Patent Publication Number: US-2022217313-A1

Title: Control device, control method, control program, and projection system

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This is a continuation of International Application No. PCT/JP2020/032786 filed on Aug. 28, 2020, and claims priority from Japanese Patent Application No. 2019-177951 filed on Sep. 27, 2019, the entire disclosures of which are incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a control device, a control method, a computer readable medium storing a control program, and a projection system. 
     2. Description of the Related Art 
     In the related art, a projection system that displays one image on a large screen by dividing one image to generate a plurality of division images, and projecting the division images by a plurality of projection devices has been known (for example, see JP2005-286772A and JP2014-194464A). In addition, the technology of, in a case in which a failure of a part of projection devices occurs in a projection system that displays an image on a large screen by using a plurality of projection devices, projecting a reduced image onto a projectable region of the remaining projection devices (for example, see JP2018-4809A and JP2017-3910A). 
     SUMMARY OF THE INVENTION 
     One embodiment according to the technology of the present disclosure provides a control device for projection, a control method, a computer readable medium storing a control program, and a projection system that can efficiently perform information display using a projectable region even in a state in which a part of projection devices cannot perform projection. 
     An aspect of the present invention relates to a control device that controls projection by a plurality of projection units having different projection ranges, the device comprising a control unit that projects, by the plurality of projection units, a first image in which at least one content image is disposed on a first projection range having the projection ranges of the plurality of projection units, and an acquisition unit that acquires first attribute information which is associated with the content image and indicates whether an aspect ratio is made to be changeable or is maintained in a case in which a size of the content image is adjusted, in which the control unit projects a second image in which at least a part of the content image is disposed on a second projection range having a projection range of a projection unit except a part of projection units among the plurality of projection units, and adjusts the size of the content image in generation of the second image based on the first attribute information in a state in which projection is performed by the projection unit excluding the part of projection units among the plurality of projection units. 
     Another aspect of the present invention relates to a control method of controlling projection by a plurality of projection units having different projection ranges, the method comprising a control step of projecting, by the plurality of projection units, a first image in which at least one content image is disposed on a first projection range having the projection ranges of the plurality of projection units, and an acquisition step of acquiring first attribute information which is associated with the content image and indicates whether an aspect ratio is made to be changeable or is maintained in a case in which a size of the content image is adjusted, in which in the control step, a second image in which at least a part of the content image is disposed is projected on a second projection range having a projection range of a projection unit excluding a part of projection units among the plurality of projection units, and the size of the content image is adjusted in generation of the second image based on the first attribute information in a state in which projection is performed by the projection unit except the part of projection units among the plurality of projection units. 
     Still another aspect of the present invention relates to a control program causing a computer to function as the acquisition unit and the control unit of the control device according to the aspect described above. 
     Still another aspect of the present invention relates to a projection system comprising the control device according to the aspect described above, and the plurality of projection units. 
     According to the present invention, it is possible to provide a control device for projection, a control method, a control program, and a projection system that can efficiently perform information display using a projectable region even in a state in which a part of projection devices cannot perform projection. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic diagram showing a schematic configuration of a projection system  100 , which is an embodiment of a projection system of the present invention. 
         FIG. 2  is a schematic diagram showing a state in which projection is performed only by a second projection device  2 . 
         FIG. 3  is a schematic diagram showing an internal configuration of a first projection device  1  shown in  FIG. 1 . 
         FIG. 4  is a schematic diagram showing an example of projection of a first image  51  by the first projection device  1  and the second projection device  2 . 
         FIG. 5  is a schematic diagram showing an example of projection of a second image  52  only by the second projection device  2 . 
         FIG. 6  is a schematic diagram showing another example of the projection of the second image  52  only by the second projection device  2 . 
         FIG. 7  is a diagram showing an example of a functional block of a control device  4 . 
         FIG. 8  is a diagram showing an example of attribute information of a content acquired by an acquisition unit  41  shown in  FIG. 7 . 
         FIG. 9  is a flowchart showing an example of attribute information setting processing by the control device  4 . 
         FIG. 10  is a flowchart showing an example of attribute setting processing of image data shown in  FIG. 9 . 
         FIG. 11  is a flowchart showing an example of attribute setting processing of character data shown in  FIG. 9 . 
         FIG. 12  is a flowchart showing an example of attribute setting processing of an operating part shown in  FIG. 9 . 
         FIG. 13  is a flowchart showing an example of projection control processing of the second image  52  by the control device  4 . 
         FIG. 14  is a schematic diagram showing a modification example of the projection system  100 . 
         FIG. 15  is a schematic diagram showing a state in which projection is performed only by the first projection device  1 , the second projection device  2 , and a fourth projection device  9  shown in  FIG. 14 . 
         FIG. 16  is a schematic diagram showing an example of the projection of the first image  51  by each projection device shown in  FIG. 14 . 
         FIG. 17  is a schematic diagram showing an example of the projection of the second image  52  only by the first projection device  1 , the second projection device  2 , and the fourth projection device  9  shown in  FIG. 15 . 
         FIG. 18  is a schematic diagram showing another example of the projection of the second image  52  only by the first projection device  1 , the second projection device  2 , and the fourth projection device  9  shown in  FIG. 15 . 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 
       FIG. 1  is a schematic diagram showing a schematic configuration of a projection system  100 , which is the embodiment of a projection system of the present invention. The projection system  100  comprises a first projection device  1 , a second projection device  2 , a control device  4 , an imaging unit  5 , and a screen  6 . The first projection device  1  and the second projection device  2  are each configured by, for example, a liquid crystal projector, a projector using liquid crystal on silicon (LCOS), or the like. Hereinafter, it is assumed that each of the first projection device  1  and the second projection device  2  is the liquid crystal projector. 
     A first device projection range  11  is a projection range of the first projection device  1  on the screen  6 . A second device projection range  12  is a projection range of the second projection device  2  on the screen  6 , and is a range different from the first device projection range  11 . In the example shown in  FIG. 1 , the second device projection range  12  is a range with which only a part of the first device projection range  11  overlaps. 
     A first system projection range  31  is a projection range having the first device projection range  11  and the second device projection range  12 . For convenience of illustration, the first system projection range  31  is shown by a broken line frame slightly larger than an actual size. Specifically, the first system projection range  31  has a horizontally long rectangular shape including a portion of the first device projection range  11  that does not overlap with the second device projection range  12 , a portion in which the first device projection range  11  and the second device projection range  12  overlap with each other, and a portion of the second device projection range  12  that does not overlap with the first device projection range  11 . The first system projection range  31  constitutes a first projection range having projection ranges of a plurality of projection devices (first projection device  1  and second projection device  2 ) provided in the projection system  100 . 
     The projection system  100  displays a horizontally long projection target image in the first system projection range  31  by projecting a division image onto the first device projection range  11  by the first projection device  1 , projecting a division image onto the second device projection range  12  by the second projection device  2 , and joining these two division images. The projection target image, which is projected onto the first system projection range  31  by the first projection device  1  and the second projection device  2 , constitutes a first image. 
     The control device  4  is a device including a control unit including various processors, a communication interface (not shown) which communicates with each unit, and a storage medium  4   a  such as a hard disk, a solid state drive (SSD), or a read only memory (ROM), and controls the first projection device  1 , the second projection device  2 , and the imaging unit  5  in an integrated manner. 
     Examples of the various processors of the control unit of the control device  4  include a central processing unit (CPU), which is a general-purpose processor that executes a program and performs various processing, programmable logic device (PLD), which is a processor whose circuit configuration can be changed after manufacturing, such as field programmable gate array (FPGA), or a dedicated electric circuit, which is a processor having a circuit configuration specially designed for executing specific processing such as an application specific integrated circuit (ASIC), and the like. 
     The structure of these various processors is, more specifically, an electric circuit in which circuit elements such as semiconductor elements are combined. The control unit of the control device  4  may be configured by one of the various processors, or may be configured by a combination of two or more processors of the same type or different types (for example, a combination of a plurality of the FPGAs or a combination of the CPU and the FPGA). 
     The imaging unit  5  comprises an imaging element, such as a charged coupled device (CCD) type image sensor or a metal oxide semiconductor (MOS) type image sensor which images a subject through an imaging optical system, and images at least the first system projection range  31  on the screen  6 . The captured image captured by the imaging unit  5  is input to the control device  4 . 
     Although in the projection system  100 , the imaging unit  5  is provided independently, the imaging unit  5  may be built in the first projection device  1  or the second projection device  2 . In addition, in the projection system  100 , the imaging unit  5  may be omitted. 
       FIG. 2  is a schematic diagram showing a state in which projection is performed only by the second projection device  2 . For example, it is assumed that the first projection device  1  is in an unsteady state in which the projection onto the first device projection range  11  cannot be performed due to a failure of the first projection device  1  or the like. In this case, the control device  4  projects the image onto the second device projection range  12  by using only the second projection device  2  which can perform the projection among the first projection device  1  and the second projection device  2 . 
     A second system projection range  32  shown in  FIG. 2  is a projection range having only the second device projection range  12  of the second projection device  2 . For convenience of illustration, the second system projection range  32  is shown by a broken line frame slightly larger than an actual size. The second system projection range  32  constitutes a second projection range having a projection range of a projection unit (second projection device  2 ) excluding a part of projection units (first projection device  1 ) among the projection devices provided in the projection system  100 . 
     For example, in a case in which the control device  4  detects that the projection by the first projection device  1  is not possible, the control device  4  projects the projection target image onto the second system projection range  32  (second device projection range  12 ) of the screen  6  by the second projection device  2 . The projection target image, which is projected onto the second system projection range  32  only by the second projection device  2 , constitutes a second image. 
     Since the second system projection range  32  is narrower than the first system projection range  31 , it is necessary that a size of the second image projected onto the second system projection range  32  is smaller than a size of the first image projected onto the first system projection range  31 . Therefore, in a state in which the control device  4  is put into a state of performing projection only by the second projection device  2 , the control device  4  generates the second image having a size smaller than the first image, and projects the generated second image onto the second system projection range  32  by the second projection device  2 . The size is a size of the display (projection) on the screen  6 . 
     Examples of a cause of the unsteady state in which the first projection device  1  cannot perform the projection include various causes, such as a failure or deterioration of an internal component of the first projection device  1 , stop of the power supplied to the first projection device  1 , a shortage of a battery residual quantity of the first projection device  1 , a communication failure between the first projection device  1  and other devices (for example, control device  4 ), and turning-off of the power switch of the first projection device  1  by a user. 
     The detection by the control device  4  that the first projection device  1  cannot perform the projection can be performed, for example, based on various pieces of information, such as reception of an alarm signal output by the first projection device  1 , an unreceived response signal to a signal transmitted to the first projection device  1 , and an imaging result of the first device projection range  11  by the imaging unit  5 . 
       FIG. 3  is a schematic diagram showing an internal configuration of the first projection device  1  shown in  FIG. 1 . Note that an internal configuration of the second projection device  2  shown in  FIG. 1  is the same as that of the first projection device  1 , and thus the description thereof will be omitted. The first projection device  1  comprises a projection unit  23  and a control unit  24 . 
     The projection unit  23  comprises a display unit  21  including a light source  21   a  and an optical modulation unit  21   b,  and a projection optical system  22 . 
     The light source  21   a  includes a light emitting element such as a laser or a light emitting diode (LED), and emits white light, for example. 
     The optical modulation unit  21   b  includes three liquid crystal panels which modulate, based on image information, each color light emitted from the light source  21   a  and separated into three colors of red, blue, and green by a color separation mechanism (not shown) to emit each color image. These three liquid crystal panels may be equipped with red, blue, and green filters, respectively, and modulate the white light emitted from the light source  21   a  by each liquid crystal panel to emit each color image. 
     The projection optical system  22  receives light from the display unit  21 , and includes a relay optical system including at least one lens, for example. The light passing through the projection optical system  22  is projected onto the screen  6 . 
     The control unit  24  controls the projection unit  23  based on data for display input from the control device  4  to project an image based on the data for display on the screen  6 . The data for display input to the control unit  24  includes three of data for red display, data for blue display, and data for green display. 
       FIG. 4  is a schematic diagram showing an example of projection of the first image  51  by the first projection device  1  and the second projection device  2 , In a case in which both the first projection device  1  and the second projection device  2  can perform the projection, the control device  4  projects the first image  51  onto the first system projection range  31  (first projection range) by the first projection device  1  and the second projection device  2 , The first system projection range  31  is a range having the first device projection range  11  of the first projection device  1  and the second device projection range  12  of the second projection device  2 , as shown in  FIG. 1 . 
     The first image  51  is an image having the same shape and size as the first system projection range  31 , for example. As a result, the entire first image  51  can be projected in a large size by using the first system projection range  31  without waste. In the first image  51 , an image content IMG 1 , a text content TXT 1 , a text content TXT 2 , and an operating part CTR 1  are disposed as contents. 
     The image content IMG 1  is, for example, image data drawn based on image data, such as a bitmap image or a vector image. In the example shown in  FIG. 4 , the image content IMG 1  is a bitmap image obtained by imaging three people. 
     The text contents TXT 1  and TXT 2  are character data drawn based on a text file including a character code, such as plain text or rich text. In the example shown in  FIG. 4 , each of the text contents TXT 1  and TXT 2  is a character string describing a person appearing in the image content IMG 1 . The text content TXT 1  is a character string starting with “this person is”. The text content TXT 2  is a character string starting with “history”. 
     The operating part CTR 1  is an operating part that indicates a region for receiving an instruction from the user. In the example shown in  FIG. 4 , the operating part CTR 1  has a character “OK”, and is a button for giving an instruction for the transition to the next screen. 
     For example, it is assumed that the control device  4  displays information in a slide show format, and the first image  51  is one slide included in the slide show. In this case, in a case in which the user indicates the region of the operating part CTR 1  with a pointer or the like, the control device  4  projects the next slide of the first image  51  onto the first system projection range  31  instead of the first image  51 . 
     The drawing of the first image  51  will be described. For example, drawing data for projecting the first image  51  is stored in the storage medium  4   a  shown in  FIG. 1 . This drawing data includes the image content IMG 1 , the text content TXT 1 , the text content TXT 2 , and the operating part CTR 1 . In addition, this drawing data includes disposition information indicating the disposition (position or size) of these contents. 
     The control device  4  reads out the drawing data from the storage medium  4   a,  and generates the first image  51  in which each content included in the drawing data is disposed based on the disposition information included in the drawing data. Moreover, the control device  4  projects the generated first image  51  onto the first system projection range  31  by the first projection device  1  and the second projection device  2 . 
       FIG. 5  is a schematic diagram showing an example of projection of the second image  52  only by the second projection device  2 . For example, in a state in which the projection by the first projection device  1  onto the first device projection range  11  is not possible and the projection is performed only by the second projection device  2  due to the failure of the first projection device  1  or the like, the control device  4  projects the second image  52  onto the second system projection range  32  (second projection range) by the second projection device  2 . The second system projection range  32  is a range having only the second device projection range  12  of the second projection device  2 , as shown in  FIG. 2 . 
     The second image  52  is an image in which at least a part of the contents included in the first image  51  is disposed. In the example shown in  FIG. 5 , in the second image  52 , all of the contents included in the first image  51 , that is, the image content IMG 1 , the text contents TXT 1  and TXT 2 , and the operating part CTR 1  are disposed. However, in a case in which it is difficult to dispose all of these contents in the second image  52 , a part of these contents may not be disposed in the second image  52 . 
     The second system projection range  32  onto which the second image  52  is projected is narrower than the first system projection range  31  onto which the first image  51  is projected. Therefore, the control device  4  generates the second image  52  of which the size fits in the second system projection range  32 . 
     In this case, it is assumed that the first image  51  is reduced with a fixed aspect ratio in order to generate the second image  52  that fits in the second system projection range  32 . In this case, since the first image  51  having the same shape and size as the first system projection range  31  has a different aspect ratio with respect to the second system projection range  32 , the second image  52  is generated by reducing the first image  51  such that a length (horizontal width) of a long side of the first image  51  fits in the horizontal width of the second system projection range  32 . Therefore, the size of the second image  52  is reduced, the visibility of the second image  52  is decreased, and there is a region of the second system projection range  32  onto which the image is not projected. 
     In addition, in order to generate the second image  52  that fits in the second system projection range  32 , the first image  51  is reduced while changing the aspect ratio of the first image  51  to match the aspect ratio of the second system projection range  32 . In this case, there is no region of the second system projection range  32  onto which the second image  52  is not projected, but the aspect ratio is also changed for the content for which it is not desirable to change the aspect ratio, such as the image content IMG 1  included in the first image  51 . 
     On the other hand, the control device  4  according to the present embodiment generates the second image  52  in which at least a part of the contents included in the first image  51  is disposed again based on the drawing data for projecting the first image  51 . In this case, the control device  4  acquires, for each of the contents included in the first image  51 , first attribute information (for example, Keep_aspect, which will be described below) indicating whether the aspect ratio is made to be changeable in a case in which the size of the content is adjusted or the aspect ratio is maintained in a case in which the size of the content is adjusted. 
     Moreover, the control device  4  disposes each content on the second image  52  based on the acquired first attribute information in a case in which the second image  52  is generated. For example, the first attribute information of the image content IMG 1  indicates that the aspect ratio is maintained in a case in which the size of the image content IMG 1  is adjusted. In addition, the first attribute information each of the text contents TXT 1  and TXT 2 , and the operating part CTR 1  indicates that the aspect ratio is made to be changeable in a case in which the size of each content is adjusted. 
     In this case, for example, as shown in  FIG. 5 , the control device  4  generates the second image  52  in which the image content IMG 1  of which the size is adjusted while maintaining the aspect ratio, the text contents TXT 1  and TXT 2  of which the size is adjusted such that the aspect ratio is changeable, and the operating part CTR 1  are disposed. 
     As a result, the image content IMG 1  can be disposed in the second image  52  by adjusting the size of the image content IMG 1  for which it is not desirable to change the aspect ratio while maintaining the aspect ratio. In addition, for the text contents TXT 1  and TXT 2 , and the operating part CTR 1  which have little influence even in a case in which the aspect ratio is changed, these contents can be flexibly disposed in an empty region of the second system projection range  32  by adjusting the size such that the aspect ratio is changeable and disposing the second image  52 . 
       FIG. 6  is a schematic diagram showing another example of the projection of the second image  52  only by the second projection device  2 . For example, in a state in which the projection by the first projection device  1  onto the first device projection range  11  is not possible and the projection is performed only by the second projection device  2  due to the failure of the first projection device  1  or the like, the control device  4  may switch between a projection state  61  and a projection state  62  by the second projection device  2  at regular time intervals. 
     The projection state  61  is a state in which the second image  52  in which the image content IMG 1 , the text content TXT 1 , and the operating part CTR 1  are disposed is projected. That is, the text content TXT 2  is not included in the second image  52  in the projection state  61 . 
     The projection state  62  is a state in which the second image  52  in which the image content IMG 1 , the text content TXT 2 , and the operating part CTR 1  are disposed is projected. That is, the text content TXT 1  is not included in the second image  52  in the projection state  62 . 
     In addition, the projection region of the text content TXT 1  in the projection state  61  and the projection region of the text content TXT 2  in the projection state  62  overlap with each other. That is, the control device  4  alternately projects the text content TXT 1  and the text content TXT 2  onto a part of the region of the second image  52  while projecting the second image  52 . 
     For example, the control device  4  acquires, for each of the contents included in the first image  51 , second attribute information (for example, Always_disp, which will be described below) indicating whether the content is always projected in a state in which the projection by the partial projection device in the projection system  100  is not possible or the content is alternately projected with other contents in a state in which the projection by the partial projection device in the projection system  100  is not possible. 
     Moreover, the control device  4  disposes each content on the second image  52  based on the acquired second attribute information in a case in which the second image  52  is generated. For example, the second attribute information of each of the image content IMG 1  and the operating part CTR 1  indicates that the content is always displayed in a state in which the projection by the partial projection device in the projection system  100  is not possible. In addition, the second attribute information of each of the text contents TXT 1  and TXT 2  indicates that the content is alternately projected with other contents in a state in which the projection by the partial projection device in the projection system  100  is not possible. 
     In this case, for example, as shown in  FIG. 6 , the control device  4  generates the second image  52  in which the image content IMG 1  and the operating part CTR 1  are disposed not to overlap with other contents, and the text contents TXT 1  and TXT 2  are disposed at positions overlapping with each other. Moreover, in a case in which the second image  52  is projected, the control device  4  switches between the projection state  61  in which the text content TXT 1  is projected and the text content TXT 2  is not projected, and the projection state  62  in which the text content TXT 2  is projected and the text content TXT 1  is not projected, at regular time intervals. 
     As a result, the image content IMG 1  and the operating part CTR 1  can be always projected, and the text contents TXT 1  and TXT 2  can be temporally alternately projected with each other. Moreover, since the text contents TXT 1  and TXT 2  are disposed at positions overlapping with each other, it is possible to dispose and project each content in a larger size. 
       FIG. 7  is a diagram showing an example of a functional block of the control device  4 . As shown in  FIG. 7 , the control device  4  comprises an acquisition unit  41  and a control unit  42 . The acquisition unit  41  acquires the first attribute information and second attribute information described above for each content of the first image  51 . 
     Further, the acquisition unit  41  may acquire third attribute information or a data type indicating the priority for each content of the first image  51 . The priority of the content is information indicating a degree of preferentially displaying the content as compared with other contents. Preferentially displaying the content may mean that other contents are preferentially reduced over the content, a reduction width of the content may be smaller than those of the other contents, or both of these. 
     Each attribute information is stored, for example, in the storage medium  4   a  in association with each content, and the control device  4  acquires each attribute information from the storage medium  4   a.  Alternatively, each attribute information is stored in an external device of the control device  4  in association with each content, and the control device  4  may acquire each attribute information from the external device using a communication interface. 
     The acquisition of each attribute information by the acquisition unit  41  need only be performed before the generation of the second image  52  described above. For example, the acquisition unit  41  may acquire each attribute information in a case in which the first image  51  is projected onto the first system projection range  31  without any failure of the projection device or the like, or the acquisition unit  41  may acquire each attribute information after the failure of the projection device or the like occurs. 
     The control unit  42  controls the projection by each projection device included in the projection system  100 . Specifically, the control unit  42  comprises an image generation unit  42   a  and a projection control unit  42   b.  The image generation unit  42   a  performs generation of the first image  51  or the second image  52  described above. In addition, the image generation unit  42   a  uses each attribute information acquired by the acquisition unit  41  in the generation of the second image  52 . 
     The projection control unit  42   b  projects the first image  51  or the second image  52  generated by the image generation unit  42   a  on the screen  6  by controlling the projection device that can perform the projection among the first projection device  1  and the second projection device  2 . 
       FIG. 8  is a diagram showing an example of the attribute information of the content acquired by the acquisition unit  41  shown in  FIG. 7 . The acquisition unit  41  shown in  FIG. 7  acquires, for example, an attribute information table  80  for each content of the first image  51 . The attribute information table  80  is information indicating Keep_aspect, Always_disp, Type, Min_Size_rate, and Priority for each of the image content IMG 1 , the text contents TXT 1  and TXT 2 , and the operating part CTR 1  of the first image  51 . 
     Keep_aspect is the first attribute information described above, and indicates whether or not the aspect ratio is maintained in a case in which the size of the content is adjusted. Keep_aspect=1 indicates that the aspect ratio is maintained in a case in which the size of the content is adjusted, and Keep_aspect=0 indicates that the aspect ratio is made to be changeable in a case in which the size of the content is adjusted. 
     Always_disp is the second attribute information described above, and indicates whether or not the content is always projected in a state in which the projection by the partial projection device cannot be performed. Always_disp=1 indicates that projection is always performed in a state in which projection by the partial projection device is not possible, and Always_disp=0 indicates that the content is alternately projected with other contents in a state in which projection by the partial projection device is not possible. 
     Type is attribute information indicating the data type of the content. For example, Type of the image content IMG 1  is a “picture” indicating that it is the image data. Each Type of the text contents TXT 1  and TXT 2  is “text” indicating that it is the character data. Type of the operating part CTR 1  is “control” indicating that it is the operating part. 
     Min_Size_rate is attribute information indicating a rate of the adjusted size to the original content (minimum size rate), which is desirable to be maintained in a case in which the size of the content is adjusted. For example, in a case in which the size of the content is adjusted with Min_Size_rate=30%, it is desirable that the adjusted size does not fall below 30% of the size before the adjustment. 
     Priority is the third attribute information indicating the priority of displaying the content. For example, in a case in which the image content IMG 1 , the text contents TXT 1  and TXT 2 , and the operating part CTR 1  are disposed in the second image  52 , it is necessary to reduce at least any one of the contents, but the content having lower Priority among these contents is preferentially reduced. 
       FIG. 9  is a flowchart showing an example of attribute information setting processing by the control device  4 . The control device  4  executes, for example, the processing shown in  FIG. 9  as the attribute information setting processing of setting the attribute information of each content of the first image  51 . Specifically, the control device  4  executes the processing as follows for each content of the first image  51 . 
     First, the control device  4  determines whether or not a target content is the image data (step S 11 ). Here, the image data is not limited to still picture data, but may include motion picture data. In a case in which the target content is the image data (step S 11 : Yes), the control device  4  executes the attribute setting processing of the image data for the target content (step S 12 ), and terminates the processing for the target content. The attribute setting processing of the image data in step S 12  will be described with reference to  FIG. 10 . 
     In step S 11 , in a case in which the target content is not the image data (step S 11 : No), the control device  4  determines whether or not the target content is the character data (step S 13 ). In a case in which the target content is the character data (step S 13 : Yes), the control device  4  executes the attribute setting processing of the character data for the target content (step S 14 ), and terminates the processing for the target content. The attribute setting processing of the character data in step S 14  will be described with reference to  FIG. 11 . 
     In step S 13 , in a case in which the target content is not the character data (step S 13 : No), the target content is the operating part. In this case, the control device  4  executes the attribute setting processing of the operating part for the target content (step S 15 ), and terminates the processing for the target content. The attribute setting processing of the operating part in step S 15  will be described with reference to  FIG. 12 . 
     Note that there are data types other than the image data, the character data, and the operating part as the data type of the content, a conditional branch is further added and the attribute setting processing is executed depending on the data type of the content. 
     The processing shown in  FIG. 9  is executed, for example, at any point in time from the acquisition of the drawing data of the first image  51  by the control device  4  to the start of the projection of the second image  52  by the control device  4  in a state in which the partial projection device cannot perform the projection. For example, the processing shown in  FIG. 9  may be executed triggered by the failure of the partial projection device in the projection system  100 , or may be executed before the failure of the partial projection device in the projection system  100  occurs. 
     Each attribute information set by the processing shown in  FIG. 9  (for example, the attribute information table  80  shown in  FIG. 8 ) is stored in, for example, the storage medium  4   a.  in this case, the acquisition unit  41  shown in  FIG. 7  acquires each attribute information stored in the storage medium  4   a.    
       FIG. 10  is a flowchart showing an example of attribute setting processing of the image data shown in  FIG. 9 . As the attribute setting processing of the image data in step S 12  shown in  FIG. 9 , the control device  4  executes, for example, the processing shown in  FIG. 10 . First, the control device  4  sets Type of the target content to “picture” and Keep_aspect of the target content to “1” (step S 21 ). As described above, it is generally desirable to maintain the aspect ratio of the image data, and thus Keep_aspect is set to “1”. 
     Next, the control device  4  determines whether or not the target content is always projected (step S 22 ). The determination in step S 22  can be made based on various criteria, such as whether or not the target content is a motion picture, or whether or not the target content is a specific content that needs to reflect an interactive operation. As an example, it can be determined that the target content is always projected in a case in which the target content is the motion picture, and the target content is not always projected in a case in which the target content is a still picture. 
     In a case in which it is determined in step S 22  that the target content is always projected (step S 22 : Yes), the control device  4  sets Always_disp of the target content to “1” (step S 23 ). In a case in which it is determined that the target content is not always projected (step S 22 : No), the control device  4  sets Always_disp of the target content to “0” (step S 24 ). 
     Next, the control device  4  calculates a minimum size rate X in a case in which the size of the target content is adjusted, and sets the calculated minimum size rate X to Min_Size_rate of the target content (step S 25 ). For example, the calculation of the minimum size rate X can be performed based on various criteria, such as the number of pixels of the target content. 
     Next, the control device  4  determines priority Y of the display of the target content, sets the determined priority Y to Priority of the target content (step S 26 ), and terminates the attribute setting processing for the target content. For example, the determination of the priority Y in step S 26  can be made based on various criteria, such as a ratio of an area occupied by the target content in the first image  51 . As an example, the content having a larger ratio of the area in the first image  51  is more likely to be important content, so that the priority Y is set higher. 
     Note that an order of setting each attribute information shown in  FIG. 10  may be changed as appropriate. 
       FIG. 11  is a flowchart showing an example of attribute setting processing of the character data shown in  FIG. 9 . As the attribute setting processing of the character data in step S 14  shown in  FIG. 9 , the control device  4  executes, for example, the processing shown in  FIG. 11 . First, the control device  4  sets Type of the target content to “text” (step S 31 ). 
     Next, the control device  4  determines whether or not the aspect ratio is maintained in a case in which the size of the target content is adjusted (step S 32 ). The determination in step S 32  can be made based on various criteria, such as whether or not a font size is used properly in the target content which is the character data, or whether or not the character disposition, such as centering, is used properly. As an example, for content of which the font size is used properly, the layout of the character string is likely to be important, so that it is determined that the aspect ratio is maintained in a case in which the size is adjusted, and for content of which the font size is not used properly, the layout of the character string is likely not to be important, so that it is determined that the aspect ratio is not maintained in a case in which the size is adjusted. 
     In a case in which it is determined in step S 32  that the aspect ratio is maintained in a case in which the size of the target content is adjusted (step S 32 : Yes), the control device  4  sets Keep_aspect of the target content to “1” (step S 33 ). In a case in which it is determined that the aspect ratio is not maintained in a case in which the size of the target content is adjusted (step S 32 : No), the control device  4  sets Keep_aspect of the target content to “0” (step S 34 ). 
     Next, the control device  4  determines whether or not the target content is always projected (step S 35 ). The determination in step S 35  can be made based on various criteria, such as whether or not a display content of the target content is temporally changed, or whether or not the target content is a specific content that needs to reflect an interactive operation. As an example, in a case in which the display content of the target content is temporally changed, it can be determined that the projection is always performed, and in a case in which the display content of the target content is not temporally changed, it can be determined that the projection is not always performed. 
     In a case in which it is determined in step S 35  that the target content is always projected (step S 35 : Yes), the control device  4  sets Always_disp of the target content to “1” (step S 36 ). In a case in which it is determined that the target content is not always projected (step S 35 : No), the control device  4  sets Always_disp of the target content to “0” (step S 37 ). 
     Next, the control device  4  extracts a line breakable part in the target content which is the character data (step S 38 ). In step S 38 , for example, immediately after a punctuation mark in the character data can be extracted as the line breakable part. 
     Next, the control device  4  executes steps S 39  and S 40 , and terminates the attribute setting processing for the target content. Steps S 39  and S 40  are the same as steps S 25  and S 26  shown in  FIG. 10 . 
     Note that an order of setting each attribute information shown in  FIG. 11  may be changed as appropriate. 
       FIG. 12  is a flowchart showing an example of attribute setting processing of the operating part shown in  FIG. 9 . As the attribute setting processing of the operating part in step S 15  shown in  FIG. 9 , the control device  4  executes, for example, the processing shown in  FIG. 12 . First, the control device  4  sets Type of the target content to “control” (step S 51 ). 
     Next, the control device  4  determines whether or not the aspect ratio is maintained in a case in which the size of the target content is adjusted (step S 52 ). The determination in step S 52  can be made based on various criteria that can determine the importance of the aspect ratio, such as whether or not the operating part which is the target content is a gauge type (for example, a circular gauge type) operating part. 
     In a case in Which it is determined in step S 52  that the aspect ratio is maintained in a case in which the size of the target content is adjusted (step S 52 : Yes), the control device  4  sets Keep_aspect of the target content to “1” (step S 53 ). In a case in which it is determined that the aspect ratio is not maintained in a case in which the size of the target content is adjusted (step S 52 : No), the control device  4  sets Keep_aspect of the target content to “0” (step S 54 ). 
     Next, the control device  4  sets Always_disp of the target content to “1” (step S 55 ). As described above, it is generally desirable to always project the operating part, and thus Always_disp is set to “1”. 
     Next, the control device  4  executes steps S 56  and S 57 , and terminates the attribute setting processing for the target content. Steps S 56  and S 57  are the same as steps S 25  and S 26  shown in  FIG. 10 . 
     Note that an order of setting each attribute information shown in  FIG. 12  may be changed as appropriate. 
     In  FIGS. 9 to 12 , the method of setting the attribute information of each content in the first image  51  has been described, but the method of setting the attribute information of each content in the first image  51  may be optionally determined by the user of the projection system  100 . In addition, at least any one of the attribute information of each content in the first image  51  may be set in advance, for example, by a creator of the first image  51 . 
       FIG. 13  is a flowchart showing an example of projection control processing of the second image  52  by the control device  4 . In a case in which the drawing data of the first image  51  is set as the drawing data of the projection target, the control device  4  executes, for example, the projection control processing shown in  FIG. 13  in a case in which the projection by the partial projection device among the first projection device  1  and the second projection device  2  cannot be performed. Here, it is assumed that projection by the first projection device  1  cannot be performed due to the failure of the first projection device  1  or the like. 
     First, the control device  4  specifies the second system projection range  32  having the second device projection range  12  of the second projection device  2  that can perform the projection (step S 61 ). In addition, the control device  4  generates the empty second image  52  having the same shape and size as the specified second system projection range  32 . That is, in the second image  52  at this point in time, all of the regions are empty regions. 
     Next, the control device  4  extracts the content having Always_disp of “1” and Keep_aspect of “1” from each content of the first image  51  (step S 62 ). For example, in the example shown in  FIG. 8 , the image content IMG 1  is extracted in step S 62 . 
     Next, the control device  4  disposes the content extracted in step S 62  in the empty region of the second image  52  while maintaining the aspect ratio and reducing the content (step S 63 ). The content is reduced such that the rate of the reduced size to the size before reduction does not fall below Min_Size_rate of the content. 
     In a case in which a plurality of contents are extracted in step S 62 , the control device  4  refers to Type of each content and disposes the content of the image data, the content of the character data, and the content of the operating part in this order. As described above, the control device  4  disposes each content on the second image  52  in a priority order depending on the data type of each content. 
     In addition, in a case in which a plurality of contents haying the same Type are extracted in step S 62 , the control device  4  preferentially reduces the content having lower Priority, for the plurality of contents having the same Type. As described above, the control device  4  adjusts the size based on the priority of each content. 
     In addition, in a case in which the empty region of the second image  52  is insufficient and the content extracted in step S 62  cannot be disposed in the second image  52  while maintaining Min_Size_rate, the control device  4  reduces the content extracted in step S 62 . without maintaining Min_Size_rate until it can be disposed in the second image  52 . In this case, the control device  4  preferentially reduces the content having lower Priority. 
     Next, the control device  4  extracts the content having Always_disp of “1” and Keep_aspect of “0” from each content of the first image  51  (step S 64 ). For example, in the example shown in  FIG. 8 , the operating part CTR 1  is extracted in step S 64 . 
     Next, the control device  4  disposes the content extracted in step S 64  in the empty region of the second image  52  while reducing the content such that the aspect ratio is changeable (step S 65 ). The disposition of the content in step S 65  is the same as the disposition of the content in step S 63 , except that the aspect ratio is changeable. 
     Next, the control device  4  extracts the content having Always_disp of “0” and Keep_aspect of “1” from each content of the first image  51  (step S 66 ). For example, in the example shown in  FIG. 8 , the content is not extracted in step S 66 . 
     Next, the control device  4  disposes the content extracted in step S 66  in the empty region of the second image  52  to overlap with each other while maintaining the aspect ratio and reducing the content (step S 67 ). The disposition of the contents in step S 67  is the same as the disposition of the contents in step S 63 , except that the content and the empty region can overlap with each other. 
     Next, the control device  4  extracts the content having Always_disp of “0” and Keep_aspect of “0” from each content of the first image  51  (step S 68 ). For example, in the example shown in  FIG. 8 , the text contents TXT 1  and TXT 2  are extracted in step S 68 , 
     Next, the control device  4  disposes the content extracted in step S 68  in the empty region of the second image  52  to overlap with each other while reducing the content such that the aspect ratio is changeable (step S 69 ). The disposition of the contents in step S 69  is the same as the disposition of the contents in step S 65 , except that the content and the empty region can overlap with each other. Note that the content disposed in step S 69  may be disposed to overlap with the content disposed in step S 67  (Always_disp is “0”). 
     Next, the control device  4  projects the second image  52  in which each content is disposed onto the second system projection range  32  specified in step S 61  (step S 70 ), and terminates the series of the projection control processing. In step S 70 , the control device  4  always projects the content of which Always_disp is “1” disposed in the second image  52 . In addition, the control device  4  projects the content having Always_disp of 0 disposed in the overlapping region of the second image  52  while switching between the contents at regular time intervals. Note that even in a case of the content having Always_disp of 0 disposed in the second image  52 , the control device  4  always projects the content in a case in which no other contents are disposed in the overlapping region. 
     In  FIG. 13 , the method of disposing each content on the second image  52  has been described, but the disposition of each content in the first image  51  may also be performed by the method shown in  FIG. 13 . In this case, the drawing data of the first image  51  may not include the disposition information indicating the disposition of each content. 
       FIG. 14  is a schematic diagram showing a modification example of the projection system  100 . In addition to the configuration described, the projection system  100  may comprise a third projection device  8  and a fourth projection device  9 . The configurations of the third projection device  8  and the fourth projection device  9  are the same as the configurations of the first projection device  1  and the second projection device  2 . The control device  4  controls the projection by the third projection device  8  and the fourth projection device  9  in addition to the projection by the first projection device  1  and the second projection device  2 . 
     A third device projection range  13  is a projection range of the third projection device  8  on the screen  6 , and is a range different from the first device projection range  11  and the second device projection range  12 . A fourth device projection range  14  is a projection range of the fourth projection device  9  on the screen  6 , and is a range different from the first device projection range  11 , the second device projection range  12 , and the third device projection range  13 . In the example shown in  FIG. 14 , the first device projection range  11 , the second device projection range  12 , the third device projection range  13 , and the fourth device projection range  14  are ranges in which only some regions thereof overlap with each other. 
     In this case, the first system projection range  31  which constitutes the first projection range is a projection range having the first device projection range  11 , the second device projection range  12 , the third device projection range  13 , and the fourth device projection range  14 . Also in  FIG. 14 , for convenience of illustration, the first system projection range  31  is shown by a broken line frame slightly larger than an actual size. 
     The projection system  100  displays the projection target image onto the first system projection range  31  by projecting the division images by the first projection device  1 , the second projection device  2 , the third projection device  8 , and the fourth projection device  9 , respectively, and joining these four division images. The projection target image, which is projected onto the first system projection range  31  by the first projection device  1 , the second projection device  2 , the third projection device  8 , and the fourth projection device  9 , constitutes the first image. 
       FIG. 15  is a schematic diagram showing a state in which the projection is performed only by the first projection device  1 , the second projection device  2 , and the fourth projection device  9  shown in  FIG. 14 . For example, it is assumed that the projection onto the third device projection range  13  cannot be performed by the third projection device  8  due to a failure of the third projection device  8  or the like. In this case, the control device  4  performs the projection by using only the first projection device  1 , the second projection device  2 , and the fourth projection device  9  which can perform the projection. 
     In this case, the second system projection range  32  which constitutes the second projection range is a projection range having the first device projection range  11 , the second device projection range  12 , and the fourth device projection range  14 . Also in  FIG. 15 , for convenience of illustration, the second system projection range  32  is shown by a broken line frame slightly larger than an actual size. The second system projection range  32  is not limited to a rectangle, as in the example shown in  FIG. 15 . 
       FIG. 16  is a schematic diagram showing an example of the projection of the first image  51  by each projection device shown in  FIG. 14 . In a case in which all of the first projection device  1 , the second projection device  2 , the third projection device  8 , and the fourth projection device  9  can perform the projection, the control device  4  projects, for example, the first image  51  shown in  FIG. 16  onto the first system projection range  31  (first projection range) by these projection devices. 
       FIG. 17  is a schematic diagram showing an example of the projection of the second image  52  only by the first projection device  1 , the second projection device  2 , and the fourth projection device  9  shown in  FIG. 15 . For example, in a state in which the projection onto the third device projection range  13  by the third projection device  8  is not possible, and the projection can be performed only by the first projection device  1 , the second projection device  2 , and the fourth projection device  9  due to the failure of the third projection device  8  or the like, the control device  4  projects, for example, the second image  52  shown in  FIG. 17  onto the second system projection range  32  by these projection devices that can perform the projection. The second image  52  in this case is an image having the same shape and size as the second system projection range  32  having the first device projection range  11 , the second device projection range  12 , and the fourth device projection range  14 . 
     As shown in  FIGS. 14 to 17 , the number of projection devices in the projection system  100  is not limited to two, and may be four. In addition, the number of projection devices in the projection system  100  may be three, or five or more. 
       FIG. 18  is a schematic diagram showing another example of the projection of the second image  52  only by the first projection device  1 , the second projection device  2 , and the fourth projection device  9  shown in  FIG. 15 . A user  7  shown in  FIG. 18  is a user (for example, a viewer of a presentation by a slide show) who observes the projection target image projected onto the screen  6 . 
     The control device  4  may acquire range information indicating a range (range depending on the position of the user) relatively close to the user  7  in the second system projection range  32 . In the example shown in  FIG. 18 , the range of the second system projection range  32  that is relatively close to the user  7  is, for example, a range of the second system projection range  32  having the fourth device projection range  14  shown in  FIG. 15 . The range information may be acquired, for example, based on the image obtained by the imaging by the imaging unit  5 , may be acquired by user input, or may be acquired by another method. 
     In a case in which the control device  4  generates the second image  52 , the control device  4  may preferentially dispose the content having a higher priority (Priority) in a region corresponding to the range in the second image  52  indicated by the range information based on the acquired range information. As a result, it is possible to project the content having a high priority to be close to the user  7  to improve the visibility. 
     As described above, in the present embodiment, the first attribute information, which is associated with the content and indicates whether or not an aspect ratio is made to be changeable in a case in which a size of the content is adjusted, is acquired by focusing on the fact that some of the contents disposed in the projected first image is important to maintain the aspect ratio, while others are not. 
     Moreover, in a case in which the partial projection device cannot perform the projection, the second image in which at least a part of the contents of the first image is disposed is projected onto the projectable range by the remaining projection device, and the size of the content in the second image is adjusted based on the first attribute information. As a result, the content in which the maintenance of the aspect ratio is important can be disposed in the second image by adjusting the size while maintaining the aspect ratio, and the content in which the maintenance of the aspect ratio is not important can be disposed in the second image by adjusting the size such that the aspect ratio is changeable. 
     Therefore, it is possible to flexibly dispose the content in which the maintenance of the aspect ratio is not important in the empty region of the second image while suppressing the decrease in the visibility of the content in which the maintenance of the aspect ratio is important. Therefore, even in a state in which the partial projection device cannot perform the projection, it is possible to project the second image for efficiently performing the information display onto the projectable region. 
     In addition in the present embodiment, the second attribute information, which is associated with the content and indicates whether the content is always projected or is alternately projected with other contents in a state in which the partial projection device cannot perform the projection, is acquired by focusing on the fact that some of the contents disposed in the projected first image need to be always displayed, while others are not. 
     Moreover, in a state in which the partial projection device cannot perform the projection, the second image in which at least a part of the contents of the first image is disposed is projected onto the projectable range by the remaining projection device, the content associated with the second attribute information indicating that the content is always projected is always projected in the projection of the second image, and the content associated with the second attribute information indicating that the content is alternately projected with other contents is alternately projected with other contents. 
     As a result, by alternately projecting the contents that do not need to be always displayed, the contents can be disposed larger with respect to the second image, or more contents can be disposed with respect to the second image. Therefore, even in a state in which the partial projection device cannot perform the projection, efficient information display can be performed. 
     In addition, in the present embodiment, the third attribute information indicating the display priority of each content is acquired. Moreover, in the generation of the second image, the size of the content is adjusted based on the third attribute information. As a result, it is possible to preferentially reduce and dispose the content having a low display priority in the second image. Therefore, it is possible to suppress the decrease in the visibility of the content having a high display priority. 
     (Other Modification Examples of Present Embodiment) 
     For example, as in the example shown in  FIG. 15 , in a case in which the second system projection range  32  includes a plurality of device projection ranges, the control device  4  may specify the device projection range of the projection device having a highest resolution. Moreover, the control device  4  may preferentially dispose the content having a higher priority (Priority) in the region corresponding to the specified device projection range in the second image  52 . As a result, it possible to project the content having a high priority from the projection device having a high resolution to improve the visibility. 
     In addition, the control device  4  may designate the region of the content having Always_disp of 1, in which the projection is not performed, in a case in which the projection by the partial projection device cannot be performed. As a result, the region of the second image  52  onto which other contents can be projected is increased, so that more information can be projected. 
     In addition, the control device  4  may execute the processing of increasing the contrast of the content in a case in which the content having a priority of a certain value or higher is reduced and disposed in the second image. As a result, the decrease in the visibility due to the reduction of the important content can be compensated for by high contrast. 
     In addition, in a case in which the projection by the partial projection device cannot be performed and the second image  52  is displayed, the control device  4  may receive an instruction for size adjustment with respect to each content of the second image  52  from the user, and adjust the size of the content of the second image  52  depending on the result thereof. As a result, it is possible for the user to adjust the size of the content of the second image  52 . 
     In addition, in the unsteady state in which the partial projection device in the projection system  100  cannot perform the projection, the control device  4  may output information indicating the unsteady state to the user. As a result, it is possible for the user to recognize that the partial projection device in the projection system  100  is in the unsteady state in which projection cannot be performed, and take measures, such as repair. 
     In addition, as in the example shown in  FIG. 8 , the configuration has been described in which the attribute information of the content is set for each content, but the attribute information of the content can be information of various forms as long as the information is associated with the content. For example, the first attribute information (Keep_aspect) may be a list of the contents in which the aspect ratio is maintained in a case in which the size of each content of the first image  51  is adjusted, or a list of the contents in which the aspect ratio is changeable in a case in which the size of each content of the first image  51  is adjusted. 
     In addition, although the case has been described in which the reduction is mainly performed as the size adjustment of the content in a case of generating the second image  52 , the size adjustment is not limited to the reduction. That is, for example, in the processing shown in  FIG. 13 , in a case in which the empty region of the second image  52  is large in a case in which a certain content is disposed, the content may be disposed while maintaining the size of the content, or the content may be enlarged and disposed. 
     At least the following matters are described in the present specification. 
     (1) 
     A control device that controls projection by a plurality of projection units having different projection ranges, the device comprising a control unit that projects, by the plurality of projection units, a first image in which a content is disposed onto a first projection range having the projection ranges of the plurality of projection units, and an acquisition unit that acquires first attribute information which is associated with the content and indicates whether an aspect ratio is made to be changeable or is maintained in a case in which a size of the content is adjusted, in which the control unit projects a second image in which at least a part of the contents is disposed onto a second projection range having a projection range of a projection unit excluding a part of projection units among the plurality of projection units, and adjusts the size of the content in generation of the second image based on the first attribute information in a state in which projection is performed by the projection unit excluding the part of projection units among the plurality of projection units. 
     (2) 
     The control device according to (1), in which the state in which projection is performed by the projection unit excluding the part of projection units among the plurality of projection units is a state in which the part of projection units is in an unsteady state. 
     (3) 
     The control device according to (2), in which the control device gives a notification of information indicating the unsteady state in a case in which the part of projection units is in the unsteady state. 
     (4) 
     The control device according to any one of (1) to (3), in which, in generation of the second image, the control unit adjusts the size of the content associated with the first attribute information indicating that the aspect ratio is made to be changeable in a case in which the size is adjusted such that the aspect ratio is changeable, and adjusts the size of the content associated with the first attribute information indicating that the aspect ratio is maintained in a case in which the size is adjusted while maintaining the aspect ratio. 
     (5) 
     The control device according to any one of (1) to (4), in which the acquisition unit acquires second attribute information which is associated with the content and indicates whether the content is always projected or is alternately projected with other contents in the state in which projection is performed by the projection unit excluding the part of projection units among the plurality of projection units, and the control unit performs generation and projection of the second image based on the second attribute information. 
     (6) 
     The control device according to (5), in which, in projection of the second image, the control unit always projects the content associated with the second attribute information indicating that the content is always projected, and alternately projects the content, with other contents, associated with the second attribute information indicating that the content is alternately projected with the other contents in the state in which projection is performed by the projection unit excluding the part of projection units among the plurality of projection units. 
     (7) 
     The control device according to any one of (1) to (6), in which the content includes a plurality of contents, the acquisition unit acquires third attribute information indicating at least two or more priorities of the plurality of contents, and in generation of the second image, the control unit adjusts the size of the content based on the third attribute information. 
     (8) 
     The control device according to any one of (1) to (7), in which the content includes a plurality of contents, and the control unit disposes the plurality of contents in the second image in a priority order depending on at least two or more data types of the plurality of contents. 
     (9) 
     The control device according to any one of (1) to (8), in which the control unit disposes a reduced content in the second image by increasing a contrast of the reduced content. 
     (10) 
     The control device according to any one of (1) to (9), in which the content includes a plurality of contents, the acquisition unit acquires third attribute information indicating at least two or more priorities of the plurality of contents, and in generation of the second image, the control unit preferentially disposes a content having a higher priority in a region of the second image corresponding to a range in the second projection range corresponding to a position of a user who observes the projection range based on range information indicating the range corresponding to the position of the user and the third attribute information. 
     (11) 
     The control device according to any one of (1) to (10), in which the content includes a plurality of contents, the acquisition unit acquires third attribute information indicating at least two or more priorities of the plurality of contents, and in generation of the second image, the control unit preferentially disposes a content having a higher priority in a region of the second image corresponding to a projection unit having a highest resolution among two or more projection units based on the third attribute information in a case in which the projection unit excluding the part of projection units among the plurality of projection units includes the two or more projection units. 
     (12) 
     A control method of controlling projection by a plurality of projection units having different projection ranges, the method comprising a control step of projecting, by the plurality of projection units, a first image in which a content is disposed onto a first projection range having the projection ranges of the plurality of projection units, and an acquisition step of acquiring first attribute information which is associated with the content and indicates whether an aspect ratio is made to be changeable or is maintained in a case in which a size of the content is adjusted, in which in the control step, a second image in which at least a part of the contents is disposed is projected onto a second projection range having a projection range of a projection unit excluding a part of projection units among the plurality of projection units, and the size of the content is adjusted in generation of the second image based on the first attribute information in a state in which projection is performed by the projection unit excluding the part of projection units among the plurality of projection units. 
     (13) 
     The control method according to (12), in which the state in which projection is performed by the projection unit excluding the part of projection units among the plurality of projection units is a state in which the part of projection units is in an unsteady state. 
     (14) 
     The control method according to (13), in which a notification of information indicating the unsteady state is given in a case in which the part of projection units is in the unsteady state. 
     (15) 
     The control method according to any one of (12) to (14), in which, in generation of the second image, in the control step, the size of the content associated with the first attribute information indicating that the aspect ratio is made to be changeable in a case in which the size is adjusted is adjusted such that the aspect ratio is changeable, and the size of the content associated with the first attribute information indicating that the aspect ratio is maintained in a case in which the size is adjusted is adjusted while maintaining the aspect ratio. 
     (16) 
     The control method according to any one of (12) to (15), in which in the acquisition step, second attribute information which is associated with the content and indicates whether the content is always projected or is alternately projected with other contents in the state in which projection is performed by the projection unit excluding the part of projection units among the plurality of projection units, is acquired, and in the control step, generation and projection of the second image are performed based on the second attribute information. 
     (17) 
     The control method according to (16), in which, in projection of the second image, in the control step, the content associated with the second attribute information indicating that the content is always projected is always projected, and the content associated with the second attribute information indicating that the content is alternately projected with other contents is alternately projected with the other contents in the state in which projection is performed by the projection unit excluding the part of projection units among the plurality of projection units. 
     (18) 
     The control method according to any one of (12) to (17), in which the content includes a plurality of contents, in the acquisition step, third attribute information indicating at least two or more priorities of the plurality of contents is acquired, and in generation of the second image, in the control step, the size of the content is adjusted based on the third attribute information. 
     (19) 
     The control method according to any one of (12) to (18), in which the content includes a plurality of contents, and in the control step, the plurality of contents are disposed in the second image in a priority order depending on at least two or more data. types of the plurality of contents. 
     (20) 
     The control method according to any one of (12) to (19), in which in the control step, a reduced content is disposed in the second image by increasing a contrast of the reduced content. 
     (21) 
     The control method according to any one of (12) to (20), in which the content includes a plurality of contents, in the acquisition step, third attribute information indicating at least two or more priorities of the plurality of contents is acquired, and in generation of the second image, in the control step, a content having a higher priority in a region of the second image corresponding to a range in the second projection range corresponding to a position of a user who observes the projection range is preferentially disposed based on range information indicating the range corresponding to the position of the user and the third attribute information. 
     (22) 
     The control method according to any one of (12) to (21), in which the content includes a plurality of contents, in the acquisition step, third attribute information indicating at least two or more priorities of the plurality of contents is acquired, and in generation of the second image, in the control step, a content having a higher priority is preferentially disposed in a region of the second image corresponding to a projection unit having a highest resolution among two or more projection units based on the third attribute information in a case in which the projection unit excluding the part of projection units among the plurality of projection units includes the two or more projection units. 
     (23) 
     A control program causing a computer to function as the acquisition unit and the control unit of the control device according to any one of (1) to (11). 
     (24) 
     A projection system comprising the control device according to any one of (1) to (11), and the plurality of projection units. 
     Various embodiments have been described above with reference to the drawings, but it is needless to say that the present invention is not limited thereto. It is obvious that those skilled in the art can conceive various changes or modifications within the scope described in the claims, and naturally, such changes or modifications also belong to the technical scope of the present invention. In addition, the components in the embodiments described above may be optionally combined without departing from the spirit of the invention. 
     Note that the present application is based on a Japanese patent application filed on Sep. 27, 2019 (JP2019-177951), the contents of which are incorporated herein by reference. 
     EXPLANATION OF REFERENCES 
     
         
         
           
               1 : first projection device 
               2 : second projection device 
               4 : control device 
               4   a : storage medium 
               5 : imaging unit 
               6 : screen 
               7 : user 
               8 : third projection device 
               9 : fourth projection device 
               11 : first device projection range 
               12 : second device projection range 
               13 : third device projection range 
               14 : fourth device projection range 
               21 : display unit 
               21   a : light source 
               21   b : optical modulation unit 
               22 : projection optical system 
               23 : projection unit 
               24 ,  42 : control unit 
               31 : first system projection range 
               32 : second system projection range 
               41 : acquisition unit 
               42   a : image generation unit 
               42   b : projection control unit 
               51 : first image 
               52 : second image 
               61 ,  62 : projection state 
               80 : attribute information table 
               100 : projection system 
             IMG 1 : image content 
             TXT 1  TXT 2 : text content 
             CTR 1 : operating part