JPH01229590A - Transmitter for color television signal multiplexed with additional signal - Google Patents

Abstract

PURPOSE:To transmit additional signals regardless of moving or still pictures by deleting the high band component of the luminance signal of a NTSC signal for addition of a color TV signal for additional information and limiting the band of a spectrum increasing component in a moving picture state. CONSTITUTION:The oblique high band component of the luminance signal of an existing NTSC signal is deleted and orthogonal amplitude modulation and then the multiplexing of frequency are applied to a color TV signal for additional information having its compressed band by means of said area where the oblique high-band component is deleted. Then the band limitation is applied to the component of said luminance signal with which the spectrum is expanded to the area where the oblique high band component produced in a moving picture state is deleted. Thus it is known that the band where the oblique high-band component of the luminance signal exists is not effectively utilized in terms of visual sense. Therefore, the color TV signal for additional information, even though superposed on said area, is not easily recognized in terms of the visual sense. Thus the existing NTSC signal is not disturbed. Furthermore, the additional signals can be transmitted even in a moving picture state because band limitation is applied to the component with which the spectrum is expanded to a deleted area in the moving picture state.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Field of Industrial Application) This invention maintains compatibility with an NTSC color television broadcasting system, while also providing a signal that is separate from the original color television signal in this system. The present invention relates to an additional signal multiplexing color television signal transmission device for multiplexing a color television signal with an original color television signal and transmitting the same.

(Prior Art) The NTSC system, which is one of the color television broadcasting systems, can be said to be an excellent system that is compatible with black and white television broadcasting and has sufficient performance as a color television broadcasting system. This can be seen from the results of implementation in Japan, the United States, and other countries.

Incidentally, over its long history, the image quality of the NTSC system has been significantly improved since its initial implementation as a result of constant efforts by both the transmitting and receiving sides.

However, in the NTSC system, there is a desire for further improvement in image quality due to the recent spread of large screen displays.

IDT is a method for improving the image quality of the NTSC system.
V (Improved Def'1nitlon
There is a method called Te1evision). This method aims to improve image quality by making full use of the transmitted NTSC color television signal (hereinafter referred to as NTSC signal) on the receiving side.

This IDTV could not be implemented under conventional analog technology, but has become possible due to recent advances in digital technology.

According to this IDTV, compared to the conventional analog system,
Image quality can be significantly improved.

However, since this IDTV is based on the NTSC system, the upper limit of the image quality that can be improved is limited by the NTSC standard. Here, the upper limit items for the system include (1) screen aspect ratio (2) horizontal resolution of 330 Tv lines.

The aspect ratio of (1) is currently 4:3, but it is known that users prefer ratios such as 5:3 or 6:3 (Broadcasting System published by Japan Broadcasting Publishing Association (Editor) (See page 80 of 2 Japan Broadcasting Corporation)).

In addition, the high-definition television broadcasting system (HLGHDeri)
16:
9 aspect ratio may be adopted (CCIR
Report 801-2).

Regarding the horizontal resolution (2), in the NTSC system, 4
．． Since it is specified as 2MHz, the limit is 330Tv. On the other hand, considering the number of effective scanning lines (480 lines), a vertical resolution of 45 OTV lines is possible even with a margin such as overscan. Therefore, at this stage, it is desired to improve the horizontal resolution in terms of horizontal and vertical balance.

As an example of a system that improves the above two items and maintains compatibility with current television receivers, for example, Josep
h L, LoClcero “A Compatible
le Hlgh-Deflnition television
sion System (SLSC) with Ch.
rosinance and aspect R
atio lnpuruvements-8WPTE
Journal, May 1985. below,
The Kono5LSC method will be described.

FIG. 28 shows a spectrum diagram of the 5LSC method.

In FIG. 28, signals of 0 to 4.2 MHz are signals for maintaining compatibility with current television receivers. 4.9-10. The IMF (z signal is an additional signal used to expand the aspect ratio and the resolution of luminance and chromaticity. Therefore, in this 5LSC system, the signal for one station is transmitted using the band for two channels. One channel basically sends a signal similar to the current television broadcast signal, and the other channel sends an additional signal to improve picture quality.

According to such a configuration, channels received by current television receivers do not include additional signals, so
It is considered that there is high compatibility with respect to interference. However, 1
It is not efficient because it occupies two channels per station. Particularly in situations where channel allocation is near the limit, such as in Japan, implementation is expected to be difficult. In addition, when considering intra-station and inter-station transmission, current television broadcasting equipment is
Since it does not have a band that extends to 0 MHz, it is necessary to invest in all new equipment.

From the above, it is preferable to perform transmission within the band of one channel. Moreover, if additional signals can be multiplexed within the baseband of 4.2 MHz, compatibility with current television broadcast equipment such as video tape recorders and transmitters can be achieved.

As one method of multiplexing additional signals to around 4.2 MHz of the baseband, T.Fukinuki et al.

”Extended Derinislon TV F
ully CollICollpatible Exi
sting 5 standards” !EEE T
r,onCommunicatlon Vol,C0M
-32NO, 8, August 1984.

In the NTSC system, in the case of still images, this method uses luminance detail components (approximately 4 to
This is a 6 MHz signal, and is used to multiplex YH (hereinafter referred to as a luminance high frequency signal). Here, the unused area is
In the vertical-time direction spectrum diagram of FIG. The area of the third quadrant is used. In addition, in the figure, C
is a color difference signal.

By the way, this method is applicable only to still images and not to moving images. In the case of video, the spectrum spreads in the time direction and the original NTS
This is because the C signal and the additional signal (luminance high frequency signal Y) I) overlap, making it impossible to separate both signals on the receiving side.

Since the brightness high frequency signal YH is effective for still images, even if the above method can transmit the additional signal only for still images, the objective of improving the resolution of still images can be achieved.

However, when transmitting a signal for enlarging the aspect ratio as an additional signal, the additional signal must be sent not only for still images but also for moving images. Therefore, the above-mentioned additional signal multiplexing method, which can transmit additional signals only for still images, cannot be used to transmit additional signals for expanding the aspect ratio.

In order to solve this problem, it is conceivable to limit the motion component of the current NTSC signal, but doing so is likely to cause unnatural motion as a side effect, and the existing television reception Compatibility with the machine will be impaired.

Further, in the case of a general natural image, the luminance high-frequency signal Y has a much lower level than the low-frequency component, so even if it is multiplexed, it will not interfere with current television receivers. On the other hand, when transmitting an additional signal for expanding the aspect ratio, it is necessary to transmit from high-level low-frequency components to high-frequency components, which poses a problem of interference with the current NTSC signal. In order to solve this problem, it is possible to lower the transmission level of the additional signal, but if this is done, a new essential problem arises in that the signal-to-noise ratio during reception and reproduction deteriorates.

As mentioned above, in order to multiplex an additional signal to expand the aspect ratio within 4.2MHz of the baseband, it is necessary to: ■ Be able to transmit the additional signal regardless of whether it is a moving image or a still image ■ Current televisions The following conditions must be met: there is little interference to the John receiver, and the signal-to-noise ratio (S/N ratio) when receiving and reproducing additional signals must be maintained. However, at present, no method has been developed that can satisfy these two conditions.

(Problems to be Solved by the Invention) As described above, in the conventional additional signal multiplexing color television transmission device that is compatible with the NTSC color television broadcasting system, one broadcasting channel (6MHz) and can transmit color television signals for additional information within the baseband (4.2 MHz) band, but this is limited to still images or transmitting only high-frequency components; It was not possible to transmit additional signals when transmitting low frequency components.

Therefore, the present invention provides additional information that allows color television signals for additional signals to be transmitted within the band of one broadcasting channel and even within the band of the baseband, even when transmitting moving images and low-frequency components. An object of the present invention is to provide a multiplexed color television signal transmission device.

[Structure of the invention] (Means for solving the problem) In order to achieve the above object, this invention complies with the current NTSC
The diagonal high-frequency component of the luminance signal in the signal is deleted, and using this deleted area, the band-compressed color television signal for additional information is subjected to orthogonal amplitude modulation and frequency multiplexed.
Among the luminance signals of the SC signal, components whose spectrum expands to the deletion region of oblique high-frequency components that occur during moving images are band-limited.

(Function) According to the above configuration, since the band in which the diagonal high-frequency component of the luminance signal exists is not visually effectively used, even if the color television signal for additional information is superimposed here, it is not visually effective. Since it is difficult to recognize, it does not interfere with current NTSC signals.

Furthermore, since the band of the component whose spectrum is expanded to the deletion area during moving images is limited, there is no problem in separating the color television signal for additional information from the NTSC signal, and additional information can be transmitted even during moving images.

(Embodiments) Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a transmission device according to an embodiment.

In FIG. 1, 11 is an input terminal for color television signals. This signal has an aspect ratio of 16:9,
It is a sequential scanning (non-interlaced) signal with 525 scanning lines and a frame frequency of 59.94 Hz (hereinafter referred to as 60 Hz). In the drawings, such non-interlaced signals are expressed as 525/60. This signal consists of a luminance signal represented by Y and chromaticity signals represented by I and Q.

The signal supplied to the input terminal 11 is sent to the screen division filter 1.
2. This screen division filter 12 divides the input signal into a portion corresponding to the center portion F1 of the screen F in FIG. 2 and a portion corresponding to the side portion F2. Here, the aspect ratio of the screen center portion F1 is set to 4:3.

Screen center portion F1 output from the screen division filter 12
The signal (hereinafter referred to as the center signal) is sent to the time expansion circuit 1.
3, and the time axis is expanded by 5/4 times. on the other hand,
The signal of the screen side portion F2 (hereinafter referred to as side signal) is expanded four times by the time expansion circuit 14. Figure 3 shows the state of time expansion. Of the effective horizontal scanning period 53JLs in terms of interlacing, 42 μs is allocated to the screen center portion F1, and 11 μs is allocated to the screen side portion F2. This relationship is (42+11):42X (3/4) 5:3,
Basically, it supports an aspect ratio of 5:3, but since it involves overscanning in normal television receivers, assuming an overscan of about 6%,
It can also support an aspect ratio of 6:9. Hereinafter, the description will be made using parameters based on the relationship shown in FIG. 3, but if you do not want to allow overscanning, the parameters described below may be slightly changed.

The center signal is time-expanded by a factor of 5/4, resulting in a band of 0 to 10 MHz. Among the time-expanded center signals, the luminance signal Y is supplied to the luminance high frequency separation circuit 15. This brightness high frequency separation circuit 15 receives input signals from 8 to 8.
It is separated into a 10 MHz brightness high band signal Y and a 0 to 8 MHz brightness low band signal YL.

The brightness high frequency signal YH has its level suppressed by a level conversion circuit 16, and then is converted by a Y encoder 17 into a signal suitable for multiplexing. On the other hand, the luminance low-frequency signal YL is supplied to the NTSC encoder 19 after being subjected to blurring processing in the motion adaptive blurring processing circuit 18 to make it a signal suitable for multiplexing with the luminance high-frequency signal YH and the side signal. . At this time, the spectrum of the luminance low-frequency component YL is limited to a region as shown in FIG. 4(a).

Of the center signals output from the time expansion circuit 13, the chromaticity signal 1. Q is NTSC with color difference band limiting filter 20
After being limited to a band that meets the standard, it is supplied to the NTSC encoder 19. And this NTSC encoder 1
9, the luminance low frequency signal YL is converted into an NTSC color television signal, and then the addition circuit 21
is supplied to

On the other hand, the side signal is time-expanded four times by the time expansion circuit 14, and is made into a signal with a band of 2.2 MHz.

This time-expanded side signal is sent to the time-division color multiplexing circuit 22.
is supplied to This time-division color multiplexing circuit 22 receives color difference signals 1. After band-limiting Q to 0.25 MHz, line sequential multiplexing is performed. Furthermore, by time-division multiplexing this line-sequential multiplexed signal and the luminance signal Y, the signal shown in FIG. 5 is obtained. In this case, the color difference signal I.

The amplitude of Q is set to 1.33 (110,75) times the normal value. This makes it possible to improve the S/N ratio on the receiving side to the same extent as the center color difference signal.

The output of the time-division color multiplexing circuit 22 is outputted by the band compression circuit 23 at 1/30 [second] and 525/4 [in the vertical direction].
c, p, h], the horizontal direction is compressed to a band of 1 FMHzF. The level of this compressed output is suppressed by the level conversion circuit 24, and then converted by the side information encoder 25 into a signal suitable for multiplexing. The spectrum of this converted signal is located in the shaded area in FIGS. 4(a) and (b), and as shown in FIG. 4(a), the center signal is
They are separated in the horizontal and vertical spectral regions.

, the output of the side information encoder 25 is supplied to the adder circuit 21 and added to the output of the NTSC encoder 19. This addition output is added to the luminance high frequency signal Y output from the YH encoder 17 by the addition circuit 26. This addition output becomes a transmission signal.

FIG. 6 shows an example of a specific configuration of the screen division filter 12.

In the figure, the input terminal 1a has an aspect ratio of 16:9.
signal is supplied. This signal is, for example, T-1/
(5,0fsc) (fsc: color subcarrier frequency -3,
This is a digital signal discretized at intervals of 579,545 MF1z). This signal is supplied to one input terminal of the multiplication circuits 2a, 3a and weighted according to the control signals xn, YrL supplied to the other input terminals of the multiplication circuits 2a, 3a.

FIG. 7 shows an example of control signals xn and Yn. Here, U
rL is a timing signal indicating the switching timing between the screen center portion Fl and the screen side portion F2. Time ti indicates the timing of switching from the left screen side portion F2 to the screen center portion F1, and time Tj indicates the switching timing from the left screen side portion F2 to the screen center portion F1.
This shows the retiming of switching to the right screen side portion Fl. This timing signal UrL is transmitted separately from the television signal. The transmitting side sets the switching position between the screen center part Fl and the screen side part F2 according to the content of the image program, and the receiving side forms a screen with an aspect ratio of 16:9 according to the sent timing signal UrL. do. The control signals Xn and YrL shown in FIG.
It has a waveform of a multiplied pulse, and is later time-stretched by (5/4) times,
Since it undergoes twice the time expansion due to interlace conversion, the half width is 2XTX (5/4)X2=1/ (2fs
c) It is equivalent to the integration of a squared sine pulse of 140 ns, and the maximum frequency f laX is fiax = 1/(2X half width) - 3.58 MHz. Further, the control signals xn and Yn in FIG. 7 always have a relationship of xn +YrL-1.

FIG. 8 is a circuit diagram showing an example of a specific configuration of the motion adaptive blurring processing circuit 18.

In this FIG. 8, a luminance low frequency signal YL having a band of 0 to 8 MHz is supplied to the input terminal 1b from the luminance high frequency separation circuit 15 shown in FIG. 1 above.

This luminance low-pass signal YL is supplied to a horizontal/vertical two-dimensional low-pass filter (hereinafter referred to as LPF) 2b which has the shaded area in FIG. Ingredients are removed. This diagonal high-frequency component has little contribution to visual perception, so even if it is deleted, it has almost no effect on deterioration of image quality.

The output of the two-dimensional LPF 2b is supplied to the horizontal HPF 3b, and high frequency components of 4 to 8 MHz are extracted.

This high frequency component of 4 to 8 MHz is subjected to motion adaptive pre-processing. That is, this 4-8M) Lz acid component, the still image processing circuit 4b, and the non-interlaced/interlaced (
(hereinafter referred to as NINT/INT) is supplied to a conversion circuit 6b. As shown in FIG. 9, the still image processing circuit 4b has a frame delay circuit 1c that delays the input signal by one frame, and the sum of the input and output signals of the frame delay circuit 1c is calculated by the addition circuit 2c. , the output signal of this adder circuit 2c is 1/2
The coefficient circuit 2c is designed to reduce the number to 1/2. As a result, an average output of image signals for two frames (in this case, image signals at 1/30 second intervals) is obtained from the 1/2 coefficient circuit 3c.

This average output is supplied to the NINT/INT conversion circuit 5b and converted into an interlaced signal. This NINT
The /INT conversion circuit 5b has a line distribution circuit 1d, as shown in FIG. 10, and the line distribution circuit 1d distributes one frame's worth of signals into signals of odd lines and even lines.

Then, the signal on one line is transferred to the field delay circuit 2d.
By selectively selecting this signal and the signal on the other line by the switch circuit 3d in accordance with the field switching signal, a signal having an interlaced structure is obtained. Here, the output signal of the switch circuit 3d is in the form of an interlaced signal, but since the information for one frame is divided into two fields and transmitted, between the two fields, There is no movement component at all. Therefore, there is no generation of vertical high-frequency components due to so-called interlace folding that occurs when there is movement, so there is no worry of crosstalk to additional signals.

The above NINT/ to which the output of the above horizontal HPF 3b is supplied
The INT conversion circuit 6b performs scanning line conversion by deleting even-numbered line signals among the 525 scanning line signals in a certain frame, and deleting odd-numbered line signals in the next consecutive frame. . Therefore, in this case, the motion component is preserved between two consecutive frames.

The output of the N I NT/l NT conversion processing circuit 6b undergoes predetermined moving image processing by the moving image processing circuit 7b, and then is supplied to the switching circuit 8b. This switching circuit 8b is NI
Either the output of the NT/INT conversion circuit 5b or the output of the moving image processing circuit 7b is selected, and this control is performed by the motion aliasing detection circuit 9b. This motion return detection circuit 9b includes the NINT/INT conversion circuit 6
When the output signal of b has an aliasing component due to movement, the switching circuit 8 selects the output of the video processing circuit 7b.
b is controlled, and when there is no aliasing component, NINT/IN
The switching circuit 8 selects the output of the T processing circuit 5b.
Control b.

Note that details of the moving image processing circuit 7b and the motion aliasing detection circuit 9b will be described later.

Among the components of 0 to 8 M1 (z) output from the two-dimensional LPF 2b, the 0 to 4 MHz components are extracted by subtracting the input and output of the horizontal HPF 3b by the subtraction circuit 10b, and are extracted by the NINT/INT conversion circuit 11b. is converted into an interlaced signal by
The conversion process is the same as that of the NINT/INT conversion circuit 6b described above.

The output of the NINT/INT conversion circuit 11b and the output of the switching circuit 8b are added by an adding circuit 12b.

The reason for using such adaptive operation is as follows.

Regarding motion, since the same signal is transmitted by field repetition, two consecutive fields within one frame (1/30 second) can be treated as a still image. but,
In such a method, movement becomes a deterioration factor. This will be explained with reference to FIG. The figure shows a rectangular national symbol moving horizontally (from left to right) at a constant speed. FIG. 11(a) shows the original signal, in which smooth movement is expressed from field n to field n+3. FIG. 11(b) shows the case of field repetition described above. According to FIG. 11(b), it can be seen that the edge part swings left and right with respect to the center of gravity of the movement. Such discontinuity in the display relative to the continuity of motion is visually recognized as jerky and unnatural motion called motion jerkiness. For example, Makoto Miyahara
Relationship between visual characteristics and image quality for moving images and its application to television signal band compression J NHK Technical Research, 1970,
As reported in Vol. 27, No. 4, pp. 141 to 171, the above-described field repetition has a narrow permissible range in terms of visual characteristics in terms of smoothness of motion.

Therefore, in this embodiment, when the width of movement between two fields becomes large, as shown in FIG. 12(a), the luminance signal Y is Remove horizontal high frequency components. That is, in the motion area, locally field thinning transmission is performed. Therefore, the motion area is 30
The area shown by the broken line in Fig. 12(a), which causes Hz flicker, is the so-called uncovered background, which is the area left after movement, and is not a very useful area in terms of image quality, so it is visually There is almost no deterioration. As shown in FIG. 12(b), on the receiving side, the horizontal high-frequency components of the luminance signal Y can be deleted and reproduction can be performed using a field in which only additional information is superimposed.

FIG. 13 is a circuit diagram showing an example of a specific configuration of the moving image processing circuit 7b of FIG. 8.

In FIG. 13, the output signal of the NINT/INT conversion circuit 6b of FIG. 8 is supplied to an IH delay circuit 1e and an adder circuit 2e. The adder circuit 2e is the IH delay circuit 1
Add the input and output signals of e. The amplitude of this addition output is halved by the 1/2 coefficient circuit 3e, and becomes an average signal of two lines worth of signals.

The two-line average signal outputted from the 1/2 coefficient circuit 3e and the output of the field delay circuit 10e, which will be described later, are compared in terms of absolute value of amplitude by an absolute value comparison circuit 4e. As a result, among the two consecutive field signals,
A more significant signal is determined. This determination signal is supplied to the median filter 5e, and isolated point noise components are removed. The judgment signal from which the noise component has been removed and the signal delayed by one line by the line delay circuit 6e are combined by an OR circuit 7e to form a continuous judgment signal for two lines. Here, when the output of the field delay circuit 10e has a larger amplitude than the line average signal and is determined to be a significant signal, the switch circuit 9e is turned off and the information in the second field is deleted. That is, the area of the n+l field indicated by the broken line in FIG. 12(a) is deleted. This is a determination to perform field thinning by deleting the information in the second field of the interlaced structure.

Next, in exactly the same way as the above process, the field delay circuit 10
The two-line average signal of the output signal of e is sent to the line delay circuit 11.
It is obtained by the e1 adder circuit 12e and the 1/2 coefficient circuit 13e. Then, this two-in average signal and the field delay circuit 1
From the input signal 0e, continuous determination signals for two lines are obtained by the absolute value comparison circuit 14e, the median filter 15e, the line delay circuit 16e, and the OR circuit 17e. Then, when the input signal of the field delay circuit 10e has a larger amplitude than the two-line average signal and is determined to be a significant signal, the switch circuit 19e is turned off, and field thinning is performed to delete the information of the first field. . This means that the broken line portion of the n field in FIG. 12(a) has been deleted.

Since the above video processing is performed in units of one frame, the switch circuit 8e is operated only during one field period when the signal of the first field appears at the output of the field delay circuit 10e and the signal of the second field appears at the input. , 18e are turned on, and the operations described above are performed.

Through the above processing, when there is significant information in either the first field or the second field within one frame, the luminance signal Y is deleted from the two adjacent lines above and below in the other field, and locally Field thinning status is obtained. This signal is processed as field thinning in the motion area by prohibiting field repetition, so that the smoothness of the motion is not impaired.

FIG. 14 is a circuit diagram showing a specific configuration of the motion aliasing detection circuit 9b of FIG. 8.

In this Fig. 14, N I NT/INT in Fig. 8
The interlaced signal output from the conversion circuit 6b is processed using a field delay circuit 1f so that the signals of the first and second fields are simultaneously processed into horizontal and vertical two-dimensional HPFs 2f and 3f.
is supplied to These two-dimensional HPFs 2f and 3f have a pass band defined by the shaded area in FIG. 4. The components of this region are the 8th
Since it has been deleted in the horizontal and vertical two-dimensional HPF 2b in the figure, it does not originally exist. However, in the case of FIG. 8, after this deletion, the NINT/INT conversion circuit 6b
Scan line conversion is performed at As a result, in the case of a moving image, aliasing components occur in the shaded area in FIG. 4 due to this scanning line conversion. This aliasing component is extracted by two-dimensional HPFs 2f and 3f. Here, to extract this aliasing component,
The reason why two two-dimensional HPFs with the same characteristics are used is that when processing a signal in the subsequent signal processing, the first two-dimensional HPF is used as the signal structure. This is because it is more convenient to use a signal structure based on the second field. That is, there is a line offset relationship between the first and second fields, and the center of gravity of the signal is shifted by one line, so two two-dimensional HPFs 2f are provided corresponding to each field.

3f is used. Here, the two-dimensional HPF
The signal structure of the output of 2f is the signal structure of the first field,
In order to use the signal structure of the output of the two-dimensional HPF 3f as the signal structure of the second field, the two-dimensional HPF 2f, 3
Of the outputs of f, only the output of the two-dimensional HPF 3f is delayed for one field period by a field delay circuit 4f, and then both are alternately selected by a switch circuit 5f.

The feature of the operation in FIG. 14 is that the first .
The second field-to-field operation is performed, and no inter-frame operation is performed.

The output of the switch circuit 5f has an interlaced structure. After the absolute value of this signal is taken by an absolute value circuit 6f, it is converted into an aliasing component detection signal by a nonlinear circuit 7f. This converted output is supplied to a switching circuit 8b in FIG. 8 after isolated noise components are removed by a median filter 8f.

FIG. 15 is a circuit diagram showing an example of a specific configuration of the band compression circuit 23, level conversion circuit 24, and side information encoder 25 shown in FIG. Note that in FIG. 15, the band compression circuit 23 and the side information encoder 25 are confused, so for convenience of explanation, the level conversion circuit 24 is shown on the human-powered side, but in principle, the band compression circuit 23 and the side information encoder 25 are It can be inserted anywhere in the signal processing path.

As shown in Figure 4 above, if a signal is transmitted using the area allocated for side information (the shaded area in the figure), the permissible amount of information is 525 vertically per 1/30 second. The amount of information is /4 [c, p, h x horizontal 1 [M7].

The circuit shown in FIG. 15 converts an input signal with a frame frequency of 60 Hz into a signal every 1/30 seconds using a frame thinning circuit 5g.

Because frames are thinned out on the sending side in this way,
On the receiving side, reproduction is performed using frame interpolation. In this case, to reduce the unnaturalness of the movement,
The sum of the input signal and the output signal of the frame delay circuit 1g is taken by the adder circuit 2g, and this is halved by the 1/2 coefficient circuit 3g.
Multiply this to obtain the average output of the signal for two frames. 2D L
PF4g limits the side signal to the spectrum characteristics shown in FIG. 16(a). During transmission, 1/2 of the information is processed by the line thinning circuits 13d and 20d for interlace conversion, so the amount of information is equivalent to 525/4 [c, p, hl XI [MHzl]. The signal obtained in this manner is supplied to a field thinning circuit 5'g, where information is thinned out every frame, resulting in a frame frequency of 30 Hz.

The vertical LPF 6g extracts a signal having the spectrum shown in FIG. 16(b) from the signal having the spectrum shown in FIG. 16(a) output from the field thinning circuit 5g. The adder circuit 7g subtracts its output signal from the input signal of the vertical LPF 6g.

By passing this subtraction output through the horizontal LPF8g, the first
A signal having the spectrum shown in FIG. 6(C) can be obtained. The vertical frequency shifter 9g performs 4-line inversion processing in the vertical direction on this signal, thereby producing the signal shown in FIG. 16(d).
Obtain a signal with the spectrum shown in .

The line thinning circuit 10g performs line thinning processing on the output signal of the vertical frequency shifter 9g, thereby obtaining a signal whose number of scanning lines is 262.5 and one horizontal period is time-expanded to 64 us. The frame frequency of this signal is 3
0Hz, the band is 0-0.5MHz. The line distribution circuit 11g divides the input signal and obtains two signals each having 131 scanning lines. The time compression/time division multiplexing circuit 12g converts the two signals output from the line distribution circuit 11g into one signal.
By compressing the time to /2 and time-division multiplexing the compressed output, a signal having the number of scanning lines of 131×2 in one horizontal period is obtained. As a result, a signal with 131 scanning lines, a frame frequency of 307, and a band of 0 to IMHz can be obtained.

The line interpolation filter 13g converts the signal with 131 scanning lines output from the time compression/time division multiplexing circuit 14g into a signal with 525 scanning lines.

At this time, the signal peak value becomes 1/4 and is distributed over 525 scanning lines. This signal is transmitted every 1/30 seconds, 1/6
Since the output is only for 0 seconds, the line distribution circuit 14
Distribute to odd and even lines using g. Then, after the signal of one line is delayed by one field by the field delay circuit 15g, both signals are selectively selected by the switch circuit 16g according to the field switching signal, so that the number of scanning lines is 262. 5. Obtain a signal with a field frequency of 60 Hz and a band of 0 to IM1'lz.

The output of the vertical LPF 6g is further supplied to a line thinning circuit 17g. This line thinning circuit 17g thins out the number of scanning lines of the input signal to 131, and doubles the time. As a result, a signal with 131 scanning lines, a frame frequency of 30 Hz, and a band of 0 to IMHz can be obtained. This signal is converted to 525 scanning lines by the line interpolation filter 18g, and the peak value is reduced to 1/1.
reduced to 4. Therefore, no total signal energy is converted. After this, this signal is sent to the line distribution circuit 19g1 and the field delay circuit 20g.

The switch circuit 21g produces a signal with 262.5 scanning lines, a field frequency of 60 Hz, and a band of 0 to IMHz.

The outputs of the switch circuits 16g and 21g are sent to the multiplier circuit 22g.
, 23g. The frequency of this subcarrier for orthogonal modulation is (6/7) fs c = 195 f) 4-3.07M
However, fH: is set to the horizontal synchronization frequency, and the phase is inverted for each field. This phase inversion is performed by a phase shift circuit 24g and a switch circuit 25g.

Note that 26g is a phase shift circuit for giving a phase difference of π/2 to the subcarriers supplied to the multiplication circuits 22g and 23g.

The outputs of the multiplier circuits 22g and 23g are supplied to an adder circuit 27g, where the in-phase and quadrature modulation components are summed. A horizontal band pass filter (hereinafter, a band pass filter will be referred to as BPF) removes unnecessary components other than 2 to 4 MHz from this addition output. As a result, a multiplexed signal having a spectrum indicated by diagonal lines in FIG. 4 is obtained. Note that the multiplication circuit 25d
.

The signal input to 26d is a signal having a spectrum shown in a solid line frame in FIG.

FIG. 18 shows another method of band compression.

Vertical 525/4 [c, p, h], horizontal 1 [MT(z
The diagonal component of 0.5 to IMHz is removed from this removed output as shown in Figure 18 (a), and the horizontal component of 0.5 to IMHz is extracted from the removed output as shown in Figure 18 (b).
) Separate as shown. This separated output is set to the frequency (1/
7) f. When folded back to the vertical high frequency range using the carrier wave of , as shown in Figure 18(c), the vertical
c, p, hl can be band compressed to horizontal 0, 5 [MHzl.

According to such a configuration, there is no need to perform field thinning, and information can be transmitted for each field, thereby eliminating deterioration of motion. However, since oblique components are largely removed, the resolution characteristics deteriorate.

FIG. 19 shows Y1 which performs multiplexing processing of the luminance high frequency signal YH.
1 shows an example of a specific configuration of the encoder 17.

In order to transmit the brightness high frequency signal YH, the area marked Y in FIG.
c, p, h] Horizontal 1 to 2 [MHz] are allocated and only the static area portion is multiplexed.

As an effect of reducing noise power at the cost of reducing the total transmission information, the level conversion circuit 16 converts the frequency of 8 to 10 MBz in order to reduce the transmission level and reduce interference when receiving an NTSC television receiver. Decrease the amplitude of the component.

Regarding the transmission of horizontal luminance high-frequency signals, even if the vertical spectrum is limited to some extent, the effect does not deteriorate much, so the vertical LPF 1h is used to transmit 525/8 [c, p,
Restrict to hl. Since we are considering transmitting only still images, the switch circuit 2h extracts one field's worth of information in two frames.

Since this information can be expressed by 131 scanning lines, the line thinning circuit 3h thins out the number of scanning lines to 1/4. Then, the even and odd lines of the signal having 131 scanning lines are transferred to an offset line distribution circuit 4h.
frame delay circuit 5h for only one line information.
After being delayed, the information on both lines is switched at a frame period by a switch circuit 6h and output. As a result, a signal with 65 scanning lines and a frame frequency of 30 Hz is obtained.

The vertical interpolation filter 7h converts this signal into a signal with 525 scanning lines. The offset line distribution circuit 8h is
This signal is divided into odd line and even line signals. The signals of these two lines are processed by a field delay circuit 9h and a field changeover switch 10h, so that the number of scanning lines is 26.
2.5 lines, converted into a signal with a frame frequency of 60Hz. This signal is processed by the next multiplier circuit 11h to have a frequency of (1
2/7) Multiplex modulation is performed using subcarriers whose phase is inverted for each field at f sc [Hz].

As a result, the output signal of the field switch circuit 10h is converted to the region Y in FIG. 4. This conversion signal is
The signal is supplied to the BPF 13e only when the image is a still image via a switch 12h controlled by a still image determination signal. And this BP
F13)1 extracts only the 1-2 MHz components. This extracted output is supplied to the adder circuit 26 in FIG.
Multiplexed with side signals, etc.

FIG. 20 shows a processing block on the receiving side.

In FIG. 20, 41 is an input terminal to which a received signal is supplied. The received signal supplied to this input terminal 41 is decoded by an NTSC decoder 42 into a luminance signal Y and chromaticity signals I and Q. In this embodiment, since all the additional signals are included in the luminance region, the luminance signal output of the NTSC decoder 42 includes the additional signals. Therefore, the luminance signal output of the NTSC decoder 42 is Yl
The signal is supplied to both the l decoder 43 and the side information decoder 44, and is decoded. However, in FIG. 20, in order to simplify the explanation, the NTSC decoder 42, Y
The H decoder 43 and the side information decoder 44 are shown separately, and since the center signal is processed while containing the additional signal, some interference remains in the additional signal. Therefore, as an actual television receiver, NTSC
The signal separation circuits of the decoder 42, the Y)I decoder 43, and the side information decoder 44 operate as a unit, and are configured to prevent unnecessary signals from being input to each decoder 42, 43, and 44.

The 4 to 5 MHz brightness high-band signal YH decoded by the YH decoder 43 is added to the brightness low-band signal YL of the center signal in an adder circuit 45 . As a result, a luminance signal Y having a band of 0 to 5 MHz is obtained.

This luminance signal Y is time-compressed by a factor of 415 in the time compression circuit 46, so that it has a band of 0 to 6.25 MHz.

This time compressed signal is processed by the non-interlaced conversion circuit 47 with a number of scanning lines of 525, a frame frequency of 60) 1z, and a band of 0.
~13MTIz signal.

On the other hand, the side signal decoded by the side information decoder 44 is time-compressed by 1z4 times by the time compression circuit 48. As a result, the number of scanning lines is 525 and the frame frequency is 60Hz.
, a signal in the band 0 to 8 MHz can be obtained.

This time-compressed side signal and the center signal output from the interlace conversion circuit 47 are combined by a screen synthesis circuit 49 and converted into a signal having a large aspect ratio of 16:9. Luminance signal Y1 chromaticity signal 1. output from these four screen synthesis circuits. Q is R, G by the inverse matrix circuit 50.

The signal is converted into a B primary color signal and used for display.

FIG. 21 shows an example of a specific configuration of the side information decoder 44.

In the figure, an additional signal multiplexed composite signal output from an NTSC decoder 42 is supplied to the Y/C separation circuit 11. This Y/C separation circuit 11 converts the input signal into a luminance signal Y
and chromaticity signal C. Of these, the luminance signal Y is supplied to the additional signal extraction filter 21. This additional signal extraction filter 21 extracts an additional signal included in the input luminance signal Y from the input luminance signal Y. The extracted additional signal is supplied to the orthogonal synchronous demodulation circuit 31 and reproduced into a baseband signal using a subcarrier with a frequency of 6/7 fsc (subcarrier frequency). This demodulated output is converted into a television signal as an additional signal by a band compression decoding circuit 41.

Note that the subcarrier for demodulation is generated by the subcarrier recovery circuit 51 according to the additional signal multiplex decoded signal.

A specific example of FIG. 21 is shown in FIG. 22.

In FIG. 22, the horizontal HPF 1j extracts components of 2 to 4 MHz from the input signal of the side information decoder 44.

It is now assumed that the signal being input to the horizontal HPF 1j is an n+1 field signal.

In a signal with 525 scanning lines made from signals of two consecutive fields n and n+1 in one frame, the information on adjacent scanning lines is originally (525/8) [c,
Since the narrow band components of [p, h] are expressed by 525 scanning lines, the correlation is very high and they can be considered to be almost identical signals.

As shown in FIG. 12(b), in the motion area, n
, n+1 fields, only an additional signal whose phase is inverted for each field is multiplexed into one field, and the luminance signal is deleted. On the other hand, in the still image area, in addition to the additional signal that is inverted for each field, there is a luminance signal Y representing the same image.

The output signal of HPFlj is sent to field delay circuit 2j, 1-line delay circuits 3j and 4j, and addition circuit 5j.

6j, 1/2 coefficient circuits 7j, and 8j are supplied to upper and lower line averaging circuits. From this upper and lower line average circuit,
In one field of the moving image area, only the additional signal appears, and in the other field, the additional signal with the luminance signal Y superimposed thereon appears. Further, when the inter-field inversion average is obtained by the addition circuit 9j and the 1/2 coefficient circuit 10j, in the case of a still image,
The luminance signal Y is canceled and only the additional signal is obtained. On the other hand, in the case of a moving image, the luminance signal Y is not canceled out.

Therefore, by selecting the minimum output from the three outputs of the average output of the upper and lower two lines in each field of n and n+1, and the field inversion average output, it is possible to obtain a signal that does not include the luminance signal and consists only of the additional signal. can.

・In other words, the additional signals included in the three modes, the average of the upper and lower two lines in each field of n and n+1, and the field inversion average output, are all the same, and the luminance signal Y is excluded in at least one mode depending on the image content. ing.

This algorithm is determined by the minimum determination circuit 13j. In this case, the signals of the above three modes are transmitted to the absolute value circuit 1.
After the absolute value of the amplitude is taken at step 1j and single pulse noise is removed at median filter 12j, it is supplied to minimum judgment circuit 13j and subjected to minimum judgment. Note that the minimum determination circuit 13j determines that the mode is a still image mode if there are two or more modes that take the same minimum value.

The above is a determination algorithm for the three modes, and since this algorithm performs a type of maximum likelihood determination, it is characterized by fewer malfunctions due to transmission noise and the like.

In order to separate the additional signal and the luminance signal Y, 525 scanning line signals are required. In the still image mode, this signal may be generated from signals of fields n and n+1. Therefore, in the still image mode, the switch circuit 14j
, 15j select the signals of fields n and n+1, respectively.

In the n+1 field processing, the above-mentioned addition circuit 6j and 1/2 coefficient circuit 8j are processed from 262.5 scanning line signals.
The average of the upper and lower lines is taken at , and the phase of the average is inverted by an inverting circuit 16j to generate 262.5 scanning line signals. This signal is selected by the switch circuit 15j, and the original 262.5 scanning line signals are selected by the switching circuit 14j, resulting in a total of 525 scanning line signals. Similarly,
In the n-field processing, the addition circuit 5J11/
The average of the upper and lower lines is taken by the 2-coefficient circuit 7j, and the phase of this is inverted by the inverting circuit 16j, and the original scanning line signal is sent to the Sui-Sochi circuit 14j.

Select with 15j.

The connection states of switch circuits 14j and 15j are controlled by the output of minimum value determination circuit 13j. A valid signal is only for one field period of one frame (two fields, 1/30 seconds). Therefore, this valid signal appears at 1/
Switch circuit 17j, 1 only for 60 seconds, 1 field period
8. i is turned on and this valid signal is supplied to the vertical HPF 19j.

This vertical HPF 19j is (525/2) ± (525/
8) It has a passband of [c, p, h] and extracts the additional signal from the input signal. The extracted additional signals are orthogonally demodulated by multiplication circuits 20j and 21j. The horizontal LPF 22 j converts 0 to IMHz from this demodulated output.
Extract the ingredients. As a result, the number of scanning lines is 262.5,
A signal with a frame frequency of 30 Hz is obtained. This signal is converted into a signal having 131 scanning lines by a line thinning circuit 23j. The vertical spectrum of the signal output from the horizontal LPF 22j is 525/8 [c, p, hl
Since the bandwidth is limited to , the information is preserved even if the signal is converted to a signal with 131 scanning lines by line thinning.

The signal shown in FIG. 16(d) is transmitted by time-division multiplexing two signals with 131 scanning lines, so the original number of 131 scanning lines is transferred to the time division circuit 24j1 and the time expansion circuit 25j. After returning to the two signals, the line superimposing circuit 26j converts it into a signal with 262.5 scanning lines. The spectrum of this signal is shown in FIG. 16(d).

After that, this signal is processed by the line interpolation circuit 27j to convert the number of scanning lines to 5.
Convert to 25 signals. Next, when this signal is shifted by (525/8) rc, p, hl using the vertical frequency shifter 28j, a signal having the spectrum shown in FIG. 14(c) is obtained.

On the other hand, the signal on the multiplication circuit 21j side has 131 scanning lines and has a spectrum as shown in FIG. 16(b). This signal is processed by the line interpolation circuit 29j, and the number of scanning lines is 5.
After being converted into 25 signals, they are added to the output of the vertical frequency shifter 28j in an adder circuit 30j. As a result, the adder circuit 30j outputs a signal having the spectrum shown in FIG. 16(a). However, this signal is 1/30
Since the signal appears once every second, the frame delay circuits 31j and 32j have a delay amount of 1/60 second.

An adder circuit 33j and a 1/2 coefficient circuit 33 generate a frame interpolation signal, and a switch circuit 35j selectively selects this signal and the output of a frame delay circuit 31j every 1/60 seconds, so that the number of scanning lines is 525. , a signal with a frame frequency of 607 is obtained.

By the way, as shown in FIG. 23, the frame interpolation signal is simply the average of the signals of the previous and subsequent frames, and therefore has an element that causes unnatural motion. Therefore, the motion detection circuit 36j detects the amount of motion of the image, and uses the detection output to control the high frequency component of the frame interpolation signal. That is, when there is movement, the unnaturalness of the movement is eliminated by suppressing the high frequency components of the frame interpolation signal.

Note that the high-frequency component of the field interpolation signal output from the 1/2 coefficient circuit 34j is extracted by the horizontal LPF 37j to which this frame interpolation signal is supplied and the addition circuit 38j that performs subtraction processing on the input/output signal of this horizontal LPF 37j. It will be done. The amplitude of this high frequency component is controlled by the multiplication circuit 39j according to the motion detection output. This control output is applied to the horizontal LPF 37 j in the adder circuit 40j.
It is added to the low-frequency component output from.

The output of the "switch circuit 35" is a level conversion circuit 41 having characteristics opposite to those of the level conversion circuit 24 on the transmitting side shown in FIG.
It is converted to the original signal at j. This signal is sent to color decoder 4
2j is decoded into a luminance signal Y1 and chromaticity signals I and Q.

FIG. 24 shows an example of a specific configuration of the color decoder 42j.

Here, the number of scanning lines is 525, and the frame frequency is 60Hz.
Since we are considering a signal of By doing so, continuous chromaticity signals I and Q are obtained.

The four screen synthesis circuits shown in Fig. 20 basically have the function of temporally switching between the center signal and the side signals to create a wide aspect ratio, but their input section has the function shown in Fig. 25. As shown in the figure, a level adjustment circuit is provided in the input section to make the seams between the center part of the screen and the side parts of the screen less noticeable.

A signal as shown in FIG. 26 is superimposed on an unused line during the vertical retrace period. The DC level is based on the center brightness level of 501RE.

First, the frequency is 3.07 (= (6/7) fsc) [
M) lz], the signal Sl with a phase of 0 [rad] is at least 6
〜7 cycles or more, used as a phase reference for the side information decoding carrier wave, and 50 or 10 cycles for the side luminance signal.
0IRE is used as a reference signal for bright adjustment. next,
Similarly, frequency 3.07 [MHz], phase π/4 [ra
d] signal S2 is sent, and the side chromaticity signal 1.d] is sent. Q level standard.

Next, a color burst signal S3 with a frequency of 3.58 MHz and an I-axis phase is sent, and a center chromaticity signal 1. Q level standard. Next, a switching position signal S4 between the screen center portion F1 and screen side portion F2 in FIG. 2 is transmitted using a binary NRZ signal. On the receiving side, switching position signals S of the screen center portion Fl and screen side portion F2 expressed in digital data are received.
4, a screen with an aspect ratio of 16:9 is synthesized from center signals and side signals.

The reference signal explained in FIG. 10 is NT in FIG.
It is output from the SC decoder 42. Then, the side luminance signal Y1, the side chromaticity signal 1. Controls the level of Q.

Since this control is performed in parallel with the same content for each signal Y, I, and Q, this control will be explained below using control of the side luminance signal Y as a representative. A multiplier circuit 1g multiplies the level of the side luminance signal MY output from the side information decoder 44.
supply to. A subtraction circuit 2g calculates the difference between the multiplication output of the multiplication circuit 1g and the center luminance signal Y output from the NTSC decoder 42. This subtraction output is supplied to an integration circuit 4g via a switch circuit 3g that is turned on only during the subtraction processing period of the subtraction circuit 2g, and is subjected to integration processing. This integral output is supplied to the multiplication circuit 4g as a control signal to control the amplitude level of the side luminance signal Y. As a result, feedback is applied so that the error output output from the adder circuit 2g becomes 0, and the side luminance signal Y and the center luminance signal Y
The amplitude level is made to match.

Similarly, chromaticity signal 1. Q is also controlled so that the amplitude level is equal on the side and center sides, so that there is no difference in brightness and chromaticity between the screen center part F1 and the screen side part 2.

FIG. 27 shows an example of a specific configuration of the YH decoder 43 shown in FIG. 20.

The brightness high-frequency signal Y11 is 1 field (vertical (525
/8) [c, p, h co, horizontal 4~5MHz) information 1
Each frame is divided into two frames and transmitted.

In this case, since the center signal is only for a still image, two fields of field information for 262.5 scanning lines are prepared using a field delay circuit 1m, and these are supplied to a two-dimensional filter 2m. , vertical (525/2) ± (52
5/16) Extract [c, p, h], horizontal 1-2 [MHz] components. Since this signal is valid only during one field period on one side of one frame period, only the valid signal is taken out by the switch circuit 3m. The extracted signal is supplied to the multiplication circuit 4m, and the frequency (12/7) fs
It is demodulated using the carrier wave c.

The horizontal BPF 5m extracts 4 to 5 MHz components from this demodulated output to obtain a signal with 65 scanning lines and a frame frequency of 30 Hz. This signal for two frames is transferred to a frame delay circuit 6m.
is used to supply the double-speed line synthesis circuit 7m, and the number of scanning lines is 1.
31. Convert to a signal with a frame frequency of 15 Hz. This means that the original signal has been reproduced.

Next, for the first one field period, the switch circuit 8m is closed and the output of the double-speed line synthesis circuit 7m is written into the frame delay circuit 9m. Then, during the next three field periods, the switch circuit 8m is connected to the frame delay circuit 9m side, and the same signal is repeatedly selected. This selection output appears to be a signal with 131 scanning lines and a frame frequency of 60H2, so with a line interpolation circuit of 10m, the number of scanning lines is 525,
The frame frequency is converted to 60Hz. This conversion output is supplied to a level conversion circuit 12m through a switch circuit 11m that is turned on only when determining a still image. This level conversion circuit 12m has characteristics opposite to those of the level conversion circuit 16 on the transmitting side (see FIG. 17), and converts the amplitude level of the input signal to the original level. This converted output is supplied to an adder circuit 45 in FIG. 18 and added to the center signal.

According to this embodiment described in detail above, the following effects are achieved.

(1) Interference with current NTSC signals can be eliminated.

This removes the diagonal high-frequency components of the luminance signal Y in the current NTSC signal, and removes this removal area (the area shown with diagonal lines in Figure 4, i.e., horizontal spatial frequency of 2M7 or more, vertical spatial frequency (3X 525/8)). This is because the band-compressed color television signal for additional information is subjected to orthogonal amplitude modulation and frequency multiplexed using the frequency band (in the region above ) cph). In other words, since the band in which the oblique high-frequency component of the luminance signal Y exists is not visually utilized effectively, even if a color television signal for additional information is superimposed thereon, it will not be recognized visually. No interference with current NTSC signals occurs.

(2) Additional information can be transmitted even in the case of moving images.

This is the component whose spectrum expands to the deletion area in the luminance signal Y during moving images, that is, the horizontal spatial frequency is 2.
MHz or higher, vertical spatial frequency is (3×525/8)c
This is because components below pH are partially thinned out in the field.

Although one embodiment of the present invention has been described above in detail, the present invention is of course applicable to cases other than transmitting a signal for expanding the aspect ratio as a color television signal for additional signals.

[Effects of the Invention] As described above, according to the present invention, color television signals for additional information can be transmitted using only the bandwidth for one broadcasting channel or the baseband bandwidth, and even in the case of moving images. Furthermore, even when low-frequency components are included, the signal can be transmitted without causing the same interference as the current NTSC signal.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing the configuration of an embodiment of the present invention, and FIG.
5 to 5 are diagrams for explaining the operation of FIG. 1, and FIG.
The figure is a circuit diagram showing an example of a specific configuration of the screen division filter shown in Fig. 1, Fig. 7 is a diagram for explaining the operation of Fig. 6, and Fig. 8 is a motion adaptive pre-processing shown in Fig. 1. 9 is a circuit diagram showing an example of a specific structure of the still image processing circuit shown in FIG. 8; FIG. 10 is a circuit diagram showing an example of the specific structure of the still image processing circuit shown in FIG. 8; FIG. A circuit diagram showing an example of a specific configuration of an INT conversion circuit, FIG. 11 and FIG.
Fig. 2 is a diagram for explaining the operation of Fig. 8, Fig. 13 is a circuit diagram showing an example of a specific configuration of the video processing circuit shown in Fig. 8, and Fig. 14 is a diagram for explaining the motion loop detection shown in Fig. 8. A circuit diagram showing an example of a specific configuration of the circuit, FIG. 15 is a circuit diagram showing an example of a specific configuration of the band compression circuit, level conversion circuit, and side information encoder shown in FIG. 1, and FIGS.
The figure is a diagram for explaining the operation of FIG. 15, FIG. 18 is a diagram for explaining another band compression method, and FIG. 19 is a circuit showing an example of a specific configuration of the YH encoder shown in FIG. 1. 20 is a circuit diagram showing the configuration of an additional signal multiplexing television signal transmission device, FIG. 21 is a circuit diagram showing an example of a specific configuration of the side information decoder shown in FIG. 20, and FIG.
The figure is a circuit diagram showing an example of a specific configuration of the circuit in FIG.
Fig. 23 is a diagram for explaining the operation of Fig. 22;
The figure is a circuit diagram showing an example of a specific configuration of the color decoder shown in FIG. 22, FIG. 25 is a circuit diagram showing an example of a specific configuration of the screen synthesis circuit shown in FIG. 27 is a diagram showing the basic signal sent to make the seam between the screen and the side part of the screen inconspicuous. FIG. 27 is a diagram showing the Y shown in FIG. FIG. 29 is a diagram for explaining different examples of conventional transmission methods. 11...Input terminal, 12...Screen division filter, 1
3.14... Time expansion circuit, 15... Luminance high frequency separation circuit, 16.24... Level conversion circuit, 17... Y
I encoder, 18...Motion adaptive blur processing circuit, 19
NTSC encoder, 20 Color difference band limiting circuit, 21.26 Adding circuit, 22 Time division color multiplexing circuit, 23 Band compression circuit, 25 Side information encoder. Applicant's Representative Patent Attorney Takehiko Suzue Figure 9 1d District 10 Figure 13 ICPN 1 (a) 16 (b) Mu (d) Figure 23 Figure 24U2J

Claims (1)

[Claims] The horizontal spatial frequency is faMHz, and the vertical spatial frequency is (52
5/2) Diagonal high-frequency components with a horizontal spatial frequency of fxMHz or more and a vertical spatial frequency of fycph or more of the NTSC color television signal, which is cph, are deleted,
and the horizontal spatial frequency is fx or higher and the vertical spatial frequency is fyc regarding the movement between fields within one frame.
The component below ph has a luminance signal that has undergone motion suppression processing, has a scanning structure of 525 scanning lines, a field repetition frequency of 60Hz, and a 2:1 interlace, and has an aspect ratio of 4:3. a first color television signal generating means for generating a first color television signal, and a band having a horizontal spatial frequency of 1/2 (fa-fx) or less and a vertical spatial frequency of (525/2)-fycph or less; with 525 scanning lines and 30
a second color television signal generating means for generating a second color television signal having a frame repetition frequency of Hz and a scanning structure of 2:1 interlace; (n/m)
fsc=kf_H (fsc: color subcarrier frequency, f_H
: horizontal synchronization signal frequency, m, n, k: integer) modulation means for performing orthogonal amplitude modulation using a carrier wave whose phase is inverted for each field; a modulated output signal of this modulation means and the first color television; An additional signal comprising frequency multiplexing means for frequency multiplexing the first color television signal output from the signal generating means using the oblique high frequency component deletion area to obtain a transmission signal. Multiplexed color television signal transmission equipment.