JP2003115808A - Contents distribution method, method and device for receiving digital broadcasting - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a time loss caused by a plurality of times of tuning by efficiently utilizing a band. SOLUTION: A receiver 3 is configured on a Java platform 5. In channels A, B and D, BML contents are distributed. In a channel C, VRML contents are distributed. The receiver 3 acquires a presentation engine (PE) to be utilized for the channel, afterwards, starts the PE, acquires, interprets and implements the contents of the channel. A BML browser under utilizing for the channels A, B and D is distributed through a channel E. A VRML browser to be utilized for the channel C is distributed by the same channel as contents. By separately distributing the BML browser to be utilized for the channels A, B and D, it is not necessary to repeatedly distribute the BML browser for these channels, and the band can be efficiently utilized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a content distribution method, a digital broadcast receiving method and a digital broadcast receiving apparatus which are applied to distribute multimedia contents and receive multimedia contents.

[0002]

2. Description of the Related Art In a digital broadcasting system typified by satellite broadcasting, multimedia such as still images and text information is added to the conventional video and audio services and presented to the user, which has a high added value. The service has entered the practical stage.

One of them is a data broadcasting service in BS digital broadcasting, which started its service in 2000. In this service, multimedia contents are transferred to BML (Broadcast Markup Language).
It is described in a format called ge) and broadcast in synchronization with video / audio. The receiver corresponding to the data broadcasting service of each home is provided with software for interpreting and executing the content expressed in BML, and the content distributed by this software is presented to the user. By using BML, contents such as video, audio, still images, and media such as text information can be combined to easily create contents that realize an interactive operation with a user.

[0006] FIG. 9 schematically shows an implementation of a data broadcasting service in BS digital broadcasting. Reference number 1
Indicates a broadcasting station, reference numeral 2 indicates a satellite, and reference numeral 3
Indicates the receiver. Receiver 3 from broadcasting station 1 via satellite 2
, The multimedia contents A to D using BML depending on the services of the channels A to D
Have been delivered respectively. The receiver 3 interprets the multimedia contents expressed in BML and executes the process of presenting the contents, etc., by the BML browser 4
Is provided. It should be noted that in FIG. 9, the illustration of the video and audio broadcast in synchronization with the BML content is omitted. Software that interprets and executes a specific format, such as the BML browser 4, is called a presentation engine (or PE).

Generally, in data broadcasting, it is possible to adopt a format other than BML depending on a service request. For example, WWW (Wor
HTML (Hyper Tex) widely used in the ld Wide Web
t Markup Language). Broadcasting station 1 is HTML
In order to broadcast the content produced in the above format and support the service, the receiver 3 needs to have a presentation engine that interprets and executes the content expressed in HTML. Such a form is WW
This is particularly effective when the content on W is also used in data broadcasting.

[0006] When providing a service using 3D graphics, VRML (Virtual Reality M
It is also possible to adopt the odeling Language). VR
ML is a description language for three-dimensional graphics. In order for the broadcasting station 1 to broadcast the content produced in the VRML format and to support the service, the receiver 3 is V
It is necessary to have a presentation engine that interprets and executes the content expressed in RML.

Conventionally, when it is desired to use different formats for each channel in one broadcasting system, it is necessary for the receiver 3 to implement a plurality of presentation engines. This means that the mounting cost of the receiver 3 is
It is not desirable in terms of hardware cost. In addition, it is difficult to change or expand the format or add a new format after the receiver is once sold as a product.

On the other hand, as a trend of the data broadcasting technology, it is considered that Java (registered trademark) will be adopted in the architecture of the receiver in the future. When this happens,
An arbitrary computer program described in Java language can be distributed and executed by digital broadcasting. MHP (Multimedia Home Platform), which is a data broadcasting standard being put into practical use in Europe, is an example of adopting such Java technology in a broadcasting architecture. By using this technique, it is possible to mix a plurality of presentation engines in one broadcasting system. That is, an arbitrary presentation engine may be installed as a Java application and broadcast in combination with the content. "HotJava (TM) Browser 3.0 Sun Microsystems, Inc" has been proposed as an example of an HTML browser created in Java. This is an HTM created entirely in Java
It is an L browser, and basically has the same function as an Internet Explorer (registered trademark) or Netscape (registered trademark) navigator. It can be operated on any computer with a Java environment installed, regardless of the OS.

FIG. 10 shows a form of such a data broadcasting architecture. The difference from FIG. 9 is that the receiver 3 is Ja
It is configured on the va platform 5 and Java
That is, the execution environment of the program is installed in the receiver 3. Channels A and D provide services using BML, and channel B uses HT.
We provide services using ML, and channel C
So, we provide services using VRML. Also, a presentation engine created as a Java program, that is, a BML browser, HTM
The L browser and the VRML browser are delivered in each channel in combination with the content. After acquiring the presentation engine to be used in the channel, the receiver 3 activates the presentation engine to acquire, interpret, and execute the content in the channel.

[0010]

With the configuration of FIG. 10 described above, different presentation engines can be mixed in one broadcasting system. However, when the same format is used in a plurality of channels, there is a problem that the overlapping band for broadcasting the presentation engines is wasted. Figure 1
In the example of 0, the BML browsers are duplicately broadcasted on channel A and channel D. Generally, since the number of channels of digital broadcasting is larger than that of conventional analog broadcasting, this overlap is considerably large and cannot be ignored.

Therefore, an object of the present invention is to provide a content distribution method, a digital broadcast receiving method, and a digital broadcast receiving method which can efficiently use a limited broadcast band when different presentation engines are mixed in one broadcast system. It is to provide a digital broadcast receiving device.

[0012]

In order to solve the above-mentioned problems, the invention of claim 1 is a content distribution system by digital broadcasting, which interprets the content together with the content and distributes and executes software for use. This is a content distribution method in which only the software is broadcast on another channel when the same software is used on a plurality of channels under the environment.

According to a second aspect of the present invention, in a digital broadcast receiving method for receiving contents distributed by digital broadcasting, the same software is distributed under the environment of interpreting the contents together with the software for executing and distributing and using the software. Is used on multiple channels, only the software is broadcast on a different channel, the transport stream containing the different channels is tuned to obtain the software, and the selected service and that software are identical. Whether it is included in the transport stream is determined, and when it is determined that it is included in the same transport stream, the content is acquired from the transport stream and it is determined that the content is not included in the same transport stream. If the content is Tuning the transport stream including a digital broadcast receiving method for obtaining the content. The invention of claim 6 is the receiving apparatus for acquiring the content as described above.

According to a fourth aspect of the present invention, in the digital broadcast receiving method for receiving the content distributed by digital broadcasting, the same software is distributed under the environment in which the software that interprets the content and executes the software is distributed and used. When is used on multiple channels, only the software will be broadcast on another channel, one or more software will be saved in advance, and if a new channel is selected, the software to be used on that channel, Judge whether the software stored in the memory matches, if it matches, tune the transport stream including the channel of the content, use the stored software, and if it does not match, Transport store including channels Tuning the system, acquiring the software, determining whether the selected service and the software are included in the same transport stream, and determining that they are included in the same transport stream. A digital broadcast receiving method in which content is acquired from the transport stream, and when it is determined that the content is not included in the same transport stream, the transport stream including the content is tuned to acquire the content.
The invention of claim 8 is the receiving apparatus for acquiring the content as described above.

In a digital broadcasting system in which a plurality of presentation engines are mixed, the presentation engines used in a plurality of channels are distributed by independent channels different from the content, so that the bandwidth available to the broadcasting system is effectively used. it can. Also, by preparing a buffer for the presentation engine, it is possible to compensate for the time loss caused by tuning multiple times.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to FIG. In one embodiment, the broadcast signal is transmitted from the broadcast station 1 to the receiver 3 via the satellite 2. The receiver 3 is configured on the Java platform 5, and the receiver 3 includes a Java program execution environment. Also channels A, B and D
So, we are providing services using BML.
The L content A, the BML content B, and the BML content C are distributed. Channel C provides a service using VRML, and VRML content is distributed.

Also, the presentation engine and contents created as Java programs are distributed. After acquiring the presentation engine to be used in the channel, the receiver 3 activates the presentation engine to acquire, interpret, and execute the content in the channel. In this case, the presentation engine used in a plurality of channels is delivered in a channel different from the content. In FIG. 1, since the BML browser is used in the channels A, B and D, the BML browser is distributed via the channel E which is independent of the content. The VRML browser used only on the channel C is distributed on the same channel C as the content. By separately distributing the BML browsers used in the channels A, B, and D, it is not necessary to redundantly distribute the BML browsers in these channels, and the broadcasting system can efficiently use the band. That is, in one embodiment, the bandwidth of two browsers can be saved.

Here, in order to facilitate understanding of the embodiment, a channel selection process in the receiver in the conventional broadcasting system will be described. Digital broadcasting is generally composed of a set of broadcast waves called a transport stream. The transport stream is further divided into a logical state transmission path called an elementary stream (hereinafter appropriately referred to as ES) and handled.

Each elementary stream has a unique PI.
It has D (integer value indicating ID), and one or a plurality of elementary streams form one channel.
Therefore, selecting a channel is nothing but extracting each elementary stream that constitutes that channel. In order to extract, it is necessary to have information about which transport stream the channel is included in, and what number and in which elementary stream the transport stream is composed of. PSI (Program Specific Information) holds this information. P
SI is also a type of elementary stream. There are several types of PSI, but regarding channel selection processing, NIT (Network Information Table), P
AT (Program Association Table), PMT (Program Ma
p Table) is relevant.

There is one PMT for each channel,
P of the elementary streams that compose the channel
Holds the ID. There is one PAT for each transport stream and holds the PID of the PMT of the channel included in the transport stream. Therefore, the content of the PAT is unique to each transport stream. Further, the NIT is included in every transport stream one by one, and holds all channel numbers included in the broadcasting system and information regarding which transport stream it is included in. NIT
The content of is common to each transport stream.

FIG. 2 shows the transport stream and NI.
The relationship of T is shown typically. The example of the broadcasting system shown in FIG. 2 is composed of five transport streams, and each contains a NIT having common contents. Each transport stream includes multiple channels. For example, the transport stream 2 includes channels 110, 125, and 138.

FIG. 3 schematically shows the structure of a certain transport stream, for example, the transport stream 2. The transport stream contains PA with unique contents.
Reference of PMT that contains one T and holds the contents of each channel included in the transport stream (PID)
Hold. The PMT holds a reference (PID) to each elementary stream that constitutes the service of that channel. In the example of FIG. 3, a PMT stream, a content stream, and a presentation engine stream are shown for the channel 110, but other media streams such as video and audio are handled in the same manner. The content has a format such as BML and HTML, and is interpreted and executed by the presentation engine. The elementary stream is packetized and time-division multiplexed to form a transport stream.

FIG. 4 is a flowchart showing the process of selecting an arbitrary channel in the conventional receiver in such a broadcasting system. In the first step S1, the NI included in any transport stream is
Get T. In step S2, which transport stream includes the selected channel based on the NIT is determined, and switching is performed so as to receive the transport stream including the channel.
If the desired transport stream is different from the current transport stream, the transport stream is switched. Hereinafter, such processing will be appropriately referred to as tuning.

In step S3, the PAT in the transport stream is acquired. The PID of the channel is acquired from the PAT, and thereby the PMT is acquired (step S4). A target stream, that is, a presentation engine stream and a content stream are extracted by the PID information of each elementary stream described in the PMT. In the example of FIG. 4, the presentation engine PE is acquired (step S5), and the desired content is acquired in step S6.

In one embodiment of the present invention, as described above, another channel for transmitting only the presentation engine used in a plurality of channels is provided. The process of receiving an arbitrary channel in one embodiment is shown in the flowchart of FIG. In the first step S11, the NIT included in any transport stream is acquired. In step S12,
Based on the NIT, which transport stream the channel of the desired PE (Presentation Engine) is included in is determined, and the transport stream including the channel is tuned.

In step S13, the PAT in the transport stream is acquired. The PID of the channel is acquired from the PAT, and thereby the PMT is acquired (step S14). Based on the PID information of each elementary stream described in the PMT, the desired P
E is acquired (step S15).

In step S16, it is determined whether the selected service and the PE used by the service are the same transport stream. When it is determined that they are the same transport stream, step S
17, PM of the channel containing the content
T is acquired. Then, in step S18, the content is acquired.

When it is determined in step S16 that the PE and the content are not the same transport stream, the transport stream including the channel of the content is tuned in step S19. The PAT in the transport stream is acquired (step S20). After that, step S17
And the contents are acquired by going through S18.

As described above, in one embodiment of the present invention, first, the channel of the presentation engine corresponding to the format of the content is extracted to obtain the presentation engine, and then the channel of the content is extracted to extract the content. get.

In one embodiment of the invention, the NIT needs to be extended. FIG. 6 shows a format of a service list descriptor which is a part of NIT. "service list de
scriptor () {} "indicates that the content in {} is the format of the service list descriptor. Within {}, the name (field) of the data that appears concretely in the list is shown. They are listed in the order in which they appear, "for (i = 0; i <
"N; i ++)" means that the contents of {} are repeated N times.

The contents of the field will be described. "des
criptor "tag" is a unique ID value that indicates that the content that follows is a service list descriptor. lengt
"h" indicates the byte length of the service list descriptor.
ce "id" indicates an ID value for uniquely identifying the service. "type" represents the type of service.

For the extension of NIT, "engine type "
(8 bit) and "engine "version" (8 bits) is defined. The type of presentation engine used by the channel can be determined by these pieces of information.

The table shown in FIG. 7 shows the type of service and the type of service format (ID value). Service format type is "service Used in the "type" field. 0x
Means hexadecimal display. For example, 0x01 indicates a digital television service. In this one embodiment, 0xC1
Is defined as the presentation engine. This extension can determine that the channel is for delivering a particular presentation engine.

Next, another embodiment of the present invention will be described. The above-described embodiment includes the selected service,
If the presentation engine used by the service is not on the same channel, it is necessary to perform tuning twice. Since tuning cannot be performed only by software processing, there is a problem that it takes time. In another embodiment, in order to solve this problem, the receiver is provided with a buffer memory for a presentation engine.

FIG. 8 shows a process for receiving an arbitrary channel in another embodiment. The receiver stores the most recently received presentation engine in a non-volatile memory or a hard disk (hereinafter referred to as a buffer) in the receiver. The number of presentation engines to be saved is arbitrary.

In the first step S31, the NIT included in any transport stream is acquired. That is, when a new channel is selected, information about the type and version of the presentation engine used in the channel is displayed as "engine" in FIG. type "and"
engine It is acquired from the field of "version". In step S32, it is determined whether or not the presentation engine exists in the buffer.

If there is a presentation engine of the same type and version as the present presentation engine in the buffer, in step S33,
Tune the transport stream containing the content channel. The PAT in the transport stream is acquired (step S34). Then, in step S35, the PMT of the channel including the content is acquired. And step S3
At 6, the content is acquired. In this way, by using the presentation engine held in the buffer, it is not necessary to acquire the presentation engine from the broadcast wave again, and it is possible to prevent time loss.

If the result of step S32 is negative, it is necessary to acquire the presentation engine from the broadcast wave, and the processes of step S37 and subsequent steps are performed, as in the one embodiment. In step S37, the transport stream including the desired PE (presentation engine) channel is tuned, and in step S38, the PAT in the transport stream is acquired. In step S39, the PID of the channel is acquired from the PAT, and thereby the PMT is acquired. P
PI of each elementary stream described in MT
A desired PE is acquired from the D information (step S4).
0).

In step S41, it is determined whether the selected service and the PEs used by the service are the same transport stream. If it is determined that they are the same transport stream, in step 35, the content The PMT of the channel including is acquired, and the content is acquired in step S36. When it is determined in step S41 that the PE and the content are not the same transport stream,
In step S33, the transport stream including the channel of the content is tuned, and the PAT in the transport stream is acquired (step S34). After that, steps S35 and S3
The content is acquired by going through 6.

The present invention is not limited to the above-described embodiment of the present invention and the like, and various modifications and applications are possible without departing from the gist of the present invention. For example, a presentation engine used in a single channel may be distributed by a channel dedicated to the presentation engine, or a plurality of channels dedicated to the presentation engine may exist. Further, a receiver having no buffer in one embodiment and a receiver having a buffer in another embodiment can be mixedly provided in the same broadcasting system.

[0041]

According to the present invention, in a data broadcasting system in which a plurality of presentation engines are mixedly broadcast, the presentation system used in a plurality of channels is distributed in another channel independent of the content to thereby realize a broadcasting system. The band that can be used by can be efficiently used. Also, like other embodiments,
If you provide a buffer for the presentation engine,
It is possible to compensate for the time loss caused by tuning multiple times.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a form of a data broadcasting system according to the present invention.

FIG. 2 is a schematic diagram schematically showing an example of a transport stream.

[Fig. 3] Fig. 3 is a schematic diagram schematically illustrating a configuration example of a transport stream.

FIG. 4 is a flowchart showing a conventional process of selecting an arbitrary channel.

FIG. 5 is a flowchart showing a process of selecting an arbitrary channel according to the embodiment of the present invention.

FIG. 6 is a schematic diagram used for explaining expansion of NIT according to an embodiment of the present invention.

FIG. 7 is a schematic diagram used for explaining expansion of NIT according to an embodiment of the present invention.

FIG. 8 is a flowchart showing a process of selecting an arbitrary channel according to another embodiment of the present invention.

FIG. 9 is a schematic diagram showing a form of conventional data broadcasting.

FIG. 10 is a schematic diagram showing a form of data broadcasting when Java technology is adopted.

[Explanation of symbols]

1 ... Broadcasting station, 3 ... Receiver, 5 ... Java platform

Claims (9)

[Claims] 1. In a content distribution system by digital broadcasting, when the same software is used in a plurality of channels under an environment in which software for interpreting and executing the content together with the content is distributed and used, A content distribution method that broadcasts only software on another channel. 2. A digital broadcast receiving method for receiving contents distributed by digital broadcasting, wherein the same software is used in a plurality of channels under an environment in which software for interpreting and executing the contents together with the contents is distributed and used. When used in, only the above software is broadcast on another channel, the transport stream including the above other channel is tuned, the above software is acquired, and the selected service and that software are the same transport. Whether it is included in the port stream is determined, and when it is determined that it is included in the same transport stream, the content is acquired from the transport stream and it is determined that the content is not included in the same transport stream. In case, content Digital broadcast receiving method for acquiring content by tuning the transport stream including a. 3. The digital broadcast receiving method according to claim 2, wherein the Java platform is adopted. 4. A digital broadcast receiving method for receiving contents distributed by digital broadcasting, wherein the same software is used in a plurality of channels under an environment in which software for interpreting and executing the contents together with the contents is distributed and used. When used in, only the above software will be broadcast on another channel, if one or more of the above software is saved in advance and a new channel is selected, the above software to be used on that channel and the above Judge whether the above software stored in the memory matches or not, and if it matches, tune the transport stream including the channel of the content, use the above stored software, and if it does not match, , Including another channel above When the transport stream is tuned, the software is acquired, it is determined whether the selected service and the software are included in the same transport stream, and it is determined that they are included in the same transport stream. Then, a digital broadcast receiving method of acquiring content from the transport stream, and tuning the transport stream including the content to acquire the content when it is determined that the content is not included in the same transport stream. 5. The digital broadcast receiving method according to claim 4, wherein the Java platform is adopted. 6. In a digital broadcast receiving apparatus for receiving content distributed by digital broadcasting, the same software as described above is used in a plurality of channels under an environment in which software for interpreting and executing the content together with the content is distributed and used. When used in, only the above software is broadcast on another channel, the transport stream including the above other channel is tuned, the above software is acquired, and the selected service and that software are the same transport. Whether it is included in the port stream is determined, and when it is determined that it is included in the same transport stream, the content is acquired from the transport stream and it is determined that the content is not included in the same transport stream. In case, content Digital broadcast reception device for obtaining content by tuning the transport stream including a. 7. The digital broadcast receiving apparatus according to claim 6, which employs a Java platform. 8. In a digital broadcast receiving apparatus for receiving contents distributed by digital broadcasting, the same software as described above is used in a plurality of channels under an environment where software for interpreting and executing the contents together with the contents is distributed and used. When used in, only the above software will be broadcast on another channel, if one or more of the above software is stored in memory in advance and a new channel is selected, the software to be used on that channel, It is determined whether the software stored in the above memory matches, and if there is a match, tune the transport stream including the channel of the content, use the above stored software, and if there is no match, , Including another channel above When the transport stream is tuned, the software is acquired, it is determined whether the selected service and the software are included in the same transport stream, and it is determined that they are included in the same transport stream. Then, a digital broadcast receiving apparatus that acquires content from the transport stream and, when it is determined that the content is not included in the same transport stream, tunes the transport stream including the content to acquire the content. 9. The digital broadcast receiving apparatus according to claim 8, which employs a Java platform.