JP2002314949A - Signal conversion apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a signal converting apparatus for converting an image signal transmitted by a 1/60 non-interlaced signal into a 1/30 interlaced signal to output the signal. SOLUTION: In the signal conversion apparatus for converting the image signal picked up by a 1/60 non-interlaced camera into the 1/30 interlaced signal to output the signal, the image signals to be inputted are written in an FIFO type memory by switching between the image signals consisting of only scanning lines in odd-ordered rows and the image signals consisting of only the scanning lines in even-ordered lines, the written image signals are outputted at prescribed intervals in a time 2T two times a writing interval T. By doing this, the image signals for one frame transmitted by the 1/30 interlaced signal can be outputted by the image signals for two frames transmitted by the 1/60 non-interlaced signal, thereby converting the image signal transmitted by the 1/60 non-interlaced signal into the image signal transmitted by the 1/30 interlaced signal with a simple structure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal converter for converting an image signal input as a 1/60 non-interlace signal into a 1/30 interlace signal and outputting the converted signal.

[0002]

2. Description of the Related Art NTSC monitor devices are widely used as display monitors for displaying color images.
In the monitor device of this system, 1 /
A 30 interlace signal is used, and 30 frames are displayed per second. Each frame is obtained by superimposing an odd field and an even field, which are created by individually performing interlaced scanning of odd rows and even rows of the scanning lines, on one screen.

In recent years, 1/60 non-interlaced cameras have been used as imaging devices.
In this imaging method, 60 images are output per second by continuously scanning each scanning line without performing interlaced scanning such as an interlace signal at the time of image resolution scanning.
As a result, there is an advantage that the image output speed can be increased and a high-definition image can be captured for a moving image.

[0004]

However, in order to display an image acquired by a 1/60 non-interlaced camera, a dedicated display device corresponding to a 1/60 non-interlaced signal is required. At present, this dedicated device is expensive and is not widely used.
0 There is a disadvantage that image data captured by a non-interlaced camera cannot be easily displayed.

Accordingly, an object of the present invention is to provide a signal converter capable of converting an image signal transmitted as a 1/60 non-interlaced signal into a 1/30 interlaced signal and outputting it with a simple configuration. And

[0006]

According to a first aspect of the present invention, there is provided a signal converter for converting an image signal input as a 1/60 non-interlace signal into a 1/30 interlace signal and outputting the converted signal. Storage means for selectively storing image signals corresponding to only odd-numbered rows or only even-numbered rows of scanning lines among image signals input as the 1/60 non-interlaced signal; Every time the frame is switched, the storage of the image signal corresponding to each scanning line stored by the storage unit is switched from storage of only odd rows to storage of even rows or storage of only even rows to storage of only odd rows, By periodically outputting the stored image signal over twice the time required for storage, 1 /
Control means for converting the signals into 30 interlaced signals.

According to a second aspect of the present invention, there is provided a signal conversion apparatus.
The signal conversion device according to any one of the preceding claims, wherein the image signal for two frames transmitted as a 1/60 non-interlaced signal is
An image signal for one frame transmitted as a 1/30 interlace signal is output.

According to the present invention, of image signals transmitted as 1/60 non-interlaced signals, image signals corresponding to only odd-numbered rows or only even-numbered rows of scanning lines are selectively stored, and Every time the frame of the 60 non-interlaced signal is switched, the storage of the image signal is switched from the storage of only the odd-numbered rows to the storage of only the even-numbered rows or from the storage of only the even-numbered rows to the storage of only the odd-numbered rows, and stores the stored image signals The image signal transmitted as a 1/60 non-interlaced signal can be converted into a 1/30 interlaced signal with a simple configuration by periodically outputting the signal by taking twice as long as the time required for (1). .

[0009]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a signal conversion device according to one embodiment of the present invention, FIG. 2 is a timing chart showing image signal conversion processing by the signal conversion device according to one embodiment of the present invention, and FIG. FIG. 4 is an explanatory diagram of a scanning order in a / 60 non-interlaced signal, and FIG. 4 is an explanatory diagram of a scanning order in a 1/30 interlaced signal.

First, the configuration of the signal conversion device will be described with reference to FIG. In FIG. 1, an image conversion unit 1 is connected to an imaging device 2 and a display device 3. The imaging device 2 is 1/60
It is a non-interlaced camera, and an image signal obtained by imaging is output as a 1/60 non-interlaced signal. The display device 3 is the most commonly used NTS
It is a display monitor of the C system, and displays an image by an image signal of a 1/30 interlace signal. The signal conversion unit 1
It has a function of converting an image signal transmitted as a 1/60 non-interlaced signal into a 1/30 interlaced signal.

The signal conversion unit 1 includes a FIFO type (first-in first-out) memory 6 and a control unit 8. The image signal output from the imaging device 2 is converted into a digital signal by the A / D conversion unit 5. Later, the FIFO type memory 6 (hereinafter, referred to as FIFO type memory 6)
(Hereinafter simply referred to as “memory 6”), sequentially read out, converted into an analog signal by the D / A converter 7, and then output to the display device 3.

The control unit 8 includes a timing control unit 9, a WRI
A TE signal generation circuit 10, a reset circuit 11, and a READ signal generation circuit 12 are provided. The timing control unit 9
WRITE signal generation circuit 10, reset circuit 11, RE
A predetermined timing signal is output to the AD signal generation circuit 12. The WRITE signal creation circuit 10 creates a WRITE signal according to the timing signal, and outputs it to the memory 6. The WRITE signal is a control signal for controlling writing of the input signal converted into the digital signal by the A / D converter 5 into the memory 6.

A READ signal generating circuit 12 generates a READ signal in accordance with the timing signal, and
Output to The READ signal is a control signal for controlling reading of the image signal written in the memory 6.
The reset circuit 11 resets a write counter and a read counter for the memory 6 according to the timing signal.

The signal conversion section 1 is connected to the image processing section 4, and the image signal converted by the A / D conversion section 5 can be transferred to the image processing section 4. This gives 1
Various image processing can be performed on image data obtained by a / 60 non-interlaced camera.

The synchronizing signal generating circuit 13 generates a horizontal and vertical synchronizing signal for a 1/30 interlaced image. The synchronizing signal is superimposed on the 1/30 interlaced signal and transmitted to the display device 3. Is done.

Next, with reference to FIGS. 2, 3, and 4, a signal conversion process of an image signal will be described. FIG. 2 shows the timing of a signal conversion process in which the input signal converted into a digital signal is written to the memory 6 and the written image signal is read out and output as a predetermined output signal. FIGS. 2 (a) and 2 (b) show an example of an image signal transmitted for display monitor of the NTSC system, in which 52
The figure shows signal conversion processing at the time of outputting as an odd field and outputting as an even field, which output only image signals corresponding to the scanning lines of the odd and even rows, respectively, of the five scanning lines.

In an image signal obtained by the image pickup apparatus 2 having a 1/60 non-interlaced camera, one screen (one frame FR) is 525 as shown in FIG.
It is constituted by the scanning lines L. In the image decomposition scanning and the image assembling scanning, for one frame,
525 horizontal scans are performed. At this time, each scanning line L is sequentially scanned without performing the interlaced scanning, and one scanning is performed in 1/60 second.
An image signal for a frame is transferred. Therefore, the image signal transfer interval T per scanning line L is
(1/60) ÷ 525 seconds.

The image signal transmitted for each scanning line at the interval T is transmitted to the image conversion unit 1 as an input signal. That is, the interval T of the input signal shown in FIGS. 2A and 2B is equal to the interval T. Here, for each input signal, the input signal for one scanning line L is set to the Nth (N is an arbitrary odd number), and N + 1,
Are assigned in the order of N + 2, N + 3,... To distinguish continuous input signals.

At the time of output as an odd field, FIG.
As shown in (a), the WRITE signal is output from the WRITE signal generation circuit 10 to the memory 6 only when the input signals N, N + 2... Corresponding to the odd-numbered scanning lines are input. . As a result, of the input signals sequentially input, only the input signals corresponding to the odd-numbered scanning lines are selectively written into the memory 6.

When reading an image signal, an input signal of a number corresponding to an odd-numbered scanning line written in the memory 6 is input to the RE signal output from the READ signal generation circuit 12.
It is read for each scanning line according to the AD signal. Here, the READ signal that determines the read time is output over a time 2T that is twice the interval T of the input signal. That is, the output signal is output in twice the time required for writing the input signal. As a result, as shown in FIG. 4A, only the odd-numbered scanning lines LO, which skip over the even-numbered scanning lines LE one by one, are formed.
An odd field FO by the 1/30 interlace signal is obtained.

At the time of output as an even-numbered field, as shown in FIG. 2B, the WRITE signal is output only at the timing when the input signals N + 1, N + 3... The WRITE signal is output from the WRITE signal generation circuit 10 to the memory 6. This allows
Only the input signals of the numbers corresponding to the even-numbered scanning lines among the input signals sequentially input are selectively written to the memory 6. When reading the image signal, the input signal of the number corresponding to the even-numbered scanning line written in the memory 6 is read by the READ signal output from the READ signal generation circuit 12.
It is read out for each scanning line according to the signal. At this time, similarly, the READ signal is output at the interval T of the input signal 2
The output is performed over 2T times. As a result, FIG.
As shown in (b), the odd-numbered scanning lines LO are skipped one by one, and are composed of only the even-numbered scanning lines LE.
An even field FE by the / 30 interlace signal is obtained.

Therefore, in the above configuration, the memory 6
Are storage means for selectively storing image signals corresponding to only odd-numbered rows or only even-numbered rows of a scanning line among image signals input as 1/60 non-interlaced signals.

In this signal conversion processing performed via the memory 6, one frame FR transmitted as a 1/60 non-interlaced signal shown in FIG. 3 is output at the time of output as an odd field and at the time of output as an even field. , And an even field FE is output from the next frame FR.

An image signal for one frame transmitted as a 1/30 interlace signal is output by two fields of the odd field FO and the even field FE. That is, in the above-described signal conversion processing, an image signal for one frame transmitted as a 1/30 interlace signal is output based on an image signal for two frames transmitted as a 1/60 non-interlace signal.

In the above-described signal conversion process for two frames, the control unit 8 changes the input signal to be written into the memory 6 every time the 1/60 non-interlace signal frame is switched, in the odd row. From writing of input signals corresponding to only scanning lines to writing of input signals corresponding to only even-numbered scanning lines, or writing of input signals corresponding to only even-numbered scanning lines, corresponding to only odd-numbered scanning lines Switch to writing of input signal. When reading out the written image signal, the image signal is periodically output with a reading time twice as long as the writing time set equal to the input interval T. As a result, an image signal transmitted as a 1/60 non-interlace signal is converted into a 1/30 interlace signal.

That is, every time the frame of the 1/60 non-interlace signal is switched, the control unit 8 changes the storage of the image signal corresponding to each scanning line stored in the storage means from the storage of only the odd rows to the storage of the even rows. Switching from storage or storage of only even-numbered rows to storage of only odd-numbered rows, and converting the stored image signal to a 1/30 interlace signal by periodically outputting the stored image signal over twice the time required for storage. It is a control means.

As described above, by using the signal conversion device having the above configuration, an image captured by a 1/60 non-interlaced camera is generally used without using an expensive dedicated display device. It can be easily displayed on an NTSC display monitor.

[0028]

According to the present invention, of image signals transmitted as 1/60 non-interlaced signals, image signals corresponding to only odd-numbered rows or only even-numbered rows of scanning lines are selectively stored, Every time the 1/60 non-interlace signal frame is switched, the storage of the image signal is switched from storage of only odd rows to storage of even rows or storage of only even rows to storage of only odd rows. Is output periodically by taking twice as long as the time required for storage, so that the image signal transmitted as a 1/60 non-interlaced signal can be converted into a 1/30 interlaced signal with a simple configuration. And an image acquired by a 1/60 non-interlaced camera can be displayed on an NTSC display monitor.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a signal conversion device according to an embodiment of the present invention.

FIG. 2 is a timing chart showing image signal conversion processing by the signal conversion device according to one embodiment of the present invention;

FIG. 3 is an explanatory diagram of a scanning order in a 1/60 non-interlaced signal.

FIG. 4 is an explanatory diagram of a scanning order in a 1/30 interlace signal.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 signal conversion device 2 imaging device 3 display device 6 memory 8 control unit 10 WRITE signal generation circuit 12 READ signal generation circuit FR frame L scanning line

Claims (2)

[Claims] 1. A signal conversion device for converting an image signal input as a 1/60 non-interlace signal into a 1/30 interlace signal and outputting the converted signal, wherein the input signal is input as the 1/60 non-interlace signal. Storage means for selectively storing image signals corresponding to only the odd-numbered rows or even-numbered rows of the image signal; and each of the storage means for storing the 1/60 non-interlaced signal every time a frame is switched. The storage of the image signal corresponding to the scanning line is switched from the storage of only the odd-numbered rows to the storage of only the even-numbered rows or from the storage of only the even-numbered rows to the storage of only the odd-numbered rows, and is twice the time required for storing the stored image signals. Control means for converting the signal into a 1/30 interlace signal by periodically outputting the signal over time. 2. An image signal for one frame transmitted as a 1/30 interlace signal is output from an image signal for two frames transmitted as a 1/60 non-interlace signal. 2. The signal conversion device according to 1.