JPH0537854A - Digital video special effect device - Google Patents

Abstract

PURPOSE:To provide the digital video special effect device in which a special effect giving an offset to a video image is obtained based on an optional angular direction. CONSTITUTION:A distance d=aX+bY+c between a point (X,Y) and a straight line aX+bY+c=0 is obtained by addresses X,Y and constants a,b,c given in response to a desired effect by a read address modification section. X and Y offsets obtained by multiplying b'=costheta and a=sintheta with an output of a function generating section 2 outputting a function in response to the distance (d) are added respectively to the addresses X,Y. Thus, the offset effect to a video image is given with respect to an optional angle direction by varying theta,c..

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital video special effect device for processing a digitized video signal in real time.

[0002]

2. Description of the Related Art FIG. 2 is a block diagram showing an example of a conventional digital video special effect device. A conventional digital video special effect device includes an input processing unit 12 to which a video signal is applied via an input terminal 11, a video memory 13 for storing video data, a write address generating unit 16 for generating a write address, an effect control unit 20, It is composed of a read address generator 17 for generating a read address based on the output of the effect controller 20, and an output processor 14 for processing the data output from the video memory 13 and outputting it to the output terminal 15. The read address generation unit 17 also includes a basic read address generation unit 19 and a read address modification unit 18.

The video signal is given to the input processing section 12 via the input terminal 11. The input processing unit 12 performs PCM digitization of analog signals and separation of luminance signals and chrominance signals. The video data digitized by the input processing unit 12 is stored in the video memory 13 based on the addresses sequentially generated by the write address generation unit 16 in synchronization with the input video.
Written in. The video data written in the video memory 13 is read based on a read address described later,
The output processing unit 14 performs synthesis with the background image signal, synthesis with the luminance signal and color signal, etc., and outputs as a video signal.

In general, the special effect is realized by the read address generator 17 generating read addresses in a different order from the write addresses. That is, in FIG. 2, if the output of the basic read address generator 19 that generates a sequential address similar to the write address is used as it is as the read address of the video memory 13, the output video becomes the same as the input video, but the read address is modified. By changing the read address using the unit 18, an output video different from the input video can be obtained. The effect control unit 20 outputs a signal that determines the operation of the read address modification unit 18.

FIG. 3 is a block diagram showing an example of the address modification unit 18.

In FIG. 3, X _i and Y _i are two-dimensional addresses of the video memory 13 and are output from the basic read address generating section 19 (or the basic read address generating section 1).
9 is the result of modifying the output of 9 by a predetermined effect generation method). Further, X ₀ and Y ₀ are outputs of this address modification unit. Further, K is a constant given by the effect control unit 20, and is a value in the range of 0 to 1.

The function generator 24 is an arithmetic circuit that generates a function value f (Y _i ) for changing the X address in response to a change in the Y address, and generates a function value according to the intended effect. It is a thing. The multiplier 21 multiplies the output of the function generator 24 and the constant K given from the effect controller 20. The adder 22 gives an offset to the X address (horizontal direction) by adding the output of the multiplier 21 to the address X _i .

For example, the address of the video memory 13 is shown in FIG.
, That is, an image in a rectangular range in which an address in the X direction is in the range from −h to h and an address in the Y direction is in the range from −v to v,
The function generator 24 is assumed to generate a function value (s is a constant) such that f (Y _i ) = s × Y _i . Then, an offset proportional to the value of the address Y _i is given to the address X _i , and the output image becomes a diagonally shifted image as shown in FIG.

In this case, if K = 0, the offset amount becomes 0, and the same image as the input image is output. If K = 1, the maximum offset amount defined by the function f (Y _i ) is given.

In this way, the offset amount can be adjusted. Further, by replacing X and Y in FIG. 3, it is possible to change the shift direction due to the offset from the horizontal direction to the vertical direction.

As another modification, the function generator 24 uses f
(Y _i ) = {mod ([Y _i / m], 2) × 2-1} × s
Suppose that a function value of However, mod (p, q) represents the remainder obtained by dividing p by q, and [r] represents the integer part of r. Then, the address X _i is the address Y _i is m
The offset is given in the horizontal direction alternately by s each time. As a result, the output image becomes an image which is alternately shifted by a predetermined width as shown in FIG.

[0012]

However, in the conventional digital image special effect device, it is possible to generate a special effect in which an input image is offset in either the horizontal direction or the vertical direction. In Although,
There is a problem that it is not possible to give a tilted offset. For example, it is not possible to obtain an image that is shifted in an oblique direction as shown in FIG. 7 or an image that is inclined as shown in FIG. For this reason, the conventional image special effect device has a drawback that the change as a special effect is scarce and the user is easily bored.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a digital image special effect device capable of obtaining an image to which an offset is simultaneously applied in the horizontal direction and the vertical direction. And

[0014]

A digital video special effect device according to the present invention writes video data obtained by digitizing an input video signal to a video memory based on a write address, and writes the written video data at the time of writing. In a digital video special effect device that reads out based on different read addresses and outputs as a video signal, a distance calculation unit that calculates a distance between a position designated by the X address and Y address of the read address and a predetermined straight line, A function generator that outputs a function value based on the calculation result of the distance calculator,
First multiplying means for multiplying a value given by the function generating section by a first constant; first adding means for adding the output of the first multiplying means to the X address; and the function generating section. And a second addition means for adding the output of the second multiplication means to the Y address.

[0015]

In the present invention, the distance calculation unit for calculating the distance between the position designated by the X address and Y address of the read address and an arbitrary straight line is provided, and the function generation unit calculates by this distance calculation unit. Generate a function value based on the result. The first multiplication means multiplies the value given by the function generating section by the first constant, and the first addition means adds the output of the first multiplication means to the X address. On the other hand, the second multiplying means multiplies the value given from the function generating section by the second constant, and the second adding means adds the output of the second multiplying means to the Y address. As a result, offsets can be applied to both the X address and the Y address at the same time, and it becomes possible to realize various special effects not possible with the conventional digital video special effect device.

Incidentally, the distance calculation circuit is, for example, the address X.
And a second constant, the third multiplication means for multiplying the second constant with the fourth constant, the fourth multiplication means for multiplying the address Y with the third constant, and the outputs of the third and fourth multiplication means and the fourth constant. It can be configured by a third adding means for adding.

Further, instead of directly giving the output of the function generating section to the first and second multiplying means, there is provided an effect amount multiplying means for multiplying the output of the function generating section by a fifth constant,
The first and second multiplication means may multiply the output of the effect amount multiplication means by the first constant and the second constant. Thereby, the effect amount can be changed by changing the fifth constant.

[0018]

Embodiments of the present invention will now be described with reference to the accompanying drawings.

FIG. 1 is a block diagram showing a read address modification unit of a digital video special effect device according to an embodiment of the present invention. The present embodiment is different from the conventional one in that the configuration of the read address modification unit is different, and other configurations are basically the same as the conventional one.

In FIG. 1, X _i and Y _i are two-dimensional addresses of the video memory, which are outputs of the basic read address generator (or the result of modification thereof). Also, X ₀
And Y ₀ are the outputs of the address modifier.

The apparatus according to the present embodiment comprises a distance calculation unit 1, a function generation unit 2 for generating a predetermined function based on the output of the distance calculation unit 1, and an effect amount adjustment for multiplying the output of the function generation unit 2 by a constant K. Multiplier 3 for calculating the offset amount of the X address (horizontal direction) for multiplying the output of the multiplier 3 by the constant b ′, and the Y address for multiplying the output of the multiplier 3 by the constant a (vertical Direction) offset amount multiplier 5, X
It is composed of an address offset adder 6 and a Y address offset adder 7.

The distance calculation unit 1 adds a multiplier 1a for multiplying the address X and the constant a, a multiplier 1d for multiplying the address Y and the constant b, and an adder for adding the output of the multiplier 1a and the constant c. And an adder 1c for adding the output of the adder 1b and the output of the multiplier 1d. Therefore, this distance calculation unit 1 is d = a × X _i + b × Y _i + c
To perform the operation. The constants a, b, b ', and c are all given by the effect controller.

Where a = sin θ, b = −cos θ,
If b ′ = − b and c = − (X ₀ sin θ−Y ₀ cos θ), d passes through the point (X ₀ , Y ₀ ) and has a slope t.
It represents the distance from a straight line that is an θ and an arbitrary point (X _i , Y _i ). That is, the distance calculation unit 1 is a calculation circuit that calculates the distance from the pixel address indicated by the input address to an arbitrary straight line.

The function generator 2 obtains the maximum offset required for the distance between the point calculated by the distance calculator 1 and the straight line when the coefficient to the effect amount adjusting multiplier described later is 1. To determine the function value. The function generating section 2 may be composed of only an arithmetic circuit, or may be composed of a storage element in which a previously calculated function value is written. According to the latter method, even if a function value is a complicated operation and the operation is not completed within the required processing time, it is possible to read the function value from the storage element in which the result is written in an extremely short time. Therefore, there is an advantage that the function value can be set freely.

The multiplier 3 limits the effect by a constant K (where 0≤K≤1) given from the effect control section. K
When = 0, the offset amount is 0 for both X and Y,
When K = 1, the maximum offset determined by the function generator 2 is given.

The multipliers 4 and 5 for calculating the offset amounts of the X address and the Y address multiply the output offset values of the function generating section 2 by cos θ and sin θ, respectively, to obtain a straight line aX _i +.
The component in the direction of bY _i + c = 0 is obtained. Then, the offset amount adders 6 and 7 add the calculated offset amounts of the X and Y components to the input X address and Y address, respectively,
An address X ₀ and an address Y ₀ are generated.

As an example of the function generator 2, if the address of the video memory is defined as shown in FIG.
Assuming that a function value (d) = s × d (s is a constant) is given, X _i receives an offset proportional to the value of d, and the output image appears to be slanted as shown in FIG. It becomes a picture.

As another example, f (d) = {mod ([d
/ M], 2) × 2-1} × s
_i is offset horizontally by s every time d changes by m. Therefore, the output image becomes an inclined image as shown in FIG.

[0029]

As described above, in the present invention,
A distance calculation unit that calculates a distance between a position designated by the X and Y addresses of the read address and an arbitrary straight line by the distance calculation unit; and a function generation unit that generates a function value based on the calculation result of this distance calculation unit. The output of the function generator or the result of multiplying the function generator by the fifth constant is multiplied by the first constant and the second constant, and the result is added to the X address and the Y address. Therefore, the offset can be applied in the horizontal direction and the vertical direction at the same time. As a result, it is possible to obtain a special effect such as an image which is alternately shifted in an oblique direction, which has been impossible in the past.

[Brief description of drawings]

FIG. 1 is a block diagram illustrating a read address modification unit of a digital image special effect device according to an exemplary embodiment of the present invention.

FIG. 2 is a block diagram showing an example of a conventional digital image special effect device.

FIG. 3 is a block diagram showing an example of the address modification unit of the same.

FIG. 4 is a schematic diagram showing addresses of a video memory.

FIG. 5 is a schematic diagram showing an example of an output image by a conventional digital special effect device.

FIG. 6 is a schematic diagram showing another example of an output image by a conventional digital special effect device.

FIG. 7 is a schematic diagram showing an example of an output image that cannot be output by a conventional digital special effect device.

FIG. 8 is a schematic diagram showing another example of an output image that cannot be output by the conventional digital special effect device.

[Explanation of symbols]

1; Distance calculator 1a, 1d, 3, 4, 5, 21; multiplier 1b, 1c, 6, 7, 22; adder 2, 24; function generator 12: Input processing unit 13; video memory 14: Output processing unit 16; write address generation unit 17: Read address generator 20; Effect control unit

Claims (3)

[Claims] 1. A digital circuit for writing video data obtained by digitizing an input video signal to a video memory based on a write address, reading the written video data based on a read address different from that at the time of writing, and outputting the read video data as a video signal. In the video special effect device, the X of the read address is
A distance calculation unit that calculates a distance between a position designated by an address and a Y address and a predetermined straight line, a function generation unit that outputs a function value based on a calculation result of this distance calculation unit, and a function generation unit First multiplication means for multiplying a value by a first constant, first addition means for adding an output of the first multiplication means to the X address, and a value given from the function generator A digital video special effect device comprising: a second multiplication means for multiplying a constant of 2; and a second addition means for adding the output of the second multiplication means to the Y address. 2. The distance calculating section comprises third multiplying means for multiplying the X address by the second constant, and fourth multiplying means for multiplying the Y address by a third constant. 2. The digital video special effect device according to claim 1, wherein the digital video special effect device is constituted by a third adding means for adding the calculation results of the third and fourth multiplying means and a fourth constant. 3. An effect amount multiplying means for multiplying an output value of the function generating section by a fifth constant is provided, and the first and second multiplying means are provided with the effect amount multiplier to obtain the effect amount multiplying means. 2. The output value of the function generator is given.
Alternatively, the digital video special effect device according to item 2.