JP2598549B2 - Television signal transmission system and its reproducing apparatus - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a television signal transmission system or a reproducing apparatus, and in particular, has compatibility with a current television system, an aspect ratio of 4: 3 or more, and The present invention relates to a high-definition wide-aspect television signal transmission system for superimposing high-frequency signals such as vertical and horizontal signals on a masking area of a section, or a television signal reproducing apparatus.

Conventional technology Conventionally, in order to transmit video signals such as HDTV signals with an aspect ratio larger than 4: 3 while maintaining compatibility with the NTSC system, either cut off both sides of the wide aspect image or blacken the top and bottom of the NTSC image. Or one of the methods has been proposed.

In the latter case, the vertical region is superimposed with a high-frequency signal of a horizontal signal or another signal such as an audio signal in a vertical region in a blackish region (called a masking region), so that a wide band and a high band are obtained when reproduced by a wide aspect receiver. Proposals have been made to improve the image quality, etc., and considering the interference with the current television receiver reproduction screen, the waveform of the masking signal of the transmission signal shown in FIG. 10 is an improved NTSC signal waveform diagram. As shown in period 42, the black level is set higher than the NTSC prescribed level (refer to the pedestal black level in period 41 in FIG. 10), and the vertical or horizontal high-frequency signal is superimposed below the black level. I have.

FIG. 9 is a block diagram of a conventionally proposed high definition wide aspect television signal transmission system.

In Fig. 9, 21 is the number of scanning lines 1125, aspect ratio
16: 9, a signal source such as a high-definition camera for deriving a high-definition signal with an interlace ratio of 2: 1, 22, 23 is a scanning line number converter, 24, 25 is a position converter, 26 is an NTSC encoder, 2
7 is an output terminal.

In FIG. 9, the number of scanning lines 11 derived from the signal source 21 is 11
25 present, the aspect ratio of 16: 9 HDTV signal of, NTSC effective scanning lines as shown in the vertical direction of the low-frequency luminance signal Y _L and the chrominance signal I, the signal 32 of FIG. 2 by the scanning line number converter 22 and Q The number of scanning lines is converted to 360, equivalent to the central area of 480, and 2:
Return multiplexing by one sub-sampling (this is 2
Forming one image in the field). Further, 120 present corresponding to upper and lower ends region of the NTSC effective scanning lines as shown in the vertical high-frequency luminance signal Y _H to the signal 34 of FIG. 2 HDTV signal from the signal source 21 in the scanning line number converter 23 The number of scanning lines is converted and the signal is multiplexed by 2: 1 sub-sampling.

Next, the position converters 24 and 25 convert 360 vertical low-frequency components and 120 vertical high-frequency components output from the number-of-scanning-line converters 22 and 23 into NTSCs with 525 scanning lines and an aspect ratio of 4: 3.
As shown in signals 33 and 35 in FIG. 2, 360 vertical low-frequency components are placed in the center area of the screen, and vertical high-frequency components 120
Books are placed in the upper and lower ends of the screen.

Finally, the NTSC encoder 26 uses the position converter
The conversion output signals from 24 and 25 are synthesized, and the number of scanning lines is 525,
Convert to 4: 3 aspect ratio NTSC signal (Signal 3 in Fig. 2)
6).

When the high-definition wide-aspect television signal is reproduced by the current NTSC receiver, the form of the transmission signal is changed so that the vertical high-frequency component superimposed on the upper and lower ends of the screen does not disturb, as shown in FIG. It is crafted as shown in the figure. That is, the pedestal black level on which the color burst signal is superimposed is set higher than the specified level 0IRE of the NTSC (see the pedestal black level in the areas 41 and 42 in FIG. 10), and the vertical high-frequency luminance signal is converted to the pedestal black level. When the signal is superimposed on the following and reproduced by an NTSC receiver, the upper and lower ends of the screen are blackened.

Problems to be Solved by the Invention <Problem 1> As a transmission method of a television signal, as described above, a high-frequency signal such as a vertical or horizontal signal superimposed on a masking area at the upper and lower portions of a screen on a transmitting side is converted into a color burst signal. The pedestal black level to be superimposed is set below the black level (see period 42 in FIG. 10), and the pedestal black level is DC-clamped by the receiver during the blanking period so that it does not appear on the playback screen of the NTSC television receiver. In the conventional method,
Although there is no problem with commercially available NTSC television receivers that reproduce the black level by the pedestal clamp, after the sync tip clamp as shown in FIG. In the case of a television receiver having a black level, there is a problem that a vertical or horizontal high-frequency signal superimposed on a masking area is also reproduced.

<Problem 2> Also, when a signal transmitted from the transmission side is received and reproduced by an NTSC receiver by the above-described method, for example, the noise component generated in the signal transmission system and the television receiver is the same as described above. As a result of being superimposed on the vertical high-frequency signal component and the audio signal in the masking area, and also by emphasizing the superimposed signal component in the masking area by contour enhancement of the mid-high frequency component that is usually performed in a television receiver, There has been a problem that crushed noise appears in upper and lower blackish areas of the television receiver playback screen.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention has a compatibility with the NTSC color television transmission system, and masks the upper and lower portions of the screen, as described in claim 1. In a high-definition wide-aspect television signal transmission system in which a vertical high-frequency signal or a horizontal high-frequency signal is superimposed on the masking area, the phase of the vertical high-frequency signal or the horizontal high-frequency signal is inverted for each scanning line and each frame. Color subcarrier f _SC
The area is color sub-carrier f _{SC in the} “time-vertical” two-dimensional frequency domain.
Means for converting the frequency with a carrier wave having a conjugate relationship with the masking area, superimposing the color burst signal in the masking area to a level at which a color killer works in an NTSC receiver, and scanning each of the masking areas. The line is provided with means for superimposing the reference signal for demodulating the vertical high band signal or the horizontal high band signal.

Further, in a reproducing apparatus of a high-definition wide aspect television signal transmission system, as described in claim 2, a means for detecting a black level for each scanning line, and a detection value of the detecting means. Pedestal black level (0IR
A means for detecting a masking signal on which the high-frequency component is superimposed by comparing with E) and a means for clipping a superimposed signal portion in the luminance signal in the masking area are provided.

Alternatively, the reproducing apparatus may further comprise means for detecting a black level for each scanning line, as described in claim 3.
The detection value of this detection means and the specified pedestal black level (0I
RE), a means for detecting a masking signal in which the high frequency component is multiplexed, a means for generating a blanking signal or a black burst signal, and switching the masking signal to a blanking signal or a black burst signal. And switching means. Note that the black burst signal is a flat portion where the video signal period following the color burst signal has a flat black level.

Function Compatible with the NTSC color television transmission system, in a high-definition wide-aspect television signal transmission system in which the upper and lower parts of the screen are masked and a vertical high-frequency signal or a horizontal high-frequency signal is superimposed on the masking area. the vertical high-frequency signal or color subcarrier phase is inverted horizontal high frequency signal for each scanning line and each frame f _sc Ikii the "time - vertical" 2
Means for performing frequency conversion by a carrier having a conjugate relationship with the chrominance subcarrier _fsc in the dimensional frequency domain and superimposing it on the masking area;
The NTSC receiver has a means for suppressing the color killer to a working level and a means for superimposing the reference signal for demodulating the vertical high-frequency signal or the horizontal high-frequency signal on each scanning line in the masking area. When a high-definition wide-aspect signal formed in such a configuration is reproduced on a current NTSC receiver, the vertical or horizontal high-frequency signal superimposed on the masking area is reproduced as a chroma signal after Y / C separation. In addition, this chroma signal causes a color killer during chroma demodulation (because the color burst signal is kept low). For this reason, the current NTSC receiver playback screen is not affected at all, and when played back on a wide aspect receiver, a wide aspect image of wideband and high quality can be played back.

The reproducing apparatus detects a masking signal on which the high-frequency component is superimposed by comparing a detection value of the detection means with a prescribed pedestal black level (0IRE) by means of detecting a black level for each scanning line. And means for clipping the signal in the masking area, it is possible to reproduce a clear image without obstruction such as unsightly noise in blackish areas above and below the screen.

Also, the reproducing apparatus compares a detection value of the detection means with a prescribed pedestal black level (0IRE) by means of a means for detecting a black level for each scanning line, and outputs a masking signal on which the high frequency component is multiplexed. In the case where the detecting means, the means for generating a blanking signal or a black burst signal, and the means for switching the masking signal to the blanking signal or the black burst signal are similarly unsightly in the black areas at the top and bottom of the screen. A clear image without interference such as noise can be reproduced.

Embodiment FIG. 1 is a block diagram of an embodiment of an encoder unit used for a television signal transmission system according to the present invention.

In Fig. 1, 1 is the number of scanning lines 1125, aspect ratio
16: 9, a signal source such as a high-definition camera for deriving a high-definition signal having an interlace ratio of 2: 1; 2, a vertical filter for separating the high-definition signal from the signal source 1 into a low-frequency component and a high-frequency component in the vertical direction; And 7 are scanning line number converters for converting the number of scanning lines of the low frequency component and the high frequency component, respectively.
4 and 10 are the same position converters, 5 is an NTSC encoder, 6 and 11 are adders, 8 is a low-pass filter in the horizontal direction, 9 is a frequency shift circuit, 12 is a color burst signal and a vertical high band superimposed on a masking period. A signal generating circuit 13 generates a reference signal for signal demodulation. Reference numeral 13 denotes an NTSC signal output terminal having 525 scanning lines, an aspect ratio of 4: 3, and an interlace ratio of 2: 1.

FIG. 2 is an operation explanatory view showing a signal conversion process of each unit in the block of FIG.

In FIG. 1, the number of scanning lines 11 derived from the signal source 1 is 11
25 high-vision signals (signal 31 in Fig. 2) with an aspect ratio of 16: 9 are separated by the vertical filter 2 into low-frequency luminance signals Y _L and low-frequency signals I and Q and high-frequency luminance signals Y _H in the vertical direction. is, the low frequency luminance signal Y _L and the chrominance signal I in the vertical direction, Q is the number of scanning lines converter 3, as shown in the second diagram of the signal 32, corresponding to the center region of the NTSC effective scanning lines 480 360 The number of scanning lines is converted to a book, and the book is wrapped and multiplexed by 2: 1 sub-sampling. Further, the vertical high-frequency luminance signal Y _H is the scanning line number conversion unit 7, as shown in the signal 34 of FIG. 2, the number of scanning lines, 120 corresponding to the upper and lower ends region of the NTSC effective scanning lines 480 The signal is converted and multiplexed by 2: 1 sub-sampling.

Next, the vertical low-frequency luminance signal output from said scanning line number converter 3 Y _L and the chrominance signal I, Q by the position transducer 4,
As shown by the hatched portion as the signal 33 in FIG. 2, the color signals I and Q are arranged in the central region of the NTSC screen, and the color signals I and Q are
After modulation, it is vertical low frequency luminance signal Y _L and the frequency-multiplexed, are input to the adder circuit 6.

The vertical high-frequency luminance signal Y _H outputted from the scanning line number converter 7 by horizontal low-pass filter 8, after being band-limited to a region shown in the FIG. 3 (a), the color in the frequency shifting circuit 9 the subcarrier f _SC is frequency shifted in the hatched area a in FIG. 3 (b). Note that the vertical high-frequency luminance signal Y _H is band-limited by the horizontal low-pass filter 8, May be shifted to the shaded area B in FIG. in this case, (A region C in FIG. 3 (c)) appearing on the low-frequency side of FIG.

The color subcarrier f _SC and the carrier used in the frequency shift circuit 9 4 (a) and 4 (b), respectively, and the characteristics in the "time-vertical" two-dimensional frequency domain are shown in FIGS. 4 (a) and 4 (b), respectively. 4 (a) and 4 (b), each circle represents a scanning line, and an arrow therein represents a phase. Assuming that the upward arrow has the phase θ, the downward arrow has the phase θ + π.

As described above, the frequency-shifted vertical high-frequency luminance signal
Y _H ′ is supplied to a position converter 10 which converts this signal to an NTSC signal as shown in signal 35 of FIG.
Arrange them in the upper and lower ends of the screen. The converted output signal is supplied to the adder circuit 6 and combined with the output signal from the encoder circuit 5 indicated by the signal 33 in FIG.
This forms an NTSC signal with an aspect ratio of 4: 3.

Since the vertical high-frequency luminance signal output from the position converter 10 is processed as a chroma signal, this area (the masking area at the top and bottom of the screen) is colored on the NTSC receiver playback screen. For this reason, in the present invention, the level of the color burst signal on the transmitting side shown in FIG. 5 (a) is reduced in the above-mentioned area or eliminated as shown in FIG. 5 (b), and the NTSC receiver is used. The color killer works to prevent the color from sticking. In the wide aspect television receiver, a reference signal is burst-inserted on the front porch side of the horizontal synchronizing signal as shown in FIG. 5B for demodulating the frequency-shifted vertical high-frequency signal. The above processing is performed by the signal generating circuit 12 for the color burst signal and the reference signal and the adder 11 for superimposing the signal from the signal generating circuit 12 on the television signal, and from the output terminal 13,
The NTSC signal indicated by signal 36 in FIG. 2 is derived.

Next, an embodiment of a decoder section for reproducing the NTSC signal obtained as described above will be described with reference to FIG.

In FIG. 6, reference numeral 200 denotes an input terminal of the NTSC signal, 201
Is a line dividing circuit for separating the signal in the center area of the screen and the vertical high frequency signal shifted in frequency at the upper and lower ends of the screen.
/ C separation circuit, 203 is NTSC decoder circuit, 204 is 3 scanning lines
V expansion circuit extending from 60 lines to 480 lines, 205 is an adding circuit, 206 is a horizontal band-pass filter, 207 is a horizontal frequency shift circuit, 208 is a V expansion circuit that extends scanning lines from 120 lines to 480 lines, 209 is a vertical frequency shift circuit, 210
Denotes a matrix circuit, 211 denotes a scanning line conversion circuit, and 212 denotes an output terminal.

In FIG. 6, a high-definition wide aspect television signal input to an input terminal 200 is
Supplied to 1. The line dividing circuit 201 counts the number of scanning lines, or detects whether the reference signal is superimposed on the front porch of the horizontal synchronization signal of each scanning line as shown in FIG. is separated into a signal V _c of the vertical high-pass signal Ve and the screen center area of the screen top and bottom surfaces end as shown in signal 35 and 33 in FIG. Subsequently, the signal V _{C in the} center area of the screen is
The Y / C separation circuit 202 separates the signal into a Y signal and a C signal,
After IQ demodulation by the decoder 203, V
The data is supplied to the expansion circuit 204. The V decompression circuit 204 in the vertical direction of the scanning line extends 480 360 present, the vertical low-frequency luminance signal Y _L is the adding circuit 205, color demodulation signals I, Q are supplied to the matrix circuit 210. Further, the vertical high-frequency signals Ve at the upper and lower ends of the screen output from the line dividing circuit 201 are band-limited by the band-pass filter 206 to a region shown by oblique lines in (b) or (c) of FIG. The signal is guided to a frequency shift circuit 207, and the frequency shift circuit 207 shifts the frequency to the area shown in FIG.
After extending the scanning lines 480 to 120 present by, it is taken out by the frequency shift circuit 209 of the vertical signal as a high frequency luminance signal Y _H of the vertical. Also, the vertical high-frequency luminance signal Y _H is
Is combined with the low frequency luminance signal Y _L of the vertical output from decompression circuit 204, it is input to the matrix circuit 210. The matrix circuit 210 the Y _H + Y _L, I, and Q is converted into RGB signals, and supplies the scanning line conversion circuit 211. The scanning line conversion circuit 211 converts the signal into a sequential scanning signal having 525 scanning lines and an aspect ratio of 16: 9, and outputs 525 scanning lines and an aspect ratio of 1 from an output terminal 212.
6: 9, derive RGB signals for progressive scanning.

FIG. 7 is a block diagram of an embodiment of a reproducing apparatus according to the present invention. When a high-definition wide-aspect television signal transmitted from a transmitting side is received and reproduced by an NTSC receiver, noise components or contour correction are performed. Thus, noise in the form of squash does not appear in the upper and lower blackish areas of the television receiver playback screen. In this embodiment, the current
The above object is achieved by adding a circuit shown by a dashed line in FIG. 7 in the NTSC receiver.

In FIG. 7, 51 is an antenna, 52 is a tuner, 53
Is a video intermediate frequency filter, 54 is a video detection circuit, 55 is YC
Separation circuit, 56 is a contour compensation or high frequency emphasis circuit, 57 is a clip circuit (57a is a resistor, 57b is a clip diode, 57c
Is a clip level adjuster), 58 is a sync tip clamp circuit, 59 is a comparator, 60 is a volume, 61 is a switching circuit, 62 is a sync separation circuit, 63 is a color demodulation circuit, 64 is a matrix circuit, and 65 is a CRT for display. It is. The NTSC improved high-definition wide-aspect television signal transmitted from the transmitting side is received by the antenna 51, frequency-converted by the tuner 52 to the intermediate frequency band,
After band limitation at 53, the video signal is extracted as a video baseband signal shown in FIG. 10 by a video detection circuit 54, and is separated into a luminance signal Y and a chroma signal C by a YC separation circuit 55. This luminance signal Y is supplied to a contour compensation (high-frequency emphasis) circuit 56, a sync tip clamp circuit 58, and a synchronization separation circuit 62. The contour compensation (high-frequency emphasis) circuit 56 performs contour compensation (high-frequency emphasis) of the Y signal. As a result, the superimposed signals in the masking areas at the upper and lower ends of the screen are also emphasized, and in some cases,
Signals that exceed the pedestal black level in the masking signal in region 42 of the figure also appear. For this reason, in the clip circuit 57 including the resistor 57a, the clip diode 57b, and the clip level adjusting circuit 57c, only the superimposed signal in the masking area at the upper and lower ends of the screen is switched by switching of the switching circuit 61 connected to the clip diode 57b (see FIG. The signal in the period B of the area 42) is clipped at its upper end. The switching control signal C _W of the switching circuit 61 is detected by the sync tip clamp circuit 58, the comparator 59, and the volume 60 to detect the masking signals at the upper and lower ends of the screen. Is switched to the clip level adjustment input side on the b side, and is switched to the a side for other signals.
That is, the luminance signal Y is input to the (+) side of the comparator 59 after being clamped by the sync tip clamp circuit 58 to the synchronization signal front end level which is the waveform peak value. Also,
A DC value whose level has been set in advance by the volume control 60 is input to the (−) side of the comparator 59. The comparator 59 compares the pedestal black level on which the color burst signal is superimposed in the video signal clamped to the (+) side synchronizing signal tip level with the (-) side volume setting value for a certain period in the blanking period. , High “1”, low “0” control signal C
Outputs _W. Taking this situation as an example of the NTSC improved high-definition wide aspect television signal shown in FIG. 10, the pedestal black level is 0IRE in the case of the normal NTSC system (see the pedestal black level in the areas 41 and 43). The pedestal black level of the upper and lower ends 42 of the screen on which the high frequency signal is superimposed is 80 IRE. The pedestal black level in the area 42 in FIG. 10 can be set as appropriate, and is set to 80 IRE as an example.
For this reason, the volume set value connected to the (-) side of the comparator 59 is set to this intermediate value, and whether the signal is a normal NTSC signal during a certain period (period A in FIG. 10) within the horizontal blanking period. It compares and detects whether the signal is a masking signal on which a high-frequency signal is superimposed, and outputs a switching control signal _CW .

As described above, the clipping circuit 57 clips only the superimposed signal in the masking signal in the luminance signal Y which has been contour-compensated (high-frequency emphasized) by the preceding circuit 56. This signal is input to the matrix circuit 64. Another input terminal of the matrix circuit 64 is provided with a color difference signal R-demodulated by the color demodulation circuit 63.
Y, B, Y are input and converted to R, G, B signals, which are then supplied to a cathode ray tube 65 to reproduce a high-definition wide-aspect television signal in which the upper and lower ends of the screen are masked in black.

FIG. 8 is a block diagram of another embodiment of the reproducing apparatus according to the present invention. Similar to the embodiment shown in FIG. 7, when a high-definition wide-aspect television signal is received and reproduced by a receiver of the NTSC system, the reproduction is performed. The noise is prevented from appearing in a blackish region above and below the screen. In this embodiment, the object is achieved by adding a circuit shown by a dotted line in FIG. 8 to an existing NTSC receiver.

In FIG. 8, 71 is an antenna, 72 is a tuner, 73
Is a video intermediate frequency filter, 74 is a video detection circuit, 75 is a switching circuit, 76 is a sync tip clamp circuit, 77 is a sync separation circuit, 78 is a comparator, 79 is a volume, 80 is a blanking signal generator, and 81 is YC separation Circuit, 82 is a color demodulation circuit,
83 is a matrix circuit, and 84 is a CRT for display. The NTSC-improved high-definition wide-aspect television signal transmitted from the transmitting side is received by the antenna 71,
The frequency is converted to an intermediate frequency band by the tuner 72, and the band is limited by the video intermediate frequency filter 73, and then extracted by the video detection circuit 74 as a video baseband signal shown in FIG. This video signal is supplied to the a input terminal of the signal switching circuit 75, the sync tip clamp circuit 76, and the sync separation circuit 77. The blanking signal generated by the blanking signal generator 80 based on the composite synchronization signal output from the synchronization separation circuit 77 is supplied to the b input terminal of the signal switching circuit 75. The switching of the a and b input terminals of the signal switching circuit 75 is appropriately switched by the control signal _CW obtained from the sync tip clamp circuit 76, the comparator 78, and the volume 79. That is, the video signal is input to the (+) side of the comparator 78 after the sync signal, which is the peak value of the waveform, is clamped by the sync tip clamp circuit 76.
In addition, a volume 79 is set in advance on the (−) side of the comparator 78.
The DC value whose level has been set in is input. The comparator 78 compares the pedestal black level on which the color burst signal is superimposed in the video signal clamped to the leading level of the (+) side synchronizing signal with the volume setting value on the (-) side during a blanking period. The control signal _CW of ", low" 0 "is output. Taking this as an example for the high-definition wide-aspect television signal shown in Fig. 10, the normal NTSC
In the case of the system, the pedestal black level is 0IRE (area 41, 4
3) In addition, the upper and lower ends of the screen where the high-frequency signal component is superimposed
The 2 pedestal black level is 80IRE. The area in Fig. 10
The pedestal black level of 42 can be set as appropriate, and is set to 80IRE as an example. For this reason, the comparator (-) side volume setting value is set to this intermediate value, and a normal NTSC signal or a high-frequency signal is superimposed during a certain period (period A in FIG. 10) during the horizontal blanking period. Compare and detect whether the signal is a masking signal.

Accordingly, in the signal switching circuit 75, the control signal _CW allows the signal on the a side to pass through for the signal of the normal NTSC system, and the blanking on the b side for the masking signal on which the high frequency signal component is superimposed. A signal is output.

This output signal is separated into a Y signal and a C signal by a YC separation circuit 81, and the C signal is converted into R, Y, B and Y by a color demodulation circuit 82.
Is demodulated to the color difference signal of The matrix circuit 83 converts the Y, R, Y, B, Y signals into R, G, B signals and supplies them to the cathode ray tube 84 to convert a high-definition wide aspect television signal in which the upper and lower edges of the screen are completely masked. Reproduce.

Effect of Generation Since the present invention is configured as described above, an aspect ratio of 4: 3 or more and a high-definition wide-aspect television signal in which a vertical or horizontal high-frequency signal is superimposed on a masking area at the top and bottom of the screen can be received by the current NTSC receiver. In the case of receiving and reproducing by a device, a vertical or horizontal high-frequency signal superimposed on the masking area is not reproduced, a video without interference can be reproduced, and the quality of a reproduced image can be further improved. When played back with a wide-aspect receiver, a wide-aspect and high-quality wide-aspect image can be played back, and compatibility with a high-definition wide-aspect television transmission system can be enhanced.

In addition, the reproducing apparatus detects a masking signal on which the high-frequency component is superimposed by means for detecting a black level for each scanning line and comparing a detection value of the detecting means with a prescribed pedestal black level (OIRE). And means for clipping a superimposed signal portion in the luminance signal in the masking area, it is possible to reproduce a clear image without obstruction such as unsightly noise in black areas at the top and bottom of the screen. it can.

Also, the reproducing apparatus compares a detection value of the detection means with a prescribed pedestal black level (0IRE) by means of a means for detecting a black level for each scanning line, and outputs a masking signal on which the high frequency component is multiplexed. In the case where the detecting means, the means for generating a blanking signal or a black burst signal, and the means for switching the masking signal to the blanking signal or the black burst signal are similarly unsightly in the black areas at the top and bottom of the screen. A clear image without interference such as noise can be reproduced.

[Brief description of the drawings]

FIG. 1 is a block diagram of an encoder unit according to an embodiment of the present invention, FIGS. 2, 3, 4, and 5 are explanatory diagrams of its operation, and FIG. 6 is another embodiment of the present invention. FIGS. 7 and 8 are block diagrams of still another embodiment of the decoder section of the present invention, FIG. 9 is a block diagram of a conventional encoder section, and FIGS. 10 and 11. The figure is an explanatory diagram of a high definition wide aspect television signal. 3,7 ... scanning line number converter, 4,10 ... position converter, 9 ... frequency shift circuit, 12 ... color burst and reference signal generator, 57 ... clip circuit, 58,76 ... sync Chip circuit, 59,78 ... Comparator, 61,75 ... Switching circuit.

Claims (3)

(57) [Claims] 1. A high-definition wide-aspect television signal transmission system that is compatible with the NTSC color television transmission system and that masks the upper and lower parts of the screen and superimposes a vertical high-frequency signal or a horizontal high-frequency signal on the masking area. in it, the color subcarrier f _SC Ikii phase is inverted every the vertical high frequency signal or horizontal high band signal scanning lines and each frame is "time -
A means for frequency-converting a carrier having a conjugate relationship with the color subcarrier f _SC in the “vertical” two-dimensional frequency domain and superimposing it on the masking area, and a color killer for operating the color burst signal of the masking area on an NTSC receiver. And a means for superimposing the vertical high-frequency signal or the reference signal for horizontal high-frequency signal demodulation on each scanning line of the masking area. 2. A high-definition wide-aspect television which is compatible with the NTSC color television transmission system, masks the top and bottom of the screen, and superimposes a vertical high-frequency component, a horizontal high-frequency component, or an audio signal on the masking area. In a signal transmission type reproducing apparatus, a means for detecting a black level for each scanning line, and a masking signal on which the high frequency component is superimposed by comparing a detection value of the detection means with a prescribed pedestal black level (0IRE) And a means for clipping a superimposed signal portion in the luminance signal in the masking area. 3. A high-definition wide-aspect television that is compatible with the NTSC color television transmission system, masks the top and bottom of the screen, and superimposes a vertical high-frequency component, a horizontal high-frequency component, or an audio signal on the masking area. In a signal transmission type reproducing apparatus, a masking means for detecting a black level for each scanning line, and comparing a detected value of the detecting means with a prescribed pedestal black level (0IRE) to multiplex the high-frequency component. A television signal reproducing apparatus comprising: means for detecting a signal; means for generating a blanking signal or black burst signal; and means for switching the masking signal to a blanking signal or black burst signal.