JP2011091614A - Image encoder, and image processing system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an encoding technique capable of improving encoding efficiency without degrading image quality, reducing a load on an encoding process, and satisfying a demand related to a real-time property. <P>SOLUTION: Camera angles of a plurality of cameras directed to imaging objects are acquired to identify the imaging object for every camera; a pertinent encoding parameter is read from an encoding parameter table with encoding parameters corresponding to the imaging objects stored therein; and an encoding process for every camera image is performed to output encoding data. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an image encoding device and an image processing system, and, for example, relates to a moving image encoding technique.

  In recent years, in the field of transmitting and receiving images between devices connected via a network, such as telemedicine and remote monitoring, multiple camera images can be simultaneously transmitted with the aim of more accurately telling the receiver of the situation and realism. In addition to the use of multi-angles, there is a growing demand to use individual camera images with large screens and high resolution images.

  For example, the telemedicine support system is used by a doctor B who treats a patient A to advance medical practice while exchanging information with a doctor C who is monitoring the state of treatment of the patient A by video at a remote place. . The remote monitoring system is used to perform facility maintenance, crime prevention activities, disaster countermeasures, and the like while viewing images from a plurality of surveillance cameras installed at remote locations. These systems require the same quality of camera images, and in the future, in order to accurately determine the situation at the site and smoothly perform related work, the camera images will be further multi-angled and the moving images will be of higher definition. Expected to go forward.

  Regarding moving image encoding, for example, Patent Documents 1 and 2 disclose a method of changing camera imaging conditions and encoding parameters (image size, compression rate, number of frames) according to the characteristics of a subject to be captured for each camera video. Has been. Patent Document 3 discloses a method for changing the image quality setting for each predetermined image area (in the spatial direction and the time direction) based on the attention area information of the image.

JP 2001-211450 A JP 2009-105956 A JP 2006-80832 A

"Video Standard Coding (MPEG)", Kazuo Ozeki, MEDICAL IMAGING TECHNOLOGY Vol.14 No.3, pp237-242 (May 1996) "Acceleration of rate-distortion optimization mode judgment in H.264", Akiyuki Yazawa, Shinichiro Furuto, Ken Nakatsuji, IEICE Transactions D Vol.J89-D NO1 pp.27-39 (2005 7 Moon)

  Simultaneous transmission and reception of a plurality of large-capacity video data has a problem in that a communication band increases, a load is applied to the network, and a failure such as a decrease in frame rate occurs. In order to avoid this, there is an example in which the amount of video data is compressed using a moving image compression encoding technique (for example, H.264 / AVC).

  However, when the compression rate of video data is increased, there is a problem that a reduction in video quality is inevitable. In particular, in applications such as telemedicine and remote monitoring, the content of the video cannot be accurately grasped due to a drop in video quality, which may hinder work. In order to prevent deterioration in video quality, when encoding and transmitting a plurality of images (images from a plurality of cameras), it is conceivable to encode and transmit while switching the cameras. However, such a method may not be able to transmit an originally required image, and cannot satisfy the needs sufficiently in a system that requires real-time performance, such as monitoring and a medical system.

  Further, it is generally known that video coding requires heavy processing load because it requires a large amount of signal processing operations. In order to obtain optimal encoding parameters that match the user's operating conditions, it is necessary to increase the amount of calculation for encoding processing below the GOP layer, leading to an increase in the cost of the image encoding apparatus. However, since the techniques described in Patent Documents 1 to 3 are for monitoring devices that require cost reduction, the image size, compression rate, number of frames, etc., are avoided in order to avoid a significant increase in the amount of encoding calculation. It only changes the coding parameters at the sequence layer level.

  The present invention has been made in view of such a situation, and is capable of improving encoding efficiency without reducing image quality, reducing the burden of encoding processing, and satisfying a request regarding real-time characteristics. Providing technology.

  In order to solve the above-described problem, in the present invention, the camera angle information of a plurality of cameras directed to a shooting target is acquired, the shooting target for each camera is specified, and the encoding parameter corresponding to the shooting target is stored. The corresponding encoding parameter is read from the encoding parameter table, the encoding process is performed for each camera image, and the encoded data is output. Note that the encoding parameters may be read from the table or may be determined one by one according to the characteristics of each image to be encoded.

  That is, the image encoding device according to the present invention acquires shooting target specifying information for specifying a target to be shot by each of a plurality of cameras from each camera, and shooting of each camera based on the shooting target specifying information. A plurality of encoding parameters (optimal encoding parameters) corresponding to the shooting target of each camera are acquired most efficiently in identifying the target and encoding an image from each camera. Then, the image encoding device uses the acquired plurality of encoding parameters to encode each continuous image of each subject to be sent from each camera (an image continuous from each camera instead of time division). Is encoded), and encoded data for each subject is generated, each encoded data is multiplexed, and the multiplexed data is output. Here, the shooting target specifying information includes information of a set angle (camera height if necessary) with respect to the shooting target of each camera, and the camera angle with respect to each camera based on an input instruction from the user. A setting signal is transmitted, and each camera is controlled so as to be able to photograph a desired subject.

  The encoding parameter is generated based on the characteristics of the image to be imaged, and includes information on an encoding mode, a quantization parameter, a macroblock size, and a motion vector search range when the imaged object is encoded.

  In addition, according to the present invention, an image encoding device that encodes and transmits images captured by a plurality of cameras, and an image decoding device that decodes the transmitted encoded data and outputs the decoded data to a monitor are provided. It can also be constructed as an image processing system. In this case, the image encoding device acquires shooting target specifying information for specifying a target to be shot by each of the plurality of cameras from each camera, and the shooting target of each camera based on the shooting target specifying information. Is identified. Then, the image encoding device, for each shooting target corresponding to the shooting target of each camera, from the encoding parameter table that stores the most efficient encoding parameters for encoding the shooting target image, respectively, A plurality of encoding parameters corresponding to the shooting target of each camera, and using the plurality of encoding parameters, a continuous image of each shooting target sent from each camera is encoded, Encoded data is generated, and each encoded data and each encoding parameter corresponding to the object to be imaged are multiplexed to generate multiplexed data. This multiplexed data is transmitted to the image decoding apparatus. On the other hand, the image decoding apparatus receives the multiplexed data, performs a decoding process on the encoded data for each imaging target included in the multiplexed data using a corresponding encoding parameter, and The decoded image is generated, and the decoded image for each subject is output to the monitor.

  Note that when the number of cameras connected to the image encoding device is larger than the number of monitors connected to the image decoding device, the decoding process of the decoded image for each shooting target is executed, and all the decoding is performed on the monitor. Allow images to be displayed.

  Further, each of the image encoding and decoding devices may be provided with an input unit for inputting angle settings with respect to the imaging targets of a plurality of cameras. Then, the angles of the plurality of cameras are adjusted based on the angle setting information input from each input unit.

  Further features of the present invention will become apparent from the best mode for carrying out the present invention and the accompanying drawings.

  According to the present invention, it is possible to provide an encoding technique capable of improving encoding efficiency without reducing image quality, reducing the burden of encoding processing, and satisfying a request regarding real-time characteristics.

It is a figure which shows schematic structure of the image coding apparatus by embodiment of this invention. It is a figure for demonstrating the transmission procedure of a camera angle acquisition signal. It is a figure for demonstrating the definition of a camera angle. It is a figure for demonstrating the outline | summary of the process which determines an encoding parameter and encodes an image | video. It is a figure which shows the content of the encoding parameter table. It is a figure which shows an example of an encoding parameter. It is a figure which shows schematic structure of the image decoding apparatus by embodiment of this invention. It is a figure for demonstrating the procedure which sets the camera angle of a several camera. It is a figure which shows the example which displays the camera image for several units | sets on a monitor. It is a flowchart for demonstrating an image encoding process. It is a flowchart for demonstrating an image decoding process. It is a figure which shows an example of operation | movement of the system which uses an image coding and decoding apparatus.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be noted that this embodiment is merely an example for realizing the present invention and does not limit the technical scope of the present invention. In each drawing, the same reference numerals are assigned to common configurations.

<Configuration of Image Encoding Device>
FIG. 1 is a diagram showing a schematic configuration of an image encoding device 100 according to an embodiment of the present invention. The image encoding apparatus 100 is connected to a plurality of cameras 1 to N (107, 108 to 109), and transmits a camera angle setting signal 112 to each camera to set a shooting angle, or from each camera. A camera control unit 102 for receiving the camera angle acquisition signal 113; an encoding parameter table 105 that stores in advance encoding parameters corresponding to each object to be imaged so that the encoding processing load can be reduced; An encoding control unit 104 for performing control to read out encoding parameters corresponding to the imaging target from the table 105, and an encoding parameter read by the encoding control unit 104 for the captured video of each camera An encoding unit 103 that performs encoding (for example, in a method compliant with H.264) and then multiplexes into one encoded data; From the camera angle acquisition signal 113 and the transmission / reception unit 1 (106) for receiving the camera angle setting signal 112 for each camera transmitted to the image decoding apparatus 114 via the network or transmitted from the image decoding apparatus 114. An overall encoding control unit 101 is provided for specifying an imaging target for each camera and for overall control of the operation of each unit.

  The image encoding device 100 and the image decoding device 114 are connected via, for example, a network. The image encoding device 100 is connected to a monitor 1 (111) for displaying a video signal 111 output from each camera. Similarly, a monitor 2 (115) for displaying a video signal is also connected to the image decoding apparatus 114.

<Camera angle acquisition signal>
FIG. 2 is a diagram for explaining the transmission procedure of the camera angle acquisition signal 113. The camera control unit 102 receives a camera angle acquisition signal 113 indicating the shooting angle of the camera from the N cameras 107 and 108 to 109 connected to the image encoding device 100 and transmits the received camera angle acquisition signal 113 to the overall encoding control unit 101. The camera angle is an angle of the camera in the horizontal direction and the vertical direction with respect to a predetermined horizontal reference line or vertical reference line. Then, the encoding overall control unit 101 specifies the imaging target for each camera from the camera angle acquisition signal 113, and encodes the imaging target region information (θ1, θ2, h) 200 indicating the specified object. To communicate. Here, θ1 and θ2 are the horizontal and vertical angles of the camera, and h is the installation height of the camera.

<Camera angle>
FIG. 3 is a diagram for explaining the definition of the camera angle. Here, a situation is described in which a person who is a subject of imaging is sleeping on his / her back on the examination table 303 and a part of the person's body is photographed with the camera facing the examination table.

  FIG. 3A is a diagram illustrating the definition of the camera angle in the horizontal direction. The camera 300 is arbitrarily installed at a position where the whole body of the person 301 can be seen, but it is assumed that the positions of the camera 300 and the examination table 303 are fixed at the start of imaging. The direction of the camera shall always be freely movable in the horizontal and vertical directions. In addition, the person 301 sleeps on his back inside the effective imaging area 302 set on the examination table 303. At this time, in order to specify which part of the body of the person 301 is photographed in the horizontal direction, the camera angle θ1 (304) in the horizontal direction with respect to the horizontal reference line 305 is measured.

  FIG. 3B is a diagram showing the definition of the camera angle in the vertical direction. The positional relationship among the camera 300, the examination table 303, and the person 301 is the same as in FIG. At this time, in order to specify which part of the body of the person 301 is photographed in the vertical direction, the camera angle θ2 (306) in the vertical direction with respect to the vertical reference line 307 is measured.

  The coordinates in the effective imaging region 302 can be specified from the information of the camera height h, the horizontal camera angle θ1, and the vertical camera angle θ2 (306). That is, the position of a certain point on the body of the person being photographed by the camera is specified from these pieces of information. If all the cameras have the same height, there is no need to set the height h again.

<Outline of encoding process>
FIG. 4 is a diagram showing a procedure for executing a camera video encoding process by determining an encoding parameter from the camera angle acquisition signal 113.

  The encoding control unit 104 receives the imaging target region information 400 from the overall encoding control unit 101, reads out an encoding parameter 401 used for encoding processing of the target region based on the information from the encoding parameter table, and performs encoding. To the conversion unit 103. Then, the encoding unit 103 generates and outputs encoded data 402 by executing the encoding process of the video signal 403 sent from the camera using the acquired encoding parameter 401.

  FIG. 5 is a diagram for explaining the encoding parameter table 105. FIG. 5A shows an example in which a symbol is assigned to each body part of the person 501. This symbol corresponds to the imaging target part information output from the overall encoding control unit 101. In the example in the figure, the head is defined as A (502), the left arm as B1 (503), the right arm as B2 (504), the abdomen as C (505), the left foot as D1 (506), and the right foot as D2 (507). is doing. FIG. 5B shows the contents (example) of the encoding parameter table 105.

  As shown in FIG. 5B, the encoding parameter table 105 has two items, a target part 514 and an encoding parameter 515. The item of the target part 514 stores a symbol indicating the part of the body of the person 501 shown in FIG. 5A, that is, imaging target part information. Further, the term of the encoding parameter 515 stores an encoding parameter suitable for encoding the video of the target part.

  The encoding control unit 104 compares the imaging target region information acquired from the overall encoding control unit 101 and the item of the target region 514 in the encoding parameter table 105, reads out the encoding parameter 515 at the location where both match, and performs encoding. To the conversion unit 103. If the imaging target part information and the item of the target part 514 of the encoding parameter table 105 do not match, the encoding control unit 104 notifies the encoding unit 103 that an error has occurred.

  In FIG. 5, the classification of the target part is roughly defined as an outline description. However, the part of the body of the person 501 may be classified in more detail, and encoding parameters corresponding to each part may be prepared.

  FIG. 6 is a diagram illustrating an example of the encoding parameter 606 stored in the encoding parameter table 105. There are various types of video encoding parameters. For example, the international standard H.264 for moving picture compression. In H.264 / AVC, encoding parameters for determining the overall configuration of video compression, such as image size and frame rate, are defined at the sequence layer level (hereinafter referred to as upper layer). On the other hand, layers below the sequence layer level include a GOP layer, a picture layer, a slice layer, and a macroblock layer (hereinafter referred to as a lower layer). In the lower layer, there is an encoding parameter for performing encoding for a subdivided image area in consideration of the image quality of the area. For example, there are an encoding mode 601, a quantization parameter 602, a macroblock size 603, and the like. The encoding parameter table 105 stores these parameters in advance.

  In general, in order to determine the optimum solution for the encoding parameters of these lower layers, it is necessary to find a parameter with the highest encoding efficiency while performing a predetermined calculation on the video data. In addition, it is known that the calculation processing for obtaining the optimum solution of the encoding parameter has a large calculation amount and a heavy processing load as it becomes a lower layer.

  Therefore, in order to reduce the processing load of encoding, the image encoding apparatus 100 according to the present invention sets in advance an encoding parameter optimal for encoding for each target region of imaging in the encoding parameter table 105, At the stage where the part to be imaged can be identified, the encoding parameter associated with the part is read out and applied to the encoding process. Note that the optimal encoding parameter can be obtained using the methods disclosed in Non-Patent Document 1 and Non-Patent Document 2, for example. That is, since the distribution (bias) of the frequency component differs depending on the body part, parameters suitable for encoding each part are obtained and the encoding process is executed. In this embodiment, an encoding parameter table is prepared. However, the present invention is not limited to this, and the encoding parameter may be calculated one by one after specifying a part. Alternatively, the encoding parameter may be obtained only for the corresponding part for the first time and the table may be completed sequentially.

  In order to reduce the encoding processing load, a motion vector search range 604 with a predetermined restriction can be set as an item of the encoding parameter 105. A motion vector search process is an example of an encoding process with a large processing load. The motion vector search is a calculation process for obtaining the direction and amount of movement of the target image, but it is necessary to compare the images of the two macroblocks with one pixel accuracy for all ranges in which the target image may move. Therefore, a large amount of iterative calculation is required.

  However, since the image coding apparatus 100 according to the present invention is intended for shooting an object that generates only a small amount of motion, even if a predetermined limit is set for the motion vector search range, the image quality after coding is not affected. However, the amount of calculation can be reduced without causing a major obstacle.

  The encoding parameter shown in FIG. 6 is an example, and other encoding parameters may be added and stored.

<Configuration of image decoding apparatus>
FIG. 7 is a diagram illustrating a schematic configuration of the image decoding device 114. The image decoding device 114 includes a transmission / reception unit 2 (702) for receiving encoded video data transmitted from the image encoding device 100, and a decoding for decoding the encoded data into an original video signal. Unit 700 and an overall decoding control unit 701 for performing overall control of operations of the respective units. The image decoding device 114 is connected to a plurality of monitors 703, 704 to 705, and the decoded video signal is displayed on each monitor. The video displayed on the monitor may be displayed so as to have a one-to-one relationship with a plurality of cameras connected to the image encoding device 100. Further, a plurality of videos may be aggregated and displayed on one monitor. The display form will be described later with reference to FIG.

  The decoding unit 700 performs a decoding process using the encoding parameter transmitted from the image encoding device 100. In this way, no special configuration is required for the image decoding apparatus. On the other hand, if the image decoding apparatus 114 includes a table similar to the encoding parameter table 105, there is no need to transmit the encoding parameter from the image encoding apparatus 100, so that the transmission code amount can be reduced. There is.

<Camera angle setting process>
FIG. 8 is a diagram illustrating a procedure for setting camera angles of a plurality of cameras connected to the image encoding device 100.

  The camera angles of the cameras 1 to N (107, 108 to 109) are adjusted by operating the input I / F 1 (interface) 800 of the image encoding apparatus 100 while viewing the video of the monitor 1 (110), Direction and vertical direction can be set.

  The camera angle setting information is transmitted to the camera control unit 102 via the overall encoding control unit 101. Then, the camera control unit 102 moves the angle adjustment mechanism unit by sending a camera angle setting signal 112 to each camera, and sets the desired camera angle.

  As another example, the camera angles of a plurality of cameras connected to the image encoding device 100 can be set by remote control from the image decoding device 114. The video signals of the cameras 1 to N (107, 108 to 109) sent from the image encoding device 100 via the network 116 are displayed on the monitor 2, and the input I / O of the image decoding device 114 is viewed while watching the video. By operating F2 (801), the horizontal direction and the vertical direction of each camera are set. The camera angle setting information is sent to the transmission / reception unit 702 via the overall decoding control unit 701, and is sent to the image coding apparatus 100 via the network 116.

  The image encoding device 100 transmits the received camera angle setting information to the camera control unit 102 via the overall encoding control unit 101. Then, the camera control unit 102 sends a camera angle setting signal 112 to each camera, moves the angle adjustment mechanism unit, and adjusts it to a desired camera angle.

  The input I / F1 (800) of the image encoding device 100 and the input I / F2 (801) of the image decoding device 114 may be those of a physical mechanism such as a button or a stick, and are displayed as a GUI of a program. A software I / F may be used.

  When only one monitor is connected to the image encoding device 100 or the image decoding device 114, the setting is made while switching the camera image to be displayed. Alternatively, when a plurality of videos are displayed together, the camera angle should be set after clarifying that it is the operation target by temporarily enlarging the video of the target camera. Also good.

<Example of video display>
FIG. 9 is a diagram illustrating an example in which a plurality of camera images are displayed on a monitor in the image decoding apparatus. In the figure, an example is shown in which there are three cameras connected to the image encoding device 100 and one to three monitors connected to the image decoding device 114. Here, the first camera video is referred to as video 1, the second camera video is referred to as video 2, and the third camera video is referred to as video 3.

  FIG. 9A shows an example in which the camera video and the monitor are displayed in a one-to-one relationship. Video 1 is displayed on monitor 1 (900), video 2 is displayed on monitor 2 (901), and video 3 is displayed on monitor 3 (903).

  FIG. 9B is an example in which three camera images are displayed together on one monitor 1 (904). Video 1 is enlarged and displayed relatively larger than video 2 and video 3.

  FIG. 9C is an example in which camera images for three cameras are displayed separately on the monitor 1 (904) and the monitor 2 (901). Video 1 is displayed on monitor 1 (904), and video 2 and video 3 are aggregated and displayed on monitor 2 (901).

  The display example in the figure is an example. The present invention is not limited to the combination of the camera video and the monitor display shown in the example of the figure, and the camera video may be displayed in other combinations.

<Encoding procedure>
FIG. 10 is a flowchart for explaining the procedure of the encoding process in the image encoding device 100.

  After starting the image encoding device 100, the overall encoding control unit 101 first performs initialization and simultaneously acquires the number N of cameras connected to the image encoding device 100 (step 1000).

  Next, after the camera control unit 102 sets the shooting angle of the camera (N units) (step 1001), the overall encoding control unit 101 performs camera angle information (horizontal and vertical) of the final camera (N units). (Direction) is acquired (step 1002), and the imaging target part of the camera (N units) is specified from the camera angle information (step 1003).

  Next, the encoding unit 103 refers to the encoding parameter table based on the identified target portion, and acquires encoding parameters used for video encoding of the cameras (N units) (step 1004). The overall encoding control unit 101 performs communication connection between the transmission / reception unit 1 (106) and the image decoding device 114 (step 1005), and the transmission / reception unit 1 (106) is a camera connected to the image encoding device 100. The number N is transmitted to the image decoding apparatus 114 (step 1006).

  Subsequently, the encoding unit 103 executes encoding processing of the video of the camera (N units) to generate encoded data (step 1007), and the transmission / reception unit 1 (106) decodes the encoded data into an image. Transmit to the device 114 (1008).

  Finally, the overall encoding control unit 101 determines whether or not to end the encoding process (step 1009). When the encoding process ends, the communication with the image decoding apparatus 114 is disconnected (step 1010). ), The process of the image encoding device 100 is terminated. On the other hand, when the encoding process is continued, the process returns to step 1007.

<Decryption procedure>
FIG. 11 is a flowchart for explaining the decoding processing procedure of the image decoding apparatus 114.

  After starting the image decoding apparatus 114, the overall decoding control unit 701 first performs initialization (step 1100) and establishes communication connection with the image encoding apparatus 100 (step 1101). The transmission / reception unit 2 (702) receives information on the number N of cameras connected to the image encoding device 100 (step 1102). Further, the transmission / reception unit 2 (702) receives the encoded data from the image encoding device 100 (step 1103), and the decoding unit 700 uses the encoded parameters corresponding to the encoded data for each camera (N units). (Step 1104).

  Subsequently, the overall decoding control unit 701 controls the monitor connected to the image decoding device 114 to display the decoded video (step 1105).

  Further, the overall decoding control unit 701 determines whether or not the next encoded data has been received (step 1106), and if the encoded data has been received, returns the processing to processing step 1103, If there is no reception, the communication with the image encoding device 100 is disconnected and the processing of the image decoding device 114 is terminated (step 1107).

<System operation example>
FIG. 12 is a diagram showing an example of the operation of a system using the image encoding device 100 of the present invention, and shows a schematic configuration example of a telemedicine support system.

  The image coding apparatus 100 of the present invention is connected to a plurality (N) of cameras (107, 108 to 109) and a monitor 1 (110). Further, the image encoding device 100 is connected to the image decoding device 114 via the network 116. Further, the image decoding device 114 is connected to the monitor 2 (115).

  The image coding apparatus 100 captures an image obtained by photographing a specific part of a patient 1200 lying on the back of an examination table 1203 with a plurality of cameras connected to the image coding apparatus 100, and displays a video for each camera. The data is encoded and transmitted to the image decoding device 114. Here, the image encoding device 100 and the image decoding device 114 may be in a remote relationship. In addition, on the image coding apparatus 100 side, there are a patient 1200 and a doctor 1 (1201) who directly performs a medical action on the patient 1200. There is a doctor 2 (1202) on the image decoding apparatus 114 side, and the doctor 1 (1201) on the image encoding apparatus 100 side is related to medical practice while observing the video sent from the image encoding apparatus 100. Advice can be given.

<Summary>
In the embodiment of the present invention, the camera angle of a plurality of cameras directed to the imaging target (for example, each part of the patient lying on the examination table) is acquired to specify the imaging target for each camera, and corresponds to the imaging target. The corresponding encoding parameter is read from the encoding parameter table storing the encoding parameter, the encoding process is performed for each camera image, and the encoded data is output. In this way, since it is possible to acquire the encoding parameters used for the compression of the camera video without a complicated operation by a simple procedure, the encoding processing load is reduced, and the image encoding device The cost can be reduced.

  The encoding parameter is determined in accordance with the imaging target of each camera based on the feature of the image from each camera, and is the optimum parameter with the highest efficiency for encoding each image. This encoding parameter may be read from a table, or may be determined one by one according to the characteristics of each image to be encoded. In this way, since encoding is performed using the encoding parameter with the best encoding efficiency, the images of each camera are not encoded and transmitted, but the continuous images of each camera are encoded and transmitted as they are. As a result, network communication bandwidth can be reduced. In addition, it is possible to ensure the real-time property of an image having a sufficient amount of information.

  Examples of the encoding parameter include information on an encoding mode, a quantization parameter, a macroblock size, and a motion vector search range that are generated based on the characteristics of the image to be imaged and the imaged object is encoded. . For example, when coding an image with little motion, such as a patient during surgery, the motion vector search range can be narrowed compared to when there is normal motion, so that coding efficiency can be improved. .

  Also, if the encoding parameters are multiplexed with the encoded data and transmitted to the image decoding device, the image decoding device does not need to have an encoding parameter table, and the existing image decoding device can be used as it is. .

  Note that when the number of cameras connected to the image encoding device is larger than the number of monitors connected to the image decoding device, the decoding process of the decoded image for each shooting target is executed, and all the decoding is performed on the monitor. Allow images to be displayed. As a result, it is not necessary to match the number of monitors on the image decoding apparatus side with the number of cameras, and the cost of the entire system can be reduced.

  Further, each of the image encoding and decoding devices may be provided with an input unit for inputting angle settings with respect to the imaging targets of a plurality of cameras. Then, the angles of the plurality of cameras are adjusted based on the angle setting information input from each input unit. In this way, the shooting position of the camera can be adjusted also from the image decoding device side.

  DESCRIPTION OF SYMBOLS 100 ... Image coding apparatus, 101 ... Encoding whole control part, 102 ... Camera control part, 103 ... Encoding part, 104 ... Encoding control part, 105 ... Encoding parameter table, 106 ... Transmission / reception part 1, 107 ... Camera DESCRIPTION OF SYMBOLS 1,108 ... Camera 2, 109 ... Camera N, 110 ... Monitor 1, 111 ... Video signal, 112 ... Camera angle setting signal, 113 ... Camera angle acquisition signal, 114 ... Image decoding apparatus, 115 ... Monitor 2, 116 ... network

Claims (8)

An image encoding device that encodes and transmits images captured by a plurality of cameras,
A camera control unit for acquiring shooting target specifying information for specifying a target to be shot by each of the plurality of cameras from the respective cameras;
The plurality of codes corresponding to the shooting targets of the respective cameras are most efficient for specifying the shooting targets of the respective cameras based on the shooting target specifying information and encoding the images from the respective cameras. An encoding control unit for acquiring encoding parameters;
Using the plurality of encoding parameters, a continuous image of each imaging target sent from each camera is encoded, and encoded data for each imaging target is generated, and each encoded data is multiplexed. An encoding unit
A transceiver for outputting the multiplexed encoded data;
An image encoding device comprising: In claim 1,
Furthermore, an encoding parameter table for storing an optimal encoding parameter for each imaging object corresponding to the imaging object of each camera is provided,
The encoding control unit acquires an encoding parameter corresponding to the identified imaging target from the encoding parameter table. In claim 2,
The shooting target specifying information includes information on a setting angle with respect to a shooting target of each camera,
The camera control unit transmits a camera angle setting signal to each of the cameras based on an input instruction, and controls each of the cameras so that a desired shooting target can be shot. Encoding device. In claim 2,
The encoding parameter is generated based on the characteristics of the image to be imaged, and includes information on an encoding mode, a quantization parameter, a macroblock size, and a motion vector search range when the imaged object is encoded. An image encoding device characterized by the above. An image encoding device for encoding and transmitting an image of each part of the human body obtained by photographing a human body with a plurality of cameras,
A camera control unit for acquiring imaging part specifying information for specifying each part to be imaged by each of the plurality of cameras from the respective cameras;
An encoding parameter table storing an encoding parameter most efficient for encoding an image of the imaging part for each imaging part corresponding to the imaging part of each camera;
An encoding control unit that specifies the imaging region of each of the cameras based on the imaging region specifying information, and acquires a plurality of encoding parameters corresponding to each of the specified imaging region;
Using the plurality of encoding parameters, each of the imaging parts sent from the respective cameras is encoded continuously, and encoded data for each of the imaging parts is generated. An encoding unit that multiplexes together with encoding parameters to generate multiplexed data;
A transceiver for outputting the multiplexed data;
An image encoding device comprising: An image processing system comprising: an image encoding device that encodes and transmits images captured by a plurality of cameras; and an image decoding device that decodes transmitted encoded data and outputs the decoded data to a monitor. ,
The image encoding device includes:
A camera control unit for acquiring shooting target specifying information for specifying a target to be shot by each of the plurality of cameras from the respective cameras;
An encoding parameter table storing an encoding parameter that is most efficient for encoding the image to be imaged for each image capturing object corresponding to the image capturing object of each camera;
An encoding control unit that specifies the imaging target of each of the cameras based on the imaging target specifying information, and acquires a plurality of encoding parameters corresponding to the imaging target of each of the cameras from the encoding parameter table;
Using the plurality of encoding parameters, each continuous image of each imaging target sent from each of the cameras is encoded to generate encoded data for each imaging target, and each encoded data and the An encoding unit that multiplexes each encoding parameter corresponding to the imaging target and generates multiplexed data;
An encoding side transmission / reception unit for transmitting the multiplexed encoded data to the image decoding device,
The image decoding device includes:
A decoding side transceiver for receiving the multiplexed data;
A decoding unit that performs a decoding process on the encoded data for each shooting target included in the multiplexed data using the corresponding encoding parameter, and generates a decoded image for each shooting target;
An image processing system comprising: a decoding control unit that outputs a decoded image for each photographing target to a monitor. In claim 6,
When the number of cameras connected to the image encoding device is larger than the number of monitors connected to the image decoding device, the decoding control unit executes a scaling process of the decoded image for each shooting target An image processing system displaying all decoded images on the monitor. In claim 6,
Each of the image encoding and decoding devices further includes an input unit for inputting an angle setting with respect to the shooting target of the plurality of cameras,
The image processing system, wherein the camera control unit adjusts angles of the plurality of cameras based on the angle setting information from the input unit.

Images