KR0153981B1 - Circuit for selecting output channel of image processor - Google Patents

Abstract

The present invention relates to an image processing apparatus (2) for inputting image signals of peripheral image processing apparatuses that are modulated and applied to three or four channels to the input terminal (21), which is connected to the input terminal (21), A first detector 22 outputting a first detection signal when a signal corresponding to the first signal is applied; A second detector 23 connected to the input terminal 21 and outputting a second detection signal when a signal corresponding to four channels is applied; An image processor 26 for processing and outputting an internal image signal; A first modulator 27 for modulating and outputting an image signal of the image processor 26 to a frequency corresponding to four channels; A second modulator 28 which modulates and outputs an image signal of the image processor 26 at a frequency corresponding to three channels; A control unit 24 for selectively outputting a switching signal and a display signal according to the first and second detection signals; A switch 25 switched according to a switching signal to selectively output the outputs of the first and second modulators 27 and 28; A display unit 30 for driving in accordance with a display signal to display a channel state of an image signal applied to the input terminal 21; The output terminal 28 which mixes and outputs the signal of the switch 25 with the signal of the input terminal 21 is provided.

That is, the present invention determines the channel of the video signal output from the devices (3,4) connected in series to the device (2) and automatically modulates the internal video signal to a channel not output from the device (3,4) It has the effect of improving the convenience by making the output.

Description

Modulation Channel Selection Circuit of Image Processing Unit

1 is a diagram showing a state in which an image processing apparatus having a modulation channel selection circuit according to the present invention is connected to a television.

2 is a block diagram of a modulation channel selection circuit of an image processing apparatus according to the present invention.

* Explanation of symbols for main parts of the drawings

21: input terminal 22, 23: detector

24 control unit 25 switch

26: image processor 27,29: modulator

30: display unit

The present invention relates to an image processing apparatus having a modulator capable of modulating and outputting an image signal of a predetermined channel to 3 or 4 channels of a television. More particularly, the present invention relates to an image processing apparatus having a modulator when the image processing apparatus is connected to a peripheral image processing apparatus. The present invention relates to a modulation channel selection circuit of an image processing apparatus that modulates and outputs an internal image signal as a frequency signal of three or four channels not used in a peripheral image processing apparatus.

In general, an image processing apparatus such as a VCR is provided with a modulator, and the modulator is usually driven in a television or VCR mode. That is, the modulator outputs the television broadcast signal received by the antenna inside the VCR through the external terminal in the television mode, and the television broadcast signal received by the antenna or the playback video signal of the VCR corresponds to the 3 or 4 channels of the television. It modulates to frequency (61.25MHz for 3 channels, 67.25MHz for 4 channels) and outputs it to the external terminal. Thus, the television connected to the VCR operates in a different mode accordingly in the operating mode of the VCR. For example, when the VCR operates in the television mode, the video signal of the external antenna is applied to the television from the VCR, thereby controlling the reception frequency of the television tuner so that the user can receive the desired television broadcast channel. However, when the VCR is driven in the VCR mode, a television signal is modulated with 3 or 4 channels, so only when the TV tuner's reception frequency is set to 3 or channel, it receives and processes the signal from the external terminal of the VCR. can do.

The reason why the VCR processes the internal video signal in 3 and 4 channels is as understood by those skilled in the art of the present invention. In the absence of a broadcast signal), the same applies to other video devices that can be connected to a television, such as a computer, an entertainment machine, a laser disc player, and the like.

Therefore, there is a case where the frequency of an image signal applied by each of the image processing apparatuses is the same as 3 or 4 channels in one television, and in this case, the signals of the image processing apparatuses are mixed or interfered with each other. In order to prevent such a case, the modulation channels of the image processing apparatuses must be set to be different from each other. However, the modulation channel of the modulator is changed manually, which causes inconvenience.

SUMMARY OF THE INVENTION The present invention has been made to solve this problem, and an object of the present invention is to select a modulation channel of an image processing apparatus to detect a modulation channel of a peripheral image processing apparatus and modulate the image signal as a channel that does not correspond to the detected channel. To provide a circuit.

In order to achieve the above object, the present invention provides an image processing apparatus for inputting image signals of peripheral image processing apparatuses that are modulated and applied to 3 or 4 channels to an input terminal, which is connected to an input terminal and corresponds to 3 channels. A first detector outputting a first detection signal when a signal is applied; A second detector connected to an input terminal and outputting a second detection signal when a signal corresponding to four channels is applied; An image processor which processes and outputs an internal image signal; A first modulator for modulating and outputting an image signal of a video processor to a frequency corresponding to four channels; A second modulator for modulating and outputting an image signal of a video processor to a frequency corresponding to three channels; A controller selectively outputting a switching signal and a display signal according to the first and second detection signals; A switch switched according to a switching signal to selectively output an output of the first and second modulators; A display unit which displays a channel state of an image signal applied to an input terminal by driving according to a display signal; An output terminal for mixing the signal of the switch with the signal of the input terminal for output.

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

FIG. 1 is a diagram showing an example in which the television 1, the video, and the processing devices 2, 3, 4 are connected.

As can be readily seen from the figure, the outputs of the image processing apparatuses 2, 3, 4 are each connected in series. In this case, when the image processing apparatuses 2, 3, and 4 modulate and output the internal signals into three (or four) channels, the signals displayed on the television (1) cannot be identified by mixing these signals with each other. It becomes In order to prevent the mixing between the modulation channels as described above, two of the image processing apparatuses 2, 3, and 4 are turned on, and the on-state imaging apparatus is configured to have internal video signals with different 3 and 4 channels. It should be configured to modulate the output. In this case, the user may select and view signals (of 3 and 4 channels) applied from the image processing apparatus in a power-on state.

On the other hand, in the conventional method, only two image processing apparatuses among the plurality of image processing apparatuses 2, 3, and 4 are powered on, and the image processing apparatuses need to set different modulation channels to each other. Cause.

In the present invention for solving this problem, the apparatus shown in FIG. 2 is constituted in the image processing apparatus 2 directly connected to the television.

As shown in FIG. 2, an output image signal of the image processing apparatus 3 is input to the input terminal 21 of the image processing apparatus 2. In this case, the image signal of the image processing apparatus 3 may be a signal modulated by 3 or 4 channels, or may be a signal in which signals modulated by 3 or 4 channels are mixed. Detectors 22 and 23 are connected to the input terminal 21, respectively, and the detector 22 filters only signals corresponding to three channels from an image signal applied from the input jar 21, and synchronizes the filtered signals. The signal is detected to output a first detection signal having a high or low level. In addition, the detector 23 filters only signals corresponding to four channels from the image signal applied from the input terminal 21, detects a synchronous signal from the filtered signal, and outputs a second detection signal having a high or low level.

The detection units 22 and 23 are connected to the control unit 24, respectively, and the control unit 24 is configured to output a switching signal and a display signal according to the first and second detection signals. That is, the controller 24 according to the present embodiment outputs a high level switching signal when only the first detection signal is applied. When only the second detection signal is applied, a low level switching signal is output. In addition, the controller 24 continuously outputs a low or high level switching signal that was previously output when neither of the first and second detection signals is applied, and also when the first and second detection signals are both applied previously. The low or high level switching signal is output, but the display signal is configured to be output in addition to the switching signal.

A switch 25 is connected to the control unit 24. The switch 25 is switched to the terminal a when a high level switching signal is applied, and is connected to the terminal b when a low level switching signal is applied. Switching. Modulators 27 and 29 are connected to the input terminals a and b of the switch 25, respectively, and internal video signals (video signals of a demodulated magnetic tape in the case of a VCR) to the modulators 27 and 29, respectively. The image processing unit 26 for processing and applying the modulators 27 and 28 to the modulators 27 and 28 is connected. The modulator 27 modulates an image signal of the image processor 26 as a video signal corresponding to four channels and applies the modulated signal to the terminal a of the switching 25. The video signal is modulated as a video signal corresponding to three channels and applied to the terminal b of the switching 25. Here, reference numeral 28 denotes an output terminal of the image processing apparatus 2, and the output terminal 28 and the input terminal 21 are connected to each other as shown.

The display signal of the control unit 24 is applied to the display unit 30, and the display unit 30 is configured to drive when the display signal is applied. The display unit 30 may be implemented as a light emitting diode or a liquid crystal display.

In the device 2 of the present invention having such a configuration, when only the video signals corresponding to the 3 channels from the devices 3 and 4 are applied, the detection signal is applied only to the detection unit 22 to the control unit 24. In this case, the controller 24 outputs a high level switching signal to switch the switch 25 to the terminal a so that the output of the image processor 26, that is, the signal corresponding to four channels in the modulator 27, is output. Outputs a modulated signal. Thus, the user sets the tuner of the television 1 to three or four channels so that the television 1 can output a four channel image signal of the image processing apparatus 2 or a three channel image signal of the image processing apparatus 3 or 4. Can be selectively displayed.

In addition, in the device 2 of the present invention, when only the video signals corresponding to the four channels from the devices 3 and 4 are applied, the detection signal is applied to the control unit 24 only from the detection unit 23. Accordingly, the controller 24 outputs a low level switching signal to cause the switch 25 to switch to the terminal b so that the signal of the image processor 26, that is, the signal corresponding to three channels in the modulator 29, is output. Outputs a modulated video signal. Thus, the user can control the tuner of the television 1 to cause the television 1 to selectively display the three channel image signal of the image processing apparatus 2 or the four channel image signal of the image processing apparatus 3 or 4. Can be.

However, in the device 2 of the present invention, when the image signals corresponding to the 3 and 4 channels from the devices 3 and 4 are not applied, the detection unit 22 and 23 is not applied to the control unit 24. Will not. In this case, the controller 24 applies the low or high level switching signal of the previous state, so that the switch 25 corresponds to 4 or 3 channels at the output of the image processor 26, that is, the modulator 27 or 29. To output a video signal modulated with a signal. Thus, the user can control the tuner of the television 1 to cause the television 1 to display the video signal of the four and three channels of the image processing apparatus 2.

In addition, in the apparatus 2 of the present invention, when the image signals corresponding to the 3 and 4 channels from the devices 3 and 4 are applied in a mixed state, the control unit 24 detects the detection unit 22 and 23. Signals are applied respectively. In this case, the control section 24 applies the low or high level switching signal of the previous state and outputs the display signal. Accordingly, the switch 25 outputs an image signal modulated by a signal of the image processor 26, that is, a signal corresponding to 4 or 3 channels by the modulator 27. As a result, the modulated signal of the image processor 26 is mixed with the video signal of the apparatus 3 or 4 so that the video signal of the corresponding channel cannot be displayed correctly on the television.

At this time, by the display unit 30 driven by the display signal, the user is currently outputting video signals of 3 and 4 channels by the devices 3 and 4, and the device 2 also outputs 3 or 4 channels of video signals. It can be easily seen that the output state. In this case, the user will have to stop driving the device 2, 3 or 4, which is considered the least necessary of the devices 2, 3 and 4.

As described above, the present invention determines the channel of the video signal output from the devices 3 and 4 connected in series with the device 2, and automatically modulates the internal video signal into a channel not output from the devices 3 and 4. It has the effect of improving the convenience by making the output.

Claims (1)

An image processing apparatus 2 for inputting image signals of peripheral image processing apparatuses modulated and applied to three or four channels to an input terminal 21, which is connected to the input terminal 21 and corresponds to the three channels. A first detector 22 outputting a first detection signal when a signal is applied; A second detector 23 connected to the input terminal 21 and outputting a second detection signal when a signal corresponding to the four channels is applied; An image processor 26 for processing and outputting an internal image signal; A first modulator 27 for modulating and outputting an image signal of the image processor 26 to a frequency corresponding to four channels; A second modulator 28 which modulates and outputs an image signal of the image processor 26 at a frequency corresponding to three channels; A controller 24 for selectively outputting a switching signal and a display signal according to the first and second detection signals; A switch 25 switched according to the switching signal to selectively output the outputs of the first and second modulators 27 and 28; A display unit 30 driving the display signal to display a channel state of an image signal applied to the input terminal 21; And an output terminal (28) for mixing and outputting the signal of the switch (25) with the signal of the input terminal (21).