JP7314545B2 - Communication node, communication program, communication method, distribution configuration management device, and information distribution system - Google Patents

Description

The present invention relates to a communication node, a communication program, a communication method, a distribution configuration management device, and an information distribution system, and can be applied, for example, to an information distribution system that distributes multimedia data including video information and audio information to a plurality of user terminals.

2. Description of the Related Art In recent years, due to the development of information communication technology, attention has been paid to a technology that allows people in remote places to communicate with each other as if they were in the same place and to perform joint work. For example, an information distribution device (such as a distribution server) distributes multimedia data, including multiple pieces of video information and audio information, to multiple locations and multiple users (user terminals), thereby realizing communication between multiple remote parties.

When multimedia data is distributed to a plurality of users, a distribution source (distribution server) holding multimedia data obtained from a video source such as a video camera or an audio source such as a microphone distributes the data to a user requesting the data by unicast communication using IP packets or the like.

In such unicast communication, when the number of users requesting the same data increases, the distribution server duplicates and distributes the same data by the number of unicast communication channels corresponding to the number of users, which wastes network bandwidth and cannot be distributed to a sufficient number of users. There is also a method of preventing waste of network bandwidth by using multicast communication instead of unicast communication to duplicate data at a router in the middle of the distribution route, but it is not commonly used because all routers on the route must support multicast communication.

As a countermeasure against such problems, a method called application level multicast is known. This is a method in which a user receiving a distribution acts as a relay node, and by redistributing to another user, multicasting to a large number of users is realized only by the user's application.

In such application-level multicast, how the distribution route is constructed greatly affects the distribution performance of the entire system.

For example, Patent Literature 1 discloses a method of switching a distribution tree for distribution using application-level multicast according to the situation by measuring the throughput of a distribution path.

Japanese Patent Application Laid-Open No. 2007-235681

Here, an application such as a video dialogue or a video conference by a plurality of users is assumed by distributing each other's video information by using the application level multicast as described above. In such an application, a plurality of videos distributed from each user are laid out and displayed on the display screen of the user terminal, for example, by dividing the screen (eg, FIG. 6A). Also, it is conceivable that a certain user pays attention to a specific delivered video and displays it with a higher display resolution than other delivered videos (for example, FIG. 6(B)).

Assuming such a use, conventional application-level multicast technology has the problem of distributing the entire distribution video in high resolution to all users. For example, even if the distribution video is scaled down to a small display resolution on all user terminals participating in the distribution tree, the distribution video is distributed in the high resolution, which wastes the network bandwidth.

Therefore, a communication node, a communication program, a communication method, a distribution configuration management device, and an information distribution system capable of reducing the amount of information of video data to be distributed and reducing waste of network bandwidth while considering the display resolution required by each communication node are desired.

According to a first aspect of the present invention, in a communication node of a distribution source that multicasts video data on a tree-structured distribution route, (1) a resolution information receiving unit that receives resolution information including display resolution information of one or more lower communication nodes positioned below the distribution route, (2) a resolution information management unit that manages the resolution information including the display resolution information of each of the lower communication nodes received by the resolution information receiving unit, and (3) the resolution information including the display resolution information of each of the lower communication nodes managed by the resolution information management unit. (4) a resolution control unit that controls the resolution of video data to be distributed;, according to said distribution path already configuredand a transmitting unit for transmitting.

In a second aspect of the present invention, in a communication node that multicasts video data along a tree-structured distribution route, (1) a resolution information receiving section that receives resolution information including display resolution information of one or more lower communication nodes positioned below the distribution route, (2) a resolution information management section that manages the resolution information including the display resolution information of each of the lower communication nodes received by the resolution information receiving section and the display resolution information of its own device, and (3) the display resolution of each of the lower communication nodes managed by the resolution information management section. resolution information including information and resolution information including display resolution information of its own deviceintegrated information,A higher communication node positioned higher on the distribution routeFor resolution control in the upper communication node(4) a receiving unit for receiving video data from the upper communication node; (5) a display processing unit for outputting the received video data based on the display resolution information of the own device; (6) a resolution control unit for performing resolution control of the video data based on the resolution information including the display resolution information of each of the lower communication nodes managed by the resolution information managing unit; characterized by

According to a third aspect of the present invention, in a communication node that multicasts video data on a tree-structured distribution route, (1) a resolution information receiving section for receiving resolution information including display resolution information of one or more lower communication nodes positioned below the distribution route, (2) a resolution information management section for managing the resolution information including the display resolution information of each of the lower communication nodes received by the resolution information receiving section and the display resolution information of its own device, and (3) the display resolution of each of the lower communication nodes managed by the resolution information management section. resolution information including information and resolution information including display resolution information of its own deviceintegrated information,A higher communication node positioned higher on the distribution routeFor resolution control in the upper communication node(4) a receiving unit for receiving video data from the upper communication node; (5) a display processing unit for outputting video data based on the display resolution information of its own device; and (6) a retransmitting unit for resending the received video data.

A fourth aspect of the present invention is a distribution configuration management apparatus for managing a distribution tree configuration of a plurality of communication nodes constructed in a tree-like network with a communication node serving as a distribution source of video data as the apex, comprising a communication path setting unit that determines the distribution tree and instructs each of the communication nodes to set a communication path for a distribution path between the nodes constituting the distribution tree and to set a communication path for transmission and reception of resolution information between the nodes, and the resolution information is used for resolution control at a higher-level communication node positioned higher on the distribution path for each of the communication nodes. characterized by being used.

According to a fifth aspect of the present invention, there is provided a distribution configuration management apparatus for managing a configuration of a distribution tree of a plurality of communication nodes constructed in a tree-like network with a communication node serving as a distribution source of video data as an apex, comprising: (1) a communication path setting unit that determines the distribution tree and instructs each of the communication nodes to set a communication path for a distribution path between the nodes that constitute the distribution tree; and (2) a resolution information relay unit that relays transmission and reception of resolution information between the nodes.and (3) the resolution information is used for resolution control in a higher-level communication node positioned higher on the distribution route for each of the communication nodes.It is characterized by

A sixth aspect of the present invention provides an information delivery system comprising: a delivery source node that is a delivery source of video data; a plurality of communication nodes constructed in a tree-like network with the delivery source node at the top; and a delivery configuration management device that manages the configuration of the delivery tree, (1) the delivery configuration management device of the fifth aspect of the present invention is applied as the delivery configuration management device; (2-3) a receiving unit for receiving video data from a higher-level communication node positioned above a tree-structured distribution route, (2-4) a display processing unit for outputting received video data based on the display resolution information of its own device, and (2-5) a retransmitting unit for resending the received video data.

A seventh aspect of the present invention provides an information delivery system comprising: a delivery source node as a delivery source of video data; a plurality of communication nodes constructed in a tree-like network with the delivery source node at the top; and a delivery configuration management device for managing the configuration of the delivery tree, wherein: (1) the delivery configuration management device is the delivery configuration management device of the fourth aspect of the present invention; (2) the delivery source node is the communication node of the first aspect of the present invention; characterized by being

A communication program according to an eighth aspect of the present invention provides a computer installed in a communication node of a distribution source that multicasts video data on a tree-structured distribution route, (1) a resolution information receiving unit for receiving resolution information including display resolution information of one or more lower communication nodes positioned below the distribution route, (2) a resolution information management unit for managing the resolution information including the display resolution information of each of the lower communication nodes received by the resolution information receiving unit, and (3) a display of each of the lower communication nodes managed by the resolution information management unit. (4) a resolution control unit that controls the resolution of video data to be distributed based on resolution information including resolution information;, according to said distribution path already configuredIt is characterized by functioning as a transmission unit for transmission.

A communication program according to a ninth aspect of the present invention provides a computer installed in a communication node that multicasts video data on a tree-structured distribution route, (1) a resolution information receiving unit for receiving resolution information including display resolution information of one or more lower communication nodes positioned below the distribution route, (2) a resolution information management unit for managing resolution information including the display resolution information of each of the lower communication nodes received by the resolution information receiving unit, and the display resolution information of its own device, and (3) the resolution information management unit. Resolution information including display resolution information of each lower communication node and resolution information including display resolution information of its own deviceIntegrated integrated information,A higher communication node positioned higher on the distribution routeFor resolution control in the upper communication node(4) a receiving unit for receiving video data from the upper communication node; (5) a display processing unit for outputting the received video data based on the display resolution information of its own device; (6) a resolution control unit for controlling the resolution of the video data based on the resolution information including the display resolution information of each of the lower communication nodes managed by the resolution information managing unit; characterized by

According to a tenth aspect of the present invention, there is provided a communication method used by a communication node of a distribution source for multicast distribution of video data on a tree-structured distribution route, comprising: a resolution information receiving unit, a resolution information managing unit, a resolution control unit, and a transmitting unit; (3) the resolution control unit controls the resolution of video data to be distributed based on the resolution information including the display resolution information of each lower communication node managed by the resolution information management unit; (4) the transmission unit transmits the video data whose resolution is controlled by the resolution control unit, according to said distribution path already configuredIt is characterized by transmitting.

第１１の本発明は、ツリー構成の配信経路で映像データをマルチキャスト配信する通信ノードに使用する通信方法おいて、解像度情報受信部、解像度情報管理部、解像度情報送信部、受信部、表示処理部、解像度制御部、及び再送信部を備え、（１）前記解像度情報受信部は、前記配信経路の下位に位置する１又は２以上の下位通信ノードの表示解像度情報を含む解像度情報を受信し、（２）前記解像度情報管理部は、前記解像度情報受信部により受信された前記各下位通信ノードの表示解像度情報を含む解像度情報と、自装置の表示解像度情報とを管理し、（３）前記解像度情報送信部は、前記解像度情報管理部で管理されている前記各下位通信ノードの表示解像度情報を含む解像度情報と、自装置の表示解像度情報を含む解像度情報とを統合した統合情報を、前記配信経路の上位に位置する上位通信ノードでの解像度制御のために、該上位通信ノードに送信し、
(4) The receiving unit receives the video data from the above -mentioned communication node, (5) the displayed processing unit outputs the received video data based on the display resolution information of the device, and (6) the resolution control unit, which is managed by the resolution information management department, is managed by the resolution information of each of the low -level communication nodes. The resolution of the video data is performed based on the degree of information, and (7) the resolution portion is characterized by transmitting a redelivery video data that has been resolution control by the resolution control unit.

According to the present invention, while considering the display resolution required by each communication node, it is possible to reduce the amount of information of the video data to be distributed, thereby reducing waste of network bandwidth.

4 is a block diagram showing a functional configuration of a distribution source node according to the embodiment; FIG. 1 is an overall configuration diagram showing the overall configuration of an information delivery system according to an embodiment; FIG. 4 is a block diagram showing the functional configuration of a receiving node according to the embodiment; FIG. FIG. 4 is an explanatory diagram showing an image of display resolution of a receiving node according to the embodiment; FIG. 4 is an explanatory diagram showing an image of transmitting resolution information from a receiving node to a distribution node according to the embodiment; FIG. 10 is an explanatory diagram showing a display example of a distribution video in a conventional receiving node;

(A) Main Embodiments Hereinafter, embodiments of a communication node, a communication program, a communication method, a distribution configuration management device, and an information distribution system according to the present invention will be described in detail with reference to the drawings.

(A-1) Configuration of Embodiment (A-1-1) Overall Configuration FIG. 2 is an overall configuration diagram showing the overall configuration of the information distribution system according to the embodiment.

2, the information delivery system 1 according to this embodiment has a video delivery management server 10, a delivery source node 20, and a plurality of receiving nodes 30 (30-1 to 30-5). In the following description, the processing and configuration common to the receiving nodes will be described as receiving node 30 . Although five receiving nodes 30 are shown in FIG. 2, the number of receiving nodes 30 is not limited to this.

The distribution source node 20 distributes video information such as content data of video (which may include audio) and video data from a video source such as a video camera (which may include audio data from an audio source such as a microphone) according to the resolution requested by one or more receiving nodes 30. A distribution source node 20 transmits video information subjected to resolution control processing corresponding to resolution information notified from the receiving node 30 to each receiving node 30 as a direct distribution destination among a plurality of receiving nodes 30 in accordance with an instruction from the video distribution management server 10.例文帳に追加

The receiving node 30 receives information from the distribution source node 20 or other receiving nodes 30 via various networks (whether wired or wireless) typified by a WAN (Wide Area Network), a wide area LAN (Local Area Network), etc., and outputs and displays a video image of the distributed information at a desired resolution. Further, the receiving node 30 redistributes the received video information to the other receiving node 30 (hereinafter also referred to as "child node") of which the receiving node 30 is the parent in accordance with the instruction of the video distribution management server 10. The received video information is subjected to resolution control processing according to the resolution information notified from the other receiving node 30. Note that the receiving node 30 (or the delivery source node 20), which is the parent of the child node, is called a "parent node".

A video distribution management server 10 manages the configuration of a distribution tree between a distribution source node 20 and each reception node 30, and instructs the distribution tree configuration to the distribution source node 20 and the reception node 30 when a new reception node 30 joins or when the distribution tree is reconfigured due to the withdrawal of the reception node 30. Further, as will be described later, the video distribution management server 10 may transmit and receive resolution information directly between the receiving node 30 and the distribution source node 20, but the video distribution management server 10 may be configured to mediate transmission and reception of resolution information.

In addition, in the information distribution system 1, a plurality of distribution source nodes 20 may exist. In this case, the video distribution management server 10 manages a distribution tree for each distribution source (for each video content to be distributed). For example, the information distribution system 1 may be configured to implement communication by arranging the distribution source node 20 at each of a plurality of bases and bidirectionally distributing information among the plurality of bases.

(A-1-2) Configuration of Distribution Source Node 20 FIG. 1 is a block diagram showing the functional configuration of the distribution source node according to the embodiment. The distribution source node of the embodiment may be configured as hardware such as a dedicated IC chip on which each component shown in FIG. 1 is mounted, or may be configured as software centering on a CPU and a program executed by the CPU, but functionally it can be represented in FIG.

The distribution source node 20 has a resolution control section 203 , a transmission section 204 , a resolution information reception section 205 and a resolution information management section 206 .

The resolution control unit 203 inputs distribution data including video to be distributed, and controls the resolution of video for distribution to child nodes (receiving nodes 30 ) that directly receive distribution from the distribution source node 20 . The resolution of the video is controlled so that the resolution of the video is in accordance with the resolution information including the display resolution information of child nodes and their descendant nodes held in the resolution information management unit 206, which will be described later.

The transmission unit 204 distributes the resolution-controlled video to child nodes.

The resolution information receiving unit 205 receives resolution information from child nodes including display resolution information of child nodes and their descendant nodes (receiving nodes 30 forming a tree below child nodes on the distribution tree).

The resolution information management section 206 manages the resolution information received by the resolution information reception section 205 .

(A-1-3) Configuration of Receiving Node 30 FIG. 3 is a block diagram showing the functional configuration of the receiving node according to the embodiment. The receiving node of the embodiment may be configured as hardware such as a dedicated IC chip on which each component shown in FIG. 3 is mounted, or may be configured as software centering on a CPU and a program executed by the CPU, but functionally it can be represented in FIG.

The receiving unit 301 receives distribution data from a parent node (the distribution source node 20 or another receiving node 30).

The display processing unit 302 outputs and displays the received video at a resolution according to the display resolution information at the receiving node 30 instructed by the user.

The resolution control unit 303 controls the resolution of video for distribution to a child node when the receiving node 30 is a relay node that redelivers to a child node (another receiving node 30). The control of the video resolution controls the resolution of the video for redistribution according to the resolution information held in the resolution information management unit 306 described later.

Note that the receiving node 30 may be configured to omit the resolution control unit 303 and retransmit the received video with the same resolution without controlling the resolution. Further, as will be described later, in a configuration in which the video distribution management server 10 mediates resolution information exchanged between nodes, and in a configuration in which the resolution control unit 303 is omitted, the receiving node 30 may also be configured to omit the resolution information receiving unit 305 described later.

The retransmitting unit 304 distributes video for redistribution to child nodes.

The resolution information receiving unit 305 receives resolution information from child nodes including display resolution information of child nodes and their descendant nodes (receiving nodes 30 forming a tree below child nodes on the distribution tree).

The resolution information management section 306 manages the display resolution information of the reception node 30 itself and the resolution information from the resolution information reception section 305 as instructed by the user.

The resolution information transmission unit 307 transmits the resolution information obtained from the display resolution information of the receiving node 30 itself and the display resolution information of descendant nodes from the resolution information held in the resolution information management unit 306 as resolution information to the parent node.

(A-2) Operation of Embodiment Next, the operation of processing in the information distribution system 1 according to this embodiment will be described with reference to the drawings.

(A-2-1) Overall Operation (Information Distribution System 1) As shown in FIG. 2, a distribution source node 20, which is the distribution source of video information to be distributed, distributes information to receiving nodes 30 (30-1 to 30-5), which are receivers of the video information, using application level multicast.

A configuration state of a distribution tree serving as a distribution route of video information is managed by a video distribution management server 10, and node information on each node and information on the structure of the distribution tree are exchanged between a distribution source node 20 and a receiving node 30, thereby reconstructing the distribution tree according to dynamic addition or withdrawal of a node.

Any method can be used for the specific content of information related to the configuration of the distribution tree and the signaling for setting the communication path to be a specific distribution path. Further, the configuration may be such that the video distribution management server 10 also serves as a signaling server for setting a communication path for transmitting and receiving resolution information between the receiving node 30 and the distribution source node 20, or the role of relaying the transmission and reception of resolution information between nodes without directly transmitting and receiving resolution information between nodes.

First, the distribution source node 20 inputs distribution data, which is video to be distributed, and notifies the video distribution management server 10 of node information as the distribution source node.

The receiving node 30 notifies the video distribution management server 10 of node information as a receiving node including, for example, information specifying video data to be distributed.

A video distribution management server 10 determines the configuration of a distribution tree composed of a distribution source node 20 and one or more receiving nodes 30, and notifies each node (distribution source node 20 and receiving node 30) of information related to a connection partner of a distribution path.

Each node sets a communication path with a parent node for receiving distribution data and a communication path with a child node for transmitting distribution data, and transmits and receives distribution data.

Each node of the distribution source node 20 and the reception node 30 secures a communication path with the connection partner according to the distribution path, the distribution source node 20 transmits the video data controlled to the resolution according to the resolution information requested by one or two or more reception nodes 30, and the reception node 30 receives the distribution data from the parent node, and if the reception node 30 itself has a child node, the received video data is controlled to the resolution according to the resolution information requested by the reception node 30 that is a child node or a descendant node. Alternatively, the video data is retransmitted with the same resolution.

When a new receiving node 30 participates in the distribution tree, the video distribution management server 10 allocates a parent node (distributor node 20 or a receiving node 30 already receiving distribution) as a distribution source according to node information notified from the new receiving node 30, and the allocated parent node starts distribution to the new receiving node 30, thereby constructing a distribution tree.

On the other hand, when one of the receiving nodes 30 participating in the distribution tree withdraws from the distribution tree, distribution to the receiving node 30 having the withdrawn node as a parent node (or ancestor node) is stopped, so the video distribution management server 10 allocates a new parent node to the receiving node 30 whose distribution is stopped. The reassignment of the parent node may be performed only to the direct child node of the leaving node, or may be performed to the descendant nodes of the child node in addition to the direct child node. By reassigning parent nodes to these receiving nodes 30, the distribution tree is reconstructed.

(A-2-2) Characteristic Operation of Distribution Source Node 20 Distribution source node 20 receives distribution data, which is video to be distributed, but does not directly transmit the data, but performs resolution control processing according to resolution information notified from child nodes before transmission.

The video data, which is the input distribution data, uses the resolution control unit 203 of the distribution source node 20 to perform resolution control processing for distribution to child nodes (receiving nodes 30) that directly receive distribution from the distribution source node 20. Specifically, when the resolution of the input video data is higher than the resolution requested by the child node, the video is reduced. When the means for inputting delivery data is a camera device capable of inputting at a plurality of types of resolutions, or when video content is prepared at a plurality of types of resolutions in advance, the resolution control unit 203 selects and inputs the optimum input resolution. That is, select the smallest input resolution that is greater than the transmission resolution. If an input resolution higher than the transmission resolution cannot be selected, the maximum input resolution is selected and input, and the resolution control unit 203 supplies the image to the transmission unit 204 without enlarging it.

The video data obtained from the resolution control unit 203 is transmitted from the transmission unit 204 to each child node.

In addition, the distribution source node 20 receives resolution information from child nodes including display resolution information of child nodes and descendant nodes thereof (receiving nodes 30 forming a tree below the child nodes on the distribution tree) at the resolution information receiving unit 205 .

The resolution information received by the resolution information receiving section 205 is supplied to the resolution information managing section 206 . Then, the resolution control unit 203 performs processing for controlling the resolution of the video according to the resolution information including the display resolution information of the child nodes and their descendant nodes held by the resolution information management unit 206 .

(A-2-3) Characteristic Operation of Receiving Node 30 At the receiving node 30, display resolution information, which is information indicating the resolution desired to be displayed at each receiving node 30, is input. This is information such as the number of pixels (width, height) of the display area according to the layout on the screen, for example, when a plurality of images are displayed side by side as shown in FIG.

Receiving node 30 receives video data from a parent node (distributor node 20 or other receiving node 30), which is a direct distributor of video information, at receiving unit 301 . The received image data is output by the display processing unit 302 at a resolution according to the input display resolution information, and displayed on a layout portion such as a display.

When the receiving node 30 is a relay node that performs redistribution to a child node (another receiving node 30), the resolution control unit 303 controls the resolution of the video according to the resolution information including the display resolution information of the child node and the descendant node held in the resolution information management unit 306 for distribution to the child node, and the obtained video information is transmitted from the retransmitting unit 304 to each child node. However, if there is no child node, the receiving node 30 does not perform resolution control processing and retransmission processing.

Further, in the receiving node 30, the resolution control unit 303 may be omitted, and the video received by the receiving unit 301 may be retransmitted from the retransmitting unit 304 while maintaining the same resolution. The omission of the resolution control unit 303 may be mixed for each receiving node 30, or may be configured such that even within the same receiving node 30, processing may be dynamically omitted depending on the processing load or the like.

Receiving node 30 is also notified of resolution information from child nodes including display resolution information of receiving node 30 as a child node and receiving nodes as descendants thereof in the distribution tree, and receives resolution information receiving unit 305 .

The received resolution information from the child node and the display resolution information of the receiving node 30 itself are input to the resolution information management unit 306, and the resolution information management unit 306 supplies the resolution information necessary for the child node to the resolution control unit 303 according to this resolution information.

In addition, the resolution information management unit 306 supplies the resolution information obtained by integrating the resolution information from the child nodes and the display resolution information of its own to the resolution information transmission unit 307 for notification to the parent node, and the resolution information transmission unit 307 notifies the parent node. For integration of resolution information, for example, the maximum values of width and height are simply obtained and used as resolution information required for the node itself and descendant nodes.

(A-2-4) Details of Resolution Information Transmitted and Received Between Each Node (Receiving Node 30 and Distributor Node 20) FIG. 4 is an explanatory diagram showing an image of the display resolution of the receiving node according to the embodiment. Also, FIG. 5 is an explanatory diagram showing an image of transmitting resolution information including its own display resolution from a receiving node according to the embodiment to a distributing node.

As shown in FIG. 4, each receiving node 30 (receiving node 30-1 to receiving node 30-5), which is a user receiving video distribution from the distribution source node 20, is given a display resolution (display resolution 40-1 to display resolution 40-5) that is the resolution that the user wants to display. Resolution information is information such as the number of pixels (width and height) of the display area according to the layout on the user's screen.

Also, as shown in FIG. 5, each receiving node 30 integrates its own resolution information 50 with the resolution information 50 notified from the child node and notifies the resolution information 50 to the parent node. Integration of resolution information is obtained, for example, from the maximum values of width and height. These pieces of resolution information 50 are propagated to the parent node while the display resolutions of the receiving nodes 30 on the sequential path are integrated, and finally notified to the distribution source node 20 .

The transmission and reception of the resolution information 50 may be performed by providing a direct communication path between nodes (between the receiving node 30 and the distribution source node 20), or by relaying information via a server such as the video distribution management server 10. Further, for example, in the case of relaying by the video distribution management server 10, the resolution information transmission unit 307 may transmit only its own resolution information 50, and the video distribution management server 10 may integrate the resolution information 50 for each receiving node 30 according to the configuration state of the distribution tree, and then transmit to the resolution information receiving unit 305 and the resolution information receiving unit 205. In such a configuration, if the resolution control unit 303 is omitted from the receiving node 30, the resolution information 50 from the child node is not required, so the resolution information receiving unit 305 can also be omitted, and the video distribution management server 10 can also omit transmission of resolution information to such a receiving node 30.

Next, resolution control at each node (distribution source node 20 and reception node 30) will be described with reference to FIG.

As shown in FIG. 5, the child node notifies resolution information 50 that integrates the resolution information 50 of the child node and its descendant nodes (receiving nodes 30 forming the tree below the child node on the distribution tree). In other words, the resolution information 50 is notified so that the resolution is equal to or higher than the display resolution of all receiving nodes 30 below the child node.

In the resolution control unit 203 and the resolution control unit 303 in each node (distributor node 20 and receiving node 30), when the resolution of the input video or the received video is higher than the resolution required by the resolution information 50 from the child node, the video reduced to the required resolution is generated. If the requested resolution is larger, the resolution may be used as the transmission resolution without the need for enlargement control.

The case of omitting the resolution control unit 303 in the receiving node 30 is as described above. This reduces the processing load of the receiving node 30, although there are cases where the resolution is higher than necessary.

In the above description (example in FIG. 5), when there are a plurality of child nodes, resolution control processing is performed for each child node according to the resolution information of the distribution tree below the child node. However, for example, in order to reduce the processing load of the resolution control processing, the resolution control processing may be configured to generate only one type of video for transmission by integrating the resolution information 50 of all child nodes. That is, the transmission resolution is obtained based on the maximum value of the resolution information 50 from all child nodes, and only one type of video for transmission is generated. However, in this case, it is possible that video with a resolution higher than necessary is transmitted to child nodes and below.

Further, in the configuration where the video distribution management server 10 relays resolution information between nodes as described above, the video distribution management server 10 can grasp what display resolution each node constituting the distribution tree requests. The video distribution management server 10 can be configured, for example, to dynamically update the configuration of the arrangement tree in accordance with the network status of the distribution path notified from each node. At this time, the configuration of the distribution tree may also be updated in consideration of the resolution information requested by each node. That is, if a receiving node itself can be displayed at a low resolution and becomes the parent of a descendant node that requires a higher resolution image, it will be wasteful, so the structure of the distribution tree can be dynamically updated so as to reduce the number of such nodes.

Video information is distributed using the application level multicast by the above processing.

(A-3) Effects of Embodiment As described above, according to this embodiment, the following effects are obtained.

In the video information distribution system (information distribution system 1) using application-level multicast, the resolution control units (resolution control unit 203, resolution control unit 303) of the distribution source node 20 and the reception node 30, which constitute the distribution tree, can reduce the resolution of images for distribution according to the maximum resolution required by child nodes and their descendant nodes on the distribution tree. As for the video displayed by each receiving node 30, the video with the necessary resolution can be received, so that the information amount of transmission data and retransmission data transmitted to child nodes can be reduced without being adversely affected by the resolution control 203.例文帳に追加

That is, waste of network bandwidth can be reduced. In addition, as a result, there is a margin in the network band, so that it is possible to perform video encoding with higher image quality, and it is possible to reduce deterioration in image quality due to video encoding of video data output from each receiving node.

(B) Other Embodiments The present invention is not limited to the above-described embodiments, and modified embodiments as exemplified below can also be mentioned.

(B-1) In the above embodiment, an example of applying the present invention to an information distribution system that distributes video data, audio data, etc. was described, but the present invention is not limited to this, and can be applied to various information distribution systems (for example, a system that distributes various information such as documents and presentations).

(B-2) The present invention can be implemented as a system or device having the above configuration, or as a program that implements the processing of each device that constitutes the above system. For example, a downloadable program (for example, a Javascript program) that implements the functions of the distribution source node 20 and the reception node 30 can be placed on a server (web server or video distribution management server), and downloaded to a PC (downloaded to a web browser) to configure a server device (server program).

Reference Signs List 1 information delivery system 10 video delivery management server 20 delivery source node 30 receiving node 40 display resolution 50 resolution information 203 resolution control 203 resolution control unit 204 transmission unit 205 resolution information reception unit 206 resolution information management unit 301 reception unit 302 display processing unit 303 resolution control unit 304 retransmission unit 305 resolution information reception unit 30 6... Resolution information management unit, 307... Resolution information transmission unit.

Claims (16)

In a distribution source communication node that multicasts video data on a tree-structured distribution route,
a resolution information receiving unit that receives resolution information including display resolution information of one or more lower communication nodes positioned below the distribution path;
a resolution information management unit that manages resolution information including display resolution information of each of the lower communication nodes received by the resolution information reception unit;
a resolution control unit that controls the resolution of video data to be distributed based on resolution information including display resolution information of each lower communication node managed by the resolution information management unit;
A communication node, comprising: a transmission unit that transmits the video data whose resolution has been controlled by the resolution control unit, along the distribution route that has already been configured. In a communication node that multicasts video data on a tree-structured distribution route,
a resolution information receiving unit that receives resolution information including display resolution information of one or more lower communication nodes positioned below the distribution path;
a resolution information management unit that manages resolution information including display resolution information of each of the lower communication nodes received by the resolution information reception unit, and display resolution information of the device itself;
a resolution information transmission unit configured to transmit integrated information obtained by integrating resolution information including display resolution information of each of the lower communication nodes managed by the resolution information management unit and resolution information including display resolution information of the device itself to the upper communication node for resolution control at the upper communication node located above the distribution path;
a receiving unit that receives video data from the upper communication node;
a display processing unit that outputs the received video data based on the display resolution information of the device itself;
a resolution control unit that controls the resolution of video data based on resolution information including display resolution information of each lower communication node managed by the resolution information management unit;
A communication node, comprising: a retransmitting unit that transmits video data for redistribution whose resolution has been controlled by the resolution control unit. 3. The communication node according to claim 1 or 2, characterized in that, when the resolution of the video data is higher than the resolution required by the resolution information of the lower-level communication node that directly communicates, the resolution control unit performs resolution control so as to generate an image reduced to the required resolution. The resolution information management unit calculates a maximum display resolution from the resolution information including the display resolution information of each of the lower-level communication nodes managed and the display resolution information of the own device,
3. The communication node according to claim 2, wherein the resolution information transmission unit transmits the calculated maximum display resolution information to the upper communication node as the integrated information. In a communication node that multicasts video data on a tree-structured distribution route,
a resolution information receiving unit that receives resolution information including display resolution information of one or more lower communication nodes positioned below the distribution path;
a resolution information management unit that manages resolution information including display resolution information of each of the lower communication nodes received by the resolution information reception unit, and display resolution information of the device itself;
a resolution information transmission unit configured to transmit integrated information obtained by integrating resolution information including display resolution information of each of the lower communication nodes managed by the resolution information management unit and resolution information including display resolution information of the device itself to the upper communication node for resolution control at the upper communication node positioned above the distribution path;
a receiving unit that receives video data from the upper communication node;
a display processing unit that outputs video data based on the display resolution information of its own device;
A communication node, comprising: a retransmitting unit that retransmits received video data. A distribution configuration management device that manages the configuration of a distribution tree of a plurality of communication nodes constructed in a tree-like network with a communication node that is a distribution source of video data as the apex,
a communication path setting unit that determines the distribution tree and instructs each communication node to set a communication path for a distribution path between nodes constituting the distribution tree and to set a communication path for transmitting and receiving resolution information between nodes;
A distribution configuration management apparatus, wherein the resolution information is used for resolution control in a higher-level communication node positioned higher on a distribution route for each of the communication nodes. A distribution configuration management device that manages the configuration of a distribution tree of a plurality of communication nodes constructed in a tree-like network with a communication node that is a distribution source of video data as the apex,
a communication path setting unit that determines the distribution tree and instructs each of the communication nodes to set a communication path of a distribution path between the nodes that constitute the distribution tree;
a resolution information relay unit that relays transmission and reception of resolution information between the nodes;
A distribution configuration management apparatus, wherein the resolution information is used for resolution control in a higher-level communication node positioned higher on a distribution route for each of the communication nodes. a plurality of communication nodes as the delivery source;
the distribution tree has a plurality of tree-shaped networks with communication nodes of the distribution sources as vertices;
8. The distribution configuration management apparatus according to claim 6, wherein the communication path setting unit determines the configuration of each distribution tree according to distribution specifying information of video data requested by each communication node. An information distribution system comprising: a distribution source node that is a distribution source of video data; a plurality of communication nodes constructed in a tree-like network with the distribution source node as the top; and a distribution configuration management device that manages the structure of the distribution tree,
The delivery configuration management device according to claim 7 is applied as the delivery configuration management device,
The communication node is
a resolution information management unit that manages display resolution information of its own device;
a resolution information transmission unit that transmits resolution information including display resolution information of its own device to the distribution configuration management device;
a receiving unit that receives video data from a higher-level communication node positioned at a higher level in a tree-structured distribution route;
a display processing unit that outputs the received video data based on the display resolution information of the device itself;
An information distribution system, comprising: a retransmitting unit that retransmits received video data. 10. The information distribution system according to claim 9, wherein, when receiving the display resolution information from the communication node, the resolution information relay unit transmits integrated information obtained by integrating the received resolution information and the resolution information of a communication node located lower than the communication node that received the display resolution information to a higher-level communication node that is a direct video data distribution destination of the communication node that received the display resolution information. 11. The information distribution system according to claim 10 , wherein the resolution information relay unit calculates the maximum resolution from the received resolution information and the resolution information of communication nodes located lower than the communication node that received the display resolution information, and relays only the calculated maximum resolution information as the integrated information. An information distribution system comprising: a distribution source node that is a distribution source of video data; a plurality of communication nodes constructed in a tree-like network with the distribution source node as the top; and a distribution configuration management device that manages the structure of the distribution tree,
The delivery configuration management device according to claim 6 is applied as the delivery configuration management device,
The communication node according to claim 1 is applied as the delivery source node,
An information distribution system, wherein the communication node according to claim 2 is applied as the communication node. A computer installed in a communication node that is a delivery source that multicasts video data through a tree-structured delivery route,
a resolution information receiving unit that receives resolution information including display resolution information of one or more lower communication nodes positioned below the distribution path;
a resolution information management unit that manages resolution information including display resolution information of each of the lower communication nodes received by the resolution information reception unit;
a resolution control unit that controls the resolution of video data to be distributed based on resolution information including display resolution information of each lower communication node managed by the resolution information management unit;
A communication program characterized by functioning as a transmission section for transmitting video data whose resolution has been controlled by the resolution control section according to the already configured distribution route. A computer installed in a communication node that multicasts video data on a tree-structured distribution route,
a resolution information receiving unit that receives resolution information including display resolution information of one or more lower communication nodes positioned below the distribution path;
a resolution information management unit that manages resolution information including display resolution information of each of the lower communication nodes received by the resolution information reception unit, and display resolution information of the device itself;
a resolution information transmission unit configured to transmit integrated information obtained by integrating resolution information including display resolution information of each of the lower communication nodes managed by the resolution information management unit and resolution information including display resolution information of the device itself to the upper communication node for resolution control at the upper communication node located above the distribution path;
a receiving unit that receives video data from the upper communication node;
a display processing unit that outputs the received video data based on the display resolution information of the device itself;
a resolution control unit that controls the resolution of video data based on resolution information including display resolution information of each lower communication node managed by the resolution information management unit;
A communication program characterized by functioning as a retransmission unit that transmits video data for redistribution whose resolution has been controlled by the resolution control unit. In a communication method used for a communication node of a delivery source that multicasts video data through a tree-structured delivery route,
A resolution information receiving unit, a resolution information management unit, a resolution control unit, and a transmission unit,
The resolution information receiving unit receives resolution information including display resolution information of one or more lower-level communication nodes positioned below the distribution route,
The resolution information management unit manages resolution information including display resolution information of each of the lower communication nodes received by the resolution information reception unit,
The resolution control unit performs resolution control of video data to be distributed based on resolution information including display resolution information of each of the lower communication nodes managed by the resolution information management unit,
The communication method, wherein the transmission unit transmits the video data whose resolution has been controlled by the resolution control unit, according to the already configured distribution route. In a communication method used for a communication node that multicasts video data on a tree-structured distribution route,
A resolution information reception unit, a resolution information management unit, a resolution information transmission unit, a reception unit, a display processing unit, a resolution control unit, and a retransmission unit,
The resolution information receiving unit receives resolution information including display resolution information of one or more lower-level communication nodes positioned below the distribution route,
The resolution information management unit manages resolution information including display resolution information of each of the lower communication nodes received by the resolution information reception unit, and display resolution information of the device itself,
The resolution information transmission unit transmits integrated information obtained by integrating the resolution information including the display resolution information of each of the lower communication nodes managed by the resolution information management unit and the resolution information including the display resolution information of the own device to the upper communication node for resolution control in the upper communication node located higher in the distribution route;
The receiving unit receives video data from the upper communication node,
The display processing unit outputs the received video data based on display resolution information of its own device,
The resolution control unit performs resolution control of video data based on resolution information including display resolution information of each of the lower communication nodes managed by the resolution information management unit,
The communication method, wherein the retransmission unit transmits video data for redistribution whose resolution has been controlled by the resolution control unit.

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