JPS62256596A - High definition television signal system - Google Patents

Abstract

PURPOSE:To improve the resolution by thinning every other frame of 525 signals of 60 fields/60 frames/sec to convert them to 525 successive scan signals of 30 frames/30 fields/sec and subjecting them to signal processing. CONSTITUTION:In the image pickup transmission side, 525 successive scan signals of 30 fields/30 frames/sec have a high band component YH of a luminance signal Y subjected to two-dimensional amplitude modulation and have the frequency shifted into 4.2MHz transmission band and are multiplexed and are converted to 525 interlace NTSC-TV signals of 60 fields/30 frames/sec and are transmitted. In the reception side, they are converted to 525 successive scan video signals of 30 fields/30 frames/sec, and signals YL, C', and YH' are separated in a three-dimensional frequency area in case of a still picture and are separated in a two-dimensional frequency area in case of animation to demodulate them to signals Y, I, and Q, and they are converted to RBG signal and are converted to 525 successive scan video signals of 60 fields/60 frames/ sec and are projected. Thus, vertical and horizontal resolutions are considerably improved.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a high-definition television signal system, and more specifically, a high-definition television signal system that has full compatibility with the current NTSC system television signal [prior art] ] Conventionally, the Institute of Electronics and Communication Engineers Technical Report 0888-61 has been used as a high-definition television signal (hereinafter referred to as "TV double signal") system that is fully compatible with the NTSC television signal system.
There is a system described in ``Proposal of high-definition TV system with complete communication performance''. FIGS. 4(a) to 4(0) are diagrams showing an example of this method in a three-dimensional frequency domain. In this example, the high frequency component Ylf of the luminance signal (high definition information)
As shown by Ya' in FIGS. 4(a) and 4(c), the signal is frequency-converted and frequency-shifted within the transmission band of the current television signal, and the signal is multiplexed with the luminance signal and transmitted.

Further, as another TV signal system, there is a system described in the Technical Report of the Television Society of Japan ``On the TEnstos-4r EyeVision''. A diagram of the principle of this method is shown in FIG.

Imaging in the eye vision system is performed by sequential scanning of 525 lines and 30 fields/30 frames/sec. This signal is once written in the frame memory, and by reading it out in increments, it becomes an eye vision NTSC signal (525 lines, sequential scanning at 60 fields/30 frames/second).

This signal is configured to be compatible with conventional NTSC receivers. The iVision receiver is equipped with a 2-frame memory, and once the iVision NTSC signal is written for one frame, it is read out at twice the speed, and in the meantime, the signal for the next frame is written to the other frame memory, which is repeated. An image of 525 scanning lines and sequential scanning at 60 fields/60 frames/sec is displayed on a cathode ray tube.

[Problem that the invention seeks to solve]

In the former method, in the case of moving image input, in the three-dimensional frequency domain shown in Fig. 4, the luminance signal YL, high-definition information Y
The bands of the H and color signals C in the f-axis direction are widened, and unless the respective signals are band-limited, it is strictly impossible to separate them into each component on the receiving side. Therefore, there are problems such as deterioration of dynamic characteristics.

In addition, in the latter method, 525 lines, 30 fields/3
The vertical resolution is improved because it captures images with a sequential scan rate of 0 frames/second and displays images with 525 lines and 60 fields/60 frames/second sequential scans, but the horizontal resolution is the same as the current method. Improvement in horizontal resolution is desired.

This invention was made to solve the above problems, and whether the input signal is a still image or a moving image,
It is an object of the present invention to obtain a high-definition TV signal system that can improve both vertical resolution and horizontal resolution and has complete compatibility with the current NTSC TV signal system.

[Means for solving problems]

The high-definition TV signal system according to this invention has 52
5 lines/30 fields/30 frames/sec sequential scanning R
Convert the BG signal to a luminance signal Y, I signal and Q signal,
The high-frequency component Yn is extracted from the Y signal, and the vertical spatial frequency is 525/2 lines, the horizontal spatial frequency is 1/2 of the color subcarrier frequency fso or a frequency near it, and the temporal and spatial frequency is 15 Hz. Apply amplitude modulation,
Also ■.

The vertical spatial frequency of the color signal C converted from the Q signal is 525.
74 carrier waves with a temporal and spatial frequency of 15 Hz are subjected to two-dimensional amplitude modulation, and these modulated signals YH', O'
and the low frequency component YL of the luminance signal, and converts this multiplexed signal into an interlaced NTSC signal of 525 lines/60 fields/30 frames/sec.

Also, on the receiving side, the received NTSC signal is
It is converted into a sequential scanning signal of 5 lines/30 fields/30 frames/sec, and from this converted signal YL, O', YH
Separate and extract the 'signal in the three-dimensional frequency domain in the case of a still image, or in the two-dimensional frequency domain in the case of a moving image, and demodulate the Yn' signal and C'-fold signal, respectively. Then, the luminance signal Y is reproduced from the demodulated signal YH and the YL multiplied signal, and the 1 signal and C are reproduced from the demodulated color signal C.
Regenerate the signals, then convert these signals to 525 lines, 30 fields/30 frames/second progressively scanned video signals, and convert the signals to 525 lines, 60 fields/60 frames/second progressively scanned NTSC signal. .

[Effect]

In the high-definition TV signal system according to the present invention, on the transmitting side, a 525-line, 30-field/30-frame/sec sequentially scanned video signal is used as an original signal, and three-dimensional (vertical-horizontal one-hour) amplitude modulation is performed to increase the brightness. High frequency component of signal YH times signal 4.2
The frequency is shifted to a predetermined frequency range within the MHz transmission band, and the color signal C is two-dimensionally (vertically temporally) amplitude modulated to be frequency shifted to a predetermined frequency range, and each of these signals YL, YH' , O' is multiplexed to 525 lines, 30
A progressive scanning RBG signal of frames/30 fields/second is converted to an incremental NTSC signal of 525 lines and 60 fields/30 frames/second.

In addition, on the receiving side, the received signal is
This is converted into a sequential scanning signal of 30 fields/30 frames/second, and from this converted signal, YL, O, which is separated in a three-dimensional (horizontal-vertical hour) frequency domain when it is a still image, is obtained.
', Yll' signals, and in the case of moving images, two-dimensional (
(horizontal-vertical) YL, O', Y separated in the frequency domain
Takes out the H' signal and demodulates the Yu' and C' multiplied signals into YH and C signals respectively, reproduces the luminance signal Y from the demodulated signal YH and the YL multiplied signal, and also reproduces the luminance signal and C signal from the C signal. And these Y.

The I and C signals are converted into 525 lines, 30 fields/307 frames/sec progressive scanning RBG signal, and this signal is
Book, 60 fields/60 frames/sec progressive scan RB
Convert to G signal.

[Embodiments of the invention]

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

FIG. 1 is a block circuit diagram showing the configuration of the transmitting side of an embodiment of the present invention, FIG. 2 is a block diagram showing the configuration of the receiving side,
FIG. 3 is a diagram showing the frequency arrangement of each signal. In Figure 1, (1a) is an R signal input terminal, (1b) is a G signal input terminal, and (1c) is a B signal input terminal.
'The V signal is a sequential scanning signal of 525 lines and 30 fields/30 frames/second, and the input R, G, and E signals are sent to A/D converters (8a) * (8b) t (8c), respectively. Given. A/D converter (8a), (8b)
The RGB signal sampled at s (lc) is given to the YIQ conversion circuit (5), and the luminance signal Y, I signal and C
converted into a signal. The luminance signal Y is given to a 4.2M low-pass luminance signal passing filter (6a), and the low-pass component YL is given to a YL O'Yn' multiplex circuit (9).

In addition, the luminance signal Y is given to a high-definition signal passing filter (6b) of 4.2 to 6 MHz, and its high frequency component YH is
It is modulated by a modulator (7a). The modulator (7a) receives 1/1 of the color signal subcarrier frequency fso from the input terminal (1d).
A horizontal modulation wave with a frequency of 2 is given, and a modulator (7
The output of a) is passed through a 4.2 MHz low-pass filter (6C
) to the modulator (7b). Modulator (7b
) is given 525/2 vertical modulation waves from the input terminal (is), and the output of the modulator (7b) is applied to the modulator (7b).
c] to the YtO'Yn' multiplex circuit (9). From the input terminal (1f), the modulator (7c) receives 15
1 time modulated wave is given.

In addition, the engineering signal is filtered through a 1.5 MHz low-pass filter (6
d) to the modulator (7d), and the modulator (7d) receives the color subcarrier frequency f from the input terminal (1g).
A horizontal modulation wave of the same frequency as so is given.

In addition, the C signal is filtered through a 1.5M)h low-pass filter (6
A horizontal modulated wave having the same frequency as frc is applied to the modulator (7e) from an input terminal (ih). The output of the modulator (7d) and the output of the modulator (7e) are given to an adder (8a) and added together. The output of the adder (8a), that is, the color signal C, is transmitted through modulators (7f) and (7g) to YLO'YH'.
A multiplex circuit (9) is provided. The modulator (7f) receives 52574 vertically modulated waves from the input terminal (11), and
The modulator (7g) is given 15 time modulated waves from the input terminal (1j), and the color signal C becomes a two-dimensional frequency modulated signal C' and is sent to the YLC'YH' multiplex circuit ( 9) given to rel. N'l'SO signal converter αQ
has a frame memory and reads out 525 input sequential scanning signals of 30 frames/30 fields/sec at twice the speed every l frame. D/A converter (4a
) converts the read signal into an analog signal and outputs 525 lines from 1 output terminal (2a), 60 fields/30 frames/sec interlaced NTSC! Output as a signal.

In Fig. 2, 525 supplied to the input terminal (1k)
The interlaced NTSC signal of 60 fields/30 frames/sec is processed with high precision through an A/D converter (8d).
Input to 1tlBTV signal converter αυ, 525 lines/3
It is converted into a sequential scanning signal of 0 fields/30 frames/sec and sent to a three-dimensional YLO'YH' separation circuit (12a) and 2
Dimension YL O'YH' is given to the separation circuit (12b). The low-range luminance signal Yt, which is separated in the 8-dimensional Yt, O'Y1 at the separation path (12a), is sent to the selection circuit (15a).
The modulated YII' signal is sent to one input of the selection circuit (
15b), and the modulated color signal C' is applied to one input of the selection circuit (150).

In addition, the YL multiplied signal separated by the two-dimensional Yt, O'YH' separation circuit (12b) and the modulated YH' signal are input to the other input of the selection circuit (15a). The modulated color signal C' is input to the selection circuit (1sc
), respectively. Selection circuit (4
The output Yx of 5a) is given to one input of the adder (8b), and the output of the selection circuit (15b) is fed to the demodulator ('rh).
, ('ri), (?j) via 4.2~6.0M
1-1z high-pass filter (6f). The demodulator (7h) receives the 15 time modulated waves from the input terminal (11), and the demodulator (71) receives the time modulated wave from the input terminal (11).
m), 52,572 vertically modulated waves are sent to the demodulator (7j), and fs is sent to the demodulator (7j) from the input terminal (1n).

A horizontally modulated wave having a frequency of 1/2 of that is provided. The output YH of the high-pass filter (6f) is output from the adder (
8b), and the output Y signal of the adder (8b) is given to the RGB conversion circuit (to).

Also, the output C' of the selection circuit (150) is the demodulator <7k)
, (11) to the demodulators (7m) and (7n). The demodulator (7k) receives 151 time demodulated waves from the input terminal (1o), and the demodulator (71) receives 52574 vertical demodulated waves from the input terminal (1p).
Also, f8 is input to the demodulator (7m) from the input terminal (1q).
The horizontal demodulated wave with the same frequency as c is also demodulated by the demodulator (7n)
A horizontal demodulated wave having the same frequency as fs0 is applied from the input terminal (1r) to fs0. The output signal of the demodulator (7m) is passed through a 1.5M)-1x low-pass filter (6g), and the output Q signal of the demodulator (7n) is 1.5MHz.
are applied to the RGB conversion circuit (to) through the low-pass filter (6h).

The RGB conversion circuit (to) receives these input signals Y, I.

Q is converted into 525 lines, 30 fields/307 L/-m/sec progressive scanning signals R signal output, G signal output and B signal output, and the double scanning converter α→ converts this signal into 525 lines, 60 fields. /60 frames/second progressive scanning signals, and these signals are passed through a D/A converter (4b), (4
c) * Output terminal (2b) via (4d).

(2c) e Output from (2d).

In this way, 525 images were captured on the transmitting side.

The reason for sequential scanning at 30 fields/30 frames/second is that the current NTSC system video signal transmission band is 4.2M.
Hz, and since the above imaging signal is a sequential scanning signal of 525 lines and 30 fields/30 frames/second, the band in which aliasing distortion does not occur in the vertical direction is naturally limited, so the frequency that can be transmitted is limited. The area is like the shaded area YL in the μ-shi plane (horizontal-vertical two-dimensional local wave number area) in FIG. 3(a). Filter (6b)s
(6c), modulator (7a)y ('rb), (7c
) by YH double signal three-dimensional amplitude modulation,
The area of the signal Yu is shown in FIGS.
Shift the frequency to the u' region.

In addition, 2 units consisting of modulators (7f) and (7g)
By dimensional amplitude modulation, the area of color signal C is
and the frequency is shifted to the region C' shown in (b).

At this time, the f-ν plane (time-vertical two-dimensional frequency domain)
FIG. 8(C) shows the YH' signal and the C' multiplied signal frequency region. 525 lines multiplexed in this way, 30
Field/30 frames/second progressive scanning video signal is N
The video signal input to the TSC signal converter α and input to the NTSC signal converter α is once written into the frame memory, read out twice by the increment, and the color subcarrier fso of the read signal is The phase is the same as the current NTSC signal, and the frequency region of the color signal C' on the f-ν plane is the fourth
As shown in Figure (c), it can be received by existing NTSC receivers.

In this way, the signals imaged by sequential scanning of 525 lines and 30 fields/30 frames/second are 525 lines,
It is transmitted as an incremented high-definition TV signal at 60 fields/30 frames/second.

Next, on the receiving side, 525 received.

The 60 fields, 730 frames/second interlaced TV signal is once written into the frame memory of the high-definition TV signal converter αυ via the A/D converter (8d), and is sequentially processed at 525 lines, 30 fields/30 frames/second. It is read out as a scanning video signal. Generally, when the video signal is a moving image, the spectrum of the signal spreads in the time axis direction, so it is strictly impossible to separate each signal in the time-frequency range unless each signal is band-limited on the transmitting side. be. Therefore, in this embodiment, the composite video signal is separated into YLC'YH' in an 8-dimensional frequency domain in the case of a still image, and in a 2-dimensional frequency domain in the case of a moving image. The selection circuits (15a), (15b), and (15c) perform this selection. The signal YH' selected by the selection circuit (15b) is demodulated'a (7h), (7i),
(7j) Signal Y
The signal is demodulated to H, is added to the signal YL by the MJ calculator (8b), and is reproduced into the luminance signal Y. Further, the signal C' is demodulated into a color signal C by a demodulator (7k), <71), and is further demodulated into a color signal C and a color signal by a demodulator (7m) e (7n).
demodulated into a signal. Luminance signal Y obtained in this way
, I signal and Q signal are converted to 525 by the GB conversion circuit Q3.
This is converted into a progressively scanned video signal of 30 fields/30 frames/second. The double scanning converter Q4) has a built-in frame memory and reads out the RGB signals twice at twice the speed for each frame. That is, 525 lines, 30 fields/
525 sequential scanning signals at 30 frames/second.

60 fields/60 frames/sec progressive scan NTSC
It is converted into a signal and outputted via D/A converters (4b) to (4d).

In this way, according to this embodiment, 525
The image is captured by sequential scanning at 30 fields/30 frames/sec, and the image is displayed on the receiving side using 525 sequential scanning signals at 60 fields/60 frames/sec, improving vertical resolution.

In addition, the high-frequency component (high-definition information) YH of the luminance signal is three-dimensionally sub-modulated, frequency-shifted within the current transmission band, and transmitted, and demodulated on the receiving side, thereby improving horizontal resolution.

In the above embodiment, the YH area signal is simply multiplexed into the Ya' area, but in the case of moving images, multiplexing may also be performed with all signals present in the YH' area blocked before multiplexing. good. Similarly, all signals present in the C region may be blocked before the color signals are multiplexed into the 0-head region. By doing so, crosstalk in the case of moving images can be avoided.

In addition, in the above embodiment, 525 lines, 30 fields/3
Although the target is a television signal imaged by sequential scanning at 0 frames/second, the imaging method is not necessarily limited to the above imaging method, and for example, 525 signals.

The signal may be captured by sequential scanning at 60 fields/60 frames/sec and thinned out every other frame.

In addition, in the above embodiment, the horizontal modulation wave for YH double signal modulation is set to f8C/2, but it is not limited to this example (the same effect can be obtained even if the frequency is fso/2 or its vicinity). can get.

〔Effect of the invention〕

As described above, according to the present invention, on the imaging and transmitting sides, 525 aO fields/30 frames/second sequential scanning signals are subjected to eight-dimensional amplitude modulation of the high frequency component YH of the luminance signal Y. The frequency is shifted and multiplexed within the 2 MHz transmission band, converted into an interlaced NTSCTV signal of 525 lines, 60 fields/30 frames/second, and transmitted.On the receiving side, the signal is transmitted with 525 lines, 60 fields/30 frames/second. After converting to a sequentially scanned video signal of YL,
O'.

The YH' signal is separated in a three-dimensional frequency domain in the case of a still image, or in a two-dimensional frequency domain in the case of a moving image, and demodulated into Y, ■, and Q signals, and then further converted into RB, G signals. After converting to 525 lines, 60 fields/60 frames/second progressive scanning video signal for display, it has full communication with the N'['S O color TV signal system and vertical This has the effect of significantly improving resolution and horizontal resolution.

[Brief explanation of drawings]

FIG. 1 is a block circuit diagram showing an embodiment of the transmitting side of the high-definition television signal system according to the present invention, FIG. 2 is a block circuit diagram showing an embodiment of the receiving side, and FIG.
) to (0) are diagrams showing the frequency arrangement of each signal in this embodiment, Fig. 4 is a diagram showing the frequency arrangement of each signal in the conventional high-definition TV signal system, and Fig. 5 is a diagram showing the frequency arrangement of each signal in the conventional high-definition TV signal system.
FIG. 2 is a diagram showing the configuration of a signaling system. (5) -・-Y IQ conversion circuit, (6a) ~ (6h
) - filter, (7a) to (7g) - modulator, (7h
) ~(7n) - demodulator, (8aL(8b)...adder, (9)...YL O'YH' multiplex circuit, αQ・
...NTSC signal converter, αη...High-definition TV signal converter, (12a)・8-dimensional YLC'YH' separation circuit, (
12b) ・Two-dimensional YLC'YH' separation circuit, C...R
GB conversion circuit, ai>... double scanning converter, (X5a
) to (15c)...selection circuit. In each figure, the same reference numerals indicate the same or corresponding parts.

Claims (2)

[Claims] (1) On the transmitting side, the 525-line, 30-field/30-frame/second sequential scanning RBG signal is converted into luminance signals Y, I signal, and Q signal, and the high frequency component Y_H of this luminance signal Y is converted to a vertical spatial frequency. 525/2, three-dimensional amplitude modulation is performed using a carrier wave whose horizontal spatial frequency is 1/2 of the color subcarrier frequency fsc or its vicinity, and whose temporal and spatial frequency is 15 Hz, and the above I signal and Q signal are converted into a color signal C. This color signal C is subjected to two-dimensional amplitude modulation with a carrier wave having a vertical spatial frequency of 525/4 lines and a temporal spatial frequency of 15 Hz, and these modulated signals Y_H', C' and the low level of the luminance signal Y are The area component Y_L is multiplexed, and signal processing is performed to convert this multiplexed signal into an interlaced NTSC signal of 525 lines and 60 fields/30 frames/sec.In addition, on the receiving side, the received NTSC signal is
5 lines, 30 fields/30 frames/second sequential scanning signal, and from this converted signal, Y_L, C', Y_H
' Separate the signal in the three-dimensional frequency domain (horizontal-vertical-time frequency domain) in the case of still images, and in the two-dimensional frequency domain (horizontal-vertical frequency domain) in the case of moving images. YH' signal and C' signal respectively
demodulate into an H signal and a C signal, add this Y_H signal and the Y_L signal in the converted signal to reproduce the luminance signal Y,
Regenerate the I and Q signals from the C signal, and reproduce these Y, I,
Convert the Q signal to R, B, G signals, and convert this converted signal into 52
5 lines, 60 fields/60 frames/sec sequential scanning R
A high-definition television signal system that is characterized by performing signal processing to convert it into a BG signal. (2) 525 captured video signals, 60 fields/
It is a progressive scanning signal of 60 frames/second, and this signal is
Thinned every other frame to 525 lines, 30 frames/3
2. The high-definition television signal system according to claim 1, wherein the signal is converted into a progressive scanning signal of 0 fields/second and subjected to signal processing.