JPH0831984B2 - Video effect device - Google Patents

Description

Description: TECHNICAL FIELD The present invention particularly uses two line memories to achieve a special video effect for a video signal having a horizontal sync signal and a vertical sync signal. Regarding the device.

[Conventional technology]

As is well known, the video effect device is generally used in broadcasting stations and the like, and as an effect that can be realized by this device, for example, to remove an image on one screen,
There are things that move like sweeping to the left and right, a so-called "page-turning effect" that gradually shrinks to the right of the screen without sweeping, and things that do this in the center of the screen, etc.
Various things are possible. Further, if a vertical effect is added, a so-called "superimpose" in which another screen is inserted in one corner of the screen can be considered.

Conventionally, a frame memory has been used to obtain such an effect. However, this method is not only large in capacity but also extremely complicated in terms of software and expensive in price, and is simple and easy for consumer use mainly for household use. There is a problem that it is not suitable as a video effect device aiming for an effect.

〔Purpose〕

The present invention has been made in view of the above problems, and does not use a frame memory unlike the conventional example.
It is an object of the present invention to provide a simple video effect device capable of performing various special effects only by using a memory for lines.

〔Example〕

The present invention will be described below with reference to the drawings. Figure 1 shows
1 is a block circuit diagram of an embodiment of a video effect device according to the present invention. In this embodiment, the analog CCD memories 18 and 19 are used as the line memory, and the effect of sweeping the screen rightward is obtained.

1 is an analog video signal input terminal, 26 is a start terminal, and the analog video signal input from the terminal 1 is
In the normal mode where no effect operation is performed,
By setting the start signal from the terminal 26 to "L" (low level), the output of the AND circuit 13 is set to "L" so that the switching circuits 14 and 21 are connected to the terminals E ₁ and F ₁ , respectively. To do.

On the other hand, the start signal for video effect operation is sent to terminal 26.
When input as "H" (high level) from, the Q output of the RS (reset and set) flip-flop circuit 5 changes from "L" to "H", which is the signal A and the AND circuit 13
The other output of the AND circuit 13 changes from "L" to "H", and this "H" is held until the flip-flop 5 is reset. As a result, the switching circuits 14 and 21 are switched to the terminals E ₂ and F ₂ , respectively, and writing / reading to / from the line memory is enabled.

An effect start signal is input to the counter 6 as a reset signal. Further, a clock obtained by dividing the vertical synchronizing signal V _D is input as the clock CK input.
Reference numeral 7 is a frequency dividing circuit for dividing the vertical synchronizing signal input to the terminal 27, which outputs a pulse once every n frames (2n vertical scanning period) with a frequency dividing rate of 1 / (2n). Is. By varying n here, the time required for the effect can be freely changed. This counter 6 is reset to be preset to the same value as a fixed preset value set in the subtraction counter 10 described later, and the count value of the divided vertical synchronizing signal counted in the counter 6 is preset in the subtraction counter 3. It is output as a value.

On the other hand, the video signal input to the terminal 1 is introduced into the sync signal separation circuit 22, and the next pulse shaping circuit 23 forms a pulse corresponding to the horizontal sync signal.

The subtraction counter 3 is reset by the horizontal synchronizing pulse obtained by the pulse shaping circuit 23 and preset to the count value output from the counter 6 as described above. Moreover, the the subtraction counter 3 as a clock input CK, short clock signal CK of period than the horizontal synchronizing pulses H _D start the leading edge and is matched the horizontal sync pulse H _D is supplied. Further, when the internal value of the counter 3 becomes 0, CA (carry-out) is issued, the carry-out output, together with the horizontal sync pulses H _D obtained from the pulse shaping circuit 23, respectively R · S
It serves as a set / reset input signal for the flip-flop circuit 8. From the Q output of the flip-flop circuit 8,
A control signal that becomes "H" is obtained when a certain time has elapsed from the leading edge of the horizontal sync pulse (timing at which the display of the effective screen starts). This output is the clock signal
It is input to the AND circuit 9 together with CK, from which a pulse signal for obtaining a clock pulse only during a predetermined screen projection period, that is, a pulse for reading the line memory is obtained. The timing of starting the screen projection is gradually delayed in time from the leading edge of the horizontal synchronizing pulse according to the count number of the counter 6. The output of the AND circuit 9 is connected to the terminals A ₁ and B ₁ of the switching circuits 15 and 16. The RC constitutes a read control means for changing the read state of the line memory in this way.

On the other hand, the horizontal synchronizing signal H _D made by the pulse shaping circuit 23, also supplied as a preset signal of the subtraction circuit 10, this presetting operation, the same value as the preset value of the counter 6 as described above It is preset.
Here, this value is a value corresponding to the time from the leading edge of the horizontal synchronizing pulse to the start of the effective screen. This preset value is fixed for 2n vertical scanning period,
The counter 3 decrements the internal count value by 1 from the preset value by counting down the input clock CK, and when the internal count value becomes 0, the carry-out output CA is output, which is the same as the RS flip-flop circuit 8 described above. , R ・ S
It is input to the set input terminal of the flip-flop circuit 11.
On the other hand, the horizontal synchronizing pulse is input to the reset input terminal of the flip-flop circuit 8, and this Q output is the AND circuit 9
Similarly, the clock pulse CK is supplied to the AND circuit 12.

In this case, since the subtraction counter 10 is always preset with a fixed preset value, the pulse signal e thus obtained is constantly clocked in the effective horizontal scanning period regardless of the count number of the vertical synchronizing pulse V _D. And is used as a write pulse for the CCD line memories 18 and 19. The output of the AND circuit 12 is the terminal of the switching circuits 15 and 16.
Connected to A ₂ and B ₂ , respectively.

The output of the switching circuit 15 is supplied to the analog CCD line memory 18 as the first line memory, and the output of the switching circuit 16 is supplied to the analog CCD line memory 19 as the second line memory.

24 is a switching control circuit as a control means, in response to the input horizontal sync pulses H _D, controls the writing and reading of the line memory alternately by controlling the switching circuit 15,16,17,20, for example, For odd lines, the connection side of the switching circuit is switched to terminals A ₁ , B ₂ , C ₂ , D ₁ , respectively, and for even line, the connection side is switched to terminals A ₂ , B ₁ , C ₁ , D ₂ , respectively. is there. That is, the CCD line memory to which the input clock signal is supplied to the CCD line memory to which the writing clock pulse which is the output of the AND circuit 12 is supplied and which is supplied to the reading clock pulse which is the output of the AND circuit 9 From the above, the output signal is supplied to the video signal output terminal 25.

In this embodiment, when the above video effect operation is completed, the original input video signal is switched again. That is, when the image projection period determined by the count value of the counter 6 becomes equal to 0, that is, when the count value of the counter 6 becomes equal to the number of pixels in one line,
This is detected by the arithmetic circuit 4 and the "H" signal is supplied to the reset input terminal R of the RS flip-flop circuit 5 to set the Q output to "L" and the AND circuit 13 output to "L". The switching circuits 14 and 21 are switched to the terminals E ₁ and F ₁ respectively.

FIG. 2 is a timing chart of each signal waveform in FIG. 1, and a to f correspond to a to f written in each line in FIG. The suffix N of f indicates that it corresponds to the Nth frame.

FIG. 3 is a diagram showing how the screen is swept to the right in this embodiment. According to the present embodiment, it is possible to obtain the effect of sweeping the screen rightward in this way.

〔effect〕

As described above with reference to the embodiments, according to the present invention, a video signal having a vertical synchronizing signal and a horizontal synchronizing signal is used without using a frame memory as in the conventional case.
With the memory for the lines, a simple video effect effect can be effectively obtained with a simple configuration.

[Brief description of drawings]

FIG. 1 is a block circuit diagram of an embodiment of a video effect device according to the present invention, FIG. 2 is a timing chart of each signal waveform in FIG. 1, and FIG. 3 is a diagram showing a video effect effect according to the present invention. Is. 1 …… Analog video signal input terminal 3,6 …… Counter 4,39 …… Computing circuit 14,15,16,17,20,21 …… Switching circuit 18,19 …… Analog CCD line memory 24 …… Switching control Circuit 25 …… Video signal output terminal 26 …… Start terminal

Claims (1)

[Claims] 1. Input means for inputting a video signal having a horizontal synchronizing signal and a vertical synchronizing signal, a plurality of line memories each storing a video signal for one horizontal scanning period, and the video signals in the plurality of line memories. Writing means for sequentially writing every one horizontal scanning period, reading means for sequentially reading the video signals stored in the plurality of line memories, mode designating means for designating an operation mode, and based on the horizontal synchronizing signal, And a control unit for switching the writing and reading operations in the plurality of line memories and controlling the operation timing of the reading unit based on the vertical synchronizing signal, the control unit according to the operation mode. The read start timing of the video signal for each horizontal scanning period for each signal is based on the vertical synchronization signal. Video effects apparatus, characterized in that the change had.