KR20060082326A - Automatic setting method of channel for digital tv - Google Patents

Abstract

The present invention relates to an automatic channel setting method in a digital broadcast receiver, comprising the steps of sequentially scanning a broadcast signal corresponding to each digital broadcast channel, determining whether a broadcast signal corresponding to a broadcast channel is received, If it is received, determining whether at least one of a video signal and an audio signal is detected in the broadcast signal. If the audio signal is detected, the result is determined as an unscrambled clear channel, and information about the channel is stored in a memory. Characterized in that it comprises a step. As a result, since a program map is created so that only the CREE channel can be viewed with only one selection for automatic channel setting, it is possible to prevent the consumption of time and effort from the viewer's point of view, thereby enhancing the convenience of the viewer. In addition, during automatic channel setting, it is possible to accurately select a scrambled channel by determining whether a broadcast signal is scrambled through multiple steps.

Digital broadcasting channel, broadcasting signal, scrambled, demux, audio signal, video signal

Description

Automatic channel setting method in digital broadcasting receiver {AUTOMATIC SETTING METHOD OF CHANNEL FOR DIGITAL TV}

1 is a block diagram of a broadcast receiver according to the present invention;

2 is a flowchart illustrating a channel setting process using an automatic channel setting method according to the present invention;

3 is a detailed flowchart illustrating a process of selecting a scrambled channel in the automatic channel setting process of FIG. 2.

Explanation of symbols on the main parts of the drawings

10: Tuner 20: Demux

31: audio buffer 33: video buffer

35: data buffer 40: decoder

50: control unit 60: memory

70: conditional access system module

The present invention relates to an automatic channel setting method in a digital broadcast receiver. More specifically, the present invention relates to a method for automatically setting a channel according to whether a broadcast signal is demultiplexed and whether a decoded broadcast signal includes a video signal and an audio signal. To automatically skip a scrambled channel when searching for a channel and to prevent an error from occurring in determining a scrambled channel through a multi-step determination process. will be.

As digital broadcasting including digital cable broadcasting, digital satellite broadcasting, and digital terrestrial broadcasting has become active, the number of channels that can be watched has increased to more than 100, and the number of such channels is increasing.

In order to watch the necessary channels among the digital broadcasting channels, the broadcasting fee should be stored separately from the public broadcasting company, and the digital broadcasting company uses the broadcasting fee to provide a quality broadcasting program that is excellent in quality and differentiated from other broadcasting programs. Will be produced. In order to protect the broadcast program produced in this way and to protect the subscribers' right to watch, the digital broadcasting company utilizes a conditional access system (CAS) so that only the subscriber can watch the program.

A conditional access system is a system in which a digital broadcasting company scrambles and transmits a broadcast signal using its own encryption system, and only subscribers who have received permission by receiving subscriptions can descramble and view a program. . As a scramble method, a special signal is put into a broadcast signal or a sequence of scanning lines is used.When scrambled, the image is corrected on a TV receiver such as shades are reversed and colors of the screen are mixed or lines are drawn on the screen. Does not appear. Such scramble can be released using a scramble dedicated decoder.

On the other hand, in general, viewers need to watch only some channels among many channels, and thus, viewers only watch the corresponding channels by contracting with some digital broadcasters. However, since the viewer only contracts with some digital broadcasters, the number of scrambled channels that cannot be viewed is more common than the clear channel, which is a channel that viewers can watch, and the number of digital broadcasters increases. As the number of channels increases, the number of scrambled channels that the viewer encounters will increase. Therefore, when a viewer searches for a channel in order to watch a digital broadcast, since the scrambled channel is searched more than the cree channel, a time for searching for a viewable clear channel increases, causing inconvenience to the viewer.

Accordingly, there is a need for a function of skipping a scrambled channel when a viewer searches for a channel. However, the conventional set-top box for receiving digital broadcasts is provided with only a channel skip program that can skip a channel for which a broadcast signal is not received when a viewer searches for a channel, and has a function of skipping a scrambled channel. It is not yet provided. Therefore, in order to skip the scrambled channel, the viewer needs to store the clear channel in the memory using the Add key and the Delete key while directly downing the channel. However, when there are many channels, viewers need a lot of time and effort to check the channels one by one, which brings inconvenience to viewers.

In order to improve this problem, the Republic of Korea Patent No. 441337 "Automatic Channel Setting Method in Digital Broadcast Receiver" (hereinafter referred to as an earlier application), the tuning data for the channel and each service while scanning the digital broadcast channel sequentially These data are automatically detected, and only the tuning data of the descrambleable broadcast channel and service are selected and stored in the memory. At this time, the tuning data for the corresponding channel and each service is scrambled from the program map table (PMT) information and the service description table (SDT) information included in the service information (SI) information. Tuning data for the type and broadcast type of each service. That is, the prior application selects and stores only tuning data of broadcast channels and services that can be descrambled by the digital broadcast receiver based on information on the scramble type and broadcast type and stores them in a memory. Accordingly, it is possible to prevent the digital broadcast receiver from storing unnecessary tuning data for a broadcast channel and a service providing a broadcast program that cannot be processed.

However, when using the method of screening the scrambled channel according to the scrambled type used in the prior art, if the information about the scrambled type included in the SI information is not correct, skip the unscrambled channel or memory the scrambled channel Can cause errors to be stored in In particular, in the case of a small digital broadcaster other than the airwaves, since the management is neglected due to the large number of channels, the SI information may be unstable, so there is enough room for such an error.

Accordingly, when screening the scrambled channel, the information about the scrambled type included in the SI information, not information that is not likely to cause an error, for example, whether the received digital broadcast signal is being processed, the video signal and the audio signal It is necessary to find a way to select the scrambled channel using whether or not there is.

Accordingly, an object of the present invention is to automatically skip a scrambled channel when searching for a channel by determining whether a scrambled channel is determined according to whether the broadcast signal is demultiplexed and whether the decoded broadcast signal includes a video signal and an audio signal. It is to provide an automatic channel setting method in the digital broadcast receiver to prevent an error occurs in the determination of the scrambled channel through a multi-step determination process.

The configuration of the present invention for achieving this object comprises the steps of sequentially scanning a broadcast signal corresponding to each digital broadcast channel; Determining whether a broadcast signal corresponding to the broadcast channel is received; If the broadcast signal is received, determining whether at least one of a video signal and an audio signal is detected in the broadcast signal; And determining that the audio signal is not scrambled as a result of the determination, and storing information about the channel in a memory.

The determining of whether the broadcast signal is received may be determined by whether a tuner for tuning the broadcast signal is operated.

If the broadcast signal is detected, the method may further include determining whether the broadcast signal is divided into a video signal and an audio signal.

Whether the video signal and the audio signal are separated may be determined by demux operation.

The step of determining whether the video signal and the audio signal are detected is the step of determining the decoded video signal and the audio signal; As a result of the determination, if the video signal and the audio signal are simultaneously detected, the method may further include determining the clear channel and storing the same in the memory.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram of a digital broadcast receiver to which an automatic channel setting method according to the present invention is applied.

In general, the digital broadcast receiver includes a tuner 10, a demux 20, an audio buffer 31, a video buffer 33, a data buffer 35, a decoder 40, a memory 60, a conditional access system module. 70, the control unit 50 is included.

The tuner 10 receives a digital broadcast signal in synchronization with a digital broadcast frequency, and the digital broadcast signal may include a plurality of broadcast signals for a plurality of minor channels, which are subchannels included in one PTC channel. In order to distinguish each of these broadcast signals, a unique identifier is assigned to the broadcast signal for each minor channel, which is a PID (Packet Identifier). The PID includes a PCR PID (Program Clock Reference), a video PID, and an audio PID. Here, PCR is data for simultaneous output of a video signal and an audio signal, and a difference occurs in the output of the video signal and the audio signal. This data is referred to to prevent misalignment.

On the other hand, broadcast signals are multiplexed according to the AC-3 or MPEG system standard for audio signals, and multiplexed according to the MPEG system standard for video signals. Among these, the multiplexing by MPEG system is a method of combining one or more audio, video, and data streams into a single or multiple stream in a form suitable for storage or transmission. The transport stream (TS) multiplexing method and the program stream (PS) multiplexing Are classified in a manner. The broadcast signal during multiplexing by the MPEG system includes timing information (DTS, PTS) related to decoding and reproduction of video data and audio data, and timing information (PCR and SCR) related to transmission of the stream itself.

The demux 20 receives the MPEG-2 transport stream (TS) packet data, which is transmitted by multiplexing audio and video data in the MPEG-2 format on the transmitting side, and performs audio and video in real time. Demultiplexed into an elementary stream (ES) and provided to the audio and video decoder 40, respectively. At this time, the audio and video elementary streams are temporarily stored in the audio buffer 31 and the video buffer 33 before being provided to the audio and video decoder 40.

The decoder 40 decodes the audio and video elementary streams into video signals and audio signals before transmission, and the restored video signals and audio signals are output through the receiver and the speaker, respectively.

On the other hand, the memory 60 stores various kinds of information necessary for the operation of the digital broadcast receiver, and a program map in which the information on the channel that the viewer can watch is stored in the form of a map. The program map includes information on the viewable clear channel except for a channel for which a broadcast signal is not received and a scrambled channel that cannot be viewed by a viewer. Based on such a program map, only the clear channel is searched except for the scrambled channel which the viewer cannot watch when searching for the channel.

If the received audio signal and the video signal are scrambled, the conditional access system module 70 processes the scramble according to the user's authentication and enables viewing, and the conditional access system is connected to the controller 50 through the interface 75. do.

On the other hand, the controller 50 controls the operation of each operating element in accordance with user selection from the outside, and serves to monitor the operation state. For example, the controller 50 operates the tuner 10, the demux 20, the limited reception system module 70, and the like when the power is applied, and the tuner 10 operates by tuning to the broadcast signal of the selected channel. Whether the video signal and the audio signal are demultiplexed through the demux 20, and whether the audio signal and the video signal are output through the decoder 40 is monitored. In addition, the controller 50 determines whether the corresponding channel is scrambled by grasping the operation and output of each operation element according to a user's selection, and controls a channel automatic setting process of creating a program map according to the determination result.

Through the automatic channel setting process, the controller 50 may determine whether to scramble the corresponding channel by checking the broadcast signal in multiple stages. First, the controller 50 determines reception of a broadcast signal according to whether the tuner 10 is operated, and if it is determined that the broadcast signal has been received, detects whether the demux 20 has been operated to determine whether the broadcast signal is demultiplexed. . In addition, when the demux 20 operates, the controller 50 determines whether there is a video signal and an audio signal decoded and output through the decoder 40. At this time, the controller 50 stores the video signal and the audio signal together and stores only the audio signal in the program map of the memory 60 when the audio signal exists. This is because the controller 50 recognizes a television broadcast channel when the video signal and the audio signal exist together, and recognizes it as a radio broadcast channel when only the audio signal exists. On the other hand, if only the video signal is present, it is very likely that the audio signal that is not essential to the video signal is a scrambled broadcast signal. Therefore, the controller 50 determines that the received broadcast signal is a television broadcast signal or scrambled memory ( 60) do not store.

The digital broadcast receiver having such a configuration forms a program map consisting of only the viewable clear channel using the automatic channel setting method as shown in FIG.

First, when the power is applied and the viewer selects the operation of the automatic channel setting process, the controller 50 operates the tuner 10, the demux 20, and the decoder 40, and broadcast signals corresponding to each broadcast channel. Scan sequentially (S100). At this time, a broadcast signal may or may not be received for each broadcast channel depending on whether a broadcaster is providing a program. Scanning the broadcast channel as described above, the controller 50 determines whether there is a broadcast signal in each broadcast channel, and the controller 50 determines whether or not the tuner 10 performs an operation of tuning the broadcast signal. Determine the presence (S110).

If it is determined that a broadcast signal is received through a specific channel, the controller 50 determines the frequency band of the received broadcast signal to determine whether it is a digital broadcast signal or an analog broadcast signal (S120). Since C is a clear channel that can be viewed, information about a corresponding broadcast channel is stored in a program map of the memory 60 (S125).

In the case of a digital broadcast signal, the controller 50 determines whether there is a minor channel for the corresponding PTC channel, and if there is a minor channel, determines whether or not a scrambled channel is present for each minor channel (S130). To determine whether it is a scrambled channel, as shown in FIG. 3, the controller 50 determines whether the received broadcast signal is demultiplexed into an audio and video elementary stream (ES) through the demux 20. In this case, the controller 50 determines whether the demux 20 is operated (S130-1) or determines whether a broadcast signal is present based on whether a PCR PID, a video PID, and an audio PID exist. .

If it is determined that the broadcast signal is present through the demux 20, the controller 50 determines whether an actual audio signal and a video signal exist. To determine whether the audio signal and the video signal exist, the audio signal, Decoding of the video signal to the decoder 40 must be preceded (S130-2). When the decoding is completed by the decoder 40, the controller 50 determines whether an audio signal and a video signal exist (S130-3). As a result of the determination, when the video signal and the audio signal exist together, the controller 50 determines that the received broadcast signal is a television broadcast signal and is a scrambled channel that is not scrambled (S130-5). Then, the controller 50 stores information on the corresponding minor channel, for example, information on the PTC channel of the corresponding minor channel, PCR PID, video PID, audio PID information of the minor channel, and the like. Store in the map (S135). On the other hand, if there is only an audio signal (S130-4), the controller 50 determines that the received broadcast signal is a radio broadcast signal and is a scrambled non-scrambled channel, and the information on the corresponding channel is stored in the memory 60. The program map is stored (S135). After storing the information about the clear channel in the program map of the memory 60, the controller 50 determines whether there is another minor channel in the PTC channel including the corresponding minor channel. If there is another minor channel, the controller 50 determines whether the scrambled channel is the same as the above-described S130-1 to S130-6 (S140). When the scramble determination is completed for all minor channels of the PTC channel, the controller 50 determines whether the next PTC channel exists, and if the next PTC channel exists, the process returns to step S100 and repeats the scramble determination process ( S150).

On the other hand, if there is only a video signal and no audio signal, the controller 50 determines that the channel is a scrambled channel, and as described above, moves to the next minor channel or PTC channel and the above-described S130-1 to The process of S130-6 is repeated.

As described above, in the automatic channel setting method, the broadcast signal is received according to the viewer's selection, whether the broadcast signal is demultiplexed, whether the actual audio signal and the video signal exist, and correspondingly to the received broadcast signal. It is automatically determined whether the broadcast channel is scrambled. Accordingly, since a program map is created so that only the CREE channel can be viewed with a single selection for automatic channel setting, it is possible to prevent the consumption of time and effort from the viewer's point of view, thereby facilitating the viewer's convenience. In addition, during automatic channel setting, it is possible to accurately select a scrambled channel by determining whether a broadcast signal is scrambled through multiple steps. Therefore, although the scrambled channel is set to be skipped as in the prior art, it is possible to prevent the scrambled channel from being stored in the program map or the clear channel from being skipped due to the inaccuracy of the SI information.

Further, in the detailed description of the present invention, specific embodiments have been described, which should be taken as exemplary, and various modifications may be made without departing from the technical spirit of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the claims below, but also by the equivalents of the claims.

As described above, according to the present invention, since the program map is created so that only the CREE channel can be viewed with only one selection for automatic channel setting, it is possible to prevent the consumption of time and effort from the viewer's point of view. We can plan. In addition, during automatic channel setting, it is possible to accurately select a scrambled channel by determining whether a broadcast signal is scrambled through multiple steps.

Claims (5)

Sequentially scanning broadcast signals corresponding to each digital broadcast channel; Determining whether a broadcast signal corresponding to the broadcast channel is received; If the broadcast signal is received, determining whether at least one of a video signal and an audio signal is detected in the broadcast signal; And determining that the scrambled channel is not scrambled when the audio signal is detected, and storing information about the channel in a memory. The method of claim 1, The determining of whether the broadcast signal has been received may include determining whether the tuner for tuning the broadcast signal is operated. The method of claim 1, And determining whether the broadcast signal is divided into a video signal and an audio signal when the broadcast signal is detected. The method of claim 3, wherein And determining whether or not the video signal and the audio signal are separated by determining whether the demux is operating. The method of claim 4, wherein The step of determining whether the video signal and the audio signal are detected is the step of determining the decoded video signal and the audio signal; And determining that the video signal and the audio signal are simultaneously detected as a clear channel and storing the same in the memory.

Images