JPH03207188A - Moving image signal transmission system - Google Patents

Abstract

PURPOSE:To obtain an image with high definition by removing a signal component in a frequency area, and modulating and multiplexing a horizontal or vertical high frequency component at the free area. CONSTITUTION:A horizontal band dividing circuit 20 divides a moving image signal 50 into a horizontal low frequency component 110, a horizontal intermediate frequency component 111, and a horizontal high frequency component 112. The output signal 116 of a filter circuit 5 is divided by a horizontal band dividing circuit 21 equally into a 1st component 117 and a 2nd component 118 with the horizontal frequency components and they are shifted in frequency to become a 1st modulated signal 119 and a 2nd modulated signal 120. The horizontal intermediate component 111 has its signal component by the signal band of the 1st modulated signal 119 and 2nd modulated signal 120 through a filter circuit 4 to become a band-limited horizontal intermediate frequency component 113. After the band limitation and modulation processing, an addition signal 115 of interlaced scans, the 1st modulated signal 119, and 2nd modulated signal 120 are added and sent as a frequency multiplex signal to a reception side. Consequently, the signal with high definition can be transmitted.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a moving image signal transmission system or recording system.

(Prior Art) A method of transmitting a moving image signal by interlacing scanning has been conventionally used as a method of transmitting a television signal. The transmission band of the signal in the case of interlaced scanning is specified in the Journal of the Television Society V0/. 43, No. 5 1 Small feature/EDTV method, 2. Basic technology for image quality improvement J (Reference 1)
is shown. That is, the progressive scanning image signal is 11 o in the horizontal direction and y in the vertical direction. , f in the time direction. If the signal band (transmittable band) has a frequency band of , the signal band (transmittable band) becomes a rectangular parallelepiped shown by the dashed line in FIG. 11(a). If this progressive scanning signal is interlaced scanned, signal components in which both the temporal frequency and the vertical frequency are in the high range cannot be transmitted, as shown by the straight line in FIG. 2(a). Furthermore, in current NTSC receivers, it is a vertical high frequency component. =52572 causes flicker, so it is generally said that it is necessary to limit the signal band to a signal band of v1:525 x 3/8 or less, as shown in FIG. 11(b).

Recently, a method has been proposed in which high-definition information of a luminance signal is multiplexed and transmitted on the current color television signal. As a proposal method, for example, the Television Society Journal V0
/． 39, No. 1O r fully compatible E
There is a system described in DTV Signal System (Part 1, Part 2) J (Reference 2). In other words, with this method, the current NTS
The C television system is a two-dimensional vertical and temporal frequency space (
Considering v, D, color signals are multiplexed (v, f
) = (525/4, -15), (-52574
, 15) is the conjugate position (v, f
) = (525/4.15), (-525/4,
-15) and multiplexes high-definition information in the horizontal direction (however, the horizontal frequency band is 2.1MHz to 4.2MHz).
z).

(Problems to be Solved by the Invention) In the above-described conventional technology, it is difficult to ensure a sufficiently wide signal band that can be transmitted when transmitting a luminance signal. That is,
The horizontal signal band that can be transmitted using the technique described using Document 1 is limited to the occupied signal band on the transmission path, and there is a drawback that vertical high frequency components cannot be transmitted. Further, in the method described using Reference 2, since color signals are also transmitted, there is a limit to the signal band that can be transmitted as a luminance signal, and furthermore, vertical high frequency components are not multiplexed.

SUMMARY OF THE INVENTION An object of the present invention is to alleviate or eliminate the drawbacks of the conventional method and to provide a moving image signal transmission method in which the luminance signal of a moving image signal is band-compressed and transmitted.

(Means for Solving the Problems) The moving image signal transmission system of the first invention has 9 vertical directions. and f in the time direction. In a video signal transmission method that interlaces and transmits a video signal with a frequency band of The horizontal high-frequency component is band-limited by a low-pass filter in the vertical/time-frequency space to obtain a band-limited horizontal high-frequency component, and the band-limited horizontal high-frequency component is frequency-divided. 1st
The first component is frequency-converted in the horizontal direction so that it has the same frequency band as the horizontal intermediate component, and +7 in the vertical direction. l2 and a signal whose frequency is shifted by +f0/2 in the time direction as a first modulation signal, and the second component is frequency-converted in the horizontal direction so that it has the same frequency band as the horizontal intermediate component, and in the vertical direction -, . l2 and +f in the time direction. The signal frequency-shifted by l2 is used as the second modulation signal, and the horizontal intermediate component is filtered in the vertical time-frequency space (ν, f) to generate (ν, f)=(±vo/2, ±f0/2). ) of 4
A signal component centered around a point is removed to obtain a band-limited horizontal intermediate component, and a frequency multiplexed signal obtained by adding the horizontal low-frequency component, the band-limited horizontal intermediate component, the first modulation signal, and the second modulation signal is transmitted. It is something to do.

Further, in the moving image signal transmission system of the second invention, V in the vertical direction. In a video signal transmission method in which a video signal having a frequency band f0 in the time direction is interlaced scanned and transmitted, the video signal has a high frequency band in the vertical direction of the image and a low frequency band in the temporal direction. Extract two components, a certain vertical high frequency component and a vertical low frequency component that is a vertical low frequency component of the image, and convert the vertical low frequency component into a horizontal low frequency component and a horizontal high frequency component according to the horizontal frequency of the image. The horizontal high-frequency component is divided into two components, and the vertical time-frequency space (v, f
) by filtering (ν, f) = (Siya./2, ±f
0l2) are removed to obtain a band-limited horizontal high-frequency component, and the vertical high-frequency component is frequency-divided into two components, a first component and a second component. The first component is frequency-converted in the horizontal direction so that it has the same frequency band as the horizontal high-frequency component, and -vo/2 in the vertical direction and +f in the time direction. A signal frequency-shifted by l2 is used as a first modulation signal, and the second component is frequency-converted in the horizontal direction so that it has the same frequency band as the horizontal high-frequency component, and is frequency-converted in the vertical direction. l2 and a signal frequency-shifted by +f, /2 in the time direction as a second modulation signal, and a frequency that is the sum of the horizontal low-frequency component, the band-limited horizontal high-frequency component, the first modulation signal, and the second modulation signal. It transmits multiplexed signals.

Further, in the moving image signal transmission system of the third invention, V in the vertical direction. In a video signal transmission method in which a video signal having a frequency band f0 in the time direction is interlaced scanned and transmitted, the video signal has a high frequency band in the vertical direction of the image and a low frequency band in the temporal direction. Two components, a certain vertical high frequency component and a vertical low frequency component that is a vertical low frequency component of the image, are extracted, and the vertical low frequency component is divided into a horizontal low frequency component and a horizontal intermediate component according to the horizontal frequency of the image. The horizontal high frequency component is divided into three components: vertical high frequency component and horizontal high frequency component. The band is limited by a low-pass filter in the time-frequency space to obtain a band-limited horizontal high-frequency component, and the horizontal intermediate component is filtered in the vertical time-frequency space (ν, f) to produce a band-limited horizontal high-frequency component (ν, f). =(
4, ±vO/2, ±fO/2) is removed to obtain a band-limited horizontal intermediate component. Convert the frequency to have -, and vertically. l2 and a signal frequency-shifted by +f0l2 in the time direction as a modulated vertical high-frequency signal, and converting the frequency of the band-limited horizontal high-frequency component so that it has the same frequency band as the horizontal intermediate component in the horizontal direction, and in the vertical direction. A signal frequency-shifted by -vo/2 and +f0l2 in the time direction is used as a modulated horizontal high-frequency signal, and the horizontal low-frequency component, the band-limited horizontal intermediate component, the modulated horizontal high-frequency signal, and the modulated vertical high-frequency signal are added. It transmits frequency multiplexed signals.

Further, a moving image signal transmission method according to a fourth aspect of the present invention is a moving image signal transmission method in which a moving image signal having a frequency band of ν0 in the vertical direction and f0 in the time direction is transmitted by interlaced scanning. Two components are extracted: a vertical high frequency component that is a high frequency component in the vertical direction of the image and a low frequency component in the temporal direction, and a vertical low frequency component that is a low frequency component in the vertical direction of the image. The horizontal frequency component is divided into three components, a horizontal low frequency component, a horizontal intermediate component, and a horizontal high frequency component, according to the horizontal frequency of the image, and the horizontal high frequency component is divided into three components according to the horizontal frequency of the image. The band is limited by a filter to obtain a band-limited horizontal high-frequency component, and the horizontal intermediate component is filtered in the vertical time-frequency space (ν, f) to obtain (ν, 0 = (±
, 0/2, ±fo/2) to form a band-limited horizontal intermediate component, and the vertical high frequency component has the same frequency band as the horizontal intermediate component in the horizontal direction. Convert the frequency to +7 in the vertical direction. l2 and a signal frequency-shifted by +f0l2 in the time direction as a modulated vertical high-frequency signal, and converting the frequency of the band-limited horizontal high-frequency component so that it has the same frequency band as the horizontal intermediate component in the horizontal direction, and in the vertical direction. Ten ya. l2 and a signal frequency-shifted by +f0/2 in the time direction as a modulated horizontal high-frequency signal, and the horizontal low-frequency component, the band-limited horizontal intermediate component, the modulated horizontal high-frequency signal, and the modulated vertical high-frequency signal are added. It transmits frequency multiplexed signals.

Further, as a moving image signal transmission method according to a fifth invention, the moving image signal in the moving image signal transmission method described in the first to fourth inventions is a horizontal mid-range frequency component from the input moving image signal. Using the signal excluding the second intermediate component,
The horizontal second intermediate component may be subjected to band compression and time division multiplexed with the frequency multiplexed signal for transmission.

(Function) The present invention relates to a method for band compression and signal multiplexing when a moving image signal is band-compressed and transmitted.

As shown in the above-mentioned document 2, for the luminance signal, if the frequency component in the horizontal direction exceeds a certain level, it is filtered in the vertical/temporal frequency space (v, f) so that (v, f) = (±Vo/2, ±f0/2) of 4
It is said that even if signal components centered around points are removed, there is no significant effect on the image quality of general images. This is because in the horizontal high frequency component, there are signal components up to the temporal high frequency region in the motion domain, but the vertical component is 7. This is because there are few signal components of l2 or higher, and there are almost no frequency components in the time direction in the stationary region. Therefore, according to the first to fourth aspects of the invention, the signal components in this frequency domain are removed, and the high frequency components in the horizontal or vertical direction are modulated and multiplexed on the empty space, thereby eliminating the deterioration caused by removing the signal components. This means that it is possible to provide higher-definition images than conventional methods without causing too much trouble.

Furthermore, it is said that human visual characteristics make it difficult to detect resolution degradation in an oblique direction than in the horizontal or vertical direction of an image. Furthermore, it is known that, as a visual characteristic of humans, high-definition components of images cannot be detected much in moving areas. Therefore, in the fifth invention, in the first to fourth inventions, a frequency component that is high in the horizontal direction and also in the vertical direction, or a frequency component that is high in the horizontal direction and high in the temporal direction. By removing certain frequency components, it becomes possible to further compress the band without causing significant deterioration in image quality.

(Example) Next, an example of the present invention will be described using FIGS. 1 to 11. Below, as an example, the number of scanning lines will be explained. ×2 pieces,
Using a progressive scan black and white television video signal as input,
A case will be described in which the data is transmitted to the receiving side using interlaced scanning after performing band limiting processing and multiple processing. Further, here, the horizontal signal band p of the input moving image signal is p<p. , the signal band in the vertical direction, is <, the signal band f in the time direction is f<f. Suppose that

01 In addition, the vertical frequency band of the transmission signal in the case of transmission using interlaced scanning is, for example, v, = vox 3/
Suppose that it is 4. Furthermore, processing in the time direction is performed without distinguishing between moving regions and static regions.

First, an embodiment of the first invention will be described. FIG. 6 is a block diagram showing the basic configuration of an embodiment of the first invention, and FIG. 1 is a diagram showing a signal band that can be transmitted by the embodiment of FIG. A sequentially scanned moving image signal 50 is input, and first, the moving image signal 50 is divided into horizontal low frequency components 110 (0≦P<1-12) in the horizontal band division circuit 20.
It is divided into a horizontal intermediate component 111 (p2≦Pill1) and a horizontal high frequency component 112 (p,≦11<11o). At this time, as an example, }11-p2=(po-111)/2. The horizontal high frequency component 112 is F. In the router circuit 5, low-pass filter processing is performed in the vertical/temporal frequency space, and as an example, as shown in FIG. 1, v<vo/4 in the vertical direction and f<r in the time direction. The band is limited to /4, and the band is further limited to 172 by removing diagonal components in the vertical/temporal frequency space. The output signal 116 of the filter circuit 5 is equally divided into two by the horizontal frequency component in the horizontal band division circuit 21, and the first component 117 (p0≦p<p1/2 + }l
o/2) and the second component 118 (p,/2+po/2≦p
<p. ). In the modulation circuit 22, the first component 117 is -(p1-112) in the horizontal direction and +vO/in the vertical direction.
2 and the frequency is shifted by +f0/2 in the time direction to become the first modulated signal 119. The second component 118 is transmitted in the modulation circuit 23 in the horizontal direction -'t92)X2 and in the vertical direction. l2 and the frequency is shifted by +f0l2 in the time direction to become the second modulated signal 120. It is assumed that the first component 117 and the second component 118, which are sequentially scanned before frequency shifting in the modulation circuits 22 and 23, are converted to interlaced scanning. However, no new bandwidth restriction processing is performed here. In addition, the horizontal intermediate component 111 is input to the filter circuit 4 in the vertical/temporal frequency space (ν, f).
By filtering ('s', f) = (±ν./2
, ±f, /2).
Then, the signal component is removed by the signal band of the second modulated signal 120, resulting in a band-limited horizontal intermediate component 113. After the horizontal low frequency component 110 and the band-limited horizontal intermediate component 113 are added, the scan conversion circuit 6 generates a sequentially scanned addition signal 1.
14 to an interlaced scanning addition signal 115.

At this time, before scan conversion, it is necessary to perform filter processing for band limitation in the vertical and temporal frequency spaces. After the above band limiting and modulation processing, the interlaced scanning addition signal 115, the first modulation signal 119, and the second modulation signal 120 are added and transmitted as a frequency multiplexed signal 121 to the receiving side. At this time, the frequency multiplexed signal 121 has a frequency band as shown in FIG.

That is, <v, f)= (vo/2, fo/2),
The first modulated signal 11 centered on (-vo/2+-fo/2)
9 is frequency multiplexed and (ν, f) = (1 v./2, fo/
2), (v./2, -fo/2), and the second modulated signal 120 is multiplexed around it.

Note that in the modulation circuits 22 and 23, the first component 117
is frequency-shifted by +ν0/2 in the vertical direction and +f0/2 in the time direction, and the second component 118 is shifted vertically by -vo/2.
2 and the frequency is shifted by +f0/2 in the time direction, which shifts the first component 117 by −ν0/2 in the vertical direction.
And the frequency is shifted by +fo/2 in the time direction, and the second component 118 is +V in the vertical direction. /2 and +f in time direction
The frequency may be shifted by o2.

Further, in the embodiment of FIG. 6, the first component 117 and the second component 1
18 is divided into two by looking at the frequency components in the horizontal direction, but it is also possible to divide into two by looking at other frequency components. However, it is necessary that a band restriction process corresponding to this process be performed.

In this embodiment, the horizontal signal band p is
. It becomes possible to transmit a signal band of (>μ1).

Next, an embodiment of the second invention will be described. FIG. 7 is a Bronok diagram showing the basic configuration of an embodiment of the second invention, and FIG. 2 is a diagram showing a signal band that can be transmitted by the embodiment of FIG. A sequentially scanned moving image signal 50 is manually input, and first, the vertical high frequency extraction circuit 24 extracts a vertical high frequency component 122 that is high frequency in the vertical direction of the image and low frequency in the temporal direction.

For example, as shown in FIG. 2, the vertical high frequency component 122 has 0≦p<114<Po in the horizontal direction and v1 (in the vertical direction).
=ν. x3/4)≦ν×ν. , O≦f<r in the time direction.

It is assumed that after the band is limited to 14, the band is further limited to 1/2 in the vertical/temporal frequency space. The vertical high-frequency component 122 is divided into two equal parts by the horizontal frequency component in the horizontal band dividing circuit 25, and is divided into a first component 124 (0≦p<p4/2) and a second component 125 (p4/2).
2≦P<l-14).

The first component 124 is horizontally }1 in the modulation circuit 26.
3 ( ”Po-¥l,s/2), vertically -7./
The first modulated signal 126 is frequency-shifted by 2 and +f0/2 in the time direction. The second component 125 is frequency-shifted by po − 114 in the horizontal direction, +v0/2 in the vertical direction, and +f0/2 in the time direction in the modulation circuit 27 to become a second modulation signal 127.

It is assumed that after frequency shifting in the modulation circuits 26 and 27, the sequential scanning signal is converted to interlaced scanning. However, no new bandwidth restriction processing is performed here. Further, the vertical high frequency component 122 of the moving image signal 5o is
The vertical low frequency component 123 from which p3 is subtracted is input to the horizontal band dividing circuit 28, and is divided into a horizontal low frequency component 128 (0≦11<1''3) and a horizontal high frequency component 129 (p3≦P) depending on the horizontal frequency of the image. <p.).The horizontal high frequency component 129 is divided into two components of
Exactly the same vertical/temporal frequency space as filter circuit 4 in the figure (
By filtering at ν, f), (ν, f)=(±vo/2
, ±fo/2).
Then, the signal component is removed by the signal band component of the second modulated signal 127, resulting in a band-limited horizontal high-frequency component 130. After the horizontal low-frequency component 128 and the band-limited horizontal high-frequency component 130 are added, the scan conversion circuit 6 converts the progressive scan addition signal 131 to the interlaced scan addition signal 132 using the same process as the scan conversion circuit 6 in FIG. is converted to After the above band limiting and modulation processing, the interlaced scanning addition signal 132
, the first modulated signal 126 and the second modulated signal 127 are added and transmitted as a frequency multiplexed signal 133 to the receiving side.

Note that in the modulation circuits 22 and 23, the first component 124
-7 vertically. /2 and the frequency is shifted by 10f, /2 in the time direction, and the second component 125 is shifted vertically by +ν0/
2 and the frequency is shifted by +fo/2 in the time direction, which shifts the first component 124 by +ν0/2 in the vertical direction.
and the frequency is shifted by +fl2 in the time direction, and the second component 125 is -v0/2 in the vertical direction and +fo in the time direction.
The frequency may be shifted by /2.

In the embodiment shown in FIG. 7, the first component 124 and the second component 1
25 is divided into two by looking at the frequency components in the horizontal direction, but it is also possible to divide into two by looking at other frequency components. However, it is necessary that a band restriction process corresponding to this process be performed.

Further, the second invention can also be realized by the structure shown in FIG. That is, when determining the vertical high-frequency component 122 in the embodiment shown in FIG. 7, the progressive scanning input moving image signal 50 is once scan-converted to become interlaced scanning, and then reverse scan-converted to decode the progressive scanning signal. This method considers the difference between this decoded signal and the input moving image signal 50 as a vertical high frequency component. First, the input moving image signal 50 is converted into an interlaced scanning signal 134 in the scan conversion circuit 6 through the same processing as in the scan conversion circuit 6 of FIG. Interpolation is performed on this interlaced scanning signal 134 in the scan conversion circuit 9 using the band-limiting filter used in the scan conversion circuit 6 to obtain a decoded sequential scanning signal 135 of progressive scanning. This decoded sequential scanning signal 1
35 from the moving image signal 50, this difference signal 1
36 is subjected to exactly the same band-limiting processing as that performed by the vertical high-frequency extracting circuit 24 in FIG. 7 in the filter circuit 10 to obtain a vertical high-frequency component 137. Vertical high frequency component 13
7 is subjected to exactly the same processing as the vertical high frequency component 122 in FIG. 7, and finally the first modulated signal 1
39 and a second modulated signal 141 are obtained. Further, the interlaced scanning signal 134 is generated by a horizontal band dividing circuit 29 and a filter circuit 30, in exactly the same way as the horizontal band dividing circuit 28 and filter circuit 4 in FIG. Get 144.

Here, the only difference between the horizontal band division circuit 28 and the filter circuit 4 shown in FIG. 7 is that the input and output signals in FIG. 7 are sequentially scanned, while those in FIG. 8 are interlaced. . Horizontal low frequency segment 1 obtained as above
42 and band-limited horizontal high frequency component 144? l modulation signal 13
9 and the second modulated signal 141 are added to form the frequency multiplexed signal 1.
45 to the receiving side.

According to this embodiment, the vertical signal band V can be maintained even when transmitting by interlaced scanning. It becomes possible to transmit a signal band of (>9■).

Next, an embodiment of the third invention will be described. FIG. 9 is a block diagram showing the basic configuration of an embodiment of the third invention, and FIG. 3 is a diagram showing a signal band that can be transmitted by the embodiment of FIG. A sequentially scanned moving image signal 50 is input, and first, the vertical high frequency extraction circuit 1 extracts a vertical high frequency component 51 that is high frequency in the vertical direction of the image and low frequency in the temporal direction. As an example, the vertical high-frequency component 51 has the following relationship in the horizontal direction as shown in FIG.
/”s), in the vertical direction 7■ (=,.
It is assumed that the band is further limited to 1/2 in the vertical/temporal frequency space. The vertical high frequency component 51 is horizontally converted to 116 (= p5 - 117) in the modulation circuit 2.
, -v0/2 in the vertical direction and +f in the temporal direction. The frequency is shifted by /2 and becomes a modulated vertical high frequency signal 53. It is assumed that after frequency shifting in the modulation circuit 2, the sequential scanning signal is converted to interlaced scanning. However, no new bandwidth restriction processing is performed here. Also,
The vertical low frequency component 52, which is a signal obtained by subtracting the vertical high frequency component 51 from the moving image signal 50, is input to the horizontal band division circuit 3, and is divided into horizontal low frequency components 54 (0≦1'') depending on the horizontal frequency of the image. < 1”6) and the horizontal intermediate component 55 (P
6≦11<p5) and horizontal high frequency component 56 (p5≦p<
p. ) is divided into three components. In the filter circuit 5, the horizontal high frequency component 56 is transmitted to the vertical component, which is exactly the same as the filter circuit 5 in FIG. 6, as an example. Low-pass filtering in time-frequency space is performed. The output signal 59 of the filter circuit 5 is outputted in the modulation circuit 7 in the horizontal direction by -(p5-116
), vertically -V. /2 and ten f, /2 in the time direction
The modulated horizontal high frequency signal 61 is frequency-shifted by .

It is assumed that after frequency shifting in the modulation circuit 7, the sequential scanning signal is converted to interlaced scanning.

However, no new bandwidth restriction processing is performed here. The horizontal intermediate component 55 is created in the filter circuit 4 in exactly the same vertical/temporal frequency space (v, f) as the filter circuit 4 in FIG.
By filtering (ν, f) = (±v./2, ±f
0/2), signal components corresponding to the signal bands of the modulated vertical high-frequency signal 53 and the modulated horizontal high-frequency signal 61 are removed to form a band-limited horizontal intermediate component 57. After the horizontal low-frequency component 54 and the band-limited horizontal intermediate component 57 are added, the scan conversion circuit 6 converts the progressive scanning addition signal 58 into the interlaced scanning addition signal 60 using the same process as the scan conversion circuit 6 shown in FIG. converted. After the above band limiting and modulation processing, the interlaced scanning addition signal 60, the modulated vertical high frequency signal 53, and the modulated horizontal high frequency signal 61 are added and transmitted as a frequency multiplexed signal 62 to the receiving side.

Further, when extracting the vertical high frequency component in the embodiment of FIG. 9, it may be realized using a configuration similar to that shown in FIG. 8 as the embodiment of the second invention.

In the embodiment shown in FIG. 9, the vertical high frequency component 51 is first obtained from the moving image signal 50, and then the vertical low frequency component 52 is divided into 3 by the horizontal frequency component in the horizontal band dividing circuit 3.
The moving image signal 50 is first divided into three horizontal frequency components by the horizontal band division circuit 3.
Alternatively, the vertical high frequency component may be extracted from the component including the low frequency component among the divided frequency components.

According to this embodiment, even when transmitting by interlaced scanning using a transmission path of signal band p5, horizontal signal band 'o(〉l''5
), vertical signal band,. It becomes possible to transmit the signal band of (〉〉,).

Next, an embodiment of the fourth invention will be described. The embodiment of the fourth invention may be the embodiment of the third invention by changing the method of modulating the vertical high frequency component and the horizontal high frequency component. That is, for example, in the third embodiment of the invention described using FIG.
l in the vertical direction -v0/2 and +r in the time direction. /2
Shift the horizontal high frequency component 59 by -1 in the vertical direction.
. /2 and the frequency is shifted by +f0/2 in the time direction. /2 and +r in the time direction. The frequency is shifted by l2, and the horizontal high frequency component 59 is changed in frequency by +v0/2 in the vertical direction and by +fo/2 in the time direction.

By doing this, compared to the third invention, the multiplexing positions of the vertical high frequency component and the horizontal high frequency component are reversed, and the signal band that can be transmitted becomes the same as the third invention.

Next, an embodiment of the fifth invention will be described. Here, as an example, in the third embodiment of the invention shown in FIG. 9, a signal obtained by removing a horizontal second intermediate component, which is a horizontal mid-range frequency component, from the input moving image signal is used as the moving image signal 50, A case will be described in which the horizontal second intermediate component is subjected to band compression and then time-division multiplexed with other signal components and transmitted. In this embodiment, a case will be described in which the vertical high-frequency component is extracted before the horizontal second intermediate component, but the order may be either.

FIG. 10 is a Bronnoch diagram showing the basic configuration of an embodiment of the fifth invention, and FIG. 4 is a diagram showing a signal band that can be transmitted by the embodiment of FIG. 10. A sequentially scanned moving image signal 50 is input, and first, the vertical high frequency extraction circuit 8 extracts a vertical high frequency component 63 that is high frequency in the vertical direction of the image and low frequency in the temporal direction. The vertical high frequency component 63 is
An example is shown in Figure 4. In the horizontal direction, O≦11<
1111 (=}lo-118), in the vertical direction V■ (
= voX 3/4)≦v<v. , 0≦ in the time direction
r<f. It is assumed that after the band is limited to /4, the band is further limited to 1/2 in the vertical/temporal frequency space. The vertical high frequency component 63 is ll1o (=1-19-P1■) in the horizontal direction and -v in the vertical direction in the modulation circuit 11.
o/2 and frequency shift by +f0/2 in the time direction. A modulated vertical high frequency signal 64 is obtained. In addition, modulation circuit 1
1, the sequential scanning signal is converted into interlaced scanning after frequency shifting. However, no new bandwidth restriction processing is performed here. In addition, the moving image signal 5
The vertical low frequency component 65, which is a signal obtained by subtracting the vertical high frequency component 63 from 0, is input to the horizontal band division circuit 12,
Depending on the horizontal frequency of the image, the horizontal low frequency component is 90 (O≦
p<p1o) and horizontal intermediate component 91 (p,o≦p<μ9)
, a horizontal second intermediate component 93 (p,≦p<}l8), and a horizontal high-frequency component 92 (¥18≦p<p.). The horizontal high-frequency component 92 is subjected to low-pass filter processing in the filter circuit 5 in exactly the same vertical/temporal frequency space as the filter circuit 5 in FIG. 6, for example.

The output signal 96 of the filter circuit 5 is -(P8-11,.) in the horizontal direction and -V in the vertical direction in the modulation circuit 13. l
2 and the frequency is shifted by 10 fJ2 in the time direction to become a modulated horizontal high frequency signal 99. It is assumed that after frequency shifting in the modulation circuit 13, the sequential scanning signal is converted to interlaced scanning. However, no new bandwidth restriction processing is performed here. The horizontal intermediate component 91 is filtered in the filter circuit 4 in exactly the same vertical time frequency space (ν, f) as the filter circuit 4 in FIG.
, D=(±ν./2, ±fo/2), the signal components are removed by the signal bands of the modulated vertical high-frequency signal 64 and the modulated horizontal high-frequency signal 99 to form a band-limited horizontal intermediate component. It becomes 94. After the horizontal low-frequency component 90 and the band-limited horizontal intermediate component 94 are added, the scan conversion circuit 6 converts the sequential scan addition signal 95 into the interlaced scan addition signal 98 by the same process as the scan conversion circuit 6 of FIG. converted. After the above band limiting and modulation processing, the interlaced scanning addition signal 98, the modulated vertical high frequency signal 64, and the modulated horizontal high frequency signal 9
9 is added to form a frequency multiplexed signal 100. Further, the horizontal second intermediate component 93 is applied to the band compression circuit 14 in the vertical direction such that O≦v<v, as shown in FIG. 4, for example. l
2. O≦f<f in the time direction. After being band-limited to l2 and further band-limited to 1/2 in the vertical/time-frequency space, the frequency is shifted by -p9 in the horizontal direction, and then thinned out by 1/2 in the vertical direction and 1/2 in the temporal direction. is applied and converted to interlaced scanning, resulting in a compressed band signal 97. Finally, in the selection circuit 15, the time axis is compressed or expanded so that the frequency multiplexed signal 100 and the band compressed signal 97 have the same signal band, and then time division multiplexed and transmitted to the receiving side as a transmission signal 101. .

This embodiment has a narrower signal band than the third invention (
or in a short time) horizontal signal band po, vertical signal band V. (>v1) signal band transmission becomes possible.

In the embodiment shown in FIG. 10, based on the embodiment shown in FIG. 9, the horizontal second intermediate component of the moving image signal 50 is subjected to band compression and then time-division multiplexed with other signal components. Although the case of transmission has been described, the embodiment shown in FIG. 6, FIG. 7, or FIG. 8 may be used instead of the embodiment shown in FIG.

The above are the first to fifth embodiments of the invention. Note that in the above embodiments, the moving region and the static region are not distinguished when processing in the time direction, but adaptive processing such as multiplexing high-definition signals only in the static region may be performed. good. Furthermore, it goes without saying that color moving image signals can be transmitted by separately transmitting color signals in a time-division manner. Also,
In the case of multiplexing and transmitting horizontal detail information as in the first invention, an interlaced scanning signal may be used as the input moving image signal. Further, the number of scanning lines of the input and output moving image signals does not need to be equal; for example, a signal obtained by converting the number of scanning lines from a higher definition signal may be used as the moving image signal 50 of the above embodiment.

(Effects of the Invention) As described above, according to the present invention, when transmitting black-and-white moving image signals, it is possible to transmit higher-definition signals in the same transmission band compared to the conventional technology. Become.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a band limiting method in an embodiment of the first invention, FIG. 2 is a diagram showing a band limiting method in an embodiment of the second invention, and FIG. 3 is a diagram showing a band limiting method in an embodiment of the second invention. FIG. 4 is a diagram showing a band limiting method in an embodiment of the fifth invention; FIG. 5 is a diagram showing a signal multiplexing method in an embodiment of the first invention; Figure 6 is a diagram showing the configuration of an embodiment of the first invention, Figures 7 and 8.
9 is a diagram showing the structure of an embodiment of the second invention, FIG. 9 is a diagram showing the structure of an embodiment of the third invention, and FIG.
FIG. 11 is an explanatory diagram of a conventional system. In the figure, 1, 8. 24... Vertical high frequency extraction circuit, 2, 7,
11, 13, 22, 23, 26. 27...
・Modulation circuit, 3, 12, 20, 21, 25,
28. 29...Horizontal band division circuit, 4, 5,
10, 30...filter circuit, 6...scan conversion circuit, 9...inverse scan conversion circuit, 14...band compression circuit, 15...selection circuit. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5

Claims (5)

[Claims] (1) In a video signal transmission method in which a video signal having a frequency band of ν_0 in the vertical direction and f_0 in the time direction is transmitted by interlaced scanning, the video signal is divided into horizontal low frequency components by the frequency in the horizontal direction of the image. is divided into three components, a horizontal intermediate component and a horizontal high frequency component, and the horizontal high frequency component is band-limited by a low-pass filter in the vertical/temporal frequency space to form a band-limited horizontal high frequency component; The band-limited horizontal high-frequency component is frequency-divided into two components, a first component and a second component, and the first component is frequency-divided so that it has the same frequency band as the horizontal intermediate component in the horizontal direction. The converted signal whose frequency is shifted by +ν_0/2 in the vertical direction and +f_0/2 in the time direction is used as the first modulation signal, and the second component is frequency-shifted in the horizontal direction so that it has the same frequency band as the horizontal intermediate component. The converted signal whose frequency is shifted by −ν_0/2 in the vertical direction and +f_0/2 in the time direction is used as a second modulation signal, and the signal is vertically shifted with respect to the horizontal intermediate component.
By filtering in time-frequency space (ν, f), (ν, f
)=(±ν_0/2, ±f_0/2), the signal components centered at the four points are removed to obtain a band-limited horizontal intermediate component, and the horizontal low-frequency component, the band-limited horizontal intermediate component, and the first modulation are A moving image signal transmission system characterized in that a frequency multiplexed signal obtained by adding the signal and the second modulation signal is transmitted. (2) In a video signal transmission method in which a video signal having a frequency band of ν_0 in the vertical direction and f_0 in the time direction is transmitted by interlaced scanning, the video signal has a high frequency band in the vertical direction of the image and In the time direction, two components are extracted: a vertical high frequency component that is a low frequency component and a vertical low frequency component that is a low frequency component in the vertical direction of the image, and the vertical low frequency component is horizontally divided by the frequency in the horizontal direction of the image. It is divided into two components, a low-frequency component and a horizontal high-frequency component, and the horizontal high-frequency component is filtered in the vertical time-frequency space (ν, f) to calculate (ν, f)=
The signal components centered around the four points (±ν_0/2, ±f_0/2) are removed to create a band-limited horizontal high-frequency component, and the vertical high-frequency component is frequency-divided to separate the first and second components. The first component is frequency-converted in the horizontal direction so that it has the same frequency band as the horizontal high-frequency component, and the frequency is changed by −ν_0/2 in the vertical direction and +f_0/2 in the time direction. The shifted signal is used as the first modulation signal, and the second
The frequency of the component is converted horizontally so that it has the same frequency band as the horizontal high frequency component, and +ν_0/2 in the vertical direction.
and a frequency-multiplexed signal obtained by adding the horizontal low-frequency component, the band-limited horizontal high-frequency component, the first modulation signal, and the second modulation signal, with a signal frequency-shifted by +f_0/2 in the time direction as a second modulation signal. A video signal transmission method characterized by transmitting. (3) In a moving image signal transmission method in which a moving image signal having a frequency band of ν_0 in the vertical direction and f_0 in the time direction is transmitted by interlaced scanning, the moving image signal has a high frequency band in the vertical direction of the image and In the time direction, two components are extracted: a vertical high frequency component that is a low frequency component and a vertical low frequency component that is a low frequency component in the vertical direction of the image, and the vertical low frequency component is horizontally divided by the frequency in the horizontal direction of the image. It is divided into three components: a low frequency component, a horizontal intermediate component, and a horizontal high frequency component, and the horizontal high frequency component is band-limited by a low-pass filter in the vertical and temporal frequency space to generate a band-limited horizontal high frequency component. component, and filter the horizontal intermediate component in the vertical time-frequency space (ν, f) to generate a signal component centered at the four points of (ν, f) = (±ν_0/2, ±f_0/2). is removed to obtain a band-limited horizontal intermediate component, and the vertical high frequency component is frequency-converted so that it has the same frequency band as the horizontal intermediate component in the horizontal direction, and −ν_0/2 in the vertical direction and +f_0/ in the time direction. 2
The signal frequency-shifted by 0.05 is used as a modulated vertical high-frequency signal, and the band-limited horizontal high-frequency component is frequency-converted in the horizontal direction so that it has the same frequency band as the horizontal intermediate component, and in the vertical direction by −ν_0/2 and time. A frequency-multiplexed signal in which a signal frequency-shifted by +f_0/2 in the direction is a modulated horizontal high-frequency signal, and the horizontal low-frequency component, the band-limited horizontal intermediate component, the modulated horizontal high-frequency signal, and the modulated vertical high-frequency signal are added. A video signal transmission method characterized by transmitting. (4) In a video signal transmission method in which a video signal having a frequency band of ν_0 in the vertical direction and f_0 in the time direction is transmitted by interlaced scanning, the video signal has a high frequency band in the vertical direction of the image and In the time direction, two components are extracted: a vertical high frequency component that is a low frequency component and a vertical low frequency component that is a low frequency component in the vertical direction of the image, and the vertical low frequency component is horizontally divided by the frequency in the horizontal direction of the image. It is divided into three components: a low frequency component, a horizontal intermediate component, and a horizontal high frequency component, and the horizontal high frequency component is band-limited by a low-pass filter in the vertical and temporal frequency space to generate a band-limited horizontal high frequency component. component, and filter the horizontal intermediate component in the vertical time-frequency space (ν, f) to generate a signal component centered at the four points of (ν, f) = (±ν_0/2, ±f_0/2). is removed to obtain a band-limited horizontal intermediate component, and the vertical high frequency component is frequency-converted horizontally so that it has the same frequency band as the horizontal intermediate component, and +v_0/2 in the vertical direction and +f_0/2 in the time direction.
The signal whose frequency has been shifted by 0.05 is used as a modulated vertical high-frequency signal, and the band-limited horizontal high-frequency component is frequency-converted in the horizontal direction so that it has the same frequency band as the horizontal intermediate component, and +ν_0/2 in the vertical direction and +ν_0/2 in the time direction. A signal frequency-shifted by +f_0/2 is used as a modulated horizontal high-frequency signal, and a frequency multiplexed signal is obtained by adding the horizontal low-frequency component, the band-limited horizontal intermediate component, the modulated horizontal high-frequency signal, and the modulated vertical high-frequency signal. A video signal transmission method characterized by the transmission of video signals. (5) In the moving image signal transmission method according to claim 1, 2, 3, or 4, the moving image signal is a horizontal second medium frequency component from the input moving image signal in the horizontal direction.
A moving image signal transmission system characterized in that a signal excluding an intermediate component is used, the second horizontal intermediate component is subjected to band compression, and is time-division multiplexed with the frequency multiplexed signal for transmission.