KR100821761B1 - Display device and method for changing the channel thereof - Google Patents

Abstract

An object of the present invention is to provide a video display device that facilitates channel switching to a digital channel equivalent to an analog channel currently viewed by a user, and a channel switching method of the video display device.

In order to achieve the above object, the present invention comprises: a broadcast signal receiving step of receiving a broadcast signal including channel information; Extracting channel information from the received broadcast signal; A channel type determination step of determining a type of a current channel from the extracted channel information; An equivalent channel search step of searching for an equivalent digital channel if the current channel is an analog channel; An equal channel presence determination step of determining whether the equivalent digital channel exists; And a channel switching step of switching to the equivalent digital channel if the equivalent digital channel exists.

Description

Channel display method of image display device and image display device {Display device and method for changing the channel approximately}

1 is a flowchart illustrating a conventional channel switching method.

2 is a flowchart illustrating a channel switching method according to the present invention;

3 is a block diagram showing each part of the image display apparatus according to the present invention;

4 is a diagram showing a channel symbol.

Description of the main parts of the drawings

ST1: receiving broadcast signal ST2: extracting channel information

ST3: Channel Type Determination Step ST4: Equal Channel Search Step

ST5: Determination of Equal Channel Existence ST6: Channel Switching Step

110: receiver

120: signal processing unit 130: output unit

140: control unit 150: storage unit

The present invention relates to an image display device and a channel switching method of the image display device. A video signal that can be received by a current video display device (eg, a television) is largely divided into an analog signal and a digital signal. Each channel may be divided into an analog channel and a digital channel according to the type of the received signal. .

At present, the number of video channels transmitted by broadcasting stations has reached about 100. Especially at the present time when the signal of video display equipment is changing from analog to digital, there are analog channels and digital channels that transmit the same program. There have often been cases.

In general, the quality of the image received through the digital channel is better than the image received through the analog channel. In a conventional video display device, the user does not know that there is an equivalent digital channel while watching the analog channel, or even if he knows it, There was a problem that the channel must be found and channel switched (see FIG. 1).

SUMMARY OF THE INVENTION An object of the present invention is to provide a video display device and a channel switching method of the video display device that facilitates channel switching to a digital channel equivalent to an analog channel currently viewed by a user. .

In order to achieve the above object, the present invention comprises: a broadcast signal receiving step of receiving a broadcast signal including channel information; Extracting channel information from the received broadcast signal; A channel type determination step of determining a type of a current channel from the extracted channel information; An equivalent channel searching step of searching for an equivalent digital channel if the current channel is an analog channel; An equal channel presence determination step of determining whether the equivalent digital channel exists; And a channel switching step of switching to the equivalent digital channel if the equivalent digital channel exists.

The extracting of the channel information may include separating a data signal from the received broadcast signal, and reading channel information from the separated data signal, and storing the read channel information. It is more preferable to further include.

The searching of the equivalent channel may include comparing the information of the current channel with information of another channel to determine whether the channels are equivalent, and storing the result of the determination.

The channel information is at least one of a broadcasting station name, a channel number, a program number, a program title, a program start time, a program end time, caption information, a channel symbol, and an electronic program guide. It is preferably included in at least one of the video signal section and the blanking section.

In addition, to achieve the above object, the present invention comprises: a receiving unit for receiving a broadcast signal including channel information; A signal processor extracting channel information from the received broadcast signal; Determining the type of the current channel from the extracted channel information, if the current channel is an analog channel to search for the equivalent digital channel to determine the presence, if there is an equivalent digital channel control to switch to the equivalent digital channel It provides a video display device comprising a.

The signal processor preferably includes a demultiplexer for separating a data signal from the received broadcast signal.

The controller may include a central processing unit that reads channel information from the separated data signal, and compares information of a current channel with information of another channel to determine whether the channels are equal.

The controller may further include a control memory unit for storing the read channel information and the search result of the equivalent digital channel.

Hereinafter, a channel switching method of an image display device according to the present invention will be described in detail with reference to FIGS. 2 to 4. In the channel switching method of the video display device according to the present invention, the broadcast signal receiving step (ST1), the channel information extraction step (ST2), the channel type determination step (ST3), the equal channel search step (ST4), the presence of the equivalent channel determination A step ST5 and a channel switching step ST6 are described below. Each of these steps will be described in detail below.

The broadcast signal receiving step ST1 is a step of receiving a broadcast signal including channel information. The broadcast signal includes a video signal, an audio signal, and a data signal. The channel information may be included in at least one of a transport stream of a digital broadcast signal, a video signal section, and a blanking section of the analog broadcast signal.

In the case of a video display device having more than one tuner, there is another tuner other than the tuner that is receiving the video and audio signals of the current channel, that is, the channel the user is watching. It is performed by at least one of a tuner and another tuner, and all tuners may be utilized.

The channel information extracting step (ST2) is a step of extracting channel information from the received broadcast signal, including separating the data signal from the broadcast signal and reading the channel information from the separated data signal. Preferably, the method may further include storing the read channel information. Of course, the read channel information includes information of the current channel.

The data signal may include caption (caption), electronic program guide (EPG), etc., as well as channel information such as channel type, frequency band, and the like. Herein, the electronic program guide is not limited to a specific standard, but corresponds to information containing a program information (channel, title, start time, end time, etc.).

In the above, a method of extracting channel information is most easily extracted, that is, a method of extracting channel information using a data signal included in a broadcast signal. However, extracting channel information from a video signal of a broadcast signal is also described. It is possible. In other words, a channel symbol such as a logo of a broadcasting station that transmits each channel is often displayed in an image obtained by processing a video signal, and thus may be used.

The channel symbol CS refers to a symbol representing a specific channel of a specific broadcasting station illustrated as “MBC” on the screen S of FIG. 4, and when more than one channel is operated by one broadcasting station (for example, culture In the case of broadcasting, the channel is usually displayed with different channel symbols "MBC" and "MBC DRAMA" as well as regular airwave channels as well as drama channels. It can be recognized as.

In particular, when a broadcasting station transmits a high-resolution digital program, "HD" may be written together with the channel symbol at the upper right of the screen, which is a clue that there is a digital channel. After determining whether there is a symbol such as "HD" in the image, a channel type determination step ST3 to be described later may be performed accordingly.

In checking whether there is a channel symbol in the image of the analog channel, it is preferable to convert the analog image signal into a digital image signal, which is performed by the A / D converter in the analog image decoder 122 shown in FIG. . From the digital video signal thus converted, pictures constituting the image are selected at predetermined time intervals (for example, three pictures are selected at intervals of 1 second), the contours of the selected pictures are extracted, and the common contours are extracted. If you detect this, you can check the channel symbol. If there is no common contour, it is determined that there is no channel symbol.

In checking the channel symbol as described above, if image processing techniques such as character recognition are used for the outline as necessary, or if the channel symbol is checked only for a specific area (typically four corners of the screen), Verification can be done accurately and / or quickly.

The channel type determination step ST3 is a step of determining the current channel type from the extracted channel information. The type of channel means whether a channel for receiving a digital broadcast signal or a channel for receiving an analog broadcast signal. Subsequent steps are performed when the current channel is an analog channel. The channel switching method ends (the end of the channel switching method means that the current channel is maintained).

This step may be performed by using the channel information obtained in the channel information extraction step ST2. In addition, each part of the image display apparatus (particularly, the receiver 110, the signal processor 120, and the controller 140) may be performed. ) Can also be performed through signals sent and received.

The equal channel search step ST4 is performed when the current channel is an analog channel and searches for a digital channel equivalent to the current analog channel. This step can include storing the results of the search. For reference, 'equivalent digital channel' means a digital channel through which a program such as a program received through an analog channel is received.

When the channel information is read from the data signal, since the existence of the digital channel equivalent to the current analog channel, the number of the channel, etc. can be easily found therefrom, this step is performed using the same. More specifically, it is determined whether the channels are equal by comparing the read current channel information with information of other channels.

In determining the equality of the two channels to be compared, it is checked whether at least one of a broadcasting station name, a channel number, a program number, a program title, a program start time, a program end time, caption information, and a channel symbol among each channel information matches. It is desirable to compare all available information to improve the accuracy of the judgment.

When information on the current channel is obtained from a video signal, that is, when the current channel is recognized as a specific channel by the channel symbol, the channel symbol is extracted for other channels, and this step is determined by determining whether it is the same as the channel symbol of the current channel. Is performed.

An equal channel presence determination step (ST5) is a step of determining whether the equivalent digital channel exists, and if it is determined that an equivalent digital channel exists, a channel switching step of converting a viewing channel of the user into the equivalent digital channel is performed. Otherwise, the channel switching method according to the present invention is terminated.

Hereinafter, an image display device according to the present invention will be described in detail with reference to FIG. 3. The image display device according to the present invention includes a receiver 110, a signal processor 120, an outputter 130, and a controller 140, and may further include a storage 150 as necessary.

The receiver 110 includes an external signal input unit 111, an analog tuner 112, an analog demodulator 113, a digital tuner 114, and a digital demodulator 115. The external signal input unit 111 receives an external signal received from an external device such as a camcorder and provides the signal to the signal switching unit 121.

The analog tuner 112 and the digital tuner 114 tune and receive at least one channel according to the control signal of the central processing unit 142, and receive the received broadcast signal, respectively, the analog demodulator 113 and the digital demodulator. Forward to 115. The analog demodulator 113 and the digital demodulator 115 demodulate the received signal. The analog demodulator 113 may include an NTSC receiver, and the digital demodulator 115 may include a VSB receiver. The signal output through the VSB receiver has a form of a transport stream (TS).

The signal processor 120 may include a signal switcher 121, an analog video decoder 122, a demultiplexer 123, a digital video decoder 124, a digital audio decoder 125, a timing signal processor 126, and an image signal processor. 127, and an image memory unit 128.

The signal switching unit 121 may include a switching function for selecting at least one channel among channels provided from the external signal input unit 111 and the analog demodulation unit 113, and a video / audio / data signal of the signal. Perform demultiplexing function to separate.

The analog video signal separated by the signal converting unit 121 is converted to the digital video signal by the analog video decoder 122 and then deinterlaced and then transferred to the video signal processing unit 127. The analog voice signal separated by the signal switching unit 121 is directly provided to the voice signal output unit 133, and the data signal separated by the signal switching unit 121 is transferred to the central processing unit 142. The separation of the video signal, the audio signal, and the data signal may be performed by a demultiplexer (not shown) included in the signal switching unit.

The demultiplexer 123 shown in FIG. 3 separates the digital video signal, the digital audio signal, the timing signal, and the data signal included in the transport stream, and respectively decodes the digital video decoder 124, the digital audio decoder 125, and the timing signal. Transfer to the processing unit 126 and the central processing unit 142. An MPEG decoder may be used as the digital video decoder 124, and an AC-3 decoder may be used as the digital audio decoder 125. The timing signal processor 126 recovers the program clock and synchronizes the digital video signal with the audio signal. The digital video signal via the digital video decoder 124 is transmitted to the video signal processor 127, and the digital audio signal via the digital audio decoder 125 is transmitted to the audio signal output unit 133.

The above-described channel information is included in the data signal and / or the video signal included in the broadcast signal. As described above, the channel information is extracted by separating the video signal and the data signal.

The video signal processor 127 processes (eg, scales) the video signals provided from the analog video decoder 122 and the digital video decoder 124 and provides them to the video signal output unit 131. In addition, according to the control signal received from the central processing unit 142, it also performs a function of multiplexing the video signal received through the tuner (112, 114) and the like to display the caption, OSD, PIP, and the like. The image memory unit 128 provides a memory area required for decoding and image signal processing of the image signal processor 127.

The output unit 130 includes an image signal output unit 131, a display module 132, an audio signal output unit 133, and a speaker 134.

The image signal output unit 131 (which may include an LVDS receiver) may process the image signal output from the image signal processing unit 127 into a form that can be output through the display module 132, and The voice signal output unit 133 processes the voice signal output from the digital voice decoder 125 and the signal switching unit 121 in a form that can be output through the speaker 134. The voice signal output unit 133 includes a D / A converter.

The controller 140 includes an interface unit 141, a central processing unit 142, and a control memory unit 143. The interface unit 141 may be, for example, a local key button attached to a remote controller or an image display device. The interface unit 141 receives various commands and information from a user, converts the control signal into a control signal, and transfers the control signal to the central processing unit 142. .

The central processing unit 142 controls the tuners 112 and 114, the signal switching unit 121, the demultiplexer 123, and the image signal processing unit 127, and controls other components of the image display device as necessary. It can be designed to do so.

In particular, in accordance with the present invention, the controller 140 determines the type of the current channel from the extracted channel information, and, if the current channel is an analog channel, searches for the equivalent digital channel to determine whether the channel exists. If there is a digital channel equivalent to an analog channel, it performs its main function in the sequence of processes to switch to that equivalent digital channel.

More specifically, the central processing unit 142 of the control unit 140 reads out channel information from the separated data signal, and the control memory unit 143 of the control unit 140 stores the read channel information and the equivalent digital channel. Search results may be stored. In addition, the control memory unit 143 stores information input by a user and / or data generated and managed by the central processing unit 143.

The storage unit 150 includes a storage control unit 151 and a storage medium 152. The storage controller 151 may store the image signal output from the image signal processor 127 in the storage medium 152 according to the control signal of the central processor 142. Although not shown in FIG. 3, the digital voice signal converted from the analog voice signal output from the signal switching unit 121 and the digital voice signal output from the digital voice decoder 125 may also be stored in the storage medium 152. . In addition, the storage controller may read out the image / audio signal stored in the storage medium 152 and provide the image / audio signal to the image signal processor 127 and the audio signal output unit 133.

According to the present invention, there is provided a channel switching method of a video display device that confirms the existence of a digital channel equivalent to an analog channel that a user is currently watching, and enables a quick switching to the digital channel whose existence has been confirmed.

Although the present invention has been described with reference to the embodiments shown in the drawings, this is merely exemplary, and those skilled in the art will understand that various modifications and equivalent other embodiments are possible. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

Claims (9)

A broadcast signal receiving step of receiving a broadcast signal including channel information; Extracting channel information from the received broadcast signal and separating a data signal from the channel information; A channel type determination step of determining a type of a current channel from the separated data signal; If the current channel is an analog channel, determining whether a digital channel equal to the analog channel exists using the channel information; And a channel switching step of switching to the equivalent digital channel if the equivalent digital channel exists. The method of claim 1, The channel information extracting step includes separating a data signal from the received broadcast signal, and reading channel information from the separated data signal. The method of claim 2, The channel information extracting step further comprises the step of storing the read channel information. The method of claim 1, The searching of the equivalent channel may include comparing the current channel information with information of another channel to determine whether the channels are equivalent, and storing the result of the determination. . The method of claim 1, And the data signal is at least one of a broadcasting station name, a channel number, a program number, a program title, a program start time, a program end time, caption information, a channel symbol, and an electronic program guide. The method of claim 1, And the channel information is included in at least one of a transport stream of a digital broadcast signal, a video signal section, and a blanking section of the analog broadcast signal. A receiver configured to receive a broadcast signal including channel information; A signal processor extracting channel information from the received broadcast signal to separate a data signal; A controller for determining a type of a current channel from the data signal, searching for an equivalent digital channel if the current channel is an analog channel, and determining whether there is an existing channel, and converting to an equivalent digital channel if an equivalent digital channel exists. Image display device comprising. The method of claim 7, wherein The signal processor includes a demultiplexer for separating a data signal from the received broadcast signal, And the control unit includes a central processing unit which reads channel information from the separated data signal, and compares information of a current channel with information of another channel to determine whether the channels are equal. The method of claim 8, And the control unit further comprises a control memory unit for storing the read channel information and a search result of an equivalent digital channel.

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