Patent Application
20120013628
The present invention relates to an information processing apparatus such as a personal computer, and more particularly, relates to an information processing apparatus capable of outputting a video signal to an external display such as a projector.
JP2005-257948A (hereinafter referred to as Patent Document 1) describes a personal computer (PC) that can output a video signal to a projector. This personal computer includes a layer capture part, a display output part, a display image generation part, a PC communication part and a control part.
The display image generation part generates a display image formed from a plurality of layers. The display output part displays a display image generated by the display image generation part. The control part retains information on a layer to be transmitted to the projector, and, based on the information, indicates to the layer capture part a layer to be transmitted.
The layer capture part captures a layer to be transmitted from among layers forming the display image generated by the display image generation part in accordance with an indication from the control part. The PC communication part transmits the layer captured by the layer capture part to the projector that is an external device. The projector displays a screen based on the layer captured at the layer capture part.
According to the personal computer, only the layer that is specified in advance is transmitted to the projector. Namely, among screens displayed on the personal computer side, information on a screen (tool screen and the like) that is not necessary to be displayed on the projector side is not transmitted to the projector.
Therefore, when an explanation of materials is made at a meeting or the like using a system in which the projector is connected to the personal computer, only screens necessary for participants can be displayed on the projection screen of the projector.
However, in the personal computer of Patent Document 1, a process, in which a layer that is specified in advance (layer to be transmitted to the projector) is sorted out from an image formed from a plurality of layers, and then the sorted layer is captured, is performed through a CPU (Central Processer Unit). Thus, sorting and capture processing increase the load on the CPU.
It is an object of the present invention to provide an information processing apparatus, an image display control method and program capable of reducing the processing load on a CPU without outputting to an external display, screen information that is not necessary to be displayed on the external display.
To achieve the above object, an information processing apparatus according to an aspect of the present invention includes:
first and second memories;
a DMA controller that periodically performs a data transfer from the first memory to the second memory;
a display that displays an image based on a video signal output from the first memory;
a video output terminal that outputs a video signal output from the second memory to an external device; and
a controller that, when executing a specific application, prohibits the screen information related to the specific application from being transferred by the DMA controller, and then writes the screen information into the first memory.
An information processing apparatus according to another aspect of the present invention includes:
first and second memories;
a DMA controller that performs a data transfer from the first memory to the second memory;
a display that displays an image based on a video signal output from the first memory;
a video output terminal that outputs a video signal output from the second memory to an external device; and
a controller that writes screen information to be displayed on the display into the first memory, and periodically updates the written screen information, while at the same time controlling the DMA controller to periodically perform a data transfer, wherein
when executing a specific application, the controller writes screen information related to the specific application into the first memory, thereafter, if causing the DMA controller to perform a data transfer, deletes the screen information related to the specific application from the first memory, updates screen information other than the deleted screen information, causes the screen information that has been updated to be transferred from the first memory to the second memory, and after the transfer is completed, rewrites the screen information related to the specific application into the first memory.
A screen display control method according to an aspect of the present invention includes:
periodically performing a data transfer from a first memory to a second memory by DMA control, while at the same time displaying an image based on a video signal output from the first memory on a display, and supplying a video signal output from the second memory to a video output terminal to which an external device is connected, and
when executing a specific application, prohibiting screen information related to the specific application from being transferred by the DMA control, and then writing the screen information into the first memory.
A screen display control method according to another aspect of the present invention
which is performed at an information processing apparatus including first and second memories, a display that displays an image based on a video signal output from the first memory, and a video output terminal that outputs a video signal output from the second memory to an external device, includes:
writing screen information to be displayed on the display into the first memory, and periodically updating the written screen information, while at the same time periodically performing a data transfer from the first memory to the second memory by DMA control, and
when executing a specific application, writing screen information related to the specific application into the first memory, thereafter, if performing a data transfer by DMA control, deleting the screen information related to the specific application from the first memory, updating screen information other than the deleted screen information, causing the screen information that has been updated to be transferred from the first memory to the second memory, and after the transfer is completed, rewriting the screen information related to the specific application into the first memory.
A program according to an aspect of the present invention causes a computer to execute processes of:
periodically transferring screen information stored in a first memory to a second memory by DMA control, while at the same time displaying an image based on a video signal output from the first memory on a display, and supplying a video signal output from the second memory to a video output terminal to which an external device is connected, and
when executing a specific application, prohibiting screen information related to the specific application from being transferred by the DMA control, and then writing the screen information into the first memory.
A program according to another aspect of the present invention is a program for use in an information processing apparatus including first and second memories, a display that displays an image based on a video signal output from the first memory, and a video output terminal that outputs a video signal output from the second memory to an external device, the program causing a computer of the information processing apparatus to execute processes of:
writing screen information to be displayed on the display into the first memory, and periodically updating the written screen information, while at the same time periodically performing a data transfer from the first memory to the second memory by DMA control, and
when executing a specific application, writing the screen information related to the specific application into the first memory, thereafter, if a data transfer is performed by the DMA control, deleting the screen information related to the specific application from the first memory, updating screen information other than the deleted screen information, causing the screen information that has been updated to be transferred from the first memory to the second memory, and after the transfer is completed, rewriting the screen information related to the specific application into the first memory.
Next, exemplary embodiments of the present invention will be described with reference to the drawings.
Referring to
Controller 10, memory 11, input operation part 12, primary VRAM 13, secondary VRAM 14, selector 15 and DMA controller 19 are each connected to bus 18. Display 16 is comprised of a display device such as a liquid crystal display. Video output terminal 17 outputs a video signal to an external display such as a projector. An address in a memory space of primary VRAM 13 corresponds in a one-to-one fashion to an address in a memory space of secondary VRAM 14.
Programs necessary to operate the information processing apparatus, various applications and data are stored in memory 11. An application related to a GUI and display screen information therefor are also stored in memory 11. The application related to a GUI includes a specific application (tool) to remotely control a projector.
Selector 15 includes first and second input ports, and first and second output ports. The output signal from primary VRAM 13 is supplied to the first input port of selector 15. The output signal from secondary VRAM 14 is supplied to the second input port of selector 15.
DMA controller 19 controls a data transfer from primary VRAM 13 to secondary VRAM 14. Specifically, DMA controller 19 includes table 20 in which address information indicating a data range for primary VRAM 13 to perform a transfer is stored, and refers to table 20 to copy (draw) screen information from primary VRAM 13 to secondary VRAM 14. The drawing by DMA controller 19 is performed at regular intervals. In table 20, address information specifying the entire address space of primary VRAM 13 as a data range to which a transfer is to be performed is stored as the default value.
In addition, when address information indicating a copy-prohibited range is stored in table 20, DMA controller 19 performs no data transfer from primary VRAM 13 to secondary VRAM 14 for the copy-prohibited range. Namely, DMA controller 19 transfers screen information that is not included in the copy-prohibited range from primary VRAM 13 to secondary VRAM 14.
In selector 15, in accordance with a switching signal from controller 10, switching is performed between a first state in which the first input port is connected to the first and second output ports and a second state in which the first input port is connected to the first output port and the second input port is connected to the second output port.
Input operation part 12 includes a pointing device typified by a mouse and the like, and a keyboard. A user uses input operation part 12 to perform input indication indicating that the information processing apparatus is to be operated.
Controller 10 controls the operation of the entire information processing apparatus in accordance with a program stored in memory 11. At startup of the information processing apparatus, controller 10 supplies to selector 15 a switching signal indicating that the first state is to be selected. At the same time, controller 10 acquires from memory 11 information on the bottommost layer screen of the GUI, that is, desktop screen information that is displayed at startup, and writes the acquired screen information into primary VRAM 13.
In addition, when accepting from input operation part 12 an input indication indicating that a specific application is to be executed, controller 10 executes the specific application, and supplies to the selector 15 the switching signal indicating that the second state is to be selected. At the same time, controller 10 acquires from memory 11 screen information corresponding to the specific application that has been executed, prohibits DMA controller 19 from transferring the acquired screen information, and then overwrites the screen information onto primary VRAM 13. In transfer prohibition processing, the screen information acquired from memory 11 includes address information that is to be the write destination, and controller 10 writes the address information into table 20 of DMA controller 19 as a copy-prohibited range.
Next, screen display control processing of the information processing apparatus of the present exemplary embodiment will be described.
When the information processing apparatus is activated (step S 10), controller 10 supplies to selector 15 a switching signal indicating that the first state is to be selected (step S11), while at the same time acquiring from memory 11 desktop screen information and writing the acquired screen information into primary VRAM 13 (step S12).
Next, DMA controller 19 refers to table 20 (default) to copy (draw) the screen information from primary VRAM 13 to secondary VRAM 14 (step S13). Thereafter, the output signal from primary VRAM 13 is supplied to display 16 and video output terminal 17 through selector 15 (step S14). In this case, the same screen information is displayed on both display 16 and the projector to which video output terminal 17 is connected.
After the screen information is displayed, controller 10 accepts the input from input operation part 12 and performs necessary processing (step S15).
Next, controller 10 determines whether or not an input indication, from input operation part 12, indicating that a specific application is to be executed, has been accepted (step S16). If an input indication is accepted, controller 10 executes the specific application, and supplies to selector 15 a switching signal indicating that the second state is to be selected. At the same time, controller 10 acquires from memory 11 screen information related to the specific application that has been executed, prohibits DMA controller 19 from transferring the acquired screen information, and then overwrites the acquired screen information onto primary VRAM 13 (step S18).
Next, DMA controller 19 refers to table 20 to copy (draw) screen information that is not included in the copy-prohibited range from primary VRAM 13 to secondary VRAM 14 (step S19). Thereafter, an output signal from primary VRAM 13 is supplied to display 16 through selector 15, and an output signal from secondary VRAM 14 is supplied to video output terminal 17 through selector 15 (step S20). In this case, although a screen including a GUI screen related to the specific application that has been executed is displayed on display 16, screens except for the GUI screen are displayed on the projector connected to video output terminal 17.
After the screen information is displayed, controller 10 accepts the input from input operation part 12 and performs necessary processing (step S21).
Next, controller 10 determines whether or not the input indication, from input operation part 12, indicating that the specific application is to be completed, has been accepted (step S22). If an input indication is accepted, controller 10 supplies to selector 15 a switching signal indicating that the first state is to be selected, while at the same time deleting from table 20 address information of the copy-prohibited range related to the specific application (step S23). Then, the procedure proceeds to processing of step S15.
The information processing apparatus of the present exemplary embodiment that has been described produces the following effects.
When processing of steps S10 to S15 shown in
When processing of steps S16 to S21 shown in
The specific application is a tool (software) to remotely control projector 22, for example.
A plurality of operation buttons are disposed on the GUI screen shown in
As described above, according to the information processing apparatus of the present exemplary embodiment, when an explanation of materials is made at a meeting or the like using a system shown in
In addition, according to the information processing apparatus of the present exemplary embodiment, the copying (drawing) of screen information from primary VRAM 13 to secondary VRAM 14 is performed by DMA control, and controller 10 only prohibits the DMA transfer of screen information related to the specific application when the specific application is executed. Accordingly, the processing load on the CPU can be reduced by not outputting unnecessary screen information to an external display.
Basically, processing performed by controller 10 can be provided by a program. The program may be provided to a user via a storage medium such as a CD-ROM and a DVD, or through a network typified by the Internet. In addition, a program that can perform processing of steps S16 to S23 shown in
Note that in the information processing apparatus shown in
Referring to
Screen information is stored in memories 31 and 32. Display 34 displays an image based on a video signal output from memory 31. Video output terminal 35 is a video output terminal for outputting a video signal output from memory 32 to an external device. DMA controller 33 periodically transfers screen information stored in memory 31 to memory 32. When executing a specific application, controller 30 prohibits the screen information related to the specific application from being transferred by DMA controller 33, and then writes the screen information into memory 31.
The present exemplary embodiment also produces similar effects to those of the information processing apparatus of the first exemplary embodiment.
In addition, also in the present exemplary embodiment, processing related to the screen display control by controller 30 is provided by a program. The program may be provided to a user via a storage medium such as a CD-ROM and a DVD, or through a network typified by the Internet. For example, a program is provided that causes a computer to perform a processing operation for periodically transferring screen information stored in the first memory to the second memory by DMA control, while at the same time displaying on a display an image based on a video signal output from the first memory, and supplying a video signal output from the second memory to a video output terminal to which an external device is connected, and the processing of, when executing a specific application, prohibiting the screen information related to the specific application from being transferred by the DMA control, and then writing the screen information into the first memory.
In the information processing apparatus of the first and second exemplary embodiments, screen information (static image), which has been displayed before a specific application is executed, is displayed on the area corresponding to screen information 21b on projection screen 22a of projector 22 in a screen display form shown in
The information processing apparatus of the other exemplary embodiment has basically the same configuration as that shown in
When an application for moving image is executed, controller 30 writes screen information related to the application into memory 31. In this case, since the image information is a moving image, writing of image information by controller 30 is performed on a frame basis.
When executing a specific application, controller 30 writes the screen information related to the specific application into memory 31. Then, controller 30 deletes the screen information related to the specific application written into memory 31. After the deletion, controller 30 supplies a data transfer indication signal to DMA controller 33 before the screen information for the next moving image (one frame) is written into memory 31.
DMA controller 33 starts performing a data transfer from memory 31 to memory 32 in accordance with a data transfer indication from controller 30. After the data transfer is completed, DMA controller 33 supplies to controller 30 a data transfer completion signal indicating that the data transfer has been completed.
When receiving the data transfer completion signal from DMA controller 33, controller 30 rewrites the screen information related to the specific application into memory 31.
In
In the update of screen information in memory 31, update processing is performed for the overlapping portion based on a priority order referred to as Z order. Specifically, if a plurality of screens are overlapped, the ordering is such that the priority of the screen situated in the foreground is the highest, and the priority of the screen situated in the background is the lowest. The screen with a higher-priority is updated earlier, and for the screen with a lower-priority, the area of the screen other than the overlapping portion is updated. In the example shown in
After writing screen information for moving image (one frame) into area 41 in memory 31, controller 30 overwrites the screen information related to the specific application into area 40 in memory 31 (see the second image from the left in
After deleting the screen information related to the specific application, controller 30 supplies a data transfer indication signal to DMA controller 33 before the screen information for the next moving image (one frame) is written into memory 31. DMA controller 33 starts performing a data transfer from memory 31 to memory 32 in accordance with a data transfer indication from controller 30. According to this data transfer, the screen information of area 41 in memory 31, which has been updated, is transferred to area 42 in memory 32 (see the fourth image from the left in
After data transfer has been completed, DMA controller 33 supplies to controller 30 a data transfer completion signal indicating that the data transfer has been completed. When receiving the data transfer completion signal from DMA controller 33, controller 30 rewrites the screen information related to the specific application into area 40 in memory 31. Thus, the sequence of screen information according to Z order is reset again in memory 31. As a result, in area 41, screen information is not updated for the portion overlapping with area 40, and updating of screen information (frame-by-frame update) is performed for the other portions.
The period required for transferring data by DMA controller 33 is longer than the period required for updating screen information of area 41 in memory 31. Since the display period of the screen information in the projector is determined according to the data transfer period, it is desirable that the data transfer period be shortened as much as possible.
The above processing may also be applied to the information processing apparatus shown in
The information processing apparatus of the other exemplary embodiment also produces similar effects to those of the first and second exemplary embodiment. In addition, according to the information processing apparatus of the other exemplary embodiments, screen information can be also updated for the area corresponding to screen information 21b on projection screen 22a of projector 22 in the screen display form shown in
Also in the other exemplary embodiment, processing related to the screen display control by controller 30 is provided by a program. The program may be provided to a user via a storage medium such as a CD-ROM and a DVD, or through a network typified by the Internet. For example, there is provided a program which is used in an information processing apparatus including first and second memories, a display that displays an image based on a video signal output from the first memory, and a video output terminal that outputs a video signal output from the second memory to an external device. This program causes a computer of the information processing apparatus to perform a processing operation for: writing screen information to be displayed on the display into the first memory, and periodically updating the written screen information, while at the same time periodically performing a data transfer from the first memory to the second memory by DMA control, and when executing a specific application, writing screen information related to the specific application into the first memory, thereafter, if a data transfer is performed by the DMA control, deleting the screen information related to the specific application from the first memory, updating the screen information other than the deleted screen information, causing the screen information that has been updated to be transferred from the first memory to the second memory, and after the transfer has been completed, rewriting the screen information related to the specific application into the first memory.
Each exemplary embodiment that has been described above is an example of the present invention, and the configuration and operation thereof may be changed without departing from the spirit of the present invention.
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/JP2009/056639 | 3/31/2009 | WO | 00 | 9/22/2011 |
