JPH0779420A - Television reinforce signal system - Google Patents

Abstract

PURPOSE:To eliminate crosstalk of a VT signal and a VH signal by allocating a vertical time resolution reinforce signal VT and a vertical resolution reinforce signal VH at different time frequency areas in a 3dimension frequency area represented by the horizontal, vertical and time signals and multiplexing the VT signal at all times and multiplexing the VH signal when a motion of a picture is small. CONSTITUTION:The frequency allocation of a VH signal and a VT signal, for example, is formed by a vertical frequency nu-time frequency f area. In this case, the VH signal is not modulated and the VT signal is subject to time frequency modulation by a signal of 15Hz and then multiplexed and when the vertical frequency of the VT signal is modulated by a 180-line per height vertical high frequency component 1ph, the signal is multiplexed on 2nd and 4th quadrants shown in figure. Moreover, when the VH signal is subject to time frequency modulation by a signal of 7.5Hz and its reflected frequency of -22.5Hz and the VT signal is subject to time frequency modulation by a signal of 22.5Hz and its reflected frequency of -7.5Hz, the state is shown in the 4th quadrant. The frequency separation at the receiver side is executed without contradiction independently of the presence of the vertical or horizontal frequency modulation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a television enhancement signal system, and more particularly to a vertical time resolution enhancement signal (VT signal) and a vertical resolution enhancement signal (VH signal) while maintaining compatibility with the current television system. The present invention relates to a multiplexing method and a separating method.

[0002]

2. Description of the Related Art A second generation ED which has a wide screen and high image quality while maintaining compatibility with the current television system.
Standardization of the TV system is in progress. As a widening method, the adoption of the letterbox method in which non-image areas are provided above and below the current screen is under consideration, and many methods of transmitting various reinforcing signals for high image quality using this non-image area have been proposed. There is.

As a candidate for the reinforcement signal to be multiplexed in the non-picture part,
A signal (VH signal) for reinforcing the vertical resolution that decreases when the letterbox processing is performed on the transmitting side is mentioned. This signal mainly contains 360-480 lph (lines
vertical height component of (per height) is included.

It is also conceivable to use a progressive scanning type signal source on the transmitting side to newly transmit a scanning line signal which cannot be transmitted due to interlaced scanning as a vertical time resolution reinforcing signal (VT signal). There is. To create this VT signal, SSKF (Symmetric Short Kernel Filter)
Is used (Reference 1: For example, Morita et al .; “Letterbox-based evaluation noise”, Television Technical Report, 16, 7, p.
p.25-32, BCS'92-5 (Jan.1992)).

Since the VH signal has a large image quality improving effect in the still region of the image and the VT signal has a large image improving effect in the moving region, the non-image part having a limited transmission capacity is effectively used, so that in the still region of the image. A method has been proposed in which the VH signal is multiplexed by switching the VT signal in the moving region (Reference 2:
"Television circuit", Japanese Patent Application No. 4-319740).

[0006]

When a main signal and a VT signal are created by SSKF, only the vertical low frequency component (0 to about 240 lph) is transmitted as the main signal, and the VT signal is a component that reinforces the vertical time resolution. And a vertical mid-range component (about 240 to 360 lph) are transmitted (reference 1).

However, in the technique described in Reference Document 2, since the VH signal and the VT signal are exclusively switched and multiplexed, it is impossible to reproduce both at the receiving side at the same time, and the VT signal is not transmitted. There was a problem that the vertical mid-range component was missing in the stationary area.

Therefore, an object of the present invention is to provide a television-enhanced signal system in which a VT signal is always transmitted regardless of the magnitude of motion, and a VH signal can be simultaneously transmitted at least in an area where motion is small.

[0009]

[Means for Solving the Problems]
In the three-dimensional frequency domain represented by vertical ν, time f], the VT signal and the VH signal are arranged in different time-frequency domains, the VT signal is always multiplexed, and the VH signal is multiplexed at least when the motion of the image is small. It can be realized by

[0010]

When the VT signal and the VH signal are multiplexed on different time-frequency regions on the transmitting side, the spread of the time-frequency spectrum is small when the image movement is small. Can be separated without crosstalk.

On the other hand, when there is a large amount of movement, the spectra of the two may spread, and it may be impossible to separate them by overlapping. In this case, the transmitting side stops the VH signal multiplexing and the receiving side stops the VH signal separation,
All the transmitted reinforcement signals are VT signals.

As a result, the VT signal can always be transmitted regardless of the magnitude of the movement, and at least the VH signal can be transmitted at least in the area where the movement is small.

[0013]

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

FIG. 1 shows an example of frequency arrangement of VH signals and VT signals in the present invention in the [vertical frequency ν-time frequency f] region. In the same figure (a), without modulating the VH signal,
The case where the VT signal is time-frequency modulated at 15 Hz and multiplexed is shown. FIGS. 10B and 10C show a case where the VT signal is further subjected to vertical frequency modulation at 180 lph and multiplexed in the second and fourth quadrants. The same figure (d)
The VH signal at 7.5 Hz (and its return -2).
2.5 Hz), the VT signal is time-frequency-modulated at 22.5 Hz (and -7.5 Hz at its return). The VH signal and the VT signal may have the opposite frequency arrangement. Thus, by arranging both in different time-frequency regions, the spread of the time-frequency spectrum is small when the motion of the image is small, regardless of the presence or absence of vertical or horizontal frequency modulation. Both can be separated. On the other hand, when the movement is large, the transmission side stops the multiplexing of the VH signals and the reception side stops the separation of the VH signals, and the transmitted reinforcement signals are all VT signals. The so-called "30" that cannot be detected by the receiving side
Hz motion "(Reference 3: Suzuki et al .; Multiplexing of pseudo-motion signal on transmission side for progressive scan conversion", TV magazine, 42,
9, pp.966-972 (1988)), the spread of the spectrum is small in both the VT signal and the VH signal, as in the case of the stationary state, so that the frequency separation between the two can be performed on the receiving side without contradiction. However, when motion is detected in the progressive scanning mode on the transmission side, "30 Hz motion" can be detected. Therefore, VH signal multiplexing may be stopped in consideration of unstable operation on the reception side due to noise or the like. How to select the time frequency modulation carrier will be described in detail later.

FIG. 2 shows a block diagram of an embodiment of the encoder used in the present invention. In the figure, from the input signal of 480p (the number of effective scanning lines is 480, p is the sequential scanning mode), the main signal generating circuit 1, the VT signal generating circuit 2, and the VH signal generating circuit 3 respectively perform 360i (effective scanning). Main signals MN and V of 360 lines, i represents the interlaced scanning form)
Create T signal and VH signal. The VT signal and the VH signal are modulated by the time-frequency modulation carriers f1 and f2, which will be described later, using the multipliers 4 and 5, respectively. The amplitude of the modulated VH signal is set to 0 by the amplitude variable circuit 6 controlled by the output k of the motion detection circuit 7 in order to prevent the time spectrum from spreading and overlapping with the VT signal. . At this time, binary ON / OFF
However, the reproduced image has less unnaturalness when it is brought closer to 0 in a multivalued (continuous) manner. After the output of the multiplier 4 and the output of the amplitude variable circuit 6 are multiplexed by the adder 8, the process circuit 9 converts 3 to 1 scanning lines (the number of scanning lines is converted from 360 to 120 by horizontal compression multiplexing). , Rearrange scan lines, add predetermined setup values, etc.
The non-picture portion signal MK is used. At this time, horizontal frequency modulation and vertical frequency modulation may be arbitrarily performed. The switch 10 is arranged so that the main signal MN is arranged in the central portion (main image portion) of the current screen, and the non-image portion signal MK and the upper and lower non-image portions of the current screen.
To switch to a transmission signal. The main signal generation circuit 1, the VT signal generation circuit 2, and the VH signal generation circuit 3 can use the configurations described in the above-mentioned References 1 and 2 as they are, and therefore are not particularly shown. The motion detection circuit 7 can use a general frame difference detection configuration (for example, the configuration described in Reference Document 2) as it is, and is not particularly illustrated. Further, although the motion is detected from the input signal in the figure, the motion may be detected from the main signal MN, the VT signal, the VH signal and the like. Also, V
It is also possible to detect only movements in the same band as the transmission band of the T signal and VH signal (horizontal about 1.4 MHz). Process circuit 9
Is easily illustrated in the related art, such as the configuration described in Reference Document 2, and thus is not illustrated. The setup value may be a black level (0 value), but may be a positive value for facilitating synchronization separation on the receiving side, and may be a negative value so that the non-picture area signal MK is not conspicuous in the current receiver. Good.

FIG. 3 shows a block diagram of an embodiment of the decoder used in the present invention. In the figure, the transmitted signal is first transmitted by the switcher 11 to the main signal MN and the non-picture area signal MK.
To separate. The non-image area signal MK is subjected to reverse processing of the encoder process circuit 9, such as setup value removal, scan line rearrangement, and 1 → 3 conversion by the reverse process circuit 12. At this time, if horizontal or vertical frequency modulation is performed by the encoder, demodulation is also performed. From this signal, the time-frequency filter 13 extracts the component in the frequency domain in which the VH signal is multiplexed, and outputs k from the motion detection circuit 15.
The amplitude variable circuit 14 controlled by outputs the amplitude 1 as the VH signal as it is when the motion is small, and outputs it as the amplitude 0 when the motion is large. At this time, 2
The value may be turned ON / OFF in a numerical manner, but may be brought close to 0 in a multivalued (continuous) manner. By subtracting this signal from the output of the inverse process circuit 12 using a subtractor 16, the VT
Separate the signals. The separated VT signal and VH signal are demodulated by time-frequency demodulation carriers f1 and f2 using multipliers 17 and 18, respectively. The combining circuit 19 converts the main signal MN, the VT signal, and the VH signal from the 360i form to the 480p form and combines them into an output signal. The inverse process circuit 12 can be easily realized by a conventional technique such as the configuration described in the reference document 2, and therefore is not particularly illustrated. Time frequency filter 13
Can be easily realized by a sum / difference calculation between frames (525H: 1H is one horizontal scanning period), and is not particularly shown.

The motion detection circuit 15 has a general frame difference detection configuration (for example, the configuration described in Reference 2),
Configuration based on 2-frame difference detection (for example, Reference 4: Kudo et al .; “NT based on 2-frame difference and cyclic motion domain interpolation”
"SC signal motion detection", TV full size, 13-1 (1987)) can be used as is, so it is not shown in the figure. Also, in the figure, motion detection is performed from the transmission signal, but the main signal is used. The motion may be detected from either one of the MN and the non-picture part signal MK, or they may be separately detected from the motion and then combined, and the transmission band of the VT signal and the VH signal (horizontal about 1. 4 MHz) may be detected only in the same band.
60i → 360p conversion), scanning line conversion (360p → 48)
0p conversion), a vertical filter, and the like. For example, the configurations described in References 1 and 2 described above can be used as they are, and thus are not particularly illustrated.

FIG. 4 shows an example of the time-frequency modulation / demodulation carriers f1 and f2 used in the present invention. In principle,
Anything may be used as long as the time frequencies of f1 and f2 are different, but the frame frequency of the current television system is 30 Hz.
Therefore, crosstalk is minimized when there is a difference of 15 Hz between f1 and f2. Also, the carrier phase of 15 Hz is the polarity reversal between frames, which is 7.5 Hz and 22.5
Since Hz can be expressed by polarity inversion between two frames,
Modulation / demodulation processing becomes easy. Further, the 0 Hz modulation / demodulation process may be omitted. In the case of 7.5 Hz and 22.5 Hz, the non-image part signal MK is temporarily modulated at 7.5 Hz by the decoder, the VT signal is set to 0 Hz (or 15 Hz), and the VH signal is set to 15 Hz (or 0 Hz). If the separation process is performed, the time-frequency filter can be configured by the sum / difference calculation between frames, which can be simplified.

In the present invention, since it is sufficient that the VT signal and the VH signal are arranged differently in the time-frequency domain, only one of them may be time-frequency modulated.
Further, the modulation of the horizontal and vertical frequencies is arbitrary. In particular, if modulation is performed at a horizontal frequency of 3.58 MHz and is inverted so that scanning lines and frames are inverted (that is, as shown in FIG. 1b), it is the same as the modulation by the color subcarrier. It can be shared with a modem circuit. Further, although different horizontal / vertical modulation frequencies may be used for the VT signal and the VH signal, if the same frequency is used, modulation / demodulation can be performed at once for the MK signal that is a combination of the VT signal and the VH signal. The circuit scale can be reduced.

Further, it is obvious that the present invention can be used not only for transmitting signals but also for storing (recording).

[0021]

According to the present invention, the VT signal can always be transmitted regardless of the magnitude of the movement, and at least the VH signal can be transmitted at least in the area where the movement is small.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an example of frequency allocation of VH signals and VT signals in the present invention.

FIG. 2 is a configuration diagram of an embodiment of an encoder used in the present invention.

FIG. 3 is a configuration diagram of an embodiment of a decoder used in the present invention.

FIG. 4 is an explanatory diagram of a carrier for time-frequency modulation / demodulation used in the present invention.

[Explanation of symbols]

1 ... Main signal creation circuit; 2 ... VT signal creation circuit; 3 ... VH signal creation circuit; 4,5,17,18 ... Multiplier; 6,14 ... Amplitude variable circuit; 7,15 ... Motion adaptation circuit; 8 ... Adder; 9 ... Process circuit; 10, 11 ... Switcher; 12 ... Inverse process circuit; 13 ... Time-frequency filter; 16
… Subtractor; 19… Combining circuit.

Front page continued (72) Inventor, Hideshi Kinomata, 14-2 Nibancho, Chiyoda-ku, Tokyo Within Nippon Television Broadcasting Network Co., Ltd. (72) Masayuki Ishida, 14th Nibancho, Chiyoda-ku, Tokyo Nippon Television Broadcasting Co., Ltd. Within

Claims (6)

[Claims] 1. In a television augmentation signal system for transmitting at least two or more augmentation signals while maintaining compatibility with the existing television system, the first augmentation signal and the second augmentation signal are different from each other in time-frequency regions. A television-enhanced signal system characterized in that it is arranged and transmitted. 2. The television reinforcing signal system according to claim 1, wherein the first reinforcing signal is always multiplexed, and the second reinforcing signal controls a multiplexing level according to the movement of an image. 3. The television according to claim 1, wherein the difference between the center time frequencies of the first and second reinforcement signals arranged in different time frequency regions is 1/2 of the frame frequency. John reinforcement signal system. 4. The television reinforcing signal system according to claim 1, wherein the first reinforcing signal is a signal (VT signal) for reinforcing vertical time resolution. 5. The television reinforcing signal system according to claim 1, 2, or 3, wherein the second reinforcing signal is a signal (VH signal) for reinforcing vertical resolution. 6. The method according to claim 1, 2, 3, 4, 5,
And a second augmentation signal, which is arranged and transmitted in an area displayed on the upper and lower parts of the current television screen and is transmitted.