JP6709624B2 - Content distribution system, video stream fragment posting method, and video stream fragment posting program - Google Patents

Description

The present invention relates to a content distribution system.

2. Description of the Related Art In recent years, with the rapid spread of user terminals such as smartphones, the performance has been improved, and a user who owns a user terminal can connect to the Internet from any place and receive various services. Many services are provided via base stations near the user.

On the Internet, a moving image service is provided by using various applications such as YouTube (trademark) and NicoNico video (trademark). Such streaming video distribution services have become popular along with the spread of the Internet and the spread of CDNs (Content Delivery Networks). If HTTP is used, caches can be used and firewalls and NATs can be easily crossed. Delivery using HTTP/TCP is becoming mainstream because it has the advantage of being able to easily prepare a server.

In addition, due to the advancement of information and communication technology, the application of wireless LAN devices has spread not only to office computers and networks but also to general households as the price of devices having wireless functions has dropped, and the characteristics of wireless LAN are A public wireless LAN service for connecting a wireless LAN to a public network has been started by taking advantage of the portability of a certain wireless terminal such as a smartphone, and it has become commonplace to use the wireless LAN in a city or a store. As a result, it has become possible to connect to the Internet via a wireless LAN in various places, and there are increasing opportunities to use the Internet. Since a wireless LAN normally does not require connection of a LAN cable, if there is an access point (AP), the Internet can be used regardless of the location.

Here, with the spread of the Internet, many new Internet media such as SNS (Social Network Service) such as Twitter (trademark) and Facebook (trademark) are spreading. Services that link various media deployed on the Internet have also appeared. Coordination and synchronization of these multiple Internet media and media streams such as moving image services are essential for realizing new services on the Internet.

Under such circumstances, there is a demand for a content distribution system capable of achieving cooperation and synchronization between the new Internet media and the video distribution service by a simple method using a high-performance user terminal such as a smartphone. ..

For example, in Patent Document 1, a collection unit that collects posts about posting targets that progress over time, a collection unit that collects the number of collected posts for each predetermined class, and a time series of the number of posts for each class. A moving image content including a display control unit that controls a plurality of graphs showing transitions to be displayed along a time axis together with additional information that is information including at least one of information about posts or posting targets at each time. It teaches an information processing apparatus that can easily grasp the transition of the posting tendency of a posting target that progresses with time.

JP, 2013-033375, A

However, Patent Document 1 does not describe a method of storing content on the server side, which is distributed by a server to a client, a method of distributing content, and a method of posting an object to be posted.

Therefore, the service provided by the information processing device of Patent Document 1 uses only the client to post a video stream fragment at an arbitrary position of the real-time video stream to the SNS site while the client is watching the real-time video stream. It does not make it possible in a simple and easy way.

Therefore, according to a first aspect of the present invention, the present invention provides a content distribution system including a user terminal connected to a communication network, a content provider, and an SNS service provider,
The content provider receives means for storing a real-time video stream including a plurality of video stream fragments, and a selection signal of the video stream fragment B from the first user terminal that transmitted the real-time video stream A, and the video stream fragment B. And a means for transmitting the stored video stream fragment B to the second user terminal in response to the notification of the browsing request for the video stream fragment B transmitted from the SNS service provider.
As the first user terminal, the user terminal receives the user input for selecting the video stream fragment B during the reproduction of the real-time video stream A transmitted from the content provider, and the user terminal related to the video stream fragment B. The video stream fragment B includes means for transmitting a selection signal to the content provider, means for transmitting a posting request for the video stream fragment B to the SNS service provider together with a message C, and the video stream fragment B as the second user terminal. Means for transmitting the browsing request to the SNS service provider, and the video stream fragment B transmitted from the content provider while displaying the message C transmitted from the SNS service provider in response to the browsing request. And means for reproducing,
The SNS service provider stores the message C transmitted together with the posting request from the first user terminal, publishes the message C in the user terminal, and stores the message C in the user terminal. Means for transmitting the message C to the second user terminal in response to a browsing request for the video stream fragment B from the user terminal, and transmitting a notification of the browsing request for the video stream fragment B to the content provider. With
It is a content distribution system.

According to a second aspect of the present invention, the present invention is a content distribution system including a user terminal connected to a communication network, a content provider, and an SNS service provider,
The content provider receives means for storing a real-time video stream including a plurality of video stream fragments, and a selection signal of the video stream fragment B from the first user terminal that transmitted the real-time video stream A, and the video stream fragment B. To store the posting request for the video stream fragment B and the message C sent from the first user terminal to the SNS service provider, and to send the request from the second user terminal. Upon receiving a browsing request for the video stream fragment B and the message C, means for transmitting the browsing request and the stored video stream fragment B to the SNS service provider,
As the first user terminal, the user terminal receives the user input for selecting the video stream fragment B during the reproduction of the real-time video stream A transmitted from the content provider, and the user terminal related to the video stream fragment B. A means for transmitting a selection signal to the content provider, a means for transmitting a posting request for the video stream fragment B to the content provider together with a message C, and the video stream fragment B as the second user terminal A means for transmitting a browsing request for the message C to the content provider, and the message C and the video stream fragment B when the SNS service provider transmits the browsing request as a source. And means for playing back the video stream fragment B,
The SNS service provider stores the posting request of the video stream fragment B transferred from the content provider and the message C, publishes the message C to the user terminal, and the content provider. Means for transmitting the video stream fragment B and the message C to the second user terminal upon receiving the browsing request for the video stream fragment B and the message C transmitted from With and
It is a content distribution system.

Furthermore, according to a third aspect of the invention, the invention comprises a user terminal connected to a communication network, a content provider storing a real-time video stream comprising a plurality of video stream fragments and an SNS service provider. A method of posting the video stream fragment to the SNS service provider by a content distribution system, the method comprising :
The first user terminal receiving the real-time video stream A from the content provider transmits a selection signal of the video stream fragment B,
The content provider receives the selection signal of the video stream fragment B and stores the video stream fragment B,
The first user terminal sends a posting request of the video stream fragment B to the SNS service provider together with a message C,
The SNS service provider stores the message C transmitted together with the posting request from the first user terminal, and posts the message C to the user terminal,
A second user terminal sends a viewing request for the video stream fragment B to the SNS service provider,
The SNS service provider sends the message C to the second user terminal in response to the viewing request for the video stream fragment B from the second user terminal, and notifies the viewing request for the video stream fragment B. To the content provider,
The content provider transmits the stored video stream fragment B to the second user terminal in response to the notification of the browsing request for the video stream fragment B transmitted from the SNS service provider,
The second user terminal displays the message C sent from the SNS service provider and plays the video stream fragment B sent from the content provider .
This is how to post a video stream fragment .

According to a fourth aspect of the present invention, the present invention provides a content distribution including a user terminal connected to a communication network, a content provider storing a real-time video stream including a plurality of video stream fragments, and an SNS service provider. A method for posting the video stream fragment to the SNS service provider by a system, comprising :
The first user terminal receiving the real-time video stream A from the content provider transmits a selection signal of the video stream fragment B,
The content provider receives the selection signal of the video stream fragment B and stores the video stream fragment B,
The first user terminal sends a posting request for the video stream fragment B with the message C to the content provider,
The content provider transfers the posting request of the video stream fragment B and the message C transmitted from the first user terminal to the SNS service provider,
The SNS service provider stores a posting request of the video stream fragment B transferred from the content provider and a message C, and posts the message C to the user terminal,
A second user terminal sends a viewing request for the video stream fragment B and the message C to the content provider;
When the content provider receives a browsing request for the video stream fragment B and the message C transmitted from the second user terminal, the content provider transmits the browsing request and the stored video stream fragment B to the SNS service provider. Then
When the SNS service provider receives the browse request for the video stream fragment B and the message C transmitted from the content provider and the video stream fragment B, the SNS service provider receives the video stream fragment B and the message C. Send it to the second user terminal,
When the message C and the video stream fragment B are transmitted from the SNS service provider, the second user terminal displays the message C and reproduces the video stream fragment B.
This is how to post a video stream fragment .

According to a fifth aspect of the present invention, the present invention relates to a user terminal, a content provider storing a real-time video stream including a plurality of video stream fragments, and a SNS service connected to a communication network to form a content distribution system. By being processed by the provider,
Causing a first user terminal, which has received the real-time video stream A from the content provider, to transmit a selection signal of a video stream fragment B;
Causing the content provider to receive a selection signal of the video stream fragment B and store the video stream fragment B;
The first user terminal sending a posting request for the video stream fragment B with the message C to the content provider;
Causing the content provider to transfer the posting request of the video stream fragment B and the message C transmitted from the first user terminal to the SNS service provider;
Causing the SNS service provider to store a posting request of the video stream fragment B transferred from the content provider and a message C, and posting the message C to the user terminal;
Causing a second user terminal to send a browsing request for the video stream fragment B and the message C to the content provider;
The content provider is caused to receive a browsing request for the video stream fragment B and the message C transmitted from the second user terminal, and the SNS service provider stores the browsing request and the stored video stream fragment. Sending B,
The SNS service provider is caused to receive the browsing request for the video stream fragment B and the message C and the video stream fragment B transmitted from the content provider, and the video stream fragment B and the message C are received. Causing the second user terminal to transmit,
When the message C and the video stream fragment B are transmitted from the SNS service provider to the second user terminal, displaying the message C and reproducing the video stream fragment B,
Is a video stream fragment posting program that executes .

According to a sixth aspect of the present invention, the present invention relates to a user terminal, a content provider storing a real-time video stream including a plurality of video stream fragments, and a SNS service connected to a communication network to form a content distribution system. By being processed by the provider,
Causing a first user terminal, which has received the real-time video stream A from the content provider, to transmit a selection signal of a video stream fragment B;
Causing the content provider to receive a selection signal of the video stream fragment B and store the video stream fragment B;
Causing the first user terminal to send a posting request for the video stream fragment B to the content provider along with a message C,
Causing the content provider to transfer the posting request of the video stream fragment B and the message C transmitted from the first user terminal to the SNS service provider;
Causing the SNS service provider to store the posting request of the video stream fragment B transferred from the content provider and the message C, and causing the message C to be posted to the user terminal;
Causing a second user terminal to send a browsing request for the video stream fragment B and the message C to the content provider;
The content provider is caused to receive a browsing request for the video stream fragment B and the message C transmitted from the second user terminal, and the SNS service provider stores the browsing request and the stored video stream fragment B. To send
The SNS service provider is caused to receive a browsing request for the video stream fragment B and the message C transmitted from the content provider, and the video stream fragment B, and the video stream fragment B and the message C are received. Is transmitted to the second user terminal,
When the message C and the video stream fragment B are transmitted from the SNS service provider to the second user terminal, displaying the message C and reproducing the video stream fragment B,
Is a video stream fragment posting program that executes .

According to the present invention, by using only a user terminal, posting a video stream fragment at an arbitrary position of the real time video stream to an SNS site while viewing the real time video stream on the user terminal is a simple method. It becomes possible with.

It is a figure which shows the whole structure of the wireless-communications network for implementing the content delivery system according to this invention. It is a figure which shows the structure of the mobile communication network 104. It is a functional block diagram of user terminal 118-i. It is a figure which shows the hardware constitutions of the content delivery server 122. It is a figure which shows the hardware constitutions of the database server 124. It is a figure which shows the hardware constitutions of the SNS server 128. It is a figure which shows the hardware constitutions of the database server 130. It is a figure which shows the hardware constitutions of Web server 120 and 126. It is a functional block diagram of an OFDM modulation/demodulation unit. It is a figure which shows a mode that a real-time video stream is stored in the content database 510 of the database server 124. It is a figure which shows delivery of the real-time video stream according to a RTP(Real Time Transport) protocol. It is a figure which shows the data structure of an RTP packet. FIG. 5 is a diagram illustrating HTTP Live Streaming (HLS) protocol streaming. It is a sequence diagram which shows the establishment of the session between the user terminal 118-i and the content delivery server 122. It is a flowchart of the adaptive bit allocation process performed between NodeB110 or eNodeB112 and user terminal 118-i. It is a figure which shows the display part 210 of the user terminal 118-i which displayed the real time program guide. It is a figure which shows the structure of the layered type QoS (Quality of Service) control function according to the RTP protocol. It is a figure which shows the structure of the QoS control function according to an HTTP Live Streaming (HLS) protocol. It is a sequence diagram of a symbol rate (bandwidth) negotiation performed between the content distribution server 122 and the user terminal 118-i. 9 is a flowchart of a zapping operation during viewing a program on the user terminal 118-i. It is a figure which shows the mode of zapping of the horizontal direction (longitudinal direction) on the display part 210 of the user terminal 118-i. It is a figure which shows the mode of zapping of the horizontal direction (longitudinal direction) on the display part 210 of the user terminal 118-i. It is a figure which shows the mode of vertical zapping on the display part 210 of the user terminal 118-i. It is a sequence diagram which shows 1st Embodiment of spreading|diffusion of a video stream fragment to SNS. It is a sequence diagram which shows 2nd Embodiment of spreading|diffusion of a video stream fragment to SNS. It is a sequence diagram which shows 3rd Embodiment of spreading|diffusion of a video stream fragment to SNS. It is a figure which shows operation at the time of posting the video stream fragment corresponding to the designated reproduction time on an SNS site. It is a figure which shows operation at the time of posting the video stream fragment corresponding to the designated reproduction time on an SNS site. It is a figure which shows operation at the time of posting the video stream fragment corresponding to the designated reproduction time on an SNS site.

While the invention is susceptible to various modifications and alternative forms, example embodiments of the invention are shown in the drawings by way of example and will be described in detail herein. However, the description herein of example embodiments is not intended to limit the invention to the particular forms disclosed, as the invention does not depart from the invention defined by the claims. Includes all modifications, equivalents, and alternatives falling within the spirit and scope.

(1) Overall Network Configuration FIG. 1 is a diagram showing an overall configuration of a wireless communication network for implementing the content distribution system according to the present embodiment.

The wireless communication network 100 includes a higher level network 102 that functions as a core network and a plurality of mobile communication networks 104. The core network 102 may include multiple content service routers 106, and the multiple mobile communication networks 104 may each include a radio network controller (RNC) 108, multiple NodeBs 110, and multiple eNodeBs 112. A content provider 114 that distributes content such as a real-time video stream, and an SNS service provider 116 that provides Social Network Services (SNS) such as Twitter and Line are connected to the higher-level network 102, and a plurality of user terminals 118-i (i= 1,..., N) are connected to a plurality of mobile communication networks 104. Here, the index i of the user terminal corresponds to the user id.

The content provider 114 includes a web server 120, a content distribution server 122, and a database server 124, and the SNS service provider 116 includes a web server 126, an SNS server 128, and a database server 130.

User terminals 118-i are smartphones, tablet terminals, cellular phones, personal digital assistants, text messaging devices, pagers, network interface cards, notebook computers, desktop computers, and personal digital assistants (PDAs). May be. User terminals 118-i can communicate by exchanging information over an air interface (or wireless communication link) that includes a number of communication channels, such as traffic channels, signaling channels, paging channels, etc. ..

The core network 102 may be a circuit switched network such as the public switched telephone network (PSTN) or a packet based network such as the Internet. Core network 102 includes, at least in part, any mobile communication network 104 that provides data communication via wireless signals. Mobile communication network 104 includes, for example, a wireless local area network (WLAN) using WiFi/WiMax communication. An exemplary implementation of mobile communication network 104 may be that implemented as a corporate network on a company or campus, or as a "hot spot" in a typical public venue such as an airport, coffee shop, or the like. Mobile communication network 104 further includes one or more access points that provide wireless connectivity to a plurality of user terminals 118-i. Access points include base stations, base station routers, and access networks.

The air interface communication channel is defined according to one or more wireless communication protocols used by the core network 102 or the mobile communication network 104. Core network 102 and mobile communication network 104 are typically used for data communications, but may be networks capable of forwarding voice communications such as VoIP calls. For example, core network 102 and mobile communication network 104 may be widely deployed to provide various communication services such as voice, video, packet data, messaging, broadcast and the like. These communication networks may be multiple access networks capable of supporting multiple user terminals by sharing the available network resources. Such multiple access networks include, for example, code division multiple access (CDMA) networks, time division multiple access (TDMA) networks, frequency division multiple access (FDMA) networks, orthogonal frequency division multiple access (OFDMA) networks, and single carrier. Includes Frequency Division Multiple Access (SC-FDMA) networks. For example, an air interface communication channel operating according to code division multiple access (CDMA) is defined by an orthogonal code that modulates a radio signal used to transmit information over the air interface. The communication channel of the air interface may also be determined by the frequency of the carrier used to transmit information over the air interface. For example, in Orthogonal Frequency Division Multiple Access (OFDMA), one or more user terminals 118-i may share multiple orthogonal frequencies or tones.

Here, the terms "network" and "system" are often used interchangeably. A CDMA network may implement a radio technology such as Universal Terrestrial Radio Access (UTRA), CDMA2000, etc. UTRA includes Wideband CDMA (WCDMA) and other variants of CDMA. CDMA2000 covers IS-2000, IS-95 and IS-856 standards. TDMA networks may implement wireless technologies such as Global System for Mobile Communications (GSM). The OFDMA network shall implement wireless technologies such as Evolved UTRA (E-UTRA), Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash OFDMA. You can UTRA and E-UTRA are part of the Universal Mobile Telecommunications System (UMTS). 3GPP Long Term Evolution (LTE) and LTE Advanced (LTE-A) are newly released UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, and GSM are described in "3rd Generation Partnership Project" (3GPP). CDMA2000 and UMB are described in "3rd Generation Partnership Project 2" (3GPP2).

FIG. 2 is a diagram showing the configuration of the mobile communication network 104.

Mobile communication network 104 may include multiple NodeBs 110, multiple eNodeBs 112, a radio network controller (RNC) 108, and other network entities. NodeB 110 and eNodeB 112 are stations that communicate with user terminals 118-i and are sometimes referred to as base stations, access points, or other terminology. Each NodeB-1 to NodeB-3 can provide radio coverage to a macro cell, which is a specific geographical area.

A macro cell can cover a relatively large geographical area (a few kilometers in radius) and allows unrestricted access by user terminals 118-i subscribing to the service. Each eNodeB 112 can provide radio coverage to relatively small geographical areas such as femtocells and picocells, allowing unrestricted access by user terminals 118-i subscribing to the service. A femtocell is restricted by a user terminal 118-i, such as a user terminal 118-i in a limited subscriber group (CSG) that has an association with the femtocell, or a user terminal 118-i for a home user. Allow access. The eNodeB 112 that handles a femto cell (Serving) may be referred to as a femto eNodeB or a home eNodeB (HNB), and the eNodeB that handles a pico cell may be referred to as a pico eNodeB. In the example of FIG. 2, NodeB-1, NodeB-2, and NodeB-3 may be macro NodeBs that handle macro cells 132, 134, and 136, respectively. Four of the eNodeBs 112 are femto eNodeBs that handle femtocells, and the other one of the eNodeBs 112 is a pico eNodeB that handles picocells.

The mobile communication network 104 may be a heterogeneous network including various types of eNodeBs, relays, and the like. These different types of eNodeBs may have different transmit power levels, different coverage areas, and different impact on mobile communication network 104 interference. For example, macro NodeBs may have high transmit power levels (20 Watts), while pico eNodeBs, femto eNodeBs, and relays may have lower transmit power levels (1 Watt). In FIG. 2, a solid line with a double-headed arrow indicates communication between the user terminal 118-i and the NodeB 110 or eNodeB 112 that handles the user terminal 118-i (Serving) via the downlink and the uplink. A signal with a double arrow is shown.

The mobile communication network 104 can support synchronous or asynchronous operation. For synchronous operation, the NodeB and eNodeB may have similar frame timing, and transmissions from different eNodeBs may be approximately temporally aligned. In the case of asynchronous operation, the eNodeBs may have different frame timings and the transmissions from different eNodeBs may not be time aligned.

The RNC 108 is connected to the NodeB 110 and the eNodeB 112 via a wireless link, and controls the NodeB 110 and the eNodeB 112. The RNC 108 can communicate with the NodeB 110 and the eNodeB 112 via the core network 102 (backhaul network). The NodeB 110 and the eNodeB 112 can communicate with each other directly or indirectly via a wireless backhaul or a wired backhaul.

LTE typically utilizes orthogonal frequency division multiplexing (OFDM) on the downlink and often single carrier frequency division multiplexing (SC-FDM) on the uplink. OFDM and SC-FDM partition the system bandwidth into multiple orthogonal subcarriers, commonly referred to as tones. Each subcarrier may be modulated with data. Modulation symbols are typically transmitted in the frequency domain with OFDM and in the time domain with SC-FDM. The spacing between adjacent subcarriers may be fixed and the total number of subcarriers depends on the system bandwidth. The number of subcarriers per system bandwidth is 128, 256, 512, 1024, or 2048 for the system bandwidth of 1.25, 2.5, 5, 10, or 20 [MHz], respectively. May be. The system bandwidth can be composed of multiple subbands. The sub-bands can cover, for example, 1.08 [MHz], and for system bandwidths of 1.25, 2.5, 5, 10, or 20 [MHz], one, two, respectively. There are 4, 8 or 16 subbands.

(2) User Terminal FIG. 3 is a functional block diagram of the user terminal 118-i.

The user terminal 200 includes a digital processing unit 202, a baseband unit 204, and an RF unit 206. Digital processing unit 202 includes an input unit 208, a display unit 210, a storage device 212, a memory 214, and a CPU 216. The CPU 216 realizes various functions by reading the program stored in the storage device 212 into the memory 214 and executing the program. The memory 214 includes, for example, a random access memory (RAM) and/or a read-only memory (ROM). The storage device 212 includes a tape drive, a floppy drive, a hard disk drive, or a compact disk drive. The input unit 208 includes, for example, a keyboard, a mouse, a trackball, a touch panel, a microphone, or the like that receives data input. The display unit 210 includes, for example, a display or a speaker that outputs data.

The baseband unit 204 may include a demodulation unit 218, a modulation/demodulation unit 220, an OFDM demodulation unit 222, and a modulation/demodulation unit 224 according to the purpose. Similarly, the RF unit can also include a reception unit 226, a transmission/reception unit 228, a tuner 230, and a transmission/reception unit 232 depending on the purpose.

For example, the transceiver unit 232 and the modem unit 224 can be used to perform voice communication via a wideband CDMA (WCDMA) network or a global system for mobile communication (GSM) network. The modulation/demodulation unit 224 can use a scheme such as BPSK, QPSK, 8-value PSK, 16-value QAM, or 32-value QAM as a primary modulation scheme. The modulation/demodulation unit 224 multiplies the signal subjected to the primary modulation by the PN code or the Gold code, which is assigned to each user terminal 118-i and has a small cross-correlation, or the Walsh-Hadamard code that is orthogonal to each other, thereby performing spread spectrum The signal that has been transmitted is transmitted to the transmitting/receiving unit 232. The transmission/reception unit 232 performs analog-digital (A/D) conversion on the received spread spectrum signal, amplifies it with an amplifier, and then transmits it from an antenna. In the reception operation, the transmission/reception unit 232 performs analog-digital (A/D) conversion on the received signal, and the modulation/demodulation unit 224 multiplies the synchronized code sequence again to perform despreading to restore the original signal. The modulation/demodulation unit 224 performs filtering processing on the despread wideband signal by a low pass filter (LPF) in order to remove the interference signal in the narrow band.

The tuner 230 and the OFDM demodulator 222 can also be used to receive a video stream from the content provider 114. The tuner 230 is configured to be able to change the reception band. The tuner 230 can move the reception band by receiving the instruction of the center frequency from the CPU 216 and moving the center frequency based on the instruction of the center frequency. The tuner 230 can be configured by using an all digital phase locked loop (ADPLL). The ADPLL may be configured using an adder circuit and a time-to-digital converter (TDC) circuit for converting the delay difference into a digital value for phase comparison. The ADPLL may include a Digitally Controlled Oscillator (DCO) that controls the oscillation frequency with a digital value, which enables process portability, scalability, low voltage operation, and affects output signal phase noise. The noise source can also be limited. The ADPLL may shorten the convergence time by digitally switching the loop gain of the system at the time of tuning, and may use the fractional method having the MASH Δ-Σ configuration at the time of fine adjustment and convergence of the output frequency. The tuner 230 sends the frequency-selected reception signal to the OFDM demodulation unit 222.

The OFDM demodulation unit 222 may be configured as shown in the lower part of FIG. 9, for example. The OFDM modulation method is a modulation method in which a plurality of subcarriers are used for one subband and each subcarrier is digitally modulated with different data to perform parallel transmission. The OFDM demodulation unit 222 filters the signal received by the antenna 1020 using a bandpass filter (BPF) 1022. The OFDM demodulation unit 222 converts a carrier band signal into a base band signal. Specifically, OFDM demodulation section 222, by multiplying cos (2πf _c t) to the received signal, obtains the phase component, performs filtering using a low-pass filter (LPF) 1024. Similarly, OFDM demodulation section 222, by multiplying -sin (2πf _c t) to the received signal, obtains the quadrature component, performs filtering using LPF1024. The OFDM demodulation unit 222 samples (A/D-converts) the in-phase component and the quadrature-phase component, respectively (1026), and converts the A/D-converted signal into a serial-to-parallel converter (S/P). )) 1028 divides into a plurality of data series. The transmission rate of the data sequence after S/P output is lower than the transmission rate of the received signal.

The OFDM demodulation unit 222 removes the guard interval during S/P conversion (1030). As the guard interval (cyclic prefix), a copy of the latter half of the baseband OFDM symbol is usually used by connecting it to the beginning. The addition of the guard interval makes it possible to effectively eliminate the influence of inter-symbol interference under the condition that the spread of multipath delay is less than the guard interval length.

The OFDM demodulation unit 222 performs a discrete Fourier transform (DFT) process on the signal with the guard interval removed (1032). A symbol obtained by performing a fast Fourier transform (FFT) on a received symbol sequence includes only a transmission path characteristic and a noise component corresponding to a carrier frequency that transmits the symbol, and does not include any influence from other symbols. The OFDM demodulation unit 222 performs an equalization process (1034) for correcting the influence of the transmission path characteristic in order to correctly determine a symbol, and a parallel-to-serial converter is applied to the equivalent process. (P/S)) 1036 performs P/S conversion to obtain the transmitted original digital data series. As the equalization process, minimum mean square error (MMSE) equalization may be used.

The OFDM demodulation unit 222 first demodulates the P/S converted symbol sequence (1038) and extracts a baseband signal. The OFDM demodulation unit 222 performs trellis decoding processing on the extracted baseband signal (1040). When applying the OFDM modulation method to the distribution of a video stream, it is necessary to use 16-QAM or other multilevel modulation as the modulation method for each carrier of OFDM in order to obtain a sufficient bit rate within a certain transmission bandwidth. There are often In this case, if the bit rate is increased with the bandwidth kept constant, the bit error rate characteristic deteriorates. As a means for minimizing this deterioration, each carrier of OFDM is trellis coded modulation (TCM). You may. Trellis decoding can be performed by a soft decision Viterbi algorithm. The OFDM demodulation unit 222 performs bit determination using the trellis-decoded one, and obtains a bit error rate (1042).

(3) Content Delivery Server FIG. 4 is a diagram showing the hardware configuration of the content delivery server 122.

The content distribution server 400 includes a CPU 402, a memory 404, a storage device 406, an input unit 408, an output unit 410, a transmission/reception interface (I/F) 412, a content search unit 414, and a search information generation unit 416. A search log generation unit 418, a browsing log generation unit 420, a stream segmenter 422, and a media encoder 424 are included. The storage device 406 may be a hard disk drive, a solid state drive, a flash memory, or the like that stores various data and programs. The CPU 402 realizes various functions by reading a program stored in the storage device 406 into the memory 404 and executing the program. The transmission/reception interface 412 is an interface for connecting to the core network 102, and is an adapter for connecting to Ethernet (registered trademark), a modem for connecting to a public telephone line network, or the like. The input unit 408 may be a keyboard, a mouse, a trackball, a touch panel, a microphone, or the like that receives data input. The output unit 410 may be a display, a printer, a speaker, or the like that outputs data.

The transmission/reception I/F 412 may be configured using, for example, the OFDM modulation/demodulation unit shown in FIG. 11. The reception operation of the transmission/reception I/F 412 is the same as the operation of the OFDM demodulation unit 222 of the user terminal 118-i.

The transmission/reception I/F 412 receives the video stream data from the database server 124 (1002), and performs trellis encoding processing on the symbol sequence of the received video stream data (1004). The transmission/reception I/F 412 performs primary modulation on the trellis-encoded symbol series, and digitally modulates the data represented by the symbol series. The transmission/reception I/F 412 divides the digitally modulated symbol sequence into a plurality of data sequences by the S/P converter 1008. The transmission rate of the data sequence after S/P output is lower than the transmission rate of the original video stream. The transmission/reception I/F 412 performs inverse discrete Fourier transform (IDFT) processing on the data sequence after S/P output (1010). The transmission/reception I/F 412 performs P/S conversion by the P/S converter 1012 on the symbol sequence subjected to the inverse fast Fourier transform (IFFT), and obtains a transmission digital data sequence. The transmission/reception I/F 412 performs serialization (D/A conversion) on the transmission digital data sequence (1016). Receiving I / F 412 is, by multiplying cos (2πf _c t) to transmit digital data sequence to obtain the in-phase component, by multiplying -sin (2πf _c t) to transmit digital data sequence to obtain the quadrature component. The transmission/reception I/F 412 amplifies the obtained in-phase component and quadrature-phase component by the amplifier 1018 and sends the amplified component through the antenna 1020.

The content search unit 414 searches the database server 124 for the content specified by the selection signal from the user terminal 118-i. The search information generation unit 416 generates the information of the sequence of the content searched in response to the selection signal from the user terminal 118-i in the form associated with the “user id” i, and searches for the searched content. The sequence information is sent to the search log generator 418. The search log generation unit 418 adds a search date and time to the information regarding the searched content sequence to generate a search log. The search log generation unit 418 sends to the browse log generation unit 420 a search log in which the date and time of the search is added to the information regarding the searched content sequence. The browsing log generation unit 420 determines whether the search by the selection signal from the user terminal 118-i corresponds to browsing, or whether it corresponds to mere search, based on the time when the user i actually viewed the content. To do. There is a case where the user i sends a selection signal from the user terminal 118-i in the process of zapping the program and the content is recorded in the search log, while the user i browses the program for a certain time or more. This is because it may be viewed for the purpose. The browsing log generation unit 420 outputs, as a browsing log, a search log sent from the search log generation unit 418 that corresponds to browsing by the search by the selection signal from the user terminal 118-i.

The media encoder 424 receives the real-time video stream signal from the database server 124 and encodes and encapsulates the received real-time video stream signal for distribution. The encoding is H.264. In a format receivable by the user terminal 118-i, such as H.264 video and HE-AAC audio. The receivable delivery format is an MPEG-2 transport stream. The media encoder 424 transmits the real-time video stream packet encoded by the MPEG-2 transport stream to the stream segmenter 422 via the LAN. The stream segmenter 422 receives the H.264 stream based on the input from the media encoder 424. Generate a plurality of video stream segment files consisting of a plurality of transport stream (ts) files containing a plurality of segments of an MPEG-2 transport stream carrying a H.264 video stream.

(4) Database Server FIG. 5 is a diagram showing a hardware configuration of the database server 124.

The database server 500 includes a content search information database 502, a user browsing log database 504, a user search log database 506, a user personal information database 508, a content database 510, a fragment-pointer correspondence table 512, and an SNS service provider address. A database 514 and a user posting history database 516 are included. The content search information database 502, the user browsing log database 504, the user search log database 506, and the user personal information database 508 form a user information area indexed by “user id” i, and a content database 510, The fragment-pointer correspondence table 512 forms a content area indexed by “content id” l, and the SNS service provider address database 514 and the user posting history database 516 form an SNS service provider information area.

The content search information database 502 stores the information about the sequence of the content searched by the search information generation unit 416 in response to the selection signal from the user terminal 118-i. Information about the retrieved sequence of content is stored in association with the "user id" i. The user search log database 506 stores the search log generated by the search log generation unit 418 by adding the search date and time to the information regarding the sequence of the searched content. The search log is stored in a form associated with the "user id" i. The user browsing log database 504 stores a browsing log generated by the browsing log generation unit 420 by extracting a search log that corresponds to browsing by a search by a selection signal from the user terminal 118-i. The user personal information database 508 stores, for each “user id” i, personal information of the user i, that is, the sex, age, address, occupation, used terminal, presence/absence of credit, point balance, and e-mail of the user i. Stores the presence or absence, etc.

The content database 510 stores content in units of video stream fragments obtained by dividing the real-time video stream into arbitrary lengths for each “content id” 1. Each video stream fragment is composed of encoded data for each fragment and a header attached to each encoded data. The real-time video stream may be distributed in video stream fragment units. The fragment-pointer correspondence table 512 stores a correspondence relationship between each video stream fragment and a pointer designating a storage location of the fragment in the content database 510.

The SNS service provider address database 514 stores the address information for each SNS service provider 116. The user posting history database 516 stores a series of video stream fragments posted by the user i in association with the “user id” i.

(5) SNS Server, Database Server, and Web Server FIG. 6 is a diagram showing the hardware configuration of the SNS server 128.

The SNS server 600 includes a CPU 602, a memory 604, a storage device 606, an input unit 608, an output unit 610, a transmission/reception interface (I/F) 612, a video stream fragment reception unit 614, and a message reception unit 616. , Message posting section 618 and video stream fragment posting section 620. The CPU 602, the memory 604, the storage device 606, the input unit 608, the output unit 610, and the transmission/reception interface (I/F) 612 are the same as those of the content distribution server 122.

The video stream fragment receiving unit 614 receives the video stream fragment posted on the SNS site such as Twitter (trademark) from the content provider 114 or the user terminal 118-i. The video stream fragment receiving unit 614 can cooperate with the content provider 114, and when the user terminal 118-i transmits a video stream fragment posting request to the SNS service provider 116 via the content provider 114, the content provider 114-i Video stream fragments posted from 114 may be received. Further, when the user terminal 118-i downloads the video stream fragment from the content provider 114 and then uploads it, the video stream fragment receiving unit 614 receives the video stream fragment posted from the user terminal 118-i. May be. The message receiving unit 616 receives the posted message from the user terminal 118-i. The message publishing unit 618 publishes the received message on the SNS site. The video stream fragment posting unit 620 posts the posted video stream fragment on the SNS site.

FIG. 7 is a diagram showing a hardware configuration of the database server 130.

The database server 700 includes a message posting history database 702, a video stream fragment posting history database 704, a user personal information database 706, a message database 708, a video stream fragment database 710, a content provider address database 712, and a user posting history. And a database 714. The message posting history database 702, the video stream fragment posting history database 704, and the user personal information database 706 form a user information area indexed by “user id” i, and the message database 708 and the video stream fragment database 710 are , SNS areas are formed, and the content provider address database 712 and the user posting history database 714 form a content provider information area.

The message posting history database 702 stores, for each “user id” i, a sequence of messages posted by the user i to the SNS service provider 116 with the date and time of posting. The video stream fragment posting history database 704 stores, for each “user id” i, a sequence of video stream fragments posted by the user i to the SNS service provider 116 with the date and time of posting. The user personal information database 706 stores, for each “user id” i, the sex, age, address, occupation, used terminal, presence/absence of credit, point balance, presence/absence of e-mail transmission, etc. of the user i.

Message database 708 stores messages posted and posted on SNS sites, and video stream fragment database 710 stores video stream fragments posted and posted on SNS sites. The content provider address database 712 stores the address information for each content provider 114. The user posting history database 714 is, for each content identified by the “content id” 1 and for each posted message, the sequence of the “user id” that posted the content, and the “user id” that posted the message. Stores the sequence of.

FIG. 8 is a diagram showing the hardware configuration of the Web servers 120 and 126.

The web server 400 includes a CPU 402, a memory 404, a storage device 406, an input unit 408, a transmission/reception interface 410, and an output unit 412. The CPU 602, the memory 604, the storage device 606, the input unit 608, the output unit 610, and the transmission/reception interface (I/F) 612 are the same as those of the content distribution server 122.

(6) Delivery of Real-Time Video Stream FIG. 10 is a diagram showing how the real-time video stream is stored in the content database 510 of the database server 124.

The content database 510 stores content in units of video stream fragments obtained by dividing the real-time video stream into arbitrary lengths for each “content id” 1. This storage method makes it easy to post a video stream fragment at an arbitrary position of the real-time video stream to the SNS site while viewing the real-time video stream on the user terminal 118-i using only the user terminal 118-i. Enable by the way. Each video stream fragment is composed of encoded data for each fragment, a header attached to each encoded data, and a prefix portion indicating a unique type of the file.

The prefix portion 902 may be assigned a unique type including, for example, four alphabetic characters, depending on the type of data to be stored. The header portion 904 stores the frame size of encoded data, the length of reproduction time, address information indicating the storage position of encoded data, and header information such as decoding and display time. Here, for example, if only one header part is provided in one real-time video stream segment, the header information is stored in that one header part, so that the header is proportional to the playback time length of the real-time video stream. The size of the part increases. As a result, even in the case of playing while downloading, such as progressive download, it is necessary to acquire the header portion before starting playback, which causes a problem that the waiting time until the playing time becomes long. Therefore, in the present embodiment, the header portion 904 is provided for each video stream fragment.

The encoded data is stored in the decoding order, in which audio frames and video frames are alternated in frame units. At the time of reproduction, the encoded data is acquired as frame data based on the address by specifying the storage address of the frame corresponding to the desired reproduction time by referring to the header part.

FIG. 11 is a diagram showing distribution of a real-time video stream according to the RTP (Real Time Transport) protocol.

The RTP protocol is a protocol for packetizing real-time data such as video and audio and transmitting it on an IP network. In streaming according to the RTP protocol, the user terminal 118-i receives the content stored in the content distribution server 122 in the following procedure. That is,
Step 1. Address information of the content distribution server 122 for acquiring encoded data of video and audio is acquired.

Step 2. A session is established between the user terminal 118-i and the content distribution server 122.

Step 3. An RTP packet storing encoded data of video and audio is received.

As a protocol for controlling communication between the content distribution server and the user terminal 118-i, RTSP (Real Time Streaming Protocol) can be used, for example, and playback control such as playback start, end, and pause can be performed. , RTSP can be executed as a command. A communication channel different from RTP can be used for transmitting and receiving RTSP data, and a highly reliable transfer control protocol (Transmission Control Protocol (TCP)) can be used for a lower layer.

FIG. 12 is a diagram showing the data structure of the RTP packet.

The RTP header portion 1202 is a counter for RTP packets, which is a value indicating the identification information and reproduction time of encoded video data and encoded voice data stored in the RTP payload 1204, and the type of the real-time video stream to be transmitted. It includes a sequence number and a time stamp that is the sampling time of the first byte of the payload data. The RTP payload portion 1204 is composed of a payload header 1206 and payload data 1208, the payload header 1206 includes header information specific to an encoding method, and the payload data 1208 stores encoded data. The payload format, which is the data storage method in the payload portion 1208, is H.264. A format for each encoding method such as H.264 or AAC (Advanced Audio Coding) can be adopted.

FIG. 13 is a diagram showing HTTP Live Streaming (HLS) protocol streaming.

The HTTP Live Streaming protocol streaming requires that the content distribution server 122 encodes and divides a moving image file to be distributed, and at the same time creates a playlist file indicating in which order the files should be reproduced. The media encoder 424 of the content distribution server 122 sends the video to be distributed in the H.264 format. The file is encoded into H.264/AAC format and converted into an MPEG2-TS format file, and the stream segmenter 422 divides the file every designated seconds, and at the same time generates an index file including a playlist. The user terminal 118-i can reproduce the moving image by sequentially downloading the divided files by HTTP according to the index file including the playlist.

The media encoder 424 receives the real-time video stream signal from the database server 124 and encodes and encapsulates the received real-time video stream signal for distribution. The encoding is H.264. In a format receivable by the user terminal 118-i, such as H.264 video and HE-AAC audio. The receivable delivery format is an MPEG-2 transport stream. The media encoder 424 does not change the setting of the real-time video stream such as the size of the video data or the codec type during the encoding of the real-time video stream. The media encoder 424 changes the setting of the real-time video stream at the boundary of the segment and sets a predetermined tag on the subsequent segment. The media encoder 424 transmits the real-time video stream packet encoded by the MPEG-2 transport stream to the stream segmenter 422 via the LAN. The stream segmenter 422 receives the H.264 stream based on the input from the media encoder 424. Generate a plurality of video stream segment files consisting of a plurality of transport stream (ts) files containing a plurality of segments of an MPEG-2 transport stream carrying a H.264 video stream. The stream segmenter 422 generates an index file (M3U8) including a playlist of a plurality of media files. The index file is used to obtain information and location regarding the availability of these multiple media files.

In HTTP Live Streaming, moving pictures with different bandwidths (symbol rates) such as “Low Quality”, “Middle Quality”, and “High Quality” shown in FIG. 13 are prepared, and the information is described in an index file. be able to. This enables the user terminal 118-i that reproduces a moving image to switch to a moving image having a different bandwidth according to its own environment.

FIG. 14 is a sequence diagram showing establishment of a session between the user terminal 118-i and the content distribution server 122.

The NodeB 110 and the eNodeB 112 transmit a synchronization signal used for cell search by the user terminal 118-i via SCH (Synchronization Channel). The user terminal 118-i searches and acquires the SCH for synchronization (step S1402). Upon supplementing the SCH, the user terminal 118-i establishes synchronization and acquires the cell id. The NodeB 110 and the eNodeB 112 include minimum information such as the system bandwidth, the system frame number, and the number of transmitting antennas that the user terminal 118-i should read first after the cell search via the PBCH (Physical Broadcast Channel). Sending a signal. The user terminal 118-i acquires information specific to the NodeB 110 or the eNodeB 112 such as the system bandwidth, the system frame number, and the number of transmitting antennas by supplementing the P-BCH (Primary Broadcast Channel) (step S1404). .. The user terminal 118-i acquires information about PRACH (Physical Random Access Channel) by supplementing D-BCH (Dynamic Broadcast Channel), and specifies the frequency position of PRACH (step S1406). The user terminal 118-i transmits the RACH preamble to the NodeB 110 or the eNodeB 112 based on the uplink frequency band and the frequency position of the PRACH obtained in step S1406 (step S1408).

The NodeB 110 or the eNodeB 112 receives the RACH preamble from the user terminal 118-i and performs adaptive bit allocation processing (step S1410). Based on the communication channel conditions estimated from the RACH preamble symbols, the NodeB 110 or eNodeB 112 initiates an adaptive allocation procedure for allocating appropriate frequency slots and bits for all user terminals 118-i, and allocates system channel capacity. maximize. j (j=1,..., N _c ) is a subcarrier number, m (m=1,..., N _m ) is a number indicating the type of modulation scheme, and H(i,j) is a preamble symbol based on the preamble symbol. Assuming the communication channel frequency response is estimated using the uplink RACH preamble symbols structured with pilot tones, the carrier-to-noise power ratio for user terminal 118-i on subcarrier j under multipath fading environment ( CNR) is
It can be estimated that Here, the variable m is, for example, m=1 when the modulation scheme is BPSK, m=2 when the modulation scheme is QPSK, and m=3, 16-value QAM when the modulation scheme is 8-ary PSK. In the case of m=4 and 32-value QAM, m=5 and in the case of 128-value QAM, m=7, indicating the number of bits that can be transmitted in one symbol.

If Q() is the error complementary function, the estimated carrier-to-noise power ratio R ^(CNR) (i,j,m) is used to user terminal 118 on subcarrier j when using the m-bit modulation scheme. The predicted value E ^(BER) (i, j, m) of the bit error rate (BER) characteristic for −i is
Becomes here,
Is.

s (s=1,..., N _s ) is the frequency slot number, N _s is the number of available frequency slots in the allocated frequency band, and N _c /N _s is the number of subcarriers included in one frequency slot. , The subcarrier j _max having the worst BER characteristic in the target slot s is
And the worst BER characteristic B ^(BER) (i, s, m) for frequency slot s is
Becomes If N _p is the number of bytes in one packet, the predicted value E ^(PER) (i,m ⁾ of the packet error rate (PER) characteristic when the m-bit modulation scheme is assigned to the user terminal 118-i in the slot s. , S) is
Becomes A target PER characteristic commonly required in the system is E ^(PER) _0, and the maximum m that satisfies the condition E ^(PER) (i,s,m)≦E ^(PER) ₀ in the frequency slot s is set for each user terminal. For 118-i,
And M _i,s becomes a matrix of N _u ×N _s .

By summing the number of assignable bits over all frequency slots, the overall communication channel condition V _i for each user terminal 118- _i is
Is asked. V _i becomes a matrix of N _u ×1. For each element of the matrix M _i,s, a matrix in which the corresponding element is 0 when the element is 0 and the corresponding element is 1 when the element is an integer other than 0 is defined as A _i,s To do. For example, if the bit that can be allocated to the user terminal 118-i in the frequency slot s is 0, that is, the target PER commonly required in the system regardless of which modulation scheme the user terminal 118-i uses. When the user terminal 118-i cannot use the frequency slot s by not satisfying the characteristic E ^(PER) _{0 ,} the i,s component of the matrix A _i,s becomes 0. On the other hand, when the number of bits that can be assigned to the user terminal 118-i in the frequency slot s is m _, the i,s component of the matrix A _i,s becomes 1. Due to the number of user terminals 118-i that can utilize frequency slot s, the overall communication channel condition W _s for slot _s is
Is asked.

Suitable frequency slot and bit using the matrices V _i and W _s, assigned adaptively to each user terminal 118-i according to the following criteria. That is,
Criterion 1. User terminals 118-i with smaller values of V _i have higher priority in allocation.

Criterion 2. For a user terminal 118-i, more frequency slot having smaller values of W _s have a higher priority in the assignment.

By using the above criteria, user terminals 118-i with higher values of V _i and W _s will have lower priority, but still more flexible frequency slot allocation can be achieved. .. The reason is that the user terminal 118-i having a larger value of V _i and W _s has more opportunity in frequency slot allocation, even if the order of allocation is later. Therefore, it is possible to reduce the interruption of communication with the user terminal 118-i due to the frequency slot not being assigned.

FIG. 15 is a flowchart of the adaptive bit allocation process performed between the NodeB 110 or eNodeB 112 and the user terminal 118-i.

In step S1504, the NodeB 110 or the eNodeB 112 sets the “user id” to i=1. In step S1506, the NodeB 110 or the eNodeB 112 sets “frequency slot number” to s=1. The NodeB 110 or the eNodeB 112 sets the initial value E ^(PER) ₀ (i,s) of the packet error rate characteristic to E ^(PER) ₀ (i,s)=0 (step S1508). In step S1510, the NodeB 110 or the eNodeB 112 sets “type of modulation scheme” to m=1. The NodeB 110 or the eNodeB 112 sets the initial value E ^(BER) ₀ of the bit error rate to E ^(BER) ₀ =0. In step S1504, the NodeB 110 or the eNodeB 112 sets “subcarrier number” to j=1.

The NodeB 110 or the eNodeB 112, based on the uplink RACH preamble symbols received from the user terminal 118-i, for the user terminal 118-i on the subcarrier j for the modulation scheme type m, the carrier-to-noise power ratio R ^{( CNR)} (i, j, m) is estimated (step S1516). The NodeB 110 or the eNodeB 112 predicts the bit error rate characteristic E ^(BER) (i, j, m) using the carrier-to-noise power ratio R ^(CNR) (i, j, m) (step S1518). When the bit error rate characteristic satisfies E ^(BER) (i,j,m)>E ^(BER) ₀ , the NodeB 110 or the eNodeB 112 has E ^(BER) ₀ ←E ^(BER) (i,j,m). (It means a process of substituting the value of E ^(BER) (i, j, m) into the variable E ^(BER) _{0. The} same applies hereinafter) and the process of j _max ←j is performed (step S1520).

The NodeB 110 or the eNodeB 112 determines whether the “subcarrier number” j is smaller than s(N _c +1)/N _s (step S1522). When the “subcarrier number” j is smaller than s(N _c +1)/N _s , the NodeB 110 or the eNodeB 112 performs j←j+1 (step S1524), and the process returns to step S1516.

If the “subcarrier number” j is greater than or equal to s(N _c +1)/N _s , the NodeB 110 or eNodeB 112 uses the value of j _max and has the worst BER characteristic “B ^(BER) ” for slot s. (I, s, m)" is obtained, and the packet error rate characteristic E ^(PER) (i, s, m) is predicted (step S1526). When the packet error rate characteristic satisfies E ^(PER) ₀ (i,s)<E ^(PER) (i,s,m)≦E ^(PER) ₀ , the NodeB 110 or the eNodeB 112 outputs E ^(PER) _0. The processing of (i,s)←E ^(PER) (i,s,m) and m _max (i,s)←m is performed (step S1528). Here, E ^(PER) ₀ is a target PER characteristic commonly required in the system, and m _max (i,s) is a condition E ^(PER) (for the user terminal 118-i in the slot s. i, s, m)≦E ^(PER) ₀ is the maximum m.

The NodeB 110 or the eNodeB 112 determines whether the “modulation scheme type” m is smaller than N _m (step S1530). When the “modulation scheme type” m is smaller than N _m , the NodeB 110 or the eNodeB 112 performs the process of m←m+1 (step S1532), and the process returns to step S1512. When the type “m” of the modulation scheme is N _m or more, the NodeB 110 or the eNodeB 112 stores m _max (i,s) of each user terminal 118-i in the slot s (step S1534). , "Frequency slot number" s is smaller than N _s (step S1536). If "frequency slot number" s is smaller than N _s , the NodeB 110 or eNodeB 112 is s←s+1. (Step S1538), and the process returns to step S1508. If the frequency slot number “s” is N _s or more, the NodeB 110 or the eNodeB 112 determines whether the “user id” i is smaller than N _u . It is determined whether or not (step S1540). When "user id" i is smaller than _{N u} is the NodeB110 or eNodeB112, i ← i + 1 of the processing carried out (step S1542), the process returns to step S1506. When "user id" i is greater than or equal to _{N u} is Node B 110 or eNodeB112 the priority slot for each user terminal 118-i, and according to the priority of the bit allocation for each user terminal 118-i, the frequency slot And adaptively allocate bit m of the modulation scheme.

Returning to FIG. 14 again, the NodeB 110 or the eNodeB 112 transmits the frequency slot, modulation bit, and time slot allocation information to the user terminal 118-i (step S1412). The user terminal 118-i transmits a response to the notification of the frequency slot, the number of bits of the modulation symbol, and the allocation information of the time slot to the NodeB 110 or the eNodeB 112 (step S1414). The user terminal 118-i transmits the video stream distribution request to the NodeB 110 or the eNodeB 112 (step S1416), and the NodeB 110 or the eNodeB 112 transmits the video stream distribution request to the content distribution server 122 (step S1418). At this stage, the user terminal 118-i and the content distribution server 122 are in a data communicable state (step S1420). The content distribution server 122 transmits the program guide to the NodeB 110 or the eNodeB 112 (step S1422), and the NodeB 110 or the eNodeB 112 transmits the program guide to the user terminal 118-i (step S1424).

The program guide may be configured, for example, as shown in FIG. In the illustrated example, the horizontal direction (longitudinal direction) of the display unit 210 corresponds to each program channel, and the vertical direction corresponds to each time zone. The program guide shown in FIG. 16 can be freely scrolled in the longitudinal direction, the longitudinal direction, and the oblique direction as shown in the drawing, and can also be rotated in a circle. For example, program channels include "Abema News", "Live Sports", "Sport1", and "Sport2". Of these, "Abema News" and "Live Sports" are live, that is, live broadcasts. “Sport 1” and “Sport 2” may be live broadcast or video recording.

Thus, the decisive difference between the video stream distribution of the present embodiment and the conventional Video On-Demand stream distribution is that (1) each program (program) is distributed according to the schedule determined by the program table, (2) It is possible to watch live, that is, live broadcasting. According to the video stream distribution according to the present embodiment, it is possible to view and listen to the reserved program of the program and the reserved recording of the program by designating the program channel and the time zone by the above program guide, and the program missed in the past can be viewed. It is also possible to view by specifying in the program table.

Returning to FIG. 14 again, in response to the reception of the program guide, the user terminal 118-i transmits a selection signal indicating the program channel in which the program selected by the user i is distributed to the NodeB 110 or the eNodeB 112 (step (S1426), the NodeB 110 or the eNodeB 112 transmits the selection signal to the content distribution server 122 (step S1428). The selection signal is used when the content distribution server 122 attempts to view a program such as a live broadcast or a recorded broadcast that is distributed according to the program guide, and when the content distribution server 122 attempts to view a program already distributed (time-shift viewing). In both cases, the content is sent from the user terminal 118-i to the content distribution server 122 via the NodeB 110 or the eNodeB 112. The selection signal is used to specify a program channel to be selected when trying to watch a program that is currently distributed or will be distributed in the future, and in the case of so-called time-shifted viewing, the selection signal is specified. Used to do. The content distribution server 122 that has received the selection signal performs a symbol rate (bandwidth) negotiation with the user terminal 118-i (step S1430).

The bandwidth negotiation performed between the content distribution server 122 and the user terminal 118-i is performed by a hierarchical QoS (Quality of Service) control function in the case of distribution of a real-time video stream according to the RTP protocol, for example. Be seen.

FIG. 17 is a diagram showing the configuration of the hierarchical QoS control function according to the RTP protocol.

The content database 510 of the database server 124 stores, for example, content encoded at a plurality of encoding rates of F ₁ [Gbps], F ₁ [Gbps], F ₃ [Gbps],... When the transfer rate is adjusted by bandwidth control between the server 122 and the user terminal 118-i, the data amount is adjusted by selecting the content. The content distribution server 122 stores an MVX file describing content information and server information, and selects an optimum content by a bandwidth negotiation function when a session between the user terminal 118-i and the content distribution server 122 is established. .. The MVX file describing the content information and the server information describes the number of media data held by the content and the bandwidth information. The congestion prediction and detection function, transfer rate control function, and limited retransmission function are the same as in the frame thinning-type video distribution system, but when the congestion prediction and detection function raises or lowers the bandwidth, hierarchical contents The contents are switched by the selection function.

The bandwidth negotiation function is a system band that can be received from the state of the mobile communication network 104 to which the user terminal 118-i is connected when the user terminal 118-i establishes an initial session with the content distribution server 122. This is a function of recognizing the width and notifying the content distribution server 122. The bandwidth negotiation function according to the RTP protocol performs session management by RTSP and RTCP, and uses RTSP and RTCP to perform bandwidth negotiation when an initial session is established. The content distribution server 122 selects and distributes the optimum content for the band notified from the plurality of hierarchical contents held as the content.

Since the transfer rate control function of the frame thinning-out type QoS control is a method of thinning out moving image frames by using the frame rate control function, the frame rate tends to be extremely reduced at the time of congestion, such as continuous still screens. In some cases, the playback quality was reduced due to video playback. On the other hand, in the hierarchical QoS control, a hierarchical content selection function is added as one function of the transfer rate control function, and the dynamically predictable bandwidth can be estimated by the congestion prediction and detection function. The content selection function controls the transfer rate by dynamically switching to the optimum content based on this bandwidth. The transfer rate control of such a hierarchical QoS control method does not control the band by adjusting only the frame rate unlike the frame thinning-out type QoS control, so that a freeze time occurs on the reproducing side even during congestion. Hard and smooth playback can be achieved.

FIG. 18 is a diagram showing the configuration of the QoS control function according to the HTTP Live Streaming (HLS) protocol.

In the reproduction of HTTP Live Streaming, the user terminal 118-i reads the playlist of the index file (M3U8), accesses a plurality of divided media files in the order shown in the playlist, and performs reproduction. First, read the first index file, then access the URL of the media file listed in the index file to play it, and then access the URL of the media file listed next to play it. Are played in sequence. Finally, the index file is read again and the reproduction ends. Therefore, in normal streaming reproduction, once the connection is established, the connection is not disconnected until the reproduction is completed, but in the reproduction of HTTP Live Streaming, the connection establishment and disconnection are repeated each time a different file is accessed.

In reproducing HTTP Live Streaming, moving pictures with different bandwidths (symbol rates) such as “Low Quality”, “Middle Quality”, and “High Quality” shown in FIG. 13 are prepared, and the information is stored in the index file. Can be described. This enables the user terminal 118-i that reproduces a moving image to switch to a moving image having a different bandwidth according to its own environment. For example, when the environment of the mobile communication network 104 that handles the user terminal 118-i deteriorates, it is possible to switch to a moving image with a lower bandwidth than the present. Further, in addition to information on different bandwidths, when there are a plurality of content distribution servers 122 that distribute video, that information can be described in the indexable file. This means that, even if the video stream cannot be played back due to a failure of any of the content distribution servers 122, the user terminal 118-i will not be able to use another content described in the index file. By accessing the distribution server 122, it is possible to reproduce the moving image.

In addition to the RTP protocol and the HLS protocol, QoS control according to MPEG-DASH (Dynamic Adaptive Streaming over HTTP) may be performed. In the delivery of real-time video stream in accordance with MPEG-DASH, variations in watch videos in a variety of user terminals 118-i, considering the user's environment bandwidth such, the symbol rate so that reproduction is not interrupted By doing so, the moving image can be viewed with the optimum quality for the system band. For example, if the mobile communication network 104 is congested and the bandwidth is narrow, the reproduction may be interrupted if the moving image is delivered at a high bit rate. Therefore, the bit rate is changed to the optimum one. Make sure playback is not interrupted.

In order to switch the bit rates, media files corresponding to a plurality of bit rates are prepared in advance in the database server 124 of the content provider 114, and information about them is described in an MPD (Media Presentation Description) file. .. The user terminal 118-i first acquires the MPD file and executes the analysis. Information necessary for streaming distribution such as program timing, acquisition destination of media file, maximum bit rate and minimum bit rate is acquired by analysis, and a video stream segment is acquired using an HTTP GET request to start streaming. After a certain amount of buffering is performed, the system bandwidth is also monitored, and this measurement determines the bit rate to maintain and secure a sufficient buffer amount.

FIG. 19 is a sequence diagram of a symbol rate (bandwidth) negotiation performed between the content distribution server 122 and the user terminal 118-i.

The user terminal 118-i that has received the program guide from the content distribution server 122 transmits a selection signal to the content distribution server 122 via the NodeB 110 or the eNodeB 112 (steps S1912, S1914). Upon receiving the selection signal, the content distribution server 122 transmits the real-time video stream having the lowest symbol rate F ₁ of the program (program) to the NodeB 110 or the eNodeB 112 (step S1916), and the NodeB 110 or the eNodeB 112 sends it to the user terminal 118-i. The real-time video stream is transmitted (step S1918). The user terminal 118-i demodulates and decodes the received real-time video stream with the lowest symbol rate F ₁ to estimate the bit error rate (step S1920). The user terminal 118-i determines whether to increase the received symbol rate F ₁ based on the estimated bit error rate (step S1922). At this time, when the estimated bit error rate is extremely low and it is difficult to estimate the signal power to noise power ratio (SNR), the user terminal 118-i increases the transmission symbol rate and decreases the modulation index. Request to the content distribution server 122 for transmission. The user terminal 118-i transmits a symbol rate increase request signal to the NodeB 110 or the eNodeB 112 (step S1924), and the NodeB 110 or eNodeB 112 transmits the symbol rate increase request signal to the content distribution server 122 (step S1926). The content distribution server 122, which has received the symbol rate increase request signal, transmits the real-time video stream having the next lowest symbol rate F ₂ of the program to the NodeB 110 or the eNodeB 112 (step S1928), and the NodeB 110 or eNodeB 112 sends the user terminal 118-i. The real-time video stream is transmitted to (step S1930). By repeating this procedure, the highest symbol rate receivable under the current environment of the mobile communication network in which the user terminal 118-i is handled is determined.

Returning to FIG. 14 again, when the highest symbol rate receivable under the current environment of the mobile communication network in which the user terminal 118-i is handled is determined, the content distribution server 122 makes the determination. The distribution of the real-time video stream of the program selected at the selected symbol rate is started (step S1432).

(7) Zapping Operation During Program Viewing FIG. 20 is a flowchart of the zapping operation during program viewing on the user terminal 118-i. 21 and 22 are diagrams showing a state of lateral (longitudinal) zapping on the display unit 210 of the user terminal 118-i. FIG. 23 is a diagram showing a state of vertical zapping on the display unit 210 of the user terminal 118-i.

As shown in the upper diagram of FIG. 21, in the lateral zapping operation, a session between the user terminal 118-i and the content distribution server 122 is established, and the real-time video stream of the selected program channel is displayed. After the start of reception, the selected main program channel is displayed in the central part, and two adjacent program channels of the main program channel are displayed in the left and right parts of the main program channel. In this state, the selected main program channel is being received and reproduced at a high symbol rate, and the two adjacent program channels are being received and reproduced at a symbol rate lower than the symbol rate of the main program channel. The two adjacent program channels appear smaller than the main program channel. Similarly, in the left diagram of FIG. 23, the selected main program channel is displayed in the central portion, and two adjacent program channels of the main program channel are displayed in the upper and lower portions of the main program channel. Similarly, the selected main program channel is received and regenerated at a higher symbol rate and the two adjacent program channels are received and regenerated at a symbol rate lower than the symbol rate of the main program channel. The two adjacent program channels appear smaller than the main program channel.

When the user i attempts to move the display position of the main program channel with one finger in one direction as shown in the figure, the user terminal 118-i moves the display position of the main program channel to the input unit 208. It is detected as an input by the user i (step S2004). The CPU 216 of the user terminal 118-i monitors the amount of movement of the display position of the main program channel (step S2006). The CPU 216 of the user terminal 118-i determines whether or not the movement amount of the display position of the main program channel has become equal to or larger than the first threshold value x ₁ (step S2008). When the movement amount of the display position of the main program channel is not equal to or larger than the first threshold value x ₁ , the process returns to step S2006, and the CPU 216 of the user terminal 118-i moves the display position of the main program channel. Continue volume monitoring. When the amount of movement of the display position of the main program channel is equal to or larger than the first threshold value x ₁ , the CPU 216 of the user terminal 118-i receives and reproduces the adjacent program channel in one direction which is the movement direction. It ends (step S2010). The state at this point is shown in the lower diagram of FIG. 21 and the central diagram of FIG.

After receiving and reproducing the adjacent program channel in one direction, the CPU 216 of the user terminal 118-i monitors the movement amount of the display position of the main program channel (step S2012). The CPU 216 of the user terminal 118-i determines whether or not the movement amount of the display position of the main program channel has become equal to or larger than the second threshold value x ₂ (step S2014). When the amount of movement of the display position of the main program channel is not greater than or equal to the second threshold value x ₂ , the CPU 216 of the user terminal 118-i again sets the amount of movement of the display position of the main program channel to the first threshold value. determines whether or not x ₁ or more (step S2016). If the amount of movement of the display position of the main program channel is greater than or equal to the first threshold value x ₁ (x ₁ ≤ (the amount of movement of the display position of the main program channel) <x ₂ ), the process returns to step S2012, The CPU 216 of the user terminal 118-i continues to monitor the movement amount of the display position of the main program channel after the reception and reproduction of the adjacent program channel in one direction, which is the first movement direction, is completed. When the amount of movement of the display position of the main program channel becomes smaller than the first threshold value x ₁ ((the amount of movement of the display position of the main program channel)<x ₁ ), the CPU 216 of the user terminal 118-i , The reception and reproduction of the adjacent program channel in one direction which is the first movement direction are restarted (step S2018), the process returns to step S2006, and the CPU 216 of the user terminal 118-i causes the display position of the main program channel. Will continue to monitor the amount of movement. In this state, the user i temporarily moves the display position of the main program channel beyond the first threshold value x ₁ , but thereafter, the movement amount of the display position of the main program channel is set to be smaller than the first threshold value x ₁ . It means that it has been returned to a smaller size.

In step S2014, when the amount of movement of the display position of the main program channel is equal to or larger than the second threshold value x ₂ , the adjacent program channel in the other direction opposite to the one direction which is the first movement direction is further increased. Reception and reproduction of the adjacent adjacent program channel are started (step S2020). The state at this point is shown in the lower diagram of FIG. 22 and the right diagram of FIG. 23. After starting reception and reproduction of the adjacent program channel further adjacent to the adjacent program channel in the other direction opposite to the one direction, the CPU 216 of the user terminal 118-i monitors the movement amount of the display position of the main program channel. Yes (step S2022). The CPU 216 of the user terminal 118-i determines whether or not the adjacent program channel in the other direction opposite to the one direction which is the first moving direction has reached the initial position (central portion) of the main program channel. Yes (step S2024). When the adjacent program channel in the opposite direction to the one direction reaches the initial position (central portion) of the main program channel, the CPU 216 of the user terminal 118-i is the first moving direction. The adjacent program channel in the opposite direction to the one direction is received and played at a high symbol rate to create a precise video, and the original main program channel is received and played at a low symbol rate to create a rough video. It is displayed (step S2028). In this state, it means that the adjacent program channel in the other direction opposite to the one direction that is the first movement direction has become the main program channel, and the CPU 216 of the user terminal 118-i determines that the adjacent program channel is the main program channel. A selection signal designating a program channel is generated and transmitted to the content distribution server 122. The search log generation unit 418 of the content distribution server 122 generates a search log and sends the search log to the database server 124, and the database server 124 stores the search log in the user search log database 506.

In step S2024, if the adjacent program channel in the other direction opposite to the one direction that is the first movement direction has not reached the initial position (center portion) of the main program channel, the user terminal 118-i. The CPU 216 determines whether the amount of movement of the display position of the main program channel is equal to or greater than the second threshold value x ₂ (step S2026). When the movement amount of the display position of the main program channel is equal to or larger than the second threshold value x ₂ , the process returns to step S2022, and the CPU 216 of the user terminal 118-i determines the movement amount of the display position of the main program channel. Continue monitoring. If the amount of movement of the display position of the main program channel becomes smaller than the second threshold value x _{2 in} step S2026, the process returns to step S2016, and the CPU 216 of the user terminal 118-i again sets the main program again. It is determined whether or not the amount of movement of the display position of the channel is greater than or equal to the first threshold value x ₁ .

If the amount of movement of the display position of the main program channel is greater than or equal to the first threshold value x ₁ (x ₁ ≤ (the amount of movement of the display position of the main program channel) <x ₂ ), the process returns to step S2012, The CPU 216 of the user terminal 118-i continues to monitor the amount of movement of the display position of the main program channel after the reception and reproduction of the adjacent program channel in one direction are completed. In this state, the user i once moves the display position of the main program channel beyond the second threshold value x ₂ , but thereafter, the movement amount of the display position of the main program channel is set to the second threshold value x _{2 or} more. It means that it has been returned to a smaller size.

When the amount of movement of the display position of the main program channel becomes smaller than the first threshold value x ₁ ((the amount of movement of the display position of the main program channel)<x ₁ ), the CPU 216 of the user terminal 118-i , The reception and reproduction of the adjacent program channel in one direction which is the first movement direction are restarted (step S2018), the process returns to step S2006, and the CPU 216 of the user terminal 118-i causes the display position of the main program channel. Will continue to monitor the amount of movement. In this state, the user i temporarily moves the display position of the main program channel beyond the second threshold value x ₂ , but thereafter, the movement amount of the display position of the main program channel is set to be smaller than the first threshold value x ₁ . It means that it has been returned to a smaller size.

(8) Diffusion of Video Stream Fragment into SNS The user terminal 118-i according to the present embodiment specifies an arbitrary reproduction time of the real-time video stream while watching the real-time video stream, and the SNS service provider 116. The video stream fragment corresponding to the designated reproduction time can be posted to the SNS site via. 27 to 29 are diagrams showing an operation when posting a video stream fragment corresponding to a designated reproduction time to an SNS site.

As shown in FIG. 27, when the user i touches the paper airplane mark in the lower right portion of the screen of the display unit 210 of the user terminal 118-i, a diffusion screen in which a comment can be input is displayed. As shown in FIG. 28, when the user i inputs a comment and then touches the display called tweet in the lower right part of the screen, the video stream fragment and the comment corresponding to the playback time specified on the SNS site are posted. To be done.

FIG. 24 is a sequence diagram showing a first embodiment of spreading video stream fragments to the SNS.

The content distribution server 122 of the content provider 114 distributes the real-time video stream to the _first user terminal 118-i ₁ (step S2402). At this time, the first user terminal 118-i ₁ temporarily buffers the received real-time video stream after receiving the real-time video stream, and buffers the received real-time video stream after a predetermined time (about 2 seconds) from the reception time. Play the real-time video stream that you have done. When the user i designates the video stream fragment corresponding to the reproduction time while watching the real-time video stream, the first user terminal 118-i ₁ transmits a video stream fragment selection signal to the content provider 114 (step S2404). Here, since the RTP header portion 1202 received by the _first user terminal 118-i ₁ includes a sequence number that is a counter of the RTP packet and a time stamp that is the sampling time of the first byte of the payload data, The first user terminal 118-i ₁ transmits the video stream fragment selection signal by including the sequence number and the time stamp as the information for designating the specified video stream fragment. Also, in the case of distribution according to the HLS protocol, the index file received by the _first user terminal 118-i ₁ includes information regarding the positions of a plurality of media files to be played, so the first user terminal 118-i ₁ is, as information for specifying the selected video streams fragment, transmits including information about the location of the media files to a video stream fragment selection signal. Furthermore, in the case of distribution according to the MPEG-DASH (Dynamic Adaptive Streaming over HTTP) protocol, the MPD file received by the _first user terminal 118-i ₁ includes information about the program timing and the acquisition destination of the media file. Therefore, the information about the program timing and the acquisition source of the media file is included in the video stream fragment selection signal and transmitted.

Upon receiving the video stream fragment selection signal, the content provider 114 identifies the selected video stream fragment and stores the identified video stream fragment (step S2406). Here, the header portion 904 of each video stream fragment stored in the content database 510 of the database server 124 stores address information indicating a storage position of encoded data and header information such as decoding and display time. Therefore, the content provider 114 can identify the selected video stream fragment based on these pieces of information. The first user terminal 118-i ₁ sends a message posting and posting request for the selected video stream fragment to the SNS service provider 116 (step S2408). The SNS service provider 116 stores and displays the posted message (step S2410).

The second user terminal _{118-i 2} transmits a viewing request of Posts and selected video stream fragments SNS service provider 116 (step S2412). The SNS service provider 116 notifies the content provider 114 that there is a message posted and a browse request for the selected video stream fragment (step S2414). The SNS service provider 116 transmits the content of the posted message to the _second user terminal 118-i2 (step S2416), and the content provider 114 is selected by the _second user terminal 118-i2. The transmitted video stream fragment is transmitted (step S2418).

In this embodiment, the selected video stream fragments are not stored on the database server 130 of the SNS service provider 116.

Further, according to the present embodiment, by using only the user terminal 118-i, while watching the real-time video stream on the user terminal 118-i, the SNS of the video stream fragment at an arbitrary position of the real-time video stream. Posting to the site is possible in a simple way. This is possible by using the storage method of the real-time video stream shown in FIG. 10 in the database server 124 and the delivery method of the real-time video stream shown in FIGS. 11 to 13 and FIGS. 17 and 18. Is.

FIG. 25 is a sequence diagram showing a second embodiment of spreading video stream fragments to the SNS.

The content distribution server 122 of the content provider 114 distributes the real-time video stream to the _first user terminal 118-i ₁ (step S2502). When the user i designates the video stream fragment corresponding to the reproduction time while watching the real-time video stream, the first user terminal 118-i ₁ transmits a video stream fragment selection signal to the content provider 114 (step S2504). Here, since the RTP header portion 1202 received by the _first user terminal 118-i ₁ includes a sequence number that is a counter of the RTP packet and a time stamp that is the sampling time of the first byte of the payload data, The first user terminal 118-i ₁ transmits the video stream fragment selection signal by including the sequence number and the time stamp as the information for designating the specified video stream fragment. Also, in the case of distribution according to the HLS protocol, the index file received by the _first user terminal 118-i ₁ includes information regarding the positions of a plurality of media files to be played, so the first user terminal 118-i ₁ is, as information for specifying the selected video streams fragment, transmits including information about the location of the media files to a video stream fragment selection signal. Furthermore, in the case of distribution according to the MPEG-DASH protocol, the MPD file received by the _first user terminal 118-i ₁ contains the information about the program timing and the acquisition destination of the media file, so the program timing And information about the acquisition source of the media file is included in the video stream fragment selection signal and transmitted.

The first user terminal 118-i ₁ downloads the selected video stream fragment from the content provider 114 (step S2506). At this time, the header portion 904 of each video stream fragment stored in the content database 510 of the database server 124 stores address information indicating the storage position of encoded data and header information such as decoding and display time. Therefore, the content provider 114 can obtain the selected video stream fragment based on these pieces of information. The first user terminal 118-i ₁ stores the downloaded selected video stream fragment (step S2508). The first user terminal 118-i ₁ sends a message posting request and posting request for the selected video stream fragment to the SNS service provider 116 (step S2510), and uploads the selected video stream fragment to the SNS service provider 116. (Step S2512). The SNS service provider 116 stores the uploaded selected video stream fragment in the video stream fragment database 710 of the database server 130 (step S2514).

The second user terminal _{118-i 2} transmits a viewing request of Posts and selected video stream fragments SNS service provider 116 (step S2516). The SNS service provider 116 transmits the content of the posted message to the _second user terminal 118-i ₂ (step S2518), and also sends the selected video stream fragment to the second user terminal 118-i _2. It is transmitted (step S2520).

According to the present embodiment, by using only the user terminal 118-i, while watching the real-time video stream on the user terminal 118-i, the SNS site of the video stream fragment at an arbitrary position of the real-time video stream can be accessed. Can be posted in a simple way. This is possible by using the storage method of the real-time video stream shown in FIG. 10 in the database server 124 and the delivery method of the real-time video stream shown in FIGS. 11 to 13 and FIGS. 17 and 18. Is.

FIG. 26 is a sequence diagram showing a third embodiment of spreading video stream fragments to the SNS.

The content distribution server 122 of the content provider 114 distributes the real-time video stream to the _first user terminal 118-i ₁ (step S2602). When the user i specifies the video stream fragment corresponding to the reproduction time while watching the real-time video stream, the first user terminal 118-i ₁ transmits a video stream fragment selection signal to the content provider 114 (step S2604). Here, since the RTP header portion 1202 received by the _first user terminal 118-i ₁ includes a sequence number that is a counter of the RTP packet and a time stamp that is the sampling time of the first byte of the payload data, The first user terminal 118-i ₁ transmits the video stream fragment selection signal by including the sequence number and the time stamp as the information for designating the specified video stream fragment. Also, in the case of distribution according to the HLS protocol, the index file received by the _first user terminal 118-i ₁ includes information regarding the positions of a plurality of media files to be played, so the first user terminal 118-i ₁ is, as information for specifying the selected video streams fragment, transmits including information about the location of the media files to a video stream fragment selection signal. Furthermore, in the case of distribution according to the MPEG-DASH protocol, the MPD file received by the _first user terminal 118-i ₁ contains the information about the program timing and the acquisition destination of the media file, so the program timing And information about the acquisition source of the media file is included in the video stream fragment selection signal and transmitted.

Upon receiving the video stream fragment selection signal, the content provider 114 identifies the selected video stream fragment and stores the identified video stream fragment (step S2606). Here, the header portion 904 of each video stream fragment stored in the content database 510 of the database server 124 stores address information indicating a storage position of encoded data and header information such as decoding and display time. Therefore, the content provider 114 can identify the selected video stream fragment based on these pieces of information. The first user terminal 118-i ₁ sends a message post and a posting request for the selected video stream fragment to the content provider 114 (step S2608), and the content provider 114 sends the message post and the request to the SNS service provider 116. A posting request for the selected video stream fragment is transmitted (step S2616). The SNS service provider 116 stores and displays the posted message (step S2612).

The second user terminal _{118-i 2} is the content provider 114 transmits a browse request of Posts and selected video stream fragments (step S2614), the content provider 114, the SNS service provider 116, the A request for viewing the posted message and the selected video stream fragment is transmitted (step S2616). Content provider 114, the SNS service provider 116 transmits the video stream fragments that have been selected (step S2618), SNS service provider 116, the second user terminal _{118-i 2,} sends a video stream fragments that have been selected Yes (step S2620). The SNS service provider 116 transmits the content of the posted message to the _second user terminal 118-i2 (step S2622).

According to the present embodiment, by using only the user terminal 118-i, while watching the real-time video stream on the user terminal 118-i, the SNS site of the video stream fragment at an arbitrary position of the real-time video stream can be accessed. Can be posted in a simple way. This is possible by using the storage method of the real-time video stream shown in FIG. 10 in the database server 124 and the delivery method of the real-time video stream shown in FIGS. 11 to 13 and FIGS. 17 and 18. Is.

As shown in FIG. 29, when the second user terminal 118-i ₂ browses the selected video stream fragment, “content” stored in the user posting history database 714 of the database server 130 of the SNS service provider 116 is displayed. For each content identified by id"l and for each posted message, the sequence of the "user id" that posted the content and the sequence of the "user id" that posted the message are displayed in the form of a list To be done.

Each step of the above method according to the present invention may be performed by an operator's terminal (not shown) having a CPU and a memory. In an embodiment of the present invention, the software program used to carry out the above method may be stored in a program storage device such as a digital data storage medium. Are machine-readable or computer-readable, and these computers or machines encode program instructions as machine-executable programs, or computer-executable programs, the encoded program instructions being methods of the present invention. Perform some or all of the steps. The program storage device can be, for example, a digital memory, a magnetic storage medium such as a magnetic disk and a magnetic tape, a hard drive, or an optically readable digital data storage medium.

The present invention is software, and/or a combination of software and hardware, for example, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), and a combination of an application specific integrated circuit (ASIC) and a field programmable gate array (FPGA). It may be implemented using a general purpose computer, or any other hardware equivalent.

The above description merely provides a disclosure of particular embodiments of the invention and is not intended for the purposes of limiting the same thereto. Therefore, it is appreciated that the invention is not limited to only the embodiments described above, but rather that one of ordinary skill in the art may devise alternative embodiments that fall within the scope of the invention.

100: radio communication network 102: upper network 104: mobile communication network 106: content service router 108: radio network controller (RNC)
110: NodeB
112: eNodeB

Claims (9)

A content distribution system including a user terminal connected to a communication network, a content provider, and an SNS service provider,
The content provider receives means for storing a real-time video stream including a plurality of video stream fragments, and a selection signal of the video stream fragment B from the first user terminal that transmitted the real-time video stream A, and the video stream fragment B. And a means for transmitting the stored video stream fragment B to the second user terminal in response to the notification of the browsing request for the video stream fragment B transmitted from the SNS service provider.
As the first user terminal, the user terminal receives the user input for selecting the video stream fragment B during the reproduction of the real-time video stream A transmitted from the content provider, and the user terminal related to the video stream fragment B. The video stream fragment B includes means for transmitting a selection signal to the content provider, means for transmitting a posting request for the video stream fragment B to the SNS service provider together with a message C, and the video stream fragment B as the second user terminal. Means for transmitting the browsing request to the SNS service provider, and the video stream fragment B transmitted from the content provider while displaying the message C transmitted from the SNS service provider in response to the browsing request. And means for reproducing,
The SNS service provider stores the message C transmitted together with the posting request from the first user terminal, publishes the message C in the user terminal, and stores the message C in the user terminal. Means for transmitting the message C to the second user terminal in response to a browsing request for the video stream fragment B from the user terminal, and transmitting a notification of the browsing request for the video stream fragment B to the content provider. With
Content distribution system. A content distribution system including a user terminal connected to a communication network, a content provider, and an SNS service provider,
The content provider receives means for storing a real-time video stream including a plurality of video stream fragments, and a selection signal of the video stream fragment B from the first user terminal that transmitted the real-time video stream A, and the video stream fragment B. To store the posting request for the video stream fragment B and the message C sent from the first user terminal to the SNS service provider, and to send the request from the second user terminal. Upon receiving a browsing request for the video stream fragment B and the message C, means for transmitting the browsing request and the stored video stream fragment B to the SNS service provider,
As the first user terminal, the user terminal receives the user input for selecting the video stream fragment B during the reproduction of the real-time video stream A transmitted from the content provider, and the user terminal related to the video stream fragment B. A means for transmitting a selection signal to the content provider, a means for transmitting a posting request for the video stream fragment B to the content provider together with a message C, and the video stream fragment B as the second user terminal A means for transmitting a browsing request for the message C to the content provider, and the message C and the video stream fragment B when the SNS service provider transmits the browsing request as a source. And means for playing back the video stream fragment B,
The SNS service provider stores the posting request of the video stream fragment B transferred from the content provider and the message C, publishes the message C to the user terminal, and the content provider. Means for transmitting the video stream fragment B and the message C to the second user terminal upon receiving the browsing request for the video stream fragment B and the message C transmitted from With and
Content distribution system. Oite to claim 1 or claim 2, wherein the real-time video stream, the stored in the content provider video stream fragments as the minimum unit of division, the content distribution system. Posting the video stream fragment to the SNS service provider by a content delivery system including a user terminal connected to a communication network, a content provider storing a real-time video stream including a plurality of video stream fragments, and an SNS service provider. Method,
The first user terminal receiving the real-time video stream A from the content provider transmits a selection signal of the video stream fragment B,
The content provider receives the selection signal of the video stream fragment B and stores the video stream fragment B,
The first user terminal sends a posting request of the video stream fragment B to the SNS service provider together with a message C,
The SNS service provider stores the message C transmitted together with the posting request from the first user terminal, and posts the message C to the user terminal,
A second user terminal sends a viewing request for the video stream fragment B to the SNS service provider,
The SNS service provider sends the message C to the second user terminal in response to the viewing request for the video stream fragment B from the second user terminal, and notifies the viewing request for the video stream fragment B. To the content provider,
The content provider transmits the stored video stream fragment B to the second user terminal in response to the notification of the browsing request for the video stream fragment B transmitted from the SNS service provider,
The second user terminal displays the message C sent from the SNS service provider and plays the video stream fragment B sent from the content provider .
How to post a video stream fragment . Posting the video stream fragment to the SNS service provider by a content delivery system including a user terminal connected to a communication network, a content provider storing a real-time video stream including a plurality of video stream fragments, and an SNS service provider. Method,
The first user terminal receiving the real-time video stream A from the content provider transmits a selection signal of the video stream fragment B,
The content provider receives the selection signal of the video stream fragment B and stores the video stream fragment B,
The first user terminal sends a posting request for the video stream fragment B with the message C to the content provider,
The content provider transfers the posting request of the video stream fragment B and the message C transmitted from the first user terminal to the SNS service provider,
The SNS service provider stores a posting request of the video stream fragment B transferred from the content provider and a message C, and posts the message C to the user terminal,
A second user terminal sends a viewing request for the video stream fragment B and the message C to the content provider;
When the content provider receives a browsing request for the video stream fragment B and the message C transmitted from the second user terminal, the content provider transmits the browsing request and the stored video stream fragment B to the SNS service provider. Then
When the SNS service provider receives the browse request for the video stream fragment B and the message C transmitted from the content provider and the video stream fragment B, the SNS service provider receives the video stream fragment B and the message C. Send it to the second user terminal,
When the message C and the video stream fragment B are transmitted from the SNS service provider, the second user terminal displays the message C and reproduces the video stream fragment B.
How to post a video stream fragment . The method of posting a video stream fragment according to claim 4 or 5 , wherein the real-time video stream is stored in the content provider by using the video stream fragment as a minimum unit of division . By being processed by a user terminal that is connected to a communication network to form a content distribution system, a content provider that stores a real-time video stream including a plurality of video stream fragments, and an SNS service provider,
Causing a first user terminal, which has received the real-time video stream A from the content provider, to transmit a selection signal of a video stream fragment B;
Causing the content provider to receive a selection signal of the video stream fragment B and store the video stream fragment B;
The first user terminal sending a posting request for the video stream fragment B with the message C to the content provider;
Causing the content provider to transfer the posting request of the video stream fragment B and the message C transmitted from the first user terminal to the SNS service provider;
Causing the SNS service provider to store a posting request of the video stream fragment B transferred from the content provider and a message C, and posting the message C to the user terminal;
Causing a second user terminal to send a browsing request for the video stream fragment B and the message C to the content provider;
The content provider is caused to receive a browsing request for the video stream fragment B and the message C transmitted from the second user terminal, and the SNS service provider stores the browsing request and the stored video stream fragment. Sending B,
The SNS service provider is caused to receive the browsing request for the video stream fragment B and the message C and the video stream fragment B transmitted from the content provider, and the video stream fragment B and the message C are received. Causing the second user terminal to transmit,
When the message C and the video stream fragment B are transmitted from the SNS service provider to the second user terminal, displaying the message C and reproducing the video stream fragment B,
A program for posting a video stream fragment that executes . By being processed by a user terminal, a content provider that stores a real-time video stream including a plurality of video stream fragments, and a SNS service provider that are connected to a communication network to form a content distribution system,
Causing a first user terminal, which has received the real-time video stream A from the content provider, to transmit a selection signal of a video stream fragment B;
Causing the content provider to receive a selection signal of the video stream fragment B and store the video stream fragment B;
Causing the first user terminal to send a posting request of the video stream fragment B to the content provider together with a message C,
Causing the content provider to transfer the posting request of the video stream fragment B and the message C transmitted from the first user terminal to the SNS service provider;
Causing the SNS service provider to store the posting request of the video stream fragment B transferred from the content provider and the message C, and causing the message C to be posted to the user terminal;
Causing a second user terminal to send a browse request for the video stream fragment B and the message C to the content provider;
The content provider is caused to receive a browsing request for the video stream fragment B and the message C transmitted from the second user terminal, and the SNS service provider stores the browsing request and the stored video stream fragment B. To send
The SNS service provider is caused to receive the browsing request for the video stream fragment B and the message C transmitted from the content provider, and the video stream fragment B, and the video stream fragment B and the message C are received. Is transmitted to the second user terminal,
When the message C and the video stream fragment B are transmitted from the SNS service provider to the second user terminal, displaying the message C and reproducing the video stream fragment B,
A program for posting a video stream fragment that executes . The video stream fragment posting program according to claim 7 or 8, wherein the real-time video stream is stored in the content provider with the video stream fragment as a minimum unit of division .