WO2005062566A1

WO2005062566A1 - Information transmission terminal and receiving terminal

Info

Publication number: WO2005062566A1
Application number: PCT/JP2003/016460
Authority: WO
Inventors: Yasuhiro Akiyama
Original assignee: Hitachi, Ltd.
Priority date: 2003-12-22
Filing date: 2003-12-22
Publication date: 2005-07-07
Also published as: JPWO2005062566A1

Abstract

An information transmission terminal for use in a content delivery system performing streaming service of a video or voice content for a receiving terminal. A delivery server grasps the residual quantity of streaming data of all receiving terminals under management and provides a system capable of stabilized streaming by assigning to a receiving terminal, where a reproduction trouble, e.g. depletion of content data, may possibly occur, a communication band preferentially to other receiving terminals operating stably, thereby avoiding reproduction trouble.

Description

Description Information transmitting terminal and receiving terminal Technical field to which the invention pertains

The present invention relates to an information transmitting device and a receiving terminal used in a content distribution system that distributes content data. Background art

In recent years, with the rapid rise of broadband technology, mobile phones and PDAs (Personal

With the spread of mobile terminals (hereinafter referred to as “receiving terminals”) such as Digital Assistance, video and audio streaming services using wireless infrastructure such as a cellular telephone communication network and wireless LAN (Local Area Network) Is expanding. A major feature of streaming for these receiving terminals is that they can view the content while the receiving terminal is moving. One example of wireless infrastructure technology is a cellular mobile communication system.

In a cellular mobile communication system, when a receiving terminal moves between cells, a "handover process" for automatically switching a wireless channel between a wireless base station and a receiving terminal is executed. When performing streaming in this cellular mobile communication system, the interruption of communication due to the handover process, that is, the interruption of streaming becomes a problem. Therefore, by securing streaming data for a certain period of time in advance in the buffer of the receiving terminal as backup data, the interruption of communication due to handover is temporarily concealed, and the user is not noticed of the interruption of communication. It is possible. However, there is a problem that if the movement between cells is repeated, the reserved data that has been used up is exhausted, and eventually streaming is interrupted at a certain point.

The following example is disclosed as a prior art of a distribution control method involving inter-cell movement of a wireless impulse or the like in a content distribution system.

The Japanese Patent Office published in Japanese Patent Application Publication No. 2000-2008 When the receiving terminal changes the data transmission speed from the server to the receiving terminal beyond the preset threshold, the target storage amount of content data, the delay time from writing to playback, the buffer occupancy, etc. It describes how to notify the server and control the communication speed of content data on the server side.

The Japanese Patent Office published in Japanese Patent Laid-Open Publication No. 2003-70054 published in 2003 stated that the server detected a receiving terminal that was about to perform a handover, and that it was present in the cell after the handover. A method is described in which a communication band is redistributed in accordance with predetermined conditions of all receiving terminals. The predetermined conditions of the receiving terminal include the contract fee structure, the communication band, the actual number of times of controlling the communication band, and the type of the distribution content. Disclosure of the invention

However, in the prior art disclosed in Japanese Patent Application Laid-Open No. 2002-834339, since the redistribution of the communication band of the server (or the radio base station) is not taken into account, a plurality of reception bands are not considered. There is a problem that it cannot respond to requests from terminals that exceed the server's communication capability.

Further, in the conventional technology disclosed in Japanese Patent Application Publication No. JP-A-2003-3000-4, the judgment conditions for redistributing the communication band are determined by the service such as the contract fee system and the actual number of times the communication band is controlled. Based on parameters different from the real-time communication status between ,ing. Therefore, there is a problem that the server cannot always cope with the situation where the receiving terminal largely depends on the latest communication state such as interruption of streaming due to handover. -According to the present invention, in a content distribution system for the purpose of streamer service using a communication line, the unreproduced buffer remaining in the content buffer unit or information corresponding thereto is distributed to the receiving terminal. A means for notifying the server is provided. Also, based on the information sent from the receiving terminal, the distribution server provides the receiving terminal with the less unreproduced buffer capacity to all receiving terminals under the same management including the notified terminal, based on the information sent from the receiving terminal. A means is provided for assigning priorities to higher priorities and redistributing communication bandwidth.

The distribution server sets the remaining amount of streaming data for all receiving terminals under its management. Figure out. Then, depending on the communication state, a communication band is allocated to a receiving terminal that is likely to cause a reproduction failure such as a content buffer exhaustion over other receiving terminals that are operating stably. As a result, it is possible to provide a system capable of avoiding a reproduction failure and performing stable streaming. Brief Description of Drawings

FIG. 1 is a block diagram showing a configuration of a content distribution system centered on distribution server 100 according to the embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of the receiving terminal 200 according to the embodiment of the present invention.

FIG. 3 is an explanatory diagram of the content of the content data stored in the content buffer unit 202 ′ of the receiving terminal 200 according to the embodiment of the present invention.

FIG. 4 is an explanatory diagram of the data remaining amount monitoring operation of the receiving terminal 200 according to the first embodiment of this invention. FIG. 4 (a) is a block diagram centering on the data remaining amount monitoring unit 207, and FIG. 6 is a graph showing a relationship with a transmission timing.

FIG. 5 is an explanatory diagram of the contents of the receiving terminal information 600 notified to the distribution server 100 according to the first embodiment of this invention.

FIG. 6 is an explanatory diagram illustrating another example of the content of the receiving terminal information notified to the distribution server 100 according to the first embodiment of this invention.

FIG. 5 is a flowchart showing the operation of the receiving terminal 200 according to the first embodiment of the present invention.

FIG. 8 is a flowchart showing the operation of the Tori S communication server 100 when receiving terminal information is received from the receiving terminal 200 according to the first embodiment of the present invention.

FIG. 9 is an explanatory diagram of the priority order determining operation performed in step 103 of FIG. 8 in the first embodiment of the present invention. FIG. 9 (a) shows the state immediately after the adjustment of the priority, and FIG. 9 (b) shows the state after the adjustment of the priority by the priority determination 107.

FIG. 10 illustrates a communication band allocating unit 1 of the distribution server 100 according to the second embodiment of this invention. 9 is a flowchart showing an operation of adjusting communication band allocation performed in 08.

FIG. 11 is an explanatory diagram of another example of the data remaining amount monitoring operation of the receiving terminal 200 according to the second embodiment of this invention. Fig. 11 (a) is a block diagram centering on the data remaining amount monitoring unit 207, and Fig. 11 (b) includes information on the data amount and the data remaining amount of the content buffer unit 202. 9 is a graph showing a relationship between reception terminal information and transmission timing.

FIG. 12 is a flowchart showing another example of the operation of the receiving terminal 200 according to the second embodiment of the present invention.

FIG. 13 is a flowchart showing another example of the operation of the distribution server 100 when receiving terminal information is notified from the receiving terminal 200 according to the second embodiment of the present invention. is there.

FIG. 14 is an explanatory diagram of the priority order determining operation performed in step 1206 of FIG. 13 in the second embodiment of the present invention. FIG. 14 (a) shows a state in which the priorities have been adjusted, and FIG. 14 (b) shows a state after the priorities have been adjusted by the priority determining unit 107.

FIG. 15 is an explanatory diagram of another example of the priority order determining operation performed in step 123 of FIG. 13 in the second embodiment of the present invention. FIG. 15 (a) shows the state immediately after the adjustment of the priority order, and FIG. 15 (b) shows the state after the adjustment of the priority order by the priority order determination unit 107.

FIG. 16 is a block diagram showing an example of an embodiment using the distribution server and the receiving terminal according to the second embodiment of the present invention.

FIG. 17 is a block diagram showing another example of the embodiment using the distribution server and the receiving terminal according to the second embodiment of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION

FIG. 1 is a block diagram showing the configuration of a content roster system centered on the distribution server 100 according to the present embodiment.

The distribution server (information communication device) 100 is communicably connected to the receiving terminal 200 via the communication network 111. The communication network 1 1 1 is composed of wireless communication lines. The Note that the communication network 111 is not limited to a wireless communication line, but may be a wired line or another type of network. Although only one receiving terminal 200 is shown in FIG. 1, actually, a plurality of receiving terminals 200 are provided, and the distribution server 100 is provided with a plurality of receiving terminals 200. It is connected. Further, the communication network 111 includes a relay station, and manages the receiving terminal 200 in units of the relay station.

A content storage unit 109 is connected to the distribution server 1◦0. The content storage unit 109 stores in advance content data such as 5 * 1 elephants and voices for communicating with the receiving terminal 200 by the streaming service.

In the distribution server 100, the content data is transmitted to the receiving terminal 200 in the following procedure.

The content input section 101 reads out the content data from the content storage section 109 and temporarily stores the read out content data in the content buffer section 102. The bucket generation unit 103 controls an increase or decrease in the amount of bucket generation for each content to be distributed, according to an instruction from the communication band allocation unit 108. For the amount of packet generation, an appropriate packet is generated according to, for example, the bandwidth of the communication network 111, the reproduction capability of the receiving terminal 200, and the like. Then, the generated packet is stored in the packet buffer 104. The transmission / reception unit 105 reads the bucket from the packet buffer unit 104 at a predetermined timing, and transmits the packet to the reception terminal 200 via the communication network 111.

When the distribution server 100 is transmitting a packet of content data to a plurality of receiving terminals 200, the distribution server 100 0 receives a predetermined notification from the receiving terminal 200. Accordingly, the allocation of the communication band of the plurality of receiving terminals 200 currently communicating with the distribution server 100 can be redistributed. The procedure is as follows.

When receiving the notification from the receiving terminal 200, the transmitting / receiving unit 105 receives the notification and stores the content of the notification in the receiving terminal information storage unit 106. Also, priority order information regarding the distribution of communication bands of the plurality of receiving terminals 200 currently communicating with the distribution server 100 is stored in the priority order management table 110.

The priority order determining unit 107 includes a receiving terminal information storage unit 106 and a priority order management table. Based on the information stored in communication terminal 110 and communication terminal 200, the priority of communication terminal 200 regarding communication band allocation is determined. The determined priorities are stored in the priority management table 110 and are notified to the communication band allocation unit 108. Communication band allocating section 108 adjusts the communication band of each receiving terminal 200 based on the determined priority, and controls bucket generating section 103 to control the amount of packet generation of transmitted content for each receiving terminal 200. I do.

FIG. 2 shows an embodiment of the present invention. FIG. 2 is a block diagram showing the configuration of the receiving terminal 200. The content transmitted by the distribution server 100 and received by the receiving terminal 200 is generally MPEG (Motion Picture E-mail) because of the easiness of data handling. Use data compressed by a predetermined coding method, such as xperts Group (AVper) and AV I (Audio Video Interleaved). The receiving terminal 200 receives the content data transmitted from the Tori S communication server 100 via the communication network 111.

The receiving terminal 200 reproduces the content received from the distribution server 100 according to the following procedure.

The transmission / reception unit 201 receives the content data transmitted from the distribution server 100 and stores it in the content buffer unit 202. The reproduction unit 203 reads out the content data from the content buffer unit 202 according to the reproduction speed of the content, and performs a predetermined decoding. Of the decrypted data, 1 * {elephant is displayed on the monitor 204, and voice is output to the speed 205.

The receiving terminal 200 has a function of monitoring the remaining data amount and notifying the distribution server in order to prevent the content data of the content buffer unit 202 from dying when receiving and reproducing the content data. The operation is as follows.

The remaining data monitoring unit 207 detects the remaining data in the content buffer unit 202 and outputs the information to the receiving terminal information generating unit 206. The detection of the remaining amount of data is performed at a predetermined timing with reference to the reference timer 208. The receiving terminal information generating unit 206 receives the remaining data amount detected by the remaining data monitoring unit 207, and adds the receiving terminal ID, the ID of the relay station currently communicating, the date and time of the message, and the like to this. And send it to the transmission / reception unit 201. The transmission / reception unit 201 transmits the reception terminal information to the distribution server 100.

FIG. 3 is an explanatory diagram of the content of the content data stored in the content buffer unit 202 of the receiving terminal 200 according to the embodiment of the present invention.

The content buffer unit 202 stores the content data sent from the distribution server. In the example of FIG. 3, the content buffer unit 202 configures one piece of content data from packets from A to C in the order in which the buckets are received, and stores them sequentially. During playback, the content data is read from A to C.

Now, it is assumed that all of A to C of the content buffer unit 202 are filled with the content data, and it is assumed that A to B have already been read by the content data reproduction processing. At this time, the remaining data amount that is detected by the data remaining amount monitoring unit 2007 and notified by the receiving terminal information generation unit 206 to the distribution server 100 is the unreproduced content data amount of B to C It becomes 1.

FIG. 4 is an explanatory diagram of the data remaining amount monitoring operation of the receiving terminal 200 according to the first embodiment of this invention. Fig. 4 (a) is a block diagram mainly showing the data remaining amount monitoring unit 20'7, and Fig. 4 (b) shows the receiving terminal information including information on the data amount and data remaining amount of the content buffer unit 202. 6 is a graph showing a relationship with the transmission timing of the data.

In FIG. 4A, the data remaining amount monitoring unit 207 monitors the data remaining amount of the content buffer unit 202 at predetermined intervals while referring to the reference timer 208. This predetermined interval is set in the monitoring interval setting unit 400 in advance.

FIG. 4 (b) shows an example of the operation of the data remaining amount monitoring unit 207. It is assumed that the predetermined interval for monitoring the remaining amount of data is set to “T” in advance. The data remaining amount monitoring unit 207 starts the content data reproduction from the content buffer unit 202 when the playback of the content data is started (401) and the time デ has elapsed (405). The amount is detected (402), and the information is sent to the receiving terminal information generator 206. The receiving terminal information generating unit 206 creates receiving terminal information from the received information, and notifies the distribution server 100 via the transmitting / receiving unit 201.

Next, the data remaining amount monitoring unit 2007 waits for more time after the first data remaining amount detection. When T has elapsed (406), the second data remaining amount is detected (403), and the information is notified to the distribution server 100. Thereafter, similarly, every time the time Τ elapses, the remaining amount of the content data is detected, and the receiving server information including the remaining amount information of the content data is notified to the distribution server.

The receiving terminal information 600 is information indicating the state of the receiving terminal, which is a criterion for determining the priority in the procedure of redistributing the communication bandwidth of the distribution server 1: 0.

In FIG. 5A, the receiving terminal information 600 includes a terminal ID 601 for identifying the receiving terminal 200, and a relay station that relays stream data communication (a relay station included in the communication network 111). Relay station ID 602 to identify the terminal, transmission date and time 603 of receiving terminal information 600, remaining amount of unplayed content data 604 of receiving terminal 200, and content bit rate indicating the playback speed of content data of receiving terminal 200 605, and the lower limit setting value 606 of the remaining data amount.

FIG. 5 (b) shows an example of the parameters set in the receiving terminal information 600 actually transmitted by the receiving terminal 200. In this example, the terminal ID 601 indicates “TMID-01234” (607). Also, it indicates that the relay station ID 602 is “BSID-56789” (608). The transmission date and time 603 is “2 0030101—123456” (609), which indicates 12:34:56 on January 1, 2003. Further, "" indicates that the remaining data amount 604 is "327680" yte (610). The content bit rate 605 is “131072” bps (611). The data remaining lower limit setting value 606 indicates “163840” by t e (612).

Upon receiving the receiving terminal information 600, the distribution server 100 divides the remaining data amount 604 by the content bit rate 605 to obtain the remaining playback time length (content preliminary playback time) of the content data. The rooster & f word server 100 determines the priority order of the plurality of receiving terminals 200 based on the value of the content preliminary reproduction time. FIG. 6 is a diagram showing reception terminal information notified to distribution server 100 according to the first embodiment of the present invention. It is explanatory drawing which shows another example of the content of a report.

In FIG. 6 (a), the receiving terminal information 700 is replaced by the remaining data amount 604, the content bit rate 605-5—, and the remaining data lower limit setting value 606 shown in FIG. 5 (a). , Content preliminary reproduction time 704, and content preliminary reproduction time lower limit setting value 705. The terminal IDs 701, 706, the relay station IDs 702, 707, and the transmission date / time 703, 708 are the same as the receiving terminal information 600 shown in FIG. Therefore, the description is omitted.

That is, in the embodiment shown in FIG. 6, since the content terminal preliminary reproduction time 704 is included in the reception terminal information 700, when the reception terminal information 700 is received, the reception It is not necessary to calculate the content preliminary playback time as described above in the terminal priority determination process. Therefore, there is an advantage that the processing load of the distribution server 100 is reduced.

FIG. 6 (b) shows an example of the parameters set in the receiving terminal information 700 that the receiving terminal 200 actually transmits. The content preliminary reproduction time 704 indicates that it is “20” seconds (709). Also, the content preliminary reproduction time lower limit setting value 705 indicates that it is “10” seconds (710). '

FIG. 7 is a flowchart showing the operation of the receiving terminal 200 according to the first embodiment of the present invention.

In the flowchart of FIG. 7, the receiving terminal information 600 is notified to the distribution server 100 at regular intervals, as described above with reference to FIG.

The data remaining amount monitoring unit 307 sets the monitoring time interval of the data remaining amount with reference to the contents set in the monitoring interval setting unit 400 (step 800).

Next, the monitoring timer operation is started in accordance with the signal from the reference timer 208 (step 801).

Next, streaming processing of the content is started (step 802). The transmission / reception unit 201 receives the content data sent from the distribution server 100 by the start of the streaming process (step 803). The received content is stored in the content buffer unit 202, and the content data is reproduced by the reproduction unit 203 (step 804). While the content data is being reproduced, the data remaining amount monitoring unit 207 determines whether or not the monitoring timer has reached the monitoring time of the data remaining amount (step 805). The data remaining amount monitoring unit 2007 determines that the monitoring time has been reached, and ^ indicates the remaining amount of the content buffer unit 202 as described above with reference to FIG. The information is sent to the receiving terminal information generator 206. The receiving terminal information generating unit 206 generates receiving terminal information from the received information, and notifies the distribution server 100 of the generated receiving terminal information via the transmitting / receiving unit 201 (step 806). . When the notification is completed, it is determined ^ ¹ that the streaming is to be continued (step 807).

Instead of the remaining amount of the content data, a preliminary content reproduction time may be notified as shown in FIG.

In step 805, if the remaining data monitoring unit 207 determines that the monitoring time has not been reached, it does not notify the receiving terminal information (step 806) and continues the streaming. Move to judgment (step 807).

At step 807, it is determined whether or not the streaming is continued. If it is determined that the streaming will be continued, the content data reception processing (step 803) is performed.

On the other hand, if it is determined that streaming is not to be continued, the streaming process ends. Streaming is not continued ¾ ^ is, for example, when there is an instruction to end content data or a user's instruction to end streaming.

FIG. 8 is a flowchart showing the operation of distribution server 100 when receiving terminal information is notified from receiving terminal 200 according to the first embodiment of the present invention.

FIG. 8 shows a flowchart of the distribution server 100 connected to the reception terminal 200 that notifies the distribution server 100 of the reception terminal information 600 at regular intervals. It is assumed that distribution server 100 streams content data to a plurality of receiving terminals 200. In FIG. 8, a case will be described where the receiving terminal information is information (receiving terminal information 700) including the parameter of the preliminary reproduction time shown in FIG. First, the transmission / reception unit 105 determines whether or not the receiving terminal 200 has received a notification of the receiving terminal information (step 1000). It is determined that there is no incoming call: ^ executes the content transmission process (step 1 0 5), and The content data is streamed to the communication terminal 200. Then, a determination is made as to whether to continue streaming (step 1006).

On the other hand, in step 1000, when it is determined that there is an incoming notification of the receiving terminal information from receiving terminal 200, transmitting / receiving section 105 receives the receiving terminal information, analyzes it, and includes it in the receiving terminal information. The content preliminary reproduction time and other information are acquired, and the acquired information is stored in the receiving terminal information storage unit 106 (step 1001).

Next, the priority order determination unit 107 refers to the content preliminary reproduction time and the relay station ID stored in the reception terminal information storage unit 106. Then, the content preliminary reproduction time of all the receiving terminals 200 belonging to the relay station, indicated by the relay station ID, is obtained from the receiving terminal information storage unit 106, and these are compared (step 1002). The rank determining unit 107 determines the priority of the receiving terminal according to the comparison result (step 1003). Then, the priority is notified to the communication band allocation unit 108. The communication band allocation unit 108 reconstructs the communication band allocation of each receiving terminal based on the priority (Step 1004). Then, the bucket generation unit 103 controls the amount of packet generation of the content transmitted by each reception terminal 200.

Next, it is determined whether or not the force to continue the streaming (step 1006). If it is determined that the streaming is to be continued, the process proceeds to the reception determination of the reception terminal information (step 1001). If the age is determined not to continue streaming, the streaming process ends.

FIG. 9 is an explanatory diagram of the priority order determining operation performed in step 1003 of FIG. 8 in the embodiment of the present invention, wherein the distribution server 100 receives the receiving terminal A (1 10 1), the receiving terminal B ( 1 102), receiving terminal C (1 103) and receiving terminal D (1 10 4) based on the operation of the rooster S-communication server 100 shown in FIG. Here is an example of adjusting the priority.

Distribution server 10. In, the first priority position determination unit 107 adjusts the priority of the receiving terminal 200 using the priority management table 110. The priority management table 110 includes a receiving terminal ID and a content preliminary reproduction corresponding to the receiving terminal ID. It includes information on time, distribution bit rate, and lower limit value of preliminary playback time, and is configured by referring to the content of the receiving terminal information.

Fig. 9 (a) shows the state before the priority is adjusted. The receiving terminal A (1101) has the highest priority, the content preliminary reproduction time is 100 seconds, and the distribution bit rate is set to 128 kbps. Also, the receiving terminal D (1104) has the lowest priority, the content preliminary reproduction time is 5 seconds, and the distribution bit rate is set to 128 kbs.

Here, tj ^ assuming that the lower limit of the preliminary reproduction time of all the receiving terminals is 10 seconds, the receiving terminal D (1104) which is lower than the lower limit of the preliminary reproduction time, and the change of the communication band (change of the distribution bit rate). Be eligible.

Fig. 9 (b) shows the state after priority adjustment. The priority determining unit 107 sets the receiving terminal D (1104), which is below the lower limit of the preliminary reproduction time in FIG. 9A, to have the highest priority and to increase the communication band of the receiving terminal D (1104). Set. It is desirable to set the communication bandwidth to twice or more before adjustment. In the example of FIG. 9 (b), it is set to twice.

In addition, the priority determination unit 107 shifts the priority in the lower direction without changing the communication band, without changing the communication band, for the receiving terminal that is not less than the lower limit of the preliminary reproduction time in FIG. 9A. As a result, the receiving terminal D (1104) has the highest priority and the preliminary playback time remains at 5 seconds, but the distribution bit rate is set to 256 kbps.

FIG. 10 is a flowchart showing an operation of adjusting communication band allocation performed by communication band allocation section 108 of distribution server 100 according to the first embodiment of the present invention.

First, the communication band (distribution bit rate) of the receiving terminal that has been notified is set large (step 1500). It is desirable to set the communication bandwidth to at least twice the value before adjustment. In the example of Fig. 10, it is set to double.

Next, the sum of the distribution bit rates of all the receiving terminals belonging to the relay station indicated by the relay station ID is calculated, and this is set as “SBR” (step 1501).

Next, the maximum communication band capacity (transmission bit rate capacity) of the relay station is obtained, and this is obtained.

Set to “MRB” (step 1502). Next, the calculated SBR value is compared with the obtained MBR value to determine whether or not the MRB has exceeded the SRB (step 1503).

It is determined that the MBR is greater than the SBR ^, that is, the maximum communication bandwidth of the relay station is greater than the sum of the communication bandwidths of all the receiving terminals belonging to the Nakaito station. If there is still room in the communication band, the distribution bit rate of the terminal other than the notified receiving terminal is maintained as it is (step 1508). Then, the result is set so as to be maintained for a predetermined time (step 1507). In the example of FIG. 10, the predetermined time is 10 seconds. Then, the process ends.

If it is determined in step 1503 that the MBR is smaller than the SBR, that is, the sum of the communication bandwidths of all the receiving terminals belonging to the relay station exceeds the maximum communication bandwidth capability of the relay station. When the station's communication band is exhausted

. In this case, first, the total of the distribution bit rates of the receiving terminals 200 that have been notified is calculated, and this is set as “PBR” (step 1504). Next, the calculated PBR is subtracted from the MBR calculated in step 1502, and this is set as “TBR” (step 1505). Next, the calculated TRB, that is, the communication band usable by the receiving terminal 200 excluding the receiving terminal 200 whose priority order is changed is divided by the receiving terminal 200 other than the notified receiving terminal 200 into S. (Step 15 06). In this redistribution, the ratio of the distribution bit rate currently set to the receiving terminals 200 other than the receiving terminal 200 that has been notified is applied as it is.

Next, the reallocation result is set so as to be maintained for a predetermined time (step 1507). In the example of FIG. 10, the predetermined time is 10 seconds. Then, the process ends.

In step 1500, the change amount of the communication band may be any value that is twice or more. Also, in step 1507, the predetermined time for maintaining the reallocation result may be any time length.

Next, a second embodiment of the present invention will be described.

FIG. 11 is an explanatory diagram of another example of the remaining data amount monitoring operation of the receiving terminal 200 according to the second embodiment of the present invention. FIG. 11 (a) is a block diagram mainly showing the data remaining amount monitoring unit 207, and FIG. 11 (b) is the transmission timing of the receiving terminal information including the information of the data amount and the remaining data amount of the content buffer unit 202. Is a graph showing the relationship with The

In FIG. 11A, the data remaining amount monitoring unit 207 transmits the information to the distribution server when the data remaining amount in the content buffer unit 202 becomes equal to or less than a preset data amount (lower limit of the data remaining amount). Notify. The lower limit of the data remaining amount is set in advance to the data remaining amount lower limit setting value 500. This data remaining sculpture 500 power S is a condition for timing of notifying the distribution server of the remaining information of the content data. In FIG. 11 (b), the data remaining amount monitoring unit 207 continuously monitors (or at a predetermined short interval) the data remaining amount of the content buffer unit 202 immediately after the reproduction of the content data is started (501) (503). I do. The distribution server 100 is not notified while the remaining data is higher than the lower data limit setting value 500. Then, at the time when the remaining data amount falls below the data remaining lower limit setting value 500 (after the time T ′ has elapsed (504)), the data remaining amount monitoring unit 207 transmits the information, that is, the remaining amount of the content data ( = Data remaining lower limit value 500) to the receiving terminal information generating unit 206. The receiving terminal information generating unit 206 creates receiving terminal information from the received information, and notifies the distribution server 100 via the transmitting / receiving unit 201.

Also in the second embodiment, the receiving terminal information may include the remaining content data 604 (FIG. 5) or may include the content preliminary reproduction time 704 (FIG. 6). Good.

FIG. 12 is a flowchart illustrating another example of the operation of the receiving terminal 200 according to the second embodiment of the present invention.

In the flowchart of FIG. 12, when the remaining amount of data in the content buffer unit 202 becomes equal to or less than a preset data amount, the information is notified to the distribution server 100.

The data remaining amount monitoring unit 307 sets the lower limit value “TRG T IME” of the content preliminary playback time with reference to the data remaining amount lower limit setting value 500 (step 900). Next, the content streaming process is started. (Step 901). With the start of streaming, the transmission / reception unit 201 receives the content data sent from the distribution server 100 (step 902). The received content data The content data is stored in the content buffer unit 202, and the content data is reproduced by the reproduction unit 203 (step 903).

During the playback of the content data, the data remaining amount monitoring unit 207 calculates the content pre-play time, compares the calculated content pre-play time with the lower limit value “TRG—TIME”, and makes a comparison. As a result, it is determined whether or not the lower limit value “T RG— TI ME” is longer (multiple). The content preliminary reproduction time is calculated by detecting the remaining amount of content data in the content buffer unit 202 and dividing this by the value of the content bit rate.

If the content preliminary playback time is determined to be shorter (less) than the lower limit value “TRG—TIME”, the remaining amount of the content buffer unit 202 is detected, and the detected information is transferred to the content preliminary playback time (this At this time, the content preliminary reproduction time is equal to the lower limit value “T RG — Τ Ι ΜΕ”) is sent to the receiving terminal information generation unit 206. The receiving terminal information generating section 206 generates receiving terminal information from the received information, and notifies the generated receiving terminal information to the distribution server 100 via the transmitting / receiving section 201 (step 90). Five ) . When the notification is completed, the streaming judge is determined (step 906).

If it is determined in step 904 that the content preliminary playback time is longer (more than) the lower limit value TRG-T Ι の, the notification of the receiving terminal information is not performed (step 905), and the continuation of streaming is performed. Move to judgment (step 906).

In step 906, it is determined whether or not the ability to continue streaming is determined. If it is determined that the streaming is to be continued, the flow shifts to the content data reception processing (step 902). On the other hand, if it is determined that the streaming is not to be continued, the streaming processing ends.

Note that, without calculating the content preliminary reproduction time during the reproduction of the content data, the remaining content data is compared with a preset lower limit value of the content preliminary reproduction time, and the remaining content data is calculated in advance. If the content preliminary playback time is shorter (less) than the set content preliminary playback time, the information of the current content preliminary playback time may be notified to the distribution server 100.

FIG. 13 shows the communication of the receiving terminal information from the receiving terminal 200 according to the second embodiment of the present invention. 15 is a flowchart showing another example of the operation of the distribution server 100 when there is information.

FIG. 13 shows that, as described above, when the remaining amount of data in the content buffer unit 202 of the receiving terminal 200 becomes equal to or less than the preset data amount, the information is notified to the distribution server 100. This is a flowchart of the distribution server 100 connected to the receiving terminal 200. In FIG. 13, it is assumed that the receiving terminal information is information (receiving terminal information 700) including the parameter of the content preliminary reproduction time shown in FIG. First, the transmitting / receiving section 105 determines whether or not the receiving terminal 200 has received receiving terminal information (step 1200). If it is determined that there is no incoming call, content transmission processing is executed (step 1209), and content data is streamed to the streaming-receiving receiver terminal 200. Then, the processing shifts to the determination of the continuation of streaming (step 122).

On the other hand, if it is determined in step 12000 that there is an incoming notification of the receiving terminal information from the receiving terminal 200, the transmitting and receiving unit 105 transmits the receiving terminal information from the plurality of receiving terminals 200. It is determined whether or not there is an incoming call (step 1201). When the receiving terminal information notification is received only by the single receiving terminal 200, the receiving terminal information is received, analyzed, and the content preliminary reproduction time included in the receiving terminal information (FIG. 6) and other information, and stores the obtained information in the receiving terminal information storage unit 106 (step 125). -Next, the priority determining unit 107 sets the highest priority of the receiving terminal 200 that has received the notification (step 1206). Then, this priority is notified to the communication band allocation unit 108. The communication band allocation unit 108 reconstructs the communication band allocation of each receiving terminal based on the priority (step 1207). Then, the bucket generation unit 103 controls the amount of bucket generation of the content transmitted by each receiving terminal 200. In step 1221, if there is an incoming notification of the receiving terminal information from a plurality of receiving terminals, the transmitting / receiving section 105 sends the receiving terminal information to each of the plurality of notified receiving terminals. The information is acquired, and the acquired information is stored in the receiving terminal information storage unit 106 (step 122).

Next, the priority determination unit 107 determines the content of the receiving terminals 200 that have been notified. The preliminary reproduction time is compared (step 1203). The priority determining unit 107 determines the priority of the receiving terminal according to the comparison result. In the case of this flowchart, the priority of the receiving terminal 200 that has been notified is set to a higher order (step 1206). Then, this priority is notified to communication band allocation section 108. The communication band allocation unit 108 reconstructs the communication band allocation of each receiving terminal based on the priority (Step 1207). Then, packet generation section 103 controls the amount of packet generation of the content transmitted by each reception terminal 200.

Next, it is determined whether or not the streaming is continued (step 1208). If it is determined that the streaming is to be continued, the process proceeds to an incoming call determination of the receiving terminal information (step 1200). On the other hand, if it is determined that the streaming is not to be continued, the streaming process ends.

It should be noted that, in step 1201, whether or not a notification has been received from a plurality of receiving terminals may be determined `` simultaneously '' by determining whether or not there is an incoming call from a plurality of receiving terminals. Alternatively, it may be determined whether there is an incoming call from a plurality of receiving terminals “within a predetermined time”.

FIG. 14 is an explanatory diagram of the priority order determining operation performed in step 1206 of FIG. 13 in the second embodiment of the present invention. The receiving terminal A (1301), the receiving terminal B (1302), For the four receiving terminals, receiving terminal C (1303) and receiving terminal D (1304), of the operations of distribution server 100 shown in FIG. 13, the operation when a notification is received from a single receiving terminal is described. Here is an example of adjusting priorities based on this.

FIG. 14 (a) shows a state in which priorities have been adjusted. The receiving terminal A (1301) has the highest priority, the content preliminary reproduction time is 100 seconds, and the distribution bit rate is set to 128 kbps. Also, the receiving terminal D (1304) has the lowest priority, the preliminary reproduction time is 50 seconds, and the distribution bit rate is set to 128 kbps. Further, assuming that the lower limit of the preliminary reproduction time of all the receiving terminals is 10 seconds, the receiving terminal C (1303) is less than the lower limit of the preliminary reproducing time, and notifies the distribution server 100 of the receiving terminal information. Do.

Figure 14 (b) shows the priority j injection position adjusted in response to the notification from the receiving terminal C (1303). This shows the state after adjustment. Priority determining section 107 sets the highest priority of receiving terminal C (1303) that has been notified, and sets a large communication band of receiving terminal D (1104). It is desirable to set the communication bandwidth to twice or more before adjustment. In the example of Fig. 14 (b), it is set to double.

In addition, the priority determination unit 107 shifts the priority in the lower direction without changing the communication band for the terminal that has not received the notification and does not change the communication band. As a result, the receiving terminal C (1303) has the highest priority, the preliminary playback time is 5 seconds, and the distribution bit rate is set to 256 kbps.

FIG. 15 is an explanatory diagram of another example of the operation of the priority determination performed in step 1203 of FIG. 13, wherein the receiving terminal A (1301), the receiving terminal B (1302), the receiving terminal C (1303), For the four receiving terminals D (1304), the priority is adjusted based on the operation when the notification is received from a plurality of receiving terminals among the operations of the distribution server 100 shown in FIG. This is an example.

Fig. 15 (a) shows the state immediately before the priority adjustment. The receiving terminal A (1401) has the highest priority, the preliminary playback time is 100 seconds, and the distribution bit rate is set to 128 kbs. Further, the receiving terminal D (1404) has the lowest priority S, the preliminary reproduction time is 10 seconds, and the distribution bit rate is set to 128 kbps. Furthermore, assuming that the lower limit of the preliminary playback time for all receiving terminals is 20 seconds, the receiving terminals B (1402) and D (1404) are below the lower limit of the preliminary playing time, and The server 100 is notified of the receiving terminal information.

FIG. 15 (b) shows a state after the priorities have been adjusted in response to the notifications from the receiving terminals B (1402) and D (1404). First, the priority order determination unit 107 compares the preliminary playback times of the receiving terminal B (1402) and the receiving terminal D (1404) that have been notified. In the example in Fig. 15 (a), the pre-play time of receiving terminal D (1404) is shorter. Therefore, the priority of receiving terminal D (1404) is set to the highest priority, and the priority of receiving terminal B (1402) is set to the second priority. Furthermore, it is desirable to set the communication bandwidth of receiving terminal B (1402) and receiving terminal D (1404) to at least twice that before adjustment. In the example in Fig. 15 (b), The

Also, the priority determination unit 107, which has not received the notification and does not change the communication band, shifts the priority in the lower direction as it is. As a result, the receiving terminal D (1404) has the highest priority, the preliminary playback time is 10 seconds, and the distribution bit rate is set to 256 kbps. Further, the receiving terminal B (1402) has the second priority, the preliminary reproduction time is 15 seconds, and the distribution bit rate is set to 256 ks.

Next, an example of a specific embodiment to which the distribution server 100 and the receiving terminal 200 according to the present invention are applied will be described.

FIG. 16 is a block diagram showing an example of an embodiment using a distribution server and a receiving terminal.

A distribution server 1700 connected to the content storage device 1702 is connected to the public network 1706, the transmitting station A (1714), and the transmitting station B (1704). It is connected to a public network 1706 via a transmitting station B (1704) and a relay station A (1705).

The distribution server 1700 is connected to a TV receiver 1701 for receiving TV broadcasts and an external network 1703 such as the Internet. The distribution server 1700 stores content data input from the external public network 1703 and content data obtained by converting a TV program received by the TV receiver 1701 into a file format that can be distributed by a predetermined conversion method. To record.

Transmitting station A (1714) is connected to mopile terminals such as notebook PCs, PDAs, and mobile phones via wireless communication. In the distribution via the transmitting station A (1714), a mobile PC such as a notebook PC (1710), a PDA (1709), or a mobile phone 1708 receives and views the content data directly.

The public network 1706 transmits the content transmitted from the distribution server 1700 to the terminal 1715 via a wired line. Further, a relay station B (1707) is connected to the public network 1706, and the relay station B (1707) is connected to a mobile terminal such as a notebook PC, a PDA, or a mobile phone via a wireless line. As shown, the distribution server 1700 and the public network 1706 are connected via a wired line. Alternatively, they may be connected via a wireless link by the station B (1704) and the relay station A (1705).

In distribution via transmission station B (1704), the content data is received by the mopile terminals (1711-1713, 1715) via relay station A (1705), public network 1706, and relay station B (1707). Watch.

Content data captured from the external public network 1703 or the TV receiver 1701 is distributed in real time in response to a request from a mopile terminal. In addition, content data fetched from the external public network 1703 or the TV receiver 1701 is stored in the content storage device 1702, and the content data is distributed as appropriate in response to a request from the mobile terminal. May be.

As described above, the present invention can be configured to distribute content data from a distribution server via a plurality of transmission stations, relay stations, and wireless networks in each distribution path. Therefore, if a communication failure or delay occurs in any of the distribution routes, the content buffer is likely to be exhausted by transmitting the content preliminary playback time of the receiving terminal receiving the content to the distribution server. The priority of the receiving terminal can be increased.

FIG. 17 is a block diagram showing another example of the embodiment using a force distribution server and a receiving terminal similar to FIG.

A distribution server 1612 connected to the content storage device 1613 is connected to the wireless transmission station 1614. The wireless transmission station 1614 is wirelessly connected to a plurality of wireless relay stations (1600 to 1602). Each of the radio relay stations (1600 to 1602) has a coverage area (cell) (1609 to 1611) within a predetermined range, and is wirelessly connected to a receiving terminal (1603A to 1608E) in the coverage area. I have. Receiving terminal A (1603) is moving in the coverage area of a plurality of wireless relay stations.

In the example of FIG. 17, the priority adjustment operation of the receiving terminal and the restructuring operation of the communication band allocation are performed on the receiving terminal existing within the coverage area of each wireless relay station. For example, the cover relay 1609 of the radio relay station 1600 is implemented for the receiving terminal A (1603), the receiving terminal B (1604), and the receiving terminal C (1605). The

Therefore, when the receiving terminal moves through the coverage area (cell), a handover process for automatically switching the radio channel occurs, but a communication interruption, that is, a streaming interruption accompanying the handover process occurs. Therefore, by transmitting the content preliminary playback time of the receiving terminal receiving the content to the distribution server, the priority of the receiving terminal whose content buffer is likely to be exhausted can be increased.

As described above, the present invention can be applied to any of a streaming distribution system using a wireless network, a streaming roster system using an existing II network, and a streaming distribution system using both networks. Industrial applicability

INDUSTRIAL APPLICABILITY The present invention can be used for a receiving terminal using a communication network in which a communication state changes, and for a content distribution system in which a streamer service of audio content is implemented. It is suitable to be applied to a communication system in which the communication state changes as described above, or a tsushin system in which communication is temporarily interrupted at the time of handover such as a cellular mobile communication network.

Claims

The scope of the claims

1. A transmitting / receiving unit that transmits information to a plurality of receiving terminals and receives a notification of the remaining playback time of the receiving terminal from at least one of the tflf own receiving terminals;

A priority for deciding the priority of information transmission to the lift self-receiving terminal based on the remaining terminal reproduction time notification received from the receiving terminal information storage unit for storing the remaining reproduction time notification received from the receiving terminal, and the remaining reproduction time notification received from the aversion receiving terminal. A ranking determiner,

A priority management table storing the determined priority;

A communication band allocating unit that allocates a band used for transmitting information to each of the receiving terminals in accordance with the determined priority.

The information transmission device, wherein the disgusting transmission / reception unit transmits information to the plurality of receiving terminals based on a bandwidth allocated to the user.

2. The information transmission according to claim 1, wherein the transmission / reception unit transmits information to the reception terminal via a wireless communication line, and receives a notification of a remaining reproduction time from the reception terminal. apparatus.

3. The band allocating unit extracts a receiving terminal whose remaining reproduction time received from the receiving terminal is shorter than a predetermined time,

2. The information communication apparatus according to claim 1, wherein the tiff self-priority is determined such that a band is preferentially allocated to the receiving terminal from which the t & lB has been extracted.

4. The transmission / reception unit according to claim 1, wherein the reception terminal receives an unreproduced amount of information stored in the reception terminal and transmitted in place of a remaining time of information reproduction. Information communication device.

5. The priority order determining unit, upon receiving the remaining playback time notification from any of the receiving terminals, determines the priority order of the information words to the vengeful receiving terminal. The information communication device according to claim 1, wherein

6. The information communication terminal according to claim 1, wherein the transmission / reception unit receives the notification of the remaining reproduction time transmitted by the reception terminal at a predetermined interval.

7. The transmission / reception unit receives a notification of the tin remaining time transmitted based on a comparison result between the unreproduced information amount accumulated in the reception terminal and a predetermined value. An information communication terminal according to item 1 of the range.

8. a transmitting / receiving unit that transmits information to a plurality of receiving terminals and receives a notification of a remaining reproduction time of the receiving terminal from at least one of the receiving terminals;

A receiving terminal information storage unit for storing the remaining playback time notification received from the receiving terminal, and tfrlB a priority for determining the priority of information transmission to a plurality of receiving terminals based on the remaining playing time notification received from the receiving terminal. A ranking determiner,

A priority management table for storing the priority determined by selfishness,

The receiving terminal is characterized in that the transmitting / receiving unit is connected to an information transmitting device that transmits information to a plurality of receiving terminals and receives the transmitted information, based on the band assigned by the lift.

9. The receiving terminal according to claim 8, wherein the receiving terminal is connected to the information communication device via a wireless communication line.

10. The information communication terminal according to claim 8, wherein the notification of the remaining reproduction time is transmitted at predetermined time intervals.

1 1. Based on the comparison result between the unreproduced information amount transmitted from the knitting information transmitting device and accumulated in the buffer and a predetermined value, the tins remaining reproduction time is notified based on the comparison result. Receiving end according to claim 8