CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority to and incorporates by reference the entire contents of Japanese Patent Application No. 2013-064927 filed in Japan on Mar. 26, 2013. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a computer program product, an information processing method, and an information processing apparatus. 
     2. Description of the Related Art 
     Japanese Patent Application Laid-open No. 2001-24976, for example, discloses a technique that, when an external display device is connected to an image processing apparatus having a display device, changes a display destination from the display device of the image processing apparatus to the external display device. 
     Unfortunately, however, the related-art technique at times fails to properly perform changeover (changeover of the display destination) between the built-in display device (hereinafter referred to as an “internal display”) and the external display device (hereinafter referred to as an “external display”). 
     The changeover between the internal display and the external display is achieved, for example, through execution of application software that provides a display control function. The display control function in this case includes a function of detecting connection of the external display and a function of generating, based on the detection result, a display screen (user interface, or UI) corresponding to the display destination. These sub-functions are implemented in the form of, for example, different modules (software components) such as a detection module and a UI module, and the UI module receives a detection event from the detection module and generates the UI for the new display destination. Thus, if, for example, the UI module has a starting time longer than a starting time of the detection module, the UI module is unable to receive the detection event from the detection module. As such, with the related-art technique, the display destination may not be properly changed over during starting of the display control function. 
     In view of the foregoing, there is a need to provide a computer program product, an information processing method, and an information processing apparatus that can properly change over the display destination even during starting of the display control function. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to at least partially solve the problems in the conventional technology. 
     A computer program product includes a non-transitory computer-usable medium having computer-readable program codes embodied in the medium. The program codes when executed cause a computer to execute: detecting a connection status of an externally connected second display different from a built-in first display; writing status information indicating the detected connection status in a storage, changing over a display destination between the first display and the second display based on the detected connection status, and controlling a display screen according to screen specifications of the first display or the second display, which corresponds to the display destination after changeover; and reading the connection status written in the storage and scaling a display image at a magnification based on the read connection status. 
     An information processing method includes: detecting a connection status of an externally connected second display different from a built-in first display; writing status information indicating the detected connection status in a storage, changing over a display destination between the first display and the second display based on the detected connection status, and controlling a display screen according to screen specifications of the first display or the second display, which corresponds to the display destination after changeover; and reading the connection status written in the storage and scaling a display image at a magnification based on the read connection status. 
     An information processing apparatus includes: a detection unit that detects a connection status of an externally connected second display different from a built-in first display; a control unit that writes status information indicating the detected connection status in a storage, changes over a display destination between the first display and the second display based on the detected connection status, and controls a display screen according to screen specifications of the first display or the second display, which corresponds to the display destination after the changeover; and a scaling unit that reads the connection status written in the storage and scales a display image at a magnification based on the read connection status. 
     The above and other objects, features, advantages and technical and industrial significance of this invention will be better understood by reading the following detailed description of presently preferred embodiments of the invention, when considered in connection with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a diagram illustrating an exemplary configuration of an information processing system according to a first embodiment; 
         FIG. 2  is a diagram illustrating an exemplary hardware configuration of an information processing apparatus according to the first embodiment; 
         FIG. 3  is a diagram illustrating an exemplary configuration of a display control function according to the first embodiment; 
         FIG. 4  is a sequence diagram illustrating exemplary processing procedure (part 1) at the time of display control according to the first embodiment; 
         FIG. 5  is a sequence diagram illustrating exemplary processing procedure (part 2) at the time of the display control according to the first embodiment; 
         FIG. 6  is a flowchart illustrating exemplary processing procedure when detecting an external display according to the first embodiment; and 
         FIG. 7  is a flowchart illustrating exemplary processing procedure at the time of scaling according to the first embodiment. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     An information processing program, an information processing method, and an information processing apparatus according to an embodiment of the present invention will be described in detail below with reference to the accompanying drawings. 
     First Embodiment 
     System Configuration 
       FIG. 1  is a diagram illustrating an exemplary configuration of an information processing system  1000  according to a first embodiment.  FIG. 1  illustrates an exemplary conference system using a plurality of information processing apparatuses  100   a   1 ,  100   a   2 ,  100   b   1 ,  100   b   2 . The information processing apparatuses  100   a   1 ,  100   a   2  are connected to an internal network Na and the information processing apparatuses  100   b   1 ,  100   b   2  are connected to an internal network Nb. The networks Na, Nb (to be collectively called a “network N”) each correspond to, for example, a local area network (LAN). Additionally, the network N is connected to an external network I. The external network I corresponds to, for example, a wide area network (WAN) or the Internet. Thus, in the information processing system  1000  according to the embodiment, the information processing apparatuses  100   a   1 ,  100   a   2  and the information processing apparatuses  100   b   1 ,  100   b   2  can perform data communication via the external network I. Additionally, the information processing system  1000  according to the embodiment includes a computer program providing apparatus  300  connected to the external network I. The computer program providing apparatus  300 , for example, provides the information processing apparatuses  100   a   1 ,  100   a   2 ,  100   b   1 ,  100   b   2  with computer programs over the external network I. 
     As illustrated in  FIG. 1 , the information processing apparatuses  100   a   1 ,  100   a   2 ,  100   b   1 ,  100   b   2  include internal displays  119   a   1 ,  119   a   2 ,  119   b   1 ,  119   b   2 , respectively. The information processing apparatuses  100   a   1 ,  100   a   2 ,  100 / b   1 ,  100   b   2  will hereinafter be collectively called an “information processing apparatus  100 ”. The internal displays  119   a   1 ,  119   a   2 ,  119   b   1 ,  119   b   2  will hereinafter be collectively called an “internal display  119 ”. 
     The information processing apparatuses  100   a   1 ,  100   b   1  further include external displays  200   a ,  200   b  having screen specifications (e.g., “display area size” and “resolution”) different from those of the internal displays  119   a   1 ,  119   b   1 , respectively. The external displays  200   a ,  200   b  will hereinafter be collectively called an “external display  200 ”. 
     The information processing apparatus  100  according to the embodiment has a display control function, performing display control to change over a display destination between the internal display  119  and the external display  200 . The information processing apparatus  100  corresponds, for example, to a personal computer (PC), a conference-dedicated terminal, a smartphone, a tablet terminal, a portable telephone, or a projector. The internal display  119  and the external display  200  are display devices that display various types of images, such as a moving image and a still image. With the projector, a screen or other projecting plane on which a projected image is displayed corresponds to the internal display  119 . 
     The information processing system  1000  according to the embodiment, having the system configuration as described above, can provide the following conference service. For example, the information processing system  1000  uses the information processing apparatus  100   a   1  connected to the network Na to make a connection request (a conference attendance request) to the information processing apparatus  100   a   2  connected to the same network Na. Additionally, the information processing system  1000  uses the information processing apparatus  100   a   1  connected to the network Na to make a connection request (a conference attendance request) via the external network I to the information processing apparatuses  100   b   1 ,  100   b   2  connected to the network Nb. When the information processing apparatuses  100   a   2 ,  100   b   1 ,  100   b   2  then respond to the connection requests (conference attendance requests), two-way data communication is established between the information processing apparatus  100   a   1  and each of the information processing apparatuses  100   a   2 ,  100   b   1 ,  100   b   2 . Through such call control, the information processing system  1000  starts providing conference service using two-way communication using various types of content, such as text, images (including still images and moving images), and audio. At this time, the internal display  119  of the information processing apparatus  100  displays image content including images of conference attendees and conference material. If the external display  200  is connected to the information processing apparatus  100  at this time, the display destination is changed over from the internal display  119  to the external display  200  to display the image content on the external display  200 . 
     Possible systems of the above call control include (1) a session initiation protocol (SIP) and (2) H.323. In addition, the possible call control systems include (3) a SIP-extended protocol and (4) an instant messenger protocol. The possible call control systems may further include (5) a protocol utilizing a SIP message method and (6) an Internet relay chat (IRC) protocol. The possible call control systems may still include (7) an instant messenger protocol-extended protocol. Of the protocols cited above, (4) the instant messenger protocol is used in, for example, (4-1) extensible messaging and presence protocol (XMPP) and (4-2) ICQ (registered trademark). In addition, (4) the instant messenger protocol is used in, for example, AIM (registered trademark) and Skype (registered trademark). (7) The instant messenger protocol-extended protocol is, for example, Jingle. 
     As an image encoding system, H.264/AVC or H.264/SVC, for example, may be used. Still, any other encoding system may be used. 
     In addition, the call control between the different information processing apparatuses  100  may be performed via, for example, a call control server. Data communication among the different information processing apparatuses  100  may be performed via a repeater that relays various types of content. 
     Hardware Configuration 
       FIG. 2  is a diagram illustrating an exemplary hardware configuration of the information processing apparatus  100  according to the embodiment. As illustrated in  FIG. 2 , the information processing apparatus  100  according to the embodiment includes, for example, a central processing unit (CPU)  101 . The information processing apparatus  100  further includes a read only memory (ROM)  102  and a random access memory (RAM)  103 . The information processing apparatus  100  further includes a flash memory  104 , a solid state drive (SSD)  105 , and a media drive  107 . The information processing apparatus  100  further includes an operating button  108 , a power switch  109 , a built-in power supply  110 , and an external power supply IF  111 . The information processing apparatus  100  further includes a communication IF  112 , a camera  113 , an image capturing device IF  114 , a microphone  115 , a speaker  116 , and an audio input/output IF  117 . The information processing apparatus  100  further includes an external display IF  118 , the internal display  119 , an internal display IF  120 , and an external device IF  121 . In the information processing apparatus  100 , the foregoing components are connected to each other by a bus B. 
     The CPU  101  is an arithmetic unit that controls the whole of the information processing apparatus  100 . The ROM  102  is a nonvolatile semiconductor memory that can retain internal data even with power turned off. The ROM  102  stores therein, for example, computer programs executed upon the start of the information processing apparatus  100 , and data. The RAM  103  is a volatile semiconductor memory. The CPU  101  loads, for example, a computer program or data from the ROM  102  on the RAM  103  and performs processing, thereby achieving control of the whole of the information processing apparatus  100  and functions implemented thereon. 
     The flash memory  104  is a nonvolatile semiconductor memory, such as, for example, a flash electrically erasable programmable ROM (EEPROM) and a flash ROM. The SSD  105  reads data from, and writes data to, the flash memory  104 . The media drive  107  reads data from, and writes data to, a storage medium  106 . Non-limiting examples of the storage medium  106  include a flexible disk, a compact disc (CD), a digital versatile disc (DVD), a memory card. 
     The operating button  108  is a user interface (UI) used for inputting operating signals to the information processing apparatus  100 . The power switch  109  turns on or off supply of electric power to the information processing apparatus  100 . The built-in power supply  110  supplies driving electric power from the inside of the information processing apparatus  100 , not from the outside. The built-in power supply  110  may, for example, be a storage battery such as a battery. The external power supply IF  111  serves as an interface between a power supply that supplies the information processing apparatus  100  with driving electric power from the outside and the information processing apparatus  100 . With an external power supply from an outlet, for example, a plug corresponds to the external power supply IF  111 . 
     The communication IF  112  is an interface that connects the information processing apparatus  100  to a predetermined data transmission path, such as the network N. The camera  113  includes an optical system engine, such as a lens and captures an image by receiving incident light with an image capturing device. The image capturing device IF  114  serves as an interface that performs data transfer between each of various types of optical system devices, such as the camera  113 , and the information processing apparatus  100 . The microphone  115  detects sound using, for example, a sensor. The speaker  116 , for example, reproduces detected sound data or predetermined audio content to thereby output sound. The audio input/output IF  117  serves as an interface that performs data transfer between each of various types of audio input/output devices, such as the microphone  115  and the speaker  116 , and the information processing apparatus  100 . 
     The external display IF  118  and the internal display IF  120  serve as interfaces that perform data transfer between the external display  200  and the internal display  119 , respectively, and the information processing apparatus  100 . The external display  200  and the internal display  119  may, for example, be a liquid crystal display that displays a result of processing performed by the information processing apparatus  100 . The external device IF  121  serves as an interface that performs data transfer between each of various types of external devices, such as a PC, a smartphone, a tablet terminal, and a portable telephone, and the information processing apparatus  100 . The external device IF  121  may be connected with, for example, an external storage device such as a hard disk drive (HDD) and a microdrive. 
     As described above, the information processing system  1000  according to the embodiment can provide, through the above-described configuration, conference service using two-way communication using various types of content between remote sites (for example, “between different networks”). 
     Display Control Function 
     The display control function according to the embodiment will be described. The information processing apparatus  100  according to the embodiment detects a connection status of the external display  200 . Based on the detected connection status, the information processing apparatus  100  changes over the display destination between the internal display  119  (a first display) and the external display  200  (a second display) and controls the display screen according to the screen specifications of the display corresponding to the display destination after the changeover. At this time, in the information processing apparatus  100 , a detection module stores in memory the detected connection status of the external display  200  and notifies a UI module that writing (storing in memory) has been completed. When the UI module receives the notification of the completion of writing, the information processing apparatus  100  acquires the connection status of the external display  200  stored in memory and, based on the acquired information, performs scaling and setting of resolution of the display image corresponding to the external display  200 . The information processing apparatus  100  according to the embodiment has such a display control function. 
     The related-art technique may fail to properly perform changeover between the internal display  119  and the external display  200  at the start of the display control function. The display control function, if achieved through execution of application software, includes the detection module that detects the connection of the external display  200  and the UI module that generates the display screen corresponding to the display destination based on the detection result. 
     The information processing apparatus  100  having the display control function may encounter the following use situation. Specifically, for example, the external display  200  is connected to the information processing apparatus  100  in advance before the information processing apparatus  100  is turned on. When the information processing apparatus  100  is turned on under the foregoing condition, the detection module and the UI module are started. This causes the detection module to detect the connection of the external display  200  and to notify the UI module of the detection event. If the UI module is yet to complete starting at this time, the UI module is unable to receive the notified detection event. Specifically, the UI module fails to receive the detection event notified during its starting during which the UI module is unable to receive events. As a result, the information processing apparatus  100  is unable to generate the display screen corresponding to the external display  200  to which the changeover is to be performed, and unable to change over the display destination to the external display  200 . As such, the related-art technique may fail to properly change over the display destination during the starting of the display control function. 
     The display control function to change over the display destination is utilized, for example, in conference service as described with reference to  FIG. 1 . In conference service use situations, the external display  200  having a larger screen than that of the internal display  119  is very often used to ensure smooth communication during the conference. Also from this viewpoint, it is preferable that the display control function can properly change over the display destination based on the result of detection of the external display  200 , regardless of the order in which the modules complete starting. 
     Thus, the display control function according to the embodiment has a system of controlling the changeover of the display screen corresponding to the display destination, in which the connection status of the detected external display  200  is stored, the stored connection status is determined according to the notification of the completion of storage, and the display screen is changed based on the result of the determination. 
     This allows the display control function according to the embodiment to provide an environment in which the display destination is changed over properly based on the result of detection of the external display  200 , regardless of the order in which the modules complete starting. As a result, the display control function according to the embodiment can appropriately change over the display destination even during starting of the display control function. 
     The configuration and operations of the display control function according to the embodiment will be described below.  FIG. 3  illustrates an exemplary configuration of the display control function according to the embodiment. As illustrated in  FIG. 3 , the display control function according to the embodiment includes a display control unit  11 , a scaling unit  12 , a starting unit  21 , an information acquiring unit  22 , and a setting unit  23 . It is noted that, in the embodiment, the functions of the display control unit  11  and the scaling unit  12  are achieved by, for example, application software, such as a program, installed in the information processing apparatus  100 . It is further noted that, in the embodiment, the function of the display control unit  11  is achieved by software including the detection module and the function of the scaling unit  12  is achieved by software including the UI module. Thus, in the embodiment, the functions of the display control unit  11  and the scaling unit  12  are achieved by the modules different from each other. In addition, in the embodiment, the functions of the starting unit  21 , the information acquiring unit  22 , and the setting unit  23  are achieved by, for example, basic software, such as an operating system (OS), installed in the information processing apparatus  100 . Specifically, the display control function according to the embodiment is achieved through cooperation between the basic software and the application software operating on the basic software. 
     The display control unit  11  controls the display screen according to the screen specifications of the display corresponding to the display destination based on a change in status of the information processing apparatus  100  during or after the starting. The display control unit  11  requests the information acquiring unit  22  to inquire about a device status of the external display  200  and receives a device status response (receives status information of the external display  200 ). The display control unit  11  changes over the display destination between the internal display  119  and the external display  200  based on the received device status response. 
     The display control unit  11  includes a detection unit  11   a  that detects the change in status of the information processing apparatus  100  using the above method of receiving a status response. The detection unit  11   a  (that corresponds to the detection module) detects the change in status of the information processing apparatus  100  during and after the starting. Changes in status to be detected include a status change of the external display  200 , either connected or disconnected. Specifically, the changes in status to be detected include a status change when the external display  200  becomes connected to the information processing apparatus  100  and a status change when the external display  200  becomes detached (disconnected) from the information processing apparatus  100 . The basic software detects the change in status of the information processing apparatus  100  based on, for example, a signal input thereto via the external display IF  118  (an input signal from the external display  200 ). As a result, the basic software gives an event notification for the detection result to the detection unit  11   a . Possible notification methods employed at this time include using an event function of the basic software and using an enhanced event function for a uniquely defined event. Receiving the notification, the detection unit  11   a  detects the change in status of the information processing apparatus  100 . This allows the application software to detect the change in status of the information processing apparatus  100 , including whether the external display  200  has become connected or disconnected. 
     The embodiment assumes, as a situation in which the change in status of the information processing apparatus  100  during starting occurs, an exemplary case in which the information processing apparatus  100  to which the external display  200  is connected is started. This is, however, not the only possible situation assumed with the information processing apparatus  100  according to the embodiment. The information processing apparatus  100  according to the embodiment can even handle a change in status as described in the following through cooperative operations between the basic software and the detection unit  11   a . For example, situations in which the change in status after starting occurs and that the information processing apparatus  100  can handle include a case in which the information processing apparatus  100  to which the external display  200  is yet to be connected is started and then the external display  200  is connected to the information processing apparatus  100  and a case in which the external display  200  is disconnected after the information processing apparatus  100  has been started. 
     If the external display  200  is in a state where it can perform display, the display control unit  11  turns off the internal display  119  and instructs the scaling unit  12  (that corresponds to the UI module) to scale the display image according to the screen specifications of the external display  200 . The display control unit  11 , for example, instructs the internal display  119  to turn off through an application program interface (API) for display drive control of the basic software (by calling an API function). Next, the display control unit  11  writes a value that indicates the device status received in the device status response (hereinafter referred to as “device status information”) in a registry  90  (storage unit) (updates a default value of the device status information stored in the registry), thereby storing the device status of the external display  200 . It is here noted that the registry refers to an information database (DB) used by the basic software, corresponding to a predetermined storage space of a storage included in the information processing apparatus  100 . Additionally, the value that indicates the device status of the internal display  119  is set as the default value of the device status information stored in the registry  90 . On completing writing the device status information (completing storing the information), the display control unit  11  thereafter issues an event notifying the completion of writing (storage completion event). The display control unit  11  notifies the scaling unit  12  that writing of the device status of the external display  200  is completed by notifying the issued event. The scaling unit  12 , having received the notification, scales the display image based on the device status information of the external display  200  stored in the registry  90  to thereby generate a display screen corresponding to the external display  200 . 
     Methods for notifying the writing completion event include, for example, assigning the writing completion event to a predetermined keyboard event. Additionally, the method for notifying the completion of writing may be a registry notification. A possible method for this case is, for example, setting a value indicating the writing completion notification as a predetermined registry value. The display control unit  11  sends a writing completion notification to the scaling unit  12  through the foregoing method via an event or registry notification API of the basic software. 
     If the external display  200  is in a state where it can perform display, the display control unit  11  requests the information acquiring unit  22  to inquire about device performance of the external display  200  and receives a device performance response (receives performance information of the external display  200 ). Based on the received device performance response, the display control unit  11  instructs the setting unit  23  to set resolution in compliance with the screen specifications of the external display  200 . The display control unit  11  passes the value of the resolution included in the received device performance response to the setting unit  23 , thereby directing the setting of the resolution. Meanwhile, if the external display  200  is not in a state where it can perform display, the display control unit  11  directs the setting of resolution in compliance with the screen specifications of the internal display  119 . 
     The scaling unit  12  scales the display image according to the screen specifications of the display corresponding to the display destination. When, for example, the conference service as described with reference to  FIG. 1  is to be provided, the following countermeasure needs to be made. To clarify the countermeasure, a specific situation in which the conference service is used will first be described. 
     In conference service, an identical image is displayed on an information processing apparatus  100  at a local site and an information processing apparatus  100  at a remote site. At this time, for example, the information processing apparatus  100  at the local site transmits image data of conference material saved therein to the information processing apparatus  100  at the remote site. This results in the same image being displayed on the information processing apparatus  100  at the local site and the information processing apparatus  100  at the remote site. 
     This enables the image of the same conference material to be viewed at the local site and the remote site, thus achieving smooth communication. It is noted that the local site corresponds to a place at which oneself is present and the remote site corresponds to a place at which a remote attendee is present, the local conference site being different from the remote conference site. 
     In such a use situation, the image data is generally generated according to a predetermined format (e.g., “size” and “resolution”) common to both the information processing apparatus  100  at the local site and the information processing apparatus  100  at the remote site. While transmitting the image data to the information processing apparatus  100  at the remote site on one hand, the information processing apparatus  100  at the local site needs, on the other, to scale the same image data as that transmitted to the remote site to an appropriate size according to the display screen at the local site before the same image can be displayed on the information processing apparatus  100  at the local site. In conference service use situations, preferably, the information processing apparatus  100  can support such a requirement in order to provide an environment that achieves smooth communication. Thus, the information processing apparatus  100  according to the embodiment includes the scaling unit  12  that supports the above-described requirement. 
     The scaling unit  12  refers to the registry  90  and reads (acquires) the device status information of the display destination. Based on the read device status information, the scaling unit  12  identifies the display destination after the changeover and performs a scaling process on the display image to make the display image correspond to the identified display destination. The scaling unit  12 , on receipt of the writing completion event notification from the display control unit  11 , reads the device status of the external display  200  stored in the registry  90  and identifies the external display  200  as the display destination. It is noted that, before receiving the writing completion event notification from the display control unit  11 , the scaling unit  12  refers to the default value of the device status information stored in the registry  90  and sets the internal display  119  as the display destination. 
     Having identified the display destination after the changeover, the scaling unit  12  performs the scaling process for the display screen corresponding to the display destination through the method described below. The scaling unit  12  first identifies a display area before the changeover (a vertical length H 1 , a horizontal length W 1 ) and a display area after the changeover (a vertical length H 2 , a horizontal length W 2 ) based on predetermined specifications of display areas for different types of displays. Then, based on size ratios of the identified display area (a vertical length ratio H 2 /H 1 , a horizontal length ratio W 2 /W 1 ), the scaling unit  12  obtains a magnification (an enlarging ratio or a reducing ratio) of the display image. 
     The scaling unit  12  may store display image magnifications previously obtained for each of possible different display destination changeover patterns based on the screen specifications of each of the internal display  119  of the information processing apparatus  100  and the external display  200  to be connected to the information processing apparatus  100 . For example, let ‘1’ be the magnification of the external display  200 ; then, the magnification corresponding to the internal display  119  having a display area smaller than that of the external display  200  is set to be ‘0.85’ and the magnification values of ‘1’ and ‘0.85’ may be stored. If the magnifications are stored in this way, the scaling unit  12  identifies the display destination changeover pattern (either a changeover from the internal display  119  to the external display  200  or a changeover from the external display  200  to the internal display  119 ). As a result, the scaling unit  12  acquires, based on the identification result, a specific magnification corresponding to the display destination changeover pattern selected from among the stored magnifications. This allows the scaling unit  12  to scale the display image, even if the display control unit  11  is unable to acquire the device information including the screen specifications from the external display  200  via the information acquiring unit  22 . 
     Then, the scaling unit  12  scales the display image before the changeover based on the obtained magnification or the acquired magnification. At this time, the scaling unit  12  achieves this task by generating display data in compliance with a predetermined data format capable of being processed by the UI function (a display screen drawing function) of the display corresponding to the display destination. The scaling unit  12  generates display data for scaling the display image according to the data format capable of being processed by the UI function of the display destination. Languages of the data format as used here include, for example, HyperText Markup Language (HTML)/Cascading Style Sheets (CSS). In accordance with the language specifications of the data format, the scaling unit  12  generates the display data in which image data of the display image (display image data) is embedded and the magnification value is set as a parameter value for the image scaling process. If the language of the data format is HTML, the image data is embedded using a definition tag, such as an image tag. The parameter value for the image scaling process may be set by setting the value of an enlarging ratio or a reducing ratio in an attribute value, such as transform:scale( ). As a result, at the display corresponding to the display destination, the display data is processed by the UI function implemented therein and the display screen is drawn based on the processing result on the display. This results in the display image being displayed on the display screen while being enlarged or reduced at the set magnification. 
     The above-described display image includes, for example, image data generated by the information processing apparatus  100  and previously stored image data. The display image further includes image data received from another information processing apparatus  100  via the communication IF  112  and image data received from an external device connected via the external device IF  121 . 
     In conference service use situations, the information processing apparatus  100  at the local site first generates image data of the display image according to the predetermined format. The information processing apparatus  100  at the local site next functions as a transmitting unit and transmits the generated image data to the information processing apparatus  100  at the remote site. At this time, the scaling unit  12  of the information processing apparatus  100  at the local site performs a scaling process for displaying the same image on the information processing apparatus  100  at the local site after or before the image data is transmitted. At this time, the scaling unit  12  scales the display image with contents identical to those of the image data to be transmitted to thereby change the size (image size). 
     In this way, the embodiment stores the detected connection status of the external display  200  and, according to a storage completion notification, confirms the stored connection status; then, based on the confirmation result, the embodiment controls the changeover of the display screen corresponding to the display destination. This enables the embodiment to change over the display destination appropriately based on the detection result of the external display  200  regardless of the order in which starting of the different modules is completed. That is, the embodiment is free from the problem that the UI module fails to receive an event notified during its starting during which the UI module is unable to receive events. Thus, the embodiment is also free from the problem that the display screen corresponding to the external display  200  to which changeover is to be performed is not generated, and the display destination is not changed over to the external display  200 . As a result, the information processing apparatus  100  according to the embodiment can change over the display destination appropriately even during the starting of the display control function. 
     In addition, the embodiment uses a common UI function between the internal display  119  and the external display  200  to scale the display image, eliminating the need for individual handling (generating the display data individually). Specifically, in the embodiment, the internal display  119  and the external display  200  use the common display data to scale the display image. This simplifies the scaling process and reduces processing load. 
     The starting unit  21  starts the application software (a group of modules that achieve different functions) that provides the display control function. The starting unit  21 , for example, requests a computer program (corresponding to an individual module) that achieves the function of the display control unit  11  or a computer program that achieves the function of the scaling unit  12  to start, and the computer program is thus executed. 
     The information acquiring unit  22  acquires various types of information from the external display  200  according to the request made from the display control unit  11 . The information acquiring unit  22  sends a query about the device status to the external display  200  via the external display IF  118  and acquires, for example, status information that indicates a displayable status or an non-displayable status. The information acquiring unit  22  also sends a query about the device performance to the external display  200  via the external display IF  118  and acquires performance information including, for example, resolution. Examples of the performance information acquired at this time include general-purpose data that represents hardware performance retained in advance by the display for connection to various types of devices. The information acquiring unit  22  passes the acquired information to the display control unit  11  that made the request. 
     The following briefly describes the abovementioned general-purpose data as an example of the performance information acquired by the information acquiring unit  22 . Displays achieve a plug-and-play feature (automatic detection and automatic connection) with the device to which they are connected. To connect a PC and a display, it is generally required that a video signal output from the PC be brought to fall within ranges of frequency and resolution supported by the display. The frequency includes horizontal and vertical scanning frequencies and a clock frequency of the video signal. The resolution means hardware performance of the configuration of dots in the horizontal and vertical directions. To achieve the plug-and-play feature, the PC needs to acquire these types of information from the display using some suitable means. Extended display identification data (EDID) is available for use as the general-purpose data enabling the connection with various types of devices. The EDID represents 128-byte binary data that describes characteristics unique to the display, such as the frequency and resolution supported by the display, and the name of manufacturer (vendor ID) and the model (product ID) of the display. The EDID is retained in a storage of the display. The EDID may include an extended block with a size of more than 128 bytes. 
     In response to a request from the display control unit  11 , the setting unit  23  sets the resolution for the display corresponding to the display destination. At this time, the setting unit  23  sets the resolution for the external display  200  based on the value of the resolution received from the display control unit  11 . Meanwhile, the setting unit  23  sets the resolution for the internal display  119  based on the value of the resolution stored in advance. 
     As described heretofore, the display control function according to the embodiment is achieved by implementation of the software. Specifically, the display control function is achieved by executing an information processing program that achieves the display control function and cooperatively operating the above-described functional units in the information processing apparatus  100 . 
     The information processing program is stored and provided as an installable or executable file in the storage medium  106  that can be read by the information processing apparatus  100  (computer) in which the information processing program is executed. The information processing program has a modular configuration including the above-described functional units. Each functional unit is generated on the RAM  103  as a result of the CPU  101  loading the program from the storage medium  106  and executing the loaded program. The information processing program may even be provided otherwise. Specifically, for example, the information processing program may be stored in a device connected to a network such as the Internet and provided by being downloaded via the communication IF  112  over the network. Specifically, in the information processing system  1000  according to the embodiment, the information processing apparatus  100  transmits an information processing program request to the computer program providing apparatus  300  to thereby download and install the information processing program from the computer program providing apparatus  300 . If the information processing program is updated after it has been installed, the updated information processing program is downloaded as follows. For example, the computer program providing apparatus  300  may notify the information processing apparatus  100  that the information processing program has been updated. This causes the information processing apparatus  100  to download and install the updated information processing program from the computer program providing apparatus  300 . Downloading of the updated information processing program may be the downloading of the program itself or differential elements that constitute the program, such as a library. The information processing program may still be embedded in advance and provided in the ROM  102  or the flash memory  104 , for example. 
     The following describes processing performed when the information processing program according to the embodiment is executed (cooperative operations of the functional units) using sequence diagrams and flowcharts. For convenience sake, the following description assumes an exemplary use situation in which the external display  200  is connected in advance and the information processing apparatus  100  is turned on. In addition, the following description assumes that the display control unit  11  and the scaling unit  12  are the functions achieved by modules to be started by the starting unit  21 . Additionally, the description will be given in two different patterns in terms of a difference in time until the completion of starting (hereinafter referred to as “starting time”) between the modules to be started. Specifically, in a first pattern, starting time A of the detection module is shorter than starting time B of the UI module. It is here noted that the detection module as used here is one of the modules that achieves the function of the display control unit  11  that detects the connection of the external display  200 . Thus, in the following, the starting time A of the detection module will be referred, for convenience sake, to as the starting time A of the display control unit  11 . Similarly, the UI module is one of the modules that achieves the function of the scaling unit  12  that generates the display screen corresponding to the external display  200 . Thus, in the following, the starting time B of the UI module will be referred, for convenience sake, to as the starting time B of the scaling unit  12 . Specifically, the scaling unit  12  takes longer time to complete starting than the display control unit  11  does. In a second pattern, the starting time of the display control unit  11  is longer than the starting time of the scaling unit  12 . Specifically, the scaling unit  12  takes shorter time to complete starting than the display control unit  11  does. 
     Processing performed when the starting time A of the display control unit  11  is shorter than the starting time B of the scaling unit  12   
       FIG. 4  is a sequence diagram illustrating exemplary processing procedure (part 1) at the time of the display control according to the embodiment. As illustrated in  FIG. 4 , when the information processing apparatus  100  according to the embodiment is turned on, the starting unit  21  detects that the information processing apparatus  100  has been turned on (step S 101 ) and requests the display control unit  11  and the scaling unit  12  to start (steps S 102   1 , S 102   2 ). It is noted that the exemplary processing procedure illustrates a case in which the starting unit  21  starts the functional units simultaneously. 
     Upon receipt of the requests, the display control unit  11  and the scaling unit  12  each start. Assume that the display control unit  11  thereafter completes starting earlier than the scaling unit  12  ([A&lt;B]). 
     The display control unit  11  that has completed starting earlier requests the information acquiring unit  22  to inquire about the device status of the external display  200  (step S 103 ). The information acquiring unit  22  sends a query about the device status to the external display  200  via the external display IF  118  (step S 104 ) and receives the device status notification from the external display  200  (step S 105 ). Thereby, the information acquiring unit  22  acquires the status information that indicates the connection status of the external display  200 . Based on the acquired status information, the information acquiring unit  22  responds to the display control unit  11  that made the request, regarding the device status of the external display  200  (step S 106 ). 
     Then, based on the device status response, the display control unit  11  changes over the display destination between the internal display  119  and the external display  200 . 
     Specifically, the display control unit  11 , having determined from the received device status response that the external display  200  is in a state where it can perform display, instructs the internal display  119  to turn off its display screen (step S 107 ). Next, the display control unit  11  accesses the registry  90  and writes the device status of the external display  200  based on the device status response (step S 108 ). The display control unit  11  thereby stores the device status of the external display  200  detected during the starting of the apparatus in the registry  90 , thus updating the default value of the device status information. Then, on completing writing the device status in the registry  90 , the display control unit  11  sends notification of a writing completion event to thereby notify the scaling unit  12  that the writing of the device status of the external display  200  is completed (step S 109 ). 
     On receipt of the writing completion event notification, the scaling unit  12  that has completed starting later than the display control unit  11  reads the device status information of the external display  200  from the registry  90  (steps S 110 , S 111 ). Specifically, the scaling unit  12  refers to the registry  90  and determines the device status according to the writing completion event notification. The scaling unit  12  thereby identifies, based on the read device status information, the external display  200  as the display destination after the changeover and performs the following scaling process. 
       FIG. 4  illustrates that the scaling unit  12  has completed starting at a point in time that the scaling unit  12  is notified of the writing completion event notification at step S 109 ; however, it is possible that the scaling unit  12  is yet to complete starting at that point in time. In such a case, the scaling unit  12 , because it is yet to complete starting, is unable to receive the writing completion event notification at step S 109 . After completing starting, however, the scaling unit  12  reads the device status information of the external display  200  from the registry  90  on its own initiative (steps S 110 , S 111 ). Specifically, the scaling unit  12  can refer to the registry  90  and determine the device status after the completion of starting without having to receive the writing completion event notification. 
     Based on the magnification obtained from the vertical length ratio and the horizontal length ratio of the display area of the internal display  119  and the display area of the external display  200 , the scaling unit  12  generates display data for scaling the display image displayed on the internal display  119  (step S 112 ). At this time, the scaling unit  12  generates the display data in which image data of the display image is embedded and the magnification value is set as the parameter value for the image scaling process in accordance with the specifications of the language that can be processed by the UI function of the external display  200 . Specifically, the scaling unit  12  generates the display data in which the value of an enlarging ratio is set as the parameter value for the image scaling process. Thereby, the scaling unit  12  enlarges the display image in accordance with the display area of the external display  200 . 
     The display control unit  11 , when having determined that the external display  200  is in a state where it can perform display, requests the information acquiring unit  22  to inquire about the device performance of the external display  200  (step S 113 ). The information acquiring unit  22  sends a query about the device performance to the external display  200  via the external display IF  118  (step S 114 ) and receives a device performance notification from the external display  200  (step S 115 ). The information acquiring unit  22  thereby acquires performance information from the external display  200 . Based on the acquired performance information, the information acquiring unit  22  responds to the display control unit  11  that made the request, regarding the device performance of the external display  200  (step S 116 ). 
     Having received the device performance response, the display control unit  11  instructs the setting unit  23  to set resolution in accordance with the screen specifications of the external display  200  based on the value of resolution included in the device performance response (step S 117 ). The setting unit  23  sets the resolution for the external display  200  based on the value of resolution received from the display control unit  11  (step S 118 ). In setting the resolution, the setting unit  23  sets the resolution based on the value of resolution included in the EDID of the external display  200 . 
     As a result, in the external display  200  selected as the display destination, the UI function interprets the display data and draws the scaled (enlarged) display image on the display screen. 
     As described heretofore, in the display control function according to the embodiment, even when the scaling unit  12  takes longer time to complete starting than the display control unit  11  does, the display destination is properly changed over based on the detection result of the external display  200 . 
     Processing performed when the starting time A of the display control unit  11  is longer than the starting time B of the scaling unit  12   
       FIG. 5  is a sequence diagram illustrating exemplary processing procedure (part 2) at the time of the display control according to the embodiment. As illustrated in  FIG. 5 , when the information processing apparatus  100  according to the embodiment is turned on, the starting unit  21  detects that the information processing apparatus  100  has been turned on (step S 201 ) and requests the display control unit  11  and the scaling unit  12  to start (steps S 202   1 , S 202   2 ). It is noted that the exemplary processing procedure illustrates a case in which the starting unit  21  starts the functional units simultaneously. 
     Upon receipt of the requests, the display control unit  11  and the scaling unit  12  each start. Assume that the display control unit  11  thereafter completes starting later than the scaling unit  12  ([A&gt;B]). 
     The scaling unit  12  that has completed starting earlier reads the device status information of the internal display  119  from the registry  90  (steps S 203 , S 204 ). The exemplary processing procedure illustrates that the display control unit  11  is still in the process of starting at this time, so that the device status information of the registry  90  is yet to be updated and is a default value. Thus, at this point in time, the scaling unit  12  reads the device status information of the internal display  119  stored as a default value in the registry  90 . 
     The display control unit  11  that has completed starting later than the scaling unit  12  requests the information acquiring unit  22  to inquire about the device status of the external display  200  (step S 205 ). The information acquiring unit  22  sends a query about the device status to the external display  200  via the external display IF  118  (step S 206 ) and receives a device status notification from the external display  200  (step S 207 ). The information acquiring unit  22  thereby acquires the status information that indicates the connection status of the external display  200 . Based on the acquired status information, the information acquiring unit  22  responds to the display control unit  11  that made the request, regarding the device status of the external display  200  (step S 208 ). 
     Then, based on the device status response, the display control unit  11  changes over the display destination between the internal display  119  and the external display  200 . 
     Specifically, the display control unit  11 , having determined from the received device status response that the external display  200  is in a state where it can perform display, instructs the internal display  119  to turn off its display screen (step S 209 ). Next, the display control unit  11  accesses the registry  90  and writes the device status of the external display  200  based on the device status response (step S 210 ). The display control unit  11  thereby stores the device status of the external display  200  detected during the starting of the apparatus in the registry  90 , thus updating the default value of the device status information. Then, on completing writing the device status in the registry  90 , the display control unit  11  sends notification of a writing completion event to thereby notify the scaling unit  12  that the writing of the device status of the external display  200  is completed (step S 211 ). 
     The scaling unit  12 , on receipt of the writing completion event notification, reads the device status information of the external display  200  from the registry  90  (steps S 212 , S 213 ). Specifically, the scaling unit  12  refers to the registry  90  and determines the updated device status according to the writing completion event notification. The scaling unit  12  thereby identifies the external display  200  as the display destination after the changeover based on the read device status information and performs the following scaling process. 
     Based on the magnification obtained from the vertical length ratio and the horizontal length ratio of the display area of the internal display  119  and the display area of the external display  200 , the scaling unit  12  generates display data for scaling the display image displayed on the internal display  119  (step S 214 ). At this time, the scaling unit  12  generates the display data in which image data of the display image is embedded and the magnification value is set as the parameter value for the image scaling process in accordance with the specifications of the language that can be processed by the UI function of the external display  200 . Specifically, the scaling unit  12  generates the display data in which the value of an enlarging ratio is set as the parameter value for the image scaling process. Thereby, the scaling unit  12  enlarges the display image in accordance with the display area of the external display  200 . 
     The display control unit  11 , when having determined that the external display  200  is in a state where it can perform display, requests the information acquiring unit  22  to inquire about the device performance of the external display  200  (step S 215 ). The information acquiring unit  22  sends a query about the device performance to the external display  200  via the external display IF  118  (step S 216 ) and receives a device performance notification from the external display  200  (step S 217 ). The information acquiring unit  22  thereby acquires performance information from the external display  200 . Based on the acquired performance information, the information acquiring unit  22  responds to the display control unit  11  that made the request, regarding the device performance of the external display  200  (step S 218 ). 
     Having received the device performance response, the display control unit  11  instructs the setting unit  23  to set resolution in accordance with the screen specifications of the external display  200  based on the value of resolution included in the device performance response (step S 219 ). The setting unit  23  sets the resolution for the external display  200  based on the value of resolution received from the display control unit  11  (step S 220 ). In setting the resolution, the setting unit  23  sets the resolution based on the value of resolution included in the EDID of the external display  200 . 
     As a result, in the external display  200  selected as the display destination, the UI function interprets the display data and draws the scaled (enlarged) display image on the display screen. 
     As described heretofore, in the display control function according to the embodiment, even when the scaling unit  12  takes shorter time to complete starting than the display control unit  11  does, the display destination is properly changed over based on the detection result of the external display  200 . 
     In addition, in the display control function according to the embodiment, the image displayed on the internal display  119  before the changeover is scaled (enlarged) to fit the size of the display area of the external display  200  after the changeover and displayed at an appropriate resolution. 
     Detailed processing when detecting the external display  200   
       FIG. 6  is a flowchart illustrating exemplary processing procedure when detecting the external display  200  according to the embodiment.  FIG. 6  illustrates exemplary detailed processing procedure performed for writing the device status information and sending notification of the writing completion event performed after the external display  200  has been detected. The exemplary processing is performed by the display control unit  11 . 
     As illustrated in  FIG. 6 , the display control unit  11  according to the embodiment uses the detection unit  11   a  to determine whether the connection of the external display  200  is detected (step S 11 ). 
     The display control unit  11 , when having determined that the connection of the external display  200  is detected (Yes at step S 11 ), writes the detected device status information of the external display  200  in the registry  90  (step S 12 ). At this time, the display control unit  11  writes the device status information based on the status response from the detected external display  200  in the registry  90 . Thereby, the display control unit  11  rewrites the default value of the device status information in the registry  90  (device status information of the internal display  119 ) with the device status information of the external display  200 , thus updating the default value of the device status information. 
     On completing writing the device status information in the registry  90 , the display control unit  11  notifies that the writing of the device status information of the detected external display  200  is completed (step S 13 ). At this time, the display control unit  11  notifies the scaling unit  12  of the writing completion event. 
     If it has determined that the connection of the external display  200  is not detected (No at step S 11 ), the display control unit  11  skips the processing of steps S 12  and S 13 . 
     Detailed Processing at the Time of Scaling 
       FIG. 7  is a flowchart illustrating exemplary processing procedure at the time of scaling according to the first embodiment.  FIG. 7  illustrates detailed scaling processing performed after the writing of the device status information of the external display  200  is completed. The exemplary processing is performed by the scaling unit  12 . 
     As illustrated in  FIG. 7 , the scaling unit  12  according to the embodiment determines whether a notification of the writing completion event indicating that the writing of the device status information in the registry  90  is completed is received (S 21 ). 
     The scaling unit  12 , when having determined that the writing completion event notification has been received (Yes at step S 21 ), refers to the registry  90  and reads the device status information (updated value) of the external display  200  stored in the registry  90  (step S 22 ). 
     Next, the scaling unit  12  performs the scaling processing corresponding to the external display  200  based on the read device status information (updated value) (step S 23 ). At this time, the scaling unit  12  identifies the external display  200  as the display destination after the changeover based on the read device status information and performs the scaling processing for the display image to make the display image correspond to the identified external display  200 . 
     If it has determined that the writing completion event notification is yet to be received (No at step S 21 ), the scaling unit  12  refers to the registry  90  and reads the device status information of the internal display  119  (default value) stored in the registry  90  (step S 24 ). 
     Next, the scaling unit  12  determines whether a predetermined period of time elapses after the device status information has been read (step S 25 ). This determining step assumes the following situation and is intended to select the internal display  119  as the display destination. For example, if the external display  200  that is preferentially selected as the display destination is not detected for some reason (including a situation in which the external display  200  cannot perform display) and if the writing completion event notification is not received within the predetermined period of time, the internal display  119  is selected as the display destination. The predetermined period of time represents a period of time required for performing this determining step (until the writing completion event is received) and may be set in advance in the information processing apparatus  100 . 
     Thus, as long as the scaling unit  12  determines that the predetermined period of time is yet to elapse after the device status information has been read (No at step S 25 ), the scaling unit  12  goes back to the step of step S 21  and comes to a state of waiting for the writing completion event notification to be received. 
     When having determined that the predetermined period of time elapses after the device status information has been read (Yes at step S 25 ), the scaling unit  12  performs the scaling processing corresponding to the internal display  119  based on the read device status information (default value) (step S 26 ). At this time, the scaling unit  12  identifies the internal display  119  as the display destination after the changeover based on the read device status information and performs the scaling processing for the display image to make the display image correspond to the identified internal display  119 . 
     OVERVIEW 
     As described above, the information processing apparatus  100  according to the embodiment detects the connection status of the external display  200 . Based on the detected connection status, the information processing apparatus  100  changes over the display destination between the internal display  119  and the external display  200  and controls the display screen according to the screen specifications of the display corresponding to the display destination after the changeover. At this time, in the information processing apparatus  100 , the detection module stores the detected connection status of the external display  200  and notifies the UI module that writing is completed. When the UI module receives the notification of the completion of writing, the information processing apparatus  100  acquires the connection status of the stored external display  200 ; and, based on the acquired information, scales the display image and sets resolution corresponding to the external display  200 . 
     The information processing apparatus  100  according to the embodiment thereby provide an environment in which the display destination is changed over properly based on the result of detection of the external display  200 , regardless of the order in which the modules start. As a result, the information processing apparatus  100  according to the embodiment can properly change over the display destination even during starting of the display control function. 
     The embodiment has been described for a case in which the device status information is stored in the registry  90 . This is, however, not the only possible arrangement. The area in which the device status information is stored may be any predetermined area as long as the area can be accessed by the detection module (the display control unit  11 ) that writes the information and the UI module (the scaling unit  12 ) that reads the information. 
     The embodiment has been described for a case in which the display control is performed for the display devices. This is, however, not the only possible arrangement. The display control may be performed for, for example, a PC, a smartphone, a tablet terminal, or a portable telephone. Specifically, the display control may be performed for any device as long as it can be connected to the information processing apparatus  100  and has a display. 
     The embodiment has been described for a case in which the functions of the information processing apparatus  100  are achieved by the software implemented therein. This is, however, not the only possible arrangement. For example, part or all of the functional units of the information processing apparatus  100  may even be achieved by hardware mounted therein. 
     In addition, the embodiment has been described for a case in which the conference material saved in the information processing apparatus  100  is displayed on the internal display  119  or the external display  200  in the conference service. This is, however, not the only possible arrangement. For example, an external device may be connected to the information processing apparatus  100  and the conference material may be displayed on the internal display  119  or the external display  200  from the external device, the information processing apparatus  100  receives display data for displaying reference data. 
     The embodiment provides an advantageous effect of enabling a proper changeover of the display even during starting of the display control function. 
     Although the invention has been described with respect to specific embodiments for a complete and clear disclosure, the appended claims are not to be thus limited but are to be construed as embodying all modifications and alternative constructions that may occur to one skilled in the art that fairly fall within the basic teaching herein set forth.
A computer program product includes a non-transitory computer-usable medium having computer-readable program codes embodied in the medium. The program codes when executed cause a computer to execute: detecting a connection status of an externally connected second display different from a built-in first display; writing status information indicating the detected connection status in a storage, changing over a display destination between the first display and the second display based on the detected connection status, and controlling a display screen according to screen specifications of the first display or the second display, which corresponds to the display destination after changeover; and reading the connection status written in the storage and scaling a display image at a magnification based on the read connection status.