Display image updating system

【0001】

[Technical field to which the invention belongs]

The present invention relates to a display screen update system for an information processing device, and in particular, transmits the display screen of the information processing device to a remote display terminal device connected via a communication line, and displays the display screen of the information processing device on the display terminal device side. Related to the display screen update system of the information processing device that displays.

【0002】

[Conventional technology]

In recent years, with the development of mobile communication such as mobile phones and wireless LANs, mobile computing using portable terminal devices such as notebook personal computers and PDAs has been actively performed. There is an increasing demand for operating an information processing device such as a personal computer located at a remote location such as a company or home to browse the screen of the information processing device.

【0003】

Conventionally, a remote display screen update system for an information processing device using a communication line such as a telephone line or a network has been used, for example, VNC (Virtual Network). There is a remote display screen update system for information processing devices that uses the Computing) method. Fig. 23 shows the overall configuration of the remote display screen update system of the conventional information processing device using the VNC method. The information processing device 301 and the remote display terminal device 302 are connected via a communication line 303. In this remote display screen update system of the conventional information processing device, the conventional information processing device includes a CPU 304 which is a control device and a main memory 305 which stores various data processed by the CPU 304 and a program indicating a processing procedure. Similarly, a large-capacity storage device 306 such as a hard disk that records various data and programs, a display buffer 307 that stores pixel data of the display screen, and a screen data processing and information processing device according to control commands from the CPU 304. The information processing device 301 is composed of a video controller 308 that displays on the display device of the above, a communication device 309 that communicates with the remote display terminal device 302, and an input device 310 for inputting an operation from the user. The display screen to be drawn is displayed on the remote display terminal device 302. On the information processing device 301, the operation system and various application programs stored in the main memory 305 and the large-capacity storage device 306 are executed by the CPU 304, and each application program issues a drawing instruction, and the CPU 304 follows the instruction. And the video controller 308 are drawing the display screen in the display buffer 307.

【0004】

Next, in the remote display screen update system of the conventional information processing device using VNC, the drawing command issued by each application program is monitored, the transmission area candidate of the display screen is extracted, and the transmission area candidate of the extracted display screen is extracted. To integrate. Next, the pixel data of the integrated transmission area candidate is read from the display buffer 307, the value of the read pixel data is compared with the value of the pixel data transmitted to the display terminal device last time, and the update screen area changed from the previous time is determined. .. Next, the display screen of the information processing device 301 is transmitted by reading the pixel data of the determined update screen area from the display buffer 307, losslessly compressing the pixel data, and transmitting the pixel data from the communication device 309 to the remote display terminal device. Has been realized.

【0005】

In addition, as a remote display screen update system for other conventional information processing devices, as in JP-A-8-297617, only drawing commands are extracted from commands issued by application programs, and the drawing commands are transmitted to the communication line. A remote display device for a computer that transmits to a remote display terminal device via a remote display terminal device and transmits the display screen of the computer to the remote display terminal device by executing a received drawing command has also been proposed. There is.

【0006】

[Problems to be Solved by the Invention]

However, in the remote display screen update system of the conventional information processing device by the VNC method, all the processes such as extraction of the transmission candidate area, reading of the pixel data of the transmission candidate area, and comparison of the pixel data are performed by the CPU, so that information processing is performed. The load on the device is very heavy, and the load is high even if the screen is not updated. In addition, since it takes time from the extraction of the transmission candidate area to the determination of the update screen area, it is not possible to quickly respond to the screen changing at high speed. Also, in order to extract the display screen data to be transmitted from the display buffer, a drawing command that does not write pixel data directly to the display buffer that uses the acceleration function of the video controller (for example, Direct of WINDOWS). The display screen drawn by Draw) cannot be supported because there is no pixel data in the display buffer. In addition, the drawing screen of the information processing device is often required to be faithfully reproduced even on the remote display terminal device side, and blurring and distortion are often not allowed. Therefore, all the updated screens are reversibly compressed. Screen data by updating the screen so that the user can visually recognize not necessarily necessary screen data such as data due to screen update that the user cannot visually recognize and data in the screen area that is not being watched. Since screen data that should be transmitted preferentially is also transmitted under the same conditions, data transmission and data processing that are originally unnecessary for the user have been performed.

【0007】

Further, in the remote display device of the computer according to Japanese Patent Application Laid-Open No. 8-297617, the drawing command processed on the information processing device side is transmitted as it is to the remote display terminal device to update the display screen, so that the display screen can be quickly displayed. In order to update, the remote display terminal device needs to have a drawing processing capacity equal to or higher than that of the information processing device to be operated, and the remote display terminal device may be a terminal device having a low drawing processing capacity such as a mobile terminal device. For example, the display screen cannot be updated quickly.

【0008】

Therefore, an object of the present invention is to reduce the load on the CPU of the information processing device that transmits the display screen in the remote display screen update system of the information processing device, and to quickly update the display screen of the remote display terminal device. , It is possible to update the display screen by any drawing command, reduce the amount of data to be transmitted without the user feeling visually uncomfortable, and the remote display terminal device is, for example, a portable device that requires low power consumption. Even when the drawing processing capacity of a terminal device is inferior to that of the information processing device, the display screen of the information processing device can be updated quickly.

【0009】

[Means for solving problems]

In order to solve the above-mentioned conventional problems, the first invention (corresponding to claim 1) is a display screen update system for transmitting a display screen to a display terminal device, which is a video controller and a display output from the video controller. An update that extracts the presence or absence of an update by comparing the data of the two frames stored in the actual display screen frame storage means that stores the data for two frames of the screen and the actual display screen frame storage means in a predetermined rectangular area unit. The rectangular area extraction means, the flag table for recording the flag based on the presence or absence of the update extracted by the update rectangular area extraction means, and the screen area to be transmitted to the display terminal device are determined based on the flag recorded in the flag table. A predetermined compression process is performed on the transmission screen area determining means, the transmission screen data extracting means for extracting the pixel data of the transmission screen area determined by the transmission screen area determining means, and the transmission screen data extracted by the transmission screen data extracting means. This is a display screen update system including an image compression means for performing the above and a communication means for transmitting the transmission screen data compressed by the image compression means to the display terminal device.

【0010】

The second invention (corresponding to claim 2) is a display screen update system for transmitting a display screen to a display terminal device, which is data for two frames of a video controller and a display screen output from the video controller. At the same time as the output recording of the frame data from the video controller to the actual display screen frame storage means and the actual display screen frame storage means for storing the output recording data and the previous frame recorded in the actual display screen frame storage means. Data comparison is performed in units of predetermined rectangular areas to extract the presence or absence of update, a flag table for recording a flag based on the presence or absence of update extracted by the update rectangular area extraction means, and the flag table. A transmission screen area determining means for determining a screen area to be transmitted to the display terminal device based on the flag recorded in, and a transmission screen data extracting means for extracting pixel data of the transmission screen area determined by the transmission screen area determining means. An image compression means that performs a predetermined compression process on the transmission screen data extracted by the transmission screen data extraction means, and a communication means that transmits the transmission screen data compressed by the image compression means to the display terminal device. It is a display screen update system characterized by the fact that.

【0011】

The third invention (corresponding to claim 3) is the first invention to be characterized in that the actual display screen frame storage means is composed of two or more memories, and the memory to be stored is changed for each frame. The display screen update system according to any one of the second inventions.

【0012】

Further, in the fourth invention (corresponding to claim 4), the transmission screen data extracting means extracts pixel data of a transmission screen area determined by the transmission screen area determining means from the actual display screen frame storage means. The display screen update system according to any one of the first invention to the second invention.

【0013】

Further, the fifth invention (corresponding to claim 5) stores the number of frame intervals for determining the frame interval to be recorded in the actual display screen frame storage means, and the actual display screen frame storage means for each frame interval number. The display screen update system according to any one of the first and second inventions, characterized in that the frame storage rate control means for controlling the recording of frame data is provided.

【0014】

Further, the sixth invention (corresponding to claim 6) detects the number of updates in which the display screen is updated for each predetermined period or for each predetermined frame occurrence count period, and stores the frame based on the update count. The display screen update system according to the fifth aspect of the present invention, which comprises a display screen update count detecting means for setting the number of frame intervals of the rate control means.

【0015】

Further, the seventh invention (corresponding to claim 7) detects the remaining amount of the transmission buffer of the communication means, and based on the remaining amount of the buffer, the frame of the frame storage rate control means is based on the number of updates. The display screen update system according to the fifth aspect of the present invention, which comprises a transmission buffer remaining amount detecting means for setting the number of intervals.

【0016】

The eighth invention (corresponding to claim 8) is the first invention to the second, wherein the update rectangular area extraction means extracts the presence or absence of update depending on whether or not the difference between the screens is a certain value or more. The display screen update system according to any one of the inventions.

【0017】

Further, the ninth invention (corresponding to claim 9) is characterized in that the updated rectangular area extraction means has an update when the difference between the pixels in the predetermined rectangular area is equal to or more than a predetermined value even if it is one pixel. This is a display screen update system according to the eighth aspect of the invention.

【0018】

Further, the tenth invention (corresponding to claim 10) is characterized in that the updated rectangular area extraction means has an update when the number of detected differences in pixels in a predetermined rectangular area is equal to or greater than a predetermined value. This is a display screen update system according to the eighth aspect of the present invention.

【0019】

Further, in the eleventh invention (corresponding to claim 11), the updated rectangular region extraction means converts the pixel data of a predetermined rectangular region into frequency components, and if there is a difference in the components of the predetermined frequency, the update is available. It is a display screen update system according to the eighth aspect of the invention.

【0020】

Further, in the twelfth invention (corresponding to claim 12), the updated rectangular area extraction means performs data comparison in units of predetermined rectangular areas to determine whether there is a difference required for transmission and whether there is a difference less than the difference required for transmission. Extracted, the flag table records a flag based on the presence or absence of a difference required for transmission and a flag based on the presence or absence of a difference less than the difference required for transmission, and the transmission screen area determining means transmits based on the output of the flag table. The rectangular area corresponding to the flag having the required difference is determined as the transmission screen area, and the rectangular area corresponding to the flag having the difference less than the required difference is determined as the transmission screen area at predetermined time intervals. The display screen update system according to any one of the first invention to the second invention.

【0021】

Further, in the thirteenth invention (corresponding to claim 13), the updated rectangular area extraction means performs data comparison in units of predetermined rectangular areas to extract the presence or absence of a difference that requires transmission and the presence or absence of a difference that does not require transmission. The flag table records a flag based on the presence or absence of a difference required for transmission and a flag based on the presence or absence of a difference less than the difference required for transmission, and the transmission screen area determining means records a difference required for transmission based on the output of the flag table. The rectangular area corresponding to the flag having is determined as the transmission screen area, and the rectangular area corresponding to the flag having a difference less than the required difference for transmission is set as the transmission screen area when the number of occurrences of the flag exceeds a predetermined number. The display screen update system according to any one of the first invention to the second invention, which comprises determining.

【0022】

Further, the fourteenth invention (corresponding to claim 14) has an area priority setting means for setting a priority for each divided screen area, and is based on the priority set by the area priority setting means. The display screen update system according to any one of the first and second inventions, characterized in that the update time interval for each screen area is determined.

【0023】

Further, the fifteenth invention (corresponding to claim 15) counts the number of times the flag with update of the flag table has occurred, and the display screen is composed of a plurality of rectangular areas according to the number of times of counting. The display screen update system according to the fourteenth aspect of the present invention, which comprises a flag update number counting means for dividing into a screen area and setting a priority in the area priority setting means.

【0024】

Further, the 16th invention (corresponding to claim 16) is an application program display position detecting means for detecting an operating application program and detecting a screen area, and an application program for storing the characteristics of the screen drawn by the application program. It has a drawing screen characteristic table, and priorities are set in the area priority setting means based on the screen area detected by the application program display position detecting means and the characteristics of the screen stored in the application program drawing screen characteristic table. It is a display screen update system according to the fourteenth invention.

【0025】

Further, the seventeenth invention (corresponding to claim 17) has a region-specific compression method selection means for setting a compression method for each divided screen area, and the image compression means is the region-specific compression method selection means. The display screen update system according to any one of the first and second inventions, characterized in that a predetermined compression process is applied to transmission screen data based on a selected compression method.

【0026】

BEST MODE FOR CARRYING OUT THE INVENTION

(Embodiment 1) Embodiment 1 of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the overall configuration of the first embodiment of the remote display screen update system of the information processing device, and shows its own display screen on the display terminal device 2 that displays the display screen remotely and the remote display terminal device 2. It is composed of a communication line 3 connecting an information processing device 1 for transmitting information, an information processing device 1 and a display terminal device 2.

【0027】

Here, the information processing device 1 sets the frame data of the CPU 4, the main memory 5, the large-capacity storage device 6, the communication device 9, the video controller 8, the display buffer 7, the input device 10, the image compression device 11, and the display screen in frame units. It is composed of a memory A12 and a memory B13 which are storage means for storing actual display frames, a memory switching control circuit 14, an update rectangular area extraction circuit 15, and a flag table 16.

【0028】

The main memory 5 is a semiconductor RAM or ROM for storing operation system programs and various application programs, the large-capacity storage device 6 is a hard disk, a CD-ROM device, etc., and the input device 10 is a user such as a keyboard or mouse. Is a device for inputting operations, and a communication device 9 is a device for communicating with a display terminal device such as a modem, LAN, or wireless LAN.

【0029】

The CPU 4 controls the information processing device 1 according to the instructions of the operation system program and various application programs recorded in the main memory 5 and the large-capacity storage device 6, and displays the screen data according to the instructions of these various programs. It is a control device that writes to the display buffer 7 at any time.

【0030】

The video controller 8 is a device that processes screen data of the display screen according to a command from the CPU 4 and outputs a frame control signal and frame data of the display screen in order to display the display screen on the display device.

【0031】

The image compression device 11 is a device that compresses screen data to be transmitted, and since the screen of an information processing device generally has many still images and accuracy of display contents is often required, lossless compression such as Huffman coding or the like is performed. Is used. Here, the image compression device 11 may use a dedicated hardware circuit, or may be configured to record an application program in the main memory 5 or the large-capacity storage device 6 and process it by the CPU 4. ..

【0032】

Further, the memory A12 and the memory B13 are actual display frame storage means for storing the frame data of the display screen output from the video controller 8, and are frame control signals (for example, vertical synchronization signals) output from the video controller 8. According to this, the memory switching control circuit 14 alternately switches the memory A12 and the memory B13 in frame units, and stores the frame data of the display screen output from the video controller 8 at the pixel clock rate.

【0033】

The update rectangular area extraction circuit 15 detects the vertical non-display section by the frame control signal, reads out the frame data of the display screen of the front and rear frames stored in the memory A12 and the memory B13 pixel by pixel, compares them, and makes a difference. Is detected, it is reflected in the flag corresponding to the pixel with the difference in the flag table 16.

【0034】

FIG. 2 is a diagram showing the relationship between the flag and the display screen. One flag is assigned to each rectangular area obtained by dividing the display screen area by a predetermined rectangular area. For example, as shown in FIG. 2, one flag is assigned to the rectangular area 21 of 8 × 8 pixels. 22 is assigned to flag table 16. The flag table 16 can be read from the CPU 4 via the system bus I / F (interface) 17, and the CPU 4 can know which area should be sent by looking at which flag in the flag table 16 is set. In the example of FIG. 2, one flag is associated with a rectangular area of 8 × 8 pixels, but the size of the rectangular area corresponding to one flag may be 16 × 16 pixels or 16 × 8 pixels. , Not limited to this.

【0035】

Next, the operation of the remote display screen update system of the information processing device of the first embodiment will be described. FIG. 3 is a flowchart showing the processing of the information processing apparatus according to the first embodiment.

【0036】

First, when the display screen request is received from the connected display terminal device 2, the process is started, and in step S101, the acquisition of the frame data of the display screen in units of one frame is started from the video controller. Next, in step S102, all the data of the display screen recorded in the display buffer is extracted. Next, in step S103, the extracted display screen data is compressed by the image compression device 11 and sent to the communication device 9. In step S104, the compressed display screen data received by the communication device is transmitted to the display terminal device. Next, in step S105, the update rectangular area extraction circuit 15 compares the frame data of the display screen stored in the memory A12 and the memory B13, waits for the update rectangular area to be extracted and the reflection in the flag table 16 to be completed. When the completion of the update rectangular area extraction process is detected, the process proceeds to step S106. In step S106, the flag information in the flag table 16 is read, and the read flags are cleared. Next, the screen area to be transmitted is determined from the flag information extracted in step S107. Next, in step S108, the display screen data of the area to be transmitted is extracted from the display buffer 7, and in step S109, the extracted display screen data of the area to be transmitted is compressed by the image compression device 11 and sent to the communication device 9. send. Next, the compressed display screen data received by the communication device 9 in step S110 is transmitted to the display terminal device. Then, the process returns to step S105, waits for the update rectangular area between the next frames to be extracted, and repeats this process until a disconnection request is received from the display terminal device 2.

【0037】

Therefore, according to this embodiment, it is possible to extract the update screen area between frames without imposing a burden on the CPU of the information processing device.

【0038】

(Embodiment 2) Embodiment 2 of the present invention will be described with reference to the drawings. FIG. 4 is a block diagram showing the overall configuration of the second embodiment of the remote display screen update system of the information processing device, and transmits the display screen to the display terminal device 2 that displays the display screen remotely and the remote display terminal device 2. It is composed of a communication line 3 connecting the information processing device 1 and the information processing device 1 and the display terminal device.

【0039】

Here, the information processing device 1 sets the frame data of the CPU 4, the main memory 5, the large-capacity storage device 6, the communication device 9, the video controller 8, the display buffer 7, the input device 10, the image compression device 11, and the display screen in frame units. It is composed of a memory A12 and a memory B13 which are storage means for storing actual display frames, a memory switching control circuit 14, an update rectangular area extraction circuit 15, and a flag table 16.

【0040】

In the second embodiment, the memory switching control circuit 14 alternately switches between the memory A12 and the memory A13 in frame units according to the frame control signal (for example, the vertical synchronization signal) of the video controller 8 to pixel clock the frame data of the display screen. The rectangular area extraction circuit 15 updates at the same time while storing at the rate. The frame data of the display screen output from the video controller 8 is compared with the previous frame data stored in either the memory A12 or the memory B13 in real time. When the difference in the pixel data in the predetermined rectangular area is detected, it is reflected in the corresponding flag in the flag table 16.

【0041】

The operation of the remote display screen update system of the information processing device of the second embodiment is the same as the processing flow described in the first embodiment, and the operation of the remote display screen update system of the information processing device of the first embodiment. This will be described with reference to the flowchart of FIG. 3 showing.

【0042】

First, when a display screen request is received from the connected display terminal device 2, in step S101, the video controller 8 starts storing the frame data of the display screen in units of one frame in the memory. Next, S102 extracts all the data of the display screen recorded in the display buffer. Next, in step S103, the extracted display screen data is compressed by the image compression device 11 and sent to the communication device 9. In step S104, the compressed display screen data received by the communication device is transmitted to the display terminal device. Next, in step S105, the updated rectangular area extraction circuit 15 compares the previous frame data captured in one of the memory A12 and the memory B13 with the frame data output from the current video controller 8, and the updated rectangular area is extracted. When it waits for the reflection in the flag table to be completed and detects the completion of the update rectangular area extraction process, the process proceeds to step S106. In step S106, the flag information in the flag table 16 is read, and the read flags are cleared. Next, the screen area to be transmitted is determined from the flag information extracted in step S107. Next, in step S108, the display screen data of the area to be transmitted is extracted from the display buffer 7, and in step S109, the extracted display screen data of the area to be transmitted is compressed by the image compression device 11 and sent to the communication device 9. send. Next, the compressed display screen data received by the communication device in step S110 is transmitted to the display terminal device 2. Then, the process returns to step 105, waits for the completion of the update rectangular area extraction process between the next frames, and repeats this process until a disconnection request is received from the display terminal device.

【0043】

As described above, it is possible to extract the update screen area between frames in real time without imposing a burden on the CPU of the information processing device, and it is possible to quickly respond to the update of the display screen.

【0044】

(Embodiment 3) Embodiment 3 of the present invention will be described with reference to the drawings. FIG. 5 is a block diagram showing the overall configuration of the third embodiment of the remote display screen update system of the information processing device. It is composed of a communication line 3 connecting an information processing device 1 for transmitting information, an information processing device 1 and a display terminal device 2.

【0045】

Here, the information processing device 1 sets the frame data of the CPU 4, the main memory 5, the large-capacity storage device 6, the communication device 9, the video controller 8, the display buffer 7, the input device 10, the image compression device 11, and the display screen in frame units. It is composed of a memory A12 and a memory B13 which are storage means for storing actual display frames, a memory switching control circuit 14, an update rectangular area extraction circuit 15, and a flag table 16.

【0046】

In the third embodiment, the frame control signal of the video controller 8 (the memory switching control circuit 14 alternately switches the memory A12 and the memory A13 in frame units according to the vertical synchronization signal, and stores the frame data of the display screen at the pixel clock rate. At the same time, the updated rectangular area extraction circuit 15 compares the frame data of the display screen output from the video controller with the previous frame data stored in either the memory A12 or the memory A13 in real time, and determines a predetermined rectangular area. When the difference in the pixel data in the memory is detected, it is reflected in the corresponding flag in the flag table 16. The memory A12 and the memory B13 can be read directly from the CPU 4 via the system bus I / F17.

【0047】

Next, the operation of the remote display screen update system of the information processing apparatus according to the third embodiment will be described. FIG. 6 is a flowchart showing the processing of the remote display screen update system of the information processing apparatus according to the third embodiment.

【0048】

First, when the display screen request is received from the connected display terminal device 2, in step S201, the video controller starts storing the frame data of the display screen for one frame in the memory A12. Next, in step S202, it waits for the storage of the frame data of the display screen for one frame to be completed. When the storage of the frame data of the display screen for one frame is completed, the frame data of the stored display screen is extracted from the memory A12 in step S203. In step S204, the extracted display screen data is compressed by the image compression device 11 and sent to the communication device 9. In step S205, the compressed display screen data received by the communication device is transmitted to the display terminal device. Next, in step S206, the updated rectangular area extraction circuit 15 compares the frame data of the display screen captured in the memory A12 with the frame data of the next display screen output from the video controller, and the updated rectangular area is extracted and the flag is extracted. When the completion of the update rectangular area extraction process is detected after waiting for the reflection to the table to be completed, the process proceeds to step S207. In step S207, the flag information in the flag table is read, and the read flags are cleared. Next, the screen area to be transmitted is determined from the flag information extracted in step S208. Next, in step S209, the display screen data of the area to be transmitted is extracted from the memory B13 in which the frame data of the display screen of this time is stored, and in step S210, the displayed display screen data of the extracted area to be transmitted is image-compressed. It is compressed by the device 11 and sent to the communication device 9. Next, the compressed display screen data received by the communication device in step S211 is transmitted to the display terminal device. Then, the process returns to step S206, waits for the update rectangular area of the next frame to be extracted, and repeats this.

【0049】

As a result, it is possible to extract the update screen area between frames in real time without imposing a burden on the CPU of the information processing device, it is possible to quickly respond to the update of the display screen, and the actual output from the video controller. Since the display screen data of the above can be transmitted to the display terminal device, it was drawn by a drawing command (for example, screen drawing by Direct Draw of WINDOWS) that does not write the pixel data directly to the display buffer using the acceleration function of the video controller. The display screen can also be updated.

【0050】

In the third embodiment, an example of using two memories as the actual display frame storage means has been described. However, one memory or two or more memories may be used, but it is realized by one memory. Requires faster memory with less bandwidth limitation than it would be with more than one memory.

【0051】

(Embodiment 4) Next, Embodiment 4 of the present invention will be described. FIG. 7 shows a block diagram of the overall configuration of the fourth embodiment of the remote display screen update system of the information processing device. In the fourth embodiment, in addition to the configuration of the third embodiment, the frame data of the display screen output from the video controller 8 is stored in the actual display screen frame storage means in frame units at intervals of a plurality of frames. It is configured to have a frame storage rate control circuit 31 that performs rate control. The frame storage rate control circuit 31 includes a counter that counts the number of frames from the frame control signal of the video controller, and a frame rate setting register that sets the frame rate to be stored in the memory.

【0052】

The frame storage rate control circuit counts the number of frames from the frame control signal (for example, vertical synchronization signal, etc.) of the video controller, and when the counted number matches the number set in the frame rate setting register, the memory switching control circuit 14 Is switched between memory A12 and memory B13, and at the same time, the storage of the display screen data of the video controller is started in one memory, and at the same time, the other memory is connected to the update rectangular area extraction circuit 15 to start the update area extraction process. Then, the number of frames is counted from the frame control signal (vertical synchronization signal, etc.) of the video controller, and while the counted number does not match the number set in the frame rate setting register, the display screen data of the video controller 8 is stored in the memory. The storage process and the update rectangular area extraction process are not operated.

【0053】

As described above, when it is not necessary to quickly respond to the update of the display screen, the user can reduce the process of extracting an unnecessary update area by setting the update detection frame rate, which consumes the information processing device 1. The power consumption can be reduced, and the display screen data of the unnecessary update area does not have to be transmitted to the display terminal, so that the transmission band can be saved.

【0054】

(Embodiment 5) Next, Embodiment 5 of the present invention will be described. The overall configuration of the fifth embodiment of the remote display screen update system of the information processing device is the same as that of the fourth embodiment. In the fifth embodiment, the information processing device 1 is configured to have a display screen update determination means for determining whether or not the display screen has been updated within a predetermined period or a predetermined frame storage count period. To.

【0055】

Next, the operation of the display screen update determination means will be described with reference to the flowchart of FIG. First, in step S301, a timer that counts a predetermined time or a predetermined number of frame storages is operated. When the timer starts operation, it issues a count end notification every time it counts a predetermined time or a predetermined number of frames. Next, in step S302, the display screen update count processing for counting the number of times the display screen is updated is started. Next, in step S303, the timer count end notification is waited for. When the timer count end notification is detected, the count value of the display screen update count processing is read in step S304, and the count value is cleared. Next, in step S305, a predetermined value is written in the frame storage rate setting register according to the read display screen update count, the frame storage rate is changed, the process returns to step S303, and the count ends in the next period is waited for.

【0056】

Here, the operation of the display screen update count processing will be described. FIG. 9 is a flowchart of the display screen update count processing. In step S401, the update screen area extraction circuit 15 waits for the update screen area extraction process to be completed. When the end of the update screen area extraction process is detected, in step S402, check whether the flag to notify the update is set in the flag table, and if it is set, add 1 to the number of display screen updates in step S403, and step. Return to S401, wait for the update screen extraction process of the next frame to finish, and if the flag is not set, do nothing, return to step S401, and wait for the update screen extraction process of the next frame to finish. wait.

【0057】

As described above, when the display screen is hardly updated, the update detection frame rate can be lowered, the process of extracting an unnecessary update area can be reduced, and the power consumption of the information processing device 1 can be reduced.

【0058】

(Embodiment 6) Next, Embodiment 6 of the present invention will be described. The overall configuration of the sixth embodiment of the remote display screen update system of the information processing device is the same as that of the fourth embodiment. In the sixth embodiment, the communication device 9 of the information processing device 1 has a transmission buffer of a predetermined size, and the information processing device 1 has a means for detecting the remaining amount of the transmission buffer at predetermined time intervals and transmits. If the remaining amount of the buffer is less than the predetermined value, the frame storage rate of the frame storage rate control circuit 31 is lowered, and if the remaining amount is more than the predetermined value, the frame storage rate of the frame storage rate control circuit is increased. Configure.

【0059】

Next, the operation of this frame storage rate control will be described with reference to the flowchart of FIG. First, in step S501, a timer that counts a predetermined time or a predetermined number of frame storages is operated. When the timer starts operation, it issues a count end notification every time it counts a predetermined time or a predetermined number of frames. Next, in step S502, the timer count end notification is waited for. When the timer count end notification is detected, in step S503, the remaining amount of the transmission buffer of the communication device 9 is confirmed. Next, in step S504, if the remaining amount of the transmission buffer of the communication device 9 is equal to or more than the predetermined value, the frame storage rate of the frame storage rate control circuit 31 is increased, and if it is equal to or less than the predetermined value, the frame storage rate is decreased. Change the frame storage rate setting to, return to step S502, and repeat this process.

【0060】

As described above, by checking the remaining amount of the buffer of the communication device, it is possible to reduce the process of extracting a useless update area exceeding the communication capacity, reduce the power consumption of the information processing device, and further, the unnecessary update area. It is not necessary to transmit the display screen data to the display terminal, and the transmission band can be saved.

【0061】

(Embodiment 7) Next, Embodiment 7 of the present invention will be described. The overall configuration of the seventh embodiment of the remote display screen update system of the information processing device is the same as that of the third embodiment. The configuration of the updated rectangular region extraction circuit 15 of the seventh embodiment will be described below.

【0062】

As shown in FIG. 11, the updated rectangular area extraction circuit 15 is an arithmetic unit that calculates the absolute value of the difference between each RGB component for each pixel of the frame data from the video controller 8 and the frame data stored in the previous memory. If the difference between the pixels in the predetermined rectangular area is greater than or equal to the predetermined value even for one pixel from the result of the calculation, it is determined that there is a difference to be transmitted to the predetermined rectangular area, and the pixels in the predetermined rectangular area are predetermined. If it is less than or equal to the value of and is not zero, it is not a difference to be transmitted, but it is composed of an update determination circuit 42 that determines that there is a difference.

【0063】

Next, the operation will be described. When the update rectangular area extraction process is started, the arithmetic unit 41 calculates the absolute value of the difference of each pixel component for each pixel of the frame data from the video controller 8 and the frame data stored in the previous memory. Next, in the update determination circuit, if the absolute value of the difference for each pixel is a predetermined value (for example, 4) or more as a result of the calculation, it is assumed that there is a difference to be transmitted to the predetermined rectangular area, and the flag table 16 shows. Reflected in the flag corresponding to the rectangular area including the pixel, if the absolute value of the difference for each pixel is smaller than a predetermined value (for example, 4), it is judged that it is not a difference to be transmitted, and the flag table It works so that it is not reflected in 16.

【0064】

From the above, when the change in the color component of each pixel in the predetermined rectangular area is slight between the frames before and after, it is determined that the rectangular area is not the area to be transmitted, and the rectangular area is not transmitted to the display terminal device. , The screen of the display terminal device in the area where there is only a slight color change that cannot be seen by the human eye is not updated, and the transmission band can be saved.

【0065】

(Embodiment 8) Next, Embodiment 8 of the present invention will be described. This is the same as the overall configuration of the third embodiment of the remote display screen update system of the information processing device. The configuration of the updated rectangular region extraction circuit 15 of the eighth embodiment will be described below.

【0066】

As shown in FIG. 12, the updated rectangular area extraction circuit 15 was detected by a comparator 51 that compares the frame data from the video controller 8 with the frame data previously stored in the memory pixel by pixel, and a comparator 51. If the number of differences between the pixels in the predetermined rectangular area counted by the difference pixel counting circuit 52 and the difference pixel counting circuit 52 counting the number of differences in the pixels in the predetermined rectangular area is equal to or more than a predetermined value, the difference is within the rectangular area. It is composed of an update determination circuit 53 that determines that there is an area to be transmitted and determines that there is no area to be transmitted when the number of differences in pixels in a predetermined rectangular area is less than a predetermined value.

【0067】

Next, the operation will be described. When the update rectangular area extraction process is started, the comparator 51 sets the frame data from the video controller 8 and the frame data stored in the previous memory one pixel at a time, and sets a predetermined rectangular area (corresponding to one flag in the flag table). For example, the comparison is made in units of (area composed of 8 × 8 pixels). Next, the difference pixel counting circuit 52 counts the number of pixels detected as having a difference in one rectangular region. In the update determination circuit 53, the comparison of all the pixels in one rectangular area is completed, and the number of different pixels in one rectangular area counted by the different pixel counting circuit 52 is a predetermined value (for example, one rectangular area is 8). In the case of an area of × 8 pixels, if it is 16) or more, it is assumed that there is a difference to be transmitted to a predetermined rectangular area, and it is reflected in the flag corresponding to the rectangular area including that pixel in the flag table, and the difference pixel count is counted. If the number of different pixels in one rectangular area counted by the circuit 52 is less than a predetermined value (for example, 16 if one rectangular area is an area of 8 × 8 pixels), there is no difference to be transmitted. It is judged that it is not reflected in the flag table.

【0068】

From the above, when the number of changes in the pixels in the predetermined rectangular area is small between the frames before and after, it is determined that the rectangular area is not the area to be transmitted and is not transmitted to the display terminal device. It is only necessary to transmit the update screen data only in the area where there is a large change, and the transmission band can be saved.

【0069】

(Embodiment 9) Next, Embodiment 9 of the present invention will be described. This is the same as the overall configuration of the third embodiment of the remote display screen update system of the information processing device. The configuration of the updated rectangular region extraction circuit 15 of the ninth embodiment will be described below.

【0070】

As shown in FIG. 13, the updated rectangular area extraction circuit 15 is a DCT (discrete cosine transform) operation that converts the frame data from the video controller and the frame data stored in the previous memory into frequency components in predetermined rectangular area units. Instrument 61, comparer 62 that compares the frequency component data of a predetermined rectangular area obtained by the DCT calculator, and if there is a difference in frequency components lower than the predetermined frequency, there is an area to be transmitted in the rectangular area. It is composed of an update determination circuit 63 that determines that there is no region to be transmitted if there is no difference in frequency components lower than a predetermined frequency.

【0071】

Next, the operation will be described. When the update rectangular area extraction process is started, the update rectangular area extraction circuit 15 sets the frame data from the video controller and the frame data stored in the previous memory into a predetermined rectangular area corresponding to one flag in the flag table (respectively). For example, the DCT calculator 61 converts the pixel data into the frequency component data in units of (area composed of 8 × 8 pixels). Next, the comparator 62 compares each frequency component. The update determination circuit 63 refers to the result of the comparator, and if there is a difference in frequency component within a predetermined low frequency component region, the pixel of the flag table is included as a difference to be transmitted to a predetermined rectangular region. If there is no difference in the frequency component within the predetermined low frequency component region, it is transmitted to the predetermined rectangular region even if there is a difference in the frequency region outside the predetermined low frequency component region. Judge that there is no difference that should be done, and operate so that it is not reflected in the flag table. In the ninth embodiment, DCT transform is used as a means for converting pixel data into frequency components, but the present invention is not limited to this, and other orthogonal transforms (for example, Hadamard transform and Carunenlebe transform) are used. You may.

【0072】

From the above, when the DC and low frequency components of the pixel data in the predetermined rectangular area do not change between the preceding and following frames, it is determined that the rectangular area is not the area to be transmitted, and the display terminal device is used. Since it is not transmitted, the update screen data in the area where only the high frequency component that cannot be recognized by the human eye has changed is not transmitted, and the transmission band can be saved.

【0073】

(Embodiment 10) Next, Embodiment 10 of the present invention will be described. FIG. 14 is a block diagram showing the overall configuration of the tenth embodiment. In the tenth embodiment, the information processing device 1 includes a CPU 4, a main memory 5, a large-capacity storage device 6, a communication device 9, a video controller 8, a display buffer 7, an input device 10, an image compression device 11, and frame data of a display screen. It is composed of memory A12 and memory B13 which are actual display frame storage means for storing the data in frame units, a memory switching control circuit 14, an update rectangular area extraction circuit 15, a transmission notification flag table 71, and an update notification flag table 72.

【0074】

Here, the updated rectangular area extraction circuit 15 calculates the frame data from the video controller and the frame data stored in the memory in the previous time in units of a predetermined rectangular area, and then uses the calculation result as a predetermined criterion. Judgment is made to determine whether there is a difference to be transmitted in the rectangular area, and if it is determined that there is a difference to be transmitted, the corresponding flag in the transmission notification flag table 71 is set, and although there is a difference, transmission should be performed. If it is determined that there is no difference, the corresponding flag in the update notification flag table 72 is set. Further, the flag of the update notification flag table is cleared when the flag corresponding to the same rectangular area of the transmission notification flag table is set. For the determination of whether or not it is a rectangular area to be transmitted, the absolute value of the difference in the color components of each pixel in the rectangular area described in the seventh to ninth embodiments is used, or the pixels having a difference in the rectangular area are used. It is possible to make a judgment by using the number of the above, or by converting the pixel data in the rectangular region into a frequency component and using which frequency component is different.

【0075】

Next, the operation of the tenth embodiment will be described. FIG. 15 is a flowchart showing the processing of the remote display screen update system of the information processing apparatus according to the tenth embodiment.

【0076】

First, when a display screen request is received from the connected display terminal device 2, the operation of the timer that measures a predetermined time is started in step S601. When the timer starts operation, it issues a count end notification every time it counts a predetermined time. Next, in step S602, the video controller 8 starts storing the frame data for one frame in either the memory A12 or the memory B13. Next, in step S603, the completion of storing the frame data for one frame is waited for. When the storage of the frame data of the display screen for one frame is completed, the frame data of the display screen stored in either the memory A12 or the memory B13 is extracted in step S604. In step S605, the extracted display screen data is compressed by the image compression device 11 and sent to the communication device 9. In step S606, the compressed display screen data received by the communication device is transmitted to the display terminal device.

【0077】

Next, in step S607, the update rectangular area extraction circuit 15 waits for the transmission rectangular area extraction process to be completed from the frame data stored in the memory and the next frame data output from the video controller, and then extracts the transmission rectangular area. When the completion of the process is detected, the process proceeds to step S608. In step S608, it is confirmed whether or not the timer count end notification has been received, and if the count end notification has not been received, the predetermined time has not been reached, so the process proceeds to step S609, and in step S609, the transmission notification flag table Read the flag information of 71 and clear the read flag. Next, the screen area to be transmitted is determined from the flag information extracted in step S610. Next, in step S611, the display screen data of the area to be transmitted is extracted from the memory A12 or the memory B13 in which the frame data of the display screen of this time is stored, and in step S612, the displayed display screen data of the extracted area to be transmitted is extracted. Is compressed by the image compression device 11 and sent to the communication device 9. Next, the compressed display screen data received by the communication device 9 in step S613 is transmitted to the display terminal device 2. Then, the process returns to step S607, waits for the transmission rectangular area of the next frame to be extracted, and repeats this. Then, when the predetermined time elapses and the count end notification is received in step S608, the process proceeds to step S614, and in step S614, the flag information in the transmission notification flag table 71 is read, the read flags are cleared, and the next step S615 is performed. Reads the flag information in the update notification flag table 72 with, and clears the read flags. Next, in step S616, the screen area corresponding to the flag information extracted from the transmission notification flag table 71 and the screen area corresponding to the flag information extracted from the update notification flag table 72 are determined as the screen areas to be transmitted, and then the screen area is determined. In step S611, the display screen data of the area to be transmitted is extracted from the memory in which the frame data of the display screen of this time is stored, and in step S612, the display screen data of the extracted area to be transmitted is displayed. It is compressed by the image compression device 11 and sent to the communication device 9. Next, the compressed display screen data received by the communication device 9 in step S613 is transmitted to the display terminal device. Then, the process returns to step S607, waits for the transmission rectangular area of the next frame to be extracted, and repeats the same process thereafter.

【0078】

Based on the above, according to the tenth embodiment, when there is a slight change in the predetermined rectangular area between the preceding and following frames, it is determined that the rectangular area is not an area to be transmitted, and the rectangular area is not transmitted to the display terminal device. Therefore, it is possible to save the transmission band, and further, the change of the predetermined rectangular area between the frames before and after is small, and the rectangular area determined that the rectangular area is not the area to be transmitted is also set at regular intervals. Since it is transmitted, it is not necessary to update the full screen on a regular basis even when an accurate display screen is required.

【0079】

(Embodiment 11) Next, Embodiment 11 of the present invention will be described. The overall configuration of the eleventh embodiment is the same as that of the tenth embodiment, but as shown in FIG. 16, the update notification flag table 72 shows the rectangular area to be transmitted by the update rectangular area extraction circuit 15 although there are differences. When it is determined that the flag is not set, it has an area 81 for setting a flag and a flag set number storage area 82 for storing the number of times the flag is set for each flag, and the update rectangular area extraction circuit has an update notification flag table 72. Each time each flag is set, the value of the flag set count storage area 82 is incremented, and when the value reaches a predetermined value, the value and flag of the flag set count storage area 82 are cleared, and the transmission notification flag table is used. Set the flag corresponding to the same rectangular area of 71. Further, similarly to the flag of the update notification flag table 72 of the eleventh embodiment, when the flag corresponding to the same rectangular area of the flag transmission notification flag table 71 is set, the flag of the update notification flag table 72 is cleared.

【0080】

In the case of such a configuration, if there is a slight change in the predetermined rectangular area between the preceding and following frames, it is determined that the area is not to be transmitted, and the rectangular area that has not been transmitted to the display terminal device also has a slight change. When is detected a certain number of times, it is reflected in the transmission notification flag table, and it is possible to transmit to the display terminal device as an area to be transmitted, and it is possible to deal with the case where the display screen changes very slowly. It becomes.

【0081】

(Embodiment 12) Next, Embodiment 12 of the present invention will be described. The configuration of the twelfth embodiment is the same as the overall configuration of the third embodiment. In this method, the information processing apparatus 1 further divides the display screen into several screen areas, and each of the divided areas is divided. It has an area priority setting means for setting a priority, and updates the screen area corresponding to the area at predetermined time intervals according to the set priority.

【0082】

This will be described with reference to the figures. For example, FIG. 17 is an example of a display screen. On this screen, several windows overlap. In FIG. 17, window X101 is the top-level window and is currently active.

【0083】

Here, the area priority setting means sets the priority for each of the areas corresponding to the window X101 as the area A102 and the other areas as the area B103. For example, the priority of the area A102 is 1, and the priority of the area B103 is 4. There are various levels of priority, and the time to update the screen is preset for each priority. For example, priority 1 is every 1/10 second, and priority 4 is every 4 seconds. And so on. Then, the information processing device reads the flag of the flag table corresponding to the area A102 every 1/10 second, extracts only the updated rectangular area of the area A102, transmits it to the display terminal device 2, and transmits it to the display terminal device 2 every 4 seconds. The flag of the flag table corresponding to the area B103 is read, and the updated rectangular area of the area B103 is extracted and transmitted to the display terminal device 2.

【0084】

In this example, the area was divided into two, but the area may be divided into any number, and the update time was set to update each area according to the flag priority level. For example, in the case of priority 1, it may be set in units of 1 frame, in the case of priority 4, it may be set in units of 40 frames, and so on.

【0085】

As described above, the display screen can be divided into a plurality of screen areas, and the rate at which the screen is updated can be changed for each divided area. Therefore, by lowering the update rate of the unimportant area, the amount of data to be transmitted can be reduced. Become.

【0086】

(Embodiment 13) Next, the thirteenth embodiment of the present invention will be described. The configuration of the thirteenth embodiment is the same as the overall configuration of the third embodiment. In this method, the information processing apparatus 1 further updates the flag by counting the number of times each flag of the flag table is set within a predetermined time. Area priority setting means that has a number of times detecting means, divides the display screen into several screen areas according to the number of times each counted flag is set, and sets a priority for each divided area. The screen area corresponding to the area is updated at predetermined time intervals according to the set priority.

【0087】

Next, this will be described with reference to the drawings. FIG. 18 is an example in which the number of times the flag is set in a predetermined time (for example, 10 seconds) is counted by the flag update number counting means. This flag update count detecting means provides, for example, an area for recording the flag update count in the main memory, and each time the flag is read from the flag table, if there is a set flag, the flag update corresponding to the flag is provided. This can be achieved by incrementing the number of updates recorded in the area for recording the number of times. Here, the area priority setting means first divides the display screen into a plurality of screen areas according to the number of times each flag is updated. For example, in FIG. 18, the area X111 is a group in which the number of flag updates is 0 to 2, the area Y112 is a group of 3 to 10 times, and the area Z113 is a group of 10 or more times. Then, the priority of the area Z113 having the most flag updates is set to 1, the priority of the area Y112 having the next most flag updates is 2, and the priority of the area X111 having the least number of flag updates is set to 5. ..

【0088】

Here, there are various levels of priority, and the time for updating the screen is preset for each priority. For example, in the case of priority 1, every 1/10 second, in the case of priority 2, Every second, in the case of priority 5, every 5 seconds, and so on.

【0089】

Then, the information processing device reads the flag of the flag table corresponding to the area Z113 every 1/10 second, extracts only the updated rectangular area of the area Z113, transmits it to the display terminal device 2, and transmits it to the display terminal device 2 every 1 second. The flag of the flag table corresponding to the area Y112 is read, the updated rectangular area of the area Y112 is extracted and transmitted to the display terminal device 2, the flag of the flag table corresponding to the area X111 is read every 5 seconds, and the area is read. The updated rectangular area of X111 is extracted and transmitted to the display terminal device 2.

【0090】

As described above, depending on the frequency of flag update, the screen area can be divided into a plurality of areas, the screen update rate for each area can be changed, and the area with high activity of change of the display screen can be preferentially updated. Will be.

【0091】

(Embodiment 14) Next, Embodiment 14 of the present invention will be described. The configuration of the 14th embodiment is the same as the overall configuration of the 3rd embodiment. In this method, the information processing apparatus 1 further detects the currently operating application program, and the individual application programs are displayed on the display screen. It has an application display position detecting means for detecting which area of the application is displayed, and an application program drawing screen characteristic table in which each application program and the characteristics of the screen drawn by the application program are associated with each other. Each application program drawing area detected by the detection means has an area priority setting means for setting the priority using the application program drawing screen characteristic table, and the screen area corresponding to the area is determined according to the set priority. Make sure to update every hour.

【0092】

Next, this will be described with reference to the drawings. The application display position detecting means, for example, operates a program that monitors commands for the operating system on the operating system of the information processing device 1, and detects drawing commands issued by each application program for the operating system. By doing so, it is possible to know in which area of the display screen the application program is currently displaying. In addition, an application program drawing screen characteristic table 121 associated with screen characteristics (for example, moving images, still images, character strings, etc.) drawn by an application program that can be executed by the information processing device is prepared in advance. FIG. 19 shows an example of the application program drawing screen characteristic table.

【0093】

For example, in FIG. 20, the application program 1 draws in the display screen area α131, and the application program 2 draws in the display screen area β132. Here, the application program display position detecting means can detect that the application program 1 is drawing in the area α131 and the application program 2 is drawing in the area β132. Next, from the application program drawing screen characteristic table 121 shown in FIG. 19, the area α131 is the area where the moving image is drawn, the area β132 is the area where the character string is drawn, and the other area γ133 is the application program. Is not drawn, and the area priority setting means is, for example, the area α131 has a priority of 1 because a moving image is drawn, and the area β132 has a priority because a character string is drawn. 3 and the area γ133 are not drawn by the application program, so the priority can be set to 10.

【0094】

Here, there are various levels of priority, and the time for updating the screen is preset for each priority. For example, in the case of priority 1, every 1/30 second, in the case of priority 3, the time is set. Every 3 seconds, if the priority is 10, every 10 seconds, and so on.

【0095】

Then, the information processing device reads the flag of the flag table corresponding to the area α131 every 1/30 second, extracts only the updated rectangular area of the area α131 and transmits it to the display terminal device, and every 3 seconds. The flag of the flag table corresponding to the area β132 is read, the updated rectangular area of the area β132 is extracted and transmitted to the display screen, the flag of the flag table corresponding to the area γ133 is read every 10 seconds, and the area γ133 is updated. The squared area is extracted and transmitted to the display screen.

【0096】

From the above, it is possible to update the screen suitable for the screen characteristics of the display screen by detecting the application program drawing on the display screen and referring to the screen characteristics drawn by the application program registered in advance. It becomes.

【0097】

(Embodiment 15) Next, Embodiment 15 of the present invention will be described. The configuration of the fifteenth embodiment is the same as the overall configuration of the third embodiment, but as shown in FIG. 21, the image compression device 11 has at least one lossless compression means 141 and at least one lossy compression means 142. To do so. The lossless compression means 141 includes, for example, Huffman coding, arithmetic coding, and the like, and the lossy compression means 142 includes, for example, JPEG using DCT (discrete cosine transform).

【0098】

In this method, the information processing device 1 has an area-specific compression method selection means for dividing the display screen into several screen areas and setting a compression method for each divided area, and corresponds to the divided areas. Each screen area to be processed is compressed by the compression method selected by the area-specific compression method selection means and transmitted to the display terminal device.

【0099】

Next, the operation will be described. FIG. 22 is an example of the display screen of the information processing device 1 according to the fifteenth embodiment. On this screen, several windows overlap. In FIG. 22, window W151 is the top-level window and is currently active.

【0100】

The area-specific compression method selection means, for example, asks the operating system which window is currently active, recognizes that the window W151 is active, sets the area corresponding to the window W151 to the area A152, and other areas. Set the area as area B153 and set the compression method for each area. For example, since region A152 is an active window and an image without blurring or distortion is required, Huffman coding, which is a lossless compression means 141, is set, and region B153 is an inactive region, so that the accuracy of the image is increased. Since sharpness is not required, JPEG, which is a lossy compression means 142, is set. Then, the information processing device 1 reads the flag of the flag table 16 corresponding to the area A152, extracts the rectangular area updated in the area A152, and Huffman-encodes the screen data of the rectangular area to be transmitted by the lossless compression means 141. It is transmitted to the display terminal device 2, then the flag of the flag table 16 corresponding to the area B153 is read, the rectangular area updated in the area B153 is extracted, and is transmitted to the display terminal device 2.

【0101】

In the present embodiment, the area-specific compression method selection means detects an active window as a method of dividing the display screen area into a plurality of areas and setting a compression method for each area, and the active window thereof. The display screen area is divided into a plurality of areas depending on whether the area is the same or not, and the compression method is set. However, for example, as described in the thirteenth embodiment, the area is divided by the number of times the flag is updated for a predetermined time. The compression method of each area may be set by dividing into a plurality of areas, or as described in the 14th embodiment, the area is divided according to the screen area drawn by the application program, and the compression method of each area is set. It may be set.

【0102】

As described above, the display screen can be divided into a plurality of screen areas, and the compression method can be changed for each divided area. Therefore, lossy compression can be used for an unimportant area or a moving image area, and the amount of data to be transmitted can be reduced. Is possible.

【0103】

[Effect of the invention]

According to the present invention, in the remote display screen update system of the information processing device that transmits the display screen of the information processing device to the remote display screen and displays it, the load on the CPU of the information processing device that transmits the display screen is reduced, and the remote display screen is transmitted. The display screen of the display terminal device can be updated quickly, the display screen can be updated by any drawing command, the amount of data transmitted can be reduced without the user feeling visually uncomfortable, and the remote display terminal can be used. The device has an effect that the display screen of the information processing device can be quickly updated even when the drawing processing capacity of the device is inferior to that of the information processing device, such as a portable terminal device that requires low power consumption.

[Simple explanation of drawings]

FIG. 1 is a block diagram showing the overall configuration of the first embodiment of the remote display screen update system of the information processing device. [Fig. 2] A diagram showing the relationship between a flag and a display screen. [Fig. 3] Information processing of the first embodiment. Flow chart showing the processing of the remote display screen update system of the device [Fig. 4] Block diagram showing the overall configuration of the second embodiment of the remote display screen update system of the information processing device [Fig. 5] Remote display screen update of the information processing device Block diagram showing the overall configuration of the third embodiment of the system [Fig. 6] Flow chart showing the processing of the remote display screen update system of the information processing device of the third embodiment [Fig. 7] Remote display screen update system of the information processing device FIG. 8 is a block diagram showing the overall configuration of the fourth embodiment of the above. FIG. 8 is a flowchart showing the processing of the display screen update determination means of the fifth embodiment. [FIG. 9] The display screen update count processing of the fifth embodiment is shown. Flowchart [Fig. 10] Flowchart showing the frame storage rate control process of the sixth embodiment [Fig. 11] Block diagram showing the configuration of the updated rectangular area extraction circuit of the seventh embodiment [Fig. 12] Update of the eighth embodiment. Block diagram showing the configuration of the rectangular area extraction circuit [Fig. 13] Update of the ninth embodiment Block diagram showing the configuration of the rectangular area extraction circuit [Fig. 14] Overall of the tenth embodiment of the remote display screen update system of the information processing apparatus Block diagram showing the configuration [Fig. 15] Flow chart showing the processing of the remote display screen update system of the information processing apparatus of the tenth embodiment [Fig. 16] Fig. 17 showing the configuration of the update notification flag table of the eleventh embodiment. FIG. 18 is a diagram showing an example of a display screen of the information processing apparatus according to the twelfth embodiment. FIG. FIG. 19 is a diagram showing an example of a result. FIG. 19 is a diagram showing an example of an application program drawing screen characteristic table of the 14th embodiment. FIG. 20 is a diagram showing an example of a display screen of the information processing apparatus of the 14th embodiment. Block diagram of the image compression device according to the fifteenth embodiment [FIG. 22] A diagram showing an example of a display screen of the information processing apparatus according to the fifteenth embodiment [FIG. 23] Remote display screen modification of the conventional information processing apparatus.Block diagram showing the configuration of the new system [Explanation of symbols]

1 Information processing device 2 Display terminal device 3 Communication line 4 CPU5 Main memory 6 Large-capacity storage device 7 Display buffer 8 Video controller 9 Communication device 10 Input device 11 Image compression device 12 Memory A13 Memory B14 Memory switching control circuit 15 Update rectangular area extraction circuit 16 Flag table 17 System bus I / F (interface) 21 8 × 8 pixel rectangular area 22 Flag corresponding to rectangular area 31 Frame storage rate control circuit 41 Arithmetic unit that calculates the absolute value of the difference for each RGB component 42 Pixel component Update judgment circuit that judges whether there is a difference to be transmitted to a predetermined rectangular area from the absolute value of the difference of Pixel counting circuit 53 Update judgment circuit that determines whether there is a difference to be transmitted to a predetermined rectangular area based on the number of differences in pixels in a predetermined rectangular area 61 DCT (discrete cosine conversion) that converts pixels in a predetermined rectangular area into frequency components ) Arithmetic 62 Comparer that compares the frequency components of a given rectangular area 63 Update judge 71 that determines whether there is a difference that should be transmitted in the specified rectangular area based on whether there is a difference in frequency components lower than the specified frequency 71 Transmission notification flag table 72 Update notification flag table 81 Update notification flag table flags Area to be set 82 Update notification flag table flag set count Storage area 101 Window X102 Area corresponding to window X A103 Area other than window X Display screen area B111 Area where the number of updates is 0 to 2 X112 The number of updates is Area 3 to 10 times Y113 Area where the number of updates is 10 or more Z121 Application program drawing screen characteristic table 131 Area where application program 1 is drawing α132 Area where application program 2 is drawing β133 Area α, area other than area β Display screen area γ141 Lossy compression means 142 Lossy compression means 151 Window W152 Area corresponding to window W A153 Area other than window W display screen area B303 Communication line 304 CPU305 Main Memory 306 Mass storage 307 Display buffer 308 Video controller 309 Communication device 310 Input device S101 to S616 Flowchart steps