KR101351040B1 - Method for transmitting a content, broadcasting receiver and method for receiving a broadcasting signal - Google Patents

Abstract

The present invention relates to a content data transmission method, a broadcast receiver and a broadcast reception method. The present invention has the effect of immediately watching the buffered service by buffering at least one service stream. When buffering a service stream of a specific channel, it is possible to reduce the time required to change the channel to the buffered channel, and when one content can be selected in a scene unit, a desired scene among the contents can be buffered and viewed.

DTV, IPTV

Description

Method for transmitting a content, broadcasting receiver and method for receiving a broadcasting signal}

The present invention relates to a content data transmission method, a broadcast receiver and a broadcast reception method, and more particularly, to a content data transmission method, a broadcast receiver and a broadcast reception method using an Internet protocol.

Conventional broadcast receivers are serviced in such a manner that content produced by a broadcaster is transmitted through a radio wave transmission medium such as terrestrial, cable, or satellite broadcasting, and a user views the receiver through a receiver capable of receiving the respective delivery media. .

However, as digital-based digital broadcasting technology has been developed and commercialized in existing analog broadcasting, real-time broadcasting, contents on demand, games, and news using Internet networks connected to homes in addition to existing radio waves or wired cable media. It is now possible to provide a variety of content services to the user.

An example of content service provision using the Internet network is IPTV (Internet Protocol TV). The IPTV transmits various information services, video contents, and broadcasts through an internet network and provides them to the receiver of the user. The Internet network can be implemented on various types of networks such as an optical fiber network, a coaxial cable network, a fiber to the home (FTTH), a telephone network, and a wireless network based on IP (Internet Protocol).

In the case of the service using the Internet network as described above, unlike general terrestrial broadcasting, the interactivity may be added, and the user may watch the content service that he / she wants to see at a convenient time.

However, in the case of the service using the Internet network, all broadcasts are not transmitted to the receiver of the user due to a bandwidth limitation. Therefore, when changing the channel, the user must go through a step of requesting the service provider for channel change, which causes a problem of slowing down the channel change rate.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a content data transmission method, a broadcast receiver, and a broadcast reception method which can reduce the time required for channel change.

In the method of transmitting content data according to the present invention, transmitting a service provider discovery record including information on a service provider, and transmitting a service discovery record including information on a service provided by the service provider. And transmitting a service stream of at least one buffered channel and a service stream of a channel which is requested to display among the services.

In another aspect, the method for transmitting content data according to the present invention includes transmitting a service provider discovery record including information on a service provider, and transmitting a service discovery record including information on a service provided by the service provider. And transmitting a stream of the portion to be displayed and a stream of the at least one buffered portion to be displayed in a service for dividing the content into at least one or more portions.

In a broadcast receiving method according to the present invention, receiving a service discovery information packet including information on a service and extracting information included in the packet, storing the information extracted from the packet, and using the stored information Creating a channel map, and using the channel map, receiving and displaying a service stream of a channel requested for display on a screen, and receiving and buffering a service stream of at least one buffered channel.

In another aspect, the broadcast receiving method according to the present invention includes receiving a service discovery information packet including information on a service and extracting information included in the packet, storing the information extracted from the packet, and storing the stored information. Creating a channel map using the; and Receiving and displaying a stream of the currently displayed portion of the content service divided into at least one portion using the channel map on the screen, Receive a stream of at least one buffered portion Buffering.

The broadcast receiver according to the present invention includes a service discovery manager for receiving a service discovery information packet including information on a service and extracting information included in the packet, a service information database unit for storing the information extracted from the packet, And a channel manager for creating and managing a channel map using the stored information, and an application / UI manager for controlling to receive and buffer a service stream of at least one buffered channel using the channel map.

In another aspect, the broadcast receiver includes a service discovery manager for receiving a service discovery information packet including information on a service and extracting information included in the packet, and service information storing information extracted from the packet. A database manager, a channel manager for creating and managing a channel map using the stored information, and a channel manager for receiving and buffering a stream of at least one buffered part of a content service divided into at least one or more parts using the channel map. Contains the application / UI manager.

According to the content data transmission method, the broadcast receiver, and the broadcast reception method using the Internet protocol of the present invention, the time required for channel change can be reduced, so that the user can immediately watch the broadcast of the desired channel. In addition, when one content can be selected in units of scenes, there is an effect of selecting a desired scene among the contents and immediately watching the content.

BRIEF DESCRIPTION OF THE DRAWINGS The objects, features and advantages of the present invention will become apparent from the following detailed description of embodiments with reference to the accompanying drawings. In addition, although the term used in the present invention is selected as a general term that is widely used at present, in some cases, there is a term arbitrarily selected by the applicant. In this case, the meaning is described in detail in the description of the present invention. It is to be understood that the present invention should be grasped as a meaning of a term other than a name.

Operation of the content data transmission method, the broadcast receiver and the broadcast reception method according to the present invention configured as described above will be described in detail with reference to the accompanying drawings.

An Internet Protocol TV (IPTV) system, which is an example of a system that can provide various contents using the Internet network, can be largely divided into a server, a network, and a receiver.

The servers of the IPTV are servers that perform various functions such as service discovery and selection server, streaming server, contents guide information server, customer information server, and payment information server. It can be configured as.

Among the servers, the streaming server transmits video data encoded in the stored Moving Picture Experts Group (MPEG) 2, MPEG4, etc. to the user through a network. As a protocol for the transmission, a Real-Time Transport Protocol (RTP), a RTP Control Protocol (RTP), or the like may be used.

In case of using Real-Time Streaming Protocol (RTSP), video stream playback can be controlled to some extent through a function called network trick play such as pause, replay, and stop. . The protocols are examples and other real time transmission protocols may be used depending on the implementation.

The content guide information server is a server that provides information on the various contents provided. The content guide information is information corresponding to electronic program guide (EPG) information and includes various information about content. The content guide information server stores content guide information data, and provides the stored data to the receiver.

The information server related to service discovery and selection among the servers provides the receiver with access information and playback information for servers providing various content services such as broadcasting, contents on demand (COD), and games.

The network system consists of an internet based network and gateways. The Internet-based network may use various types of networks such as an optical cable network, a coaxial cable network, a fiber to the home (FTTH), a telephone network, a wireless network, and the like based on IP. In addition to general data transfer, the gateway may perform multicast group management and quality of service (QoS) management using protocols such as Internet Group Management Protocol (IGMP).

A receiver of an IPTV is a receiver capable of receiving data transmitted through an internet network and providing the same to a user. The receiver includes an IPTV settop, a homenet gateway, an IPTV embedded TV, and the like.

In the case of a hybrid IPTV system, various types of contents of the Internet as well as various types of existing broadcasting contents may be provided. That is, the user can provide various broadcasting contents such as terrestrial broadcasting, cable broadcasting, satellite broadcasting, personal broadcasting, various internet video contents, data contents other than video, and the like. The contents may be provided in real time or may be provided on demand.

1 is a diagram schematically showing an IPTV system according to an embodiment of the present invention.

In terms of providing a content service, the IPTV system may be divided into a content provider (CP), a service provider (SP), a network provider (NP), and a user.

The content provider produces and provides various contents. As shown in FIG. 1, the content provider includes a terrestrial broadcaster, a cable SO, or a MSO, a satellite broadcaster, and an internet broadcaster. (Internet broadcaster) and the like.

The service provider provides a service package of contents provided by the content provider. For example, the service provider of FIG. 1 packages a first terrestrial broadcast, a second terrestrial broadcast, a cable MSO, satellite broadcast, various Internet broadcasts, and provides the same to a user.

The network provider provides a network for providing the service to a user. The user may build a home network end user (HNED) to receive the service.

Conditional access, content protection, or the like may be used as a means for protecting content transmitted from the IPTV system. As one example for the above-mentioned restriction reception or content protection, a method such as a cable card or a downloadable conditional access system (DCAS) may be used.

In order to provide content to the user, the IPTV receiver needs to find and access a server that stores content desired by the user. The receiver may access an entry point of an IPTV portal (or a system operator (SO)) provided by a network provider to find the content server. The entry point refers to a kind of connection location. The user may input an IP address / port or a Domain Name System (DNS) Uniform Resource Locator (URL) for an entry point of the IPTV portal, or select and input a pre-registered address. Alternatively, the receiver may automatically access a preselected address or the like.

The entry point of the IPTV portal provides a receiver with a service provider discovery record including information about each service provider. The service provider discovery record includes various information about a service provider, for example, service provider identification information, access information, and the like.

The receiver uses the information of the received service provider discovery record to access a server of a service provider that provides a service desired by the user. The service provider provides a service discovery record including information about content to the receiver. The service discovery record includes various information about a content service, for example, an access address of a service server that stores content.

The receiver stores the received service discovery record. The service discovery record is used to access a service server of a content provider providing content desired by a user, and receive a stream from the server. If the user wants to watch content provided by another channel (or content provided by another service server), the receiver accesses the service server of the corresponding content provider again using the information of the stored service discovery record.

When buffering at least one or more services in addition to the channel currently being viewed by the receiver, the receiver may shorten the time required to change the channel. That is, when changing from a channel currently being viewed to one of the buffered channels, the receiver may directly display the buffered content service on the screen.

If the service server provides content in units of scenes, a desired scene part may be buffered using the buffering. For example, when a content is divided into several parts based on content change or time, and the user can select and watch a specific part from the divided parts, the user may select and buffer at least one of the divided parts. Can be. When the user selects one portion of the buffered portion, the receiver may display the screen directly from the portion that is buffered.

2 is a block diagram schematically showing the configuration of a receiver according to an embodiment of the present invention. In the receiver of FIG. 2, a separate tuner or the like may be provided to receive terrestrial broadcast, cable broadcast, satellite broadcast, and the like. However, in the present invention, for the convenience of description, the description will be made mainly on the part of processing the content transmitted using the Internet network.

The receiver includes a network interface unit 202, an IP manager 204, an application / UI manager 206, a CM unit 208, a service information decoder 210, a service information database unit 212, and a service discovery manager 214. ), Service control manager 216, CAS / DRM unit 218, service delivery manager 220, demultiplexer 222, audio / video decoder 224, display unit 226, storage unit 228, system The manager 230 includes a storage medium controller 232 and a storage medium 234.

The network interface unit 202 receives packets received from the network and transmits the packets from the receiver to the network. The IP manager 204 is involved in packet forwarding from the source to the destination for the packets received at the receiver and the packets transmitted at the receiver. And classifies the received packet so as to correspond to an appropriate protocol.

The application / UI manager 206 provides a Graphical User Interface (GUI) for a user by using an On Screen Display (OSD), etc., and receives a key input from a user to perform a receiver operation according to the input. . For example, upon receiving a key input related to channel selection from a user, the key input signal is transmitted to the CM unit 208.

The CM (Channel Manager) unit 208 creates a channel map. In addition, the channel is selected using the channel map according to the key input received from the application / UI manager 206, and the service discovery manager 214 and the service control manager 216 are controlled. The CM unit 208 receives the service information of the channel from the service information decoder 210 and sets the audio / video PID (packet identifier) of the selected channel to the demultiplexer 222.

The service information decoder 210 decodes service information such as program specific information (PSI). That is, the demultiplexer 222 receives and decodes the demultiplexed PSI section, PSIP (Program and Service Information Protocol) section, or DVB-SI (Service Information) section.

The service information decoder 210 decodes the received sections to create a database of service information, and stores the database of the service information in the service information database unit 212.

The service discovery manager 214 provides information necessary to select a service provider that provides a service. Upon receiving a signal regarding channel selection from the application / UI manager 206, the service discovery manager 214 uses the information to find a service.

The service control manager 216 is in charge of selecting and controlling a service. For example, if a user selects a live broadcasting service such as a conventional broadcasting method, use IGMP or RTSP, and when selecting a service such as VOD (Vidoe On Demand), use RTSP to select and control the service. Perform The RTSP protocol may provide a trick mode for real-time streaming. The protocol is an embodiment, and other protocols may be used depending on implementation.

The packet regarding the service received through the network interface unit 202 and the IP manager 204 is transmitted to the CAS / DRM unit 218. The CAS / DRM unit 218 is responsible for conditional access system (CAS) and digital rights management (DRM).

The service delivery manager 220 is in charge of controlling received service data. For example, when controlling real-time streaming data, the RTP / RTCP (Rela-Time Transport Protocol / RTP Control Protocol) may be used. When transmitting the real-time streaming data using the RTP, the service delivery manager 220 parses the received data packet according to the RTP and transmits it to the demultiplexer 222. Then, the RTCP is used to feed back the network reception information to a server that provides a service.

The demultiplexer 222 demultiplexes the received packet into audio, video, PSI (Program Specific Information) data, and the like, and transmits the demultiplexer 222 to the video / audio decoder 224 and the service information decoder 210, respectively.

The video / audio decoder 224 decodes the video data and the audio data received at the demultiplexer 222. The video data decoded by the video / audio decoder 224 is provided to the user through the display unit 226, and the decoded audio data is provided to the user through a speaker (not shown).

The storage unit 228 stores setup data and the like for the system. A nonvolatile RAM (NVRAM) or a flash memory may be used as the storage unit. The system manager 230 controls the overall operation of the receiver system through a power source.

The storage medium controller 232 controls to store the video / audio data in the storage medium 234 or controls to read and play the data stored in the storage medium 234. The storage medium 234 receives and stores video / audio data from the video / audio decoder 224 under the control of the storage medium controller 232.

The receiver connects to the entry point of the IPTV portal and receives a packet of service provider discovery records. The network interface unit 202 transmits the received packet to the IP manager 204. The IP manager 204 checks whether the destination of the received packet is the receiver, and then transmits the packet to an appropriate manager block according to a transmission / reception protocol.

The packet containing the service provider discovery information is transmitted using a protocol relating to service discovery and selection. For example, DVB-IP is transmitted according to Service Discovery & Selection (SD & S) (or Service Discovery Protocol: SDP) protocol. Accordingly, the IP manager 204 sends a packet containing the service provider discovery information to the service discovery manager 214.

The service discovery manager 214 parses the received packet to obtain various information of an included service provider discovery record. The information is transmitted to and stored in the service information database unit 212.

The receiver may receive a packet including service discovery information from the service provider using the access information of the service provider included in the service provider discovery record. The packet including the service discovery information is transmitted and received using the SD & S (or SDP) protocol.

The packet including the service discovery information is transmitted to the IP manager 204 via the network interface unit 202. The IP manager 204 checks whether the destination of the received packet is the receiver, and then transmits the packet to the service discovery manager 214. The service discovery manager 214 obtains service discovery information included in the received packet. The information is transmitted to and stored in the service information database unit 212.

The service information database unit 212 stores and manages the received various types of information. The CM unit 208 creates and manages a channel map using various types of information stored in the service information database unit 212.

The application / UI manager 206 receives channel information corresponding to desired content from the user and controls the channel to be switched according to the channel map. That is, the channel may be switched by receiving channel information corresponding to content that the user wants to watch.

The receiver of FIG. 2 buffers at least one channel or buffers at least one scene portion in addition to the viewing channel that the user wants to watch. The buffering channel may be set through a menu.

3A is a diagram schematically illustrating a menu for setting a buffering channel according to an embodiment of the present invention. When a user request is input through an input device such as a remote controller, a keypad, a jog dial, and a touch screen provided on the screen, a setting menu as shown in FIG. 3A is displayed on the screen.

When the application / UI manager 206 has such a request, the application / UI manager 206 displays the setting menu as shown in FIG. 3A on the display unit 226 through an OSD (On Screen Display).

3A is a diagram schematically illustrating a main menu. The main menu includes video related settings, audio related settings,... And a buffering configuration menu. Video-related settings set video-related content, such as aspect ratio and picture quality, and audio-related settings set audio-related content, such as sound quality and audio channel settings. The buffering setting is configured to buffer at least one channel or the at least one scene portion described above.

3A schematically illustrates a lower menu displayed on a screen when the buffering setting menu is selected. The lower menu may be divided into a channel buffering setting and a scene buffering setting.

The adjacent channel buffering, the previous viewing channel buffering, the reserved viewing channel buffering, and the user preferred channel buffering are menus for buffering at least one channel other than the current viewing channel. In addition, 'scene buffering' is a menu for setting buffering of at least one scene part when content is provided in a scene unit.

When setting adjacent channel buffering, the receiver buffers the adjacent channel of the channel currently being watched. For example, when currently watching channel 3, the previous number channel and the next number channel of the channel 3 are buffered. The user may select a previous number or next number channel by using up and down buttons, such as a remote controller, and immediately view the contents of the buffered channel.

When setting the previous viewing channel buffering, the receiver buffers the channel previously watched by the user. For example, when watching channel 3 and watching channel 5 before, the channel 5 is buffered. The user can immediately watch channel 5 previously watched by using the previous viewing channel button or the back button.

When the reserved viewing channel buffering is set, the receiver buffers a channel that the user has previously set reserved viewing. The reservation viewing can be set using another reservation watching menu or the like, and when a user changes a channel to the reservation watching channel, the content can be immediately viewed. However, if there is no reservation viewing setting, a message, etc. indicating that the reservation viewing setting is not set may be displayed on the screen.

3B is a diagram schematically illustrating a menu for selecting a reserved viewing channel according to an embodiment of the present invention. 3B, 100, 101, 102,... 205 represents a channel number of each channel. The receiver displays the viewable channel on the screen as described above, and the user may reserve and set a specific channel among the viewable channels. In FIG. 3B, channels 102, 202, and 205 are reserved and viewed, respectively. Therefore, a service corresponding to channel 102, 202, and 205 may be buffered.

In the example of FIG. 3B, the reserved viewing channel setting menu is schematically configured, but instead of the menu, the reserved viewing channel may be set in a guide screen such as an electronic program guide (EPG) or a broadband content guide (BCG).

If user preference channel buffering is set, the receiver buffers the user's preferred channel. The user preference channel may be preset by the user or may be automatically set by analyzing a user's channel viewing pattern. For example, the preferred channel may be set in advance in the menu of FIG. 3B or a guide screen such as EPG or BCG. Alternatively, the channel viewing pattern of the user may be analyzed to automatically set a channel that the user frequently watches or a channel of the genre (ex, sports, drama, etc.) that the user frequently watches as a favorite channel.

When setting the scene buffering, the receiver buffers at least one or more scene parts in the content provided in units of scenes. The user selects at least one or more scenes of a specific scene of the content, and the receiver buffers the selected scene portion. If the content is not provided in units of scenes, a message indicating that the function is not supported may be displayed on the screen.

In each of the above examples, the number of buffered channels or the number of scenes may vary depending on the implementation in consideration of a buffering memory. In addition, the above-described menu screen, menu form, menu name, and the like are exemplary embodiments, and the spirit of the present invention is not limited to the above form, name, and the like.

When the buffering channel or the buffering scene is set as described above, the application / UI manager 206 accesses an address that can receive the contents of the channel or the scene by using the channel map.

A packet including data about the buffering channel or the buffering scene is transmitted to the demultiplexer 222 through the IP manager 204, the CAS / DRM unit 218, and the service delivery manager 220. The application / UI manager 206 sets the demultiplexer 222 with the PID of a packet including data on the buffering channel or the buffering scene. The demultiplexer 222 stores and buffers A / V data of a packet having the set PID in the storage medium 234 under the control of the storage medium controller 232. In the above example, the buffering is performed in the storage medium 234. However, the memory for buffering may be provided instead of the storage medium 234 or may be buffered using a transmission address of a service.

The buffering space may vary according to an embodiment, and the buffering space is determined in consideration of network conditions, the space of the storage medium, the number of buffered channels, and the like. For example, if the network conditions are bad, you can increase the buffering space. If the network conditions are good, you can reduce the buffering space or allow more channels or scenes to be buffered in the same space. The buffering space or the number of buffering channels as described above may be set by the user.

When the user selects one of the buffered channels or scenes and inputs a viewing command, the application / UI manager 206 immediately starts the video / audio decoder 224 from the data being buffered to the storage medium 234. Control to be decoded.

If a user selects a channel or a scene that is not buffered and inputs a viewing command, the user accesses an address that can receive content or a scene of the corresponding channel using a channel map and receives data.

4 is a flowchart schematically illustrating a signal processing process according to an embodiment of the present invention. 4 illustrates the flow and sequence of signals between a service server and a service provider server, an entry point of an IPTV portal, and a receiver. The service server refers to a service server of a provider.

The receiver accesses the entry point of the IPTV portal provided by the network provider (S400). The IPTV portal may check subscription information of the connected receiver. That is, the subscriber information may be checked to determine whether the receiver is provided with a service associated with the IPTV portal.

The entry point of the IPTV portal transmits a service provider discovery record including various information about the network provider or the service provider to the receiver (S410).

The receiver stores various information included in the received service provider discovery record (S420). The information may include service provider identification information, service provider access information, and the like.

The receiver accesses the server of the service provider using the access information of the service provider among the information (S430). If there is a connection from the receiver, the server of the service provider transmits a service discovery record including various information about content to the receiver (S440).

The receiver receives the service discovery record and stores various information stored in the record (S450). The information may include content provider identification information, content source identification information, content content identification information, characteristic information of content data, content provider access information, and the like. The receiver may create a channel map using the above information.

When the user inputs channel information of content to be viewed, the receiver accesses the service server of the corresponding content by using the stored information and the channel map. When the user sets the buffering channel or the buffering scene, the user accesses the access address of the buffering channel or the buffering scene (S460). The service server starts a streaming service by transmitting a data stream of the service to the connected receiver (S470). The receiver displays the contents of the data received from the service server by the user on the screen, and buffers and stores the contents of the buffered channel or scene (S480).

Therefore, when the receiver requests a change to the buffered channel or scene from the user, the receiver may directly display the buffered portion on the screen.

As described above, the contents of the present invention can be used not only in an IPTV system using an Internet protocol, but also in a system requiring a separate request or changing time in addition to the IPTV system.

It is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

1 is a diagram schematically showing an IPTV system according to an embodiment of the present invention.

2 is a block diagram schematically showing a configuration of a receiver according to an embodiment of the present invention.

3A is a diagram schematically illustrating a menu for setting a buffering channel according to an embodiment of the present invention.

3B is a diagram schematically illustrating a menu for selecting a reserved viewing channel according to an embodiment of the present invention.

4 is a flowchart schematically illustrating a signal processing process according to an embodiment of the present invention.

DESCRIPTION OF THE REFERENCE NUMERALS

202: network interface unit 204: IP manager

206: Application & UI Manager 208: CM Department

210: service information decoder 212: service information database unit

214: service discovery manager 216: service control manager

218: CAS / DRM part 220: service delivery manager

222 demultiplexer 224 audio / video decoder

226 display unit 228 storage unit

230: system manager 232: storage medium control unit

234: storage medium

Claims (18)

delete delete delete delete delete delete In the digital broadcast receiving method through the Internet, Receiving a service discovery information packet which is service information (SI) and extracting service information included in the packet; Storing service information extracted from the packet, and creating a channel map using the stored service information; And Receiving and displaying a data stream of a service of a channel currently requested for display on the screen by using the channel map, and receiving and buffering and storing a data stream of a service of a preset buffering setting channel. Digital broadcast reception method. The method of claim 7, wherein The buffering setting channel, Digital broadcast receiving method characterized in that the adjacent channel of the display request channel The method of claim 7, wherein The buffering setting channel, Digital broadcast receiving method characterized in that the channel previously watched The method of claim 7, wherein The buffering setting channel, Digital broadcasting receiving method characterized in that the user reserved for viewing the channel The method of claim 7, wherein The buffering setting channel, Digital broadcast reception method characterized in that the user preference channel In the digital broadcast receiving method through the Internet, Receiving a service discovery information packet which is service information (SI) and extracting service information included in the packet; Storing service information extracted from the packet, and creating a channel map using the stored service information; And Using the channel map, receiving and displaying a data stream of a currently displayed portion of a service for dividing contents into at least one or more portions on a screen, and receiving and buffering and storing a data stream of a predetermined buffering setting portion Digital broadcast receiving method comprising a. 13. The method of claim 12, The buffering setting channel, Digital broadcast receiving method characterized in that the adjacent channel of the display request channel 13. The method of claim 12, The buffering setting channel, Digital broadcast receiving method characterized in that the channel previously watched 13. The method of claim 12, The buffering setting channel, Digital broadcasting receiving method characterized in that the user reserved for viewing the channel 13. The method of claim 12, The buffering setting channel, Digital broadcast reception method characterized in that the user preference channel A service discovery manager for receiving a service discovery information packet which is service information (SI) and extracting service information included in the packet; A service information database unit for storing service information extracted from the packet; A channel manager for creating and managing a channel map using the stored service information; And An application / UI manager for controlling to receive and display a data stream of a service of a channel currently requested for display on the screen by using the channel map, and to receive and buffer a data stream of a service of a preset buffering setting channel; Digital broadcast receiver, characterized in that. 18. The method of claim 17, And a storage unit for receiving and storing a data stream of a service of the buffering setting channel.

Images