JP5532768B2 - Video distribution system, bandwidth limiting method thereof, management server, and program - Google Patents

Description

  The present invention relates to a moving image distribution system, a band limiting method thereof, a management server, and a program, and more particularly to a technique for preventing a user who uses a moving image distribution system from feeling uncomfortable with band limitation.

  Patent Document 1 is cited as a technique related to the present invention. In Patent Document 1, user access to a shared wideband signal can be used for each user based on the amount of signal bandwidth used for the purpose of evenly distributing access to the shared wideband signal with a specified bandwidth. Controlling the amount of signal bandwidth is described.

JP 2005-527995 Gazette

  In a general video distribution system (hereinafter referred to as “VOD system”), service providers predict peaks due to problems such as communication delays due to traffic concentration and increase, and frame dropping / cracking. Respond by augmenting the server. In the technical field related to data transmission, there are a best effort type response method and a guarantee type response method as methods for dealing with traffic concentration without increasing the number of servers.

  In the Internet world, network operators adopt the best effort type. In the best effort type, the bandwidth of the user is equally limited according to the increase or decrease of traffic, so the communication quality obtained by the user differs depending on the number of users and the bandwidth used at that time.

  The guarantee type that is paired with the best effort type secures a band for each individual user, whereas the best effort type shares one band among a plurality of users.

  In addition, in the case of mobile networks including mobile phones, certain bandwidth is set on the carrier side in order to prevent specific users from occupying the network and preventing other users from obtaining sufficient line quality. There are many contractors who limit the line bandwidth of users who use more than that and users who use more than a certain period of time.

  Some hotels have introduced a VOD system as a service for hotel guests. Conventional in-hotel VOD systems often adopt the best effort type, and the viewing quality tends to decrease as the number of users increases.

  It is conceivable to limit the bandwidth in order to suppress this degradation in quality, but if high bandwidth content or cumulative traffic, as implemented by carriers, was selected, high-quality content was selected. This will reduce the viewing quality of users and regular customers.

  In order to adopt the guarantee type, it is necessary to secure a communication band enough to allow stable video viewing in each guest room regardless of whether the service is used or not, which is problematic in terms of efficiency and cost.

  Needless to say, the problems as described above are not only problems in the VOD system in the hotel. For example, this is a problem common to VOD systems closed to a certain range, such as VOD systems in airplanes.

  In view of the above circumstances, the present invention takes into account the allowance for bandwidth limitation for each client, and does not make the user who uses the video distribution system feel uncomfortable with the bandwidth limitation, and its bandwidth limitation method An object is to provide a management server and a program.

  To achieve the above object, the present invention provides, as a first aspect, a moving image including a distribution server that distributes a moving image, a client that receives and reproduces the distributed moving image, and a management server that controls the distribution server. In the distribution system, the distribution server includes distribution control means for monitoring a state of a band used for moving image distribution and transmitting the state of the band to the management server, and the client stores the distributed moving image. Storing means for reproducing, reproducing means for reproducing the accumulated moving picture, transmitting means for transmitting the difference between the data amount of the moving picture accumulated by the accumulating means and the data amount of the moving picture reproduced by the reproducing means, to the management server; The management server, in order from the client with the largest difference in the amount of data received from the client, gives a lower priority, and received from the distribution server A distribution management means for determining whether or not to perform bandwidth limitation based on a state of the region, and determining that the bandwidth to be used for moving image distribution to the low priority client is limited when it is determined to perform the bandwidth limitation; The distribution control means of the distribution server provides a moving picture distribution system, wherein the band is limited based on the determination of the distribution management means.

  In order to achieve the above object, the present invention provides, as a second aspect, a distribution server that distributes a moving image, a client that receives and reproduces the distributed moving image, a management server that controls the distribution server, A bandwidth limiting method in a video distribution system including: monitoring a state of a band used for video distribution by the distribution server, transmitting the band state to the management server, and distributing the video by the client , The stored video is reproduced, the difference between the accumulated video data amount and the reproduced video data amount is transmitted to the management server, and the management server receives the difference in the data amount received from the client. In order from the largest client, a lower priority is assigned, and based on the state of the bandwidth received from the distribution server, it is determined whether or not to perform bandwidth limitation. In this case, it is determined to limit the bandwidth used for moving image distribution to the low priority client, and the distribution server determines to limit the bandwidth used for moving image distribution to the low priority client. The present invention provides a method for limiting the bandwidth of a moving image distribution system, wherein the bandwidth is limited based on the above.

  In order to achieve the above object, according to the present invention, as a third aspect, for each client, data management means for managing the difference between the data amount of the moving image accumulated by the client and the data amount of the reproduced moving image, In order from the client with the largest difference in data amount, a lower priority is assigned, and it is determined whether or not to limit the bandwidth based on the state of the bandwidth used for moving image distribution. And a distribution management means for determining whether to limit a bandwidth used for moving image distribution to a low-cost client.

  In order to achieve the above object, according to a fourth aspect of the present invention, as a fourth aspect, the computer manages, for each client, a data management for managing a difference between a moving image data amount accumulated by the client and a reproduced moving image data amount. In the order from the client and the client with the largest difference in data amount, assign a low priority, determine whether or not to perform bandwidth limitation based on the state of the bandwidth used for video distribution, The present invention provides a program that functions as a distribution management means for determining whether to limit a bandwidth used for moving image distribution to a client having a low priority.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the moving image delivery system which does not make the user who uses a moving image delivery system feel the discomfort accompanying a bandwidth restriction | limiting, the bandwidth limiting method, a management server, and a program.

It is a figure which shows the example of the whole system configuration | structure of the form for implementing this invention. It is a block diagram which shows the function structure of the principal part of FIG. It is a timing chart figure which shows the process sequence of each functional block of FIG. It is a conceptual diagram for demonstrating the criterion of the zone | band limitation object terminal in the form for implementing this invention.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. In addition, although this embodiment has shown the example which applied this invention to the VOD system which distributes a moving image to the hotel guest, of course, this is an example for description, Comprising: The technical idea is not limited to hotels.

  FIG. 1 is a diagram showing an example of the overall system configuration of the present embodiment. The present embodiment is applied to a network system limited to a predetermined range such as a hotel. As shown in FIG. 1, the overall system of the present embodiment is a system in which a server in a management room and a client in a guest room are communicably connected via a network. In the management room, the VOD server 100 and the management server 300 are connected via a hub 400. In the guest room, the guest room terminal 200 in each guest room is connected to the hub 400.

  In FIG. 1, it is described that the VOD server 100 is physically installed in the management room. However, for example, in a network system limited to a predetermined range such as a data center of a service provider. It may be installed in a physically separated place.

  FIG. 2 shows a functional configuration of the main part of the present embodiment. As illustrated in FIG. 2, the VOD server 100 includes video data, a video management unit 101, a distribution control unit 102, and a transmission unit 103, and the management server 300 includes a reception unit 301 and a data management unit 302. And a distribution management unit 303. On the other hand, the guest room terminal 200 includes a reception unit 201, a storage unit 202, a playback unit 203, a display unit 204, a measurement unit 205, an input unit 206, a request unit 207, and a transmission unit 208. In the following, functions and cooperative relationships provided in each unit will be described.

  In FIG. 2, the distribution control unit 102 has a function of monitoring the status of the network and bandwidth used for moving image distribution, a function of transmitting the monitored bandwidth status to the management server 300, and a function of executing bandwidth limitation. Is provided.

  In FIG. 2, when content distribution is requested from the request unit 207 of the guest room terminal 200, the content distribution request is received by the management server 300, and the distribution management unit 303 instructs the distribution control unit 102 of the VOD server 100 to distribute. Thus, the requested video data is distributed to the guest room terminal 200.

  When receiving the data distribution, in the guest room terminal 200, the video data received by the receiving unit 201 is buffered by the storage unit 202, reproduced by the reproducing unit 203, and displayed on the display unit 204. At this time, the storage unit 202 and the reproduction unit 203 manage the buffer size and the reproduced data size so that they can be answered in response to a request from the measurement unit 205, and the measurement unit 205 periodically stores the storage unit 202 and the reproduction unit 203. The data size is acquired from the data, and the difference between the two data and the buffer size are transmitted from the transmission unit 208 to the management server 300. The management server 300 receives the information transmitted from the cabin terminal 200 by the receiving unit 301.

  In the management server 300, the data received from each guest room terminal 200 is managed by the data management unit 302 for each guest room terminal 200, and the received data is updated until the end of distribution. The distribution management unit 303 monitors the necessity of bandwidth limitation from the total size of bandwidths used for all video distributions managed by the distribution control unit 102 of the VOD server 100, and when bandwidth limitation is necessary. Referring to the data received from each guest room terminal 200 managed by the data management unit 302, the upper limit size of the use band is corrected downward from the distribution with the highest allowance for the band limitation, and according to the insufficient band By changing the number of bandwidth-limited communications, the viewing quality of the entire service is ensured.

  Here, in the present embodiment, “tolerance to bandwidth limitation” is measured by assigning distribution priority to each client in the distribution management unit 303 of the management server 300. The criteria for determining the bandwidth restriction target terminal based on the distribution priority will be described later with reference to FIG.

  Also, the distribution control unit 102 changes the upper limit of the band allocated to the distribution upward even when the tolerance to the band limitation is below a certain standard among the data managed by the data management unit 302. Prevent deterioration. In addition, when it is likely that it is difficult to ensure viewing quality even if band limitation is performed, a process of rejecting a new distribution request from the guest room terminal 200 is also performed.

  Next, with reference to the timing chart of FIG. 3, the procedure of processing executed by each unit shown in FIG. 2 will be further described. As shown in FIG. 3, the distribution control unit 102 monitors the state of the network and communication band used for moving image distribution (step S <b> 101), and manages the state of the monitored network and communication band (monitoring result). To the distribution management unit 303 (step S102). Steps S101 and S102 are performed as needed. The monitoring result transmission (step S102) may be performed only when there is an abnormality in the band state.

  When there is a moving image content distribution request from any one of the guest room terminals 200, the distribution management unit 303 receives the distribution request (step S103), and issues a distribution instruction to the distribution control unit 102 (step S104). The distribution control unit 102 distributes the video data to the guest room terminal 200 that has made the distribution request (step S104).

  The distributed video data is first buffered in the storage unit 202. The storage unit 202 outputs the buffered video data in response to the playback request from the playback unit 203 to the playback unit 203 (step S105). On the other hand, the storage unit 202 manages the buffer size of the stored video data so that it can respond in response to a request from the measurement unit 205. Similarly, the playback unit 203 manages the played back data size. The measurement unit 205 periodically acquires the data size from the storage unit 202 and the reproduction unit 203 (steps S106 and S107) and transmits the data size to the management server 300.

  The data management unit 302 of the management server 300 manages the data size received from each guest room terminal 200 for each guest room terminal 200 (steps S108 and S109). The information regarding the managed data size is used when the distribution management unit 303 determines the band limitation target.

  The distribution management unit 303 determines whether or not band limitation is necessary based on the band status monitored by the distribution control unit 102 (step S110). The determination in step S110 is performed as needed. When it is determined that the bandwidth limitation is necessary (step S110 / Yes), the distribution management unit 303 determines the bandwidth limitation target terminal based on the distribution priority described later (step S111). When the bandwidth limitation target terminal is determined, the distribution management unit 303 instructs the distribution control unit 102 to perform bandwidth limitation on the terminal (step S112). In response to this instruction, the distribution control unit 102 performs band limitation (step S113).

  Next, the criteria for determining the bandwidth restriction target terminal based on the distribution priority will be described with reference to FIG. FIG. 4 is a conceptual diagram showing the data amount of the distribution moving image content. Three cases from case (A) to (C) are described. In the figure, a represents the amount of reproduced data, and b represents the amount of buffered data. c represents the total data amount of the content.

  In the present embodiment, the band limitation target terminal is determined using three types of determination criteria A to C. As in case (A), the determination criterion A is to lower the distribution priority to the guest room terminal when the difference between the buffered data amount b and the reproduced data amount a is larger than a predetermined threshold. is there. The difference (b−a) in the data amount represents the amount of data that has been buffered but has not been viewed by the user. However, the band limitation can be executed without feeling uncomfortable with the band limitation.

  The determination criterion B is to increase the distribution priority to the guest room terminal when the difference between the total content amount c and the buffered data amount b is smaller than a predetermined threshold as in the case (B). is there. The difference (c−b) in the data amount corresponds to the amount of data until the end of moving image distribution. If the data amount is small, even if it is determined that the band limitation should be executed according to the determination criterion A. It is more reasonable to end the video distribution itself quickly without executing the bandwidth limitation.

  The criterion C, as in the case (C), lowers the distribution priority to the cabin terminal when the end roll start point is detected in the buffered data. Here, the end roll indicates the name of the person or organization involved in content production at the end of the main content of the video. Since it is considered that there are few users who are particular about the end-roll viewing quality, according to the criterion C, it is possible to more appropriately perform the band limitation without feeling uncomfortable with the band limitation.

  The end roll is displayed while scrolling a cast or the like in the vertical direction, and can be identified by image recognition. The playback unit 203 detects the start point of the end roll at regular intervals. That is, the playback unit 203 functions as an end roll detection unit. The target to be detected by the determination criterion C may be a target to be detected that “the end roll is being reproduced” in addition to the end roll start point. In the present embodiment, both of them are referred to as “end roll detection”.

  In addition, when the data management unit 302 of the management server 300 detects that the end roll start time of the content being played on the guest room terminal 200 is not known, the content management unit 302 detects that it is a certain time before the playback time, such as the remaining 10 minutes. The guest room terminal 200 is notified to execute the end roll monitoring function.

  The video management unit 101 manages the database of video data IDs, titles, data sizes, playback times, and the like, but when the playback unit 203 detects an end roll, the end roll start is performed in the database managed by the video management unit 101. Add time. The next time the same content is viewed on another terminal, this process can be omitted.

  In the present embodiment, as described with reference to FIG. 4, the determination of the bandwidth restriction target terminal based on the distribution priority (step S <b> 111 in FIG. 3) is performed based on the total content data amount, the buffered data amount, The distribution management unit 303 replaces these with information indicating the total time required for reproducing the entire content, information indicating the time required for reproducing the buffered content, and the time of the reproduced content. The determination may be performed based on information indicating the above.

  Note that the configurations disclosed in the above description of the embodiments can be combined with each other. For example, the determination criteria A, B, and C shown in FIG. 4 can be combined with each other.

DESCRIPTION OF SYMBOLS 100 VOD server 101 Image | video management part 102 Distribution control part 200 Room terminal 202 Storage part 203 Reproduction | regeneration part 205 Measurement part 208 Transmission part 300 Management server 302 Data management part 303 Distribution management part

Claims (9)

A video distribution system including a plurality of clients and a management server that distributes video to the clients,
The management server includes, among a plurality of clients, a total data amount of a distributed video and a client among a client in which a difference between a data amount of a moving image accumulated by the client and a reproduced data amount is larger than a predetermined threshold The video distribution system is characterized in that the bandwidth is limited by giving priority to a client whose difference from the data amount of the stored video is larger than a predetermined threshold . A video distribution system including a distribution server that distributes video, a client that receives and plays the distributed video, and a management server that controls the distribution server,
The distribution server
A distribution control unit that monitors a state of a band used for moving image distribution and transmits the state of the band to the management server;
The client
Storage means for storing the distributed video;
Playback means for playing back the accumulated video;
The data amount of video storage means has accumulated, and, and a transmitting means for transmitting the difference data amount of moving the data amount and the reproduction unit of the moving image which the storage means has accumulated is reproduced to the management server,
The management server
Data management means for managing the total data amount of the video distributed for each client;
In order from the client in which the difference in the amount of data received from the client is larger than a predetermined threshold , a low priority is assigned,
Among the clients to which the priority is given, the priority of the client in which the difference between the total data amount of the distributed moving image and the data amount of the moving image accumulated by the accumulating unit is smaller than a predetermined threshold is set to a high priority Updated to
Based on the state of the bandwidth received from the distribution server, it is determined whether or not to limit the bandwidth, and when it is determined that the bandwidth is to be limited, the bandwidth to be used for the video distribution to the low priority client is limited. Distribution management means for determining
The distribution control means of the distribution server includes:
A moving picture distribution system, wherein band limitation is executed based on the determination of the distribution management means. The client includes end roll detection means for detecting the start of the end roll from the moving image accumulated by the accumulation means,
The distribution management means of the management server includes:
The end role against the clients start the end role has been detected by the detecting means, the priority in which the distribution management unit has given, characterized in that the start of the end role is updated to a lower priority than clients that are not detected, according to claim 2 Symbol placement video distribution system. The distribution server
For each moving image to be distributed, the image management means stores the total data amount and the position of the start point of the end roll detected by the end roll detection means,
4. The moving image distribution system according to claim 3 , wherein the distribution management means of the management server reuses the position of the start point of the end roll stored in the video management means for priority setting. A bandwidth limiting method in a video distribution system including a distribution server that distributes a video, a client that receives and reproduces the distributed video, and a management server that controls the distribution server,
In the distribution server,
Monitor the status of bandwidth used for video distribution,
Sending the bandwidth status to the management server;
On the client,
Accumulate distributed videos,
Play the accumulated video,
Data amount of videos and the storage, and sends the difference of the data amount of the accumulated moving image and reproduced data amount of moving to the management server,
On the management server,
Manage the total amount of video data distributed to each client,
In order from the client in which the difference in the amount of data received from the client is larger than a predetermined threshold , a low priority is assigned,
Of the clients assigned the priority, the priority of the client whose difference between the total data amount of the distributed video and the accumulated video data is smaller than a predetermined threshold is updated to a higher priority. ,
Based on the state of the band received from the distribution server, determine whether to limit the bandwidth,
If it is determined to do so, it is determined that the bandwidth used for the video distribution to the low priority client is limited,
In the distribution server,
A band limiting method for a moving picture distribution system, wherein band limiting is performed based on a determination to limit a band used for moving picture distribution to a client having a low priority. A management server that distributes videos to multiple clients,
Among multiple clients, among clients whose difference between the amount of video data accumulated by the client and the amount of reproduced data is greater than a predetermined threshold , the total data amount of the distributed video and the video accumulated by the client A management server characterized by preferentially limiting a bandwidth to a client whose difference from the amount of data is larger than a predetermined threshold . For each client, the difference between the amount of moving image data accumulated by the client and the amount of reproduced movie data, and the difference between the total amount of moving image data distributed to each client and the amount of moving image data accumulated by the client Data management means for managing
In order from the client in which the difference between the data amount of the moving image accumulated by the client and the data amount of the reproduced moving image is larger than a predetermined threshold , a low priority is assigned,
Among the clients assigned with the priority, the priority of the client whose difference between the total data amount of the distributed moving image and the data amount of the moving image accumulated by the client is smaller than a predetermined threshold is updated to a high priority. ,
Based on the status of the bandwidth used for video distribution, it is determined whether or not to limit the bandwidth, and if it is determined, it is determined to limit the bandwidth used for video distribution to the low priority client. Distribution management means to
A management server comprising: To a computer that functions as a management server that distributes videos to multiple clients,
Among multiple clients, among clients whose difference between the amount of video data accumulated by the client and the amount of reproduced data is greater than a predetermined threshold , the total data amount of the distributed video and the video accumulated by the client A program for preferentially limiting a bandwidth to a client whose difference from the data amount is larger than a predetermined threshold . Computer
For each client, the difference between the amount of moving image data accumulated by the client and the amount of reproduced movie data, and the difference between the total amount of moving image data distributed to each client and the amount of moving image data accumulated by the client Data management means for managing
In order from the client in which the difference between the data amount of the moving image accumulated by the client and the data amount of the reproduced moving image is larger than a predetermined threshold , a low priority is assigned,
Among the clients with the priority, the priority of the client whose difference between the total data amount of the distributed video and the data amount of the video accumulated by the client is smaller than a predetermined threshold is updated to a higher priority. And
Based on the status of the bandwidth used for video distribution, it is determined whether or not to limit the bandwidth, and if it is determined, it is determined to limit the bandwidth used for video distribution to the low priority client. A program that functions as a distribution management means.

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