JP2006157278A - Information distribution system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an information distribution system capable of reproducing video contents and collateral information synchronously with each other even if the video contents and the collateral information are distributed from different places. <P>SOLUTION: A video content distributor 1 in the information distribution system distributes contents including video and audio in a streaming distribution way and transmits a transmission start time of the contents. A collateral information content distributor 2 distributes the collateral information on the basis of the content transmission start time transmitted from the video content distributor 1. A client terminal 3 reproduces the video and audio from the video content distributor 1 and the collateral information from the collateral information content distributor 2 synchronously with each other. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an information distribution system for distributing arbitrary content by streaming and distributing additional information for display in synchronization with the content.

  A conventional information distribution system has realized a distribution function of content consisting of video and audio and additional information by means according to a transmission method of digital broadcasting. For example, as in the data broadcasting transmission method described in Non-Patent Document 1, after the additional information such as the data broadcasting content is accommodated in the transport stream packet (hereinafter abbreviated as TS packet), the content including video / audio is included. Transmission is performed as one transport stream by multiplexing packets with TS packets. This makes it possible to synchronize the additional information with the content composed of video and audio.

"Data Broadcast Coding and Transmission Methods in Digital Broadcasting" (ARIB STD-B24 3.0 Edition, 1st volume), Japan Radio Industry Association Publishing, May 31, 2001, P6-8

  Since the conventional information distribution system has been realized by the means as described above, when synchronously distributing video / audio content (hereinafter abbreviated as video content) and additional information content, video content and additional information content Are aggregated in one information distribution apparatus, and TS packets are multiplexed in the information distribution apparatus, and then transmitted as one transport stream. However, in such a conventional method, an information distribution device that distributes video content (hereinafter referred to as a video content distribution device) and an information distribution device that distributes additional information content (hereinafter referred to as an additional information content distribution device). As another device, it could not cope with various distribution forms such as installing in different areas and transmitting. In particular, there has been a problem that the video content and the additional information content cannot be transmitted in synchronization with the video content distribution device and the additional information content distribution device installed in different places.

  The present invention has been made to solve the above-described problems, and provides an information distribution system that can be reproduced in a synchronized state even when video content and additional information content are distributed from different locations. With the goal.

  The information distribution system according to the present invention performs streaming distribution of arbitrary content and synchronizes with the content based on the content distribution device that transmits the transmission start time of the content and the content transmission start time transmitted from the content distribution device. And an additional information distribution device that distributes additional information for reproduction, and the client terminal device reproduces the content distributed from the content distribution device and the additional information distributed from the additional information distribution device. Is.

  Since the information distribution system of the present invention transmits the transmission start time from the content distribution device, and the additional information distribution device distributes the additional information at this transmission start time, for example, the content distribution device and the additional information distribution device Even if these are installed at different locations, the client terminal device can reproduce the content and the additional information in a synchronized state.

Embodiment 1 FIG.
1 is a block diagram showing an information distribution system according to Embodiment 1 of the present invention.
In the figure, the information distribution system includes a video content distribution apparatus (content distribution apparatus) 1, an additional information content distribution apparatus (additional information distribution apparatus) 2, a client terminal apparatus 3, and a network 4. The video content distribution apparatus 1 has a function of streaming content including video and audio and transmitting transmission start time information when the content is distributed. The additional information content distribution device 2 is a device that performs streaming distribution of additional information such as banner advertisement information and commentary information on video content. The additional information content distribution device 2 is based on the content transmission start time transmitted from the video content distribution device 1. Configured to be delivered. The client terminal device 3 is a device that reproduces content including additional information by displaying the received video content and additional information content in synchronization. The network 4 is a network that transmits IP packets by, for example, the Internet protocol.

Next, the operation of the information distribution system according to this embodiment will be described.
FIG. 2 is an explanatory diagram showing an operation sequence of the present embodiment.
The video content distribution device 1 performs streaming distribution of the video content to the client terminal device 3 via the network 4 according to a distribution schedule specified in advance. At this time, when the additional information content is also distributed along with the video content, the video content distribution device 1 transmits a distribution start request packet including the distribution start time Tv of the video content to the additional information content distribution device 2. .

  The video content distribution apparatus 1 transmits a distribution start request packet to the additional information content distribution apparatus 2 at time Tv-Td. Here, Td is a preset time length in anticipation of additional information distribution preparation and network transmission delay of the distribution start request packet. For example, when the distribution start time Tv is 13:00 and the time length Td is 10 seconds, the video content distribution apparatus 1 sends the additional information content distribution apparatus 2 to the additional information content distribution apparatus 2 at 12:59:50 (Tv-Td). The transmission start request packet is transmitted.

FIG. 3 is a diagram illustrating a configuration of a packet used when transmitting a distribution control packet including a distribution start request packet.
FIG. 4 is an explanatory diagram of control data of a distribution control packet.
The distribution control packet is a packet transmitted in accordance with the TCP / IP protocol, and includes a control command and control information as control data inside the packet as shown in FIG. This control data is defined as shown in FIG. Further, the control command can have control information to be transmitted at the same time, and the correspondence relationship is also shown in FIG. In the figure, VS indicates the video content distribution apparatus 1, and AS indicates the additional information content distribution apparatus 2.

The distribution start request packet used in the operation sequence of FIG. 2 includes a “distribution start request” command shown in FIG. 4 and has “distribution start time” as control information. The “transmission delay time measurement value” described in the control information column of FIG. 4 is not used in this embodiment (it is a value used in Embodiment 3), and will be described later.
The additional information content distribution apparatus 2 starts distributing the additional information content based on the “distribution start time” described in the control information of the “distribution start request” command received via the network 4.

FIG. 5 is an explanatory diagram of a content transmission packet, where (a) shows a video content transmission packet and (b) shows an additional information content transmission packet.
When the video content distribution apparatus 1 distributes video content, the video content transmission packet shown in FIG. 5A is used. The packet for video transmission includes “RTP header”, “relative transmission time”, and “video content” in the UDP / IP payload. Here, the “RTP header” conforms to the specifications described in RFC 3550 “RTP: A Transport Protocol for Real-Time Applications” of the IETF standard. The “relative transmission time” in the figure is not used in this embodiment (used in Embodiment 2), and will be described later. When the additional information content distribution apparatus 2 distributes the additional information content, the additional information content transmission packet shown in FIG. 5B is used. The additional information content transmission packet includes “relative transmission time” and “additional information content” in the UDP / IP payload.

The client terminal device 3 displays the video content received from the video content distribution device 1 and the additional information content received from the additional information content distribution device 2 on a display screen (not shown) of the client terminal device 3.
As described above, since the “distribution start time” information is transmitted between the video content distribution apparatus 1 and the additional information content distribution apparatus 2 using the distribution control packet, the distribution of the additional information content is performed using the video. It can be performed in synchronization with the content distribution.

  As described above, according to the information distribution system of the first embodiment, the content distribution device that distributes arbitrary content while streaming the content transmission start time, and the content transmission start time transmitted from the content distribution device , An additional information distribution device that distributes additional information for reproduction in synchronization with content, a content distributed from the content distribution device, and a client terminal device that reproduces additional information distributed from the additional information distribution device Therefore, even if the content distribution device and the additional information distribution device are installed at different locations, the client terminal device can reproduce the content and the additional information in a synchronized state.

Embodiment 2. FIG.
In the first embodiment described above, the video content distribution device 1 and the additional information content distribution device 2 are synchronously distributed using the distribution control packet. For example, the video content distribution device 1, When the installation location of the additional information content distribution device 2 is greatly different, the transmission path of the video content transmission packet transmitted between the video content distribution device 1 and the client terminal device 3, the additional information content distribution device 2 and the client terminal It is assumed that the transmission path of the additional information content transmission packet transmitted between the apparatuses 3 is significantly different. As a result, it may be assumed that the transmission delay time required for transmitting the video content transmission packet and the transmission delay time required for transmitting the additional information content transmission packet are significantly different.

In such a case, the distribution start time of the video content in the video content distribution device 1 and the distribution start time of the additional information content in the additional information content distribution device 2 can be made the same time using the distribution control packet. However, since the arrival time of the video content transmission packet and the arrival time of the additional information content transmission packet at the client terminal device 3 are different, the additional information content is displayed in synchronization with the video content at the client terminal device 3. It becomes impossible to do.
Therefore, in the information distribution system according to the second embodiment, the “relative transmission time” that is the transmission time of each content is included in the video content transmission packet and the additional information content transmission packet. Here, the “relative transmission time” included in the video content is a transmission time display of the video content transmission packet with the origin point “0” as the video content distribution start time, and the “relative transmission time” included in the additional information content. Is a transmission time display of the additional information content transmission packet with the origin of distribution start time of the additional information content as “0”.

  That is, the information distribution system of the second embodiment includes a video content distribution device 1, an additional information content distribution device 2, a client terminal device 3, and a network 4, and the configuration on these drawings is the same as that of the first embodiment. Therefore, FIG. 1 is used for explanation. When distributing the content, the video content distribution apparatus 1 according to the second embodiment distributes the content by adding the relative transmission time of the content, and the additional information content distribution apparatus 2 distributes the additional information. The additional information is delivered by adding the relative transmission time of the additional information. Further, the client terminal device 3 processes the content received from the video content distribution device 1 to display video / audio, and displays the additional information received from the additional information content distribution device 2 together with the video / audio, In addition, based on the relative transmission time of the content and the relative transmission time of the additional information, these processing timings are adjusted so that the display timings of the video / audio and the additional information match.

FIG. 6 is a configuration diagram of the client terminal device 3.
As illustrated, the client terminal device 3 includes a transmission relative time comparator 5, a video packet reception buffer 6, an additional information packet reception buffer 7, a buffer read control unit 8, a video decoding processing unit 9, and an additional information decoding processing unit 10. I have. Here, the transmission relative time comparator 5 refers to the relative transmission time included in the video content transmission packet and the relative transmission time included in the additional information content transmission packet, and then transmits the video content transmission packet to be transmitted next. Has the function of outputting the storage location information in the additional information packet reception buffer 7 of the additional information content transmission packet having the same relative transmission time as the relative transmission time included in. The video packet reception buffer 6 is a buffer for temporarily storing received video content transmission packets, and the additional information packet reception buffer 7 is a buffer for temporarily storing received additional information content transmission packets. The buffer read control unit 8 is a control unit that controls reading of the additional information content transmission packet from the additional information packet reception buffer 7 based on the information from the transmission relative time comparator 5. The video decoding processing unit 9 is a decoder that decodes video content transmission packets stored in the video packet reception buffer 6 and outputs them as video signals. The additional information decoding processing unit 10 is a decoder that decodes the additional information content transmission packet stored in the additional information packet reception buffer 7 and outputs it as an additional information display signal.

Next, the operation of the information distribution system according to the second embodiment will be described.
As shown in FIG. 5A, the video content distribution apparatus 1 transmits the video content transmission packet including the “relative transmission time” when transmitting the video content transmission packet. Further, as illustrated in FIG. 5B, the additional information content distribution device 2 transmits a packet including “relative transmission time” when transmitting the additional information content transmission packet.
The client terminal device 3 accumulates the received video content transmission packet in the video packet reception buffer 6 and accumulates the received additional information content transmission packet in the additional information packet reception buffer 7. The video decoding processing unit 9 sequentially reads out the packets stored in the video packet receiving buffer 6, performs processing such as a video code decoder, and outputs a video signal.

  The transmission relative time comparator 5 extracts and stores the “relative transmission time” included in the packet to be read next from the video packet reception buffer 6 and stores the packet included in the additional information packet reception buffer 7. The “relative transmission time” is checked, an additional information packet having the “relative transmission time” that is the same as the “relative transmission time” extracted from the video packet reception buffer 6 is selected, and the selected packet is stored in the buffer. The position is output to the buffer read control unit 8. The buffer read control unit 8 reads the previously selected additional information packet from the storage position in the buffer at the timing when the video packet is read from the video packet reception buffer 6, and outputs it to the additional information decoding processing unit 10. As a result, the additional information decoding processing unit 10 decodes the additional information packet and outputs an additional information display signal for displaying the additional information.

The operation of the transmission relative time comparator 5 will be specifically described.
FIG. 7 shows the state of packets stored in the video packet reception buffer 6 and the additional information packet reception buffer 7 at a certain time.
As shown in the figure, each buffer stores a “transmission relative time” value included in the received packet and the contents of each content. For example, the video packet reception buffer 6 has the video content V20 at the transmission relative time = 20, and the additional information packet reception buffer 7 has the additional information content A25 at the transmission relative time = 25.
The transmission relative time comparator 5 extracts the “relative transmission time” value of the video packet to be read out next included in the video packet reception buffer 6. Hereinafter, this “relative transmission time” value is referred to as TRv. In the case of FIG. 7, the “relative transmission time” value is TRv = 20 corresponding to the video content V20. Next, the transmission relative time comparator 5 is a packet stored in the additional information packet reception buffer 7 and whose transmission relative time value (hereinafter referred to as “relative transmission time” value is referred to as TRa) is TRa = 20. Search for. In the case of FIG. 7, the packet that is the additional information content A20 corresponds to this, and the transmission relative time comparator 5 outputs the storage position of the packet in the additional information packet reception buffer 7. Based on the packet read signal from the video packet reception buffer 6, the buffer read control unit 8 transmits a read signal including the storage position information of the read packet to the additional information packet reception buffer 7, thereby the additional information of TRa = 20. The packet is read and output to the additional information decoding processing unit 10.

  As described above, since the “relative transmission time” value is included in the transmission packet, and the read control from the reception buffer of the additional information packet in the client terminal device 3 is performed based on the “relative transmission time” value, Even when there is a transmission delay time difference between the video content transmission packet and the additional information content transmission packet, the video content and the additional information content can be displayed in synchronization.

  In the above description, when searching for a packet in the additional information packet reception buffer 7, an additional information packet having the same “relative transmission time” value as the “relative transmission time” value of the video packet to be read out next is selected. However, for example, an additional information packet in the range of TRv−Δ <TRa <TRv + Δ may be selected with some allowance. Here, Δ is an allowable error of synchronization.

  As described above, according to the information distribution system of the second embodiment, when distributing a content, the content distribution device adds the relative transmission time of the content and distributes the content. Is distributed with the relative transmission time of the additional information, and the client terminal device displays the content and the additional information in synchronization based on the relative transmission time of the content and the relative transmission time of the additional information. Since these processing timings are adjusted so as to be played back, even if the transmission delay time required for content transmission differs significantly from the transmission delay time required for additional information transmission, Additional information can be reproduced in synchronization.

Embodiment 3 FIG.
In the second embodiment, the value of “relative transmission time” is used to display the video content and the additional information content in synchronization with each other. However, when the transmission delay time difference is very large, The buffer control alone in the client terminal device 3 makes it difficult to absorb this transmission delay time difference. Therefore, in the video distribution system according to the third embodiment, before the video content distribution device 1 starts distributing the video content or before the additional information content distribution device 2 starts distributing the additional information content, the client terminal device 3 The video content distribution device 1 and the additional information content distribution device 2 respectively measure the transmission delay time, and adjust the distribution start time of the video content and the additional information content based on the measured value of the transmission delay time. It is what I did.

  Also in the third embodiment, since the configuration on the drawing is the same as that of the first embodiment, FIG. The video content distribution apparatus 1 according to the third embodiment measures the transmission delay time between the video content distribution apparatus 1 and the client terminal apparatus 3 and notifies the additional information content distribution apparatus 2 of the measured transmission delay time. When receiving information on the desired time of content distribution from the information content distribution apparatus 2, the transmission start time is reset. The additional information content distribution device 2 measures the transmission delay time between the additional information content distribution device 2 and the client terminal device 3, and uses this transmission delay time and the transmission delay time notified from the video content distribution device 1. By comparing, it is configured to adjust the distribution start time of the additional information, and when the additional information cannot be distributed at the transmission start time notified from the video content distribution device 1, the video content distribution device 1 Is notified of the desired time to start transmission. The client terminal device 3 is the same as the client terminal device 3 of the first embodiment.

Next, the operation of the information distribution system according to the third embodiment will be described.
FIG. 8 is an explanatory diagram showing an operation sequence of the third embodiment.
FIG. 9 is a flowchart showing the operation of the third embodiment.
The scheduled distribution start time of the video content is Tv. The transmission delay time is measured between the video content distribution apparatus 1 and the client terminal apparatus 3 before the distribution start scheduled time Tv (step ST1). Here, the Td value is a preset value. The delay time measurement uses, for example, a ping command supported by a normal server or personal computer. The measured transmission delay time measurement value is defined as TDv. The video content distribution apparatus 1 instructs the additional information content distribution apparatus 2 to start distributing additional information using the distribution control packet shown in FIG. 3 (step ST2). In the distribution control packet, a “distribution start request” is set as a control command, a “distribution start time” is set as control information, and the TDv value is set as a “transmission delay time measured value”.

  The additional information content distribution device 2 that has received the distribution control packet measures the transmission delay time between the additional information content distribution device 2 and the client terminal device 3 using the same means as the video content distribution device 1 (step ST3). . The measured transmission delay time measurement value is defined as TDa. The additional information content distribution apparatus 2 calculates a time difference ΔD = TDv−TDa between TDa and TDv (step ST4). When ΔD> 0, the additional information content distribution start time Ta is set to Ta = Tv + ΔD (step ST5). On the other hand, even when ΔD <0, additional information content distribution apparatus 2 sets additional information content distribution start time Ta to Ta = Tv + ΔD (step ST6). However, if this Ta is earlier than the current time, control is impossible (step ST7), and the additional information content distribution device 2 requests adjustment of the distribution start time using the distribution control packet (step ST7). ST8).

  In the distribution control packet, as shown in FIG. 4, “distribution start time adjustment request” is set as “control command” and “desired distribution start time” is set as “control information”. Here, the value of “desired distribution start time” is Tv + D. Here, D is a value such that D> | ΔD |. When receiving the “distribution start time adjustment request” command by the distribution control packet, the video content distribution apparatus 1 resets the distribution start time based on the “desired distribution start time”, and the additional information content distribution apparatus 2 In response to this, a “distribution start reset” command by the distribution control packet is transmitted (step ST9). As shown in FIG. 4, the “reset distribution start” command includes the reset distribution start time as “distribution start time” as control information.

  The additional information content distribution apparatus 2 that has received the “reset distribution start” command sets “distribution start time” included in the “reset distribution start” command to Tv2, and resets the distribution start time of additional information content as Ta = Tv2 + ΔD. Then (step ST10), the video content distribution apparatus 1 and the additional information content distribution apparatus 2 execute distribution of the video content and the additional information content, respectively (step 11).

  As described above, according to the information distribution system of the third embodiment, the content distribution device notifies the additional information distribution device of the transmission delay time between the content distribution device and the client terminal device. Since the transmission start time of the additional information is adjusted by comparing the transmission delay time notified from the content distribution device and the transmission delay time between the additional information distribution device and the client terminal device, the transmission is performed through the transmission path. Even when the delay time difference is large, the content and the additional information can be reproduced in synchronization.

  Further, according to the information distribution system of the third embodiment, the additional information distribution device transmits to the content distribution device when the additional information cannot be distributed based on the transmission start time notified from the content distribution device. Since the content distribution apparatus receives the information on the desired time and resets the transmission start time, the transmission delay time of the additional information distribution apparatus is determined from the transmission delay time of the content distribution apparatus. Even when the content is large, the content and the additional information can be reproduced in synchronization.

  In the third embodiment, the transmission delay time is measured before starting the content distribution. However, the transmission delay time may be periodically measured even after the content distribution is started. That is, the content distribution device and the additional information distribution device periodically measure the transmission delay time between the content distribution device and the client terminal device, and between the additional information distribution device and the client terminal device, and measure the transmission delay time. The timing for transmitting the additional information in the additional information distribution apparatus may be adjusted based on the value. In this way, even when the delay time fluctuates during content distribution, it is possible to adjust the shift in the transmission timing of the additional information due to this.

Furthermore, it is good also as a structure which combined the said Embodiment 2 and Embodiment 3. FIG. In this way, the synchronized playback of the content and the additional information can be further reliably performed.
In the first to third embodiments, the service for distributing video / audio contents such as broadband broadcasting in the IP network has been described in mind. However, the information distribution system of the present invention is limited to these embodiments. Any content and additional information can be applied. The network 4 may also be a network of an arbitrary protocol, not an IP network.

BRIEF DESCRIPTION OF THE DRAWINGS It is a block diagram which shows the information delivery system by Embodiment 1 of this invention. It is explanatory drawing which shows the operation | movement sequence of the information delivery system by Embodiment 1 of this invention. It is explanatory drawing which shows the format of the packet for delivery control in the information delivery system by Embodiment 1 of this invention. It is explanatory drawing which shows the control data of the packet for a delivery control in the information delivery system by Embodiment 1 of this invention. It is explanatory drawing which shows the format of the packet for content transmission in the information delivery system of this invention. It is a block diagram of the client terminal device in the information delivery system by Embodiment 2 of this invention. It is explanatory drawing which shows the content of the video packet reception buffer and the additional information packet reception buffer in the information delivery system by Embodiment 2 of this invention. It is explanatory drawing which shows the operation | movement sequence of the information delivery system by Embodiment 3 of this invention. It is a flowchart which shows operation | movement of the information delivery system by Embodiment 3 of this invention.

Explanation of symbols

  1 video content distribution device (content distribution device), 2 additional information content distribution device (additional information distribution device), 3 client terminal device, 5 transmission relative time comparator, 6 video packet reception buffer, 7 additional information packet reception buffer, 8 Buffer read control unit, 9 video decoding processing unit, 10 additional information decoding processing unit.

Claims (5)

A content distribution device for streaming any content and transmitting the transmission start time of the content;
An additional information distribution device that distributes additional information for reproduction in synchronization with the content, based on the content transmission start time transmitted from the content distribution device;
An information distribution system comprising: a client terminal device that reproduces content distributed from the content distribution device and additional information distributed from the additional information distribution device. When the content distribution device distributes the content, the content distribution device distributes the content by adding the relative transmission time of the content,
And,
When the additional information distribution device distributes the additional information, the additional information distribution device adds the relative transmission time of the additional information and distributes it,
2. The client terminal device according to claim 1, wherein the processing timing is adjusted so that the content and the additional information are synchronized based on a relative transmission time of the content and a relative transmission time of the additional information. Information distribution system. The content distribution device notifies the additional information distribution device of the transmission delay time between the content distribution device and the client terminal device,
The additional information distribution device compares the transmission delay time notified from the content distribution device with the transmission delay time between the additional information distribution device and the client terminal device, thereby determining the additional information distribution start time. The information distribution system according to claim 1 or 2, wherein adjustment is performed. If the additional information distribution device cannot distribute the additional information based on the transmission start time notified from the content distribution device, the additional information distribution device notifies the content distribution device of the desired transmission start time,
4. The information distribution system according to claim 3, wherein the content distribution apparatus resets a transmission start time in response to the information on the desired time.   The content distribution device and the additional information distribution device periodically measure the transmission delay time between the content distribution device and the client terminal device and between the additional information distribution device and the client terminal device, 5. The information distribution system according to claim 3, wherein timing for transmitting additional information in the additional information distribution apparatus is adjusted based on a measurement value.

Images