JP2692157B2 - Television signal processing method and television signal processing device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a television signal processing method and a television signal processing method in which information for improving the image quality of current television broadcasting is extracted and transmitted at the transmitting side and reproduced at the receiving side. The present invention relates to a signal processing device.

Conventional Technology Japan's current NTSC (National Television System Committee)
mittee)] method for color television broadcasting in Showa 35
More than 25 years have passed since the year began. In the meantime, various new television schemes have been proposed along with the demand for high-definition screens and the improvement in performance of television receivers. In addition, the content of the service program itself is changing from a mere studio program or a relay program to a program having a higher image quality and a more realistic image, such as a cinema-size movie broadcast.

Current broadcasts have specifications of 525 scanning lines, 2: 1 interlace scanning, luminance signal bandwidth 4.2MHz, aspect ratio 4: 3 (for example, literature: Broadcasting Technology Sosho Color Television, edited by Japan Broadcasting Corporation, published by Nippon Broadcasting Corporation). The association, 1961, see), but is a television that is compatible with the current television system under such a background and can multiplex transmit a large amount of information within the band defined by the standard. Signal processing methods have been proposed.

One conventional example according to the present invention will be described below with reference to the drawings.

First, a television signal processing method using quadrature modulation of a video carrier (see Japanese Patent Laid-Open No. 61-164915) will be described. FIG. 8 is a spectrum diagram showing a television signal processing method on the transmitting side. FIG. 8 (a) is a spectrum diagram of a television signal that has been subjected to vestigial sideband amplitude modulation in the current television system. Here, the case where the lower sideband of the image carrier P ₁ is the vestigial sideband is shown. Figure 8 (b) in another multiplex signal from the television signal shown in Figure 8 (a), returning the video carrier P ₁ and the same frequency at and phase + 90 ° or -90 ° different carrier P ₂ The vestigial sideband amplitude modulation is performed so as to remove the carrier wave P _{2 in the} line period, and the band is limited by a filter having a characteristic opposite to the frequency characteristic of the video intermediate frequency filter described later. A signal obtained by multiplexing the signal shown in FIG. 8 (b) with the television signal shown in FIG. 8 (a) is shown in FIG. 8 (c), which is a television signal synthesized by the conventional example shown here.

Next, a television signal processing method on the receiving side for a television signal synthesized by the above method will be described with reference to FIG. In the following, the case of terrestrial broadcasting is taken as an example. The signal received on the receiving side is frequency-converted into an intermediate frequency band and band-limited by the video intermediate frequency filter.
Reproduced from the band-limited signal carrier wave I _1, synchronously detected in a video detector the band-limited signal at the carrier I _1, to obtain a video baseband signal. Here, the frequency characteristics of the video intermediate frequency filter will be described. The frequency characteristic is shown in FIG. 9 (a). That amplitude is 6dB attenuation at the picture carrier I _1, and has a Nyquist filter characteristic having a substantially odd symmetrical amplitude characteristic with respect to the picture carrier I _1. On the other hand, as shown in FIG. 8 (b), if the multiplexed signal is band-limited by a filter having a characteristic opposite to the frequency characteristic of the video intermediate frequency filter of the receiver, the shaded area in FIG. 9 (a) is obtained. The multiple signal component of is almost a double sideband. A vector display of this is shown in FIG. 9 (b).
become that way. Here, I ₁ is a video carrier of a video baseband signal, and I ₂ is a carrier of a multiplexed signal, which is a carrier having the same frequency as I ₁ but different in phase by + 90 ° or −90 °.
Since the video baseband signal is a vestigial sideband when the carrier I ₁ is considered as the center, upper and lower sidebands are vectors a _U and a _L , which are decomposed into orthogonal vectors to be vectors a ₁ and a _2. . Also, since the multiplexed signal has almost double sidebands, if the upper and lower sidebands are vector b _U and vector b _L , the combined vector thereof is b ₂ .
There are only components that are orthogonal to the vector I ₁ . That is, when the coherent detection is performed on the carrier wave I ₁ , the orthogonal distortion due to the vector a ₂ and the vector b ₂ components does not occur, and the interference by the multiple signal to the current television receiver performing the video coherent detection does not occur in principle.

Next, a method of demodulating multiple signals on the receiving side for a television signal synthesized by the above method will be described. The signal in the video intermediate frequency band, which is the output of the tuner, is
As shown in FIG. 6A, the video baseband signal is band-passed by the filter so that it becomes a double sideband. A vector display of this is as shown in FIG. 10 (b). The multiplexed signal is carrier I
Considering ₂ as the center, there are residual sidebands, so the upper and lower sidebands become vectors b _U and b _L , and when decomposed into orthogonal vectors, they become vectors b ₁ and b ₂ . Further, since the video baseband signal becomes almost double-sideband by the filter, if the upper and lower sidebands are vector a _U and vector a _L , their combined vector becomes a ₁ , and only the component orthogonal to vector I ₂ is obtained. . That is, when the carrier wave I ₂ is synchronously detected, orthogonal distortion due to the vector a ₁ and vector b ₁ components does not occur, and only the multiple signal component can be demodulated.

It is considered that the above-described television signal processing method transmits a high-frequency component of a luminance signal as a multiplex signal or both-end images (side panels) of a screen having a wide aspect ratio.

Next, another conventional example related to the present invention will be described with reference to the drawings.

FIG. 12 shows an NTSC television signal on a two-dimensional plane having a time frequency f and a vertical frequency ν.
The color signal C exists in the second and fourth quadrants due to the phase relationship of the color subcarrier f _SC . First and third vacant here
It is characterized in that the high-frequency component of the luminance signal is multiplexed in the quadrant, and the receiving side performs arithmetic processing between the fields to separate the color signal and the multiplexed high-frequency component to improve the horizontal resolution. (See Japanese Patent Laid-Open No. 59-171387) It is also considered to transmit an image at both ends (side panel) of a screen having a wide aspect ratio instead of the high frequency component of the luminance signal as a multiplex signal. In this case, in order to remove crosstalk between the multiplexed signal and the original NTSC signal, a part of the original signal in the first and third quadrants of the two-dimensional plane shown in FIG. 12 is deleted in advance. Even if the signal in this part is deleted, the diagonal dynamic resolution of the original signal is slightly degraded. Furthermore, in the case of multiplexing in the first and third quadrants,
A method has been proposed in which 3.1 MHz is selected and two types of multiplexed signals are double-sideband modulated (see 1988 International Consumer Electronics Conference [International Conference Consumer Electronics] Proceedings, pp. 140-141).

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention As described above, in the current television broadcasting, the signal band is limited by the standard, and it is not easy to add some multiplex information. For example, a television signal processing method as described above has been proposed, but the vertical resolution of a moving image has not been improved at all from the viewpoint of interference with the current television receiver.

The present invention has been made in view of the above problems, and is compatible with the current television system and is a television signal processing method capable of multiplex-transmitting a large amount of information within the band defined by the standard, and the current television It is an object of the present invention to provide a television signal processing method and a television signal processing method capable of effectively improving the vertical resolution of a moving image of a signal.

Means for Solving the Problems In order to achieve the above object, a television signal processing method of the present invention, the information that the progressive scanning television signal has,
Information transmitted by the interlaced scanning television signal, divided into information of the information having the progressive scanning television signal and information transmitted by the interlaced scanning television signal,
The information transmitted by the interlaced scanning television signal is NTSC.
The information of the difference between the information carried by the progressive scanning television signal and the information transmitted by the interlaced scanning television signal is the signal of the system, and the information on the two-dimensional plane of the time frequency and the vertical frequency of the signal of the NTSC system is used. The first and third quadrants are processed so that they are multiplexed and transmitted, and the television signal processing device receives the progressive scanning television signal as an input, and is a first signal composed of signals in time series of the progressive scanning television signal. A first delay unit group having at least one horizontal scanning period as a delay unit for obtaining a group; a first coefficient unit group for multiplying the obtained first signal group by a coefficient; A first adder for adding a signal group multiplied by a coefficient by the coefficient unit group of
A second time-series signal of the output of the first adder,
Second delayer group having at least one horizontal scanning period as a delay unit for obtaining the signal group of
A second coefficient multiplier group for multiplying the signal group of No. 1 by a coefficient, a signal group multiplied by the coefficient by the second coefficient multiplier group, and a signal required by the processing target of the first signal group are added. It has a structure provided with a 2nd adder and a circuit which removes an unnecessary signal among the output signals of the 1st adder and the 2nd adder.

Advantageous Effects of the Invention According to the present invention, by the method and apparatus described above, information effective for improving the image quality of a television signal is transmitted and reproduced at the receiving side, so that a better image, particularly an image with improved vertical resolution in a moving image is obtained. Can be obtained. Further, the current television receiver can receive the image of the conventional television broadcast without any trouble.

Embodiment Hereinafter, a television signal processing method and a television signal processing device according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a two-dimensional plan view of a time frequency and a vertical frequency showing a television signal processing method according to an embodiment of the present invention. In the conventional NTSC system, only information in a region surrounded by a rectangle having vertices 2, 4, 6, and 8 (hereinafter referred to as region Q) can be transmitted without aliasing distortion. This is because the NTSC system transmits images by 2: 1 (60 fields / 30 frames) interlaced scanning. For example, 1:
1 (60 fields / 60 frames) progressive scan image is the first
It is composed of information of a region surrounded by a quadrangle having vertices 1, 3, 5, 7 in the figure (hereinafter referred to as region P). When an image composed of the information in the area P is to be transmitted by interlaced scanning, it is limited to the area Q in advance in order to eliminate the aliasing distortion in the transmission system, and then the scanning line is thinned to every two lines. To transmit. That is, in order to obtain the information of the area P on the receiving side,
In addition to the information of the area Q transmitted by the same transmission line as before,
The information of the difference (P-Q) between the area P and the area Q, that is, the information of the area shaded in FIG. It is sufficient to reproduce the information in the area P from. A television signal processing method therefor will be described below.

FIG. 2 schematically shows a scanning line structure of a progressive scanning television signal. For the scanning line f, from the peripheral scanning lines b, e, x, i, The scanning line f having the information of the area P is converted into the scanning line F having the information of the area Q by the arithmetic processing as described above. Such an operation is also applied to the scanning lines c, j, g, etc. to make the scanning lines C, J, G, and then the unnecessary scanning lines are thinned out to obtain a 2: 1 ratio as shown in FIG. 3 (a). (60 fields / 30 frames) Interlaced scanning signal. Next, in order to extract the information of the area D, the scan lines C, F, G, J which have been arithmetically processed by the equation for the scan line x.
From Is calculated. The same operation is performed on scan lines a, b, d, e, h, i, k, l
As shown in Fig. 3 (b), the scan lines A, B, D, E, H, I, K, L are applied to the lines, and unnecessary scan lines are thinned out.
2: 1 (60 fields / 30 frames) Interlaced scanning signal. Scan lines represented by scan lines C, F, G, and J are transmitted by a conventional transmission path, and scan lines represented by scan lines A, B, D, E, H, I, K, L, and X are transmitted. By transmitting via another transmission path, all the information in the area P has been transmitted. On the receiving side, first the scan line x
Scan lines X, C, F, G, J to reproduce The following arithmetic processing is performed. From the scan lines b, e, x, i and scan line F reproduced by the same arithmetic processing The scanning line f is reproduced by the following calculation. By similar processing, the scanning lines represented by the scanning lines f, c, g, j are reproduced. Scan line a obtained by repeating the above process,
By combining b, d, e, h, i, k, l, x and c, f, g, j and converting to progressive scanning, all the images having the information of the original area P are completely reproduced. Will be.

FIG. 4 is a television signal processing in which a video signal is subjected to the operation of the above formula to obtain a signal that can be transmitted on a conventional transmission line without aliasing distortion and a signal having area D information from a progressive scanning television signal. It is the block diagram which showed one Example of the apparatus. The progressive scan television signal input to the input terminal 11 is a 524H delay device 12, a 1H delay device 14, and a 1H delay device 1.
6, 524H delay device 18 (1H corresponds to one horizontal scanning period) is provided to the first delay device group formed by series connection. As a result, the signals (first signal group) of the scanning lines represented by h, k, g, d, x shown in FIG. 2 are simultaneously obtained at the terminals 11, 13, 15, 17, 19. For these h, k, g, d, x, coefficient units 20, 21, 22, 2
Coefficients 1/8, 1/8, 1 by 3 and 24 (first coefficient unit group)
The signals multiplied by / 2, 1/8, 1/8 are all added by the first adder 25 to obtain a signal having information of the area Q represented by the scanning line G. The interlaced scanning converter 38 removes unnecessary scanning lines from the signal represented by the scanning line G, converts it from sequential scanning to interlaced scanning, and outputs it to the output terminal 40. On the other hand, the signal represented by the scanning line G is input to the input terminal 26 of the second delay group consisting of the 524H delay unit 27, the 2H delay unit 29, and the 524H delay unit 31 connected in series, and the second Signal group G, J, C, F
Are simultaneously available at terminals 26, 28, 30, 32. These are processed by the coefficient units 33, 34, 35, 36 (second coefficient unit group) multiplied by the coefficients -1/4, -1/4, -1/4, -1/4, respectively. By adding the required signal x and the second adder 37, a signal having the information of the area D represented by the scanning line X can be obtained. The interlaced scanning converter 39 removes unnecessary scanning lines from the signal represented by the scanning line X, converts the signal from sequential scanning to interlace, and outputs the signal to the output terminal 41. FIG. 5 differs from FIG. 4 in that the progressive scanning signal is converted into the interlaced scanning signal and then arithmetic processing is performed. In the block diagram of FIG. 5, since the scanning lines have already been thinned, the delay times of the delay units are changed to 524H → 262H and 2H → 1H, respectively.

FIG. 6 shows the receiving side which reproduces the signal having the information of the area P represented by the scanning lines g and x from the signal represented by the scanning lines G and X by performing the calculation of the equation. 2 is a block diagram showing an example of a television signal processing device in FIG. The interlaced scanning signal is input to the input terminal 101 at the input end of a delay group consisting of a 262H delay unit 103, a 1H delay unit 105, and a 262 delay unit 107 connected in series. As a result, the terminals 101, 104, 106 and 108 are shown in FIG. 3 (a).
The signals of the scanning lines represented by G, J, C and F are obtained at the same time.
These G, J, C, and F are multiplied by coefficients 1/4, 1/4, 1/4, and 1/4 by coefficient multipliers 109, 110, 111, and 112, respectively, and the scanning line X input to the input terminal 102 is applied. All the signals having the information of the difference between the representative progressive scanning information and the interlaced scanning information are added by the adder 113, and the signal having the information of the area P represented by x is obtained at the terminal 127. The signal represented by this x is 2
The 62H delay device 115, the 1H delay device 117, and the 262H delay device 119 are input to the input terminal 114 of another delay device group that is configured in series, and x, i, b, and e are simultaneously obtained at the terminals 114, 116, 118, and 120. These are multiplied by coefficients −1/4, −1/4, −1/4, −1/4 by the coefficient units 122, 123, 124, 125, respectively, and the coefficient F 121 is applied by the coefficient unit 121 to the required signal F to be processed. A signal having the information of the area P represented by f is obtained at the terminal 128 by adding the multiplied signal to the adder 126. The signals represented by x and f obtained at the terminals 127 and 128 are converted into progressive scan by the progressive scan converter 129 and output to the output terminal 130.

The transmission path for transmitting a signal having the information of the area D extracted by the method described above is, for example, another transmission path having the same capacity as the transmission path for transmitting the conventional television signal. You may use. In addition, it is also possible to use some kind of band compression technique to transmit using a transmission line having a smaller capacity than before. In addition, by using the transmission by the above-mentioned quadrature modulation of the conventional example, about 1 MHz of the signal having the information of the area D is used.
A method of transmitting the following bands can be considered. Also, about 2MHz
The following low frequencies are explained as a conventional example:
A method of multiplexing and transmitting in a quadrant can be considered. In this case, the transmission area of the f, ν plane of FIG. 12 is limited, so the band is limited to the areas shown in FIGS. 11 (a), (b), (c), etc. A subcarrier suitable as information for separating the information of the area Q and the area D by performing signal processing and multiplexing the information of the area D, that is, the information in the shaded areas in FIGS. 11 (a), (b), and (c). Using f, ν in Fig. 12
Transmission becomes possible by inserting in the first and third quadrants of the plane. As a matter of course, after the appropriate band limitation is added to the information in the shaded area shown in FIGS. 11 (a), (b), and (c), two types of multiplexed information are obtained by the double sideband modulation described above as a conventional example. Can be transmitted as one of the above.

On the other hand, as described as the conventional example, both end images of the screen having a wide aspect ratio instead of the high frequency component of the luminance signal as the multiplex signal transmitted in the first and third quadrants of the two-dimensional plane shown in FIG. 12 ( When transmitting a side panel), in order to remove crosstalk between the multiplexed signal and the original NTSC signal,
A method of previously deleting a part of the original signal in the first and third quadrants of the two-dimensional plane shown in FIG. 12 has been considered. In this method, as shown in Fig. 7 for the band of 1.5MHz to 4.2MHz of the signal, The diagonal dynamic resolution is deleted from the information of the area Q in FIG. here The original Y ₁ and Y ₂ can be reproduced by transmitting X obtained by the following operation and performing the following operation on the receiving side: Y ₁ = Z ₁ + X ... Y ₂ = Z ₁ -X.
As described above, the band of X is required to be a band of about 2.7 MHz from 1.5 MHz to 4.2 MHz, but for the information of two scanning lines Z ₁ and Z ₂ , information for one scanning line X is required. Information can reproduce Y ₁ and Y ₂ . Of the information of 1.5 MHz or more of X, X ₁ having the information of 1.5 MHz to 2.5 MHz and X ₂ having the information of 2.5 MHz to 3.5 MHz, respectively, of the video carrier shown as the conventional example for Z ₁ and Z ₂ . If the signal is transmitted by the multiplex transmission method using quadrature modulation, the receiving side reproduces Y ₁ and Y ₂ from Z ₁ and Z ₂ and X ₁ and X ₂ , so that the deterioration of the diagonal dynamic resolution is caused by the horizontal frequency of 3.5 MHz to 4.2 MHz. It is possible to suppress only a small part of MHz.

EFFECTS OF THE INVENTION As is apparent from the above description, according to the present invention, it is possible to reproduce an image with good vertical resolution of a moving image obtained by using a progressive scanning camera or the like on the receiving side, and to reproduce a conventional television signal. It is possible to improve the image of. Also,
The conventional receiver can reproduce the image as in the conventional case, and is effective from the viewpoint of compatibility with the conventional television signal transmission system.

[Brief description of the drawings]

FIG. 1 is a two-dimensional plan view of a television signal for explaining an embodiment of the present invention, FIG. 2 is a schematic diagram showing a scanning line structure of a progressive scanning television signal, and FIG. First
FIG. 4B is a schematic diagram showing the scanning line structure of a signal having information other than the shaded area in the figure, and FIG. 3B is a schematic diagram showing the scanning line structure of a signal having information in the shaded area of FIG. Figure, Figure 5, Figure 6
FIG. 8 is a block diagram of an embodiment of a television signal processing device of the present invention, FIG. 7 is a schematic diagram showing a television signal processing method of a conventional example, and FIG. 8 (a) is a residual sideband in a current television system. FIG. 8B is a spectrum diagram of the amplitude-modulated television signal, FIG. 8B is a spectrum diagram in which band modulation is performed by a signal different from the signal shown in FIG. 8A, and FIG. FIG. 8B is a spectrum diagram in which the signal shown in FIG. 8B is multiplexed with the signal shown in FIG. 8A, and FIGS. 9A and 9B are spectra at the time of synchronous detection of the current television receiver. Figures and vector diagrams, Figure 10 (a), Figure 10 (b)
Is the spectrum diagram and vector diagram when demodulating multiple signals,
(A), (b) and (c) are two-dimensional plan views showing the characteristics of band components in one embodiment of the present invention, and FIG. 12 is a two-dimensional plan view for explaining a conventional example. 12,14,16,18,27,29,31,55,57,59,68,70,72,103,105,10
7,115,117,119 …… Delay device, 20,21,22,23,24,33,34,35,3
6,61,62,63,64,65,74,75,76,77,109,110,111,112,121,1
22,123,124,125 …… Coefficient unit, 25,37,66,78,113,126 ……
Adder, 38, 39, 52, 53, 129 ... Scan converter.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Hideyo Kamihata 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Nobuo Abe 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. In the company

Claims (6)

(57) [Claims] 1. Information which a progressive scanning television signal has,
Information transmitted by the interlaced scanning television signal, divided into information of the information having the progressive scanning television signal and information transmitted by the interlaced scanning television signal,
The information transmitted by the interlaced scanning television signal is NTSC.
The information of the difference between the information carried by the progressive scanning television signal and the information transmitted by the interlaced scanning television signal is the signal of the system, and the information on the two-dimensional plane of the time frequency and the vertical frequency of the signal of the NTSC system is used. Television signal processing method for multiplexing and transmitting in the first and third quadrants. 2. An interlaced scanning television signal obtained by obtaining information to be transmitted by an interlaced scanning television signal from a signal on one scanning line of a progressive scanning television signal and a signal on a scanning line around the one scanning line. From the signal on one scanning line of the signal having information to be transmitted in the and the progressive scanning television signal, the information of the difference between the information having the progressive scanning television signal and the information to be transmitted by the interlaced scanning television signal, Television signal processing method to be obtained. 3. Information transmitted by an interlaced scanning television signal among information possessed by a progressive scanning television signal,
A television signal processing method for reproducing information included in a progressive scanning television signal from information on a difference between information included in the progressive scanning television signal and information transmitted as the interlaced scanning television signal. 4. A delay unit is at least one horizontal scanning period for inputting a progressive scanning television signal and obtaining a first signal group consisting of time-series signals of the progressive scanning television signal. A first delay unit group, a first coefficient unit group that multiplies the obtained first signal group by a coefficient, and a first coefficient unit group that multiplies the signal group by which the coefficient has been multiplied by the first coefficient unit group. At least one for obtaining a second signal group consisting of an adder and a time-series signal of the output of the first adder
A second delay unit group having one horizontal scanning period as a delay unit, a second coefficient unit group for multiplying the obtained second signal group by a coefficient, and a coefficient by the second coefficient unit group. A second adder for adding the multiplied signal group and a signal required by the processing target of the first signal group; and output signals of the first adder and the second adder A television signal processing device comprising: a circuit for removing unnecessary signals. 5. A first signal having a television signal obtained by the television signal processing method according to claim 1 as an input and having the information transmitted by an interlaced scanning television signal as the input signal. A circuit for separating into a second signal having information of a difference between the information carried by the progressive scanning television signal and the information transmitted by the interlaced scanning television signal, and a signal in time series of the first signal. A first delay group having at least one horizontal scanning period as a delay unit for obtaining a first signal group consisting of: and a first coefficient multiplier for multiplying the obtained first signal group by a coefficient. A group, a second coefficient multiplier for multiplying the second signal by a coefficient, and a first adder for adding the signal coefficient multiplied by the first coefficient multiplier group and the second coefficient multiplier , From the signal on the time series of the output of the first adder That a second delay unit group to at least one of the one horizontal scanning period delay unit for obtaining a second signal group, a second multiplying coefficient to the obtained second signal group
And a second adder for adding the signal group multiplied by the coefficient by the second coefficient unit group and the signal required by the processing target in the first signal group. A television signal processing device characterized by the above. 6. A first signal having information transmitted by an interlaced scanning television signal, information of a difference between information possessed by a progressive scanning television signal and information transmitted by the interlaced scanning television signal. The second signal having
A first delayer group having at least one horizontal scanning period as a delay unit for obtaining a first signal group composed of signals on a time series of the signal, and the obtained first signal group. A first coefficient multiplier group for multiplying a coefficient, a first adder for adding the signal group multiplied by the coefficient by the first coefficient multiplier group and the second signal, and an output of the first adder A second delay group having at least one horizontal scanning period as a delay unit for obtaining a second signal group composed of signals on the time series, and a coefficient for the obtained second signal group. A second coefficient multiplier group for multiplying, a second adder for adding the signal group multiplied by the coefficient by the second coefficient multiplier group, and the signal required by the processing target among the first signal group A circuit for synthesizing output signals of the first adder and the second adder. Vision signal processing apparatus.