JPH038632B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a novel video effect device that reduces the amount of information in an analog color signal of a television receiver or the like to create a special color video effect.

BACKGROUND ART Conventionally, in order to demodulate a video signal from a television receiver or the like and reproduce a video having a color different from that of the video from the television receiver, the analog video signal that constitutes the demodulated signal is A configuration for converting into values is known.

In the prior art having such a configuration, the video signal obtained by combining the demodulated signals is binarized, so the amount of information in the original analog video signal is considerably reduced. Therefore, when an image is reproduced using a binarized signal, the color of the image is considerably different from the color of the original image, and the aesthetic appearance is impaired, so that it cannot be said to be a special image.

Purpose An object of the present invention is to provide a novel video effect device that improves the aesthetic sense and is also capable of producing special video effects of the color.

Structure of the Invention The present invention includes (a) a DC power supply, and (b) a color signal generation circuit 1 that generates three color signals R, G, and B from a video signal and drives a cathode ray tube 1.
1, and (c) first voltage dividing resistors R1, R10, R for each color connected in series, each of which is supplied with the color signals R, G, and B for driving the cathode ray tube.
19 and second voltage dividing resistors R2, R11, R20
Level conversion circuits 12A, 13A, 14 comprising
(d) emitter follower circuits 12B, 13B, and 14B provided for each of the color signals R, G, and B; (d1) the first voltage dividing resistors R1, R10, and R19, and the second voltage dividing resistor. R2, R11, R20
The first transistor Q1, Q5, Q9 for each color, whose base is given the output from the connection point of
(d2) third resistors R3, R12 for each color connected between the emitters of the first transistors Q1, Q5, Q9 and one terminal of the DC power supply;
(d3) such emitter follower circuits 12B, 13B, 14B that derive an emitter follower output from the emitter of the first transistor; (e) a difference provided for each of the color signals R, G, and B; The dynamic amplifier circuits 12C, 13C, 14C include (e1) second transistors Q2, Q6, for each color, whose bases are given the emitter follower outputs;
Q10, and (e2) the second transistors Q2, Q6, Q10.
and a third transistor Q3, Q for each color, whose emitters are commonly connected to the emitters of the second transistors Q2, Q6, Q10.
7, Q11, and (e3) the second transistors Q2, Q6, Q10.
a fourth resistor R4, R1 for each color connected between the collector of and the other terminal of the DC power supply;
3, R22, and (e4) the third transistor Q3, Q7, Q11
a fifth resistor R5, R1 for each color connected between the collector of and the other terminal of the DC power supply;
4, R23, and (e5) the second and third transistors Q2, Q
A sixth resistor R6, R for each color is connected between the commonly connected emitters of 6, Q10, Q3, Q7, and Q11 and one terminal of the DC power supply.
(e6) the second transistors Q2, Q6, Q10;
collector and the fourth resistor R4, R13, R
The output is derived from the connection point with 22. Such differential amplifier circuits 12C, 13C, 14C
and (f) having variable resistors R7, R16, and R25 for each color that divide the voltage of the DC power supply, and applying the divided DC voltage to the bases of the third transistors Q3, Q7, and Q10 as a discrimination level. Discrimination level setting circuits 12D, 13D,
14D; and (g) a circuit 20 that creates a video signal based on each output from the differential amplifier circuits 12C, 13C, and 14C.

Embodiment FIG. 1 is an electrical circuit diagram of an embodiment of the present invention. Terminals R, G, and B, which are color signal input terminals of the cathode ray tube 1, are terminals 2, 3, and 4 of the CRT board 11.
are connected to each. What is CRT?
It is an abbreviation for Ray Tube. Further, the heater H of the cathode ray tube 1 is connected to terminals 5 and 6 of the CRT board 11. In the CRT board 11, terminals 6 and 7 are grounded, that is, connected to one terminal of a DC power supply,
Terminal 8 is connected to the base of transistor Q9 through resistor R19, terminal 9 is connected to the base of transistor Q5 through resistor R10, and terminal 10 is connected to the base of transistor Q5 through resistor R10.
is connected to the base of a first transistor Q1 via a resistor R1 which is a first voltage dividing resistor. This CRT board 11 has terminals 2, 3,
4 are commonly connected to terminals 10, 9, and 8, respectively, and are given color signals for each color.

In the circuit 12 that converts an analog color signal into a binary signal, the base of the transistor Q1 is connected via a resistor R2, which is a second voltage dividing resistor. The emitter of the transistor Q1 is grounded through a third resistor R3 and connected to the base of the second transistor Q2. A power supply voltage VB is applied to the collector of the transistor Q1 from the other terminal of the DC power supply via a line l1.
The emitter of transistor Q2 is grounded via a resistor R6, which is a sixth resistor, and connected to the emitter of transistor Q3, which is a third transistor.
The collector of transistor Q2 is connected to line l1 via a fourth resistor, resistor R4, and to the base of transistor Q4. The base of transistor Q3 is connected to the variable resistance terminal of variable resistor R7. The collector of transistor Q3 is connected to line l1 via a fifth resistor, R5. A terminal of variable resistor R7 is connected to line l1 and ground. The emitter of transistor Q4 is connected to line l1 via resistor R8. The collector of transistor Q4 is grounded via resistor R9, and is also connected to the input terminal of buffer circuit 15. The output terminal of the buffer circuit 15 is terminal R.
0 and the signal from this output terminal is connected to circuit 1
The output will be 2.

This circuit 12 includes a level conversion circuit 12A, an emitter follower circuit 12B, a differential amplifier circuit 12C, a discrimination level setting circuit 12D, an inverting amplifier circuit 12E,
and a buffer circuit 15.

The circuit 13 includes a level conversion circuit 13A, an emitter follower circuit 13B, a differential amplifier circuit 13C, a discrimination level setting circuit 13D, an inverting amplifier circuit 13E, and a buffer circuit 16. Transistor Q5
The base of is grounded via a resistor R11. The emitter of transistor Q5 is grounded via resistor R12 and is also connected to the base of transistor Q6. Power supply voltage VB is applied to the collector of transistor Q5 via line l2. The emitter of transistor Q6 is grounded via resistor R15 and connected to the emitter of transistor Q7. The collector of transistor Q6 is connected to resistor R13.
is connected to line l2 via a line I2 and to the base of transistor Q8. transistor Q7
The base of is connected to the variable resistance terminal of variable resistance R16. The collector of transistor Q7 is connected to line l2 via resistor R14. The other terminals of variable resistor R16 are connected to line l2 and ground, respectively. The collector of transistor Q8 is grounded via resistor R18 and also connected to the input terminal of buffer circuit 16. The output terminal of the buffer circuit 16 is connected to the terminal G0, and the signal from this output terminal becomes the output of the circuit 13.

The circuit 14 includes a level conversion circuit 14A, an emitter follower circuit 14B, a differential amplifier circuit 14C, a discrimination level setting circuit 14D, an inverting amplifier circuit 14E, and a buffer circuit 17. Transistor Q9
The base of is grounded via resistor R20. The emitter of transistor Q9 is grounded via resistor R21, and is also connected to the base of transistor Q10. Power supply voltage VB is applied to the collector of transistor Q9 via line l3. The emitter of transistor Q10 is grounded via resistor R24 and connected to the emitter of transistor Q11. The collector of transistor Q10 is connected to line 13 via resistor R22 and to the base of transistor Q12. The base of transistor Q11 is connected to the variable resistance terminal of variable resistor R25. The collector of transistor Q11 is connected to line l3 via resistor R23. The other terminal of variable resistor R25 is connected to line l3.
and ground, respectively. transistor Q
The collector of 12 is grounded via a resistor R27, and is also connected to the input terminal of the buffer circuit 17. The output terminal of the buffer circuit 17 is connected to the terminal B0, and the signal from this output terminal becomes the output of the circuit 14.

In other words, the CRT board 1 which is a color signal generation circuit
Color signals R, G, and B for driving the cathode ray tube 1 are derived from terminals 9, 10, and 11 of the cathode ray tube 1, respectively. For each color signal R, G, B, level conversion circuits 12A, 13A, 14A, emitter follower circuits 12B, 13B, 14B, differential amplifier circuit 12C,
13C, 14C and discrimination level setting circuit 12
D, 13D, and 14D are provided, respectively.

The operation of the circuit shown in FIG. 1 will be described below with reference to the waveform diagram shown in FIG. A circuit is mounted on the CRT board 11 to reproduce video signals sent from a television broadcasting station or the like and to provide color signals to the cathode ray tube. An analog red color signal is sent from terminal 2 of the CRT board 11, a green color signal is sent from terminal 3, and a blue color signal is sent from terminal 4. An image is reproduced on the cathode ray tube 1 using these red, green, and blue color signals. Further, from terminals 8 to 10 of the CRT board 11, transistors Q1,
Each color signal close to the operating level of Q5 and Q9 is sent out. A red color signal is sent from the terminal 10 of the CRT board 11, and the red color signal is applied to the level conversion circuit 12A of the circuit 12. The level conversion circuit 12A lowers the level of the received red color signal to the operating level of the transistor Q1 of the emitter follower circuit 12B. This level-down red color signal is given to the differential amplifier circuit 12C via the emitter follower circuit 12B. The signal applied to this differential amplifier circuit 12C becomes a signal P1 as shown in FIG. 2. Discrimination level setting circuit 12D
The volume R7 is used to set the base potential of the transistor Q3, that is, to preset the discrimination level of the differential amplifier circuit 12C.
If this discrimination level is set to line P2 shown in FIG. 2, a pulse signal P3 shown in FIG. 2 is sent out from the differential amplifier circuit 12C. Differential amplifier circuit 12
In C, when the signal P1 exceeds the discrimination level P2, the pulse signal P3 becomes low level, and the signal P
1 is less than the slice level P2, the pulse signal P
3 is high level. The pulse signal P3 shown in FIG. 2, which is the output of the differential amplifier circuit 12C, is given to the inverting amplifier circuit 12E, which inverts the pulse signal P3 and sends out the pulse signal P4 shown in FIG. 2. . The pulse signal P4 is buffered by the buffer circuit 15 and applied to the terminal R0. A TTL level digital signal corresponding to the information of the red color signal is sent from the terminal R0. TTL stands for transistor-transistor logic.

An analog green color signal is sent from the terminal 9 of the CRT board 11, and the green color signal is applied to the level conversion circuit 13A of the AD conversion circuit 13. The level conversion circuit 13A lowers the level of the received green color signal to the operating level of the transistor Q5 of the emitter follower circuit 13B. This level-down green color signal is transmitted to the emitter follower circuit 13.
It is applied to the differential amplifier circuit 13C via B. It is assumed that the signal applied to the differential amplifier circuit 13C is, for example, the signal P1 in FIG. 2, which is similar to that described above. Variable resistor R of discrimination level setting circuit 13D
Reference numeral 16 presets the discrimination level of the differential amplifier circuit 13C. If this discrimination level is, for example, line P2 in FIG. 2, the differential amplifier circuit 13C compares the signal P1 with the discrimination level P2 and sends out the pulse signal P3 in FIG. 2. This pulse signal P3 is applied to an inverting amplifier circuit 13E, which inverts the pulse signal P3 and sends out a pulse signal P4 shown in FIG. 2. The pulse signal P4 is buffered by the buffer circuit 16 and applied to the terminal G0. From terminal G0, TTL corresponding to green color signal information is output.
A level digital signal is sent out.

An analog blue color signal is sent from the terminal 8 of the CRT board 11, and the blue color signal is applied to the level conversion circuit 14A of the AD conversion circuit 14. The level conversion circuit 14A lowers the level of the received blue color signal to the operating level of the transistor Q9 of the emitter follower circuit 14B. This level-down blue color signal is transmitted to the emitter follower circuit 14.
It is applied to the differential amplifier circuit 14C via B. It is assumed that the signal applied to the differential amplifier circuit 14C is, for example, the signal P1 in FIG. 2, which is similar to that described above. Volume R of discrimination level setting circuit 14D
Reference numeral 25 presets the discrimination level of the differential amplifier circuit 14C. If this discrimination level is, for example, line P2 in FIG. 2, the differential amplifier circuit 14C compares the signal P1 with the discrimination level P2 and sends out the pulse signal P3 in FIG. 2. This pulse signal P3 is applied to an inverting amplifier circuit 14E, which inverts the pulse signal P3 and sends out a pulse signal P4 shown in FIG. 2. The pulse signal P4 is buffered by the buffer circuit 17 and applied to the terminal B0. From terminal B0, TTL corresponding to the information of the blue color signal is output.
A level digital signal is sent out.

The video conversion device 20 converts a binary signal corresponding to the information of the red color signal from the terminal R0 to the terminal G0.
A digital signal corresponding to the information of the green color signal from the terminal B0 and a binary signal corresponding to the information of the blue color signal from the terminal B0 are received, respectively, and a video signal is created. Since this video signal has a reduced amount of information compared to the analog color signal from the CRT board 11, it produces a special image effect different from the color of the original image.

As described above, the video conversion device 20 creates a video signal based on the binarized signal for each color, and the video signal thus created from the video conversion device 20 is transmitted to a separately provided cathode ray tube or the like. Display in color.

Effects As described above, according to the present invention, 3
It generates three color signals R, G, and B, and converts each color signal R, G, and B into one level and the other level by differential amplifier circuits 12C, 13C, and 14C at individually variable discrimination levels. Level discrimination and 2
Since the video signal is created based on the binarized color signal for each color, there is no problem that the amount of information in the original video signal is excessively reduced, and the amount of information for each color is This makes it possible for the first time to create special video effects that differ from the colors of the original image without sacrificing aesthetics.

In these differential amplifier circuits 12C, 13C, 14C,
Since the color signals are binarized by giving the discrimination levels from the discrimination level setting circuits 12D, 13D, and 14D, it is easy to freely adjust and set the change in the discrimination level for each color signal. This makes it possible to create special video effects.

The bases of the second transistors Q2, Q4, Q10, which are the input terminals of the differential amplifier circuits 12C, 13C, 14C, are connected to the emitter follower circuits 12B, 13B,
Level conversion circuits 12A, 13A,
Connected to 14A. Emitsuta follower circuit 1
Since 2A, 13A, and 14A have high input impedance and low output impedance, a load with high input impedance is connected to level conversion circuits 12A, 13A, and 14A.
Therefore, the first and second voltage dividing resistors R1, R1
0, R19; Resistors having high resistance values can be used as R2, R11, and R20. As a result, level conversion circuits 12A, 13A, 14A
The input impedance of the color signal generating circuit 11 is also increased, and the influence on the driving of the cathode ray tube 1 in the color signal generating circuit 11 can be reduced. In addition, first voltage dividing resistors R1, R10, R19 and second voltage dividing resistors 2, R1
The color signals R, G, and B are divided at the partial pressure ratio of 1 and R20, and the emitter followers 12B and 13 are divided.
Differential amplifier circuits 12C and 13 via B and 14B
Therefore, the level of each color signal R, G, B in the color signal generation circuit 11 can be easily converted to a suitable input level to the differential amplifier circuits 12C, 13C, 14C. can.

The differential amplifier circuits 12C, 13C, 14C include a pair of second and third transistors Q2, Q6, Q1.
0: Has constant current characteristics due to the sixth resistor connected in series to the commonly connected emitters of Q3, Q7, and Q11. second and third transistors Q2,
Q6, Q10; fourth and fifth resistors R4, R1 between the collectors of Q3, Q7, Q11 and the DC power supply
3, R22; R5, R14, and R21 are connected to each other, and the circuit has good symmetry. In this way, the differential amplifier circuits 12C, 13C, and 14C have good balance, and are therefore less susceptible to fluctuations in temperature and power supply voltage. Therefore, even when a video effect device is installed inside a television receiver, for example,
Internal temperature is less affected by fluctuations in power supply voltage.

Furthermore, according to the present invention, the discrimination level is set in the differential amplifier circuit 12 by variable resistors R7, R16, and R25.
It is applied to the bases of third transistors Q3, Q7, and Q11 that constitute C, 13C, and 14C. Each signal R, G, B is connected to the second transistor Q2, Q6, Q
10 base and derived from its collector. Since the bases of the third transistors Q3, Q7, and Q11 are not in the transmission paths of the color signals R, G, and B, even if the connection lines are extended, the influence on the signals is small. Therefore, variable resistors R7, R16, R
25 can be provided at a position away from the differential amplifier circuits 12C, 13C, and 14C and at a position where it is easy to operate.

[Brief explanation of the drawing]

Fig. 1 is an electrical circuit diagram of an embodiment of the present invention;
The figure is a waveform diagram for explaining the operation of the electric circuit of FIG. 1. 1... Braun tube, 11... CRT board, 12
~14...circuit, 12C~14C...differential amplifier circuit.

Claims (1)

[Claims] 1: (a) a DC power supply; (b) a color signal generation circuit 1 that generates three color signals R, G, and B from a video signal and drives a cathode ray tube 1;
1, and (c) first voltage dividing resistors R1, R10, R for each color connected in series, each of which is supplied with the color signals R, G, and B for driving the cathode ray tube.
19 and second voltage dividing resistors R2, R11, R20
Level conversion circuits 12A, 13A, 14 comprising
(d) emitter follower circuits 12B, 13B, and 14B provided for each of the color signals R, G, and B; (d1) the first voltage dividing resistors R1, R10, and R19, and the second voltage dividing resistor. R2, R11, R20
The first transistor Q1, Q5, Q9 for each color, whose base is given the output from the connection point of
(d2) third resistors R3, R12 for each color connected between the emitters of the first transistors Q1, Q5, Q9 and one terminal of the DC power supply;
(d3) such emitter follower circuits 12B, 13B, 14B that derive an emitter follower output from the emitter of the first transistor; (e) a difference provided for each of the color signals R, G, and B; The dynamic amplifier circuits 12C, 13C, 14C include (e1) second transistors Q2, Q6, for each color, whose bases are given the emitter follower outputs;
Q10, and (e2) the second transistors Q2, Q6, Q10.
and a third transistor Q3, Q for each color, whose emitters are commonly connected to the emitters of the second transistors Q2, Q6, Q10.
7, Q11, and (e3) the second transistors Q2, Q6, Q10.
a fourth resistor R4, R1 for each color connected between the collector of and the other terminal of the DC power supply;
3, R22, and (e4) the third transistor Q3, Q7, Q11
a fifth resistor R5, R1 for each color connected between the collector of and the other terminal of the DC power supply;
4, R23, and (e5) the second and third transistors Q2, Q
6, Q10; Sixth resistor R6, R for each color connected between the commonly connected emitters of Q3, Q7, Q11 and one terminal of the DC power supply
(e6) the second transistors Q2, Q6, Q10;
collector and the fourth resistor R4, R13, R
The output is derived from the connection point with 22. Such differential amplifier circuits 12C, 13C, 14C
and (f) having variable resistors R7, R16, and R25 for each color that divide the voltage of the DC power source, and applying the divided DC voltage to the bases of the third transistors Q3, Q7, and Q10 as a discrimination level. Discrimination level setting circuits 12D, 13D,
14D; and (g) a circuit 20 that creates a video signal based on each output from the differential amplifier circuits 12C, 13C, and 14C.