JP2015208021A - Moving image communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a system, a method and a program, with which image quality of a whole interest region does not suddenly drop when a transmission amount of a moving image is suppressed.SOLUTION: Transfer image generation means 140 of a transmitter 100 generates image data from a frame image of a moving image so that image quality of an interest region becomes higher than other regions, and transmits it to a reception device 200 by communication means 110. Communication rate measuring means 120 measures a communication rate of the communication means 110. Interest region information managing means 130 reduces a size of the interest region when the measured communication rate reaches a first threshold. Screen display means 220 of the reception device 200 displays the moving image based on the image data received by communication means 210 on a display. The interest region information managing means 130 automatically enlarges the size of the interest region until the measured communication rate reaches the first threshold.

Description

  The present invention relates to a moving image communication system, and more particularly to a moving image communication system in which an image quality of a specific area is higher than that of other areas and an image is transferred from a transmission apparatus to a reception apparatus via a communication network.

  An example of this type of video communication system is described in Patent Document 1. The moving image communication system described in Patent Document 1 includes a transmission device that transmits image data to a communication network and a reception device that receives and displays image data via the communication network. The transmission device or the reception device has an area designating unit for designating an arbitrary area in the image. The user designates a region of interest in the image by the region designation means. A region of interest is called a region of interest (ROI). The transmission device generates image data from the transmission target image so that the image quality of the region of interest is higher than that of the other regions, so that even if the transmission capacity of the communication network is small, it is possible to transmit the partial image in detail. Like that. Specifically, the transmission device calculates the image quality of the region other than the region of interest so as to satisfy the allowable transmission capacity of the communication network. In addition, if it is necessary to further reduce the transmission amount, the transmission device makes the image quality of the region of interest lower than that specified.

  A moving image communication system similar to Patent Document 1 is also described in Patent Document 2.

JP 7-288806 A JP-A-2005-341076

  In the moving image communication system described in Patent Literature 1 and Patent Literature 2, the image quality of the region other than the region of interest is reduced, and if it is still insufficient, the image quality of the region of interest is reduced, thereby allowing the allowable transmission of the communication network. The capacity is satisfied. For this reason, when the user makes a change to increase the size of the region of interest, a situation often occurs where the image quality of the entire region of interest suddenly decreases. From the user's point of view, when the area of interest is enlarged in order to display the surrounding area clearly, the entire area of interest, including the part that was clearly displayed before the change, becomes unclear. I could not say.

  An object of the present invention is to provide a moving image communication system that solves the problem that the image quality of the entire region of interest may suddenly deteriorate when the transmission amount of moving images is suppressed.

A moving image communication system according to an aspect of the present invention includes a transmission device and a reception device connected via a communication network, and the transmission device communicates with the reception device through the communication network. And a communication rate measuring means for measuring the communication rate of the transmitting communication means, and information relating to a region of interest set in a frame of a moving image, and when the measured communication rate reaches a first threshold A region-of-interest information management means for reducing the size of the region of interest, and generating image data from a frame image of the moving image so that the image quality of the region of interest is higher than that of other regions, Transfer image generating means for transmitting to the receiving device, and the receiving device is configured to receive side communication means for communicating with the transmitting device through the communication network. Screen display means for displaying a moving image based on the image data received by the receiving communication means on the display, and the region of interest information management means until the measured communication rate reaches the first threshold value. The size of the region of interest is automatically enlarged.

  Since the present invention is configured as described above, the image quality of the entire region of interest is not suddenly reduced when the transmission amount of moving images is suppressed, and usability is improved.

It is a block diagram of a 1st embodiment of the present invention. It is a block diagram of the 2nd Embodiment of this invention. It is a flowchart which shows the process example of the server in the 2nd Embodiment of this invention. It is a flowchart which shows the process example of the server in the 2nd Embodiment of this invention. It is a flowchart which shows the process example of the client in the 2nd Embodiment of this invention. It is a flowchart which shows the process example of the client in the 2nd Embodiment of this invention. It is a figure which shows an example of the display screen of the client in the 2nd Embodiment of this invention.

Next, embodiments of the present invention will be described in detail with reference to the drawings.
[First embodiment]
Referring to FIG. 1, the moving image communication system according to the first embodiment of the present invention includes a transmission device 100 and a reception device 200 connected via a communication network 300.

  The transmission apparatus 100 includes a communication unit 110, a communication rate measurement unit 120, a region-of-interest information management unit 130, and a transfer image generation unit 140. The receiving apparatus 200 includes a communication unit 210 and a screen display unit 220. Each of these has the following functions.

  The communication unit 110 has a function of communicating with the receiving device 200 wirelessly or by wire through the communication network 300.

  The communication rate measuring unit 120 has a function of measuring the communication rate of the communication unit 110. The communication rate means the amount of data transferred per unit time, and the unit is bps. The communication rate measuring unit 120 measures the communication rate mainly from the amount of data per unit time transmitted from the transmission device 100 to the reception device 200. In addition, the communication rate measuring unit 120 holds the first threshold value. The first threshold means the amount of data that can be transferred per unit time, and its unit is bps. Further, the communication rate measuring unit 120 compares the measured communication rate with the first threshold value, and when detecting that the communication rate has reached the first threshold value, notifies the region-of-interest information management unit 130 to that effect. It has a function.

  The region-of-interest information management unit 130 holds information about the region of interest set in the frame of the moving image. The shape of the region of interest is arbitrary. For example, the shape of the region of interest is a rectangle. When the region of interest is a rectangle, the information on the region of interest includes, for example, the XY coordinate value of the upper left corner point and the XY coordinate value of the lower right corner point of the rectangle on the frame. The region-of-interest information management unit 130 has a function of reducing the size of the region of interest when receiving a notification from the communication rate measuring unit 120 that the communication rate has reached the first threshold value. The width for reducing the size of the region of interest is arbitrary. The amount may be reduced by a fixed amount, or may be reduced by an amount that changes according to the amount by which the communication rate exceeds the first threshold. When the region of interest is a rectangle, the vertical and horizontal widths may be reduced, or only the vertical width or only the horizontal width may be reduced.

  The transfer image generation unit 140 generates image data from the frame image of the moving image, encodes it as necessary, and transmits it to the receiving apparatus 200 through the communication unit 110. The frame image of the target moving image is an image displayed on the screen of a computer constituting the transmission apparatus 100, for example. Further, the frame image of the target moving image may be an image other than the image on the screen, such as a moving image captured by a television camera connected to the transmission device 100. The transfer image generation unit 140 refers to the information about the region of interest held in the region of interest information management unit 130, and obtains image data from the frame image of the moving image so that the image quality of the region of interest is higher than other regions. Generate.

  In this specification, high image quality means that either one or both of spatial resolution and temporal resolution are high. Spatial resolution means the number of pixels per unit area, the number of colors of a color image, the resolution of the amplitude of a frequency signal obtained by frequency conversion of image data, the resolution of the amplitude of pixel data, and the quantum used when quantizing the pixel data. It means one, a plurality or all of the increments. The temporal resolution means one or both of the frame rate and the number of interlaces.

  The communication unit 210 of the reception device 200 has a function of communicating with the transmission device 100 wirelessly or by wire through the communication network 300.

  The screen display means 220 has a function of decoding the image data received by the communication means 210 as necessary and displaying it on the display.

  Next, the operation of this embodiment will be described.

  When a frame image of a moving image is input from a screen capture unit (not shown) or the like, the transfer image generation unit 140 of the transmission apparatus 100 refers to the information on the region of interest held in the region of interest information management unit 130, and the region of interest Image data is extracted from the frame image so that the image quality of the image becomes higher than that of the other areas, encoded as necessary, and transmitted to the receiving apparatus 200 via the communication unit 110. The transfer image generation unit 140 repeats the above-described operation every time a moving image frame image is input.

  The communication rate measuring unit 120 measures the communication rate of the communication unit 110 at regular intervals, for example, and compares it with the first threshold value. Then, when it is detected that the communication rate has reached the first threshold, it notifies the region-of-interest information management means 130 to that effect. Upon receiving this notification, the region-of-interest information management unit 130 updates information on the region of interest held by itself and reduces the size of the region of interest.

  When a frame image of a new moving image is input to the transfer image generation unit 140 after the size of the region of interest is reduced, the transfer image generation unit 140 extracts image data with reference to the reduced region of interest and performs communication. The data is transmitted to the receiving device 200 via the means 110. Since image data is generated so that the image quality of the region of interest is higher than that of other regions, the amount of image data per frame is reduced by reducing the size of the region of interest. For this reason, it becomes possible to control the communication rate of the communication means 110 so as not to exceed the first threshold value by reducing the size of the region of interest.

  On the receiving device 200 side, the image data transmitted from the transmitting device 100 is received by the communication unit 210, and the screen display unit 220 decodes it as necessary and displays it on the display. As a result, a moving image whose region of interest has a higher image quality than other regions is displayed on the display of the receiving apparatus 200. In addition, when the communication rate of the communication unit 210 reaches the first threshold due to an increase in the information amount of the moving image, the size of the region of interest in the image displayed on the receiving device 200 is reduced, but the entire region of interest A situation where the image quality suddenly deteriorates does not occur.

[Second Embodiment]
Next, an embodiment in which the present invention is applied to a screen transfer / remote operation system will be described. The screen transfer / remote control system transfers the server (PC) side screen to the client (PC, mobile phone terminal, etc.) side by communication and displays it. This system remotely operates the server side by transmitting operation information.

[Description of configuration]
First, the configuration of the present embodiment will be described in detail with reference to the drawings. FIG. 2 is a system configuration diagram of the present embodiment. The screen transfer / remote operation system according to the present embodiment includes a server 1, a client 2, and a communication network 3.

  The server 1 includes screen capture means 11, transfer image generation means 12, communication means 13, ROI range information management means 14, and communication rate measurement means 15.

  The screen capture unit 11 captures the server-side screen at a certain period to obtain an image.

  The transfer image generation unit 12 converts the image obtained by the screen capture unit 11 into a format suitable for transfer to the client 2. As a conversion method, compression or encoding is generally used. Many methods of compression and encoding are generally known. This embodiment can use these general compression and encoding techniques. Further, when generating the transfer image, the transfer image generation unit 12 sets only a region (for example, a region specified by the XY coordinates) notified as the ROI range from the ROI range information management unit 14 to high image quality. The image quality is low outside the area. As a means for changing the image quality (resolution / code amount) within and outside the specific range as described above, JPEG2000 and Flash Pix are generally used. In this embodiment, those general means can be used. The shape of the ROI range may be a circle, an ellipse, or a rectangle as long as the image quality changing means within the specific range permits technically.

  The communication unit 13 transmits the transfer image data generated by the transfer image generation unit 12 to the client 2 via the communication network 3. The communication unit 13 transmits intermediate rate over information (described later) received from the communication rate measurement unit 15 to the client 2 via the communication network 3. The communication unit 13 transmits the ROI range reduction information received from the ROI range information management unit 14 to the client 2 via the communication network 3. Further, the communication means 13 receives remote operation input information and ROI range information transmitted from the client 2 side.

  The communication rate measuring means 15 monitors the communication rate by the communication means 13, and when the first threshold value preset in the own means 15 is reached, notifies the ROI range information management means 14 to that effect and Notification is made to the client 2 side through the means 13. The first threshold is set to an upper limit value (hereinafter referred to as an upper limit rate) of a band that can be used by the communication unit 13 for transmission to the client 2. Further, the communication rate measuring means 15 notifies the intermediate rate over information to the client 2 side through the communication means 13 when the communication rate by the communication means 13 reaches the second threshold value preset in the own means 15. The second threshold is set to half of the upper limit rate (hereinafter referred to as the intermediate rate). However, setting the second threshold value to half of the upper limit rate is merely an example, and can be arbitrarily determined in consideration of user convenience. In addition, the upper limit rate value that is the first threshold value and the intermediate rate value that is the second threshold value may be changed from time to time by the server 1, the client 2, and the communication network 3 (communication service provider / provider). .

  The ROI range information management unit 14 receives the ROI range information from the client 2 via the communication unit 13, stores it in itself, and notifies the transfer image generation unit 12 of it. When the ROI range information management unit 14 receives a notification from the communication rate measurement unit 15 that the communication rate has reached the upper limit rate, the ROI range information management unit 14 converts the current ROI range information stored in itself into a smaller ROI range. In addition to updating the information, the ROI range reduction information is transmitted to the client 2 through the communication means 13. When the ROI range information management means 14 updates the ROI range information to the ROI range information having a smaller size, for example, if the ROI range is a rectangle, the vertical and horizontal lengths of the rectangular ROI range are directed toward the center. Use a method of shortening by several dots. Further, the ROI range information management unit 14 ignores the ROI range information for enlarging the size of the ROI range passed from the client 2 via the communication unit 13 for a certain time after receiving the notification of reaching the upper limit rate. However, the ROI range information management unit 14 accepts the ROI range information for reducing the size or changing the position of the ROI range passed from the client 2 via the communication unit 13 and notifies the transfer image generation unit 12 of it.

  The client 2 includes screen display means 21, communication means 22, input means 23, and ROI range information control means 24.

  The screen display means 21 displays the transfer image sent from the server 1 side via the communication means 22. At this time, the screen display means 21 displays it after decompressing and decoding if compression and encoding are performed on the server 1 side. The screen display means 21 refers to the ROI range information control means 24, confirms the position of the ROI range and the color of the frame, and draws the frame indicating the ROI range in the above color.

  The communication unit 22 delivers the image information transferred from the server 1 via the communication network 3 to the screen display unit 21. The communication unit 22 receives the ROI range reduction information and the intermediate rate over notification from the server 1 and passes them to the ROI range information control unit 24. Further, the communication unit 22 transmits the remote operation information passed from the input unit 23 and the ROI range information passed from the ROI range information control unit 24 to the server 1 via the communication network 3.

  The input unit 23 receives remote operation information of the server 1 by a mouse input or a key input from a user and passes it to the communication unit 22. The input means 23 also receives an input from the user for setting or changing the ROI range. For example, when two points are designated on the client 2 screen by a mouse operation or the like, the input unit 23 accepts a setting in which a rectangle having the two points as the upper left end point and the right lower end point is set as the ROI range. For example, the input unit 23 accepts an operation of dragging and drawing a frame of the ROI range drawn on the client 2 screen with a mouse as an operation of changing the position and size of the ROI range. The input unit 23 notifies the ROI range information control unit 24 when there is a change in the ROI range.

  The ROI range information control unit 24 updates the ROI range information in the client 2 when receiving a setting change request for the ROI range from the input unit 23 and when receiving the ROI range reduction information from the communication unit 22. When the ROI range information control means 24 receives the notification that the communication rate has reached the upper limit rate and the ROI range reduction information from the server 1 via the communication means 22, the ROI range information control means 24 from the input means 23 for a certain period. Ignores the request to enlarge the size of the notified ROI range (accepts position movement and range reduction). Further, when the ROI range information control unit 24 receives an intermediate rate over notification from the server 1 via the communication unit 22, the ROI range information control unit 24 updates the color of the frame of the ROI range. As a result, it is possible to visually tell the user how much the communication rate can afford to reach the upper limit.

  The communication network 3 may be arbitrary as long as the server 1 and the client 2 can communicate with each other. The communication network 3 may be wired or wireless, and any communication network such as a 3G network, an Ethernet (registered trademark) network, or a WMAX network may be used.

[Description of operation]
Next, the operation of this embodiment will be described with reference to the flowcharts of FIGS. 3, 4, 5, and 6.

  First, the operation on the server side will be described with reference to FIGS. Note that the process shown in FIG. 3 and the process shown in FIG. 4 operate in parallel.

  Referring to FIG. 3, the server 1 first captures the server side screen by the screen capture unit 11 (S1-4). Next, the transfer image generation unit 12 refers to the ROI range information management unit 14 to confirm the ROI range information (S1-2), and generates high-quality transfer image data only within the ROI range (S1-3). Next, the image data generated by the communication means 13 is transmitted to the client (S1-4). These processes are repeated periodically (for example, every frame period) while using the screen transfer / remote control system.

  The process of FIG. 4 is repeated periodically while the screen transfer / remote operation system is used as in the process of FIG. First, the communication rate measuring unit 15 of the server 1 determines whether or not the communication rate of the communication unit 13 has reached the upper limit rate (S2-1). If the maximum rate has been reached, proceed to S2-2, S2-3, S2-4, S2-5, and if the maximum rate has not been reached, S2-6, S2-7, S2 -8, go to S2-9 flow.

  If the upper limit rate has been reached, the communication rate measuring means 15 transmits an upper limit arrival notification to the client 2 (S2-2). Next, the communication rate measuring means 15 notifies the ROI range information managing means 14 that the upper limit has been reached, and the ROI range information managing means 14 updates the ROI range to a reduced version and notifies the client (S2-3). Further, the ROI range information management means 14 monitors whether or not the ROI range information is notified from the client 2 via the communication means 13 (S2-4). When the ROI range information notification is received from the client 2, the ROI range information management means 14 analyzes the notification content, and if the ROI range is reduced, and the position movement information is received, the ROI range information is notified. Update the information (S2-5). On the other hand, if the ROI range information management means 14 is a notification of the enlargement of the size of the ROI range, the notification is ignored and the ROI range information is not updated (S2-5).

  If the upper limit rate has not been reached, the communication rate measuring means 15 determines whether or not the communication rate of the communication means 13 has reached the intermediate rate (S2-6). If the communication rate becomes half of the upper limit value, the communication rate measuring means 15 notifies the client 2 to that effect (S2-7). In addition, the ROI range information management unit 14 monitors whether or not the ROI range information is notified from the client 2 via the communication unit 13 (S2-8). When the ROI range information is notified from the client 2, the ROI range information management unit 14 updates the ROI range information as notified (S2-9). That is, since the upper limit value of the communication rate has not been reached, the ROI range information management unit 14 accepts all requests including the notification of the size increase of the ROI range and updates the ROI range information on the server 1 side.

  Next, the operation on the client side will be described with reference to FIGS. Note that the processing shown in FIG. 5 and the processing shown in FIG. 6 operate in parallel.

  Referring to FIG. 5, when the communication unit 22 of the client 2 receives the transfer screen (S3-1), the screen display unit 21 displays the transfer screen on the display (S3-2). Subsequently, the screen display unit 21 refers to the ROI range information held by the ROI range information control unit 24, confirms the position of the ROI range and the color of the frame, and draws the frame of the ROI range on the display (S3). -3). These processes are repeated periodically when using the screen transfer / remote control system.

  The process of FIG. 6 is repeated periodically while the screen transfer / remote control system is used, as in the process of FIG. When the upper limit rate arrival notification and the ROI range reduction information reach the communication means 22 and within a certain time after reaching the client 2, the client 2 performs S4-2, S4-3, S4-4, and S4-5. Proceed to the flow, and if not within a certain time, proceed to the flow of S4-6, S4-7, S4-8, S4-9, S4-10.

  When the upper limit rate arrival notification and the ROI range reduction information reach the communication means 22, the ROI range information control means 24 updates the ROI range information held by itself according to the reached ROI range reduction information (S4-2). ). Further, the ROI range information control unit 24 monitors whether or not a notification for changing the ROI range is received from the input unit 23 (S4-3). Then, when a notification for changing the ROI range comes from the input means 23, the ROI range information control means 24 analyzes the notification contents, and if the notification is for the reduction of the ROI range and the change of the position, the ROI range information is changed. Information is notified to the server 1 via the communication means 22 (S4-4), and the ROI range information held in the own means 24 is updated as notified (S4-5). On the other hand, if the ROI range information control means 24 is a notification of expansion of the ROI range, the ROI range information control means 24 ignores the notice and does not update the ROI range information held in the server 1 and the own means 24.

  In addition, when the upper limit rate arrival notification and the ROI range reduction information are not in a certain period after reaching the communication means 22, the ROI range information control means 24 receives a notification from the server 1 that it has reached half of the upper limit rate. (S4-6). If such notification is received, the ROI range information control unit 24 changes the color of the frame in the ROI range information held by itself to a predetermined color (for example, yellow) (S4-7). Further, the ROI range information control means 24 monitors whether or not a notification for changing the ROI range has been received from the input means 23 (S4-8). When a notification for changing the ROI range is received from the input unit 23, the ROI range information control unit 24 analyzes the content of the notification and notifies the server 1 of the changed ROI range information via the communication unit 22 ( S4-9), as notified to the server 1, the ROI range information held in the own means 24 is updated (S4-10). The ROI range information control means 24, when the change in the ROI range is a reduction of the ROI range, and the frame color in the ROI range information is yellow, The color is changed from yellow to a normal color (for example, blue).

  FIG. 7 shows a display example of the display screen of the client 2. The text displayed on the screen of the server 1 is transferred to the client 2 by screen transfer, and shows a situation where the user is reading the text while scrolling (display on the upper left). However, since it is only necessary to read the text only in the selected area (ROI range) within the dotted line that appears newly by scrolling, the image quality is reduced outside the ROI range by reducing the communication volume so that the response will be better (upper right corner) Display of). When the amount of information increases and the communication rate reaches half of the upper limit, a notification is received from the server 1 and the color of the ROI range frame changes (displayed in the lower left). Furthermore, when the communication rate reaches the upper limit value, the server 1 forcibly reduces the ROI range by one (display on the lower right). Even if the ROI range is reduced, the bottom line is included in the ROI range, so it is possible to read the newly appearing characters by scrolling.

  The example of FIG. 7 is an example of screen transfer for reading text, but it can also be applied to the case where, for example, the text creation application of the server 1 is started from the client 2 and the character input screen of the application is transferred to input characters. . In this case, if only the vicinity where characters are newly input can be viewed with high image quality, the work will not be hindered. Furthermore, application to fields other than text input is also possible.

[Description of effects]
Next, the effect of this embodiment will be described.

  According to the present embodiment, it is possible to prevent the image quality of the entire ROI range from being suddenly lowered. The reason for this is that when the communication rate reaches the upper limit rate, the server 1 of this embodiment forcibly reduces the ROI range for screen transfer with high image quality, so that the transmission rate from the server 1 is set to the upper limit rate. This is because it is not exceeded. That is, unlike in Patent Document 1 and Patent Document 2, the transmission rate of the server 1 is not adjusted by reducing the image quality in the ROI range.

  Moreover, according to this embodiment, it becomes possible to prevent the situation where a response deteriorates. The reason for this is that when the communication rate reaches the upper limit rate, the server 1 of this embodiment forcibly reduces the ROI range for screen transfer with high image quality, so that the transmission rate from the server 1 is set to the upper limit rate. This is because it is not exceeded.

  Further, according to the present embodiment, it is possible to provide the user with an indication of how much the ROI range can be expanded from the current state. The reason is that when the communication rate reaches the upper limit rate and the ROI range cannot be expanded, the ROI range frame is displayed in red to indicate that, for example, and when the communication rate reaches the intermediate rate, the ROI range frame This is because, for example, yellow is displayed to indicate that, and when the communication rate does not reach the intermediate rate, the frame of the ROI range is displayed, for example, blue indicating that.

[Other embodiments]
Although the present invention has been described with reference to some embodiments, the present invention is not limited to the above embodiments, and various other additions and modifications can be made. For example, the following embodiments are also included in the present invention.

  In the above explanation, the function to perform automatic adjustment to automatically reduce the size of the ROI range only when the transmission rate reaches the upper limit value was described. However, when the upper limit value has not been reached, the ROI range is automatically changed. An embodiment in which the size is enlarged (third embodiment) is also possible. In the third embodiment, the user designates the center position of the ROI range from the input means 23. The center position of the ROI range designated by the user is stored in the ROI range information control unit 24 and is notified to the server 1 and stored in the ROI range information management unit 14. The ROI range information management unit 14 expands the ROI range from the center position toward the periphery until either the transmission rate of the communication unit 13 reaches the upper limit value or the entire server screen is in the ROI range. For example, when the center of the ROI range is specified by a small rectangle, the vertical and horizontal lengths of the rectangle are increased outward by several dots, and further expansion is stopped for the side that reaches the screen edge. Let Thus, in the third embodiment, the user operates only the position of the ROI range, and the size is always automatically adjusted.

  Further, an embodiment (fourth embodiment) having a function of transferring only the update difference area whose screen has changed on the server side to the client is also possible. According to the fourth embodiment, it is possible to specify a large ROI range without increasing the communication rate at a timing when the screen update is small. In the fourth embodiment, when the user moves or changes the size of the ROI range, the image portion of the screen range newly added as the ROI range is updated even if it is not actually updated. Is transferred to the client with high image quality. As a result, even if there is no change in the server-side screen, if the user gradually moves the ROI range or increases the size, the screen range that can be viewed with high image quality will move and expand accordingly. It will be.

  In the above description, the upper limit rate is a fixed value set in advance, but an embodiment (fifth embodiment) in which the upper limit rate is a variable value is also possible. For example, it is possible to provide a function for automatically determining the currently available bandwidth on the server 1 side, and the bandwidth determined by this function can be used for the upper limit route.

  In the above description, the embodiment in which the present invention is applied to a screen transfer / remote operation system has been described as an example. However, if the system transfers an image from a transmission device such as a server to a reception device such as a client, the screen is displayed. The present invention is not limited to transfer / remote operation systems.

  Further, the transmission device and the reception device of the present invention can realize the functions of the above embodiments by a computer and its program. The program is provided by being recorded on a computer-readable recording medium such as a semiconductor memory or a magnetic disk, and read by the computer at the time of starting up the computer, etc., and controlling the operation of the computer. Function as a transmission device, a server, a reception device, and a client.

DESCRIPTION OF SYMBOLS 1 Server 2 Client 3 Communication network 11 Screen capture means 12 Transfer image generation means 13 Communication means 15 Communication rate measurement means 21 Screen display means 22 Communication means 23 Input means 24 Client 24 Own means 100 Transmitter 110 Communication means 120 Communication rate measurement means 130 Region of Interest Information Management Unit 140 Transfer Image Generation Unit 200 Receiving Device 210 Communication Unit 220 Screen Display Unit 300 Communication Network

Claims (5)

Consists of a transmission device and a reception device connected via a communication network,
The transmitter is
Transmitting-side communication means for communicating with the receiving device through the communication network;
Communication rate measuring means for measuring the communication rate of the transmitting communication means;
Region-of-interest information management means for holding information on a region of interest set in a frame of a moving image and reducing the size of the region of interest when the measured communication rate reaches a first threshold;
Transfer image generation means for generating image data from a frame image of a moving image so that the image quality of the region of interest is higher than other areas, and transmitting the image data to the reception device by the transmission side communication means,
The receiving device is:
Receiving-side communication means for communicating with the transmitting device through the communication network;
Screen display means for displaying a moving image based on the image data received by the receiving side communication means on a display;
The moving image communication system according to claim 1, wherein the region of interest information management means automatically enlarges the size of the region of interest until the measured communication rate reaches a first threshold value. The receiving device is:
An input means for inputting a request for setting and changing a region of interest from a user;
Analyzing the inputted request for setting and changing the region of interest, generating information on the latest region of interest, holding the generated information on the region of interest, and transmitting the information to the transmitting device by the receiving side communication means And a region-of-interest information control unit that updates the held information when the information on the reduced region of interest is received by the receiving-side communication unit,
The moving image communication system according to claim 1, wherein the region-of-interest information management unit of the transmission device holds information regarding the region of interest received from the reception device by the transmission-side communication unit. 3. The transfer image generation means transmits only a changed update difference area of image data generated from a frame image of a moving image to the reception device by the transmission side communication means. The moving image communication system described. A transmission method executed by a transmission device having a communication unit, a communication rate measurement unit, a region of interest information management unit, and a transfer image generation unit,
The communication rate measuring means measures the communication rate of the communication means;
The region-of-interest information management means reduces the size of the region of interest set in a frame of a moving image when the measured communication rate reaches a first threshold;
The region-of-interest information management means automatically increases the size of the region of interest until the measured communication rate reaches a first threshold;
The transfer image generation means generates image data from the frame image of the moving image so that the image quality of the region of interest is higher than other regions;
The transmission method, wherein the communication means transmits the generated image data to a receiving device connected via a communication network. Computer
Communication means for communicating with the receiving device through a communication network;
Communication rate measuring means for measuring a communication rate of the communication means;
Information on a region of interest set in a frame of a moving image is held, and the size of the region of interest is reduced when the measured communication rate reaches a first threshold, and the measured communication rate is the first Region of interest information management means for automatically expanding the size of the region of interest until a threshold value of
A program for generating image data from a frame image of a moving image so that the image quality of the region of interest is higher than that of other regions, and causing the communication unit to function as a transfer image generation unit that transmits the image data to the reception device.

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