is increased or decreased by the mask for each of the projectors,
The projection type video display system, wherein the video analysis unit calculates coordinates of the corner from the video captured by the imaging unit.
A projection type image display system for displaying a plurality of images in an overlapping manner,
A plurality of projectors for projecting the image,
A computer for outputting video data to the plurality of projectors;
An image capturing unit that captures the image projected by the plurality of projectors on the image projection surface;
Equipped with
A plurality of said projectors,
A geometric correction unit that corrects the geometric distortion of the projected image based on a geometric parameter;
An image projection unit that projects the image on the image projection surface,
An image analysis unit that analyzes the image captured by the image capturing unit and determines whether there is a time-dependent shift that causes a shift in the images projected by the plurality of projectors,
Have
The image analysis unit calculates coordinates of four corners of the image projected by each of the projectors captured by the imaging unit, and compares the calculated coordinates with a preset threshold value. Then, it is determined that a time lapse has occurred when the coordinates exceed the threshold value,
The projection type image display system, wherein the geometric correction unit corrects the image projected by each of the projectors when the image analysis unit determines that a time lag has occurred.
A projection type image display system for displaying a plurality of images in an overlapping manner,
A plurality of projectors for projecting the image,
A computer for outputting video data to the plurality of projectors;
Equipped with
Among the plurality of projectors, one of the projectors has an imaging unit that captures the image projected on the image projection surface,
A plurality of said projectors,
A geometric correction unit that corrects the geometric distortion of the projected image based on a geometric parameter;
An image projection unit that projects the image on the image projection surface,
Have
The computer has an image analysis unit that analyzes the image captured by the imaging unit and determines whether or not there is a time-dependent shift that causes a shift in the images projected by the plurality of projectors.
The image analysis unit calculates coordinates of four corners of the image projected by each of the projectors captured by the imaging unit, and compares the calculated coordinates with a preset threshold value. Then, it is determined that a time lapse has occurred when the coordinates exceed the threshold value,
The projection type image display system, wherein the geometric correction unit corrects the image projected by each of the projectors when the image analysis unit determines that a time lag has occurred.
A projection type image display system for displaying a plurality of images in an overlapping manner,
A plurality of projectors for projecting the image,
A mobile terminal that detects and corrects a time-dependent shift that causes a shift in images projected by the plurality of projectors,
Equipped with
A plurality of said projectors,
A geometric correction unit that corrects the geometric distortion of the projected image based on a geometric parameter;
An image projection unit that projects the image on an image projection surface,
Have
The mobile terminal is
An imaging unit that captures the image projected by the plurality of projectors onto the image projection surface;
An image analysis unit that analyzes the image captured by the image capturing unit and determines whether or not the time lag has occurred in the images projected by the plurality of projectors,
Have
The video analysis unit calculates coordinates of four corners of the video projected by each of the projectors captured by the imaging unit, and compares the calculated coordinates with a preset threshold value. Then, it is determined that a time lapse has occurred when the coordinates exceed the threshold value,
The projection-type image display system, wherein the geometric correction unit corrects the image projected by each of the projectors when the image analysis unit determines that a time lag has occurred.