WO2006079936A1

WO2006079936A1 - Method and apparatus of digital program broadcasting, recording and playback

Info

Publication number: WO2006079936A1
Application number: PCT/IB2006/050137
Authority: WO
Inventors: Jun Shi; Jingwei Tan; Declan Patrick Kelly; Liang Gan
Original assignee: Koninklijke Philips Electronics N.V.
Priority date: 2005-01-25
Filing date: 2006-01-16
Publication date: 2006-08-03
Also published as: JP2008529332A

Abstract

The present application provides a method of creating a link identifier in a digital program, including the steps of: confirming that the digital program is associated with link information; and integrating a corresponding link identifier into the digital program, wherein the link identifier indicates that the digital program is associated with link information. According to a method or apparatus of the present invention, with the link identifier created in the digital program, it is able to notify the recording apparatus that the recorded digital program will involve the Internet access, and enable the recording apparatus to record necessary information needed for accessing the Internet, e.g. link information, even to record the linked network data together with an interactive program.

Description

METHOD AND APPARATUS OF DIGITAL PROGRAM BROADCASTING,

RECORDING AND PLAYBACK

FIELD OF THE INVENTION

The present invention relates to digital program broadcasting, recording and playback, and more particularly, to interactive TV program broadcasting, recording and playback.

BACKGROUND OF THE INVENTION

TV program broadcasting is a conventional way for a user to obtain information. With the development of IP technology, the Internet has become another important way for people to get information. The Internet service can provide the user with textual information, graphics information, audiovisual information and other various kinds of information. Under the broadcasting mode, a broadcaster delivers program content to the user in a "push" manner. Under the Internet service mode, the user can obtain information from the Internet server on his own initiative, and such a manner is called "pull". The development of digital TV broadcasting brings about new prospects for combining the broadcasting service with the Internet service.

Digital interactive TV (iTV) program includes not only audiovisual content but also interactive applications. Some interactive applications have the ability to access the Internet or get data through an IP connection. The set top box (STB) with storage or an interactive TV recorder can record the iTV program to the storage medium, which is a hard disc or optical disc such as DVD + RW or Blu-ray disc. Recorders can record the iTV program directly without playing them back.

The Internet service provides the user with personalization and enables the user to select to watch content of interest. This is a feature distinct from broadcasting. The broadcasting company can charge for providing some extra Internet services or use these services to attract clients.

One example of the IP data application by the broadcasting company is a multi-angle program. For example, there are multi-angle programs in a football match. For a certain exciting episode of shooting, the user may hope to watch it from different angles, and usually there are multiple cameras in the pitch tracking the entire match. However, to simultaneously broadcast all programs from different angles will sharply increase costs because of the problem of utilization ratio of bandwidth. Besides, some users might hope to watch from multiple angles, while others hope not. A good method for solving this problem is to broadcast a main angle from the broadcasting channel and place other angles on the Internet server so that the user can watch these angles when they need to. The broadcasting company can charge for this service or use this feature to attract users. The interactive program will decide the display of these angles, which will be displayed in a picture-in-picture fashion or in a full- screen fashion.

To record a TV program is an ordinary demand of the user. The user hopes to record a digital TV program using a personal digital recorder just as he records an analog TV program using a recorder. When the user watches a TV program and finds it interesting, the user hopes that he can record the TV program. For an interactive TV program that can access the Internet, the Internet access commands are usually initiated by the interactive application. For example, an application can access the Internet server to get some image files from the server for display. However, in all the currently existing systems providing various kinds of interactive TV programs, the recorder does not know the iTV program will access the Internet. Therefore, the recorder will not record the network content data. The network content directed by the Internet link provided together with the iTV program usually will not be available anymore some time after the live broadcast. If the recorder does not record the network content data during the live broadcast, then the recorded iTV program may not be played normally according to the user's expectation.

Therefore, there is a need for a method and apparatus, which are capable of notifying a receiver, a recorder in particular, that an interactive TV program will involve the Internet access, and enabling the receiver to easily keep information necessary for the Internet access and Internet data content used by the program.

OBJECT AND SUMMARY OF THE INVENTION

It is an object of the present invention to notify a recording apparatus of an interactive TV program that the recorded interactive TV program will involve the Internet access, and enable the recording apparatus to record Internet data content used by the program together with the interactive TV program.

The present invention provides a method of creating a link identifier in a digital program, including the steps of: confirming that the digital program is associated with link information; and integrating a corresponding link identifier into the digital program, wherein the link identifier indicates that the digital program is associated with link information.

The present invention further provides an apparatus of creating a link identifier in a digital program, comprising: confirming means for confirming that the digital program is associated with link information; and integrating means for integrating a corresponding link identifier into the digital program, wherein the link identifier indicates that the digital program is associated with link information.

The present invention further provides a method of recording a digital program, including the steps of: (a) receiving a digital program which contains a link identifier for indicating that the digital program is associated with link information; (b) recording the digital program; (c) acquiring the corresponding link information in accordance with the link identifier; and (d) recording network data corresponding to the link information.

The present invention further provides an apparatus of recording a digital program, comprising: receiving means for receiving a digital program which contains a link identifier for indicating that the digital program is associated with link information; acquiring means for acquiring the corresponding link information in accordance with the link identifier; and recording means for recording network data corresponding to the link information, and the digital program.

The present invention further provides a method of playing back a digital program, including the steps of: playing back a digital program that is associated with link information; and playing back network data pre-stored in a local area, when network data corresponding to the link information needs to be played back.

The present invention even further provides an apparatus of playing back a digital program, comprising: playback means for playing back a digital program that is associated with link information; and network data acquiring means for acquiring network data pre-stored in a local area, when network data corresponding to the link information needs to be played back.

According to a method or apparatus of the present invention, with a link identifier created in a digital program, it is able to notify the recording apparatus that the recorded digital program will involve the Internet access, and enable the recording apparatus to record necessary information needed for accessing the Internet, e.g. link information, even to record the linked network data together with an interactive program. Such a recording process can be initiated without participation of the user.

According to a method or apparatus of the present invention, it is able to download a received digital program and/or network data involved in the digital program to a personal computer, so that the network data can be reproduced better.

Other objects and advantages of the present invention will become apparent, and the present invention will be appreciated more comprehensively from the following description, taken in conjunction with the accompanying drawings, and the claims. BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention will be described in detail with reference to the accompanying drawings, in which:

Fig. 1 is a flow chart illustrating a method of creating a link identifier in a digital program according to an embodiment of the present invention;

Fig. 2 is a flow chart illustrating a method of recording a digital program according to an embodiment of the present invention;

Fig. 3 is a flow chart illustrating a method of playing a digital program according to an embodiment of the present invention;

Fig. 4 is a schematic block diagram showing an apparatus of creating a link identifier in a digital program according to an embodiment of the present invention;

Fig. 5 is a schematic block diagram showing an apparatus of recording a digital program according to an embodiment of the present invention; and

Fig. 6 is a schematic block diagram showing an apparatus of playing a digital program according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to the preferred embodiments of the present invention.

Fig. 1 is a flow chart illustrating a method of creating a link identifier in a digital program according to an embodiment of the present invention.

As shown in Fig. 1, in step SIlO, confirm that a digital program is associated with link information. Here, the digital program may be an interactive TV program for instance, or a program of other type. The different types of the digital program are not limitations on the present invention. Basic contents of the link information are URLs (Uniform Resource Locator) to be accessed by applications in the digital program, authorization information and the like. For example,

<URL> http: //www.philips.com/video/brand.wmv </URL>

<Name> userl </Name>

</Authorization>

Step SIlO may include a step of receiving an instruction for example, the received instruction containing information related to a link identifier. The link identifier is used to indicate that the digital program is associated with link information. After the instruction is received, it is confirmed that the digital program is associated with link information. The instruction may be, for example, inputs from the producing personnel of the digital program. For instance, the producing personnel of the digital program may input a file, and the name of the file may employ the following format: dvb.IP.oooooooo.aaaa wherein "oooooooo" is the organization identifier of the application as an 8 character hexadecimal string, and "aaaa" is the identifier of the application as a 4 character hexadecimal string.

It can be agreed that, if the file name in the aforesaid format is detected to be input, that the digital program is associated with link information can be confirmed.

In addition, it can also be detected whether a specific button is pressed. For instance, it can be provided that the digital program personnel can show the digital program is associated with link information by pressing a specific button.

Of course, whether the digital program is associated with link information can be confirmed by parsing the digital program automatically. Then, in the step S 120, integrate the link identifier into the digital program. In view of the different types of link information, various ways can be adopted to integrate the link identifier into the digital program, which will be described in detail.

Then, in step S 130, transmit the digital program, that is, the digital program integrated with the link identifier, to the transmission medium. The transmission medium could be, for example, a satellite network, a fixed-line network or a cable TV network.

Hereinafter, several types of link identifier will be described together with ways to integrate the link identifier into the digital program.

First type of link identifier

For instance, link information to be involved can be stored in a predefined link information descriptor that is a first type of link identifier in the present embodiment. The descriptor is predefined in a service information section of the digital program transmission stream. By predefining such a descriptor in a service information section of the digital program transmission stream, the step of integrating the link identifier into the digital program can be performed conveniently. Here, the service information section may be PMT (Program Mapping Table) provided by MPEG-2, AIT (Application Information Table) provided in MHP (Multimedia Home Platform) and so on.

The PMT' s architecture is as shown in Table 1. Table 1

As shown in Table 1, N descriptors for the entire program and N2 descriptors for a specific essential stream (ES) can be defined in the PMT section. The AIT' s architecture is as shown in Table 2. Table 2

As shown in Fig. 2, M descriptors for the entire program and M2 descriptors for a specific application can be defined in the AIT section.

As is clear from Fig. 2, there are two classes of descriptors in the AIT section, namely common descriptor appearing in the common loop and application descriptor appearing in the application loop. The common descriptor is applicable to the entire digital program, while the application descriptor is applicable to a specific application.

Besides PMT and AIT, descriptors in other service information sections of the digital program transmission stream can be used as link identifiers to transfer link information.

In the present embodiment, such a descriptor for transferring link information is called "link information descriptor". For instance, the link information descriptor can be defined as shown in Table 3.

Table 3

The Linklnfo field in Table 3 can include, for instance, the following information: <URL> http://www.philips.com/video/brand.wmv </URL> <Authorization> <Name> userl </Name> <Code> T3r6ygHt </Code> </Authorization>

Linklnfo in Table 3 can also be omitted. In such a case, the descriptor in Table 3 will only be used to indicate that the digital program is associated with link information. The associated link information can be placed in other locations in the digital program transmission stream, for instance, in an application per se. If the associated link information is placed in the application per se, then the terminal can acquire the associated link information by opening the application.

Second type of link identifier

Of course, link information can also be stored in a file. The file that stores the link information is called "link information file". The link information file is the second type of link identifier in the present embodiment. A link information file may store information on a plurality of links. For example, the link information file may include the following contents:

1. <!Link information file>

2. <Link>

<URL> http://www.philips.com/video/brand.wmv </URL>

<Name> userl </Name>

</Authorization>

<Redirect_type> 1 </Redirect_type>

3. </Link>

4. <Link>

<URL> http://www.philips.com/audio/brand.mp3 </URL>

<Name> userl </Name>

</Authorization>

<Redirect_type> 1 </Redirect_type>

5. </Link>

6. ...

The link information file can adopt XML-based syntax. And protocol information and other information can be stored in the link information file.

The name of the link information file may be "dvb.IP.oooooooo.aaaa", wherein "oooooooo" is the organization identifier of the application as an 8 character hexadecimal string, and "aaaa" is the identifier of the application as a 4 character hexadecimal string.

All the link information can be included in one link information file, or the link information can separately be stored in different link information files according to needs. Afterwards, the link information file is multiplexed into the digital program transmission stream and transmitted to the terminal together with the digital program (containing the application). With this multiplexing process, the step of integrating the link identifier into the digital program is performed. And through negotiation between the broadcasting front end and terminal, the terminal acquires the link information file by demultiplexing the digital program transmission stream.

Third type of link identifier

The third type of link identifier is a combination of a descriptor and a link information file. Such a descriptor can be called "IP connection descriptor". For instance, IP connection descriptor can be defined as shown in Table 4.

Table 4

The value of the "Type" field in Table 4 can be 0 or 1. Type=l means that the digital program transmission stream includes the link information file, while Type=0 means that the digital program transmission stream includes no link information file.

Thus, when broadcasting the digital program, the Type field in the IP connection descriptor is set as 1 only where the digital program transmission stream multiplexes the link information file. Therefore, the terminal de-multiplexes the link information file from the digital program transmission stream only where it has detected that the Type field in the IP connection descriptor in the corresponding service information section is 1. The terminal does not need to detect as always whether the link information file appears in the received digital program transmission stream. Instead, only by parsing service information of the digital program transmission stream once, can the terminal know whether the received digital program transmission stream contains the link information file. As a result, the working efficiency is enhanced.

Fourth type of link identifier

The fourth type of link identifier is a combination of an IP connection descriptor, a link information descriptor and a link information file. For instance, for the entire digital program, an IP connection descriptor is defined for indicating whether the digital transmission stream multiplexes the link information file. For each application in the digital program, a link information descriptor is defined, respectively, for indicating the file name of a link information file corresponding to the application, e.g. as shown in Table 5: Table 5

The "Info_filepath" field in Table 5 is used to indicate the file name of the corresponding link information file. The alternative is that all the link information files can be stored in a fixed directory (e.g. root directory), so that the "Info_filepath" field in Table 5 can be omitted. Of course, through negotiation between the broadcasting front end and the terminal over the link information file name and file path, the "Info_filepath" field in Table 5 can also be omitted.

And then, for each application of the digital program, a link information file is prepared, respectively, and these link information files are inserted into the digital program transmission stream.

The above-mentioned four types of link identifier are just illustrative. Those skilled in the art can conceive other types of link identifier. And the different types of link identifier do not form limitations on the present invention.

In various links, some links can be redirected, while some cannot. For instance, an MPS file can be played back by the STB (Set Top Box) and the PC (Personal Computer), whereas an MHP application coming from the Internet can only be played back by the STB that has an MHP middleware, rather than by the PC.

Therefore, a redirect identifier can be set in the above-described link information descriptor or link information file, namely <Redirect_type> tag, for indicating that the corresponding link information can be redirected. For instance, <Redirect_type> tag may be:

<Redirect_type> 1 </Redirect_type>

Where the value of <Redirect_type> tag is 1, it means that the link can be redirected, i.e., can be used by other apparatus. For instance, the terminal can redirect the link information to the PC (Personal Computer) and request the PC to download and store the linked content. Where the value of <Redirect_type> tag is 0, it means that the link cannot be redirected, i.e., can only be used by the terminal.

Regarding how to multiplex (integrate) the link information file to the digital program transmission stream, for MPEG-2 transmission stream, it can insert the link information file into the transmission stream via DSM-CC Protocol.

It is to be understood by those skilled in the art that, the different ways to integrate link identifier into the digital program transmission stream and the different protocols adopted are not limitations on the present invention.

Fig. 2 is a flow chart illustrating a method of recording a digital program according to an embodiment of the present invention.

As shown in Fig. 2, in step S210, receive a digital program transmission stream from a transmission medium. Here, the digital program is an interactive TV program, or a program of other type of course. The different types of the digital program are not limitations on the present invention. In step S220, identify a link identifier in the digital program transmission stream. The link identifier may be a link identifier of each of the types as described with reference to Fig.1 in the foregoing. In step S230, acquire the corresponding link information in accordance with the link identifier. The link information may include, for example, one or more of the link information descriptor, IP connection description and link information file. The front end and the terminal of the broadcasting may pre-determine the concrete transferring manner of the link information, and then perform operations correspondingly. Details thereof will be omitted here.

In step S240, acquire network data corresponding to the link information from the Internet. In step S250, generate a map file indicating the relation between the network data and the link information. Then, in step S260, record the digital program received in step S201, the network data acquired in step S240 and the map file generated in step S250. The received digital program, the acquired network data and the generated map file can be recorded in one identical apparatus (e.g. a personal digital recorder, or the set top box with storage), or in different apparatuses (e.g. the personal computer).

For instance, if the value of the detected <Redirect_type> tag is 1, then the network data acquired in step S240 can be transmitted to a personal computer and stored in the personal computer.

It is alternative that, if it is detected that the link identifier identified in step S220 only contains <Redirect_type> tag and the value of <Redirect_type> tag is 1, then the link information acquired in step S230 can be transmitted to a personal computer, and the personal computer is demanded to download and record network data corresponding to the link information.

The instruction on a personal computer to perform the corresponding downloading process is based on such considerations. Sometimes, web browsing is not consistent with the activity of watching such a digital program as interactive TV. Some web pages are not displayed good enough on TV, and some TVs will even not support the latest web formats. However, broadcasters are always trying to provide supplemental information via an interactive TV program and draw viewers to specific web sites. For instance, broadcasters can insert graphics or text (not the actual URLs) into the interactive TV program and provide them to viewers along with the transmission stream. Viewers can select to watch or download web page contents (hereinbefore referred to as "network data") linked with theses graphics or text. Some web page contents (e.g. "flash" file) cannot be played on the TV. Therefore, the user can select to download these web page contents to an apparatus (e.g. a personal computer) suitable for playing back these contents so as to view them later. When watching the interactive TV program, viewers might be too lazy to open the PC or might not have time to open the PC, so the broadcasted web page contents are not downloaded. However, according to the method as illustrated in Fig. 2, network data needs to be downloaded to the PC can be downloaded automatically during watching the interactive TV program. If the linked object is an actual content, then the actual content can completely be downloaded to the PC. If the linked object is a web page, then a bookmark directing this web page can be added to the PC's browser so that the user can see the latest version of the web page at all time.

Fig. 3 is a flow chart illustrating a method of playing back a digital program according to an embodiment of the present invention.

As shown in Fig. 3, in step S310, play back a digital program. As described in the foregoing, the digital program may be an interactive TV program, and may be provided with one or more applications. The application of the digital program is related to network connection. That is to say, the digital program is associated with link information.

In step S320, operate the application in the digital program.

In step S330, judge whether or not the application needs to acquire the network data.

If the judgment result of step S330 is positive, the process proceeds to step S340; otherwise, the process proceeds to step S360.

In step S340, search a map file stored in the local area to acquire the correspondence relation between the network connection the application needs to establish, and the network data stored in the local area or network data needs to be downloaded from the Internet. In step S350, acquire the network data from the local area or the Internet on the basis of the correspondence relation acquired in step S340, and the acquired network data is reproduced.

In step S360, judge whether or not to end the digital program played back.

If the judgment result of step S360 is negative, then the process goes back to step S330; otherwise, the process is finished.

The aforesaid step S340 is optional.

The aforesaid step S320 is also optional. The network data stored in the local area can be reproduced directly.

In order to use network data stored in the local area together with the digital program, a proxy will be set up in the playback apparatus. When the digital program stored in the local area is played back and the application begins to get network data, the proxy will determine whether to get the relevant network data from the Internet or from local storage by parsing the "map file" stored in the local area.

During live broadcasting, the interactive applicant will read the linked content from the Internet through the Internet connection. When the storage has embed-linked digital program and begins to play back the digital program from the local storage, the applicant will try to be connected to the Internet. Therefore, when storing the application, the application code shall be revised, or the playing apparatus (e.g. player) must redirect the application so as to get network data from the local storage. However, to revise the application when storing it is not a feasible solution. It is because the recording apparatus (e.g. video recorder) must parse all the application codes, which is not suitable for real-time recording; besides, if the application and the transmission stream are not separately stored, then the revised application even needs to be multiplexed to the transmission stream once again.

In actual situations, some link contents can be stored in the local area, while some can be obtained from the Internet.

Fig. 4 is a schematic block diagram showing an apparatus of creating a link identifier in a digital program according to an embodiment of the present invention. In Fig. 4, numeral 400 denotes a broadcasting front end in the present embodiment; numeral 410 denotes an apparatus of creating a link identifier in a digital program, which may be a transmission stream multiplexer; numeral 420 denotes a transmitter; numeral 430 denotes a satellite/fixed/cable network; numeral 440 denotes a terminal; numeral 450 denotes receiving unit; numeral 460 denotes confirming unit; and numeral 470 denotes integrating unit.

As shown in Fig. 4, the transmission stream multiplexer 410, in addition to having the function of the prior transmission stream multiplexer, is further used to integrate the link identifier indicating that the digital program is associated with link information into the digital program transmission stream. The concrete integrating manner is just as described in the foregoing with reference to Fig.l and hence, will be omitted.

The confirming unit 460 is used to confirm that the digital program is associated with link information. In one carrying-out mode, the confirming unit 460 may comprise receiving unit 450. The receiving unit 450 is used to receive an instruction that includes information related to the link identifier. For the link identifier and the link information, please see the description about Fig. 1 in the foregoing.

The transmitter 420 is used to transmit the digital program transmission stream to a transmission medium, such as satellite/fixed/cable network 430, so as to be broadcasted to the terminal 440.

Referring to the description about Fig. 1 in the foregoing, the transmission stream multiplexer 410 can insert the link information into the descriptor in a service information section of the transmission stream, or into the link information file that is multiplexed to the transmission stream. The descriptor can be used in conjunction with the link information file so as to transfer the link information.

Fig. 5 is a schematic block diagram showing an apparatus of recording a digital program according to an embodiment of the present invention. Numeral 500 denotes an apparatus of recording a digital program in the present embodiment; numeral 510 denotes receiving unit; numeral 520 denotes acquiring unit; numeral 530 denotes downloading unit; numeral 540 denotes recording unit; numeral 550 denotes nonvolatile storage; numeral 560 denotes the Internet; numeral 570 denotes a PC; numeral denotes map file generating unit; and numeral 590 denotes redirecting unit.

As shown in Fig. 5, the receiving unit 510 receives the digital program transmission stream from the transmission medium. For instance, the receiving unit 510 may comprise high frequency and other relevant circuit or element. The received digital program contains a link identifier for indicating that the digital program is associated with link information.

The audio/video stream acquired from the receiving unit 510 can directly be input into the recording unit 540 so as to be recorded into the nonvolatile storage 550.

The acquiring unit 520 can de-multiplex the digital program transmission stream received by the receiving unit 510 so as to acquire the link identifier in the digital program and get the corresponding link information on the basis of the link identifier. The link information can be acquired from the descriptor in a service information section of the digital program transmission stream or from the link information file multiplexed from the digital program transmission stream. For how to identify the link information from the digital program transmission stream, please see the description about Fig. 2 in the foregoing and hence, it is not necessary to go into details here.

The link information acquired from the acquiring unit 520 can be input into the downloading unit 530.

The downloading unit 530 is used to acquire network data corresponding to the link information. And during acquiring the network data, the downloading unit needs to set up connection with the Internet 560.

If the link identifier contains a redirecting identifier, then the acquiring unit 520 will transmit the link information to the redirecting unit 590. Then, the redirecting unit 590 sends the link information to another different apparatus, e.g. the PC 570, and demands the PC 570 to record (i.e., download) the network data corresponding to the link information. In the process of downloading, the PC 570 needs to set up connection with the Internet 560.

The recording unit 540 stores the network data acquired by the downloading unit 530 and the digital program (such as audio/video stream and the like) acquired from the acquiring unit 520. The recording unit 540 may be, for example, hard disc reading-writing unit, tape recording unit, a DVD recorder, etc.. And the nonvolatile storage 550 may be, for example, a hard disc, a magnetic disc, an optical disc, a semiconductor chip, etc.

It is alternative that the recording unit 540 may further be an application output from the acquiring unit 520. Moreover, the recording unit 540 may also be the link information (e.g. link information file) obtained by the acquiring unit 520 from the digital program transmission stream.

Generating unit 580 can generate a map file in conjunction with the process where the downloading unit 530 obtains the network data from the Internet 560. In the map file, there is stored the correspondence relation between the obtained network data and the relevant link information. The map file could be recorded by the recording unit 540 to the nonvolatile storage 550.

The recording unit 540 can record one or more of the digital program, the network data, the map file, the application and the link information to one identical apparatus (e.g. the nonvolatile storage 550) or to several different apparatuses (e.g. the PC 570).

For the possibility and necessity of downloading some content to the PC 570, please see the foregoing description.

A download control module (DCM, not shown) can be set in the apparatus 500 recording a digital program. The DCM receives link information (e.g. URL) from the acquiring unit 520, transmits the link information to the PC 570 via a home network (local network) or the Internet, and instructs the PC 570 to download network data from the Internet 560 on the basis of the link information. In such a case, the PC 570 needs to have been switched on and be operational. In the case of transmitting the link information to the PC 570 via the Internet, the IP address of the PC 570 needs to be pre- stored in the apparatus 500 recording a digital program. For the communication process between the apparatus 500 recording a digital program and the PC 570, various possible protocols may be employed.

A download execution module (DEM, not shown) can be set in the PC 570. The DEM receives the aforesaid link information and download instruction, sets up connection with the Internet 560, downloads network data corresponding to the link information from the relevant server, and stores the downloaded data to the local storage (e.g. hard disc). In the process of downloading, the DEM can create index information for the downloaded data and transmit the index information to a browsing module (BM, not shown).

The BM provides management function to the downloaded network data by generating the browsing interface to remind the user to play back or edit the downloaded content. The BM can also be installed in another apparatus, which has display function. For the purpose of convenience, the updated information can be synchronized with the PC 570.

The solution of implementing an instruction on the PC 570 to download the network data through hardware (e.g. DCM, DEM, BM) has been described above.

It is also possible to implement an instruction on the PC to download the network data through software. For instance, through running an MHP application, the link information can be sent to the PC 570 and the PC 570 is instructed to download the relevant network content. The MHP application can ask whether or not the user agrees this downloading or directly instruct the PC 570 to perform downloading.

Here, the MHP application can be obtained from the transmission stream, or reside in the apparatus 500 recording a digital program, or serve as a part of an MHP navigator. Such an MHP application can obtain directly the link information in the descriptor in a service information section (e.g. PMT, AIT) of the transmission stream or the link information in a link information file as transmitted with the transmission stream.

In order to prevent a third party from downloading content to the user's PC 570, several levels of authorization manners can be set. For instance, command authentication can be performed between the apparatus 500 recording a digital program and the PC 570. For another example, SSL can be used on the IP network. Also, cryptography can be used to ensure that the download request comes from an authorized apparatus. The DEM or the corresponding software in the PC 570 shall check the download request so as to prevent flooding the system with too many download requests.

When the PC 570 fails to set up connection with the Internet 560, the link information shall be buffered temporarily in the apparatus 500 recording a digital program or the PC 570. When the PC 570 can set up the connection, the PC 570 can perform downloading automatically.

In addition, multiple apparatuses 500 recording the digital program can be connected to the PC 570. In this case, the PC 570 shall have the server function so as to identify the different apparatuses 500 recording the digital program. A different apparatus 500 recording the digital program has a different download profile in the PC 570. For instance, some apparatuses 500 recording the digital program belongs to the couple, while some falls under their son. In this circumstance, it is necessary to classify the downloaded content and reflect the classification information in the download profile.

Fig. 6 is a schematic block diagram showing an apparatus of playing back a digital program according to an embodiment of the present invention. In general, the playing apparatus in the present embodiment comprises playback unit for playing back the recorded digital program, and network data acquiring unit for acquiring network data pre-stored in the local area when network data corresponding to the link information in the digital program needs to be played back. It is alternative that, the playback apparatus in the preset embodiment may further comprise unit for acquiring the relation between the network connection and the network data by polling a map file stored in the local area before reproducing the network data stored in the local area.

Specifically, numeral 610 denotes a playback apparatus; numeral 620 denotes a proxy unit; numeral 630 denotes a judgment unit; numeral 640 denotes an access unit; numeral 650 denotes a nonvolatile storage located in the local area; and numeral 660 denotes the Internet.

The playback unit 610 obtains the recorded digital program from the nonvolatile storage 650. The stored digital program includes audio/video streams and applications. Then, the playback unit 610 plays back the audio/video streams and runs the applications. When the application being run makes an Internet connection request, the Internet connection request is forwarded to the proxy unit 620.

The proxy unit 620 reads link information from the nonvolatile storage 650. The link information can be stored in a link information file (not shown) or in a map file.

Next, the judgment unit 630 judges whether the linked Internet content (hereinbefore referred to as "network data") has been recorded in the nonvolatile storage 650. If the linked Internet content has not been recorded in the nonvolatile storage 650, the access unit 640 directs the connection request to the corresponding server in the Internet 660 and obtains the linked content from the Internet 660.

If the linked Internet content has been recorded in the nonvolatile storage 650, the access unit reads the recorded network data out from the nonvolatile storage 650 via a file 10 and forwards the read network data to the playback unit 610.

The playback apparatus as shown in Fig. 6 can be a player, or a set top box with storage, or a recorded with the playing function. When the playback apparatus plays back the live program containing the Internet link, the proxy unit 620 is forbidden. When the playback apparatus plays back the program recorded in the nonvolatile storage 650, the proxy unit 620 is used so as to obtain network data. As described above, the network data comes from either the nonvolatile storage 650 or the Internet 660.

For instance, when the interactive application sends an Internet connection request, the proxy unit 620 checks URL. If the URL is listed in the recorded link information file or map file, then the proxy unit 620 will obtain the linked network data from the local nonvolatile storage 650; otherwise, the proxy unit 620 will obtain the linked network data from the Internet 660. It is alternative that the proxy unit 620 will try to obtain the linked network data from the Internet 660 first. When the linked network data cannot be obtained from the Internet, the proxy unit 620 will try to obtain the linked network data from the local nonvolatile storage 650.

Besides the interactive TV program, the digital program in the present invention can adopt other forms. The different forms of the digital program do not form limitations on the present inventions.

Although the preferred embodiments of the present invention have been described in detail, it is apparent that those of ordinary skill in the art can make various substitutions, alternations and changes. Therefore, such substitutions, alternations and changes shall be included in the present invention when they fall under the substance and scope of the appended claims.

Claims

CLAIMS:

1. A method of creating a link identifier in a digital program, including the steps of: confirming that the digital program is associated with link information; and integrating a corresponding link identifier into the digital program, wherein the link identifier indicates that the digital program is associated with link information.

2. The method of claim 1, wherein the confirming step includes: receiving an instruction that contains information related to the link identifier.

3. The method of claim 1, wherein the link identifier is a descriptor.

4. The method of claim 1, wherein the link identifier is a file.

5. The method of claim 1, wherein the link identifier contains the link information.

6. The method of claim 5, wherein the link identifier contains a redirect identifier for indicating that the link information is redirectable.

7. An apparatus of creating a link identifier in a digital program, comprising: confirming means for confirming that the digital program is associated with link information; and integrating means for integrating a corresponding link identifier into the digital program, wherein the link identifier indicates that the digital program is associated with link information.

8. The apparatus of claim 7, wherein the confirming means comprises receiving means for receiving an instruction, the instruction containing information related to the link identifier.

9. The apparatus of claim 7, wherein the link identifier is a descriptor.

10. The apparatus of claim 7, wherein the link identifier is a file.

11. The apparatus of claim 7, wherein the link identifier contains the link information.

12. The apparatus of claim 7, wherein the link identifier contains a redirect identifier for indicating that the link information is redirectable.

13. A method of recording a digital program, including the steps of:

(a) receiving a digital program which contains a link identifier for indicating that the digital program is associated with link information; (b) recording the digital program;

(c) acquiring corresponding link information in accordance with the link identifier; and

(d) recording network data corresponding to the link information.

14. The method of claim 13, wherein the link identifier contains the link information.

15. The method of claim 13, wherein the step (d) includes the steps of: downloading network data corresponding to the link information; and recording the network data.

16. The method of claim 13, wherein the link identifier contains a redirect identifier, and wherein the step (d) includes the steps of: transmitting the link information to an apparatus in accordance with the redirect identifier so that the apparatus can record network data corresponding to the link information.

17. The method of claim 13, further including the steps of: generating a map file indicating the relation between the network data and the link information; and recording the map file.

18. An apparatus of recording a digital program, comprising: receiving means for receiving a digital program which contains a link identifier for indicating that the digital program is associated with link information; acquiring means for acquiring corresponding link information in accordance with the link identifier; and recording means for recording network data corresponding to the link information and the digital program.

19. The apparatus of claim 18, further comprising downloading means for downloading the network data.

20. The apparatus of claim 18, wherein the link identifier contains a redirect identifier, the apparatus further comprising redirecting means for transmitting the link information to an apparatus in accordance with the redirect identifier so that the apparatus is able to record the network data.

21. The apparatus of claim 18, further comprising map file generating means for generating a map file which indicates the relation between the network data and the link information, the recording means being further used to record the map file.

22. A method of playing back a digital program, including the steps of: playing back a digital program that is associated with link information; and playing back network data pre- stored in a local area, when network data corresponding to the link information needs to be played back.

23. The method of claim 22, further including the step of: acquiring the network data on the basis of a map file and the link information.

24. An apparatus of playing back a digital program, comprising: playback means for playing back a digital program that is associated with link information; and network data acquiring means for acquiring network data pre- stored in a local area, when network data corresponding to the link information needs to be played back.