Patent Publication Number: US-2022217438-A1

Title: Display control device, display control method, and program

Description:
TECHNICAL FIELD 
     The present disclosure relates to a display control device, a display control method, and a program. The present disclosure particularly relates to a display control device, a display control method, and a program 
     that enable improvement of the user experience of a user who views and listens to content hierarchically including a plurality of partial pictures and an entire picture including the plurality of partial pictures as regions. 
     BACKGROUND ART 
     Conventionally, content is distributed such that an entire picture, such as an entire-celestial-spherical or omnidirectional picture or a panoramic picture, is reproduced and the display region of the entire picture is moved or switched in response to an operation from a user, resulting in display of a high-definition partial picture hierarchically arranged at part of the entire picture. 
     For example, as disclosed in Non-Patent Document 1, format for preparing a low-resolution entire-celestial-spherical and all-directional picture and high-definition pictures hierarchically divided in the picture, has been prescribed.  
     CITATION LIST 
     Non-Patent Document 
     Non-Patent Document 1: Information technology—Coded representation of immersive media (MPEG-I)—Part 2: Omnidirectional media format 
     SUMMARY OF THE INVENTION 
     Problems to be Solved by the Invention 
     By the way, in reproduction of such content as described above, a user performs operations to the content while viewing and listening to a low-resolution entire picture such that an area that the user desires to view and listen to in more detail is zoomed and a high-resolution partial picture in the area is selected, resulting in a request for distribution thereof. However, in some cases, no high-resolution partial pictures are present in practice in the area zoomed by the user having been viewing and listening to the low-resolution entire picture, and thus the operation to the content results in waste. Therefore, improvement of user experience is required with acquisition of favorable operability to such content. 
     The present disclosure has been made in consideration of such a situation, and an object of the present disclosure is to enable improvement of the user experience of a user who views and listens to content hierarchically including a plurality of partial pictures  and an entire picture including the plurality of partial pictures as regions. 
     Solutions to Problems 
     According to one aspect of the present disclosure, provided is a display control device including: a superimposition-data generation unit configured to generate, in reproduction of content hierarchically including a plurality of high-definition partial pictures and a low-resolution entire picture including the plurality of partial pictures as regions, superimposition data to be superimposed onto the entire picture, on the basis of metadata regarding the partial pictures; a display-picture generation unit configured to generate a display picture in which a picture based on the superimposition data is superimposed on the entire picture; and a request transmission unit configured to transmit a request for distribution of a desired partial picture selected from the partial pictures with the display picture. 
     According to one aspect of the present disclosure, provided is a display control method or a program including: generating, in reproduction of content hierarchically including a plurality of high-definition partial pictures and a low-resolution entire picture including the plurality of partial pictures as regions, superimposition data to be superimposed onto the entire picture, on the basis of metadata regarding the partial pictures; generating a display picture in which a picture  based on the superimposition data is superimposed on the entire picture; and transmitting a request for distribution of a desired partial picture selected from the partial pictures with the display picture. 
     According to one aspect of the present disclosure, in reproduction of content hierarchically including a plurality of high-definition partial pictures and a low-resolution entire picture including the plurality of partial pictures as regions, superimposition data to be superimposed onto the entire picture is generated, on the basis of metadata regarding the partial pictures. Generated is a display picture in which a picture based on the superimposition data is superimposed on the entire picture. Transmitted is a request for distribution of a desired partial picture selected with the display picture. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a block diagram of an exemplary configuration of a content distribution system according to a first embodiment to which the present technology is applied. 
         FIG. 2  is an explanatory view of display modes of low-resolution entire pictures. 
         FIG. 3  is an explanatory view of a user interface on which high-resolution areas are superimposed on a low-resolution entire picture. 
         FIG. 4  is an explanatory view of user interfaces according to modifications.  
         FIG. 5  is as explanatory view of user interfaces according to modifications. 
         FIG. 6  is an explanatory view of user interfaces according to modifications. 
         FIG. 7  is a block diagram of an exemplary configuration of a mobile display device. 
         FIG. 8  is an explanatory flowchart of first content distribution processing. 
         FIG. 9  is as explanatory flowchart of second content distribution processing. 
         FIG. 10  is an explanatory flowchart of third content distribution processing. 
         FIG. 11  is an explanatory flowchart of fourth content distribution processing. 
         FIG. 12  is an explanatory flowchart of fifth content distribution processing. 
         FIG. 13  is an explanatory flowchart of processing of requesting generation of a high-resolution partial picture. 
         FIG. 14  is an explanatory flowchart of sixth content distribution processing. 
         FIG. 15  is a block diagram of an exemplary configuration of a content distribution system according to a second embodiment to which the present technology is applied. 
         FIG. 16  is an explanatory view of a first exemplary operation to content with a remote controller. 
         FIG. 17  is ac explanatory view of a second exemplary operation to content with the remote controller. 
         FIG. 18  is an explanatory view of a third exemplary  operation to content with the remote controller. 
         FIG. 19  is an explanatory view of exemplary allocation of functions to existing buttons of the remote controller. 
         FIG. 20  is an explanatory view of operation units for spatial control. 
         FIG. 21  is a block diagram of an exemplary configuration of a large-screen display device. 
         FIG. 22  is an explanatory flowchart of seventh content distribution processing. 
         FIG. 23  is a block diagram of an exemplary configuration of a computer according to an embodiment to which the present technology is applied. 
     
    
    
     MODE FOR CARRYING OUT THE INVENTION 
     Specific embodiments to which the present technology is applied, will be described in detail below with reference to the drawings. 
     First Exemplary Configuration of Content Distribution System 
       FIG. 1  is a block diagram of an exemplary configuration of a content distribution system according to a first embodiment to which the present technology is applied. 
     The content distribution system  11  illustrated in  FIG. 1  includes a mobile display device  13 , a large-screen display device  14 , and a distribution server  15  connected through a network  12 . The distribution server   15  is connected with a content storage unit  16 . 
     The mobile display device  13  is, for example, a portable and compact display device including a touch panel display capable of displaying a picture and additionally accepting a touch operation from a user. Furthermore, the mobile display device  13  is capable of performing direct wireless communication with the large-screen display device  14  and additionally performing communication with the distribution server  15  through the network  12 . Note that, as the mobile display device  13 , in addition to use of a so-called tablet-type information processing device, various types of display devices capable of displaying a picture in response to an operation from a user can be used, such as a personal computer, a stationary large-screen television receiver, a projector, and the like. 
     The large-screen display device  14  is, for example, a large-size display device capable of displaying a high-definition picture. The large-screen display device  14  is capable of performing direct wireless communication with the mobile display device  13  and additionally performing communication with the distribution server  15  through the network  12 . As the large-screen display device  14 , for example, a stationary large-screen television receiver, a projector, or the like can be used. 
     The distribution server  15  includes a plurality of server groups connected to the network  12  and provides,  on the network  12 , a service of distributing content read from the content storage unit  16 . 
     The content storage unit  16  stores content to be distributed in the content distribution system  11 . Content stored in the content storage unit  16  includes, for example, a low-resolution entire picture and hierarchically divided high-resolution partial pictures and has a manifest describing various types of information necessary for control of distribution thereof. 
     In the content distribution system  11  having such a configuration, a user operates the mobile display device  13  and selects a high-resolution partial picture from a low-resolution entire picture displayed on the mobile display device  13 , so that the high-resolution partial picture can be displayed on the mobile display device  13  or the large-screen display device  14 . 
     For example, in a case where distribution control of content and display of a high-resolution partial picture are performed by the same equipment, the high-resolution partial picture is displayed on the mobile display device  13 . In this case, the content distribution system  11  may exclude the large-screen display device  14 . Meanwhile, in a case where distribution control of content and display of a high-resolution partial picture are performed by different pieces of equipment, the high-resolution partial picture is displayed on the large-screen display device  14 .  
     The display mode of a low-resolution entire picture that is distributed in the content distribution system  11 , will be described with reference to  FIG. 2 . 
     In the content distribution system.  11 , a low-resolution entire picture is distributed in a display mode pursuant to, for example, such equirectangular (ER) projection as illustrated in A of  FIG. 2  or such azimuthal equidistant projection as illustrated in B of 
       FIG. 2 . 
     For example, in a case where a low-resolution entire picture in the display mode pursuant to the equirectangular projection has been displayed on the mobile display device  13 , the user can perform operations to the touch panel display of the mobile display device  13  such that the low-resolution entire picture is subjected to scaling and translation. Furthermore, in a case where a low-resolution entire picture in the display mode pursuant to the azimuthal equidistant projection has been displayed on the mobile display device  13 , the user can perform operations to the touch panel display of the mobile display device  13  such that the low-resolution entire picture is subjected to scaling and spherical rotation. This arrangement enables the user to grasp the entire image of an entire celestial sphere exhibited by the low-resolution entire picture. 
     A user interface for selection of a high-resolution partial picture from a low-resolution entire picture,  will be described with reference to  FIG. 3 . 
     For example, the mobile display device  13  acquires a low-resolution entire picture based on such equirectangular projection as illustrated in the upper part of  FIG. 3  together with information regarding prepared high-resolution partial pictures (hereinafter, referred to as picture metadata). For example, as the picture metadata, the Media Presentation Description (MPD) of Moving Picture Experts Group Dynamic Adaptive Streaming over HTTP (MPEG DASH) can be used. 
     Then, on the basis of the picture metadata, the mobile display device  13  superimposition-displays high-resolution areas (hatched areas in the example of  FIG. 3 ) on the low-resolution entire picture such that the areas where the high-resolution partial pictures are present are enclosed, as illustrated in the middle part of  FIG. 3 . 
     Moreover, when the user performs an operation to the touch panel display of the mobile display device  13  such that a high-resolution area is enlargement-displayed, the mobile display device  13  displays respective indices of high-resolution partial pictures selectably, as illustrated in the lower part of  FIG. 3 . In the example of  FIG. 3 , respective frames representing the high-resolution partial pictures are displayed at the locations at which the high-resolution partial pictures are disposed. The index numbers (1 to 5) are denoted in the frames.  
     Thus, when the user selects a desired high-resolution partial picture the user desires to view and listen to from the indices of the high-resolution partial pictures, the mobile display device  13  transmits a viewing/listening request for distribution of the high-resolution partial picture to the distribution server  15 . When the distribution server  15  transmits the high-resolution partial picture in response to the viewing/listening request, the mobile display device  13  receives and displays the high-resolution partial picture, so that the user can view and listen to the desired high-resolution partial picture. 
     Moreover, in a case where the user desires to view and listen to another high-resolution partial picture, the user performs an operation similar to the above again after performing an operation of returning the display of the mobile display device  13  to the low-resolution entire picture, so that the user can selectively view and listen to the desired high-resolution partial picture. 
     As above, in the content distribution system  11 , adoption of the user interface on which high-resolution areas are superimposition-displayed onto a low-resolution entire picture enables the user to recognize the areas where the high-resolution partial pictures are present before zooming the low-resolution entire picture. Therefore, in the content distribution system  11 , the user can avoid performing a waste operation, such as zooming any area where no high-resolution partial  pictures are present. 
     Therefore, in reproduction of content having a low-resolution entire picture and high-resolution partial pictures prepared, the content distribution system  11  enables the user to request distribution of a desired high-resolution partial picture, with favorable operability, resulting in improvement of user experience. 
     Note that the content distribution system  11  may adopt another user interface. 
     User interfaces for selection of a high-resolution partial picture from a low-resolution entire picture, according to modifications, will be described with 
     reference to  FIGS. 4 to 6 . 
     On the user interface illustrated in A of  FIG. 4 , at places at which a plurality of high-resolution partial pictures is present to a low-resolution entire picture, respective thumbnail images of the corresponding high-resolution partial pictures are displayed selectably. For example, the user performs a touch operation to any of the thumbnail images, so that the high-resolution partial picture to be displayed can be selected. 
     Furthermore, in addition to display of such thumbnail images, for example, respective indices of the high-resolution partial pictures denoted with such index numbers as illustrated in  FIG. 3  may be displayed. As above, in a case where index numbers are used, for  example, the high-resolution partial picture to be displayed can be sequentially selected in the order of index numbers. 
     Furthermore, regarding the place at which each high-resolution partial picture is present, in a case where a predetermined number of high-resolution partial pictures different in resolution (high-definition level) are present at the same place, as Illustrated in B of  FIG. 4 , in indicating the number of high-resolution part al pictures is denoted on each individual thumbnail image. That is, in B of  FIG. 4 , the thumbnail image denoted with “×2” indicates that two high-resolution partial pictures different in resolution. are present, and the thumbnail image denoted with “×3” indicates that three high-resolution partial pictures different in resolution are present. 
     Then, in a case where a predetermined number of high-resolution partial pictures different in resolution are present at the same place, use of such a user interface as illustrated in C of  FIG. 4  enables any resolution to be selected for the high-resolution partial picture to be displayed. In the example illustrated in C of  FIG. 4 , a pop-up menu having popped up from the thumbnail image of a high-resolution partial picture indicates that, among three resolutions of an ultra high-definition picture, a high-definition picture, and a midrange high-definition picture, the high-definition picture has been selected.  
     Note that, for example, adopted may be a user interface on which respective thumbnail images of a predetermined number of high-resolution partial pictures are displayed in a multilayered mode and a desired-resolution high-resolution partial picture is specified by sequentially turning the thumbnail images from the top. 
     Furthermore, as illustrated in  FIG. 5 , markers based on luminance (e.g., brightness or difference in contrast) that a low-resolution entire picture does not have, may be displayed at places at which high-resolution partial pictures are present on the low-resolution entire picture. A of  FIG. 5  exemplifies display of star markers, and B of  FIG. 5  exemplifies circular markers. Moreover, the markers may blink on and off due to a special effect, resulting in being more noticeable. 
     Furthermore, as illustrated in A of  FIG. 6 , in each area where high-resolution partial pictures are present, a shape (three-dimensionally bar-chart shape) representing height corresponding to the number of high-resolution partial pictures present in the corresponding area may be displayed on a low-resolution entire picture. Furthermore, as illustrated in B of  FIG. 6 , a so-called heat map indicating density such that an area including a large number of high-resolution partial pictures is deep and an area including a small number of high-resolution partial pictures light, may be displayed on a low-resolution entire picture.  
     Furthermore, as illustrated in C of  FIG. 6 , each high-resolution area in which the areas where high-resolution partial pictures are present are enclosed may be displayed, on a low-resolution entire picture, with depth (or brightness) corresponding to the number of high-resolution partial pictures present in the corresponding high-resolution area. For example, the deepest high-resolution area indicates the largest number of high-resolution partial pictures, the second deepest high-resolution area indicates the second largest number of high-resolution partial pictures, and the lightest high-resolution area indicates the smallest number of high-resolution partial pictures. 
     Then, when an operation of enlargement display is performed to such a low-resolution entire picture as illustrated in  FIG. 5 or 6 , frames representing respective high-resolution partial pictures, denoted with such index numbers as illustrated on the lower side of  FIG. 3 , are displayed selectably. 
     Exemplary Configuration of Mobile Display Device 
       FIG. 7  is a block diagram of an exemplary configuration of the mobile display device  13 . 
     As illustrated in  FIG. 7 , the mobile display device  13  includes a user-operation detection unit  21 , a control-information acquisition unit  22 , a control-information analysis unit  23 , a reception-request generation unit  24 , a request transmission unit  25 , a picture reception unit  26 , a picture-metadata reception  unit  27 , a superimposition-data generation unit  28 , a display-picture generation unit  29 , and a display unit  30 . 
     The user-operation detection unit  21  is, for example, a touch-operation input sensor for the touch panel display. The user-operation detection unit  21  detects a user operation to the mobile display device  13  and notifies the control-information acquisition unit  22  of the user operation. 
     In accordance with the user operation from the user-operation detection unit  21 , the control-information acquisition unit  22  acquires, for example, control information indicating user&#39;s operation description (e.g., enlargement display, selection of a high-resolution partial picture, or return to the low-resolution entire picture). 
     The control-information analysis unit  23  analyzes the control information acquired by the control-information acquisition unit  22  or picture metadata received by the picture-metadata reception unit  27 . 
     The reception-request generation unit  24  generates a viewing/listening request for distribution of the high-resolution partial picture determined by the user operation. The request transmission unit  25  transmits the viewing/listening request generated by the reception-request generation unit  24 , to the distribution server  15  through the network  12 . 
     The picture reception unit  26  receives the low-resolution entire picture or the high-resolution partial picture transmitted from the distribution server  15  through the network  12  and then supplies the low-resolution entire picture or the high-resolution partial picture to the display-picture generation unit  29 . 
     The picture-metadata reception unit  27  receives the picture metadata transmitted from the distribution server  15  through the network  12  and then supplies the picture metadata to the superimposition-data generation unit  28 . 
     On the basis of the picture metadata received by the picture-metadata reception unit  27 , the superimposition-data generation unit  28  generates superimposition data to be superimposed onto the low-resolution entire picture received by the picture reception unit  26 . For example, the superimposition-data generation unit  28  generates, as the superimposition data, such high-resolution areas as illustrated in the middle part of  FIG. 3 , such indices of high-resolution partial pictures as illustrated in the lower part of  FIG. 3 , such thumbnail images of high-resolution partial pictures as illustrated in  FIG. 4 , or the like. 
     The display-picture generation unit  29  generates a display picture in which the low-resolution entire picture or the high-resolution partial picture received  by the picture reception unit  26  is adapted to the size of view and resolution of the display unit  30 , and then the display unit  30  displays the display picture. Furthermore, on the basis of the superimposition data generated by the superimposition-data generation unit  28 , the display-picture generation unit  29  generates, for example, a display picture in which the high-resolution areas are superimposed on the low-resolution entire picture, a display picture in which the indices of the high-resolution partial pictures are superimposed on the low-resolution entire picture, a display picture in which the thumbnail images of the high-resolution partial pictures are superimposed on the low-resolution entire picture, or the like. 
     The display unit  30  is, for example, a display for the touch panel display, and displays the display picture generated by the display-picture generation unit.  29 . 
     First Content Distribution Processing 
     First content distribution processing that is performed in the content distribution system  11  will be exemplarily described with reference to a flowchart illustrated in  FIG. 8 . 
     In step S 11 , the picture reception unit  26  of the mobile display device  13  receives a low-resolution entire picture transmitted from the distribution server  15  and the picture-metadata reception unit  27  of the mobile display device  13  receives picture metadata transmitted from the distribution server  15 .  
     In step  812 , the control-information analysis unit  23  of the mobile display device  13  analyzes the picture metadata received by the picture-metadata reception unit  27  in step S 11 . 
     In step S 13 , in accordance with an analytical result from the control-information analysis unit  23  in step S 12 , the mobile display device  13  determines whether or not any hierarchically divided high-resolution partial pictures are present to the low-resolution entire picture received in step S 11 . 
     In step S 13 , in a case where the mobile display device  13  determines that no high-resolution partial pictures are present, the processing proceeds to step S 14 . 
     In step S 14 , the display-picture generation unit  29  of the mobile display device  13  generates a display picture such that the low-resolution entire picture received by the picture reception unit  26  in step S 11  is adapted to the size of view and resolution of the display unit  30 . Then, after the display unit  30  of the mobile display device  13  displays the low-resolution entire picture, the processing goes back to step S 11 . After that, similar processing is repeatedly performed. 
     Meanwhile, in step S 13 , in a case where the mobile display device  13  determines that high-resolution partial pictures are present, the processing proceeds to step  S 15 . 
     In step S 15 , on the basis of the picture metadata received by the picture-metadata reception unit  27  in step S 11 , the superimposition-data generation unit  28  of the mobile display device  13  generates, as superimposition data, high-resolution areas to be superimposed onto the low-resolution entire picture. 
     In step S 16 , the display-picture generation unit  29  of the mobile display device  13  generates a display picture in which the high-resolution areas based on the superimposition data generated by the superimposition-data generation unit  28  are superimposed on the low-resolution entire picture received by the picture reception unit  26 . Thus, the mobile display device  13  can display, on the display unit  30 , the low-resolution entire picture on which the high-resolution areas are superimposed, as illustrated in the middle part of  FIG. 3 . Therefore, in a case where the user desires to view and listen to a high-resolution partial picture in a high-resolution area, the user can perform an operation of enlargement-displaying the high-resolution area. 
     In step S 17 , on the basis of control information acquired by the control-information acquisition unit  22  in accordance with a user operation detected by the user-operation detection unit  2 , the mobile display device  13  determines whether or not an operation of enlargement-displaying a high-resolution area has been performed.  
     In step  317 , in a case where the mobile display, device  13  determines that no operation of enlargement-displaying a high-resolution area has been performed, the processing goes back to step S 11 . After that, similar processing is repeatedly performed. Meanwhile, in step S 17 , in a case where the mobile display device  13  determines that an operation of enlargement-displaying a high-resolution area has been performed, the processing proceeds to step S 18 . 
     In step S 18 , in accordance with the user operation detected by the user-operation detection unit  21 , the display-picture generation unit  29  of the mobile display device  13  generates a display picture such that the low-resolution entire picture is enlarged and additionally respective indices of the high-resolution partial pictures are displayed. Thus, the mobile display device  13  can display the indices of the high-resolution partial pictures selectably on the display unit  30 , as illustrated in the lower part of  FIG. 3 . Therefore, the user can perform an operation of selecting any of the indices of the high-resolution partial pictures. 
     In step S 19 , on the basis of control information. acquired by the control-information acquisition unit  22  in accordance with a user operation detected by, the user-operation detection unit  21 , the mobile display device  13  detects an operation of determination as the display target to the index of a high-resolution partial picture. 
     In step S 20 , the reception-request generation unit   24  of the mobile display device  13  generates a viewing/listening request for distribution of the high-resolution partial picture determined by the user operation detected in step  819 . Then, the request transmission unit  25  of the mobile display device  13  transmits the viewing/listening request to the distribution server  15 . 
     In step S 21 , the picture reception unit  26  of the mobile display device  13  receives the high-resolution partial picture transmitted from the distribution server  15  in response to the viewing/listening request transmitted in step S 20 . Then, the display-picture generation unit  29  of the mobile display device  13  generates a display picture such that the high-resolution partial picture is adapted to the size of view and resolution of the display unit  30 , and then the display unit  30  displays the high-resolution partial picture. 
     In step S 822 , on the basis of control information acquired by the control-information acquisition unit  22  in accordance with a user operation detected by the user-operation detection unit  21 , the mobile display device  13  determines whether or not an operation of returning to the low-resolution entire picture has been performed. 
     In step S 22 , in a case where the mobile display device  13  determines that no operation of returning to the low-resolution entire picture has been performed, the processing goes back to step S 21 , so that the high-resolution partial picture remains displayed.  
     Meanwhile, in step S 22 , in a case where the mobile display device  13  determines that an operation of returning to the low-resolution entire picture has been performed, the processing goes back to step S 11 . After that, similar processing is repeatedly performed. 
     In the first content distribution processing as above, distribution control of content and display of a high-resolution partial picture are both performed in the mobile display device  13 . Then, through the user interface on which high-resolution areas are superimposition-displayed onto a low-resolution entire picture, the user performs an operation of enlargement-displaying a high-resolution area, so that the user can view and listen to a desired high-resolution partial picture due to a simple operation. 
     Second Content Distribution Processing 
     Second content distribution processing that is performed in the content distribution system  11  will be exemplarily described with reference to a flowchart illustrated in.  FIG. 9 . 
     In step S 31 , the distribution server  15  generates a low-resolution entire picture and high-resolution partial pictures and generates picture metadata regarding the high-resolution partial pictures. In this case, the picture metadata includes identifications (IDs) that rank the high-resolution partial pictures.  
     Processing similar to that in steps S 11  to S 14  of  FIG. 8  is performed in steps S 32  to S 35 . 
     Then, in step S 36 , on the basis of the picture metadata received by the picture-meta data reception unit  27  in step S 32 , the superimposition-data generation unit  28  of the mobile display device  13  generates, as superimposition data, respective indices of high-resolution partial pictures to be superimposed on the low-resolution entire picture. Moreover, the mobile display device  13  gives the indices the corresponding ranking IDs. The IDs are linked with the indices. 
     In step S 37 , the display-picture generation unit  29  of the mobile display device  13  generates a display picture in which the indices of the high-resolution partial pictures given the IDs based on the superimposition data generated by the superimposition-data generation unit  28  are superimposed on the low-resolution entire picture received by the picture reception unit  26 . Thus, the mobile display device  13  can display, on the display unit  30 , the low-resolution entire picture on which the indices of the high-resolution partial pictures given the IDs are superimposed. 
     In step S 38 , on the basis of a user operation detected by the user-operation detection unit  21 , the mobile display device  13  performs display such that the selection state between the indices of the high-resolution partial pictures transitions sequentially in  the order of the ranking IDs. 
     In step S 39 , in accordance with a user operation detected by the user-operation detection unit  21 , the mobile display device  13  determines whether or not an operation of determination as the display target has been performed to the index of a high-resolution partial picture having been selected. 
     In step S 39 , in a case where the mobile display device  13  determines that no operation of determination as the display target has been performed, the processing goes back to step S 32 . After that, similar processing is repeatedly performed. Meanwhile, in step  339 , in a case where the mobile display device  13  determines that an operation of determination as the display target has been performed, the processing proceeds to step S 40 . 
     After that, processing similar to that in steps  320  to  322  of  FIG. 8  is performed in steps  340  to S 42 . 
     In the second content distribution processing as above, distribution control of content and display of a high-resolution partial picture are both performed in the mobile display device  13 . Then, through the user interface on which the indices of high-resolution partial pictures are superimposition-displayed onto a low-resolution entire picture, the user performs operations of sequential selection pursuant to IDs and determination, so that the user can view and listen to a desired high-resolution partial picture due to a simple  operation. 
     Third Content Distribution Processing 
     Third content distribution processing that is performed in the content distribution system  11  will be described with reference to a flowchart illustrated in  FIG. 10 . 
     Processing similar to that in steps S 11  to S 14  of  FIG. 8  is performed in steps S 51  to S 54 . 
     Then, in step S 55 , on the basis of the picture metadata received by the picture-metadata reception unit  27  in step S 51 , the superimposition-data generation unit  28  of the mobile display device  13  generates, as superimposition data, respective thumbnail images of high-resolution partial pictures from a low-resolution entire picture. For example, the superimposition-data generation unit  28  extracts, from the low-resolution entire picture, the images corresponding to the locations at which the high-resolution partial pictures are present, and adjusts the sizes of the images to the sizes of thumbnail images, so that the thumbnail images can be generated. 
     In step S 56 , the display-picture generation unit  29  of the mobile display device  13  generates a display picture in which. the thumbnail images based on the superimposition data generated by the superimposition-data generation unit  26  are superimposed on the low-resolution entire picture received by the picture  reception unit  26 . 
     In step S 57 , the mobile display device  13  displays, on the display unit  30 , the low-resolution entire picture on which the thumbnail images are superimposed, as described with reference to  FIG. 4 . Therefore, in a case where the user desires to view and listen to a high-resolution partial picture among the thumbnail images, the user can perform an operation of selecting the thumbnail image of the high-resolution partial picture. 
     In step S 58 , in accordance with a user operation detected by the user-operation detection unit  21 , the mobile display device  13  determines whether or not an operation of determining, as the display target, a high-resolution partial picture has been performed to a thumbnail image. 
     In step S 58 , in a case where the mobile display device  13  determines that no operation of determination as the display target has been performed, the processing goes back to step S 51 . After that, similar processing is repeatedly performed. Meanwhile, in step S 58 , in a case where the mobile display device  13  determines that an operation of determination as the display target has been performed, the processing proceeds to step S 59 . 
     After that, processing similar to that in steps S 20  to S 22  of  FIG. 8  is performed in steps S 59  to S 61 . 
     In the third content distribution processing as  above, distribution control of content and display of a high-resolution partial picture are both performed in the mobile display device  13 . Then, through the user interface on which the thumbnail images of high-resolution partial pictures generated in the mobile display device  13  are superimposition-displayed onto a low-resolution entire picture, the user can view and listen to a desired high-resolution partial picture due to a simple operation. 
     Fourth Content Distribution Processing 
     Fourth content distribution processing that is performed in the content distribution system  11  will be exemplarily described with reference to a flowchart illustrated in  FIG. 11 . 
     In step S 71 , the distribution server  15  generates, in generation of a low-resolution entire picture and high-resolution partial pictures, respective thumbnail images of the high-resolution partial pictures. 
     In step S 72 , the picture reception unit  26  of the mobile display devices  13  receives the low-resolution entire picture transmitted from the distribution server  15 , and the picture-metadata reception unit  27  of the mobile display device  13  receives picture metadata transmitted from the distribution server  15 . Moreover, the picture-metadata reception unit  27  of the mobile display device  13  receives the thumbnail images of the high-resolution partial pictures transmitted from the distribution server  15 .  
     Processing similar to that in steps S 12  to S 14  of  FIG. 8  is performed in steps S 73  to S 75 . 
     Then, in step S 76 , the display-picture generation. unit  29  of the mobile display device  13  generates a display picture in which the thumbnail images of high-resolution partial pictures received by the picture-metadata reception unit  27  in step S 72  are superimposed on the low-resolution entire picture received by the picture reception unit  26 . 
     In step S 77 , the mobile display. device  13  displays, on the display unit  30 , the low-resolution entire picture on which the thumbnail images are superimposed, as described with reference to  FIG. 4 . Therefore, in a case where the user desires to view and listen to a high-resolution partial picture among the thumbnail images, the user can perform an operation of selecting the thumbnail image of the high-resolution partial picture. 
     In step S 78 , in accordance with a user operation detected by the user-operation detection unit  21 , the mobile display device  13  determines whether or not an operation of determining, as the display target, a high-resolution partial picture has been performed to a thumbnail image. 
     In step S 78 , in a case where the mobile display device  13  determines that no operation of determination as the display target has been performed, the processing  goes back to step S 72 . After that, similar processing is repeatedly performed. Meanwhile, in step S 78 , in a case where the mobile display device  13  determines that an operation of determination as the display target has been performed, the processing proceeds to step S 79 . 
     After that, processing similar to that in steps S 20  to S 22  of  FIG. 8  is performed in step S 79  to S 81 . 
     In the fourth content distribution processing as above, distribution control of content and display of a high-resolution partial picture are both performed in the mobile display device  13 . Then, through the user interface on which the thumbnail images of high-resolution partial pictures generated in the distribution server  15  are superimposition-displayed on a low-resolution entire picture, the user can view and listen to a desired high-resolution partial picture due to a simple operation. 
     Fifth Content Distribution Processing 
     Fifth content distribution processing that is performed in the content distribution system  11  will be exemplarily described with reference to a flowchart illustrated in  FIG. 12 . 
     In step S 91 , the distribution server  15  generates, in generation of a low-resolution entire picture and high-resolution partial pictures, respective thumbnail images of the high-resolution partial pictures.  
     In step S 92 , the distribution server  15  generates one combined picture in which the thumbnail images of the high-resolution partial pictures are superimposed on proper locations on the low-resolution entire picture (hereinafter, referred to as a thumbnail-superimposed picture). 
     In step S 93 , the picture reception unit  26  of the mobile display device  13  receives the thumbnail-superimposed picture transmitted from the distribution server  15 , and the picture-metadata reception unit  27  of the mobile display device  13  receives picture metadata transmitted from the distribution server  15 . 
     In step S 94 , the display-picture generation unit  29  of the mobile display device  13  generates a display picture such that the thumbnail-superimposed picture received by the picture reception unit  26  in step S 93  is adapted to the size of view and resolution of the display unit  30 . Then, the mobile display device  13  displays the thumbnail-superimposed picture on the display unit  30 . 
     In step S 95 , in accordance with a user operation detected by the user-operation detection unit  21 , the mobile display device  13  determines whether or not an operation of determining, as the display target, a high-resolution partial picture has been performed to a thumbnail image. 
     In step S 95 , in a case where the mobile display device  13  determines that no operation of determination  as the display target has been performed, the processing goes back to step S 94 , so that the thumbnail-superimposed picture remains displayed. Meanwhile, in step S 95 , in a case where the mobile display device  13  determines that an operation of determination as the display target has been performed, the processing proceeds to step S 96 . 
     In step S 96 , the mobile display device  13  specifies the display place of the thumbnail image determined as the display target, and the reception-request generation unit  24  generates a viewing/listening request for distribution of the high-resolution partial picture corresponding to the thumbnail image. Then, the request transmission unit  25  of the mobile display device  13  transmits the viewing/listening request to the distribution server  15 . 
     After that, processing similar to that in steps S 21  and S 22  of  FIG. 8  is performed in steps S 97  and S 98 . 
     In the fifth content distribution processing as above, distribution control of content and display of a high-resolution partial picture are both performed in the mobile display device  13 . Then, through the user interface on which a thumbnail-superimposed picture generated in the distribution server  15  is displayed, the user can view and listen to a desired high-resolution partial picture due to a simple operation. 
     Modifications in Case Where No High-Resolution Partial Pictures Are Present  
     For example, in a case where it is determined that no high-resolution partial pictures are present in step S 13  of  FIG. 8  described above, the low resolution entire picture is displayed in step S 14 . In contrast to this, in a case where no high-resolution partial pictures are present, instead of the processing in step S 14 , processing of requesting generation of a high-resolution partial picture can be performed. Furthermore, in step S 35  of  FIG. 9 , step S 54  of  FIG. 10 , and step S 75  of  FIG. 11 , similarly, processing of requesting generation of a high-resolution partial picture can be performed. 
       FIG. 13  is an explanatory flowchart of processing of requesting generation of a high-resolution partial picture in a case where no high-resolution partial pictures are present. 
     For example, in a case where it is determined that no high-resolution partial pictures are present in step S 13  of  FIG. 8 , the processing starts. In step S 111 , the mobile display device  13  specifies an area the user desires to view and listen to as a high-resolution partial picture in the display of the low-resolution entire picture. 
     In step S 112 , with reference to the picture metadata of content being reproduced, the mobile display device  13  determines whether or not a high-resolution partial picture can be generated for the area the user desires to view and listen to as a high-resolution partial picture.  
     In step S 112 , in a case where the mobile display device  13  determines that a high-resolution partial picture can be generated for the area the user desires to view and listen to as a high-resolution partial picture, the processing proceeds to step S 113 . 
     In step S 113 , on the basis of information regarding the area the user desires to view and listen to as a high-resolution partial picture, the reception-request generation unit  24  of the mobile display device  13  generates a viewing/listening request for generation and distribution of the high-resolution partial picture. Then, the request transmission unit  25  of the mobile display device  13  transmits the viewing/listening request to the distribution server  15 . 
     The distribution server  15  generates the high-resolution partial picture on the basis of the viewing/listening request, and transmits the high-resolution partial picture to the mobile display device  13 . 
     In step S 114 , the picture reception unit  26  of the mobile display device  13  receives the high-resolution partial picture generated by the distribution server  15 . Then, the display-picture generation unit  29  of the mobile display device  13  generates a display picture such that the high-resolution partial picture is adapted to the size of view and resolution of the display unit  30 , and then the display unit  30  displays the high-resolution  partial picture. 
     Meanwhile, in step S 112 , in a case where the mobile display device  13  determines that no high-resolution partial picture can be generated for the area the user desires to view and listen to as a high-resolution partial picture, the processing proceeds to step S 115 . 
     In step S 115 , the mobile display device  13  extracts, from the low-resolution entire picture, the part corresponding to the area the user desires to view and listen to as a high-resolution partial picture, and the display-picture generation unit  29  Generates a display picture such that the part is enlarged. 
     In step S 116 , the mobile display device  13  displays, on the display unit  30 , the display picture generated in step S 115 . 
     After the processing in step S 114  or S 116 , for example, the processing proceeds to step S 22  of  FIG. 8 . Then, it is determined whether or not an operation of returning to the low-resolution entire picture has been performed. After that, similar processing is repeatedly performed. 
     In the processing as above, even in a case where an area where no high-resolution partial picture is present is selected, the mobile display device  13  requests generation of a high-resolution partial picture or enlarges the low-resolution entire picture, so that the  content can remain reproduced. 
     Sixth Content Distribution Processing 
     As described above with reference to  FIG. 1 , in the content distribution system  11 , in a case where distribution control of content and display of a high-resolution partial picture are performed by different pieces of equipment, an operation of selecting a high-resolution partial picture is performed in the mobile display device  13 , and the large-screen display device  14  displays the high-resolution partial picture. 
     Sixth content distribution processing that is performed in the content distribution system  11 , namely, processing in which distribution control of content and display of a high-resolution partial picture are performed by different pieces of equipment, will be exemplarily described with reference to a flowchart illustrated in  FIG. 14 . 
     In step S 121 , the size of view and resolution of the large-screen display device  14  are set to the mobile display device  13 . 
     In step S 122 , the picture reception unit  26  of the mobile display device  13  receives a low-resolution entire picture transmitted from the distribution server  15 , and the picture-metadata reception unit  27  of the mobile display device  13  receives picture metadata transmitted from the distribution server  15 .  
     In step S 123 , the control-information analysis unit  23  of the mobile display device  13  analyzes the picture metadata received by the picture-metadata reception unit  27  in step S 122 . 
     In step S 124 , in accordance with an analytical result from the control-information analysis unit  23  in step S 123 , the mobile display device  13  determines whether or not any high-resolution partial pictures adaptable to the size of view and resolution of the large-screen display device  14  are present. 
     In step S 124 , in a case where the mobile display device  13  determines that no high-resolution partial pictures adaptable to the size of view and resolution of the large-screen display device  14  are present, the processing goes back to step S 112 . After that, similar processing is repeatedly performed. 
     Meanwhile, in step, S 124 , in a case where the mobile display device  13  determines that high-resolution partial pictures adaptable to the size of view and resolution of the large-screen display device  14  are present, the processing proceeds to step S 125 . 
     In step S 125 , the superimposition-data generation unit  28  of the mobile display device  13  generates, as superimposition data, respective indices of the high-resolution partial pictures to be superimposed onto the locations where the high-resolution partial pictures are present in the low-resolution entire picture.  
     In step S 126 , the mobile display device  13  displays, on the display unit  30 , the low-resolution entire picture on which the indices of the high-resolution partial pictures are superimposed. 
     In step S 127 , in accordance with a user operation detected by the user-operation detection unit  21 , the mobile display device  13  determines whether or not an operation of determination as the display target has been performed to the index of a high-resolution partial picture having been selected. 
     In step S 127 , in a case where the mobile display device  13  determines that no operation of determination as the display target has been performed, the processing goes back to step S 122 . After that, similar processing is repeatedly performed. Meanwhile, in step S 127 , in a case where the mobile display device  13  determines that an operation of determination as the display target has been performed, the processing proceeds to step S 128 . 
     In step S 128 , the mobile display device  13  transmits, to the large-screen display device  14 , the uniform resource locator (URL) and index information of the high-resolution picture determined as the display target. 
     In step S 129 , on the basis of the URL and index information of the high-resolution partial picture, the large-screen display device  14  transmits, to the  distribution server  15 , a viewing/listening request for distribution of the high-resolution partial picture. 
     In step S 130 , the large-screen display&#39; device  14  receives and displays the high-resolution partial picture transmitted from the distribution server  15  in response to the viewing/listening request transmitted in step S 129 . 
     In step S 131 , on the basis of control information. 
     acquired by the control-information acquisition unit  22  in accordance with a user operation detected by the user-operation detection unit  21 , the mobile display device  13  determines whether or not an operation of returning to the low-resolution entire picture has been performed. 
     In step S 131 , in a case where the mobile display device  13  determines that an operation of returning to the low-resolution entire picture has been performed, the processing goes back to step S 122 . After that, similar processing is repeatedly performed. 
     Meanwhile, in step S 131 , in a case where the mobile display device  13  determines that no operation of returning to the low-resolution entire picture has been performed, the processing proceeds to step S 132 . 
     In step S 132 , the mobile display device  13  determines whether or not to display, on the display unit  30 , a high-resolution partial picture identical to the high-resolution partial picture displayed on the large-screen display device  14 . 
     In step S 132 , in a case where the mobile display device  13  determines not to display an identical picture on the display unit  30 , the processing goes back to step 
     S 122 , and the High-resolution partial picture remains displayed. 
     Meanwhile, in step S 132 , is a case where the mobile display device  13  determines to display an identical picture on the display unit  30 , the processing proceeds to step S 133 . 
     In step S 133 , the request transmission unit  25  of the mobile display device  13  transmits, to the distribution server  15 , a viewing/listening request identical to that transmitted by the large-screen display device  14 . 
     In step S 134 , the picture reception unit  26  of the mobile display device  13  receives the high-resolution partial picture transmitted from the distribution server  15  in response to the viewing/listening request transmitted in step S 133 , and then the display unit  30  displays the high-resolution partial picture. 
     After the processing in step S 134 , the processing goes back to step S 132 . After that, similar processing is repeatedly performed. 
     In the sixth content distribution processing as  above, the mobile display device  13  performs distribution control of content, and the large-screen display device  14  performs display of a high-resolution partial picture. Thus, the user can view and listen to a desired high-resolution partial picture displayed on the large-screen display device  14  due to a simple operation. 
     Second Exemplary Configuration of Content Distribution System 
       FIG. 15  is a block diagram of an exemplary configuration of a content distribution system according to a second embodiment to which the present technology is applied. Note that constituents in the content distribution system  11 A illustrated in  FIG. 15  resembling those in the content distribution system  11  of  FIG. 1  are denoted with the same reference signs, and the detailed descriptions thereof will be omitted. 
     As illustrated in  FIG. 15 , the content distribution system  11 A resembles the content distribution system  11  of  FIG. 1  in that a distribution server  15  is connected to a network  12  and the distribution server  15  is connected with a content storage unit  16 . Meanwhile, the content distribution system  11 A is different from the content distribution system  11  of  FIG. 1  in that a large-screen display device  14 A is connected to the network  12  and a user performs, with a remote controller  17 , an operation to content. 
     The large-screen display device  14 A is, for example, a large-size display device capable of  displaying a high-definition picture. The large-screen display device  14 A is capable of performing communication with the distribution server  15  through the network  12 . 
     The remote controller  17  is equipment for operation to content that the large-screen display device  14 A reproduces. As the remote controller  17 , a remote controller for a general television receiver can be used. 
     In the content distribution system  11 A having such a configuration, in a case where a picture reproduction system built in the large-screen display device  14 A recognizes that a picture to be reproduced is an entire celestial sphere, an operation guide enabling spatial control of the picture is displayed on the screen of the large-screen display device  14 A. Then, functions for control and display of the spatial direction of the picture are allocated to buttons of the remote controller  17 . This arrangement enables the user to operate the remote controller  17  such that temporal control or temporal and spatial control is performed to content that the large-screen display device  14 A reproduces. 
     Exemplary Operations to Content 
     Exemplary operations to content with the remote controller  17  will be described with reference to  FIGS. 16 to 20 . 
       FIG. 16  illustrates a first exemplary operation of automatic movement of the line-of-sight to a low-resolution entire picture with a specific button kept  pressed down. 
     As illustrated in  FIG. 16 , an operation guide with an entire-celestial-spherical model is displayed on the screen of the large-screen display device  14 A. The message “the present content is an entire-celestial-spherical moving image. The point of view is automatically being moved” is displayed. Then, the locus of automatic movement of the point of view (solid-white arrows) is displayed and the current location of the point of view (black triangle) is displayed on the entire-celestial-spherical model displayed as the operation guide. 
     For example, a function of moving the point of view in accordance with a specific locus of an entire-celestial-spherical picture with a button kept pressed down and stopping the point of view with the button released, is allocated to a specific button of the remote controller  17  (button enclosed with a thick broken line in the example of  FIG. 16 ). 
       FIG. 17  illustrates a second exemplary operation of arbitrary movement of the line-of-sight to a low-resolution entire picture with a button for specifying a direction. 
     As illustrated in  FIG. 17 , an operation guide indicating a method of operating an arrowed button is displayed on the screen of the large-screen display device  14 A. The message “the present content is an  entire-celestial-spherical moving image. Use of the arrowed button for up, down, left, and right enables movement of the point of view” is displayed. 
     For example, a function of moving the point of view up, down, left, and right is allocated to the arrowed button for up, down, left, and right of the remote controller  17  enclosed with a thick broken line. Furthermore, a function of moving the point of view to the home position is allocated to the enter button arranged at the center of the arrowed button for up, down, left, and right of the remote controller  17 . 
       FIG. 18  illustrates a third exemplary operation of enlargement of a predetermined place in a low-resolution entire picture with buttons for specifying numbers. 
     As illustrated in  FIG. 18 , an operation guide ndicating directions in which movement can be made with numbers (1 and 2 in the example of  FIG. 18 ) is displayed on the screen of the large-screen display device  14 A. The message “the present content is an entire-celestial-spherical moving image. Use of a numeric button enables enlargement of the corresponding part” is displayed. 
     For example, a function of enlargement-displaying respective locations associated with numeric buttons is allocated to the numeric buttons of the remote controller  17  enclosed with a thick broken line. That is pressing the numeric button for 1 down causes movement of the point of view to “1” in the operation guide displayed on  the screen of the large-screen display device  14 A resulting in enlargement and display, and pressing the numeric button for 2 down causes movement of the point of view to “2” in the operation guide displayed on the screen of the large-screen display device  14 A, resulting in enlargement and display. 
     Exemplary allocation of functions to existing buttons arranged in the remote controller  17  will be described with reference to  FIG. 19 . 
     For example, as described with reference to  FIG. 18 , a function of moving the point of view to a number in the operation guide displayed on the large-screen display device  14 A, is allocated to the numeric buttons of the remote controller  17 . 
     Furthermore, as described with reference to  FIG. 16 , a function of automatically moving the point of view along the locus on the entire-celestial-spherical model, is allocated to a specific button of the remote controller  17 . 
     Furthermore, a function of randomly moving the point of view in accordance with points in space previously set to a picture or the like or specific movement information, is allocated to the enter button or arrowed button for left and right of the remote controller  17 . 
     Furthermore, a function of redirecting the point of  view to the home position previously set to a picture, is allocated to the home-menu button of the remote controller  17 . 
     Furthermore, a function of zooming a picture in and out (enlargement with the + button and reduction with the − button) is allocated to the channel button of the remote controller  17 . 
     In addition, a function of displaying respective indices or thumbnails of high-resolution partial pictures, is allocated to a specific button of the remote controller  17  (e.g., an index button). Thus, a high-resolution partial picture can be selected with the up-down-left-right button, and the high-resolution partial picture can be displayed with the enter button. Alternatively, any points to which movement can be made are displayed on a picture displayed by the equirectangular projection, and use of a specific button of the remote controller  17  enables selection of a desired point. 
       FIG. 20  illustrates exemplary operation units for spatial control that are each installable in the remote controller  17 . 
     As illustrated in A of  FIG. 20 , an index button, a move button, arrowed buttons for 8 directions, a home button, a plus button, and a minus button can be installed as buttons for spatial control in the remote controller  17 .  
     As illustrated in B of  FIG. 20 , an index button, a move button, a home button, and a touch pad can be installed as buttons for spatial control in the remote controller  17 . 
     Exemplary Configuration of Large-Screen Display Device 
       FIG. 21  is a block diagram of an exemplary configuration of the large-screen display device  14 A. 
     As illustrated in  FIG. 21 , the large-screen display device  14 A includes a control-information reception unit  41 , a voice recognition unit  42 , a control-information analysis unit  43 , a picture-mode retention unit  44 , a spatial control unit  45 , a temporal control unit  46 , a reception-request generation unit  47 , a request transmission unit  48 , a picture reception unit  49 , a picture-metadata reception unit  50 , a picture-feature discrimination unit  51 , a superimposition-data generation unit  52 , a display-picture generation unit  53 , and a display unit  54 . 
     The control-information reception unit  41  receives control information transmitted from the remote controller  17  in accordance with an operation from the user to the remote controller  17 . For example, the control-information reception unit  41  receives control information regarding input of an operation of moving the point of view on a low-resolution entire picture to the remote controller  17  and control of display of a high-resolution partial picture. 
     For example, the voice recognition unit  42  performs voice recognition processing to a voice converted to an electric signal by a microphone not illustrated, to acquire control information based on the utterance of the user. For example, the voice recognition unit  42  recognizes voice causing input of an operation of moving the point of view on a low-resolution entire picture and control of display of a high-resolution partial picture. 
     The control-information analysis unit  43  analyzes, for example, the control information received by the control-information reception unit  41  or the control information acquired by the voice recognition processing of the voice recognition unit  42 . 
     The picture-mode retention unit  44  retains whether the picture mode of the large-screen display device  14 A is a temporal control mode or a temporal and spatial control mode. 
     On the basis of the control information analyzed by the control-information analysis unit  43 , the spatial control unit  45  controls the space of content that the large-screen display device  14 A reproduces. 
     On the basis of the control information analyzed by the control-information analysis unit  43 , the temporal control unit  46  controls the time of content that the large-screen display device  14 A reproduces.  
     The reception-request generation unit  47  generates a viewing/listening request for distribution of a resolution partial picture pursuant to the control of the spatial control unit.  45 . 
     The request transmission unit  48  transmits the viewing/listening request generated by the reception-request generation unit  47  to the distribution server  15  through the network  12 . 
     The picture reception unit  49  receives a low resolution entire picture or a high-resolution partial picture transmitted from the distribution server  15  through the network  12 , and then supplies the low-resolution entire picture or the high-resolution partial picture to the display picture generation unit  29 . 
     The picture-metadata reception unit  50  receives picture metadata transmitted from the distribution server  15  through the network  12 , and then supplies the picture metadata to the picture-feature discrimination unit  51 . 
     On the basis of the picture metadata received by the picture-metadata reception unit  50 , the picture-feature discrimination unit  51  discriminates the picture feature of content to be distributed. 
     On the basis of the picture metadata received by the picture-metadata reception unit  50 , the superimposition-data generation unit  52  generates  superimposition data to be superimposed onto the low-resolution entire picture received by the picture reception unit  49 . 
     The display-picture generation unit  53  generates a display picture in which the low-resolution entire picture or the high-resolution partial picture received by the picture reception unit  49  is adapted to the size of view and resolution of the display unit  54 , and then the display unit  54  displays the display picture. Furthermore, on the basis of the superimposition data generated by the superimposition-data generation unit  52 , the display-picture generation unit  53  generates, for example, a display picture in which high-resolution areas are superimposed on the low-resolution entire picture, a display picture in which respective indices of high-resolution partial pictures are superimposed on the low-resolution entire picture, a display picture in which respective thumbnail images of high-resolution partial pictures are superimposed on the low-resolution entire picture, or the like. Moreover, the display-picture generation unit  53  performs picture reproduction pursuant to the temporal control of the temporal control unit  46  (e.g., fast-forward/fast-reverse/pause/stop), and performs picture reproduction pursuant to the spatial control of the spatial control unit  45  (e.g., movement of the point of view/zooming). 
     The display unit  54  is, for example, a large-screen display, and displays the display picture generated by the display-picture generation unit  29 .  
     In the large-screen display device  14 A having such a configuration, for example, an operation of changing the orientation of the picture being viewed and listened to is performed by a voice specifying a direction (left, right, up, or down) following “more” or “by an angle of oo” or a voice specifying a latitude or longitude on the entire-celestial-spherical model. Furthermore, a voice specifying the index of a high-resolution partial picture may cause display of the high-resolution partial picture corresponding to the index. For example, a voice causes recognition of an index number, the voice “next” in order from the first index causes sequential display of high-resolution partial pictures, or the voice “the o-th” causes display of the high-resolution partial picture of the corresponding index. Furthermore, when an index is specified, the high-resolution partial picture as the display target can be determined by the voice “done”, and the high-resolution partial picture can be displayed by the voice “view and listen to”. 
     Seventh Content Distribution Processing 
     Seventh content distribution processing that is performed in the content distribution system  11 A will be exemplarily described with reference to a flowchart illustrated in  FIG. 22 . 
     In step S 141 , the picture-metadata reception unit  50  receives picture metadata transmitted from the distribution server  15 .  
     In step S 142 , on the basis of the picture metadata. received by the picture-metadata reception unit  50  in step S 141 , the picture-feature discrimination unit  51  determines whether or not spatial control of content to be distributed can be performed. 
     In step S 142 , in a case where the picture-feature discrimination unit  51  determines that spatial control of content to be distributed can be performed, the processing proceeds to step S 143 , so that the picture mode is determined to transition to the temporal and spatial control mode. 
     Meanwhile, in step S 142 , in a case where the picture-feature discrimination unit  51  determines that no spatial control of content to be distributed can be performed, the processing proceeds to step S 144 , so that the picture mode is determined to transition to the temporal control mode. 
     After the processing in step S 143  or S 144 , the processing proceeds to step S 145 , and the picture-feature discrimination unit  51  sets the picture mode retained in the picture-mode retention unit  44 . That is, in a case where the picture mode is determined to transition to the temporal and spatial control mode in step S 143 , the picture mode retained in the picture-mode retention unit  44  is set to the temporal and spatial control mode. Similarly, in a case where the picture mode is determined to transition to the temporal control mode in step S 144 , the picture mode retained in the picture-mode retention  unit  44  is set to the temporal control mode. 
     In step S 146 , on the basis of the picture metadata received by the picture-metadata reception unit  50  in step S 141 , the superimposition-data generation unit  52  creates such an operation guide as illustrated in  FIGS. 16 to 18  and generates thumbnails. 
     In step S 147 , the display unit  54  displays the operation guide generated by the superimposition-data generation unit  52  in step S 146 . 
     In step S 148 , the control-information reception unit  41  stands by for reception of control information that the remote controller  17  transmits. Note that, in a case where an operation is performed by voice, the voice recognition unit  42  stands by for input of voice. 
     In step S 149 , the control-information reception unit  41  determines whether or not the control information transmitted from the remote controller  17  in accordance with an operation from the user to the remote controller  17  has been received. In step S 149 , in a case where the control-information reception unit  41  determines that no control information has been received, the processing stands by. Meanwhile, in a case where it is determined that the control information has been received, the processing proceeds to step S 150 . 
     In step S 150 , the control-information analysis unit  43  determines whether the picture mode retained in the  picture-mode retention unit  44  is the temporal control mode or the temporal and spatial control mode. 
     In step S 150 , in a case where the control-information analysis unit  43  determines that the picture mode retained in the picture-mode retention unit  44  is the temporal control mode, the processing proceeds to step S 151 . In step S 151 , the temporal control unit  46  performs temporal control of the picture (e.g., fast-forward/fast-reverse/pause/stop). 
     Meanwhile, in step S 150 , in a case where the control-information analysis unit  43  determines that the picture mode retained in the picture-mode retention unit  44  is the temporal and spatial control mode, the processing proceeds to step S 152 . 
     In step S 152 , the control-information analysis unit  43  determines whether an operation signal received by the control-information reception unit  41  indicates temporal control or spatial control. In step S 152 , in a case where the control-information analysis unit  43  determines that the operation signal indicates temporal control, the processing proceeds to step S 151 , and then processing similar to that described above is performed. 
     Meanwhile, in step S 152 , in a case where the control-information analysis unit  43  determines that the operation signal indicates spatial control, the processing proceeds to step S 153 . In step S 153 , the spatial control unit  45  determines whether or not any  different divided file is required. 
     In step S 153 , in a case where the spatial control unit  45  determines that no different divided file is required, the processing proceeds to step S 154 . In step S 154 , the spatial control unit  45  performs spatial control of the picture (e.g., movement of the point of view zooming). 
     Meanwhile, in step S 153 , in a case where the spatial control unit  45  determines that a different divided file is required, the processing proceeds to step S 155 . In step S 155 , the reception-request generation unit  47  generates a viewing/listening request for distribution of the different divided file that the spatial control unit  45  requires. 
     In step S 156 , the request transmission unit  48  transmits the viewing/listening request generated by the reception-request generation unit  47  in step S 155 , to the distribution server  15  through the network  12 . 
     In step S 157 , the picture reception unit  49  receives a high-resolution partial picture transmitted from the distribution server  15  through the network  12  in response to the viewing/listening request transmitted in step S 156 . 
     After the processing in step S 151 , S 154 , or S 157 , the processing proceeds to step S 158 . Then, the display-picture generation unit  53  reproduces the picture, and  the display unit  54  displays the picture. After that, the processing goes back to step S 148 . After that, similar processing is repeatedly performed. 
     As above, in the large-screen display device  14 A, the user can change the picture in orientation or zoom the picture, for example, without stress by an operation through the remote controller  17  or voice recognition of the voice recognition unit  42 , so that the user can easily access a high-resolution partial picture. 
     Then, in each of the content distribution systems  11  and  11 A, for high-resolution partial pictures prepared by hierarchically division technology, the corresponding locations on an entire-celestial-spherical low-resolution entire picture and the respective features of the high-resolution pictures are displayed, so that the user can grasp the presence of viewable and audible high-resolution pictures and can view and listen to the high-resolution. pictures. 
     Exemplary Configuration of Computer 
     Next, each flow of processing described above (display control method) can be performed by hardware or software. In a case where each flow of processing is performed by software, a program included in the software is installed on, for example, a general-purpose computer. 
       FIG. 23  is a block diagram of an exemplary configuration of a computer according to an embodiment on which a program for performing any of the flows of  processing described above is installed. 
     The program can be previously recorded on a hard disk  105  or a ROM  103  as a recording medium built in the computer. 
     Alternatively, the program can be stored (recorded) in a removable recording medium  111  that a drive  109  drives. The removable recording medium  111  can be provided as so-called packaged software. Here, examples of the removable recording medium  111  include a flexible disk, a compact disc read only memory (CD-ROM), a magneto optical (MO) disc, a digital versatile disc (DVD), a magnetic disk, a semiconductor memory, and the like. 
     Note that the program not only can be installed from the removable recording medium  111  described above onto the computer, but also can be installed on the built-in hard disk  105  by download to the computer through a communication network or a broadcast network. That is, for example, the program can be transferred from a download site to the computer by wireless through an artificial satellite for digital satellite broadcasting or by wire through a network, such as a local area network (LAN) or the Internet. 
     The computer includes a central processing unit (CPU)  102  built therein, and the CPU  102  is connected with an input/output interface  110  through a bus  101 . 
     For example, when a user operates an input unit  107   to input a command through the input/output interface  110 , in accordance with the command, the CPU  102  executes the program stored in the read only memory (ROM)  103 . Alternatively, the CPU  102  loads the program stored in the hard disk  105  into a random access memory (RAM)  104  and executes the program. 
     This arrangement causes the CPU  102  to perform the processing corresponding to any of the flowcharts described above or the processing in the configuration in any of the block diagrams described above. Then, for example, as necessary, through the input/output interface  110 , the CPU  102  causes an output unit  106  to output a result of the processing or a communication unit  108  to transmit the result of the processing, and moreover records the result of the processing on the hard disk  105 . 
     Note that the input unit  107  includes, for example, a keyboard, a mouse, and a microphone. Furthermore, the output unit  106  includes, for example, a liquid crystal display (LCD) and a speaker. 
     Here, in the present specification, the processing that the computer performs in accordance with the program, is not necessarily performed on a time-series basis in the order described in the corresponding flowchart. That is the processing that the computer performs in accordance with the program includes processing to be performed parallel or individually (e.g., parallel processing or processing with object).  
     Furthermore, the program may be subjected to processing by one computer (processor) or may be subjected to decentralized processing by a plurality of computers. Moreover, the program may be transferred to a remote computer so as to be executed. 
     Moreover, in the present specification, the system means an aggregate of a plurality of constituent elements (e.g., devices and modules (components)) regardless of whether or not all the constituent elements are included in the same housing. Therefore, a plurality of devices connected through a network, the devices each being housed in a different housing, and one device including a plurality of modules housed in one housing, are involved all in the system. 
     Furthermore, for example, a configuration described as one device (or one processing unit) may be divided to form a plurality of devices (or processing units). Conversely, configurations described above as a plurality. of devices (or processing units) may be integrated to form one device (or one processing unit). Furthermore, the configuration of each device (or each processing unit) may be given a configuration other than the configurations described above. Moreover, as long as the configuration or operation of the entire system remains substantially the same, the configuration of a device (or a processing unit) may be partially included in the configuration of a different device (or a different processing unit).  
     Furthermore, for example, the present technology can have the configuration of cloud computing in which a plurality of devices dividedly processes one function in cooperation through a network. 
     Furthermore, for example, the program described above can be executed by an arbitrary device. In that case, the device is only required to have necessary functions (e.g., functional blocks) and to be capable of acquiring necessary information. 
     Furthermore, for example, each step in each flowchart described above can be performed by one device or can be dividedly performed by a plurality of devices. Moreover, in a case where one step includes a plurality of pieces of processing, the plurality of pieces of processing included in the one step can be performed by one device or can be dividedly performed by plurality of devices. In other words, a plurality of pieces of processing included in one step can be performed as the processing in a plurality of steps. Conversely, processing described as a plurality of steps can be collectively performed as one step. 
     Note that, regarding the program that the computer executes, the processing in the steps describing the program may be performed on a time-series basis in the order described in the present specification or may be performed in parallel or individually with necessary timing, such as a call. That is, as long as no  inconsistency occurs, the processing in each step may be performed in order different from the order described above. Moreover, the processing in the steps describing the program may be performed in parallel with the processing of a different program or may be performed in combination with the processing of a different program. 
     Note that each of the plurality of configurations according to the present technology described in the present specification can be achieved independently and individually as long as no inconsistency occurs. Needless to say, any plurality of configurations according to the present technology can be achieved together. For example, the entirety or part of any of the embodiments according to the present technology can be achieved in combination with the entirety or part of another embodiment according to the present technology. Furthermore, any part or all according to the present technology described above can be achieved together with another technology not described above. 
     Exemplary Combinations of Configurations 
     Note that the present technology can have the following configurations. 
     (1) 
     A display control device including: 
     a superimposition-data generation unit configured to generate, in reproduction of content hierarchically including a plurality of high-definition partial pictures and a low-resolution entire picture including the plurality of partial pictures as regions, superimposition  data to be superimposed onto the entire picture, on the basis of metadata regarding the partial pictures; 
     a display-picture generation unit configured to generate a display picture in which a picture based on the superimposition data is superimposed on the entire picture; and 
     a request transmission unit configured to transmit a request for distribution of a desired partial picture selected from the partial pictures with the display picture. 
     (2) 
     The display control device according to (1) above, in which 
     the superimposition-data generation unit generates, as the superimposition data, a high-resolution area such that areas in which the partial pictures are present are enclosed on the entire picture. 
     (3) 
     The display control device according to (1) above, in which 
     the superimposition-data generation unit generates, as the superimposition data, indices of the partial pictures. 
     (4) 
     The display control device according to (3) above, in which 
     the metadata includes IDs that are linked with the indices and rank the partial pictures. 
     (5) 
     The display control device according to (1) above, in which  the superimposition-data generation unit generates, as the superimposition data, thumbnail images of the partial pictures. 
     (6) 
     The display control device according to (5) above, in which 
     the thumbnail images are generated either in a reproduction device that reproduces the content or in a distribution device that distributes the content. 
     (7) 
     The display control device according to (1) above, in which 
     a thumbnail-superimposed picture in which thumbnail images of the partial pictures are superimposed on the entire picture is generated so as to be distributed in a distribution device that distributes the content, and 
     the request transmission unit transmit, in accordance with a location specified on the thumbnail superimposed picture, the request for the partial picture arranged at the location. 
     (8) 
     The display control device according to (1) above, in which 
     in a case where the desired partial picture is specified for viewing and listening in a display of the entire picture and the desired partial picture is not present in a reproduction device that reproduces the content, the request transmission unit transmits the request for generation of the desired partial picture for distribution in the reproduction device that reproduces the content.  
     (9) 
     The display control device according to any of (1) to (8) above, in which 
     a first display device that displays the display picture generated by the display-picture generation unit and controls the selection of the desired partial picture as a display target, is different from a second display device that displays the desired partial picture transmitted in response to the request. 
     (10) 
     The display control device according to any of (1) to (9) above, further including: 
     a control unit configured to control display in accordance with control information from a control device including a plurality of buttons for input of an operation or moving a point of view on the entire picture and control of display of the desired partial picture. 
     (11) 
     The display control device according to any of (1) to (10) above, further including: 
     a voice recognition unit configured to recognize voice causing input of an operation of moving a point of view on the entire picture and control of display of the desired partial picture, in which 
     the control unite, controls display in accordance with a recognition result from the voice recognition unit. 
     (12) 
     A display control method including: 
     generating, in reproduction of content hierarchically including a plurality of high-definition  partial pictures and a low-resolution entire picture including the plurality of partial pictures as regions, superimposition data to be superimposed onto the entire picture, on the basis of metadata regarding the partial pictures; 
     generating a display picture in which a picture based on the superimposition data is superimposed on the entire picture; and 
     transmitting a request for distribution of a desired partial picture selected from the partial pictures with the display picture. 
     (13) 
     A program for causing a computer of a display control device that performs display control, to perform. processing including: 
     generating, in reproduction of content hierarchically including a plurality of high-definition partial pictures and a low-resolution entire picture including the plurality of partial pictures as regions, superimposition data to be superimposed onto the entire picture, on the basis of metadata regarding the partial pictures; 
     generating a display picture in which a picture based on the superimposition data is superimposed on the entire picture; and 
     transmitting a request for distribution of a desired partial picture selected from the partial pictures with the display picture. 
     Note that the present embodiment is not limited to the embodiments described above, and thus various  alterations may be made without departing from the scope of the gist of the present disclosure. Furthermore, the effects described in the present specification are just exemplary and are not limitative, and thus other effects may be provided. 
     REFERENCE SIGNS LIST 
       11  Content distribution system 
       12  Network 
       13  Mobile display device 
       14  Large-screen display device 
       15  Distribution server 
       16  Content storage unit 
       17  Remote controller 
       21  User-operation detection unit 
       22  Control-information acquisition unit 
       23  Control-information analysis unit 
       24  Reception-request generation unit 
       25  Request transmission unit 
       26  Picture reception unit 
       27  Picture-metadata reception unit 
       28  Superimposition-data generation unit 
       29  Display-picture generation unit 
       30  Display unit 
       41  Control-information reception unit 
       42  Voice recognition unit 
       43  Control-information analysis unit 
       44  Picture-mode retention unit 
       45  Spatial control unit 
       46  Temporal control unit  
       47  Reception-request generation unit 
       48  Request transmission unit 
       49  Picture reception unit 
       50  Picture-metadata reception unit 
       51  Picture-feature discrimination unit 
       52  Superimposing-data generation unit 
       53  Display-picture generation unit 
       54  Display unit