KR100914132B1 - System and method for reducing channel zapping time in internet protocol telelvision - Google Patents

Abstract

A device and a method for shortening a channel zapping time in an IPTV system are provided to directly change a channel without reading and processing data necessary for channel change in a receiving device during channel zapping, thereby shortening a channel zapping time. A decoder(320) converts data outputted from a demultiplexer into broadcasting data. When a preset event is generated before a user requests to change a channel, a version check and control unit(340) receives a broadcasting stream provided from a transmitting side. The version check and control unit extracts PID(Program IDentifier) information from the broadcasting data converted through the decoder. The version check and control unit checks and processes a version of the PID information. When a user requests a channel change, the version check and control unit changes a channel by pre-stored PID information.

Description

Device and method for shortening channel zapping time in the IP system {SYSTEM AND METHOD FOR REDUCING CHANNEL ZAPPING TIME IN INTERNET PROTOCOL TELELVISION}

The present invention relates to an IPTV system, and more particularly, to reduce channel zapping time in an IPTV system that can reduce the user's boredom during channel zapping time by reducing the time required for channel switching (zapping) in the IPTV system. An apparatus and method for shortening.

In general, IPTV is a service that provides various multimedia contents (video, audio, document, graphics, etc.) through an IP (Internet Protocol) network that is guaranteed quality, security, and reliability, and includes both a real-time broadcasting service and a VOD service. can do.

The IPTV system is composed of a content providing server for transmitting content (program) to the IP network, and a set-top box for receiving and playing the content from the IP network. The content transmitted through the IP network is compressed such as MPEG. It is delivered in the form of a coded bit stream. Accordingly, the set-top box decodes it and displays it on the display screen.

However, in this IPTV system, when channel switching (zapping), channel zapping is performed by receiving broadcast program information and PSI / SI information from a transmitting side, which is a content providing server, and parsing data entering a buffer with reference thereto. Will try.

At this time, the channel zapping starts due to the effects of digital broadcast signal processing, command processing, network delay, STB layer delay of the set-top box, MPEG decoder time, and the like. The time required for complete zapping to be performed (hereinafter, channel zapping time) is delayed from 4 seconds to 8 seconds. Viewers feel bored during this delay, which causes a lot of inconvenience to viewers.

The present invention has been made to solve the above problems, and provides an apparatus and method for shortening the channel zapping time by implementing a channel switching immediately without the process of reading and processing data required for channel switching in a receiving device when channel zapping. For the purpose.

The apparatus for shortening the channel zapping time in the IPTV system according to the present invention for achieving the above technical problem, demultiplexing the broadcast stream (encoded) provided by the transmitting side to be separated into the compressed broadcast data Demux; A decoder which decodes the data output from the demux and converts the data into broadcast data; A graphics module for converting the broadcast signal converted by the decoder into a graphic signal and outputting the converted graphic signal; And requesting to receive a broadcast stream provided from the transmitter when an event designated in the system is generated, and after receiving the broadcast stream, extract PID (Program IDentifier) information from the broadcast data converted through the decoder to generate the PID information. It includes a version check and control unit to check the version of and process it.

According to an example of the present invention, the apparatus may further include storage for storing the PID information processed by the version check and the controller.

According to an example of the present invention, the version check and control unit stores and updates the PID information if the version of the PID information is a higher version, and discards if the version of the PID information is not higher than the previously stored previous PID information. It is characterized by.

According to an example of the present invention, the broadcast stream includes an audio stream and a video stream of the corresponding content, and a program specific information (PSI) section having PID information of the audio stream and the video stream.

According to an example of the present invention, the event, at the time of booting the device for receiving the broadcast stream, during a predetermined period of time, the idle time in which the operation of the device is not performed, real time cases It may include.

According to an aspect of the present invention, there is provided a method for shortening a channel zapping time in an IPTV system, the method comprising: receiving a broadcast stream encoded and provided at a transmitting side when an event occurs; Demultiplexing and decoding the received broadcast stream; Extracting PID (Program IDentifier) information from the decoded and output data and checking a version of the PID information; If the version of the PID information is a higher version, storing in the storage and automatically updating; And discarding the received PID information if the version of the PID information is not a higher version than previously stored previous PID information.

According to an example of the present invention, the event, at the time of booting the device for receiving the broadcast stream, during a predetermined period of time, the idle time in which the operation of the device is not performed, real time cases It may include.

In addition, the broadcast stream is composed of an audio stream and a video stream of the corresponding content, and a program specific information (PSI) section having PID information of the audio stream and the video stream, and may be separated into each through demultiplexing.

The channel switching method in the IPTV system according to the present invention for achieving the technical problem, the step of inputting a channel switching request by the user; Retrieving the input channel switch signal from previously stored program specification information (PSI) and extracting PID information corresponding to the channel switch signal; And performing channel switching with reference to the extracted PID information.

At this time, the PID information is automatically updated to a higher version.

According to the present invention described above, the set-top box downloads the PID information that influences channel zapping in advance and attempts channel zapping with reference thereto, thereby rapidly reducing the time required for channel zapping to within 2 seconds from 4 seconds to 10 seconds. I was. As a result, the user's convenience is improved by eliminating the boredom that the viewer feels during the channel switching time.

Hereinafter, an apparatus and method for shortening channel zapping time in an IPTV system according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

The broadcast data referred to in this embodiment is data including a plurality of contents (programs) transmitted through one logical channel.

In addition, the broadcast stream referred to in this embodiment refers to a continuous collection of actual data for transmitting digital broadcast, and is data including a video stream and an audio stream of the corresponding broadcast content and program information related thereto.

1 to 3 will be described with reference to this.

1 is a diagram illustrating an apparatus for shortening a channel zapping time in an IPTV system according to an embodiment of the present invention, and FIG. 2 is a diagram illustrating a configuration of a digital broadcast receiving apparatus according to an embodiment of the present invention.

For reference, FIGS. 1 and 2 schematically illustrate only components that play a major role in implementing the present invention, and various functional blocks may be added in addition to those shown.

First, referring to FIG. 1, an IPTV system according to an exemplary embodiment of the present invention is connected to a broadcast transmission system 100 that provides a television broadcast service through the Internet 200, and is connected to the Internet 200. And a digital broadcast receiving device 300 for receiving broadcast data provided by the PDP and displaying the broadcast data on the display device 400.

The display device 400 may include a CRT, an LCD, a PDP or an OLED television or a monitor.

The broadcast transmission system 100 includes a base band 110 and an encoder 120, an IP MUX 130, a reception restriction server (CAS / DRM server 140), a data broadcast system (DBS 150), and the like. It includes.

Here, the base band 110 refers to a source signal region of audio data and video data containing actual data. In general, since it is difficult to transmit the baseband signal as it is, a carrier is loaded on a carrier.

The encoder 120 performs an encoding function of encrypting audio data and video data transmitted together with a carrier wave in a data format suitable for digital broadcasting.

In this case, the encoder 120 may use the MPEG standard as the encryption method of the audio data and the video data. However, other encryption schemes are applicable if possible.

The IP MUX 130 muxes the data input from the reception restriction server 140 and the data broadcasting system 150 as well as the data encoded by the encoder 120 and outputs the data in the form of a bit stream (hereinafter, referred to as a broadcast stream). Called).

In the present embodiment, the reception restriction server 140 is responsible for restricting user access through device authentication using the DRM solution. Here, the displayed CAS is an abbreviation of Conditional Access System and is a technology for providing a paid viewing service for each viewer. For example, in pay-per-view services of IPTV, viewer ratings are determined according to the price charged by the viewer, so that viewers have the right to watch a channel corresponding to their rating. If selected, the corresponding viewer checks whether the viewer has the right to view the selected program channel so that the encoded broadcast data is descrambled if there is the right to view.

DRM stands for Digital Right Management, and is a content copyright protection technology for preventing illegal copying of content on the Internet.

The data broadcasting system 150 generates PSI (Progarm Specific Information) having EPG information related to program programming and program specification information, that is, information on which program to select and decode from a plurality of programs, respectively, to generate an IP MUX 130. To pass).

In general, the PSI is composed of four tables. In this embodiment, the APID in which the identifier (PID) of each program among the four tables of the PSI and individual bit strings such as video, audio, and general data constituting each program are transmitted is transmitted. PMT (Program Map Table) that records a list of (Audio Program ID), VPID (Video PID), DPID (Data PID) (hereinafter collectively called PID), and PAT (Program Association Table) containing PID information of PMT. Refer to the channel zapping.

According to this configuration, when the broadcast transmission system 100 encrypts and transmits broadcast data including a plurality of programs, the data generated by the reception restriction server 140 and the data broadcast system 150 (for example, the viewer). Authorization information, PSI information) is muxed and modulated, and then transmitted to the receiving end via the Internet 200. The data transmitted to the receiver is transmitted in the form of a broadcast stream.

Then, the digital broadcast receiving apparatus 300, which is a receiving end, receives the muxed broadcast stream through the broadcast transmission system 100, reversely demuxes and decodes the signal, and outputs the decoded to the display apparatus 400.

The digital broadcast reception device 300 according to the present embodiment may be an IPTV set top box (STB).

As shown in FIG. 2, the digital broadcast receiving apparatus 300 includes a demux 310, a decoder 320, a graphics module 330, a version check and control unit 340, and a storage 350. It can be configured.

The demux 310 demultiplexes the muxed broadcast stream through the broadcast transmission system 100 and separates it into compressed broadcast data. Through this, the broadcast stream may be divided into an encrypted video stream, an audio stream, a general data stream, and a PSI section having identifier (PID) information of these streams.

The decoder 320 decompresses and decrypts the encrypted data according to a compression method and converts the encrypted data into broadcast data.

The graphic module 330 converts the broadcast data converted through the decoder 320 into a graphic signal (AV signal) and outputs the converted graphic signal to the display apparatus 400.

The version check and control unit 340 requests to receive the broadcast stream provided from the broadcast transmission system 100 when an event designated in the system occurs, and after receiving the broadcast stream from the broadcast transmission system 100, the decoder 320 is received. PID information is extracted from the converted broadcast data to check the version of the PID information and process it.

The process checks whether the version of the PID information is a higher version, and if the higher version is stored, updates the received PID information in the storage 350, and discards the higher version.

In this case, the process of determining whether the version of the PID information is a higher version may be performed by comparing the version of the previous PID information previously stored in the storage 350.

In addition, the event specified in the system includes both a predetermined time period, an idle time during which the operation of the digital broadcast receiving device 300 is not performed, and a real time case during the booting of the digital broadcast receiving device 300. It may include.

3 is a diagram illustrating in detail the data packet structure of a broadcast stream according to an embodiment of the present invention.

In general, the packet structure of a broadcast stream is largely composed of data DATA and a header H. The data DATA contains information of actual data such as a video stream, an audio stream, and a general data stream constituting each program. The header H includes a PSI section.

Detailed description of the structure of the header H, the header (H) is a synchronization signal (1H), transmission error indicator (2H), data unit start indicator (3H), transmission priority (4H), PSI section The position and additional information of various streams included in the data DATA such as (5H) are contained.

Of these, the information contained in the PSI section 5H is not only represented in the storage 350 to the EPG, but also used as reference material for channel zapping to influence channel switching.

That is, among the information contained in the PSI section 5H, a plurality of programs, audio streams, video streams, general data streams, and PMT (Program Map Tale) information having APID, VPID, and DPID information of each stream are included. By using the above, channel switching can be performed quickly.

Therefore, the digital broadcast reception apparatus 300 according to the embodiment of the present invention downloads the PID information of the broadcast data from the broadcast transmission system 100 in advance when an event occurs, and performs channel switching within itself with this data. According to this, it is not necessary to receive data from the transmitting side through the Internet 200 when channel zapping, and thus, data processing delay time can be shortened, and thus channel zapping time can be shortened.

Hereinafter, a method of shortening a channel zapping time and a channel switching method using the aforementioned digital broadcast reception device 300 will be described.

4 is a flowchart illustrating a method for shortening channel zapping in an IPTV system according to an exemplary embodiment of the present invention, and FIG. 5 is a flowchart illustrating a process of attempting channel zapping with reference to the method of FIG. 4.

Referring to FIG. 2, when the digital broadcast reception device 300 boots the system for an initial operation or when a predetermined time is reached, the digital broadcast reception device 300 does not perform any operation of the digital broadcast reception device 300 in real time. When an event occurs, such as an idle time that is not made, data is requested to the broadcast transmission system through the version check and the control unit 340, and in response thereto, an encoded broadcast stream is received from the broadcast transmission system (S110 and S120).

Thereafter, the received broadcast stream is demultiplexed through the demux 310 and the decoder 320 and then decoded (S130).

Here, the broadcast stream through demultiplexing in the demux 310 may be divided into an audio stream, a video stream, a general data stream, and a PSI section having PID information of these streams.

In this case, since the separated PSI section includes PID information necessary for channel zapping, the channel PSI section influences channel zapping.

Thereafter, the digital broadcast reception device 300 extracts PID information from the decoded PSI section and checks the version of the PID information (S140).

As a result of the check, if the version of the PID information is higher than the version of the pre-stored PID information, the recently received PID information is stored in the storage to automatically update (S150 to S170).

On the contrary, if the version of the PID information is not higher than the previously stored version of the PID information, the recently received PID information is discarded (S150 and S180).

The pre-stored PID information refers to PID information received just before the latest reception, and may be data updated through a version check. The pre-stored PID information is built up in the storage of the digital broadcast receiver.

Subsequently, when a channel switch is input by a user's request, the digital broadcast reception device may operate as shown in FIG. 5.

That is, when a user selects a channel to be switched and a channel switching request is input from the user, the controller in the digital broadcasting reception apparatus first searches for PID information corresponding to the input channel number by referring to the PID information previously stored in the storage. (S210, S220).

Thereafter, PID information corresponding to the channel number is extracted from the data stored in the storage, and channel switching is performed based on the extracted PID information (S230 and S240).

At this time, since the position information of the audio data and the video data corresponding to the channel number are mapped to the PID information, the channel information can be quickly changed by quickly parsing the corresponding data.

In other words, when the user moves the cursor to search for a channel and finds a desired channel, the user selects the channel. If you don't like the channel where the cursor is located, the user continues to move the cursor to search for the channel. Whenever the channel where the cursor is located changes, the video / audio data about the program being broadcast on the corresponding channel is output. In the present embodiment, the channel zapping time can be greatly shortened by parsing audio data and video data of a corresponding channel with reference to PID information stored in the digital broadcast receiving apparatus.

Thus, in this embodiment, it is considered that the issue of channel zapping time in IPTV has been largely solved. The current technology of IPTV has been a major technical issue in which the delay is greater than the zapping time when the channel is switched to the user in the existing DTV service. It was possible to increase.

Although embodiments of the present invention have been described above with reference to the accompanying drawings, those skilled in the art to which the present invention pertains may implement the present invention in other specific forms without changing the technical spirit or essential features thereof. I can understand that.

Therefore, since the embodiments described above are provided to completely inform the scope of the invention to those skilled in the art, it should be understood that they are exemplary in all respects and not limited. The invention is only defined by the scope of the claims.

1 is a diagram illustrating an apparatus for shortening a channel zapping time in an IPTV system according to an exemplary embodiment of the present invention.

2 is a diagram illustrating a configuration of a digital broadcast reception device according to an embodiment of the present invention.

3 is a diagram illustrating in detail the data packet structure of a broadcast stream according to an embodiment of the present invention.

4 is a flowchart illustrating a method for shortening channel zapping in an IPTV system according to an embodiment of the present invention.

5 is a flowchart illustrating a process of attempting channel zapping with reference to the method of FIG. 4.

Claims (10)

A demux for demultiplexing a broadcast stream encoded and provided by a transmitter and separating the broadcast stream into compressed broadcast data; A decoder which decodes the data output from the demux and converts the data into broadcast data; Graphic module for converting the broadcast signal converted by the decoder into a graphic signal for outputting Request to receive a broadcast stream provided from the transmitting side when a predetermined event occurs before a user's channel switching request, and after receiving the broadcast stream, extract PID (Program IDentifier) information from the broadcast data converted through the decoder. A version check and control unit which checks a version of the PID information, processes it, and performs a channel switch using the prestored PID information when a channel switch request is made from a user; And Storage for storing the PID information processed by the version check and the control unit in advance Apparatus for reducing channel zapping time in an IPTV system comprising a. delete The method of claim 1, The version check and control unit, If the version of the PID information is a higher version, the PID information is stored and updated, and if the version of the PID information is not higher than the previously stored previous PID information, discarding the channel zapping time in the IPTV system, characterized in that discarded Device. The method of claim 1, The broadcast stream, The audio and video streams of that content, and And a Program Specific Information (PSI) section having PID information of the audio and video streams. The method of claim 1, The event may include at least one of an idle time and a real time in which an operation of the device is not performed during a predetermined time period during booting of the device receiving the broadcast stream. A device for reducing channel zapping time in an IPTV system. Receiving a broadcast stream encoded and provided at a transmitting side when a preset event occurs before a user's channel switching request; Demultiplexing and decoding the received broadcast stream; Extracting PID (Program IDentifier) information from the decoded and output data and checking a version of the PID information; If the version of the PID information is a higher version, storing in the storage and automatically updating the PID information before the user channel switching request; And Discarding the received PID information if the version of the PID information is not higher than the previously stored previous PID information. A method for reducing channel zapping time in an IPTV system comprising a. The method of claim 6, The event may include an idle time and a real-time case in which an operation of the device is not performed during a predetermined time period during booting of a device receiving the broadcast stream. To reduce channel zapping time in a network. The method of claim 6, The data output by demultiplexing is The audio and video streams of that content, and And a program specific information (PSI) section having PID information of the audio stream and the video stream. Receiving a broadcast stream when a preset event occurs before a user's channel switching request; Extracting PID (Program IDentifier) information from the received broadcast stream to check a version of the PID information, and pre-store PID information of a higher version of pre-stored PID information and the extracted PID information; Inputting a channel switch request by a user; Retrieving the input channel switch signal from the pre-stored program specification information (PSI) and extracting PID information corresponding to the channel switch signal; And Performing channel switching with reference to the extracted PID information Channel switching method in the IPTV system comprising a. The method of claim 9, And the PID information is automatically updated to a higher version through the broadcast stream receiving step and pre-storing the higher version PID information.

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