JP2005086222A - Multicast type contents reception control method and multicast type contents reception client - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a real time method whereby a communication apparatus switches contents outputted on its client without causing a time difference. <P>SOLUTION: The method which a contents receiving client receiving a plurality of contents distributed via a network through a plurality of different multicast channels uses for receiving the contents includes the steps of: acquiring in advance a plurality of multicast channel information items corresponding to the plurality of contents; carrying out a reception procedure according to the multicast channel information items; receiving a request of switching the output contents on the contents reception client; and selecting concerned contents out of the plurality of contents having already been received and outputting the concerned contents. Thus, the client views the plurality of contents. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a multicast-type content reception control method and a multicast-type content reception client that perform switching and control of content output in a multicast-type content reception client when there are a plurality of contents to be distributed.

  Conventionally, in a multicast type content receiving client (hereinafter sometimes simply referred to as a client), when there are a plurality of contents distributed from a multicast type content distribution server, any content is output on the client, In addition, in order to switch the content output at an arbitrary timing, reception start processing and end processing for the distributed content are performed each time switching is performed. The reception start process and end process are performed as follows.

  A client desiring to receive multicast distribution content first makes a state in which information (packet) addressed to an IP multicast address corresponding to the content to be distributed can be received. Specifically, the receiving operation of the data addressed to the IP multicast address is started, and the process of opening the port having the port number corresponding to the IP multicast address is performed. Next, the client notifies the IP multicast address to the router corresponding to the multicast in the IP network to which the client is connected according to IGMP (Internet Group Management Protocol), and sends information (packet) addressed to the IP multicast address. A process of declaring reception (Join) is performed. By constructing a delivery path so that each router corresponding to multicast in the IP network by Join processing can transfer information (packet) addressed to the IP multicast address to the client that has performed Join processing, Information (packet) addressed to the IP multicast address reaches the client.

  Next, when the reception of the information (packet) addressed to the IP multicast address is terminated at the client, the client releases the state where the information (packet) addressed to the IP multicast address can be received. Specifically, the receiving operation of data addressed to the IP multicast address is terminated, and the process of closing the port having the port number corresponding to the IP multicast address is performed. Next, the client performs a process of declaring that the reception of information (packet) addressed to the IP multicast address is terminated according to IGMP to the router in the IP network to which the client is connected. Then, the information (packet) destined for the IP multicast address transferred by each router in the IP network by the Leave process does not reach the client.

  In the above method, the port open processing, join processing, close processing, and leave processing for starting and ending reception of the distributed content are performed mainly by the client (that is, the content receiving system side).

  On the other hand, as a method of switching content to be output on the client from among a plurality of content distributed from the multicast type content distribution server, there is a method of instructing reception start processing and end processing from the outside to the client (for example, Patent Document 1).

  In this method, a client that receives an arbitrary content (first content) is specified, and a communication device other than the client transmits the first content to the client via an IP network to which the client is connected. A request for switching to the second content is distributed.

  The client that has received the switching request determines whether to accept the request, and if accepting the request, ends the operation of receiving information (packets) addressed to the IP multicast address corresponding to the first content, and the IP Close the port number corresponding to the multicast address. Next, the client declares to the router in the IP network to which the client is connected that the reception of the information (packet) addressed to the IP multicast address is terminated according to IGMP (Leave), and each router in the IP network The information (packet) addressed to the IP multicast address to be transferred is not received.

  Then, in order to receive the information (packet) addressed to the IP multicast address corresponding to the second content requested to be switched from the communication device other than the client, the reception operation of the information (packet) addressed to the IP multicast address is started. Then, the port having the port number corresponding to the IP multicast address is opened. Next, the client declares that the router corresponding to the multicast in the IP network to which the client is connected receives information (packet) addressed to the IP multicast address according to IGMP. Then, each router corresponding to the multicast in the IP network constructs a delivery path so that information (packets) addressed to the IP multicast address is transferred to the client, and starts to transfer the information. (Packet) reaches the client.

  Through the series of operations described above, the content output on the client is switched from the first content to the second content by a communication device other than the client that receives the content.

  Also, in the IP network, the number of routers between the multicast type content distribution server and the client that receives the content is defined as the network diameter, and a set of IP multicast address and port number corresponding to one content is defined as a multicast channel. It is defined as

Normally, in a client that receives content distributed from a multicast type content distribution server, from reception processing that opens a port having a port number corresponding to the IP multicast address, until reception of information (packet) addressed to the IP multicast address starts The time required to complete increases as the diameter of the network increases. This is because the number of times control information is exchanged between each router, which is necessary for each router corresponding to multicast in the IP network to construct a delivery path for transferring information (packets) addressed to the IP multicast address to the client. This is because the route calculation amount on each router is proportional to the number of routers.
JP 2002-314600 A

  In the conventional method, there are a plurality of contents distributed from the multicast-type content distribution server, and in order to switch the contents to be output at the client that receives the contents, the IP multicast address corresponding to the output contents is switched every time the switching is performed. The above-described series of processing is performed.

  For this reason, in the conventional method, there is a problem that a time difference occurs in switching of the content to be output in the client that receives the content.

  Therefore, the present invention solves the problem that a time difference occurs when switching content to be output in a client that receives content distributed from a multicast type content distribution server. The client itself and a communication device other than the client However, it is an object of the present invention to provide a real-time method that does not cause a time difference when switching contents output on the client.

  In order to solve the above-described problems, in the present invention, a content receiving client that receives a plurality of contents distributed from one or a plurality of multicast-type content distribution servers through a plurality of different multicast channels via a network is the content receiving client. In the method of receiving content according to its own instruction, the content receiving client acquires a plurality of multicast channel information corresponding to the plurality of contents in advance, performs a reception procedure according to the multicast channel information, Receiving the request to switch the output content in the step, and the content receiving client selecting and outputting the corresponding content from the plurality of content already received. Those having a flop, which allows you to watch multiple content on the client.

  When a client and a communication device other than the client make a request to switch output contents on the client, the client selects and outputs corresponding contents from a plurality of contents already received. As a result, a plurality of contents can be viewed on the client.

  As described above, a multicast type content receiving client joins a plurality of multicast IP addresses according to IGMP to a router corresponding to the multicast in the IP network to which the multicast type content receiving client is connected, and receives a plurality of contents in advance. By making it possible, when there is a content switching request from the multicast type receiving client or a communication device other than the multicast type receiving client, it is possible to immediately switch the output content, which occurs in the conventional method. Thus, it is possible to prevent time consumption due to switching and the occurrence of harmful effects, and it is possible to view a plurality of contents without disturbance of images and sounds.

  A multicast-type content reception control method according to a first aspect of the present invention is a content reception client that receives a plurality of contents distributed from one or a plurality of multicast-type content distribution servers via a plurality of different multicast channels via a network. However, in the method of receiving content according to the instruction of the content receiving client itself, the content receiving client acquires a plurality of multicast channel information corresponding to the plurality of contents in advance, and performs a receiving procedure according to the multicast channel information; Receiving a request to switch output contents on the content receiving client, and the content receiving client switches from the plurality of contents already received. And a step of selecting and outputting content corresponding to the request, in a state in which a plurality of contents can be received in advance, or by receiving and accumulating the content other than the multicast type receiving client or the multicast type receiving client. When there is a content switching request from the communication device, it is possible to immediately switch the output content.

  The multicast type content reception control method according to the second aspect of the present invention is a content reception client that receives a plurality of contents distributed from one or a plurality of multicast type content distribution servers via a plurality of different multicast channels via a network. However, in the method for receiving content in accordance with an instruction from a communication device other than the content receiving client, the content receiving client acquires a plurality of multicast channel information corresponding to the plurality of contents in advance, and a reception procedure according to the multicast channel information. A step of receiving display content switching information from an external communication device, and a content receiving client switching the display content from a plurality of content already received. And a step of selecting and outputting content corresponding to the information. For example, the content is produced based on the intention of the producer or producer of the content, and the TV broadcast is performed by switching the content based on the intention. It can be enjoyed like a drama or sports broadcast.

  According to a third aspect of the present invention, in the multicast-type content reception control method according to the first aspect or the second aspect, the selection of content outputs any one or a plurality of contents. Thus, by selecting a plurality of contents to be multicast, it is possible to enjoy a plurality of contents with different appearances.

  According to a fourth aspect of the present invention, in the multicast-type content reception control method according to the second aspect, the step of receiving display content switching information from an external communication device receives a plurality of display content switching information. For example, it is possible to enjoy a plurality of contents produced based on the intentions of the creators and producers of the contents.

  A multicast type content receiving client according to a fifth aspect of the present invention is a content receiving client that receives a plurality of contents distributed from one or a plurality of multicast type content distribution servers via a plurality of different multicast channels via a network. A channel information receiving unit that acquires a plurality of multicast channel information corresponding to a plurality of contents in advance, a multicast information receiving unit that performs a receiving procedure according to the multicast channel information, and a request to switch output contents on the content receiving client A configuration having content switching control means and display content selection processing means for selecting and outputting content corresponding to the switching request from the plurality of contents already received In this case, by setting a state in which a plurality of contents can be received in advance, when there is a content switching request from a communication device other than the multicast receiving client or the multicast receiving client, the output content can be switched immediately. It becomes possible.

  According to a sixth aspect of the present invention, in the multicast type content receiving client according to the fifth aspect, the multicast content receiving client further includes content switching information distribution means for distributing the switching request as display content switching information. By distributing the display content switching information also from the client side, it is possible to enjoy content based on the intention of more people.

A multicast type content receiving client according to a seventh aspect of the present invention is a content receiving client that receives a plurality of contents distributed from one or a plurality of multicast type content distribution servers via a plurality of different multicast channels via a network. Channel information receiving means for acquiring a plurality of multicast channel information corresponding to a plurality of contents in advance, multicast information receiving means for performing a receiving procedure according to the multicast channel information, and a multicast channel for receiving display content switching information from an external communication device An information receiving unit; and display content selection processing means for selecting and outputting content corresponding to the display content switching information from the plurality of already received content Those that take the configuration, for example, are produced on the basis of the intention of the author and producer of content, it is possible to enjoy as drama and sports relay, which is TV broadcast by performing a switching of content based on the intention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
FIG. 1 is a block diagram of a multicast type content receiving client according to the first embodiment of the present invention.

  In FIG. 1, video input from a plurality of cameras (103-1 to 103-n) is received by the content input unit (104-1 to 104-n) and distributed to different multicast channels by the multicast transmission processing unit 105, respectively. Multicast type content distribution server 102, multicast type content reception client 112 that receives a plurality of contents distributed by multicast type content distribution server 102, and multicast channel information for a plurality of contents distributed from multicast type content distribution server 102 (for example, 4) on the multicast type content receiving client 112, and on the multicast type content receiving client 112. About the content to be displayed, and a display content switching information distribution device 106 that distributes a request to switch it to the multicast type content receiving client 112. The multicast type content distribution server 102, the multicast type content receiving client 112, the multicast channel information distribution device 101, and the display content switching information distribution device 106 are connected to the IP network 107.

  Specifically, videos from multiple viewpoints (for example, soccer games, movies, theater videos, etc. from multiple viewpoints) obtained by multiple shooting cameras installed at multiple points are set as different contents via the IP network. And a client (for example, multicast distribution video reproduction software operating on a PC) that receives the content (operated by a user who views the video). And according to his / her preferences, the user can display images displayed on the client (for example, images from the viewpoint of players who are interested in soccer game images, and images from actors who are interested in movies and stage images). ) Enjoy switching. Also, in response to an instruction request from the video production side (for example, program producer or movie director), control information for switching the video displayed on the client is distributed from a communication device other than the client, and the distributed video is effectively used by the user. It is also assumed that the viewers will watch.

  Next, the multicast type content distribution server 102 will be described.

  The multicast-type content distribution server 102 sends multi-viewpoint images captured by a plurality of cameras (103-1 to 103-n) installed at multiple points to the content input units (104-1 to 104-n). input. The content input units (104-1 to 104-n) convert each input video into a video signal format that can be played back by a client (for example, multicast distribution video playback software on a PC).

  The multicast transmission processing unit 105 divides the video signal from the content input unit (104-1 to 104-n) into packets, and sets the content as a plurality of different contents for each content input unit (104-1 to 104-n). Deliver to different multicast channels.

Next, the operation of the multicast type content receiving client 112 will be described using the operation flow of FIG.

  A multicast channel information receiving unit 113 of a multicast type content receiving client 112 (for example, a multicast type distribution video reproduction software operating on a PC) receives a plurality of pieces of multicast channel information on which a plurality of contents are distributed by the multicast type content distribution server 102. Acquired from the multicast channel information distribution apparatus 101 and stored in the multicast channel information storage unit 114 (S201). An example of the multicast channel information is shown in FIG. The multicast channel information 300 includes an IP multicast address 301, a port number 302, and a channel name 303.

  Next, the multicast information receiving unit 115 opens the port having the port number 302 corresponding to one or more IP multicast addresses 301 described in the multicast channel information 300 (S202).

  Further, the multicast information receiving unit 115 sends a plurality of IP multicast addresses described in the multicast channel information 300 according to IGMP to the router 108 corresponding to the multicast in the IP network 107 to which the multicast type content receiving client 112 is connected. Join to 301 (S203).

  Through these series of processes, the multicast content receiving client 112 causes the multicast information receiving unit 115 to send packets (110-1 to 110-n) addressed to a plurality of multicast channels distributed by the multicast content distribution server 102 via the IP network 107. In this state, reception is possible and reception is started (S204). The received packets (110-1 to 110-n) are accumulated in the received content accumulation unit 125 by the primary accumulation unit 116 for each multicast channel (S205). Note that the received content storage unit 125 is the primary storage and overwrites the old content when it is full.

  Next, the content switching operation in the multicast type content receiving client 112 will be described.

  In order to switch the content displayed on the display unit 123, the user inputs the request from the content switching input unit 120 (for example, a button for channel selection prepared in the video reproduction software), and the information is The content intended by the user is displayed on the display unit 123 by being transmitted from the content switching control unit 121 to the display content selection processing unit 124.

  Specifically, for example, as shown in FIG. 3, content types 304 and camera viewpoints 305 are described corresponding to each channel 303, and this information is displayed on the display unit 123 to allow the user to select. To do. Alternatively, the channels may be sequentially selected and the contents thereof may be displayed on the display unit 123. The history of switching by the user may be stored in the content switching information storage unit 117 as the display content switching information 111.

  Further, content different from the displayed content or the content being viewed may be stored in the display content storage unit 122 and not erased or overwritten unless instructed.

  In addition, the user can display the content accumulated in the received content accumulation unit 125 on the display unit 123 at a later date and repeatedly view the content.

  In addition, the user can switch the content displayed on the display unit 123 from the content stored in the received content storage unit 125 at a later date according to the switching history stored in the content switching information storage unit 117 and repeatedly watch the content. it can.

  Further, the multicast type content receiving client 112 receives the display content switching information 111 distributed from the external display content switching information distribution device 105 by the content switching information receiving unit 118, and the display content switching information 111 is received by the content switching control unit 121. To the content selection processing unit 124, the content according to the display content switching information 111 can be displayed on the display unit 123. In addition, the content switching control unit 121 stores the received display content switching information 111 in the content switching information storage unit 117.

  The display content switching information 111 distributed from the outside is produced based on the intention of the creator or producer of the content, for example, such as a TV broadcast drama or a sports broadcast by switching the content based on the intention. Can enjoy. In addition, a plurality of display content switching information 111 may be distributed by a plurality of producers having different viewpoints and may be selected by the user. As described above, by switching to a state in which a plurality of contents can be received in advance (because they are received and stored?), The contents are switched from the multicast receiving client or a communication device other than the multicast receiving client. When requested, it is possible to switch the output content immediately, and it is possible to prevent the time consumption caused by the switching that has occurred in the conventional method and the adverse effects caused by it, and without disturbing the image and sound. Content can be viewed.

  Note that a plurality of multicast type content distribution servers 102 can be configured.

  The multicast channel information distribution apparatus 101 and the multicast type content distribution server 102 can be realized on the same apparatus.

  The multicast channel information distribution apparatus 101 and the display content switching information distribution apparatus 106 can be realized on the same apparatus.

  The multicast content distribution server 102 and the display content switching information distribution device 106 can be realized on the same device.

  The multicast channel information distribution apparatus 101, the multicast content distribution server 102, and the display content switching information distribution apparatus 106 can be realized on the same apparatus.

  Note that the content displayed on the screen 123 can be recorded by the display content storage unit 122.

  The display content switching information 111 is distributed from the display content switching information distribution device 106 at the timing of switching the content, or distributed from the display content switching information distribution device 106 as a file in which all the content switching timing and the switching request are described. Is done.

As described above, a multicast type content receiving client joins a plurality of multicast IP addresses according to IGMP to a router corresponding to the multicast in the IP network to which the multicast type content receiving client is connected, and receives a plurality of contents in advance. By making it possible, when there is a content switching request from the multicast type receiving client or a communication device other than the multicast type receiving client, it is possible to immediately switch the output content, which occurs in the conventional method. Thus, it is possible to prevent time consumption due to switching and the occurrence of adverse effects, and it is possible to view a plurality of contents without disturbance of images and sounds.

(Embodiment 2)
FIG. 4 is a block diagram of a multicast type content distribution system according to the second embodiment of the present invention.

  The basic configuration of the second embodiment is the same as that of the first embodiment except that content switching information can be distributed from a multicast-type content receiving client. The difference will be mainly described.

  In FIG. 4, similarly to the first embodiment, a multicast type content distribution server 204 that distributes a plurality of contents to different multicast channels, and a multicast type content reception that receives a plurality of contents distributed by the multicast type content distribution server 204 Clients 207 and 218, and multicast channel information distribution apparatus 201 that distributes multicast channel information (for example, shown in FIG. 3) for a plurality of contents distributed from multicast type content distribution server 204 to multicast type content reception clients 207 and 218. . Also, the multicast type content distribution server 204, the multicast type content receiving clients 207 and 218, and the multicast channel information distribution device 201 are connected to the IP network 206.

  The multicast type content receiving clients 207 and 218 acquire the multicast channel information 202 and 203 from the multicast channel information distribution device 201 as in the first embodiment, and are distributed from the multicast type content distribution server 204 based thereon. It is assumed that a plurality of contents are received. The process is the same as that in the first embodiment until the port is opened, and a plurality of IP multicast addresses 301 described in the multicast channel information 300 are joined to start reception.

  Next, the user of the multicast type content receiving client 207 inputs the request from the content switching input unit 215 to switch the content displayed on the display unit 212, and the information is selected from the content switching control unit 214. By being transmitted to the processing unit 211, the content intended by the user or the producer is displayed on the display unit 212.

  Specifically, for example, as shown in FIG. 3, content types 304 and camera viewpoints 305 are described corresponding to each channel 303, and this information is displayed on the display unit 212 to be selected by the user. To do. The history switched by the user or the producer is temporarily stored in the content switching control unit 214, and the stored history is distributed as the display content switching information 217 from the content switching information distribution unit 213. The producer may perform creation / distribution of the display content switching information 217, and the display content switching information 217 may be distributed free of charge or paid to a user registered in advance.

  Note that the creation / distribution of the display content switching information 217 may be created when a plurality of producers create from each viewpoint or based on the intention of a plurality of producers.

  On the other hand, the multicast content receiving client 218 receives the content switching information 217 by the content switching information receiving unit 219 via the IP network 206.

  The content switching information 217 is transmitted from the content switching information receiving unit 219 to the display content selection processing unit 223 via the content switching control unit 220. The display content selection processing unit 223 selects the display content based on the content switching information 217, so that the display unit 225 can view the same content as the display unit 212.

  As described above, in the present embodiment, for example, content (channel) to be viewed based on the intention of a certain user or producer is created as display content switching information 217 and distributed, so that the content recommended by the user or producer is viewed. It becomes possible.

  The multicast channel information distribution apparatus 201 and the multicast type content distribution server 204 can be realized on the same apparatus.

  As described above, the content switching information can be distributed from the multicast type content receiving client, and the content based on the intention of more people can be enjoyed by distributing the display content switching information also from the client side. be able to.

  In addition, the display content selection processing means for selecting and outputting content corresponding to the display content switching information from a plurality of content that has already been received, for example, based on the intention of the content creator or producer By switching the content based on the intention, it can be enjoyed like a TV drama or a sports broadcast.

  The present invention provides a multicast-type content reception control method that can immediately switch output contents when there is a content switching request, such as a technical field for viewing a plurality of contents without image or audio disturbance. Applicable to usage.

1 is a block configuration diagram of a multicast type content distribution system according to a first embodiment of the present invention. Flowchart for receiving a plurality of contents in a multicast type content receiving client according to the present invention The figure which shows the example of the multicast channel information which concerns on this invention The block block diagram of the multicast type content delivery system which concerns on the 2nd Embodiment of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Multicast channel information delivery apparatus 102 Multicast type | mold content delivery server 103-1, ..., 103-n Camera 104-1, ..., 104-n Content input part 105 Multicast transmission process part 106 Display content switching information Distribution device 107 IP network 108 Multicast-compatible router 109 Multicast channel information 110-1,..., 110-n Content 111 Display content switching information 112 Multicast type content receiving client 113 Multicast channel information receiving unit 114 Multicast channel information accumulating unit 115 Multicast information receiving unit 116 Temporary storage unit 117 Content switching information storage unit 118 Content switching information receiving unit 120 Content switching input Unit 121 content switching control unit 122 display content storage unit 123 display unit 124 display content selection processing unit 125 received content storage unit 201 multicast information distribution device 202 multicast channel information 203 multicast channel information 204 multicast type content distribution server 205-1,. 205-n Content 206 IP network 207 Multicast-type content receiving client 208 Multicast channel information receiving unit 209 Multicast information receiving unit 210 Temporary storage unit 211 Display content selection processing unit 212 Display unit 213 Content switching information distribution unit 214 Content switching control Unit 215 content switching input unit 217 content switching information 218 multicast type content reception Client 219 content switching information receiving unit 220 content switching control unit 221 multicast information receiving unit 222 temporarily stores part 223 display the content selection unit 224 multicast channel information reception section 225 display unit

Claims (7)

In a method in which a content receiving client that receives a plurality of contents distributed from one or a plurality of multicast-type content distribution servers via a network by using a plurality of different multicast channels receives the contents in accordance with the instructions of the content receiving client itself The content receiving client acquires a plurality of multicast channel information corresponding to the plurality of contents in advance, performs a reception procedure according to the multicast channel information, and receives a request to switch the output content on the content receiving client; And a content receiving client selecting and outputting a content corresponding to the switching request from a plurality of content already received. Door type content reception control method. A content receiving client that receives a plurality of contents distributed from one or a plurality of multicast type content distribution servers via a plurality of different multicast channels via a network in accordance with instructions from a communication device other than the content receiving client, In the receiving method, the content receiving client acquires in advance a plurality of multicast channel information corresponding to the plurality of contents, a step of performing a receiving procedure according to the multicast channel information, and a step of receiving display content switching information from an external communication device And a content receiving client selecting and outputting content corresponding to the display content switching information from a plurality of content that has already been received. Strike type content reception control method. 3. The multicast type content reception control method according to claim 1, wherein the content selection is performed by outputting any one or a plurality of contents. 3. The multicast content reception control method according to claim 2, wherein the step of receiving display content switching information from an external communication device receives a plurality of display content switching information. In a content receiving client that receives a plurality of contents distributed from one or a plurality of multicast-type content distribution servers via a plurality of different multicast channels via a network, a plurality of multicast channel information corresponding to the plurality of contents is acquired in advance. Channel information receiving means, multicast information receiving means for performing a receiving procedure according to the multicast channel information, content switching control means for receiving a request to switch output contents on the content receiving client, and the plurality of contents already received A multicast content receiving client comprising: a display content selection processing means for selecting and outputting content corresponding to the switching request. 6. The multicast content receiving client according to claim 5, further comprising content switching information distribution means for distributing the switching request as display content switching information. In a content receiving client that receives a plurality of contents distributed from one or a plurality of multicast-type content distribution servers via a plurality of different multicast channels via a network, a plurality of multicast channel information corresponding to the plurality of contents is acquired in advance. Channel information receiving means, multicast information receiving means for performing a receiving procedure according to the multicast channel information, a multicast channel information receiving section for receiving display content switching information from an external communication device, and a plurality of contents already received from the content A multicast type content receiving client comprising display content selection processing means for selecting and outputting content corresponding to display content switching information.

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