JPS643432B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to an image signal transmission system that narrowbands and transmits a wideband high-definition television image signal, and particularly relates to a narrowband transmission method suitable for narrowband transmission of image signals. It is a combination of systems that allows high-definition television image signals to be transmitted in a sufficiently narrow band.

(Prior art) In recent years, with the advancement of communication technology using geostationary satellites,
Satellite broadcasting technology has also reached the stage of practical use, but in order to effectively utilize satellite broadcasting technology, there is a need to broadcast broadband high-definition television image signals to achieve particularly advanced image information transmission. There is. 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 this, 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 make the high-definition television image signals extremely narrowband and transmit them. However, all of the image signal narrowband transmission methods that have been proposed so far are based on the time axis compression multiplexing (TCI) transmission described later, which is said to have reached the practical level especially in terrestrial image information transmission. If each method or even sub-sampling transmission method is applied independently, it has not been possible to fully put it into practical use for satellite broadcasting of high-definition television image signals.
There was a drawback.

(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. An image signal narrowband transmission system that allows high-definition television image signals to be transmitted in a narrow band sufficient to realize advanced satellite broadcasting using a circuit device with a simple configuration that can be easily combined without interference. In particular, it is an object of the present invention to provide a high-definition television multiple sub-sampled transmission system.

That is, the high-definition television multiplex sub-sampling transmission system of the present invention compresses the luminance signal and chrominance signal of the sampled high-definition television image signal in the time axis to form a time-division multiplexed image signal, and transmits the time-division multiplexed image. The amount of image motion detected from the time-division multiplexed image signal is a sub-sampled output image signal obtained by subjecting the signal to low-pass filtering for still images and low-pass filtering for moving images, and then subsampling each for each predetermined plurality of fields. a narrowband image signal for transmission, and transmits the image signal for transmission in analog form along with a motion vector signal representing uniform motion of the image represented by the high-definition television image signal, and receives the image signal for transmission. The interpolated output image signal is obtained by performing interpolation for still images and interpolation for moving images on the transmission image signal, which has been resampled using a phase-controlled sample clock and has waveform distortion removed by a filter. , according to the motion vector signal received together with the transmission image signal and the motion information signal regarding the amount of motion of the image detected from the transmission image signal, mutually mixing to restore the time division multiplexed image signal; The method is characterized in that after separating the luminance signal and color signal of the restored 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.

In other words, the time axis compression multiplexing (TCI) transmission method is disclosed in, for example, Japanese Patent Application No. 108374 filed by the applicant.
The brightness of a television image signal formed by guiding the primary color image signal captured by a color television camera to a color encoder as described in the patent specification or the patent specification filed on August 30, 1988. Time axis compression is applied to signal Y and color signal C at appropriate ratios, and as shown in Fig. 1, color signal C and luminance signal Y are compressed in time axis during synchronization signal SYNC every 1H horizontal scanning period. It is time-division multiplexed. If the transmission period of the luminance signal Y and chrominance signal C is shifted and transmitted by such time division multiplexing, the bandwidth of each signal itself will be expanded somewhat due to time axis compression, but when narrowband transmission is performed, the normal carrier chrominance signal is Mutual interference between the luminance signal Y and the chrominance signal C, which significantly deteriorates image quality when signals are frequency multiplexed, 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 the specification of Japanese Patent Application No. 58-93358 filed by the applicant, an image signal representing one image is sampled for each pixel point. The values are not transmitted sequentially as they are, but are thinned out and transmitted in a predetermined order for each field over multiple fields, and on the receiving side, samples of adjacent sample points transmitted in the previous and next fields are transmitted for each field. The image for each field is multiplied by interpolating the thinned out sample values with reference to the values. That is, for example, as shown in Figure 2, where sequential sample values are divided into four symbols, sample values thinned out at a four-point cycle are transmitted for each field, and one image is created at a four-field cycle. Complete the transmission of information. Therefore, the amount of information transmitted for each field can be reduced to 1/4, making it possible to perform significantly narrowband transmission. Except for still images that can be restored,
Various proposals have been made in the past regarding interpolation of thinned sample values for a moving image in which sample values at the same sample point change for each field.

As is clear from the above, although both the TCI transmission method and the subsample transmission method are narrowband transmission methods for image signals, they perform signal processing on the same image signal completely unrelated to each other and without mutual interference. obtain. In other words, in the TCI transmission method, by arranging the sample values of the luminance signal and chrominance signal in which the interval between the sample points of each field is narrowed into the front half and the second half for each scanning period, it is possible to transmit only the normal luminance signal. In the same way as transmission, luminance signals and chrominance signals can be transmitted by simply shortening the interval between sample points. On the other hand, the sub-sample transmission method is based on the method of transmitting luminance signals and chrominance signals by simply shortening the interval between sample points. Regardless of this, 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, if interpolation on the receiving side is considered in the same manner as in the past, the TCI 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 between the TCI transmission method and the sub-sampling transmission method to transmit extremely wide-band high-definition television image signals to a significantly narrow band using a circuit device having a relatively simple configuration. It is designed so that it can be digitized and transmitted. That is, in the high-definition television multiple subsampling transmission system of the present invention, after each luminance signal and chrominance signal are sampled and integrated using the TCI transmission system, a motion signal is sampled to control the interpolation of moving parts of the image. In addition to the information signal, interfield and interframe subsampling is performed, and a synchronization signal is multiplexed, and the carrier wave is converted to FM along with the audio signal.
It is modulated and transmitted, and after receiving it, it is decomposed into an image signal, a synchronization signal, and an audio signal.The image signal is subjected to motion compensation and sample amount interpolation, and then separated into a luminance signal and a color signal by a TCI decoder. 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. 3a and 3b, respectively.

In the basic configuration of the transmitting side circuit device shown in FIG.
The TCI signal is generated by time-division multiplexing in the form shown in the first diagram after subjecting each signal to time-base compression. The TCI signal is directly supplied to the sub-sampling circuit 2, and the low-frequency component extracted through the low-pass filter 3 is also supplied to the sub-sampling circuit 2. Furthermore, the TCI signal is supplied to the motion information detection circuit 4, which detects a motion vector indicating the direction and magnitude of the movement of the entire screen of the image represented by the TCI signal using an interframe difference signal, etc., and obtains information on the image movement. It is supplied to the sub-sample circuit 2. In sub-sample circuit 2, the above-mentioned patent application No. 58-93358
As described in the specification, the TCI signal is subjected to subsampling of four field periods as described above with reference to FIG. 2, and the TCI signal subjected to the subsampling is supplied to the multiplexing circuit 5 to generate motion information. The motion vectors from the detection circuit 4 are 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. For still images, the original TCI signal is restored by superimposing the incoming sample values that have been thinned out and transmitted sequentially at 4-field cycles, and for moving images, at 4-field cycles. The sample values of each field thinned out and transmitted are interpolated based on the adjacent sample values of the adjacent fields while referring to the motion vectors that were transmitted together, and the original TCI is approximated.
Restore the signal. Next, the restored TCI signal is supplied to the TCI decoder 8 to extract the luminance signal Y and chrominance signal C, and time axis extension is applied to each of them, and the original luminance signal Y and chrominance signal C are restored to high quality. Plays back 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. 4a and 4b, respectively. As is clear from the drawings, these specific detailed configurations have the form in which necessary circuit devices are added before and after the basic configuration shown in FIGS. 3a and 3b, respectively. That is, in the transmitting side circuit device shown in FIG. 4a, the three primary color image signals R, G, and B obtained as the imaging output of a color television camera are supplied to the matrix circuit 9 to form a luminance signal Y and a color signal C. And analog-
After being digitized by the digital converter 10, the TCI encoder 1 is converted in the same manner as shown in FIG. 3a.
supply to. Below, the subsampled TCI signal and motion vector are supplied to the multiplexing circuit 5 through signal processing exactly the same as in the basic circuit shown in FIG. The audio PCM circuit 12 converts the audio signal supplied from the digital audio signal into PCM and multiplexes the digital audio signal with the motion vector onto the subsampled TCI signal. The multiplexed signal is converted back into an analog signal by a digital-to-analog converter 13, and then modulated into microwaves by an FM modulator 14 and emitted from a parabolic antenna 15 for transmission.

On the other hand, in the receiving side circuit device shown in FIG. Figure 3b
The signal is supplied to the separation circuit 6 in the same manner as shown in FIG. Hereinafter, the luminance signal Y and chrominance signal C extracted by signal processing exactly the same as in the basic circuit shown in FIG. The three primary color image signals are restored and supplied to a color display tube (not shown). Furthermore, the synchronization signal separated from the received signal by the separation circuit 6 is sent to the synchronization signal generator 1.
9 to synchronously generate a synchronization signal to drive the receiving device, and convert the PCM audio signal into an audio signal.
It is supplied to a PCM decoder 20 to extract an analog audio signal.

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

[1] Transmitting side specifications (1) Signal system Motion compensation multiplex sub-sampled TCI
Signal method (2) Input image signal 1125 scanning lines, interlace ratio 2:1, field frequency 60
Hz, aspect ratio 5:3, R,
G, B 0.7V _PP (3) Signal bandwidth Luminance signal: Still part 20MHz, moving part 12MHz, chrominance signal...Stationary part 7MHz, moving part 3MHz (4) Drifting frequency Luminance signal 64.8MHz, chrominance signal
16.2MHz (5) TCI baseband bandwidth after time axis compression Approx.
8MHz (6) Radio frequency modulation method FM, maximum frequency deviation 11M
Hz (7) Carrier frequency 12 GHz band, occupied bandwidth 27 MHz [2] Receiving side specifications (1) A/D quantization 8 bits, clock frequency
11.2MHz (2) Signal processing memory 10Mb An example of reception quality when the transmission method of the present invention is applied to satellite broadcasting is as follows.

Satellite transmission output: 100W Estimated reception using a receiving parabolic antenna with a diameter of 1m SN ratio: 41dB Problems that still need to be solved in the high-definition television multiplex subsampling transmission system of the present invention described above are: (1) Images transmitted after subsampling Ringing waveform distortion that occurs in the signal (2) Folded component noise due to subsamples of noise contained in the input image signal (3) Frequency response characteristics during motion image correction The above-mentioned problems can be solved in the transmission method of the present invention as follows. It can be solved.

(1) The signal waveform restored after subsampling the unit function waveform shown in Figure 5a 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. 5b and 5c. If the cosine roll-off characteristic determined by the relationship between the bandwidth of the transmission path that causes such ringing and the sampling frequency is matched, the ringing waveform will be sampled at the center level as shown in Figure b, and the ringing will occur. An appropriate unit function waveform can be reproduced regardless of the value, but if the cosine roll-off characteristics are off, the sample value will change due to the resampling phase, as shown in c in the same figure, and ringing distortion will occur in the restored waveform. arise.

In order to remove such ringing distortion that occurs in the reproduced signal waveform of the sub-sampled transmission signal, the sixth
A ringing canceller configured as shown in the figure is used. In the illustrated configuration, the reconstructed waveform signal of the sub-sampled transmission signal is supplied as an input signal to the analog-to-digital converter 23, and is also supplied to the phase comparator 24 so as to be connected to the oscillation output clock signal of the voltage controlled clock oscillator 25. The oscillation of the oscillator 25 is controlled according to the result of the phase comparison, and a phase-related sampling clock signal is supplied to the analog-digital converter 23 to sample the center level of the ringing in the state shown in FIG. 5b. so that it can be driven. 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 28- have a one-pixel delay amount.
n cascade connection and signals sequentially delayed by coefficient multipliers 29-0 to 29-n connected to each connection point are multiplied by coefficients α ₀ to α _o , respectively, and are added and synthesized by an adder 30. A ringing waveform signal having a phase opposite to that of the remaining ringing is formed by a versatile filter. The ringing waveform signal of the opposite phase is supplied to the subtracter 31 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 sample frequency in 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 noise of the transmission signal.
In order to prevent such an increase in low-frequency noise, 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 by 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 it is most preferable to set the response reduction in the vicinity of the sample frequency by the band attenuation filter inserted on the transmitting side to about 6 dB.

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

As explained above, in the high-definition television multiplexed subsampled transmission system of the present invention, the TCI 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 adjacent fields. When performing interpolation, subsamples are sent from the transmitting side as motion vectors using the image motion information necessary to control the interpolation mode according to the motion of the image.
Although it is transmitted together with the TCI signal, this image movement information can be determined and extracted from the sub-sampled transmitted image signal only on the receiving side as described below, without being transmitted from the transmitting side. It is possible to appropriately switch and control restoration signal processing and restoration signal processing for moving images.

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 at four field periods as shown in FIG. 7, as described above. If such subsampling is applied, one image signal will be transmitted in four fields, that is, two frames, but the spatiotemporal frequency range that can be transmitted in the case of a still image is the range A+B shown in FIG. In the case of a moving image, the spatio-temporal frequency domain 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 means that the sample amount of the circle point in the subsampling pattern shown in Figure 7 is transmitted. 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 as is. use Incidentally, such interpolation for 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 it is not necessary to use the amount of samples from adjacent frames or fields as in the case of still images. Interpolation cannot be performed, but 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 moving images, even if such interpolation is performed, the spatio-temporal frequency domain that can originally be transmitted is the 8th
Although a reduction in resolution occurs since it is only within the range A shown in the figure, such a reduction in resolution in a moving image does not cause visual deterioration in image quality.

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. An example of the configuration of the device is shown in Figure 9 a and b.
are shown 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. 9b, if the received sub-sampled transmission signal is supplied to the cascade connection of four field memories 37-1 to 37-4 and sequentially delayed by one field, then at a certain point In this case, four sets of sample amounts in the sub-sampling pattern shown in FIG. 7 are held in each memory 37-1 to 37-4 for each successive field. In addition, each field memory 37-1 to 37-4
Since it holds only the amount of samples transmitted for each field, its memory capacity is limited to the field memory 32 on the transmitting side, which will be described later with reference to FIG. 9a.
1/4 of the memory capacity of -1 to 32-4 is sufficient.

In this memory state, first, the image signals separated by two frame periods derived from both ends of the continuous connection of the field memories 37-1 to 37-4 are supplied to the motion amount detection circuit 38, and the magnitude of the difference signal between the two frames is determined. Based on the degree of correlation between the two frames, it is determined whether there is significant image movement or not, and the magnitude thereof is determined, and the motion detection output signal is supplied in parallel to the mixer 41 and the synthesizer 44, and a still image as described later is supplied to each of them. The ratio of mixing and synthesizing the interpolation signal for use with the moving image and the interpolation signal for the moving image is changed depending on the magnitude of the image motion amount detected based on the magnitude of the correlation between two frames.

Therefore, the mixer 41 receives the sum signal obtained by adding the image signals separated by two frames from both ends of the field memories 37-1 to 37-4 in the adder 40 and multiplying the result by 1/2, and the frame memory 37-4. The interpolation interpolation signal for still images is switched at a dot period by a switch SW, and the 1-frame delayed signal derived from the intermediate connection points of field memories 37-1 to 37-4 is connected to the intermediate connections of field memories 37-1 to 37-4. 1 from the point
A frame delay signal is supplied to a two-dimensional interpolation filter 39 to form an intra-frame interpolation signal for a moving image.For still images, the ● marks and ○ marks in the sub-sampling pattern shown in FIG. 7 are supplied.
Mutual interpolation of sample values with the mark is performed by interpolation between frames, and for moving images ●
Mutual interpolation of the sample values between the marks and the O marks is performed using an intra-frame interpolation signal.

On the other hand, the combiner 44 contains the mixed output signal from the mixer 41 and the field memories 37-1 and 37.
The still image interpolation signal formed by supplying the 1-field delay signal and the 3-field delay signal from each output terminal of -3 to the two-dimensional interpolation filter 42 and the mixed output signal of the mixer 41 are interpolated. Filter 4
3, and the interpolation signal for motion images formed by supplying the interpolated signals to the sub-sampling pattern shown in Figure 7. Perform interpolation,
The original image signal, which has been almost completely interpolated, is extracted as the combined output.

In addition, in the transmitting side circuit device shown in FIG. 9a, as mentioned above, when interpolation is performed on the receiving side, the reception A two-dimensional low-pass filter 35 is provided for still images, which acts as an antenna rising filter corresponding to the two-dimensional interpolation filter 42 on the receiving side, and passes through the spatio-temporal frequency region A+B shown in FIG. Dimensional interpolation filter 39 and interpolation filter 43
A two-dimensional low-pass filter 34 is provided for moving images, which acts as an antenna rising filter corresponding to the above, and passes through the spatio-temporal frequency domain A shown in FIG. The motion amount detection output signal based on the two-frame correlation determined by the two-frame difference signal from the motion amount detection circuit 33 which supplied the image signals separated by two frames from both ends of the cascade connection of ~32-4 The mixing ratio of the wave outputs of the dimensional low-pass filters 34 and 35 by the mixer 36 is changed according to the amount of movement of the image. The two-dimensional low-pass filter 34 is supplied with a one-frame delayed image signal from the field memory 32-2, and the two-dimensional low-pass filter 35 is supplied with one-field delayed image signals from the field memories 32-1 to 32-3. It supplies frame-delayed and 3-field-delayed image signals.

In addition, the image motion detection in the motion amount detection circuits 33 and 38 uses the magnitude determination of the absolute value of the low-frequency output of the two-frame difference signal, which is enlarged in the time axis direction by a temporal filter using a field memory. The detection operation is stabilized by using a low-pass filter to make it insensitive to detection errors in the difference signal between two frames and minute movement of the image.

In addition, the two-frame difference signal based on the two-frame difference signal described above is
In addition to detecting the amount of image movement by determining the frame correlation, the amount of image movement is also detected by determining the intra-frame correlation based on the difference signal between adjacent fields, and when the amount of motion detected by the intra-frame correlation exceeds a predetermined level. The motion detection amount based on two-frame correlation is used only for this purpose.

(Effects) 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. , approximately 1/2 times without compromising its high-definition image quality.
It is possible to compress the band to nearly 3 and perform significantly narrowband transmission, 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 that targets a large number of general viewers.

[Brief explanation of drawings]

Figure 1 is a signal waveform diagram showing the structure of a transmission signal using the time-compression time division multiplexing (TCI) transmission method.
The figure is a diagram showing the operating principle of the sub-sample transmission system, and Figures 3a and 3b 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 sub-sample transmission system of the present invention. Figures 4a and 4b are block diagrams showing examples of specific detailed configurations of circuit devices on the transmitting side and receiving side, respectively, and Figures 5a, b,
c is a signal waveform diagram sequentially showing how ringing distortion occurs depending on the sampling clock phase in the sub-sampling transmission method, and FIG. 6 is a block diagram showing an example of the configuration of a circuit device for removing ringing distortion in the transmission method of the present invention. , FIG. 7 is a diagram schematically showing an example of a sub-sample pattern, FIG. 8 is a characteristic curve diagram showing an example of the spatiotemporal frequency response of a two-dimensional low-pass filter used in the transmission system of the present invention, and FIGS. FIG. 1b is a block diagram showing an example of the configuration of circuit devices on the transmitting side and the receiving side in a similar transmission system related to the transmission system of the present invention. 1...TCI encoder, 2...Subsample circuit, 3...Low pass filter, 4...Motion information detector, 5...Multiple circuit, 6...Separation circuit, 7...
Subsample decoder, 8...TCI decoder,
9, 22... Matrix circuit, 10, 18, 23
...Analog-digital converter, 11, 19...
... Synchronization signal generator, 12 ... Audio PCM circuit, 1
3, 21...Digital-to-analog converter, 14
...FM modulator, 15,16...parabolic antenna, 17...FM demodulator, 20...audio PCM
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 device, 30,
40...Adder, 31...Subtractor, 32-1 to 3
2-4, 37-1 to 37-4... Field memory, 33, 38... Motion amount detector, 34, 35...
...Two-dimensional low-pass filter, 36, 41... Mixer, 39, 42... Two-dimensional interpolation filter, 43...
...Interpolation filter, 44...Synthesizer, SW...Switch.

Claims (1)

[Claims] 1. 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 subjected to still image low-pass filtering. The sub-sampled output image signals are subjected to low-pass filtering for moving images and then sub-sampled for each predetermined plurality of fields, and are mixed with each other according to the amount of movement of the image detected from the time-division multiplexed image signal. a sample clock that forms a transmission image signal in a high-bandwidth band, transmits the transmission image signal in analog form together with a motion vector signal representing uniform movement of an image represented by the high-definition television image signal, and receives and controls the phase of the transmission image signal; Receive interpolated output image signals obtained by performing still image interpolation and moving image interpolation on the transmission image signal, which has been resampled and waveform distortion removed by a filter, together with the transmission image signal. The time-division multiplexed image signal is restored by mixing the motion vector signal and the motion information signal regarding the amount of motion of the image detected from the transmission image signal, and the restored time-division multiplexed image signal is A high-definition television multiplex sub-sampling transmission system characterized in that the high-definition television image signal is restored by separating a luminance signal and a chrominance signal and then extending the time axis of each.