JPS59110282A - Special effect waveform generator - Google Patents

Abstract

PURPOSE:To generate a special effect waveform effectively by multiplying a basic wave by a coefficient, switching the coefficient by a switching signal, and varying a horizontal/vertical aspect ratio. CONSTITUTION:Horizontal and vertical synchronizing saw-tooth wave generating circuits 9 and 10 generate saw-tooth wave signals, which are added together by an adding circuit 11, whose output is compared with a specific value by a comparing circuit 12 to obtain switching signals phi1 and phi2. Those switching signals phi1 and phi2 are in inverse relation; when the output of a switching circuit 3 is H, the output of a switching circuit 4 is V. The outputs of the circuits 3 and 4 are multiplied by (a) and (b) at coefficient multiplying circuits 5 and 6 respectively, and the results are added together by an adding circuit 7. Therefore, waveforms are selected by the switching signals phi1 and phi2 to obtain a special effect signal.

Description

[Detailed description of the invention] The present invention relates to television special effects waveform generators.

Television special effects waveforms were obtained by mixing horizontal and vertical special effects waveforms and slicing them at predetermined levels of seven-eder control voltages. However, conventional television special effect waveform generators of this type use limited types of horizontal and vertical fundamental waves, and are therefore limited in the types of waveforms they can generate.

An object of the present invention is to provide a special effect waveform generator that can generate a large number of special effect waveforms by using a limited fundamental wave and adding some processing to it.

In the present invention, the fundamental waves of the horizontal and vertical periods are switched by the switching signal and inputted to the first and second coefficient multiplication circuits, so that the fundamental waves of the horizontal and vertical periods are multiplied. The coefficients are changed, and the first addition circuit adds the outputs of the coefficient multiplication circuit. In the waveform shaping circuit, the output of the first adding circuit is compared with the fader control data to output a special effect waveform signal, and the switching signal is obtained by adding horizontal and vertical periodic sawtooth waves in the second adding circuit. It is obtained by comparing the set value with a comparison circuit.

Next, the present invention will be described in detail with reference to the drawings of an embodiment of the present invention. FIG. 1 is a diagram showing an embodiment of the present invention, in which the output f:H of a horizontal periodic fundamental wave generation circuit 1.

The output of the vertical periodic fundamental wave generation circuit 2 is V, and these are respectively connected to the first switching circuit 3. The second switching circuit 4 switches complementary signals to φ1. φ2, the multiplication coefficient of the first coefficient multiplication circuit 5 that changes the level of the output of the first switching circuit 3 is set to a, the second
The function and operation of each component will be explained in order, assuming that the multiplication coefficient of the second coefficient multiplication circuit 6 that changes the output level of the switching circuit 4 is b. In the figure, the outputs of the multiplication circuits 5.6 are added by a first addition circuit, and further compared with fader control data Df by a waveform shaping circuit 8, and a special effect waveform signal is output. The switching signal is generated by the comparison circuit 12, but for this purpose, horizontal and vertical sawtooth waves are generated by the sawtooth wave generation circuits 9 and 1o, these are added by the second addition circuit 11, and the addition results are compared. It is generated by comparing it with the set value Dt in the circuit 12.

First, the switching signal φ1. φ The method of snow generation is described below. Sawtooth waves having the level shown in FIG. If this output is represented by equal level lines, the second
As shown in Figure (b), the comparison circuit 12 compares the switching signals φl and φ2 with the set value (O in this embodiment).
I am getting . Here, φl and φ2 are in an inverse relationship.
When the output of the switching circuit 3 is H, the output of the second switching circuit 4 is V, and when the output of the first switching circuit 3 is V, the output of the second switching circuit 4 is H. . Next, the outputs of the switching circuits 3 and 4 are multiplied by a and 5 in first and second coefficient multiplication circuits 5 and 6, respectively, and added in a first addition circuit 7. Therefore, as the output of the adder circuit 7, the following two values are selected by the switching signal and output.

Hxa+V+b・・・・・・・・・・・・・・・
...For group...old...(1) Hxb+Vxa
・・・・・・・・・・・・Dan・Old・River・Old and old・・・・
・-(2) Here, let the fundamental waves H and ■ be parabolic waves and a
) b, the output of the waveform shaping circuit 8 will have a solid-line ellipse as shown in FIG.
) is selected, an ellipse of the line is output. Therefore, by selecting the waveform using the switching signals φl and φ snow, the special effect waveform shown by diagonal lines can be obtained. Furthermore, by using triangular waves as the fundamental waves H and V, a special effect waveform shown by diagonal lines in FIG. 4 can be obtained.

As explained above, the present invention multiplies the fundamental wave by a coefficient to change the aspect ratio of the waveform, and changes the horizontal and vertical aspect ratios by switching the coefficient with an appropriate switching signal. It has the effect of generating an effect waveform.

[Brief explanation of drawings]

Figure 1 is a block diagram showing one embodiment of the present invention, Figure 2
(a) is the waveform generated by the horizontal and vertical periodic sawtooth wave generation circuit, (b) is a diagram showing the output of the second adder circuit with equal level lines, and Figure 3 is the case when a parabolic wave is used as the fundamental wave. FIG. 4 shows a special effect waveform when a triangular wave is used as the fundamental wave. In the figure, 1... horizontal periodic fundamental wave generation circuit, 2...
...Vertical periodic fundamental wave generation circuit, 3...1st
switching circuit, 4... second switching circuit, 5...
. . . first coefficient multiplication circuit, 6 . . . second coefficient multiplication circuit, 7 . . . first addition circuit, 8 . . .
... Waveform shaping circuit, 9 ... Horizontal period sawtooth wave generation circuit, 10 ... Vertical period sawtooth wave generation circuit,
11...Second addition circuit, 12...Comparison circuit. Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] A horizontal fundamental data generation circuit that generates horizontal period fundamental wave data, a vertical fundamental data generation circuit that generates vertical period fundamental wave data, and reception of the horizontal and vertical fundamental wave data are switched in a complementary manner by a switching signal. first and second switching circuits that receive the outputs of the two switching circuits and multiply the respective data by coefficients; and first and second coefficient multiplication circuits that receive the outputs of the two coefficient multiplication circuits. a first adder circuit that performs addition; a waveform shaping circuit that receives the output of the adder circuit, compares it with fader control data, and outputs a special effect waveform signal; and a waveform shaping circuit that generates horizontally periodic sawtooth wave data. a horizontal sawtooth wave generation circuit; a vertical sawtooth wave generation circuit that generates vertically synchronized sawtooth wave data; a second addition circuit that receives and adds the horizontal and vertical sawtooth wave data; A special effect waveform generator comprising: a comparison circuit that compares the output of the adder circuit with a set value and supplies the switching signal.