JPS6034307B2 - Video special effect signal generator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a video special effect signal generation device employed in video transmission calendars used in television broadcasting stations, and more particularly to a rotation wipe key signal generation device.

There are many types of key signals for wiping a TV screen, but most of them simply move the wipe boundary line in a parallel or expanding direction. Typical examples include circular wipe, diamond wipe, and vertical wipe. , vertical wipe, horizontal wipe, corner wipe, etc.

In addition to these wipes, there is a method of rotating the border line around a certain point, but it has not been widely used because it has the disadvantage that the center part cannot be fixed sufficiently on the screen.

A conventional circuit system for obtaining a rotary wipe will be described below with reference to FIG.

Reference numerals 1 and 2 are horizontal and vertical fundamental wave generation circuits, in which sawtooth waves, triangular waves, etc. having respective periods are generated.

In order to make the content easier to understand, the following explanation will focus on the example of a sawtooth wave, and cases of other waveforms such as a triangular wave will be explained as necessary, but essentially they are all the same. 3 and 4 are bell regulators, which are expressed here as variable resistors for convenience, but of course other circuit systems may be used.

5 is a mixing circuit that mixes and adds horizontal and vertical fundamental waves that have been adjusted by a bell, and this output is sliced at a specific level by a slicing circuit 6 to generate a key signal for wiping.

The key signals created in step 6 are two television video signals V^, V
It is added to the selection gate circuit 8 of B, where the screen is switched according to the key signal, and a signal Vo is created in which one image is filled with the other image by a predetermined wipe pattern.

Here, it is the level adjusters 3 and 4 that cause the wipe boundary line on the screen to rotate.

This relationship will be explained using the waveform in FIG. 2 and the effect on the screen in FIG. 3. Here, in order to make the explanation easy and accurate in the following explanation, the horizontal and vertical fundamental waves are expressed as WH and Wv, their mixed fundamental wave WHv, and the gate key signal obtained by slicing them are expressed as WK. . In FIG. 2, when the horizontal fundamental wave WH and the vertical fundamental wave Wv are mixed with the same amplitude, a mixed fundamental wave W shown by the solid line in the waveform diagram a is obtained.

Here, the horizontal and vertical time ratios in Figure 2 are exaggerated compared to reality. When this mixed fundamental wave WHv is sliced at the slice level Ls, the waveform shown in FIG. 2b is obtained as the key signal WK.

When the switching circuit 8 is controlled by this b waveform and the signal obtained as the output Vo is expressed on the screen, it becomes as shown in Fig. 3.
, B The two television screens are separated by a boundary line indicated by a solid line. Next, when the level adjusters 3 and 4 increase or decrease the horizontal fundamental wave WH and the vertical fundamental wave Wv in opposite directions, for example, the horizontal fundamental wave WH increases and the vertical fundamental wave Wv
When the fundamental wave W is decreased, as shown by the dotted line in the waveform diagram a, the fundamental wave W
Hv' is obtained, and in the same way, the key signal WK' is shown in the waveform diagram c.
obtained as follows.

Here, if we look at the phase of the rising part that creates a wipe boundary line between key signals WK and WK', at the top of the screen, that is, to the left of the waveform diagram, key signal WK' is to the left of WK, and at the bottom of the screen, key signal WK' is to the left of WK. ' is to the right of WK, and it does not move at point P in the center of the screen. Therefore, the boundary line in Figure 3 is P
Rotate around the point as indicated by the dotted line. This is the basic principle of rotary wipe. However, the rotation center point P cannot always be stably obtained.

This will be explained with reference to FIGS. 4, 5 and 6.

FIG. 4 shows the mixed fundamental wave WHv of FIG. 2 in another representation, that is, in a state where the waveform is monitored at a vertical period on an oscilloscope.

First, the wipe boundary of the screen by the key signal obtained by slicing the waveform a of FIG. 4 at the slice level Ls is the same as that of FIG. 3, and is represented by a in FIG. 5.

Next, by slicing at the slice level Ls using the waveform b obtained by increasing the horizontal fundamental wave WH and subtracting the vertical fundamental wave Wv, the boundary line b in FIG. 5 is obtained. With the same machine, boundary line c in FIG. 5 is obtained corresponding to the waveform in FIG. 4 c. What you need to be careful about here is the Namiai fundamental wave WHv and the slice level L.
In the above explanation, it is assumed that the slice level Ls is always at the center of the amplitude of the mixed fundamental wave WHv, as shown in FIG. However, it is generally surprising that such a state is always maintained. This is because the river level regulators 3 and 4 not only change the horizontal and vertical fundamental waves WH and Wv, which are AC components, but also change the DC component.

In order to avoid this, a fundamental wave generation method can be considered in which the DC components of the '2' horizontal fundamental wave WH and the vertical fundamental wave Wv are made zero, but since the DC components are zero, it is difficult to obtain long-term stability.

(3} Also, from the fundamental wave generation circuits 1 and 2 to the slice circuit 6
It is necessary to use a direct connection method up to the point where it tends to lack stability. '41 It is also possible to use AC coupling without adopting the above direct coupling method and apply a predetermined bias just before the slice circuit 6, but if the rotation is controlled rapidly, transient phenomena will occur and it will take time to settle down. .

For these reasons, it is difficult to maintain stable conditions on a daily basis, even immediately after carefully adjusting the circuit.

As a result, the slice level L for the mixed fundamental wave WHv
The mutual relationship of s changes, and for example, as shown in b and c of FIG. 4, the slice level changes to Ls'. In the example of Fig. 4, as the waveform changes from a to b to c, the relative relationship of the slice level to the mixed fundamental wave WHv becomes Ls', and as a result, the rotation boundary line moves as shown in Fig. 6. The rotation is performed independently of the point P at the center of the screen, and there is no point that is the center of rotation.

The above description has been made of the case where both the horizontal fundamental wave WH and the vertical fundamental wave Wv are sawtooth waves, but the same can be said of the same aircraft in the case of other waveforms as well.

For example, if it is desired to obtain a wipe effect as shown in FIG. 7, a sawtooth wave has been used in the explanation up to now, and a triangular wave may be used as the vertical fundamental wave Wv.

Figures 8, 9, and 1 represent the waveform changes and screen changes in this case in the same way as Figures 4, 5, and 6.
This is figure 0. In this case, the 9th change, which is originally a desirable change,
In order to obtain the rotational movement of the boundary line shown in the figure, unless the relationship between the mixed fundamental wave WHv and the slice level Ls in FIG. 8 is maintained accurately, the center of rotation will shift as shown in FIG. 10. In FIG. 8, the slice level Ls' is shown as an example in which it deviates above Ls, but if it deviates downward, it becomes as shown by the dotted line in FIG. Such defects occur regardless of the fundamental wave, and another example is the 11th wave.
As shown in the figure, the effect that the shaded area spreads in a fan shape around point P can be created by using triangular waves for both the horizontal fundamental wave WH and the vertical fundamental wave Wv, but the mutual relationship between the slice point and the mixed fundamental wave WHv is still If it is not fixed, the tip will become loose as shown in Figure 12.

These things not only make it impossible to obtain the desired wipe screen, but also result in an unsightly wipe screen where the center of rotation is not determined.In addition, in the case of the rotation wipe shown in Figure 12, the wipe screen cannot be moved from one screen to another, which is the purpose of this button. This means that complete conversion to the screen will not be possible. As described above, it is not sufficient to obtain the rotation center P point approximately, but it must be obtained accurately and reliably, but this has been difficult with conventional devices for the reasons mentioned above.

In order to eliminate the above-mentioned drawbacks, a video special effect signal generating device has been proposed that can easily, reliably, and accurately fix the center of rotation and thereby realize a variety of wipe functions.

Hereinafter, an example of a conventional video special effect signal generating device will be described in detail with reference to FIGS. 13 to 20.

The video special effect signal generation device shown in FIG. 13 differs from the conventional video special effect signal generation device described above with reference to FIG. The same parts as those in FIG. Now, the first difference between the device shown in FIG. 13 and the device shown in FIG.
A reference level is inserted into a predetermined section in the process, and level adjustment and mixing are then performed.

The predetermined section referred to here is a section inserted in advance to clamp the fundamental wave or its mixture before slicing, and normally a pulse within the horizontal blanking period is desirable.

Pulse a shown in FIG. 14a is a pulse for creating a predetermined section, and may be a horizontal planking pulse or a horizontal driving pulse.

Figures 14b and 14c show examples of inserting reference pulses when sawtooth waves are selected as the horizontal and vertical fundamental waves, and reference pulses LH and Lv are inserted in each waveform during the period of pulse a. has been done.

Although any means may be used to insert such a bell into the original fundamental wave, the circuit shown in FIG. 15 can be used, for example. Here, the transistor TRI forms an emitter follower, and the original fundamental wave applied to the input appears at its emitter. On the other hand, the transistor TR3 generates a reference level, and a DC voltage determined by the ratio of resistors R2 and R3 is applied to the base, and a DC voltage is applied from the emitter of low impedance to the emitter of the transistor TR2.

This transistor TR2 forms a switching circuit,
When a positive pulse is applied to the base through the capacitor C, it is turned on for that period, and the collector is connected to the transistor TR.
3 to a constant level determined by the DC voltage supplied to the emitter. This level is inserted as a reference level, and during the rest of the period, the original fundamental wave appears at the collector of the transistor TR2 through the resistor RI. Here capacitor C
The pulses coupled via are, of course, the inverted polarity of the pulses shown in FIG. 14a. A transistor TR4 forming an output emitter follower is connected to the collector of the transistor TR2, and a signal is supplied to the next stage via this transistor TR4. The reference level insertion circuit shown in FIG. 15, which was entrusted to us, is an example, and the reference level insertion circuit that has a certain relationship with the original fundamental wave is inserted before processing such as level control on the original fundamental wave. Any means for inserting the information may be used.

As mentioned above, the fundamental waves WH, W with the reference level inserted
v is controlled and further mixed, but this is exactly the same as before.

Next, the second difference between the device shown in FIG. 13 and the device shown in FIG. 10, keep the clamp level at a constant value, and slice at the constant value, that is, the same slice level as the clamp level.

Figure 14d shows the relationship between the mixed fundamental wave WHv and the slice level Ls. Of course, it is a mixture including the above, but by clamping the reference level part as described above,
As a result of slicing at the same slice level Ls, a key signal WK is obtained as shown in FIG.
What is important here is the case where the horizontal fundamental wave WH and the vertical fundamental wave Wv are respectively increased or decreased, and the respective waveforms at that time, that is, WH, Wv, WHv, WK are shown by dotted lines in FIGS. 14b to 14d and f. When the increase or decrease is made in this way, as can be seen from the figure, the slice is sliced at the same slice level Ls as when no increase or decrease is made as shown by the solid line, and this slice level Ls
Since is always the same as the reference level section, no matter how the bell control or mixing is performed, whether the transmission path is directly connected, AC coupled, or even if there are DC fluctuations. , regardless of this, clamping is performed before slicing, so that the waveform relationship shown in FIG. 14d is obtained. This relationship is equivalent to the relationship between the mixed fundamental waves WHv, WHv' and the slice level Ls shown in FIG. 2, and the relationship between the mixed fundamental wave WHv and the slice level Ls shown in FIG. Such a relationship between the mixed fundamental wave WHv and the varied slice level Ls' essentially does not occur.

If the reference pulse is normally inserted within the horizontal line period, its presence will be ignored on the final television screen.

Further, when we examine the device shown in Fig. 13, we find the following interesting things.

FIG. 16 represents each waveform shown in FIG. 14 using another method, and is convenient for understanding the waveform processing by the apparatus shown in FIG. 13.

In other words, Fig. 16 shows the horizontal and vertical fundamental waves WH and Wv shown in Figs. You can see at a glance the relationship between the reference level on the fundamental wave and the center of rotation of the wipe pattern created by the wave-matching fundamental wave in which each fundamental wave is mixed. In this figure, it goes without saying that there are exactly as many reference level cuts in the vertical fundamental wave Wv as there are scanning lines, but they are roughly expressed for convenience of display. As can be seen from Figures 14b and 14c, the rotation center point P on the TV screen corresponds to the timing at which Pv coincides with the point PH where the original fundamental wave and the reference level intersect for each of the horizontal and vertical fundamental waves WH and Wv. is obtained as a point that does not move no matter how the levels of the fundamental waves WH and Wv are controlled.

Therefore, according to the apparatus shown in FIG. 13, by determining the intersection levels PH and Pv between each fundamental wave and the reference level, the rotation center point P of the wipe pattern can be easily determined.

As another example, what happens when the dip pattern shown in FIG. 7 mentioned above is obtained by employing the apparatus shown in FIG. 13 will be explained.

That is, in order to obtain the wipe pattern shown in FIG. 17, the horizontal fundamental wave WH is a sawtooth wave and the vertical fundamental wave Wv is a triangular wave, which is of course the same as before, but the reference level is set as shown in FIG. 17. The horizontal fundamental wave WH is inserted at the lower end of the sawtooth wave, and the vertical fundamental wave Wv is also inserted at the same level as the tip of the triangular backwave. As a result, the intersection points PH and Pv between each fundamental wave and the reference level are at the positions shown in the figure, and the rotation center point on the TV screen that corresponds to the timing when these intersection points PH and Pv coincide is fixed at the center of the left side of the screen. Since the dip boundary changes at the center, the phenomenon of change in the center of rotation as shown in FIG. 10 does not occur.
Similarly, FIG. 18 shows an example in which a triangular wave is applied to the horizontal fundamental wave WH and a sawtooth wave is applied to the vertical fundamental wave Wv.

Furthermore, other waveforms, such as parabolic waves, may be used as the fundamental wave, and as an example, FIG. 19 shows an example in which a parabolic wave is used as the horizontal fundamental wave WH. At this time, the effect is that the parabolic wipe border, which has a fixed center at the bottom center of the screen, expands to the left and right. In addition, as shown in FIG. 20, each fundamental wave WH,
If Wv is a triangular wave and the reference level is set to the middle level of the waveform, the intersection point P of each fundamental wave and the slice level,
Two points are obtained for each Pv, and four points P on the TV screen are obtained.
, ~P4 can be obtained. As described above, according to the apparatus shown in FIG. 13, a reference level is inserted into each predetermined section of the horizontal and vertical fundamental waves, the mixed fundamental wave is pulse-clamped in the predetermined sections, and the slice level is the same as this clamp level. Since the slices are sliced with a , the center of rotation can be easily and reliably fixed, and various rotational effects can be created accurately. Further, when performing waveform processing such as level control, the DC level may be ignored in the design, increasing the degree of freedom in design. Furthermore, even when rapid waveform control is performed, the movement of the center of rotation is hardly visible because it is clamped by horizontal period pulses. However, in the above-mentioned video special effect signal generation device, the level control of each of the horizontal and vertical fundamental waves WH and Wv is performed by controlling either the positive or negative waveform of each waveform from zero to the maximum. Wipe control could only be performed by changing two quadrants from the center of rotation of the wipe pattern on the TV screen.

For example, in the example shown in FIG. 16 described above, the boundary line rotates upward from the horizontal state to the right, and moves only 900 degrees until it becomes vertical. In view of the above circumstances, each horizontal and vertical fundamental wave W
A video special effect signal generating device has been proposed in which the levels of both H and Wv do not change between unidirectional polarities, but level control is performed over positive and negative polarities, thereby providing a wider variety of wipe effects.

An example of the video special effect signal generating apparatus will be described in detail below with reference to FIGS. 21 to 27.

The video special effect signal generating device shown in FIG. 21 differs from the conventional device described above with reference to FIG. 13 in that polarity inverting circuits 13 and 14 and level controllers 15 and 16 are added. However, since the other parts are the same, the same parts in FIG. 21 as those in FIG. The output signals of the reference level insertion circuits 11 and 12 are introduced into the polarity inverting circuits 13 and 14, and output signals of positive and negative polarities are derived.

This output signal is subjected to level control over the positive and negative levels by level controllers 15 and 16, and is guided to the mixer 5. If the polarity of either the horizontal fundamental wave WH or the vertical fundamental wave Wv is reversed with respect to the reference level, a boundary line having an inclination opposite to that of the wipe pattern boundary line shown in FIG. 16 described above is obtained. For example, as shown in FIGS. 22a to 22e, in contrast to FIGS. 14a to 14e, if the vertical fundamental wave Wv is inverted with respect to the reference level, the resulting wipe boundary line will be upward-leftward.

Further, as shown in FIG. 23, when the level of the horizontal fundamental wave WH is changed from the solid line to the dotted line to the region of opposite polarity, the wipe boundary line also changes beyond the horizontal line to the region of reverse slope.
Similarly, the wipe effect when the horizontal fundamental wave WH is a triangular wave or a parabolic wave is shown in FIGS. 24 and 25. If this is further continued and the horizontal and vertical fundamental waves WH and Wv are controlled in mutually opposite directions, it is easy to rotate the boundary line once, and the situation at this time is shown in FIG.

FIG. 26 shows an example of horizontal and vertical fundamental waves WH, Wv and a sawtooth wave, and shows a series of operations from a to h. First, in state a, the vertical fundamental wave Wv is initially zero and the horizontal fundamental wave WH is at its maximum value, so the television screen is vertically divided into two, with image A displayed on the left and image B on the right. Next, the vertical fundamental wave Wv increases and the horizontal fundamental wave WH decreases, so that the boundary line slopes to the right.

Next, when the state moves to state b, the horizontal fundamental wave WH decreases to zero, and the vertical fundamental wave Wv increases to its maximum value, the screen is horizontally divided into two, with images A on the top and B on the bottom.

Next, the state moves to state c, where the horizontal fundamental wave WM reverses the polarity of a and b, increases from zero in that direction, and becomes the vertical fundamental wave W.
v starts decreasing from the maximum value.

A description of the states d to h will be omitted below, but after the state h, the state returns to the state a again, during which time the boundary line has rotated once. Note that FIG. 27 shows another embodiment in which, compared to the configuration shown in FIG. The difference is that amplitude control is performed using the switches 17 and 18, but as can be seen in FIG. 26, the shock that is applied to the wipe pattern when the polarity is changed by switches 17 and 18 is that the level of the horizontal fundamental wave WH or the vertical fundamental wave Wv is zero, that is, Since the polarity is switched only when the output is attenuated to zero by the level controllers 3 and 4, there is no problem.

Furthermore, even if a DC-like fluctuation occurs, it will be absorbed by the aforementioned clamp circuit (10 in FIGS. 13 and 21) and will have no effect. Furthermore, the circuits shown in FIGS. 21 and 27 only show the principle, and each waveform process can be performed accurately and smoothly by using other specific circuits, such as a digital control circuit.

However, in the above-mentioned video special effect signal generation device, the boundary line of the wipe pattern is completely rotated.
It was not possible to generate a so-called fan-shaped wipe pattern having a fixed part and a rotating part as boundaries.

The present invention was made in consideration of the circumstances of Kami Aoki, and is a video special effect signal generating device that can stably generate a wipe pattern that has a fixed part and a rotating part as a boundary line, and can dramatically increase the types of effect waveforms. It provides:

Embodiments of the present invention will be described in detail below with reference to the drawings.

The video special effect signal generating device shown in FIG. 28 has additional clamp circuits 21 and 22, slice circuits 23 and 24, and a logic synthesis circuit 25 compared to the conventional device described above with reference to FIGS. 21 and 27. The same parts as in FIG. 28 and FIG. 21 and FIG. 27 are designated by the same reference numerals, and the explanation thereof will be omitted.

The clamp circuit 21 is connected to the output signal W of the polarity inversion circuit 13.
H is clamped, and the slicing circuit 23 slices the clamp output at the same slice level as the clamp level to obtain a horizontal gate signal Hc.

Similarly, the clamp circuit 22 clamps the output signal Wv of the polarity inversion circuit I4, and the slice circuit 24 slices the clamp output at the same slice level as the clamp level to obtain the vertical gate signal VG.

The slice circuit 6 also generates a key signal WK for generating a wipe that can make one rotation to the right or left as described above with reference to FIGS. 21 and 27.

The output signals of the respective slice circuits 6, 23, and 24 are logically synthesized by the logic synthesis circuit 25, and the wipe pattern obtained by this synthesized output key signal WK' is as shown in FIGS. 29a to 29d, for example.

That is, the effects shown successively in the order of a, b, c, and d in Fig. 29 are a type of fan wipe, but unlike the effects explained with reference to Figs. 21 and 27, they are not fixed. There is a boundary line F.

The diagonal rotating boundary on the TV screen is created by using the horizontal and vertical fundamental waves WH, Wv, which are the basic modes of rotation wipe, and the second wave using the sawtooth wave, as explained with reference to Fig. 26.
It can also be generated in FIG. 8, and in FIG. 29, changes in the fundamental waves WH and Wv are shown below the screens a to d. In order to create the effect signals a to d, a horizontal gate signal indicated by HG in FIG. 29 is further required.
The fixed boundary line F is formed by this gate signal HG. That is, from a to b in Fig. 29, that is, the hatched part A expands from the top to the right, and the rotation boundary is at the center of the lower side and the right half becomes the hatched part A.
The key signal WK generated while changing from a to d in the figure and the gate signal HG are combined under an AND condition, and the keys generated from c to d in FIG. 29 are generated while changing from e to h in FIG. 26. The 29th key signal WK' obtained by roughly combining the signal WK and the gate signal HG under the OR condition
You can get the wipe effect shown in the picture.

Here, the gate signal Ho is a rectangular wave with a horizontal period that rises at the timing of passing through the rotation center point P of the wipe pattern on the TV screen, so each of the horizontal and vertical fundamental waves WH, Wv
It is also possible to create the
Even if the rising phase of c moves, the result is an unsightly wipe effect. However, the device of the present invention avoids such an unsightly wipe effect and can obtain a gate signal Hc that always passes through the rotation center point P.
The gate signal HG for creating the fixed boundary line F is connected to each fundamental wave W.
It is not generated independently of H and Wv, but is obtained by clamping the horizontal fundamental wave WH or vertical fundamental wave Wv as is before performing level control or mixing, and slicing it at the clamp level.

Therefore, the phase of the rising portion of the gate signal Hc is always at the PH point, and as a result, the fixed boundary line F in FIG. 29 passes through the rotation center point P. As described above, the logic synthesis circuit 25 that logically synthesizes the key signal WK for generating the rotating boundary line and the gate signals Hc and Vc for generating the fixed boundary line F has a configuration as shown in FIG. 30, for example. , the phase inversion circuit 26 and the AND/OR synthesis circuit 2
7 and a gate signal selection switch 28, and commands for controlling the combination of these operations are sequentially given from an effect waveform control console (not shown).

Taking as an example a pattern in which the fixed boundary F is a vertical line as shown in FIG. 29, the switch 28 always receives the horizontal gate signal H.
G is selected, the inverting circuit 26 always generates an in-phase output +,
The AND/OR circuit 27 may be controlled so that the screen shown in FIG. 29 performs AND synthesis from a to b, and OR synthesis from c to d.

Note that x indicates AND, 10 indicates OR, and y indicates EX-OR.
(The same applies hereinafter) Also, in the case of an effect having a horizontal fixed boundary line F' as shown in FIG. 31, the switch 28 always selects the vertical gate signal Vc, and the rotating boundary line is in the second and third quadrants on the screen. Logic synthesis of Vc×WK (AND synthesis) may be performed between them, and VG+WK (OR synthesis) may be performed while they are in the fourth and first quadrants.

Furthermore, if the horizontal gate signal HG is selected, the inverting circuit 26 is made to have a negative phase output, and the AND/OR circuit 27 is made to be an exclusive OR circuit, the effect shown in FIG. 32 (Wx due to HG) can be obtained,
Further, the circuit of FIG. 28 using the logic circuit of FIG. 3 in which the AND/OR circuit 27 is an exclusive OR circuit is provided in parallel,
On the other hand, the effect of vertical mode (HG■WK) shown in Figure 32
On the other hand, select the vertical gate signal Vc, generate the transverse mode effect (WK due to Vc) from WH and Wv shown in FIG. 29b, and combine these (WK due to HG) + (V
(G, WK) Then, the effect shown in FIG. 33 is obtained, and by increasing the number of logic synthesis circuits 25 and their inputs, the number of types of effect waveforms can be dramatically increased, and stable ones can be obtained.

The present invention can provide a video special effect signal generating device that can stably generate a wipe pattern having a fixed part and a rotating part as a boundary line, as described above, and can dramatically increase the number of types of effect waveforms.

[Brief explanation of drawings]

Fig. 1 is a configuration explanatory diagram showing the subsidiary video special effect signal generating device, Fig. 2 a to c are waveform diagrams shown to explain the operation of Fig. Figures 4a to 4c are waveform diagrams in which the horizontal and vertical waveform ratios of the waveform in Figure 2a are different, and Figures 5 and 6 are diagrams shown to explain an example of the wipe pattern obtained on the television screen. A diagram shown to explain the rotational change of the wipe boundary line when the slice level Ls of the waveform shown in FIG. 4 is constant and when it changes, and FIG. Figures 8a to 8e are diagrams showing waveform changes of the synthesized fundamental wave necessary to obtain the rotational changes of the wipe boundary line in Figure 7, and Figures 9 and 10 are diagrams showing examples of the wipe boundary line in Figure 8. The first diagram is shown to explain the rotational change of the wipe boundary line when the slice level of the waveform is constant and when it changes.
Figures 1 and 12 are other examples of wipe patterns on a TV screen obtained by the operation shown in Figure 1, showing cases in which the center of rotation is constant and cases in which the center of rotation changes, and Figure 13 shows the conventional wipe pattern. FIGS. 14a to 14f are explanatory diagrams illustrating the configuration of an embodiment of a video special effect signal generating device according to the first embodiment.
Waveform diagram No. 15 shown to explain the operation of the device shown in FIG.
The figure is a circuit diagram showing an example of the reference level insertion circuit of FIG. 13, and FIG. 16 is a diagram shown to explain the relationship between the horizontal and vertical fundamental waves of FIG. 14 and the wipe pattern on the television screen.
17 to 20 are diagrams shown to explain the relationship between the horizontal and vertical fundamental waves and the wipe pattern on the television screen in other operational examples of the device shown in FIG. 13, and FIG. A configuration explanatory diagram showing an example of another video special effect signal generation device, FIGS. 22a to 22e are waveform diagrams shown to explain the operation of the device in FIG. 21, and FIG. 23 is a horizontal and vertical diagram of the device shown in FIG. Figures 24 to 26 are diagrams for explaining the relationship between the fundamental wave and the wipe pattern on the TV screen, and the horizontal and vertical fundamental waves and the wipe pattern on the TV screen in other operation examples of the device shown in Figure 21 are shown. FIG. 27 is a configuration explanatory diagram showing a part of a modification of FIG. 1, and FIG. 28 is a configuration showing an embodiment of the video special effect signal generation device according to the present invention. Explanatory drawings, Figures 29 a to d
28 is a diagram showing the wave pattern obtained from FIG. 28 together with signal conditions, FIG. 30 is a configuration explanatory diagram showing the logic synthesis circuit of FIG. 28, and FIGS.
It is a figure which shows the different example of the wipe pattern obtained from a figure. 1, 2... Fundamental wave generation circuit, 3, 4... Level adjuster, 5... Mixing circuit, 6, 23, 24
... Slice circuit, 10, 21, 22 ... Clamp circuit, 11, 12 ... Reference level insertion circuit, 13, 14 ... Polarity inversion circuit, 17, 18 ... Switch, 25 ...Logic synthesis circuit. Figure 1 Figure 2 Figure 3 Figure 5 Figure 6 Figure 7 Figure 4 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 Figure 16 Figure 17 Figure 18Figure 19Figure 20Figure 21Figure 22Figure 27Figure 28Figure 30Figure 31Figure 32Figure 33Figure 23Figure 24Figure 25Figure 26Figure 29

Claims (1)

[Claims] 1. In a video special effect signal generation device that generates a key signal for controlling the switching and selection of two types of video signals to generate a rotating wipe pattern on a television screen, horizontal and vertical signals with a predetermined section set to a reference level are used. fundamental wave generating means for respectively generating a horizontal fundamental wave signal and a vertical fundamental wave signal having a period of a level control means for controlling increase/decrease across the range, a mixing means for mixing the horizontal fundamental wave signal and the vertical fundamental wave signal whose amplitude and polarity are controlled by the means to obtain a mixed fundamental wave signal, and a mixed fundamental wave signal obtained by the means. key signal generating means for generating a rotation wipe key signal by clamping the wave signal at a predetermined clamp level for a reference level setting section of each fundamental wave signal and then slicing it at the same level as the clamp level; and the fundamental wave generating means. Each generated fundamental wave signal is separately clamped at a predetermined clamp level in a reference level setting interval, and the clamped horizontal fundamental wave signal or vertical fundamental wave signal is sliced at the same level as the above clamp level to obtain horizontal or vertical components. means for obtaining a gate signal; and a key signal corresponding to a rotational wipe in which a part of the wipe boundary line is fixed by combining the gate signal obtained by the means and the rotational wipe key signal obtained by the key signal generation means. What is claimed is: 1. A video special effect signal generating device, comprising means for generating a video special effect signal.