JPS6086994A - Multiple sub-sample transmission system of high- definition television - Google Patents

Abstract

PURPOSE:To execute a narrow band transmission of a high definition TV picture signal by converting a time division multiple picture signal to a transmitting picture signal of a narrow band, transmitting it together with a movement information signal of a picture, performing an interpolation to the transmitting picture signal and reloading it, in accordance with a received movement information signal. CONSTITUTION:A luminance signal Y and a color signal C for constituting a high definition TV picture signal are led to a TCI encoder 1, brought to time base compression and multiprocessing supplied to a sampling circuit 2, and also supplied to the circuit 2 through an LPF3. Also, said signals are supplied to a movement information detecting circuit 4, and movement information of a picture is supplied to the circuit 2. The circuit 2 performs sampling of a four field period to said information, and sends it out to a transmission line through a multiple circuit 5. A receiving signal is divided into a picture transmitting signal and a movement information signal by a separating circuit 6, and led to a sub-sample decoder 7. The decoder 7 performs an interpolation to the transmitting picture signal in accordance with the movement information signal and sends it out to a TCI decoder 8. The decoder 8 separates the luminance signal and the color signal, and thereafter, reloads them to signals Y, C by expanding the time base. In this way, the signal can be transmitted in a narrow area.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to an image signal transmission method that transmits a wideband high-definition television image signal by narrowing the band, and in particular, relates to a narrowband transmission method suitable for narrowband transmission of image signals. This system combines multiple systems to enable sufficiently narrowband transmission of high-definition television image signals.

(Prior art) Recently, with the advancement of communication technology using geostationary satellites, satellite broadcasting technology has reached the stage of practical use.1 However, in order to effectively utilize satellite broadcasting technology, broadband high-definition television image signals are required. It is desired to achieve a particularly high level of image information transmission by broadcasting images. However, while communication technology using geostationary satellites requires the transmission of information signals to be made as narrow as possible in order to improve the efficiency of information signal transmission, high-definition television image signals require high quality.・In order to improve the performance, it is necessary to make the transmission information signal as wide as possible. Therefore, in order to put satellite broadcasting of high-definition television image signals to practical use, it is necessary to transmit high-definition television image signals in extremely narrow bands. However, all of the image signal narrowband transmission methods that have been proposed so far are based on the time axis compression multiplexing (TOI) transmission described later, which is said to have reached the practical level especially in terrestrial image information transmission. The drawback is that if each method or even sub-sampling transmission method is applied individually, it cannot be fully put to practical use in satellite broadcasting of high-definition television image signals.

(Summary of the Invention) An object of the present invention is to eliminate the above-mentioned conventional drawbacks, and to mutually implement image signal narrowband transmission systems that cannot achieve satellite broadcasting of high-definition television image signals by themselves. Image signal narrowbanding that allows high-definition television image signals to be easily combined without interference and transmitted in a narrow enough band to realize advanced satellite broadcasting using a circuit device with a simple configuration. It is an object of the present invention to provide a transmission system, particularly a high-definition television multiple subsampled transmission system.

That is, the high-definition television multiplex sub-sampling transmission system of the present invention uses time-axis compression multiplexing (TGI) transmission in which the luminance signal and chrominance signal of a color image signal are time-axis compressed and time-division multiplexed for each horizontal scanning period. By combining this method with a subsampling transmission method in which the sampled image signal is subsampled and transmitted, such as by converting the sampled image signal into dot interlace scanning at a four-field period, a wideband high-quality television image signal can be highly narrowed. The luminance signal and chrominance signal of the sampled high-definition television image signal are compressed on the time axis to form a time-division multiplexed image signal, and the time-division multiplexed image signal is transmitted in a predetermined manner. subsampling each of a plurality of fields and converting it into a narrowband transmission image signal, and transmitting a motion information signal corresponding to the amount of movement of the image represented by the high-definition television image signal together with the transmission image signal, Restoring the time-division multiplexed image signal by applying interpolation to the subsampled and converted narrowband transmission image signal according to the motion information signal received together with the transmission image signal, and restoring the time division multiplexed image signal. The present invention is characterized in that after separating the luminance signal and color signal of the time-division multiplexed image signal, the time axis of each signal is expanded to restore the high-definition television image signal.

(Example) The present invention will be described in detail below with reference to the drawings.

First, two types of image signal narrowband transmission systems that are combined and applied to high-definition television image signals in the transmission system of the present invention will be outlined.

That is, the time axis compression multiplexing (TOI) transmission method is as described in, for example, the specification of Japanese Patent Application No. 108374/1983 filed by the applicant or the patent specification filed on August 80, 1988. The luminance signal Y and color signal O of the television image signal formed by guiding the primary color image signal ゛ output from a color television camera to a color enhancer are subjected to time axis compression at appropriate ratios, respectively. As shown in FIG. 2, the color signal C and the luminance signal Y, which are time-base compressed, are multiplexed in a time-division manner during the synchronization signal 5YNO for each horizontal scanning period IH. If the transmission periods of the luminance signal Y and the chrominance signal C are shifted and transmitted by such time division multiplexing, the bandwidth of each signal itself will be wavered somewhat due to time axis compression, but when narrowband transmission is performed, the normal carrier chrominance signal Mutual interference between the luminance signal Y and the color signal C, which significantly deteriorates the image quality that occurs when the luminance signal is frequency multiplexed onto the luminance signal, does not occur at all, and narrowband transmission can be performed with good image quality.

On the other hand, in the sub-sampling transmission method, for example, as described in Japanese Patent Application No. 58-93358 filed by the applicant, an image signal representing one image is sampled for each pixel point. Instead of transmitting the values sequentially as they are, each field is thinned out and transmitted in a predetermined order over multiple fields, and on the receiving side, adjacent sample points transmitted in the previous and subsequent fields are transmitted for each field. The image for each field is restored by interpolating the thinned out sample values by referring to the sample values in the field.

That is, for example, as shown in Figure 2, where sequential sample values are divided into four symbols, sample values thinned out at a 4-point period are transmitted for each field, and one image is created at a 4-field period. Complete the transmission of information. Therefore, the amount of information transmitted for each field can be reduced by a large amount of $%.
However, the sample value at the same sample point changes for each field, except for still images, which can be reconstructed by directly superimposing the thinned-out sample values by shifting two sample points for each field. Various proposals have been made regarding interpolation of thinned sample values for moving images.

As is clear from the above, although the TCI transmission method and the sub-sampling transmission method are both narrowband transmission methods for image signals, they do not mutually interfere with each other in signal processing for the same image signal. In other words, in the TCC low transmission system, the sample values of the luminance signal and chrominance signal are divided into the front half and the second half for each scanning period, and the sample values of the luminance signal and the chrominance signal are arranged so that the interval between the sample points of each field is narrowed. , in the same way as normal transmission of only the luminance signal, it is possible to transmit the luminance signal and chrominance signal by simply shortening the interval between sample points. Regardless of the information content of the values, the order of sample value transmission is changed and thinned-out transmission is performed, and the arrangement of sample values is restored by interpolation on the receiving side.Therefore, on the receiving side,
If interpolation is considered in the same way as in the past, the TOI transmission method and the sub-sampling method can be combined and applied to the same image signal without mutual interference.

The present invention skillfully utilizes the above-mentioned mutually non-interfering relationship with the TCC low transmission method and the sub-sampled transmission method to significantly narrow down the extremely wideband high-definition television image signal using a circuit device with a relatively simple configuration. It is designed so that it can be transmitted over multiple bands. That is, in the high-definition television multiple subsampling transmission system of the present invention, after each of the luminance No. 46 and color signals are sampled and integrated using the TOI transmission system, a Together with the motion information signal, inter-field and inter-frame subsampling is applied, a synchronization signal is multiplexed, and the carrier wave is FM modulated and transmitted along with the audio signal. After receiving, it is decomposed into an image signal, a synchronization signal, and an audio signal. Then, after motion correction and sample amount interpolation are applied to the image (i), the TOI decoder separates it into a luminance signal and a color signal to restore the original high-definition television image signal.

The basic configurations of circuit devices on the transmitting side and receiving side in the high-definition television multiplexed subsampled transmission system of the present invention are shown in FIGS. 8(a) and 8(b), respectively.

In the basic configuration of the transmitting side circuit device shown in FIG. 8(a), the luminance signal Y and the color signal Ct-TOI encoder 1, which constitute a high-definition television image signal, are guided and subjected to time axis compression. Then, time division multiplexing is performed in the form shown in the first figure to form a TOI signal. The TOI signal is directly supplied to the sub-sampling circuit 2, and the low-frequency component extracted through the low-pass filter 8 is also supplied to the sub-sampling circuit 2. Further, the TOI signal is supplied to a motion information detection circuit 4 to detect a motion vector of an image represented by a TCC multiplied signal using an interframe difference signal or the like, and information on the image motion is also supplied to a sub-sampling circuit 2. In the sub-sampling circuit 2, as described in the above-mentioned Japanese Patent Application No. 5S-93aSs, the TOI signal is sub-sampled with a period of 4 fields as described above with reference to FIG. The TOI signal subjected to the above processing is supplied to the multiplexing circuit 5, and the motion vector from the motion information detection circuit 4 is multiplexed during the blanking period, etc., and then sent to the transmission path.

Next, in the basic configuration of the receiving side circuit device shown in FIG.
After separating them from each other, they are guided to the sub-sample decoder 7, and for still images, the original TOI signal is restored by superimposing the incoming sample values that have been sequentially thinned out and transmitted at a 4-field period, and , for moving images,
The sample values of each field are thinned out at a period of 4 fields, and the sample values of each field are interpolated based on the adjacent sample values of the adjacent fields while referring to the motion vectors that were also transmitted. and restore the TOI signal. Next, the restored TOI signal is supplied to the '[' CI decoder 8 to extract the luminance signal Y and the chrominance signal C, and time axis expansion is applied to each of them to restore the original luminance signal Y and chrominance signal C. to reproduce high-definition television image signals.

Next, examples of specific detailed configurations of circuit devices on the transmitting side and receiving side according to the transmission system of the present invention based on the above-mentioned basic configuration are shown in FIGS. 4(a) and 4(b), respectively. As is clear from the figure, these specific detailed configurations are shown in the eighth section.
The configuration is such that necessary circuit devices are added before and after the basic configuration shown in FIGS. (a) and (b), respectively. That is, in the transmitting side circuit device shown in FIG.
A luminance signal Y and a chrominance signal C are formed, re-digitized by an analog-to-digital converter 10, and then supplied to a TOI encoder 1 in the same manner as shown in FIG. 3(a). The TCI sub-sampled by the same signal processing as in the basic circuit shown in Figure 3(a) below.
Supplying the signal and the motion vector to the multiplexing circuit 5;1. A digital synchronization signal generated by a synchronization signal generator 11 and an externally supplied audio signal are converted into PCM by an audio PCM circuit 12, and the digital audio signal is multiplexed with a motion vector into a subsampled TOI signal. The multiplexed signal is returned to an analog signal by the digital-to-analog converter 18, and then the microwave is modulated by the 1M modulator 14 and emitted from the parabolic antenna 15 for transmission.

On the other hand, in the receiving side circuit device shown in FIG. After digitizing the signal, the signal is supplied to the separation circuit 6 in the same manner as shown in FIG. 8(b).

The luminance signal Y and chrominance signal 0 extracted by signal processing exactly the same as in the basic circuit shown in FIG. 8(b) below.
The signal is sequentially passed through a digital-to-analog converter 21 and a matrix circuit 22, and is restored to the same three-primary color image signal as the human input on the transmitting side, and then supplied to a color display tube (not shown). Furthermore, the sync signal separated from the received signal by the separation circuit 6 is supplied to the sync signal generator 19 to synchronously generate a sync signal for driving the receiving side device, and the POM audio signal is supplied to the audio POM decoder 20 to provide analog Extract the audio signal.

Examples of specifications of the transmission system of the present invention for transmitting high-definition television signals using the circuit device configured as described above are shown below.

[1] Transmission side light (1) Signal system: Motion compensated multiple sub-sampled TOI signal system (2) Human image signal: 1125 scanning lines, interlace ratio 2:1, field frequency 60 Hz, aspect ratio 5 j 3, R , G, B O, 7Vp.

(3) Signal bandwidth Luminance signal: Stationary part 20 ME (Z
IC moving part 12 MI (Z Color signal...Stationary part 7 MHz % Moving part 8 MI2 (4) Sampling frequency Wi Luminance signal 64.8 MI2.

Color signal 16.2 MI2 (5) TCI baseband bandwidth after time axis compression Approx. 8
MHz (6) Radio frequency modulation method FM, maximum frequency deviation 11 MH2 (7) Carrier frequency 12 GH2 band, occupied bandwidth 27 MHz [2] Receiving side specifications (1) A/D modulation 8 bits, clock frequency 1
1.2 MH2 (2) Signal processing memory 10 Mb The following is an example of reception quality when the transmission method of the present invention is applied to satellite broadcasting.

Satellite transmission output: 100W Estimated reception using a receiving parabolic antenna with a diameter of 1m S
N ratio: 41 dB Problems that still need to be solved in the high-definition television multiplexed subsampling transmission system of the present invention explained above are: (1) Ringing waveform distortion that occurs in the subsampled and transmitted image signal (2) Ringing waveform distortion that occurs in the input image signal Frequency response characteristics during motion image correction The above-mentioned problems can be solved in the transmission system of the present invention as follows.

(1) The restored signal waveform after subsampling the unit function waveform shown in Figure 6(a) at the sample points indicated by circles and transmitting it has ringing at a frequency determined by the transmission bandwidth of the transmission path. occurs as shown in FIGS. 5(b) and (0). If the cosine roll-off characteristics determined by the relationship between the bandwidth of the transmission line that causes such ringing and the sampling frequency match, a state will be obtained in which the center level of the ringing waveform is sampled, as shown in (b) of the same figure. It is possible to reproduce an appropriate unit function waveform regardless of ringing, but if the cosine roll-off characteristics are off, the sample value will change depending on the sample phase as shown in Figure (C), and ringing distortion will occur in the restored waveform. occurs.

In order to remove such ringing distortion occurring in the reproduced signal waveform of the sub-sampled transmission signal, a ringing canceller having a configuration as shown in FIG. 6 is used.

In the illustrated configuration, the analog-to-digital converter 2 receives the restored waveform signal of the sub-sampled transmission signal as an input signal.
3 and also to the phase comparator 25 to control the oscillation of the oscillator 25 based on the result of comparing the phase with the oscillation output clock signal of the voltage controlled clock oscillator 25, as shown in FIG. 5(b). A phase-related sampling clock signal that samples above the center level of the ringing is provided to and driven by the analog-to-digital converter 28. If the digitized reconstructed waveform signal is reconverted by controlling the sampling phase in this way, ringing distortion should be completely removed, but in reality, a slight shift in the sampling phase occurs and ringing distortion remains. . Therefore, in the illustrated configuration, the restored waveform signal in which such ringing distortion remains is supplied to the delay device 27 to be appropriately delayed, and the delay devices 28-1 to 1 pixel delay amount are
28-n cascade connection and coefficient unit 2 connected to each connection point.
A coefficient α is applied to each signal sequentially delayed by 9-θ to 29-n. A transversal filter configured to add and synthesize the signals .about.α□ by the adder 30 forms a ringing waveform signal having a phase opposite to that of the remaining ringing. The ringing waveform signal of the opposite phase is supplied to the subtracter 81 and subtracted from the delayed output restored waveform signal of the delay unit 27 to cancel out and remove the residual ringing distortion.

(2) Noise components included in the vicinity of the sampling frequency of the transmission signal obtained by subsampling the input image signal are folded back and lowered by the band limit of the transmission path, increasing the low frequency nozzle of the transmission signal. In order to prevent such an increase in the number of low frequency nozzles, a band attenuation filter is inserted on the transmitting side to reduce the response near the sample frequency and reduce the noise component that is lowered in frequency due to folding in advance. To substantially prevent image quality deterioration from occurring in a reproduced image. In addition, since the required signal components are also attenuated by the insertion of such a band attenuation filter, a filter that complementarily increases the response near the sample frequency is provided on the receiving side to reduce the signal level of the signal component near the sample frequency. Restore. Note that the response reduction in the vicinity of the sample frequency due to the band attenuation filter inserted on the transmitting side is most preferably set to about 6 (IB).

(8) Each fee is sub-sampled by the method of the present invention,
In order to prevent the generation of false interpolation signals due to image movement when interpolating a motion image thinned out and transmitted for each field using adjacent sample values of adjacent fields, the high-frequency response is reduced in advance on the transmitting side. A filter is inserted, but in order to compensate for the blurring of the reproduced motion image due to such high-frequency restriction, a filter is used whose response characteristic is increased in advance in the mid-range response, which contributes to visually improving the sharpness of the image.

As explained above, in the high-definition television multiplexed subsampled transmission system of the present invention, the TOI image signal that has been subsampled and transmitted is interpolated for each field on the receiving side based on the amount of adjacent samples of the adjacent field. During interpolation, image movement information necessary to control the interpolation mode according to the image movement is sent as a motion vector (transmitted from the eye side together with the subsample TOI signal, but this image movement information is Even without transmission from the transmitting side, it is possible to distinguish and extract sub-sampled transmitted image signals only on the receiving side as follows, and appropriately perform restoration signal processing for still images and restoration signal processing for moving images. Switching can be controlled.

That is, in the transmission system of the present invention, the high-definition television image signal after time-base compression time division multiplexing is subjected to dot subsampling with a four-field period as described above, as shown in FIG. If such subsampling is applied, one image signal will be transmitted in 4 fields, that is, 2 frames, but the spatiotemporal frequency range that can be transmitted in the case of a still image is within the range of A + B shown in Figure 8. Therefore, in the case of a moving image, the spatio-temporal frequency range that can be transmitted is only the range A indicated by diagonal lines in FIG.

Therefore, in the case of a still image, the interpolation of the sample amount of each field thinned out and transmitted by subsampling as described above is as follows. Interpolation of the sample amount marked with / for a frame uses the sample amount transmitted in the previous and subsequent frames as is, and interpolation of the sample amount marked with × uses the sample amount transmitted in the previous and subsequent fields. Use as is. Note that interpolation for such a still image can be performed only by a two-dimensional spatio-temporal interpolation filter having the pass characteristics shown in FIG.

On the other hand, in the case of a moving image, strictly speaking, the amount of samples at the same sample point changes for each successive field or frame, so the amount of samples from adjacent frames or adjacent fields is used as in the case of still images. Interpolation cannot be performed, and interpolation is performed using a two-dimensional space-time filter based only on the amount of samples transmitted for each field. In the case of a moving image, even if such interpolation is performed, the resolution will decrease because the spatio-temporal frequency range that can originally be transmitted is only the range A shown in FIG. The resolution reduction does not cause visual image quality deterioration.

As described above, for moving images, interpolation is performed only on the receiving side based on the two-frame correlation detected mainly from the difference signal between two frames. Examples of the configuration of the side circuit device are shown in FIGS. 9(a) and 9(b), respectively. Note that the interpolation of the sub-sampled transmission signal is performed only on the receiving side, and on the transmitting side, it is only necessary to prevent aliasing distortion components from occurring in the sub-sampled transmission signal. The receiving side circuit device shown in FIG.

In the receiving side circuit device shown in FIG. 9(b), the received sub-sampled transmission signal is stored in four field memo IJ3
7-1 to 37-4 and sequentially delaying each field by one field, at a certain point, four sets of sample quantities in the sub-sampling pattern shown in FIG. ! , 187-1 to 87-4. Note that each field memory 37-1
~87-4 holds only the amount of samples transmitted for each field, so its memory capacity is as shown in Figure 9 (
Field memo IJ 82 of the sender, which will be discussed later regarding a)
A memory capacity of -1 to 32-4 is sufficient.

In such a memory state, first, the field memory 3
7-1 to 87-4 are supplied from both ends of the continuous connection and separated by two frame periods to the motion amount detection circuit 88;
The existence and magnitude of significant image movement is determined according to the degree of correlation between the two frames based on the magnitude of the difference signal between the two frames, and the motion detection output signal is supplied to the mixer 41 and the synthesizer 44 in parallel. , a mixture of interpolation signals for still images and interpolation signals for moving images as described later, which are supplied to each of them.
The ratio of synthesis is changed according to the magnitude of image motion detected based on the magnitude of the correlation between two frames.

Therefore, the mixer 41 has a field memory 87-1.
The sum signal obtained by adding the image signals separated by two frames from both ends of ~87-4 in the adder 40 and multiplying by b, and the one-frame one derived from the intermediate connection point of the frame memories 87-1 to 87-4. Same as the frame-to-frame interpolation signal for still images, which is switched with the frame delay signal at a dot period using the switch SW, the one-frame delay signal from the intermediate connection point of field memo IJ 37-1 to 87-4 is two-dimensionally A frame interpolation signal for a moving image is supplied to an interpolation filter 89 to form an interpolation signal, and for a still image, mutual interpolation of the sample values between the * mark and the O mark in the subsampling pattern shown in Figure 7 is provided. Interpolation is performed by inter-frame interpolation, and for a moving image, mutual interpolation of the sample values of e and O marks is performed using r on the intra-frame interpolation signal.

On the other hand, the synthesizer 44 inputs the mixed output signal from the mixer 41 and the 1-field delayed signal and 3-field delayed signal from each output end of the field memories 87-1 and 37-3 to the two-dimensional interpolation filter 42. An interpolation signal for a still image is supplied and formed, and an interpolation signal for a motion image is formed by supplying the mixed output signal of the mixer 41 to an interpolation filter 48. In the sub-sampling pattern, interpolation is performed on the samples indicated by the X marks based on the sample states indicated by the marks ○1, .

In addition, in the transmitting side circuit device shown in FIG. 9('a), as mentioned above, when interpolation is performed on the receiving side, aliasing distortion components around the sample frequency are not generated. In this way, a two-dimensional low-pass filter 85 is provided for still images, which acts as an anti-airing filter corresponding to the two-dimensional interpolation filter 42 on the receiving side and whose pass region is the spatio-temporal frequency region A+B shown in FIG. A two-dimensional low-pass filter 84 is provided for motion images, which acts as an anti-airing filter corresponding to the two-dimensional interpolation filter 89 and the interpolation filter 48 on the receiving side, and whose pass region is the spatio-temporal frequency region A shown in FIG. field memory 32-1 similar to that on the receiving side.
~2 frames away from both ends of the 82-4 cascade l
2 from the motion amount detection circuit 83 that supplied the +jii image signal.
The mixing ratio of the p-wave outputs of the two-dimensional low-pass filters 84 and 85 by the mixer 86 is changed according to the motion of the image, based on the motion detection output signal based on the two-frame correlation determined by the inter-frame difference signal. let

The two-dimensional low-pass filter 84 is supplied with a one-frame delayed image signal from the field memo IJ 82-2, and the two-dimensional low-pass filter 85 is supplied with one-field delayed image signals from the field memories 32-1 to 82-8. ,l
The motion amount detection circuit 33.0 supplies each image signal with frame delay and 8 field delay. ．． For image motion detection in '38, the absolute value of the low-frequency p-wave output of the difference signal between two frames is enlarged in the time axis direction by a temporal filter using field memory, and the magnitude of the result is used.
The detection operation is stabilized by using a low-pass filter to make it insensitive to detection errors in frame-to-frame difference signals and minute image movements.

In addition, in addition to detecting the amount of image motion by determining the correlation between two frames based on the difference signal between two frames, the amount of image motion is detected by determining the intra-frame correlation based on the difference signal between adjacent fields. Motion detection based on intra-frame correlation The amount of motion detected based on two-frame correlation is used only when the amount exceeds a predetermined level.

(Effect) As is clear from the above description, according to the present invention, different types of narrowband transmission methods can be reliably and easily combined and applied to a wideband high-definition television image signal without mutual interference. As a result, it is possible to compress the band by approximately 3 and perform a significantly narrow band transmission without substantially impairing the high quality of the image, and it can be applied to both digital transmission and analog transmission.

In particular, compared to the similar transmission methods described in connection with the transmission method of the present invention with reference to FIGS. Since the configuration of the side circuit device can be significantly simplified, the present invention is particularly effective as a transmission system for high-definition television satellite broadcasting aimed at a large number of general viewers.

[Brief explanation of drawings]

Fig. 1 is a signal waveform diagram showing the structure of a transmission signal by the time axis compression time division multiplexing ('I'CI) transmission method, Fig. 2 is a diagram showing the operating principle of the sub-sampling transmission method, and Fig. 3 ( a) and (b) are block diagrams showing the basic configurations of the circuit devices on the transmitting side and the receiving side, respectively, in the high-definition television multiplexed subsampled transmission system of the present invention. Block diagrams showing examples of specific detailed configurations of the circuit devices on the transmitting side and the receiving side, respectively. FIG. 6 is a block diagram showing a configuration example of a circuit device for removing ringing distortion in the transmission system of the present invention, and FIG. 7 schematically shows an example of a sub-sample pattern. Figure 8 shows an example of the spatio-temporal frequency response (7) of a two-dimensional low-pass filter used in the transmission system of the present invention.Characteristic curve diagram Figure 9 (, a) and (b) show the transmission system of the present invention 1 is a block diagram showing configuration examples of circuit devices on a transmitting side and a receiving side in a similar transmission method related to 1. TOI enhancer 2. Sub-sample circuit 3. Low-pass filter 4.・Movement information 4tjl
j Output H5...multiplex circuit 6...separation circuit 7...subsample decoder 8...TOI decoder 9.22...matrix circuit 10, 18.23...analog-digital converter 11, 19...Synchronization signal generator 12...Audio POM circuit IL 21...Digital-analog converter 14...
・FM modulators 15, 16... Parabolic antenna 17... FM demodulator 20... Audio POM decoder 24... Phase comparator 25... Voltage controlled clock oscillator 26... Offset adjuster 27 ...delay device 28-
1 to 28-n...1 pixel delay device 29-0 to 29-n.
...Coefficient unit 30.40...Adder 31...Subtractor 32-1 to 82-4.87-1 to 37-4...Field memory 83, 38...Motion amount detector 84, 35... Two-dimensional low-pass filter 36, 41.
...Mixer 89, 42...Two-dimensional interpolation filter 43...Interpolation filter 44...Synthesizer SW...
switch. Patent applicant Japan Broadcasting Corporation

Claims (1)

[Claims] L The luminance signal and color signal of the sampled high-definition television image signal are time-base compressed to form a time-division multiplexed image signal, and the time-division multiplexed image signal is subsampled every predetermined plurality of fields to narrowband. a motion information signal corresponding to the amount of motion of the image represented by the high-definition television image signal is transmitted together with the transmission image signal, and the motion information signal received together with the transmission image signal. The time-division multiplexed image signal is restored by performing interpolation on the narrowband transmission image signal that has been subsampled and converted in accordance with the above, and the luminance signal and color signal of the restored time-division multiplexed image signal are A high-definition television multiplex sub-sampling transmission system, characterized in that the high-definition television image signal is restored by expanding the time axis after separation.