SU1117861A1 - Device for transmitting and receiving several broadcast programs via single conventional televison channel - Google Patents

Abstract

A DEVICE FOR TRANSMITTING AND RECEIVING MULTIPLE PROGRAMS ON A SINGLE STANDARD TELEVISION CHANNEL, containing in the transmitting part N sources of television programs, a tag generator, a switch and a transmitter, and in the receiving part a processing unit of a high-frequency signal, a block of the selected program, combinantly combined, programmed, combinantly combined, combined, combined, combined, combined, combined, combined, combined, combined, combined, combined, combined, combined, combined, combined, connected to the selected program, the unit of the selected program, combinantly connected into the program, combines, consecutively combined, combines, consecutively connected but not used, combined, combined. and a playback unit, characterized in that, in order to increase the image quality by taking into account the statistical properties of the images of various programs, in the transmitting part There are N memory blocks, an addressing block and a priority block, each of the N outputs of the tag generator are connected to the input of the corresponding TV program source, whose outputs are connected to the input of the corresponding memory block whose outputs are connected to the inputs of the switch and the priority block whose output connected to the control input of the switch, the output of the addressing block is connected to the address inputs of the memory blocks and the priority block, and the output of the switch is connected to the input of the transmitter, and in the receiving part the processing block. ochastotnogo signal (A vscheleni selected program unit and the switch are connected in series, the input switch information is combined with the clock reproducing bdoka and connected to the output of the high frequency signal processing unit, and upralzl kntsyy vhodd switch is integrated with the control input of the memory unit. "H 00 9d

Description

I

The invention relates to television and can be used in broadcast television systems.

A device comprising, on the transmitting side, serially connected a first signal switch, a low-pass filter, a modulator and an adder, the second input of which is connected to the second output of the first switch and integrated with the input of the second low-pass filter is known. The signals from the output of the adder and the second output of the switch arrive at the second switch, the output of which is connected to the transmitter. At the receiving side, there is a system that provides frequency selection, as well as memory blocks, which ensure the reproduction of the signal of this program at time intervals when another program lj is being transmitted.

However, the device is cumbersome and complicated on the receiving side, which is unacceptable in broadcast television, where maximum simplicity of the receiving device is required. In addition, the device, by virtue of the principle of operation, does not take into account static communications in television signals of different programs, which, in turn, does not allow the signal to be multiplexed by a large number of programs while maintaining the required quality.

I

The closest to the invention in its technical nature is a device for transmitting several programs on one standard television channel, containing in the transmitting part N sources of television programs that have keys that have control inputs connected to the switch, and a filter connected to the mixer, the other inputs of which are connected to the tag generator and the transmitter, and in the receiving part of the high-frequency signal processing unit, the selection unit of the selected program, serially connected mutator, memory and playback unit 2 | .

However, the combination of programs in the known device occurs without taking into account the degree of dynamism of the image of the NIL, i.e. does not wipe out statistical links in television signals 1178612

different programs, which causes a reduction in the quality of transmission in terms of traffic contiguity.

The purpose of the invention is to increase the quality of fair images by taking into account the statistical properties of images of various programs.

The goal is achieved by the fact that in the device for transmission

10 and receiving several programs on one standard television channel, containing in the transmitting part, N sources of television programs, a tag generator, a switch

fS and transmitter, and in the receiving part a high-frequency signal processing unit, a block from the selected program, a switch connected in series, a memory block

20 and a playback unit, N blocks of memory, an addressing block and a priority block are entered into the transmitting part, each of the N outputs of the tag generator being connected to the input of the corresponding television program source, the outputs of which are connected to the input of the corresponding memory block whose outputs are connected to the inputs of the switch and the priority block, the output of which is connected to the control input of the switch, the code of the addressing block is connected to the address inputs of the memory blocks and the priority block, and the output of the mutator is connected to the input before At the receiving unit, and in the receiving part of the high-frequency signal processing unit, the selected program selection block and the switch are connected-sequentially, the information input of the switch is combined with the synchronous input of the playback unit and connected to the output of the high-frequency signal processing block, and the control input of the switch is combined with the control the inputs of the memory block.

FIG. 1 shows a structural electrical circuit of the device; FIG. 2 - the same, priority block

50 in FIG. 3 is the same, the comparison unit included in the priority block in FIG. 4 - diagrams that show the operation of the device.

The device contains a generator 1

55 tags, which can consist of N formers 1-1, 1-2, ..., 1-N tags, N sources -2 television program, analog-to-digital converter (ADC) 3, N blocks of 4 and 5 mi, priority block 5, switch 6, digital-to-analog converter (D / A converter) 7, transmitters 8, addressing block 9, high-frequency signal processing block 10, including selector 11, intermediate frequency amplifier 12 and video detector 13, selected-program selection block 14, including decoder 15 and control block 16, switch 17, memory block 18, fulfilled, for example, as a follower ICP 19 connected to, random access memory 20 and DAC 21, the block 22 product of howling comprising chrominance block 23, video amplifier 24 and sweep unit 25 connected to the respective inputs of the kinescope 26. The apparatus operates as follows. Each of the sources of 2 television programs generates a complete video signal, marked with its own label. The tag can be a binary number in a sequential code, entered on the frame damping pulse and allows the signal of the selected program to be selected on the receiving side. The signals taken from the outputs of sources 2 are converted into digital form by ADC 3 and entered into memory blocks 4, the capacity of which must be at least two frames, which allows for analyzing the changes of the elements from frame to frame. Priority unit 5 makes an LIZ of changes in image elements for each program and sends a command to transmit to the channel the signals of the program that is subject to more changes at a given moment. The priority block (Fig. 2 contains 5 identical channels containing successively connected comparison block 27 and a storage counter 28. The counter outputs are connected to the inputs of the arithmetic-logic block 29. The priority block 5 operates as follows. From the outputs of memory blocks 4 Binary numbers are characterized, characterizing both the luminance and chrominance characteristics of each picture element. These numbers, which are not less than eight in size, are successively compared in comparison block 27, and the number of elements changed. In the next two frames (half-frames), the accumulator is counted during the frame by the counter-accumulator 28. As a result, in each of the counters 28 at the end of the frame there are numbers that characterize the degree of image change for each of the tiporpaMM. and according to the results of the comparison, a command is developed which provides switching to the output of the switch 6 of the program where there are more changes. Then the signal is converted into analog form by means of the DAC 7 and transmitted by transmitter 8 to a nd. FIG. 3 shows a variant of the block diagram of the comparison unit 27. It may contain an additional code shaper 30, an adder 31, an OR element 32 and an AND 33 element. The additional code shaper 30 and a adder form a subtraction device. As a result, at the output of the adder, a number appears that is equal to the difference of the input numbers, which characterize the corresponding pair of elements of two frames. The OR element 32, connected to the outputs of several high-order bits, ensures the output of the signal of a logical unit as soon as the difference exceeds a certain pre-determined number determined by the number of these high-order bits. Thus, with a slight difference in the two compared elements, there is no signal at the output of the element OR 32. Otherwise, this signal, gated in order to eliminate false alarms on the element And 33, passes to the input of the drive counter. 28. As a result, the TV / NAL input to the receiving part contains a mixture of N TV signals. FIG. 4a shows an example of such a signal with N 4. This example shows that the plot in the program numbered 1 most often, and most rarely in the program numbered 3. This signal is fed to the input of the high-frequency signal processing unit

The signal arrives at the decoder 15 from the output of the video detector 13 which enters it. Depending on the program control selected by block 16, the decoder 15 selects the resolution signal only when a frame with the selected program is transmitted.

FIG. 46 illustrates the operation of the decoder in the program selection mode at number 1. The frame identification of each program is performed by decoding the tag entered on the transmitting side using the tag generator 1, comparing the received number with the introduction to the decoder 15 by means of control block 16. Under the action of the output signal of the decoder 15, the switch 17 is unlocked every time (Fig. 4c), when the signal of the selected program is transmitted, providing an update of the information stored

one.

6 by the memory block 18. In addition, the output signal of the decoder provides for the inclusion of the memory block 18 in the recording mode. A / D converters 19 and D / A converters 21 provide analog-to-digital and broadband analog signal conversion required for operation of a discrete random-access memory. B-case of analog

the memory unit does not need these conversions.

The signal is then fed to video amplifier 24 and chrominance block 23, where the usual signal processing is performed in order to obtain an image on the screen of a kinescope,

The technical and economic efficiency of the invention in comparison with the known device consists in increasing the quality of the image by more often transferring the frames of the program in which the image is changed to a greater degree.

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Claims (1)

DEVICE FOR TRANSMISSION AND RECEIVING OF SEVERAL PROGRAMS ON ONE STANDARD TELEVISION CHANNEL, containing in the transmitting part N sources of television programs, a tag generator, a switch and a transmitter, and in the receiving part a high-frequency signal processing unit, a selector program allocation unit, a memory unit connected in series with and a playback unit, characterized in that, in order to improve image quality by taking into account the statistical properties of the images of various programs, N b are introduced into the transmitting part locks of memory, an addressing block and a priority block, each of the N outputs of the label generator connected to the input of the corresponding source of the television program, the outputs of which are connected to the input of the corresponding memory block, the outputs of which are connected to the inputs of the switch and the priority block, the output of which is connected to the control input switch, the output of the addressing unit is connected to the address inputs of the memory blocks and the priority block, and the output of the switch is connected to the input of the transmitter, and in the receiving part the processing unit is. the signal input unit of the selected program and the switch are connected in series, the information input of the switch is combined with the sync input of the playback unit and connected to the output of the processing unit of the high-frequency signal, and the control input of the switch is combined with the control input of the memory unit. >