KR101262342B1 - Internet Protocol Television Broadcasting System And Receiver And Data Transmission System And Method For Internet Protocol Television System - Google Patents

Abstract

The present invention provides a two-way data service through each channel when watching a plurality of channels on the IPTV (Internet Protocol Television).

The present invention selectively connects one or more multicasting channels and transmits video / audio signals and independent data information including interlocking data information.

In addition, there is no direct connection with the video / audio signal, but supplementary metadata information such as news, weather, traffic, securities, messenger, short messages, etc., which require information at any time by the user's request, is transmitted through one fixed channel. Allow the device to receive at all times.

In addition, IP network, which is a broadband communication network infrastructure, is used, and detailed information on auxiliary metadata is provided in a unicasting form through a return pass by utilizing a feature that makes it easy to secure a return pass bandwidth. Auxiliary metadata information and detailed information thereof are displayed on the screen on which the video / audio signal is displayed by the screen overlapping technique.

IPTV broadcasting system, IP receiver, two-way data transmission, auxiliary metadata

Description

Bi-directional data transmission apparatus and method of IPTV broadcasting system and receiver and IPTV system {Internet Protocol Television Broadcasting System And Receiver And Data Transmission System And Method For Internet Protocol Television System}

1 is a diagram illustrating a conventional IPTV broadcast data transmission system.

2 is a diagram illustrating a multi-access configuration for bidirectional data transmission of an IPTV system according to an embodiment of the present invention.

3 is a block diagram showing a detailed configuration of the receiving device of FIG. 2 according to an embodiment of the present invention.

4 is a flowchart illustrating a process of a bidirectional data transmission service through multi-access according to an embodiment of the present invention.

5 is a diagram illustrating an example of a user screen on which auxiliary data broadcasting is implemented through multi-access according to an embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

100: IPTV broadcasting system 200: communication network

300: IP receiver

The present invention relates to an IPTV system and a receiver for providing a bidirectional data service through each channel when watching a plurality of channels using an Internet Protocol Television (IPTV), and a bidirectional data transmission apparatus and method of an IPTV system.

Data broadcasting, which started with subtitle broadcasting, text broadcasting, program guide, etc. in analog broadcasting environment, is combined with the development of digital technology today and delivers various additional data linked with video screen or independently.

In particular, recently, data broadcasting has been emphasized as an interactive service that enables users to directly and indirectly participate as an interactive infrastructure is established through a return path.

Such data broadcasting is typical of satellite broadcasting using satellite, cable broadcasting using cable network, and IPTV service using IP (Internet Protocol) network.

However, satellite broadcasting using satellites and cable broadcasting using cable networks have a limited infrastructure bandwidth in providing data broadcasting services.

Therefore, in the process of producing data broadcasting, only one or two pieces of data information in a multicasting transmission bandwidth are loaded together in a video / audio channel and transmitted in one MPEG2 TS (Moving Picture Experts Group-2 Transport Stream) format. do.

1 is a diagram illustrating a conventional IPTV broadcast data transmission system.

As shown, a satellite network connecting the data broadcasting system 10 including the transmission server 12 and the reception device 30 integrally formed with the set-top box or the receiver and the transmission server 12 and the reception device 30. Or a communication network 20 composed of a cable network.

In the data broadcasting system 10, the transmission server 12 uses a communication network 20 composed of a satellite network or a cable network to interwork with video / audio broadcasting on each of the multicasting channels 22 and 24. The data information is bundled into one and transmitted in the form of MPEG2 TS. In addition, the independent data information without the general broadcast program is transmitted through the multicasting channel 26 in the form of MPEG2 TS.

Receiving device 30, which is integrally formed in the set-top box or the receiver, tunes the channel selected by the user through the internal tuner 32 to receive only the signal loaded on the corresponding channel and the video from the signal received through the demux 34. Classify information, audio information, and data information.

Thereafter, the signals of the classified video information, audio information, and data information are decompressed through the decoder 36, and then restored to the original signal and displayed on the screen.

As described above, the transmission method using the communication network 20 composed of a satellite network or a cable network transmits auxiliary data to a video / audio broadcast containing interlocking information in consideration of limited band bandwidth. You can only provide services.

Therefore, in the data broadcasting standard, data is transmitted between a transmitting server and a receiving device to transmit predetermined data in both directions in order to overcome insufficient bandwidth.

However, although there are provisions for media such as telephone lines and cables for communication media for two-way communication, there is no regulation on the classification of information data according to the type of data broadcasting service provided. There is also no provision on how to connect.

In this situation, the conventional data broadcasting transmission method has a burden of adjusting the bandwidth of video / audio information among the total transmission bandwidth and the number of data broadcasting services that can be simultaneously transmitted is limited. It is inconvenient to change the channel to another specific channel defined to be able to receive data information from the channel currently being viewed.

In addition, if the same service is to be received in several channels, the sending server must transmit the same data information to each channel, which is very inefficient in bandwidth usage.

As described above, in order to receive a desired data service, the existing interactive data broadcasting service is inconvenient to change a channel from a channel currently being viewed to a specific channel capable of data service, and provides simultaneous service in multiple channels. In this case, there is a problem in that the efficiency of the bandwidth is reduced.

The technical problem of the present invention for solving the above problems is to selectively connect the video / audio channel and the independent data broadcasting channel including the interlocking data information in the interactive data broadcasting service of the IPTV receiver using the IP network, The meta data information channel provides a bidirectional data broadcasting service in all channels by using a multi-access method that is fixedly connected, thereby providing various auxiliary metadata information without changing a channel to another specific channel while the user watches the current channel. The purpose is to make it available.

That is, the present invention enables the supplementary metadata information provided by one or two limited channels in the existing limited channel in the bidirectional data broadcasting service of the IPTV receiver using the IP network to be provided in all channels. Its purpose is to enable data services.

In addition, the present invention is an auxiliary metadata from a multicasting channel that is constantly connected when the auxiliary metadata information of the user is requested in the state of outputting a video signal for any channel that the user watches through the screen of the receiving device The purpose is to extract the information and display it on the screen of the channel being viewed using a translucent screen overlapping technique (alpha blending).

In accordance with the present invention, an IPTV broadcasting system allocates one or more multicasting channels to a muxed video / audio signal, linked data, independent data, and auxiliary metadata information according to a program scheduling schedule. A transmission server for transmitting by; DB server for retrieving the detailed information of the auxiliary metadata information requested by both services in the IP receiving device from the DB to provide to the return server; And a return server that detects the detailed information request of the auxiliary metadata information of the IP receiver and provides the DB server, and provides the detailed information retrieved and provided from the DB server to the IP receiver in unicasting form. It is done.

In addition, the IPTV broadcast receiving apparatus according to the present invention comprises a LAN card for maintaining transmission and reception of video / audio signals and data information by connecting an IP network to a physical interface of the IP receiving apparatus; By analyzing the multicasting IP address of the channel, the channel including the video / audio signal and the linked data information or the channel containing the independent data information is selectively connected, and the channel containing the supplementary metadata information. An IP tuner which receives a signal transmitted through a corresponding channel through a fixed connection at all times; A demux for separating the integrated video / audio signal and data information of MPEG2 TS type received from the IP tuner, respectively; A decoder which decompresses the signal separated by the demux and restores the original signal; A return path client module connected to the IP tuner and requesting a request signal for detailed information to the IPTV broadcasting system as a bidirectional service when detailed information is requested for auxiliary metadata information received through a fixed channel; And a frame buffer which sequentially processes the signal recovered by the decoder in units of frames and sequentially transmits the signal to the display means.

In addition, the bidirectional data transmission apparatus of the IPTV system according to the present invention selectively connects the video / audio multicasting channel including the basic interlocking data information and the multicasting channel transmitting the independent data information, and the auxiliary metadata information is loaded. A data broadcasting system including a transmission server to which the multicasting channel is fixedly connected; By analyzing the multicasting IP address of the channel, the channel including the video / audio signal and the linked data information or the channel containing the independent data information is selectively connected, and the channel containing the supplementary metadata information. And a demux for separating the integrated video / audio signal, interlocked and supplementary metadata information received from the IP tuner, and receiving the signal transmitted through the corresponding channel through the fixed connection. A decoder which decompresses each signal separated from and decompresses the original signal, and processes the video / audio signal, interlocked and auxiliary metadata information restored by the decoder in units of frames, and sequentially transmits them to the display means. For auxiliary metadata information received over buffers and optionally fixed channels. IPTV receiving device for the request signal of the three information to the data broadcasting system comprises a return path request to the client module for two-way service, and; The data broadcast system and the IP receiving device is connected, characterized in that composed of an IP network that accommodates a wide bandwidth.

In addition, in the IPTV system according to the present invention, the bidirectional data transmission method includes (a) an IPTV broadcasting system selectively connecting one or more multicasting channels to provide video / audio signals and independent data information including basic interlocking data information. Transmitting and supplementing meta data information by always fixedly accessing another multicasting channel; (b) the IPTV receiving apparatus recovers and displays a video / audio signal including basic linked data information transmitted through any one channel selected through analysis of an IP address; (c) determining whether a broadcast request for auxiliary metadata information is detected while displaying the video / audio broadcast including the basic linked data information; (d) extracting auxiliary metadata information from a channel which is always fixedly connected when a broadcast request for auxiliary metadata information is detected; (e) decoding the extracted auxiliary metadata information and displaying the same by using a screen overlapping technique; (f) determining whether a request for detailed information on the displayed supplementary metadata information is detected; (g) requesting detailed information on specific supplementary metadata information from the IPTV broadcasting system when a request for detailed information of supplementary metadata information is detected; (h) retrieving detailed information on specific auxiliary metadata information from a DB according to a request of the IPTV receiver and providing the IPTV receiver in a unicasting format; (i) displaying detailed information provided by the IPTV broadcasting system by using a screen overlapping technique in connection with the data broadcasting being used.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like parts throughout the specification.

In addition, when a part is said to "include" a certain component, it means that it can further include other components, except to exclude other components unless otherwise stated.

In addition, the term module described herein refers to a unit for processing a specific function or operation, which may be implemented in hardware or software, or a combination of hardware and software.

Now, an IPTV broadcasting system, a receiving apparatus, and a bidirectional data transmission method and system thereof according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

2 is a diagram illustrating a multi-access configuration for bidirectional data transmission of an IPTV system according to an embodiment of the present invention.

As shown, the present invention is installed on the IPTV broadcasting system 100 including the transmission server 102, the DB server 104, and the return server 106 and the user end, and an IP receiving apparatus which is integrated in a set-top box or a receiver. 300 and an IP network 200 connecting the data broadcasting system 100 and the IP receiving apparatus 300.

The IPTV broadcasting system 100 includes a transmission server 102, a DB server 104, and a return server 106. The transmission server 102 is muxed according to a predetermined program scheduling schedule. The audio signal and the linked data information are loaded on the multicasting channel (Ch # 1,202) in the form of MPEG2 TS and transmitted to the IP network 200.

Similarly, video / audio signals and linked data information of other broadcast programs are loaded on another multicasting channel (Ch # 2,204) in the form of MPEG2 TS and transmitted to the IP network 200.

In addition, the transmission server 102 transmits supplementary metadata information such as news, weather, traffic, stock information, messenger, short message, etc. in order to provide ancillary data broadcasting service in all channels (Ch # 4,208). The fixed connection is maintained at all times for the multicasting channel Ch # 4,208, which is loaded on and transmitted to the secondary meta data information.

In addition, the transmission server 102 transmits the independent data information, which does not include the video / audio signal, to any one of the multicasting channels (Ch # 3,206) to the IP network 200 as necessary.

The DB server 104 retrieves the detailed information of the auxiliary metadata information requested by the IP receiving apparatus 300 from the DB (not shown) and provides it to the return server 106.

The return server 106 provides the DB server 104 with the detailed information request of the auxiliary metadata information of the IP receiving apparatus 300, and the detailed information retrieved and provided by the DB server 104 in the form of unicasting. IP network 200 is sent.

Unlike the existing satellite and cable networks, the IP network 200 accommodates a wide bandwidth as a broadband communication network infrastructure, and receives the video / audio signal and various data information transmitted from the IPTV broadcasting system 100. And maintains both services between the IPTV broadcasting system 100 and the IP receiving apparatus 300 through a return pass.

In addition, as shown in FIG. 3, the IP receiving apparatus 300 includes a LAN card 301, an IP tuner 302, a demux 304, a decoder 306, a return path client module 308, and a frame buffer. 310, a user service input module 312, a service selection controller 314, a media controller 316, and an application controller 318.

The LAN card 301 is connected to the IP network 200 as a physical interface of the IP receiving apparatus 300, and various video / audio signals and data information transmitted from the IPTV broadcasting system 100 through the IP network 200. And transmits the data request signal of the IP receiving apparatus 300 to the IP network 200 to be transmitted to the IPTV broadcasting system 100.

The IP tuner 302 multicasts one channel of each channel according to a user's request, one of the program channels 202 and 204 including the video / audio signal and the linked data information, or the channel 206 carrying the independent data information. Selectively connect through the IP address.

In addition, the IP tuner 302 is fixedly connected to the IP address of the multicasting channel (Ch # 4,208) carrying auxiliary metadata information such as news, weather, traffic, securities and messengers, and short messages. Access metadata information.

Accordingly, the IP tuner 302 of the IP receiving apparatus 300 may always receive auxiliary metadata information while selectively connecting the general video / audio channel.

That is, the IP tuner 302 accesses a corresponding channel suitable for the user's selection among a plurality of video / audio broadcasting channels by analyzing an IP address, and always accesses an auxiliary metadata information channel so that a request for an auxiliary metadata service from a user can be made. If detected, information is provided by screen overlapping technique (alpha blending).

The demux 304 separates the integrated video / audio and data signals in the form of MPEG2 TS received through the IP tuner 302 into a video signal, an audio signal and a data signal, respectively.

The decoder 306 decompresses the video signal, the audio signal, and the data signal separated by the demux 304, restores the original signal, and transmits the decompressed video signal to the display means.

The return path client module 308 requests the return server 106 provided in the IPTV broadcasting system 100 in the form of unicasting according to a user command when additional detailed information other than the basic information of the supplementary metadata information is required, Receive the corresponding information.

The frame buffer 310 processes the video signal, the audio signal, and the interlocking data information reconstructed by the decoder 306 in units of frames so as to be sequentially transmitted to the display means for display.

The frame buffer 310 controls the transmission, waiting, and flow of data frames to provide a seamless service of a screen under the control of the media controller 316.

The user service input module 312 receives the user's channel selection and service selection and provides the result to the service selection controller 314.

The service selection controller 314 determines and controls reception of general video / audio signals and linked data information or reception of supplementary metadata information according to a user's selection.

The media controller 316 controls multimedia such as video, image, text, etc. necessary according to the type of application, and thus controls the decoder 306 and the frame buffer 310 accordingly.

The application controller 318, in conjunction with the control of the service selection controller 314, stores the video / audio program and the auxiliary metadata information such as news, weather, traffic, and fortune-telling according to the type and time of the service requested by the user. Overlapping the application on the screen or when the service request is changed, it terminates the previously running application and controls to display the selected new application.

Accordingly, the IP receiving apparatus 300 selects one of a general video / audio program or a standalone data broadcasting channel selected by a user and provides a service such as news, weather, fortune telling, traffic, securities, messenger, short message, etc. When auxiliary data information is required, corresponding data is always obtained from the multicasting channels Ch # 4,208 carrying auxiliary meta data information being connected and processed by the display means by the screen overlapping technique (alpha blending).

In addition, when more detailed information and connection are requested for the displayed auxiliary metadata information, the return path client module 308 in the IP receiving apparatus 300 is provided in the IPTV broadcasting system 100 through the unicasting channel 210. The return server 106 is connected to request the corresponding data.

Accordingly, the return server 106 provided in the IPTV broadcasting system 100 provides the DB server 104 with a request for detailed information requested from the IP receiving apparatus 300, and thus the DB server 104 is shown. Search for the corresponding information from the DB that is not provided to the IP receiving apparatus 300 in the form of unicasting through the return server 106.

4 is a flowchart illustrating a process of a bidirectional data transmission service through multi-access according to an embodiment of the present invention.

Supplementary metadata specific to the user service input module 312 in a state in which a user selects and watches one channel among general video / audio channels including the linked data information using the IP receiver 300 (S401). It is determined whether a signal for requesting a broadcast is detected (S402).

If the user's selection for requesting a specific supplementary metadata broadcast is detected in S402, the service selection controller 413 provides the information about the IP tuner 302, the demux 304, and the application controller 318.

Accordingly, the IP tuner 302 is always connected and extracts the selected auxiliary metadata from the multicasting channels Ch # 4,208 which transmit auxiliary metadata information such as news, weather, traffic, securities, messengers, and short messages. S403).

Thereafter, the video / audio and interlocking data information and the auxiliary metadata information received through the channel selected by the user are separated into the video signal, the audio signal and the data signal through the demux 304, and then through the decoder 306. Compression is decompressed and restored to the original signal.

Thereafter, the restored video / audio signal and data information are applied to the frame buffer 310 under the control of the media controller 316, and the transmission and waiting and the flow of the restored data frame are controlled and transmitted to the display means. Displayed in (Alpha Blending).

In order to display the auxiliary metadata information by the screen overlapping technique, the coordinate value of the output screen frame image is calculated based on the size of the output screen set by the user, the amount of the data providing contents, and the items.

Then, the restricted area is read from the stored image of the source frame to generate an image, and then displayed on the screen being viewed by the screen overlapping technique.

In the process of providing the IP bidirectional data broadcasting service requested by the user as described above, it is determined whether another request for auxiliary metadata information is detected by the user service input module 312 (S406).

When the request for the other auxiliary metadata information is detected in S406, the service selection controller 314 transmits the requested service command to execute the aforementioned step S403 (S412).

However, if a request for other auxiliary metadata information is not detected in S406, it is determined whether a request for more detailed information is detected for the selected auxiliary metadata information (S407).

If the request for detailed information is not detected in S407, an IP bidirectional data broadcasting service is provided to continuously maintain the current state.

However, when a request for detailed information is detected, the return path client module 308 connects the return server 106 in the IPTV broadcasting system 100 through the unicasting channel and then requests detailed information about the auxiliary metadata broadcasting ( S408).

Accordingly, the return server 106 transmits a request for detailed information about specific supplementary metadata to the DB server 104, whereby the DB server 104 retrieves the corresponding detailed information from a DB (not shown) and returns the server. To 106.

The return server 106 transmits the detailed information provided from the DB server 104 to the IP receiving apparatus 300 through the unicasting channel (S409).

Therefore, the detailed information received through the unicasting channel is processed through the demux 304, the decoder 306, and the frame buffer 310 to display the screen overlapping technique (alpha blending) on the screen in association with the data broadcasting currently provided. Provides information to (S410).

As described above, the user can use the detailed information of the selected IP bidirectional data broadcast, and as this process is selectively repeated, the user can quickly and conveniently use various IP bidirectional data broadcast services without switching channels in the current channel he is viewing. It may be (S411).

5 is a diagram illustrating an example of a user screen on which auxiliary data broadcasting is implemented through multi-access according to an embodiment of the present invention.

As shown, the screen 500 is a messenger driven as a form of auxiliary interactive data broadcasting on the channel.

Reference numerals 502 and 506 denote semi-transparent screen overlapping images shown through the alpha blending effect.

In addition, reference numerals 504 and 508 indicate the appearance of an auxiliary interactive data broadcasting service such as weather, cooking.

The embodiments of the present invention described above are not only implemented by the apparatus and method but may be implemented through a program for realizing the function corresponding to the configuration of the embodiment of the present invention or a recording medium on which the program is recorded, The embodiments can be easily implemented by those skilled in the art from the description of the embodiments described above.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, It belongs to the scope of right.

According to the above-described configuration, it is possible to conveniently and quickly provide a plurality of various interactive data services to a user using IPTV without switching the screen of a channel currently being viewed for accessing a specific interactive data service.

In addition, the efficient multicasting channel distribution minimizes the bandwidth limit required for bidirectional data service and always fixedly connects to the IP receiving device, thereby providing a quick service by shortening the waiting time due to service switching.

In addition, by providing a data service menu configuration and a screen on the IPTV with a video / audio screen using a multi-overlapping technique (alpha blending), the broadcasting program can be conveniently used while watching the broadcast program together.

In addition, it is possible to provide a personalized EPG service in the future by extending the bidirectional data transmission method according to the present invention, and through the registration of the preferred service for the region of interest bidirectional data service, personalized information service that meets individual tastes. There is an effect that can be provided.

Claims (14)

Video / audio broadcast signals and linked data muxed according to a program scheduling schedule, wherein the linked data is additional data linked to the video broadcast signal, and stand-alone data, where stand-alone data is data not related to the video broadcast signal. Outgoing to allocate and transmit one multicasting channel for each of the supplementary meta data including the information which is not linked with the video broadcast signal and news, weather, traffic, stock information, messenger, and short message information which are frequently requested by the user. server; DB server for retrieving the detailed information of the auxiliary metadata requested by both services in the IP receiving device from the DB to provide to the return server; An IPTV broadcasting system including a return server that detects a request for detailed information of auxiliary metadata of the IP receiver and provides it to the DB server, and provides the detailed information retrieved and provided from the DB server to the IP receiver in unicasting form. . The method of claim 1, And the transmission server selectively connects a multicasting channel carrying video / audio broadcasting signals, interlocking data information, and independent data information, and always permanently connects a multicasting channel carrying auxiliary metadata information. delete A LAN card for accessing an IP network through a physical interface of the IP receiver and maintaining transmission and reception of video / audio broadcast signals and data information; Analyzing a multicasting IP address of a channel, the video / audio broadcast signal and interlocked data, wherein the interlocked data is additional data linked to the video broadcast signal, or standalone data, where standalone data is the video. Data not related to the broadcast signal, which is not linked with the video broadcast signal-selectively access any one of the channels on which the news, weather, traffic, stock information, messenger, short messages requested by the user from time to time An IP tuner configured to receive a signal transmitted through a corresponding channel by constantly accessing a channel carrying auxiliary metadata including information; A demux for separating the integrated video / audio broadcast signal and the data signal of MPEG2 TS type received from the IP tuner; A decoder which decompresses and decompresses each signal separated from the demux; A return path client module connected to the IP tuner and requesting a request signal of the detailed information to the IPTV broadcasting system as a bidirectional service when detailed information is requested for auxiliary metadata information received through a fixed channel; And a frame buffer which sequentially processes the video signal, the audio signal, and the linked data information restored by the decoder in units of frames, and sequentially transmits them to the display means. 5. The method of claim 4, A user service input module configured to receive a channel selection and a service selection of a user and output a result thereof; A service selection controller controlling the IP tuner and the demux by determining reception of a general video / audio broadcast signal and linked data information or reception of supplementary metadata information according to a signal applied from the user service input module; A media controller that manages multimedia of a moving picture, an image, and a text according to an application type, and controls the decoder and the frame buffer accordingly; And an application controller for controlling an application of ancillary metadata information superimposed on a screen in response to the control of the service selection controller and being superimposed on a screen, and controlling an application selected when a service request is changed. IP receiver. The method of claim 5, The frame buffer is an IP receiving apparatus that controls the transmission, waiting, and flow of data frames under the control of the media controller. The method of claim 5, The auxiliary metadata information requested by the user is displayed by a screen overlapping technique. IPTV broadcasting system, IP receiver and IP network, The IP receiving apparatus analyzes a multicasting IP address of a channel to determine a channel or independent data including a video / audio broadcast signal and linked data, wherein the linked data is additional data linked to the video broadcast signal. Stand-alone data is data not related to the video broadcast signal, and selectively connects any one channel among channels in which the video broadcast signal is not linked with the video broadcast signal, and news, weather, traffic, and stock information requested from time to time by the user. And an IP tuner configured to receive a signal transmitted through a corresponding channel by constantly accessing a channel carrying auxiliary metadata information including messenger and short message information; A demux for separating the integrated video / audio broadcast signal, the interlocking and supplementary metadata information received from the IP tuner, respectively; A decoder which decompresses each signal separated from the demux and restores the original signal; A frame buffer for sequentially processing the video / audio broadcast signal, the interlocking and auxiliary metadata information restored by the decoder in units of frames, and sequentially transmitting the same to the display means; Optionally, a return path client module for requesting the IPTV broadcasting system as a bidirectional service request signal for detailed information on the supplementary metadata information received through a fixed channel. 9. The method of claim 8, The IPTV broadcasting system includes a transmitting server, and the transmitting server selectively connects a channel carrying video / audio broadcasting signals, interlocking data information, and independent data information, and always fixes a channel carrying auxiliary metadata information. Bi-directional data transmission device of IPTV system to access. 9. The method of claim 8, The IPTV broadcasting system includes a DB server that retrieves detailed information of auxiliary metadata requested by the IP receiving apparatus from a DB and provides it to a return server; And a return server for providing a detailed information request of the IP receiving apparatus to the DB server and providing the detailed information provided from the DB server to the IP receiving apparatus in a unicasting form. 9. The method of claim 8, The IP receiving apparatus includes a user service input module for receiving a channel selection and a service selection of a user and outputting a result thereof; A service selection controller controlling the IP tuner and the demux by determining reception of a general video / audio broadcast signal and linked data information or reception of supplementary metadata information according to a signal applied from the user service input module; A media controller that manages multimedia of a moving picture, an image, and a text according to an application type, and controls the decoder and the frame buffer accordingly; In response to the control of the service selection controller, an application of meta data information supplementary to the video / audio program currently being broadcast is displayed on the screen, and when the service request is changed, the IPTV system further includes an application controller for controlling another application. Bidirectional data transmission device. (a) The IPTV broadcasting system selectively connects one or more multicasting channels to interlock data with the video / audio broadcast signal, wherein the interlocked data is additional data linked to the video broadcast signal, and standalone data. Independent data is not related to the video broadcast signal, and is not linked to the video broadcast signal, and news, weather, traffic, and stock information, which is frequently requested by the user, is always fixedly connected to another multicasting channel. Transmitting the supplementary metadata information including the messenger and the short message information; (b) the IP receiving apparatus recovering the linked data and the video / audio broadcasting signal transmitted through any one channel selected through analysis of the IP address and displaying the same on the screen; (c) determining whether a request for auxiliary metadata information is detected while displaying the linked data and the video / audio broadcast signal; (d) extracting auxiliary metadata information from a channel which is always fixedly connected when a broadcast request for auxiliary metadata information is detected; (e) decoding the extracted auxiliary metadata information and displaying the same by using a screen overlapping technique; (f) determining whether a request for detailed information on the displayed supplementary metadata information is detected; (g) requesting detailed information on specific supplementary metadata information from the IPTV broadcasting system when a request for detailed information of supplementary metadata information is detected; (h) retrieving detailed information on specific auxiliary metadata information from a DB according to a request of the IP receiving apparatus and providing the detailed information to the IP receiving apparatus in a unicasting format; (i) displaying the detailed information provided by the IPTV broadcasting system in a screen overlapping manner in association with the data broadcasting being used. The method of claim 12, In step (e), when the auxiliary metadata information is detected in the state of displaying the supplementary metadata information on the screen of the video broadcast, if the request for the other auxiliary metadata information is detected, the newly selected corresponding auxiliary metadata information is extracted from the constantly connected channel. Next Bidirectional data transmission method of IPTV system to replace existing data service screen and display as new screen. The method of claim 12, In the step (d), the auxiliary metadata information extracted from the channel that is always fixedly connected is calculated based on the size of the output screen, the amount of data providing content, and the items of the output screen frame image. A bidirectional data transmission method of an IPTV system that generates an image by reading a restricted area from an image of a source frame and displays the image on a screen that is viewed by a screen overlapping technique.

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