Abstract:
When display of an image that is sent from a portable terminal ( 101 ) for a portable screen is divided into screens for two vehicle mounted terminals, an image receiving unit A ( 21 ) of a vehicle mounted terminal A ( 102 ) receives image data necessary for screen display on both the vehicle mounted terminals from the portable terminal ( 101 ) and stores image data necessary for a vehicle mounted terminal B ( 103 ) in a huller memory unit ( 23 ). Thereafter, a cut-out processing unit ( 25 ) cuts out the image data for the display screen of the vehicle mounted terminal A ( 102 ) and stores the same in the buffer memory ( 23 ). Furthermore, an image transmission unit A ( 26 ) provides image data necessary for screen display by the vehicle mounted terminal B ( 103 ) when required by the vehicle mounted terminal B ( 103 ).

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to an information display apparatus that displays a screen display content of a mobile terminal on screens of a plurality of in-vehicle terminals. 
       BACKGROUND ART 
       [0002]    As display apparatuses that provide users with geographical information, music information. Internet information, or the like, in-vehicle or portable car navigation apparatuses, or information terminal apparatuses have been widely spread. In recent years, car navigation apparatuses capable of displaying an image on a plurality of display apparatuses and in-vehicle display control apparatuses that display screen data generated by a mobile terminal apparatus on an in-vehicle display have been know (see, Patent Literatures (hereinafter, abbreviated as PTLs) 1 and 2, for example). 
       CITATION LIST 
     Patent Literature 
     PTL 1  
       [0003]    Japanese Patent Application Laid-Open No, 2005-043695 (Claim 1 and FIG. 1) 
       PTL 2   
       [0004]    Japanese Patent Application Laid-Open No, 2009-281991 (Claim 1 and FIG. 1) 
       SUMMARY OF INVENTION 
     Technical Problem 
       [0005]    However, in the information display apparatus according to the related art, a screen of a mobile terminal is divided into a plurality of still images, and transferred to in-vehicle terminals, respectively, and thus the screen of the mobile terminal can be displayed in a divided manner on screens of two in-vehicle terminals, but when display regions of the two in-vehicle terminals overlap each other, the mobile terminal needs to transmit rectangular screen data including an overlapping portion to both of the in-vehicle terminals. Further, in a case where display-content updating intervals of the two in-vehicle terminals are not in synchronization with each other, even. When the screen content of one of the in-vehicle terminals is to be updated, the screen data needs to be transmitted to both of the in-vehicle terminals, so that there arises a problem in that the transfer amount of image data increases. Further, when it is necessary to perform a vehicle running regulation, the same process is executed in both of the in-vehicle terminals, and thus there arises a problem in that the processing load increases. 
         [0006]    It is an object of the present invention to provide an information display apparatus capable of minimizing the transfer amount of image data and reducing a running regulation processing load when a screen of a mobile terminal is displayed in a divided manner on screens of two in-vehicle terminals. 
       Solution to Problem 
       [0007]    In order to achieve the object mentioned above, an information display apparatus according to the present invention is configured in the following manner. More specifically, the information display apparatus according to the present invention is an information display apparatus that displays, in a divided manner an image of a mobile screen transmitted from a mobile terminal on a screen of a first in-vehicle terminal and a screen of a second in-vehicle terminal, the apparatus including: an image data acquiring section that collectively acquires screen data transmitted from the mobile terminal in the first in-vehicle terminal; a screen data distributing section that distributes the screen data acquired through the image data acquiring section into screen data necessary for displaying the screen of the first in-vehicle terminal and screen data necessary for displaying the screen of the second in-vehicle terminal; a distributed image storing section that stores the screen data distributed by the screen data distributing section; and an image data transmitting section that transmits, in response to a request from the second in-vehicle terminal, image data corresponding to the request from among the distributed image data stored in the distributed image storing section to the second in-vehicle terminal. 
       Advantageous Effects of Invention 
       [0008]    According to the present invention, when a screen of a mobile terminal is displayed in a divided manner on screens of two in-vehicle terminals, the transfer amount of image data can be minimized even when display regions of the two in-vehicle terminals overlap each other or even when display-content updating intervals of the two in-vehicle terminals are not in synchronization with each other. Further, it is possible to reduce a running regulation processing load. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0009]      FIG. 1  is a block diagram illustrating a configuration of an information display apparatus according to an embodiment of the present invention; 
           [0010]      FIG. 2  is an explanatory diagram illustrating a display screen of a mobile terminal of an information display apparatus according to an embodiment of the present invention; 
           [0011]      FIG. 3  is an explanatory diagram illustrating a display screen of in-vehicle terminal A of an information display apparatus according to an embodiment of the present invention; 
           [0012]      FIG. 4  is an explanatory diagram illustrating a display screen of in-vehicle terminal B of an information display apparatus according to an embodiment of the present invention; and 
           [0013]      FIG. 5  is a flowchart illustrating a processing flow of an information display apparatus according to an embodiment of the present invention. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0014]    Hereinafter, an information display apparatus according to an embodiment of the present invention will be described in detail with reference to the appended drawings. In all drawings for describing an embodiment, in principle, the same components are denoted by the same reference numerals, and a description thereof will not be repeated. 
         [0015]      FIG. 1  is a block diagram illustrating a configuration of an information display apparatus according to an embodiment of the present invention. Referring to  FIG. 1 , information display apparatus  100  includes single mobile terminal  101  and two in-vehicle terminals, that is, in-vehicle terminal A (first in-vehicle terminal)  102 . and in-vehicle terminal B (second in-vehicle terminal)  103 . image generating section  11  of mobile terminal  101  executes an application program such as a vehicle navigator, a music player, or a browser, and generates image data to be displayed on a mobile screen. Display memory section  12  stores the image data generated by image generating section  11 . 
         [0016]    Image display section  13  causes image data stored in display memory section  12  to be displayed on a mobile screen. Image transmitting section  14  transmits image data of region requested. from in-vehicle terminal A  102  among image data stored in display memory section  12  to in-vehicle terminal A  102 . 
         [0017]      FIG. 2  is an explanatory diagram illustrating a display screen of a mobile terminal of an information display apparatus according to an embodiment of the present invention. Referring to  FIG. 2 , display screen  201  of mobile terminal  101  has a rectangular shape including screen data region  202  of in-vehicle terminal A  102  and screen data regions  203  and  204  of in-vehicle terminal B  103 . When point O (0, 0) of  FIG. 2  is defined as the origin of a position of display screen  201  of mobile terminal  101  image transmitting section  14  of mobile terminal  101  receives, from in-vehicle terminal A  102 , a request for point C (x 1 , y 1 ) that is a clipping position of screen data region  202  of in-vehicle terminal A  102  and horizontal and vertical lengths (w 1 , h 1 ) of screen data region  202  of in-vehicle terminal A  102  as screen data region  202  of in-vehicle terminal A  102 . Further, image transmitting section  14  of mobile terminal  101  receives, from in-vehicle terminal A  102 , a request for point  1 ) (x 2 , y 2 ) that is a clipping position of screen data region  204  of in-vehicle terminal B  103  and horizontal and vertical lengths (w 2 , h 2 ) of screen data region  204  of in-vehicle terminal B  103  as screen data region  204  of in-vehicle terminal B  103 . 
         [0018]    Referring back to  FIG. 1 , image receiving section A (an image data acquiring section and an image data distributing section)  21  of in-vehicle terminal A  102  requests mobile terminal  101  to provide regions necessary for displaying the screen of in-vehicle terminal A  102  and in-vehicle terminal B  103  according to a running state of a vehicle, receives image data transmitted from mobile terminal  101 , and distributes necessary image data to in-vehicle terminal A  102  and in-vehicle terminal B  103 . In other words, image receiving section A  21  distributes image data of screen data region  203  and screen data region  204  of in-vehicle terminal B  103  illustrated in  FIG. 2  to in-vehicle terminal A  102  and in-vehicle terminal B  103 , respectively. 
         [0019]    Display memory section A (distributed image storing section)  22  stores image data necessary for displaying the screen of in-vehicle terminal A  102  distributed by image receiving section A  21 , and buffer memory section (clipped image storing section)  23  stores image data necessary for display the screen of in-vehicle terminal B  103  distributed by image receiving section A  211 . Image display section A  24  causes the image data stored in display memory section A  22  to be displayed on the screen of in-vehicle terminal A. Clipping processing section (image data clipping section  25  clips image data of a region necessary for displaying the screen of in-vehicle terminal B  103  requested from image receiving section A  21  from the image data stored in display memory section A  22 , and causes the clipped image data to be stored in buffer memory section  23 . 
         [0020]      FIG. 3  is an explanatory diagram illustrating a display screen of in-vehicle terminal A of an information display apparatus according to an embodiment of the present invention. Referring to  FIG. 3 , display screen  301  of in-vehicle terminal A  102  has a rectangular shape including screen data. region  302  of in-vehicle terminal A  102  and screen data region  303  of in-vehicle terminal B  103 . When point O (0, 0) is defined as the origin of a position of the display screen of in-vehicle terminal A  102 , display memory section A  22  stores screen data region  302  of in-vehicle terminal A  102  using an arrangement of point F (x 3 , y 3 ) that is arrangement position of screen data region  302  of in-vehicle terminal A  102  and horizontal and vertical lengths (w 3 , h 3 ) of screen data region  303  of in-vehicle terminal B  103 . Further, clipping processing section  25  clips screen data region  303  of in-vehicle terminal B  103  at a position of point F (x 4 , y 4 ) that is a clipping position of screen data region  303  of in-vehicle terminal B  103  and horizontal and vertical lengths (w 3 , h 3 ) of screen data region  303  of in-vehicle terminal B  103 , and causes the clipped region to be stored in buffer memory section  23 . 
         [0021]    Referring back to  FIG. 1 , image transmitting section A (image data transmitting section)  26  requests image receiving section A  21  to provide a region necessary for displaying the screen requested from in-vehicle terminal B  103 , and transmits image data stored in buffer memory section  23  to in-vehicle terminal B  103  according to the running state of a vehicle. Running regulation control section (distribution method changing section, and screen information changing section)  27  determines the running state of a vehicle based on in-vehicle sensor information such as a speed or an ON/OFF state of an emergency brake, and transfers the running state to image receiving section A  21  and image transmitting section A  26 . 
         [0022]    Image receiving section B  31  of in-vehicle terminal B  103  requests in-vehicle terminal A  102  to provide a region necessary for displaying the screen of in-vehicle terminal B  103 , and receives image data transmitted from in-vehicle terminal A  102 . Display memory section B  32  stores the image data received by image receiving section B  31 , and image display section B  33  causes the image data stored in display memory section B  32  to be displayed on the screen of in-vehicle terminal B  103 . 
         [0023]      FIG. 4  is an explanatory diagram illustrating a display screen of in-vehicle terminal B  103  of an information display apparatus according to an embodiment of the present invention. Referring to  FIG. 4 , display screen  401  of in-vehicle terminal B  103  has a rectangular shape including screen data region  402  and screen data region  403  of in-vehicle terminal B  103 . When point O (0,0) is defined as the origin of a position of the display screen of in-vehicle terminal B  103 , image receiving section B  31  causes screen data region  402  of in-vehicle, terminal B  103  and screen data region  403  of in-vehicle terminal B  103  to he stored in display memory section B  32  using an arrangement of point G (x 5 , y 5 ) that is an arrangement position of screen data region  402  of in-vehicle terminal B  103  and horizontal and vertical lengths (w 2 , h 2 ) of screen data region  402  of in-vehicle terminal B  103  and an arrangement of point H (x 6 , y 6 ) that is an arrangement position of screen data region  403  of in-vehicle terminal B  103  and horizontal and vertical lengths (w 3 , h 3 ) of screen data region  403  of in-vehicle terminal B  103 . 
         [0024]    A processing operation of the information display apparatus having the above configuration will be described with reference to a processing flow of a flowchart.  FIG. 5  is a flowchart illustrating the processing flow of information display apparatus  100  according to an embodiment of the present invention. In  FIG. 5 , steps S 101  to S 105  represent a process of mobile terminal  101 , steps S 201  to S 211  represent a process of in-vehicle terminal A  102 , and a process of steps S 301  to S 305  represent a process of in-vehicle terminal B  103 . 
         [0025]    First, the process of mobile terminal  101  will he described with reference to steps S 101  to S 105 . First, mobile terminal  101  performs an arrangement attribute information transmission process in step S 101 . Here, when an application program of mobile terminal  101  is activated, first, arrangement information, and attribute information of a predetermined mobile screen are transmitted from mobile terminal  101  to in-vehicle terminal A  102 . The arrangement information is defined as image information including horizontal and vertical sizes (the number of pixels) and upper left coordinate values of a plurality of rectangular images configuring a mobile screen. The attribute information is defined as a type (a map, a moving image, an operation button, a menu, or the like) of a rectangular image configuring a mobile screen. 
         [0026]    Then, in step S 102 , image generating section  11  of mobile terminal  101  executes an application program such as a car navigation, a music player, or a browser, generates image data to be displayed on a mobile screen, and writes the image data in display memory section  12 . 
         [0027]    Then, in step S 103 , image display section  13  reads application-rendering image data generated in step S 102  from display memory section  12 , and causes the image data to be displayed on the mobile screen. Then, in step S 104 , image transmitting section  14  checks whether there is a request for image data from in-vehicle terminal A  102 , and the process returns to step S 102  when it is determined that there is no request. 
         [0028]    Meanwhile, when it is determined in step S 104  that there is a request for image data from in-vehicle terminal A  102 , in step S 105 , image transmitting section  14  transmits a requested region of the image data generated in step S 102  from display memory section  12  to in-vehicle terminal A  102 , and the process returns to step S 102 . 
         [0029]    Then, the process of in-vehicle terminal A  102  will be described with reference to steps S 201  to S 211 . First, in-vehicle terminal A  102  performs an arrangement attribute information reception process in step S 201 , and performs a rectangular image selection arrangement process in step S 202 . In the process of step S 201  and step S 202 , in-vehicle terminal A  102  receives the arrangement information and the attribute information of the mobile screen from mobile terminal  101 . The user selects a rectangular image that is desired to be displayed on in-vehicle terminal A  102 , and defines the arrangement information as a “region necessary for displaying the screen” of in-vehicle terminal A  102 . Further, the user designates an arrangement position (AX, AY) on the screen of in-vehicle terminal A  102  for the selected rectangular image. 
         [0030]    Here, when the rectangular image data clipped from the mobile screen is displayed on the screen of in-vehicle terminal A  102  according to the “region necessary for displaying the screen,” the rectangular image data is defined as “necessary image data” in in-vehicle terminal A  102 . Further, when the “necessary image data” of in-vehicle terminal A is arranged at coordinate values (AX, AY) used as the origin at the upper left of the screen of in-vehicle terminal A, the “necessary image data” and the coordinate values (AX, AY) are defined as “necessary screen data” of in-vehicle terminal A. Then, the arrangement information and the attribute information of the mobile screen are transmitted. to in-vehicle terminal B  103 . 
         [0031]    Then, in step S 203 , in-vehicle terminal A  102  performs a running state/attribute information check A process. Here, whether or not the screen of in-vehicle terminal A  102  includes attribute information (for example, a moving image) that is prohibited from being displayed during running of the vehicle is checked. When the screen of in-vehicle terminal A  102  includes the attribute information that is prohibited from being displayed during running of the vehicle, a determination is made “according to the running state.” In other words, when the running state received from the riming regulation control section indicates “during stop of the vehicle,” it is determined to be a “region necessary for displaying the screen” of in-vehicle terminal A  102 , and when the running state indicates “during running of the vehicle,” it is determined to be a “region unnecessary for displaying the screen” of in-vehicle terminal A  102 . 
         [0032]    Then, in step S 204 , image receiving section A  21  requests mobile terminal  101  to provide regions necessary for displaying the screen of in-vehicle terminal A  102  and in-vehicle terminal B  103  according to the running state of a vehicle determined by running regulation control section  27 . 
         [0033]    Then, in step S 205 , image receiving section A  21  receives the image data transmitted from mobile terminal  101  in step S 105 . Then, in step S 206 , image receiving section A  21  distributes the image data received in step S 205  according to the display regions of in-vehicle terminal A  102  and in-vehicle terminal B  103 , and writes the distributed image data in display memory section A  22  and buffer memory section  23 . 
         [0034]    Then, in step S 207 , image display section A  24  causes the image data stored in display memory section A  22  in step S 206  to he displayed on the screen of in-vehicle terminal. A  102 . Then, in step S 208 , clipping processing section  25  clips the image data stored in display memory section A  22  in step S 206  according to a region designated by image receiving section A  21 , and writes the clipped image data in buffer memory section  23 . 
         [0035]    Then, in step S 209 , image transmitting section A  26  checks whether there is a request for image data from in-vehicle terminal B  103 , and the process returns to step S 203  when it is determined that there is no request. Meanwhile, when it is determined in step S 209  that there is a request for image data from in-vehicle terminal B  103 , in-vehicle terminal A  102  performs a running state/attribute information cheek B process in step S 210 . Here, whether or not the screen of in-vehicle terminal B  103  includes attribute information (for example, a moving image) that is prohibited from being displayed during running of the vehicle is determined. When the screen of in-vehicle terminal B  103  includes the attribute information that is prohibited from being displayed during running of the vehicle, a determination is made “according to the running state.” in other words, When the running state received from the running regulation control section indicates “during stop of the vehicle,” it is determined to be a “region necessary for screen display” of in-vehicle terminal B  103 , and when the running state indicates “during running of the vehicle,” it is determined to be a “region unnecessary for screen display” of in-vehicle terminal B  103 . 
         [0036]    Then, in step S 211 , image transmitting section A  26  transmits a region requested from in-vehicle terminal B  103  to image receiving section A  21 . Further, image transmitting section A  26  transmits, to in-vehicle terminal B  103 , image data of the region requested from in-vehicle terminal B  103  according to the running state of a vehicle determined by running regulation control section  27  from the image data stored in buffer memory section  23  written in step S 206  and step S 208 , and then the process proceeds to step S 203 . 
         [0037]    Then, the process of in-vehicle terminal B  103  will be described with reference to steps S 301  to S 305 . First, in step S 301  and step S 302 , in-vehicle terminal B  103  performs the arrangement attribute information reception process and the rectangular image selection arrangement process. Here, the arrangement information and the attribute information of the mobile screen are received from in-vehicle terminal A  102 . The user selects a rectangular image that is desired to be displayed on in-vehicle terminal B  103 , and defines the arrangement information as a “region necessary for screen display” of in-vehicle terminal B  103 . 
         [0038]    Further, the user designates an arrangement position (BX, BY) on the screen of in-vehicle terminal B  103  for the selected rectangular image. Here, when the rectangular image data clipped from the mobile screen is displayed on the screen of in-vehicle terminal B  103  according, to the “region necessary for screen display,” the rectangular image data is defined as “necessary image data” in in-vehicle terminal B  103 . Further, when the “necessary image data” of in-vehicle terminal B  103  is arranged at coordinate values (BX, BY) used as the origin at the upper left of the screen of in-vehicle terminal B  103 , the “necessary image data” and the coordinate values (BX, BY) are defined as “necessary screen data” of in-vehicle terminal B  103 . 
         [0039]    Then, in step S 303 , image receiving section B  31 . requests in-vehicle terminal A  102  to provide a region necessary for displaying the screen of in-vehicle terminal B  103 . Then, in step S 304 , image receiving section B  31  receives the image data transmitted from in-vehicle terminal A  102  in step S 304 , and writes the received image data in display memory section B  32 . 
         [0040]    Then, in step S 305 , image display section B  33  causes the image data stored in display memory section B  32  in step S 304  to he displayed on the screen of in-vehicle terminal B  103 , and then the process returns to step S 303 . 
         [0041]    As described above, according to the information display apparatus of the present embodiment. When a screen of a mobile terminal is displayed in a divided manner on screens of two in-vehicle terminals, one in-vehicle terminal receives screen data necessary in both in-vehicle terminals from the mobile terminal, stores image data necessary in the other in-vehicle terminal in a buffer memory, and provides the image data when there is a request from the other in-vehicle terminal. Thus, even when display regions of the two in-vehicle terminals overlap or even when display-content updating intervals of the two in-vehicle terminals are not in synchronization with each other, the transfer amount of image data can be minimized. In addition, one in-vehicle terminal collectively performs the running regulation process, so that the running regulation processing load in the other in-vehicle terminal can be reduced. 
         [0042]    It should be noted that, the functional blocks used in the description of the embodiment described above are typically implemented as LSI devices, which are integrated circuits. The functional blocks may he formed as individual chips, or a part or all of the functional blocks may be integrated into a single chip. The term “LSI” is used herein, but the terms “IC,” “system LSI,” “super LSI” or “ultra LSI” may he used as well depending on the level of integration. In addition, the circuit integration is not limited to LSI and may be achieved by dedicated circuitry or a general-purpose processor other than an LSI. After fabrication of LSI, a field programmable gate array (FPGA), which is programmable, or a reconfigurable processor which allows reconfiguration of connections and settings of circuit cells in LSI may be used. Moreover, should a circuit integration technology replacing LSI appear as a result of advancements in semiconductor technology or other technologies derived flout the technology, the functional blocks could be integrated using such a technology. Another possibility is the application of biotechnology, for example. 
         [0043]    The information display apparatus according to the present invention has been specifically described thus far based on the embodiment. The present invention, however, is not limited to the embodiment, and various modifications are possible within a scope not departing from the gist of the present invention. 
         [0044]    The disclosure of the specification, drawings, and abstract included in Japanese Patent Application No. 2012-74532 filed on Mar. 28, 2012 is incorporated herein by reference in its entirety. 
       INDUSTRIAL APPLICABILITY 
       [0045]    The image display apparatus of the present invention brings about an effect capable of minimizing the transfer amount of image data and reducing a running regulation processing load when a screen of a mobile terminal is displayed in a divided manner on screens of two in-vehicle terminals, so that the image display apparatus of the present invention can be used in the fields of design and manufacturing of in-vehicle vehicle navigation apparatuses, information terminal apparatuses, portable navigation apparatuses, and information terminal apparatuses. 
       REFERENCE SIGNS LIST 
       [0046]      11  Image generating section 
         [0047]      12  Display memory section 
         [0048]      13  Image display section 
         [0049]      14  Image transmitting section 
         [0050]      21  Image receiving section A 
         [0051]      22  Display memory section A 
         [0052]      23  Buffer memory section 
         [0053]      24  Image display section A 
         [0054]      25  Clipping processing section 
         [0055]      26  image transmitting section A 
         [0056]      27  Running regulation control section 
         [0057]      31  Image receiving section B 
         [0058]      32  Display memory section B 
         [0059]      33  Image display section B 
         [0060]      100  Information display apparatus 
         [0061]      101  Mobile terminal 
         [0062]      102  In-vehicle terminal A (first in-vehicle terminal) 
         [0063]      103  In-vehicle terminal B (second in-vehicle terminal) 
         [0064]      201  Display screen of mobile terminal 
         [0065]      202  Screen data region of in-vehicle terminal A 
         [0066]      203 ,  204  Screen data region of in-vehicle terminal B 
         [0067]      301  Display screen of in-vehicle terminal A 
         [0068]      302  Screen data region of in-vehicle terminal A 
         [0069]      303  Screen data region of in-vehicle terminal B 
         [0070]      401  Display screen of in-vehicle terminal B 
         [0071]      402 ,  403  Image data region of in-vehicle terminal B