KR20000044741A - Method for switching mode of hdtv - Google Patents

Abstract

PURPOSE: A method for switching a mode of an HDTV(High Definition Television) is provided to switch a video mode for detecting a synchronous signal. CONSTITUTION: A method for switching a mode of an HDTV comprises the steps of: determining whether the power is provided, or not; reading a stored mode and switching temporally a current mode to the stored mode if the power is provided; determining whether a synchronous signal is detected, or not; switching the current mode to the stored mode if the synchronous signal is detected; switching selectively a broadcasting signal and audio/video signals from an outer terminal until the broadcasting signal and the audio/video signals are searched from an outer terminal if the synchronous signal is not detected; determining whether the synchronous signal is detected in a searched mode, or not; and switching the searched corresponding mode if the synchronous signal is detected.

Description

Mode switching method of high definition TV

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to mode switching of high definition television (HDTV), and more particularly, to a mode switching method of high definition television capable of automatically switching to a video mode in which a synchronization signal is detected when the high definition television is powered on.

As is well known, high-definition televisions have increased the number of scanning lines and the number of pixels compared to conventional televisions, which has more than doubled the vertical and horizontal resolution and improved problems such as color bleeding. (compact disk) A new television system that delivers sound quality digital audio performance for crisp, vibrant images and clear sound.

In other words, high-definition televisions are TVs with higher resolution by increasing the number of scanning lines of 525 (in the case of NTSC) televisions to 1,125 in general televisions in order to apply the sense of realism and realism in movies to televisions. It's a widescreen type of longer movie.

Such high-definition television includes a mode memory function as in a normal television. The mode memory function means that when the viewer turns off the television in a predetermined mode, for example, VCR mode, the final mode data, i.e., VAL mode data (channel 3 or channel), is stored in a memory means in the television, for example, EEPROM. 4) When the TV is turned on again, it is a convenient function that reads the stored mode data, that is, the VRC mode data and automatically displays the screen corresponding to the mode to the viewer.

In addition, in the case of high-definition television, a tuner for watching high-definition broadcasting and general broadcasting in parallel, and an A / V terminal for watching high-definition video and general video in parallel, respectively, are provided to provide users with more various modes. It has advantages.

As described above, when the user turns off the power of the high-definition television and then turns on the power, the user switches to the mode at the time of turning off the power and displays the broadcast or the image when the power is turned off. have.

By the way, if a predetermined broadcast signal exists in a mode when the power of the high-definition television is turned on, for example, a video mode, the viewer can easily watch the broadcast, but if the broadcast signal does not exist in the mode at power-on, In addition, it was necessary to switch to the mode in which the broadcast signal exists by performing key operation again. That is, there is a problem that inconveniences occur in key operation.

Accordingly, the present invention has been made to solve the above problems, and when the power of the high-definition television is turned on, the high-definition television of the high-definition television which automatically switches to a mode in which a synchronous signal is detected by searching the stored mode and all the searchable modes when the power is turned off. The purpose is to provide a mode switching method.

In order to achieve the above object, the present invention provides a mode switching method of a high-definition television in which mode information when power is turned off, which receives a broadcast signal and an audio / video signal from an external terminal, is determined. A second step of reading the stored mode information and temporarily switching to the stored mode if the power is turned on, a third step of determining whether a synchronization signal is detected, and a third step As a result of the determination of the step, if the synchronization signal is detected, the fourth step of switching to the stored mode; if the synchronization signal is not detected, the entire mode of the broadcast signal and the audio / video signal from the external terminal is determined. A fifth search mode for performing a mode search operation for selectively temporarily switching broadcast signals and audio / video signals from external terminals until searching; And a sixth step of determining whether a synchronization signal is detected in the searched mode, and a seventh step of switching to the searched corresponding mode if the synchronization signal is detected as a result of the sixth determination. Provide a method.

1 is a schematic block diagram of a mode switching device of a high definition television for performing the method according to the present invention;

2 is a flowchart of a mode switching process of a high definition television according to a preferred embodiment of the present invention.

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

100: high-definition broadcast tuner 101: high-definition broadcast decoder

102: general broadcast tuner 103: general broadcast decoder

104: A / V switching unit 106: video signal processing unit

108: sync signal detection unit 110: key input unit

112: microcomputer 114: memory unit

The above and other objects and various advantages of the present invention will become more apparent from the preferred embodiments of the present invention described below with reference to the accompanying drawings by those skilled in the art.

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

1 is a schematic block diagram of a mode switching apparatus of a high definition television for performing a method according to the present invention, which includes a high definition broadcast tuner (HDTV tuner) 100, a high definition broadcast decoder 101, and a general broadcast tuner (SDTV tuner) ( 102, the general broadcast tuner 103, the A / V switching unit 104, the video signal processing unit 106, the synchronization signal detection unit 108, the key input unit 110, the microcomputer 112 and the memory unit 114 Include.

As shown, the high-definition broadcasting tuner 100 tunes an encoded high-definition broadcast signal received from a broadcasting station to a predetermined channel and provides the high-definition broadcasting decoder 101, and the high-definition broadcasting decoder 101 provides the tuned broadcast signal. The decoding is performed to the next stage A / V switching unit 104.

The general broadcast tuner 102 tunes an encoded general broadcast signal received from a broadcasting station to a predetermined channel and provides the same to the general broadcast decoder 103. The general broadcast decoder 103 decodes the tuned broadcast signal in such a way that Output to the A / V switching section 104.

The A / V switching unit 104 selectively switches the broadcast signals decoded from these high quality and general broadcast decoders 101 and 103 under the control of the microcomputer 112 described later. That is, a mode switching operation, for example, a mode switching operation for switching a high definition broadcast mode or a general broadcast mode, or performing a broadcast channel switching operation. In addition, the A / V switching unit 104 switches an external video signal, that is, a high quality video signal or a general video signal. That is, the A / V switching unit 104 is connected to an A / V terminal (not shown), and switches high quality and general video signals from a playback medium such as a video cassette recorder.

The video signal processor 106 extracts a video signal from high definition and general broadcast signals provided through an antenna or an external video signal input terminal, converts the video signal into a displayable signal, and outputs the video signal to a monitor (not shown).

The synchronization signal detector 108 detects a synchronization signal carried in the predetermined broadcast signal switched from the A / V switching unit 104 and provides the detected data to the microcomputer 112 described later.

Here, the synchronizing signal has the same meaning as a signal used for synchronizing between a general transmitter and a receiver. In a television video signal, the horizontal synchronizing signal and the vertical deciding field start are determined. It consists of a synchronization signal. The synchronization signals in the video signals are used for other functions of the video device besides synchronizing the scanning lines. For example, a television or the like is provided with a channel automatic tuning function, which automatically stores only a broadcast channel in a television among a plurality of receivable channels. In order to perform the channel auto-tuning function, it is necessary to determine whether the reception channel is a broadcast channel, and whether or not the broadcast channel is generally determined as the presence or absence of a synchronization signal. That is, when determining the presence or absence of a synchronization signal as in the channel automatic tuning function, since the broadcast signal is affected by noise in the transmission process, the synchronization signal is included when a predetermined number of synchronization signals are detected within a predetermined time. It is judged by the presence of a signal. For example, in the case of the NTSC system, it is determined that the signal includes the synchronization signal when 15 to 64 synchronization signals are detected within 2 msec.

On the other hand, the key input unit 110 generates a key signal according to the user's key input operation, that is, the pressed key. That is, the power key is formed on the key pad (not shown) of the key input unit 110. The power on / off setting signal of the high definition television according to the input operation of the power key is applied to the microcomputer 112 described later.

The memory unit 114 according to the present exemplary embodiment may be configured of, for example, EEPROM (Electrically Erasable and Programmable Read Only Memory), and predetermined data are selectively read out under the control of the microcomputer 112. That is, the memory unit 114 stores mode data and the like at the time of power-off of the high-definition television used in the present embodiment, and these data are read out by the microcomputer 112.

The microcomputer 112 according to the present invention can automatically switch the mode at power-on of the high-definition television by selectively controlling the above-described configurations.

The control operation of the microcomputer 112 will be described in detail with reference to the flowchart of FIG. 2.

2 is a flowchart of a mode switching method of a high-definition television according to the present invention, on the premise that mode data and the like at the time of power-off as described above are pre-stored in the memory unit 114.

First, in step S200, the microcomputer 112 determines whether the power is on. That is, it is determined whether the power-on key signal is applied from the key input unit 110.

As a result of the determination of step S200, if the power is turned on, that is, if the power-on key signal is applied, the microcomputer 112 proceeds to step S202 to read out the mode information previously stored in the memory unit 114 and performs the step ( Proceed to S204).

In step S204, the microcomputer 112 temporarily provides a switching control signal according to the read mode information to the A / V switching unit 104, and proceeds to step S206.

In operation S206, the microcomputer 112 determines whether a synchronization signal is detected in a predetermined broadcast or video signal according to the temporary switching operation of the A / V switching unit 104. In other words, the predetermined synchronization signal is detected from the above-described synchronization signal detector 108.

As a result of the determination in step S206, if a synchronization signal is detected, the microcomputer 112 proceeds to step S208 and the A / V switching unit 104 switches the broadcast or video signal to the storage mode stored in the memory unit 114. ).

On the other hand, if the synchronization signal is not detected as a result of the determination in step S206, the microcomputer 112 proceeds to step S210 to perform a mode search operation for selectively temporarily switching the broadcast signal and the A / V signal from the external terminal. The process proceeds to step S212. That is, the A / V switching unit 104 is controlled to temporarily switch the received broadcast signal and A / V signals.

In step S212, the microcomputer 112 determines whether a synchronization signal is detected in the currently searched mode. That is, it is determined whether predetermined synchronization signal data is input from the synchronization signal detector 108.

As a result of the determination in step S212, when the synchronization signal is detected, the microcomputer 112 controls the A / V switching unit 104 to switch to the current mode to the searched mode in step S214. Therefore, a predetermined video signal is output to the monitor not shown by the above-described signal processing operation of the video signal processing unit 106.

However, if the synchronization signal is not detected as a result of the determination in step S212, the microcomputer 112 proceeds to step S216 to determine whether the entire mode of the broadcast signal and the A / V signal from the external terminal has been searched.

As a result of the determination of step S216, if the entire mode has not been searched, the microcomputer 112 proceeds to step S210 to perform the mode search process again.

As a result of the determination in step S216, when the entire mode has been retrieved, the microcomputer 112 proceeds to step S218 in which the predetermined storage mode stored in the memory unit 114, that is, the initial storage mode that was stored when the power was turned off. The switching control signal for switching to the output to the A / V switching unit 104.

At this time, the video signal switched by the A / V switching unit 104 is not image processed on the monitor. That is, as described above, since no synchronization signal is detected in any of the modes searched in the full mode search process, the initial mode at the time of power-off is set.

As mentioned above, although the high-definition television which automatically switches the mode at the time of power-on according to the presence or absence of a synchronous signal was demonstrated, it is not limited to this. Those skilled in the art will be able to implement the method with other alternatives and modifications, such as a general television set, which will be readily apparent to one of ordinary skill in the art.

As described above, the present invention has the effect of eliminating user's inconvenience in key operation by automatically switching the current mode to the mode in which the synchronization signal exists when the power of the high-definition television is turned on.

Claims (1)

In the mode switching method of the high-definition television which stores the mode information when the power is turned off, which receives a broadcast signal and an audio / video signal from an external terminal, A first step of determining whether the power is on; A second step of reading the stored mode information and temporarily switching to the stored mode if the power is turned on as a result of the determination of the first step; Determining whether a synchronization signal is detected; A fourth step of switching to the stored mode if a synchronization signal is detected as a result of the determination of the third step; If the synchronization signal is not detected as a result of the third step, the broadcast signal and the audio / video signal from the external terminal may be selectively selected until the entire mode of the broadcast signal and the audio / video signal from the external terminal is searched. A fifth step of performing a temporarily switching mode search operation; A sixth step of determining whether a synchronization signal is detected in the searched mode; And a seventh step of switching to the searched corresponding mode if a synchronization signal is detected as a result of the sixth step.