JPH07101927B2 - Image processing device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an image processing apparatus for obtaining a special effect reproduction image.

2. Description of the Related Art Conventionally, an image processing apparatus having a complicated structure has been required to provide a special effect, especially an afterimage effect, in a color image.

SUMMARY OF THE INVENTION Therefore, the present invention is to provide an image processing apparatus capable of obtaining an afterimage effect in a color image with a simple configuration.

The image processing apparatus of the present invention provides an A / D conversion means for digitizing an input composite video signal and a digital composite video signal of one field for every four fields of the digital composite video signal obtained from the A / D conversion means. First storage means for storing and repeatedly outputting the stored digital composite video signal over a 4-field period, and a field to be stored in the first storage means of the digital composite video signal obtained from the A / D conversion means. Of the digital composite video signal of 4n times (n is an integer of 2 or more), and the stored digital composite video signal is repeated over the period of the field of 4n times. The second storage means for outputting and the digital composite video signals output from the first and second storage means are combined to produce an analog composite video. It is characterized in that it comprises a D / A conversion means for converting and outputting to a signal.

EXAMPLES Examples of the present invention will be described below with reference to the drawings.

In the image processing apparatus as one embodiment of the present invention shown in the figure, a composite video signal is supplied to the A / D converter 1, and the composite video signal is, for example, an 8-bit digital signal by the A / D converter 1 at a predetermined timing. It is converted into a composite video signal. A / D
The output signal of the converter 1 is supplied to the first and second memories 2 and 3. Writing and reading of the first and second memories 2 and 3 are controlled by the memory control circuit 4. The first and second memories 2 and 3 have a storage position for one field of the digital composite video signal. First and second memories 2,
Each read digital composite video signal of 3 is added by the digital adder 5 and supplied to the D / A converter 6,
The output composite video signal of the converter 6 becomes the output signal of this device.

In such a configuration, the analog composite video signal is supplied to the A / D converter 1 and is A / D converted to the first and second memories.
Supplied to a few. The memory control circuit 4 generates a write command pulse for the first memory 2 at a predetermined timing only for one field period for every four fields in response to the horizontal and vertical synchronizing signals of the input composite video signal, and for the second memory 3. In order to write the same write field as the first memory 2 for every 16 fields, a write command pulse is generated at a predetermined timing for one field period. That is, the 1-field digital composite video signal of every 16 fields written in the second memory 3 is stored in the first memory 2
Write command pulses are individually generated from the memory control circuit 4 for the first and second memories 2 and 3 so as to be written into the memory control circuit 4.

The storage positions of the first and second memories 2 and 3 are changed and designated by an address counter (not shown) at a predetermined timing. In the first memory 2, the output digital composite video signal of the A / D converter 1 is written in one field out of every four fields in response to the write command pulse from the memory control circuit 4, and in the second memory 3 the A / D The output digital composite video signal of the converter 1 is written in only one field every 16 fields in response to a write command pulse from the memory control circuit 4. The digital composite video signal written in the second memory 3 for only one field out of every 16 fields is simultaneously written in the first memory 2. Further, the memory control circuit 4 generates a read pulse to the first and second memories 2 and 3 at a predetermined timing, and the contents of the storage position designated according to the output of the address counter are stored in the first and second memories 2 and 3. , 3 are read respectively. As a result, the 1-field digital composite video signal stored therein is read from the first memory 2 and the reading operation is repeated. In the first memory 2, one for every four fields as described above.
Since the digital composite video signal of only the field is written, the digital composite video signal of the same field is read from the first memory 2 over the four field period. On the other hand, the digital composite video signal for one field stored at that time is read from the second memory 3 in synchronization with the read timing of the first memory 2, and the reading operation is repeated. Since the digital composite video signal of only one field is written in the second memory 3 every 16 fields as described above, the digital composite video signal of the same field is read from the second memory 3 for the 16 field period. The digital composite video signals respectively read from the first and second memories 2 and 3 are combined by the adder 5, and the combined signal is D / A.
It is supplied to the converter 6.

The digital composite video signal read out from the first memory 2 is data of one field for every four fields of the input composite video signal as data that continues for four field periods, and an image that changes by fifteen fields per second is obtained. Can be considered. On the other hand, the digital composite video signal read from the second memory 3 becomes data in which the image of one field for every 16 fields of the input composite video signal continues for 16 field periods, and can be regarded as still image data.

By the way, the subcarrier frequency f _SC of the input composite video signal is NTS
In case of C method Can be expressed as Here, f _H is a horizontal synchronizing frequency and f _V is a vertical synchronizing frequency. That is, since the color signals are transmitted by the frequency interleaving method, the color signals of adjacent frames have opposite phases. Therefore, 4
Since the video signals of one field for each field have the same phase, so-called color fields coincide and they can be combined without adversely affecting the color signal components.

From this fact, the color fields of the moving image data output from the first memory 2 and the still image data output from the second memory 3 match, and even if these data are combined by the adder 5, the color fields also match. A normal color image can be obtained. Therefore, the D / A converter 6 outputs the analog composite video signal having the afterimage property, which is a combination of the moving image and the still image.

Incidentally, in the above-mentioned embodiment, the first and second memories
The digital video signals read out from 2, 3 are combined by an adder 5, and the digital signal obtained by the combination is D / A converted. The first and second memories 2,
The digital signals read from 3 may be D / A converted and then added.

Further, in the above-mentioned embodiment, the output video signal of the A / D converter 1 for every four fields is stored in the first storage means (memory 2), and the fields stored in the first storage means are stored. Fields having the same color phase are stored in the second storage means (memory 3) for every 16 fields of the output video signal of the A / D converter 1, but the present invention is not limited to this, and the first storage means stores 4 field units. 1 field of the digital video signal is sequentially stored at a cycle of 4 times, and 4n times (n is a value of 1 field of the digital video signal having the same color phase as the field stored in the first storage means in the second storage means). The data read from the first storage means is moving image data, and the data read from the second storage means is still image data by sequentially storing the data in a field unit cycle of an integer of 2 or more). It is sufficient if it can be used as a data. The second storage means does not necessarily need to store the video signal of one field at a constant cycle. For example, regarding the output video signal of the A / D converter 1, after storing the video signal of 1 field in the second storage means at a cycle of 16 fields, the video signal of 1 field is cycled at a cycle of 32 fields in the next cycle. You can remember it.

As described above, in the image processing apparatus of the present invention, the digital composite video signal of one field is stored in the first storage means for every four fields of the digital composite video signal obtained by digitizing the input composite video signal. The stored digital composite video signal is repeatedly output from the first storage means over a four-field period, and the digital composite video signal of the field to be stored in the first storage means out of the digitized digital composite video signals. Then, the digital composite video signal of one field for every 4n times field is stored in the second storage means, and the stored digital composite video signal is repeatedly output from the second storage means over the period of 4n times field, The digital composite video signals output from the first and second storage means are combined and the analog composite video signals are output. Since it is performed for converting a signal, a composite video signal is obtained having a residual image of a simple configuration. That is, for example, as in the embodiment, the output video signal of the A / D converter 1 for every 4 fields is stored in the first storage means, and the output video signal for the A / D converter 1 is stored for every 16 fields. When stored in the second storage means, the video signal read from the second storage means becomes a still image during the 16-field period, and it is read from the first storage means as a base of an afterimage. Since the thinned moving image by the video signal is combined with the screen, and the operation is updated with the new video signal and repeated, a visual afterimage effect is obtained.

[Brief description of drawings]

 The drawing is a circuit diagram showing an embodiment of the present invention. Description of main part code 1 …… A / D converter 2,3 …… Memory 4 …… Memory control circuit 5 …… Adder 6 …… D / A converter

Claims (1)

[Claims] 1. An A / D for digitizing an input composite video signal.
A converting means and a digital composite video signal of one field is stored for every four fields of the digital composite video signal obtained from the A / D converting means, and the stored digital composite video signal is repeatedly output over a four-field period. Of the digital composite video signals obtained from the first storage means and the A / D conversion means, the digital composite video signal of a field to be stored in the first storage means is 4n times (n is 2 or more). A second storage means for storing a digital composite video signal of one field for each (integer) field and repeatedly outputting the stored digital composite video signal over the period of the 4n times field; and the first and second storages. From the D / A conversion means for synthesizing the digital composite video signal output from the means and converting it to the analog composite video signal for output An image processing device characterized by the following.