Simultaneous display device for television video and personal computer video

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to a video signal processing technique for television, and more specifically, a personal computer image and a television image are divided into two and displayed on a television receiver, and the personal computer image and the television image are displayed on the television screen. It relates to a simultaneous display device for television and personal computer images that can be displayed at the same time.

【0002】

[Conventional technology]

In the circuit of a conventional television system capable of displaying two screens, as shown in FIG. 5, the first control signal CS and the second control signal dw for generating two screens are output according to the viewer's selection. The microcomputer 106 and the first control signal CS output the main video signal Vim that has passed through the main tuner and the intermediate frequency IF processing unit (not shown), and the sub tuner and the sub video signal Vis that has passed through the intermediate frequency and the external input. In the signal Vex, the audio / video switch 101 that outputs any one signal and the main video signal Vim that is output from the audio / video switch 101 are 3.58 MHz. The first comb-shaped filter 102, which is separated into a main brightness signal Ym and a main color signal Cm by using the subcarrier frequency fsc of the above and applied to the audio / video switch 101, and the sub video output from the audio / video switch 101. The second comb-shaped filter 103 that separates the signal Vis or the external input signal Vex signal into the sub-brightness signal Ys and the sub-color signal Cs and outputs them, and the main brightness signal Ym and the main color that are output from the audio / video switch 101. The two-screen control unit 104 that receives the signal Cm, the sub-brightness signal Ys and the sub-color signal Cs output from the second comb-shaped filter 103, and outputs the two-screen brightness signal Ydw and the two-screen color signal Cdw, and the microcomputer 106. The main brightness signal Ym and the main color signal Cm are input from the audio / video switch 101 by the second control signal dw, or the two screen brightness signal Ydw and the two screen color signal Cdw output from the two screen control unit 104 are input. A two-screen switch 105 that receives and outputs a brightness signal Y and a color signal C, and a brightness signal Y and a color signal C that are output from the two-screen switch 105 are converted into a color signal (RGB) by an internal matrix, amplified, and output. It is provided with a video chroma signal processing unit 107, and an RGB amplifier 108 that converts the amplified RGB color signal into a size required to drive the brown tube 109 and applies it to each cathode of the brown tube 109. Was composed of.

【0003】

At this time, the external input signal Vex is a signal input to an external input terminal (not shown) of the television and means a video image signal or the like. Hereinafter, the operation of the conventional television system circuit capable of displaying two screens configured in this way will be described. First, the main video signal Vim that has passed through the main screen tuner and the intermediate frequency processing unit (not shown), the sub video signal Vis that has passed through the sub screen tuner and the intermediate frequency processing unit, and the external input signal Vex are audio / video switches. When input to 101, the audio / video switch 101 outputs the main video signal Vim to the first comb-shaped filter 102 via the first output terminal Vout1.

【0004】

Next, the viewer decides whether to watch the video by the sub video signal or the video by the external input signal Vex and adjusts the microcomputer, and as a result, the logic of the first control signal CS changes. Depending on the state, the sub video signal Vis or the external input signal Vex is output to the second comb-shaped filter 103 via the second output terminal Vout2.

【0005】

Next, the first comb-shaped filter 102 separates the main video signal Vim into a main luminance signal Ym and a main color signal Cm using a subcarrier frequency fsc of 3.58 MHz, and the separated principal luminance signal Ym and the main luminance signal Ym. The color signal Cm is input to the dual screen control unit 104 and the dual screen switch 105 via the audio / video 101. Further, the second comb-shaped filter 103 separates the sub-video signal Vis or the external input signal Vex output from the second output terminal Vout2 into the sub-luminance signal Ys and the sub-color signal Cs to the two-screen control unit 104. Output.

【0006】

The two-screen control unit 104 converts each input signal Ym, Cm, Ys, Cs into a digital signal, reads and writes it to a memory, and converts it into an analog signal again. At this time, the write timing of each memory The two-screen brightness signal Ydw and the two-screen color signal Cdw are generated with different lead timings and output to the two-screen switch 105 to perform a double window or PIP (Picture in picture) function. The frequency band used is about 2MHz.

【0007】

Next, when the viewer decides whether to watch one screen or two screens and adjusts the microcomputer 106, the logical state of the second control signal dw of the microcomputer 106 changes, and the said Depending on the logical state of the changed control signal, the two-screen switch 105 selects one of the signals Ym, Cm or each signal Ydw, Cdw and outputs the signal to the video chroma signal processing unit 107. The output signals Y and C are converted into color signals RGB by the internal matrix in the video chroma signal processing unit 107, amplified by the RGB amplifier 108 to a size required for driving the brown tube 109, and then the output signals Y and C are described. Since it is applied to each RGB cathode of the brown tube 109, one image is displayed on the screen by the main video signal, two screens are displayed by the main video signal and the sub video signal, or the main video signal and Two screens are displayed by the external input signal.

【0008】

In this way, the viewer can operate the microprocessor 106 to view the video processed on one screen or the video processed on two screens. Then, when the viewer attempts to view the video processed by the personal computer by dividing it into two screens using such a conventional device, the viewer uses the output end output by the video signal of the personal computer as the external input end. When connected, the video signal processed from the personal computer is input to the audio / video switch 101 via the external input terminal. That is, the external input signal Vex of the audio / video switch 101 becomes a personal computer video signal.

【0009】

After that, when the viewer adjusts the microcomputer 106, the two-screen switch 105 passes through the two-screen luminance signal Ydw and the two-screen color signal Cdw output from the two-screen control unit 104 by the second control signal dw. Two screens are displayed on the screen by the main video signal and the personal computer video signal, and the television video and the personal computer video can be viewed at the same time.

【0010】

On the other hand, the video frequency band used in television is about 2 to 3 MHz, and the high-resolution video frequency band used in personal computers is about 20 MHz in VGA mode. That is, the horizontal frequency 2H of the personal computer image is about 31.5 kHz, which is twice the horizontal frequency H of the television, and when the number of horizontal dots is 640, the frequency band is 31.5 × 1000 × 640, which is about 20 MHz.

【0011】

In this way, in order to display high-resolution computer images on the screen normally, the hardware must process the frequency band of 20MHz.

【0012】

[Problems to be Solved by the Invention]

However, in such a conventional television circuit capable of displaying two screens, when a personal computer video signal is input to the audio / video switch 101, the personal computer video signal passes through the two screen control unit 104. Since the two-screen control unit 104 uses a frequency band of about 2 MHz, the resolution of a personal computer image that requires a frequency band of 20 MHz is greatly reduced.

【0013】

Therefore, an object of the present invention is to provide a television image and a computer image simultaneous display device capable of simultaneously displaying a television image and a personal computer image having a resolution higher than that of the television image by using a separate switching means. It is a thing. Another object of the present invention is to separately process a personal computer video signal without passing through a two-screen control unit in a narrow frequency band to simultaneously divide a high-resolution personal computer video and a television video into two screens. It is intended to provide a simultaneous display device for television images and personal computer images that can be viewed by the user.

【0014】

[Means for solving problems]

In order to achieve such an object of the present invention, the simultaneous display device of the television image and the personal computer image according to the present invention is a two-screen display device that displays a two-screen image, and the decoded main image signal and sub-image. A two-screen control unit that receives a signal and outputs a two-screen processed signal, and a computer signal processing unit that decodes the color signal (RGB) of a computer and outputs a synchronization signal for two-screen display from the synchronization signal of the computer. The switch control unit that outputs a selection signal for selecting the main image or the sub image in the two-screen image output from the two-screen control unit, and the switching signal of the switch control unit and the switch signal of the microcomputer are used for input. A switch unit that selects and outputs one of the two synchronization signals to be input, and selects and outputs one of the computer video signal, main screen video signal, and two-screen video signal to be input, and the switch. It is configured to include a first matrix unit that decodes the video signal output from the unit and outputs a color signal.

【0015】

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the first embodiment of the television image and personal computer image simultaneous display device according to the present invention, as shown in FIG. 1, the audio / video switch 101, the first comb-shaped filter 102, and the second comb-shaped filter 103 are used. , RGB amplifier 108 and CRT 109 are provided as before.

【0016】

Then, the main screen decoder 210 receives the main luminance signal Ym and the main color signal Cm from the audio / video switch 101 and separates the main color decoding signals (R-Ym = Um) (B-Ym = Vm). It is connected to output and output the main horizontal synchronization signal Hm and the main vertical synchronization signal Vm. Further, the sub-screen decoder 220 receives the sub-luminance signal Ys and the sub-color signal Cs from the second comb-shaped filter 103 and outputs the sub-color decoding signal (R-Ys = Us) (B-Ys = Vs). It is connected to the.

【0017】

Further, the two-screen brightness signal Ydw and the two-screen color decoding for the two-screen control unit 230 to receive the decoded signals Um, Vm, Us, Vs and the luminance signals Ym, Ys and display them on the two screens. It is connected so as to output the signals Udw and Vdw and output the two-screen selection signal YSdw for switching. Further, the microcomputer 240 has a first control signal CS, a second control signal A, and a first switch signal I whose logical state is changed according to the viewer's selection.²C1 and 2nd switch signal I²C2 is output respectively, the switch control unit 250 receives the two-screen selection signal YSdw output from the two-screen control unit 230, and outputs the third switching control signal YS'by the output second control signal A of the microprocessor 240. It is connected like.

【0018】

Then, the personal computer signal processing unit 260 generates a synchronization signal at the time of two-screen display by the personal computer synchronization signals Hp and Vp input from the personal computer, decodes the personal computer color signals Rp, Gp and Bp, and decodes the personal computer decoding signals Yp, It is connected to output Up and Vp. Further, the first switch signal I output by the switch unit 270 from the microcomputer 240²C1, 2nd switch signal I²Among the main synchronization signals Hm and Vm output from the main screen decoder 210 and the computer synchronization signals Hp and V output from the computer signal processing unit 260 by the third switch signal YS'output from C2 and the switch control unit 250. One of the synchronization signals is selected and output, and one of the main color decoding signals Um, Vm, the two-screen color decoding signals Udw, Vdw, and the personal computer decoding signals Yp, Up, Vp is decoded. Is connected to select and output. Further, a deflection unit 280 and a first matrix unit 290 are provided, and the decoding signal that has passed through the switch unit 270 is converted into a color signal (RGB) and output to the RGB amplifier 108.

【0019】

Further, in the personal computer signal processing unit 260, the second matrix unit 261 that decodes the color signals Rp, Gp, Bp and outputs the personal computer decoding signals Yp, Up, Vp, and the input synchronization signals Hp, The synchronization signal detector 262 that matches the polarity of Vp with the polarity of the main screen synchronization signals Hm and Vm (the polarity of the synchronization signal changed by selecting the graphics mode and text mode of the computer matches the polarity of the synchronization signal for the main screen. Synchronized signal detection unit), receives the personal computer synchronization signals Hp and Vp output from the synchronization signal detection unit 262, and outputs the combined synchronization signal Hc used as the synchronization signal when displaying two screens to the audio / video switch 101. It is equipped with a synchronization signal conversion unit 263 that generates a two-screen synchronization signal.

【0020】

Then, in the switch unit 270, the second switch control signal I of the microcomputer 240²Select from the first switch SW1 that selects the main color decoding signals Um, Vm or the personal computer decoding signals Yp, Up, Vp by C2, and the first switch SW1 by the third switch signal YS'of the switch control unit 250. The second switch SW2 for selecting the signal or the two-screen color decoding signals Udw and Vdw, and the first switch signal I of the microcomputer 240.²C1 includes a third switch SW3 that outputs the main synchronization signals Hm and Vm or the personal computer synchronization signals Hp and Vp to the deflection unit 280.

【0021】

Further, in the switch control unit 250, as shown in FIG. 2, when the two-screen selection signal YSdw is input, the signal (/) is transmitted from the inverting terminal (/ Q1) by the time constant determined by the resistor R1 and the capacitor C1. It is provided with a multi-vibrator 251 that outputs Q1) and a selection signal control unit 252 that inverts the output signal (/ Q) of the multi-vibrator 251 by the control signal A of the microcomputer 240 and outputs (the micro computer). The selection signal control unit 252 that passes or blocks the two-screen selection signal YSdw of the two-screen control unit 230 by the control signal A of 240) The selection signal control unit 252 is the output signal (/ Q1) of the multi-vibrator 251. ), The second switching transistor Q2 controlled by the control signal A of the microcomputer 240, and the first and second switching transistors Q1 and Q2 that operate by turning on / off. It is equipped with a 3-switching transistor Q3. At this time, R2, R3, and R4 of reference numerals in the figure each indicate a current limiting resistor, and D1 indicates a diode.

【0022】

Hereinafter, the operation of the simultaneous display device for the television image and the personal computer image according to the present invention configured as described above will be described. Operated by the main video signal Vim input via the main screen tuner and the intermediate frequency processing unit (not shown), the sub video signal Vis input via the sub screen tuner and the intermediate frequency processing unit, and the external input signal Vex. The operation of the audio / video switch 101, the first comb filter 102, and the second comb filter 103 is the same as before.

【0023】

First, the main screen decoder 210 receives the main brightness signal Ym and the main color signal Cm from the audio / video switch 101 and separates the main color decoding signals (R-Ym = Um) (B-Ym = Vm). At the same time as the output, the main horizontal synchronization signal Hm and the main vertical synchronization signal Vm are output, and the main color decoding signals Um and Vm are input to the terminal P2 of the first switch SW1 of the switch unit 270 to input the main synchronization signal Hm. , Vm is input to the terminal P6 of the third switch SW3 of the switch unit 270.

【0024】

Next, the sub-screen decoder 220 receives the sub-luminance signal Ys and the sub-color signal Cs from the second comb-shaped filter 103, and outputs the sub-color decoding signal (R-Ys = Us) (B-Ys = Vs). Next, the two-screen control unit 230, which receives the inputs of the main brightness signal Ym and the main color decoding signals Um, Vm, the sub-brightness signals Ys, and the sub-color decoding signals Us, Vs, converts the input signals into digital signals, respectively. A two-screen brightness signal Ydw and a two-screen color decoding signal that are converted, read and written to the internal memory, converted back to an analog signal, and processed on two screens with different memory write timings and read timings for each signal. Udw and Vdw are output to the terminal P4 of the second switch SW2 of the switch unit 270, and the two-screen selection control signal YSdw is output to the switch control unit 250. The two-screen selection signal YSdw is output high during the output period of the two-screen video signals Ydw, Udw, and Vdw, and as shown in FIG. 3, horizontal blanking excluding the two-screen video signal section ( During the H BLS) signal output period, it is output low and serves as a two-screen selection criterion.

【0025】

Next, the personal computer color signals Rp, Gp, Bp input to the personal computer signal processing unit 260 via the personal computer video output terminal are decoded into the personal computer decoding signals Yp, Up, Vp by the second matrix unit 261, and the first switch is described. Input to terminal P1 of SW1. After that, the polarities of the personal computer synchronization signals Hp and Vp input to the personal computer signal processing 260 differ depending on the graphic mode of the personal computer, and the synchronization signal detection unit 262 inputs the main synchronization signal Hm, to the terminal P6 of the third switch SW3. The personal computer synchronization signals Hp and Vp are output while maintaining a constant polarity so that they have the same polarity as Vm. At this time, the frequency of the personal computer horizontal synchronization signal Hp is about 31.5 kHz in the case of high-resolution graphics.

【0026】

The personal computer synchronization signals Hp and Vp output from the synchronization signal detection unit 262 are input to the synchronization signal conversion unit 263, converted into a composite synchronization signal Hc and output, and the composite synchronization signal Hc is the audio / video switch 101. It is input to and is used as a synchronization signal when the television image and the personal computer image are divided into two screens and displayed.

【0027】

After that, when the viewer operates the microprocessor 106, the second control signal A and the first and second switch signals I output from the microcomputer 106²C1, I²The logical state of C2 is changed. That is, the switch control unit 250 outputs the third switch signal YS with different logical states depending on the logical states of the control signal A and the two-screen selection signal YSdw, and the third switch signal YS outputs the third switch signal YS . 2 The connection status of switch SW2 is determined.

【0028】

Similarly, the second switch signal I²The connection state of the first switch SW1 is determined by C2, and the first switch signal I²C1 determines the connection status of the 3rd switch SW3. In this way, in order to select each of the switches SW1, SW2, SW3, the signals A and I output from the microcomputer 240.²C1, I²Multiple modes are set according to the logical state of C2, and when the viewer selects the corresponding mode, as shown in Fig. 4, the television screen shows the television image (mode 1) and the personal computer image (mode 2). , A two-screen image (mode 3) consisting of the main image and the sub image of the television, or a two-screen image (mode 4) consisting of the personal computer image and the main screen of the television is displayed, respectively.

【0029】

Hereinafter, the operation of the switch unit 270 according to each mode will be described. In the case of mode 1, that is, when only the television image is displayed, the first switch signal I²The terminal P6 of the third switch is selected by C1, and the synchronization signals Hm and Vm are supplied to the deflection unit 280. Further, the second switch signal I²The terminal P2 of the first switch SW1 is selected by C2, the terminal P3 of the second switch SW2 is selected by the third switch signal YS'of the switch control unit 250, and the main brightness signal Hm and the main color decoding signal Um, When Vm is applied to the first matrix 290, the first matrix unit 290 converts the respective signals Hm, Um, Vm into color signals R, G, B and outputs them to the RGB amplifier 108, and the deflection The television image signal is displayed on the television receiver via the brown tube 109 due to the deflection current of the unit 280.

【0030】

In the case of mode 2, that is, when only the personal computer image is displayed, the terminal P5 of the third switch SW3 is selected, the personal computer synchronization signals Hp and Vp are supplied to the deflection unit 280, and the first switch SW1 The terminal P1 and the terminal P3 of the second switch SW2 are selected, and the personal computer decoding signals Yp, Up, Vp are supplied to the first matrix unit 290.

【0031】

In the case of mode 3, that is, when a two-screen image consisting of the main screen and the sub screen of the television is displayed, the terminal P6 of the third switch SW3 is selected, so that the main synchronization signals Hm and Vm are deflected. The terminal P4 of the second switch SW1 is selected and the two-screen decoding signals Ydw, Udw, and Vdw output from the two-screen control unit 230 are supplied to the first matrix unit 290.

【0032】

In the case of mode 4, that is, when the two-screen image consisting of the personal computer image and the main screen of the television is displayed, the terminal P6 of the third switch SW3 is selected, so that the main synchronization signals Hm and Vm are deflected. The horizontal synchronization signal Hm supplied to unit 280 becomes a composite synchronization signal Hc of the synchronization signal conversion unit 263 output via the audio / video switch 101 and the main screen decoder 210, and is subsequently used in mode 4. The synchronization signal becomes the combined synchronization signal Hc.

【0033】

Next, the terminal P1 of the first switch SW1 is selected, and in that state, the second switch SW2 selects the terminal P3 during the first half cycle of the combined synchronization signal Hc, and the combined synchronization signal. Since the terminal P4 is selected during the other half cycle of Hc, the personal computer image selected by the terminal P3 of the second switch SW2 is displayed on the half screen of the television receiver, and the other half screen is displayed. Displays the television image selected by the terminal P4 of the second switch SW2.

【0034】

Hereinafter, the operation of the switch control unit 250 in mode 4 will be described with reference to FIGS. 2 to 3. The control signal A of the microcomputer 240 is usually in the low state. The two-screen selection signal YSdw of the two-screen control unit 230 is in a low state during the horizontal blanking section (H BLK) of the composite synchronization signal Hc, and is in a high state in the other sections.

【0035】

Moreover, when the two-screen selection signal YSdw input to the switch control unit 250 is in the high state at the time T1 when the horizontal blanking section (H BLK) ends, the output signal / Q1 of the multivibrator 251 becomes the resistor R1. And the time constant determined from the capacitor C1 puts it in the low state for a predetermined time and converts it to the high state at the time point T2.

【0036】

Further, the selection signal control unit 252 inverts the output signal / Q1 and outputs the signal. That is, when the output signal / Q1 is in the low state, the two-screen selection signal YSdw is output to the third switch signal YS'via the resistor R2 and the diode D1, but the output signal / Q1 is in the high state. In this case, the level of the third switch signal YS'is the ground level. As shown in FIG. 2, the selection signal control unit 252 that operates in this way is composed of three switching transistors Q1, Q2, and Q3, but can also be configured by other switching means.

【0037】

Further, as shown in FIG. 3, when the third switch signal YS'is in a high state in T1 to T2 during the first half cycle and the terminal P3 of the second switch SW2 is selected, television. A personal computer image is displayed on the left side of the screen, and a television image is displayed on the right side. On the other hand, the frequency band of the television image of the first embodiment of the present invention is about 2 to 3 MHz, and when the image mode used in the personal computer is the VGA mode, the frequency band of the VGA mode is about 20 MHz. That is, the frequency of the horizontal sync signal Hp of the personal computer image is 31.5 kHz, which is about twice the frequency of the television horizontal sync signal Hm. At this time, one cycle is about 31.7 μs, and the personal computer image is displayed during that time. Then, during the next 31.7 μs, the processed television image is displayed on two screens.

【0038】

That is, in the combined synchronization signal Hc used as the synchronization signal of mode 4, assuming that one cycle 1T excluding the horizontal blanking section is 63.5 μs for convenience of explanation, it is between half sections (31.7 μs) of the section 1T. Is set so that the output signal / Q1 is in the low state and the other half section is in the high state. That is, the time constant (τ) of the multivibrator 251 is set as follows so that the half period of the combined synchronization signal Hc is 0.5T.

【0039】

τ = 0.7R₁C₁= 0.5YS In this way, the personal computer video signals Yc, Uc, and Vc are processed on two screens during the half cycle (31.7 μs) of the composite synchronization signal with one cycle of 63.5 μs, and during the remaining half cycle (31.7 μs). The second switch SW2 is switched so that the television image signals Ydw, Udw, and Vdw are input to the first matrix unit 290, and the personal computer image is displayed on the left side of the screen and the television image is displayed on the right side. Is displayed.

【0040】

[Effect of the invention]

As described above, in the simultaneous display device for the television image and the personal computer image according to the present invention, the personal computer image is separately processed without using the conventional two-screen control unit in a narrow frequency band, and the high-resolution personal computer image is processed. In addition, since the television image is divided into two screens at the same time for viewing, the viewer can simultaneously view the high-resolution television image and the personal computer image on one screen.

[Simple explanation of drawings]

[Figure 1]

It is a block diagram which showed the simultaneous display device of the television image and the personal computer image which concerns on this invention.

[Figure 2]

It is a circuit diagram of the switch control unit 250 shown in FIG.

[Fig. 3]

It is each signal timing diagram at the time of simultaneous display of a personal computer image and a television image of FIG.

[Fig. 4]

It is a figure which showed the switching state of the switch SW1, SW2, SW3 of the RGB interface according to each screen mode.

[Fig. 5]

It is a block diagram of a television system that can display two screens in the past.

[Explanation of symbols]

101 ... Audio / Video Switch 102 ... 1st comb filter 103 ... 2nd comb filter 108 ... RGB color signal amplifier 109 ... CRT 210 ... Main screen decoder 220 ... Sub screen decoder 230 ... 2 screen control unit 240 ... Microcomputer 250 ... Switch control unit 251 ... Multivibrator 252 ... Selection signal control unit 260 ... PC signal processing unit 261 ... Part 2 Matrix 262 ... Synchronous signal detector 263 ... Synchronous signal converter 270 ... Switch section 280 ... deflection part 290 ... Part 1 Matrix