SU1555918A1 - Device for reproduction of video signal - Google Patents

Abstract

The invention relates to radio engineering. The purpose of the invention is to expand the functionality. The device for reproducing a video signal contains ADC 1, blocks 2 and 20 of line selection, counter 3 of the line's lines, counter 4 of the mark length, switch 5 clocking pulses, trigger 6, block 7 for selecting the display area, block 8 for comparing codes, mixer 9, video control block 10, synchronizers 11 and 16, phased gums 12 and 17 pulses, frequency dividers 13 and 18, switch 14, decomposition standard converter 15, memory block 19 and control block 21. This device allows you to play video signals of various decomposition standards on the screen of a video monitor unit of a fixed standard, since provides a change in the time scales of the signals by recording, taking into account the parameters of the decomposition standard, and reproduction - with the required fixed frequency. The goal is achieved by ensuring the reproduction of the video signal of television systems having different decomposition standards. Given il. performing blocks 2 and 20 allocations, a counter 3, a block 7 of choice, dividers 13 and 18, a block 19 of memory and a block 21 of control. 12 il.

Description

ate ate ate

with

00

unit, code comparison unit 8, mixer 9, video control unit 10, synchronizers 11 and 16, phased heads 12 and 17 pulses, frequency dividers 13 and 18, switch 1, converter 15, decomposition standards, memory unit 19 and control unit 21. This device allows you to play video signals of various decomposition standards on the screen of a video monitor unit of a fixed standard, since provides change

the time scales of the signals due to the recording, taking into account the parameters of the decomposition standard, and the reproduction - with the required fixed frequency. The goal is achieved by ensuring the reproduction of the video signal of television systems having different decomposition standards. Given il. performing blocks 2 and 20 allocations, a counter 3, a block 7 of choice, dividers 13 and 18, a block 19 of memory and a block 21 of control. 12 il.

The invention relates to means of monitoring and measuring the parameters of a television signal, in particular, means of displaying a video signal waveform on a screen of a video monitoring unit.

The purpose of the invention is to enhance the functionality by reproducing the video signal of television systems having different decomposition standards.

FIG. 1 shows a block diagram of a device for reproducing a video signal; in fig. 2 is a block diagram of the control unit; in fig. 3 is a block diagram of a first row allocation unit; in fig. - block diagram of the second block line selection; in fig. 5 is a block diagram of a display zone selection unit; FIG. 6 is a block diagram of a row element count; in fig. 7 structure of the first frequency divider; in fig. 8 is a block diagram of a second frequency divider; at aig. 9 is a block diagram of a memory unit; in fig. 10 is a timing diagram of the operation of the first line selection unit; in fig. 11 - the image on the screen of the video monitoring unit and the parameters of the standard decomposition of this unit; in fig. 12 — Parameters of the standard for decomposition of the video signal under investigation.

A device for reproducing a video signal (Fig. 1) contains an analog-to-digital converter 1, a first line selection block 2, a line element counter 3, a mark length counter 4, a clock switch 5, a trigger (U, display zone selection block 7, comparison block 8 to

five

about

five

0

five

0

Dow, mixer 9, video monitor unit 10, first synchronizer 11, first phased pulse generator 12, first frequency divider 13, switch 14, decomposition converter 15, second synchronizer 16, second phased pulse generator 17, second frequency divider 18, memory block 19 ti, second line selection unit 20 and control unit 21.

The control unit 21 (FIG. 2) comprises a keyboard 22, a computing device 23, an indication device 2k, and a decoder for the 25 recording signals.

The first block of line selection 2 (Fig. 3) contains a parallel register 26, a counter of 27 lines, a first 28, a second 29 and a third 30 triggers, a delay pulse generator 31, an inverter 32, a switch 33, and AND 34.

The second block of line selection 20 (FIG. 4) contains a parallel register 35, a counter of 36 lines, a first 37, a second 38 and a third 39 flip-flops, a delay pulse shaper 40, an inverter 41, a switch 42 and AND 43.

The display zone selection unit 7 (Fig. 5) contains a parallel register 44, a first counter of 45 rows, a second counter of 46 rows and a trigger 47.

The counter 3 row elements (FIG. 6) contains a parallel register 48 and a counter 49. The first frequency divider 13 (FIG. 7) contains a parallel register 50, the first 51 and the second 52 counters. The second frequency divider 18 (FIG. 8) contains a parallel register 53 and a counter 54.

Memory unit 19 (FIG. E) contains a first switch 55, a second switch 56, a parallel register 57, an adder 58, an address counter 59, and a memory 60.

The device for reproducing a video signal has three modes of operation: recording and reproducing a video signal of a television system having the same decomposition standard (first standard) as the video control unit 10, recording and playing back the entire selected video signal line of a television system having a standard decomposition (second standard), different from the first standard, the reproduction of a defined part 61 of the video signal recorded in the second mode with a defined label 61 (FIG. 1).

The first decomposition standard is characterized by the following parameters (Fig. 11): the number of lines N, in the field (or frame for line-by-line decomposition by the number of raster elements M, in ke, the number of the selected line n, scrap of raster elements t, from the beginning

str

the selected line before the beginning of the image of the label 61, the number of raster elements L, in the image of the label 61. The second decomposition standard corresponds to the same parameters Na,

M, pg, m2, L2 (Fig. 12).

When operating in the first mode, the input video signal from input 62 through the switch 14 is fed to the input of the first synchronizer 11, from the first output 63 of which the lowercase extinguishing SGI pulses are removed, and from the second output 6k - damping pulses of the PGI, providing synchronous operation, device blocks. After turning on the first mode of operation, the computing device 23 executes the setup program for the initial state of the controlled blocks. At the same time, the first block selection line 2 receives the command Bt, which determines the starting address of the selected line and the number of the sex in the frame. The display area selection unit 7 receives the command S, setting the initial position of the display area. The first divider 13 of the frequency receives the command K ,, determining the initial division factor, the counter 3 elements of the line - the command t, setting the initial position of the label image, in block 19 of the memory - the command R ,, switching-

five

ten

to j

20

schA this unit to work in the first mode.

The command B is written into the parallel register 26 (input 65) of the first block 2 line selection (Fig. 3) by the signal from the output 66 of the decoder 25 of the recording signals. Team B code, consists of two information parts. In the first part, the code of the number of the selected line n, is transmitted. The size of this part B is determined by the maximum possible value of Hz, i.e. N. In the second part of B1, which occupies one bit of the command code, the code is transmitted.

This code is given in 1, defining one of the two fields of the first decomposition standard.

During the retrace across the field, the impulse of the URI, rewrites 27 lines (input 64) of the first block 2 of the line selection code n, from the first output of the register 26. After the receipt

numbers floor P (in the frame, it takes the value or

thirty

25 to the subtracting input of the counter 27 (input 63) n of the GIS pulses; the signal from the counter transfer output sets the first flip-flop 28 to state 1. The next GHI pulse returns the flip-flop 28 to the output of this flip-flop and a pulse of the selected row is generated.

The choice of gender is as follows. In the first field, the decline of the PGI pulse (Fig. Yua) is ahead of the SGI pulse, (Figure 106) by half the duration H of the SGI sequence (. As the PGI drops, the driver of the delay pulse 31 is triggered, which gives a pulse with a duration of 0.5N (Figure 10c By the decay of the delay pulse, information is recorded in the second 29 and third 30 triggers on their D inputs. On the D input of the second trigger 29, the MHI pulses ((Fig. 106) arrive after passing through the inverter 32. Therefore, on D- the input of the trigger 29 at the time of the decline of the delay pulse presence35

40

45

logical level 1 and three are in place (- ger 29 is set to state 1 (Fig. South).

In the second field, similarly, the third trigger 30 is set to state 1 (Fig. Yod). At the end of each field, triggers 29 and 30 return to state O by a PIP pulse. Through the switch 33, the controlled code P, from the second output of register 26, the pulses of the first or second field, removed respectively from the outputs of the flip-flops 29 and 30 (Fig. South, e), pass to the first input of the AND element 34. To the second input of the AND element 34 pulses are output from the trigger output 28. The pulses of the selected line are removed from the output of the AND 34 element (output 67) in the field defined by code P,.

Command S is written in parallel register 44 (input 65) of display area selection unit 7 (Fig. 5) by a bus from the output 68 of the decoder 25 CHI recording channels of control unit 21. The command code S corresponds to the line number fs of the raster of the first decomposition standard from which the display zone begins. In the initial position, the trigger 47 is in the state O. The output signal of the trigger 47 is fed to the reset input of the second counter of 46 lines and keeps this counter in the state O. During the return stroke across the field, the PIP pulse rewrites 45 rows in the first counter (input 64 a) S code from register output 44. After the first counter of 45 lines (vcode 63) S arrives at the subtractive input, the pulses of the GIS are sent / the signal from the transfer output of this counter sets the trigger 47 to state 1. At the same time, the second counter of 46 lines with capacity is enabled equal to the number of level s quantization Q input video signal to an analog-digital converter 1. After arrival at the summing input of the second counter 46 lines (input 63) Q GIS pulse signal output from the transfer this counter returns

20

25

35

40

trigger 47 to O1 state

During the operation of the 46 second row counter, a parallel binary code is removed from the output 69 of block 7, which varies from zero to Q and corresponds to the rows of the display area. The 45 K1 command is written to the parallel register 50 (input 65) of the first frequency divider 13 (FIG. 7) a signal from the output 70 of the decoder 25 of the recording signals of the control unit 21. The command code K corresponds to the division factor of divider 13. During the return stroke on the line, the MHP pulse (input 63) resets the first 51 and second 52 counters of the output of the first phased generator 12 pulses. After the reset, the first pulse of frequency F causes a signal at the transfer output of counter 51 (output 71) of the signal, which is fed to the pre-recording input of this same counter and rewrites it

50

code K, with the output of the register 50. in the counter 51 K.

After

arrival frequency

h

 impulse code K, again brings

with at counter 51, etc. Frequency F.

t, 71

clocking pulses at the output of the first divider 13 in K / times lower

frequency f,. The first pulse after frequency F, causes the appearance at the transfer output of counter 52 (out 72) of a signal, which is fed to the prerecord input of this counter and rewrites the division factor code K0 into it. This code is fed to the information input 73 of the counter 52 in the form of a fixed subscriber O and 1. The counter 52 operates in the frequency division mode F (similarly to the counter 51.

From the output 72 of the first divider 13 frequency, the frequency pulses of the ra ra elements, the first hundred decay decomposition, are removed. The frequency of F34 is K times lower than the frequency of F ,. The command t is written into the parallel register 4 (input 65) of the counter 3 elements of the string (Fig. 6) by the output 74 of the encoder 25 of the recording signals of the control unit 21. The command code n corresponds to the number of raster elements from the beginning of the line to the beginning of the image or a label. During the return stroke, the TPS ,, pulse rewrites the code 49 into the counter 49, from the output of the register 48. During the forward run on the page, the frequency of the raster pulses is sent to the subtracting input of the counter 49

elements F3f (input 72). After passing to the 49 p counter, the frequency pulses F3 (at the transfer output of the counter (output 75), a signal is generated that determines the position of the label.

The signal is generated by the tag as follows. In the absence of a pulse of the selected line, the signal level, available at the output 67 of the first block of line selection 2, is

ki of the first divisive state.

During the forward stroke of the line, the subtractive inputs of counters 51 and 52 are received by frequency pulses F, s

13 frequencies at the zero setting input

 6 and holds it in state O. During the pulse of the selected line, trigger 6 is enabled, and the pulse of the beginning of the mark from output 75 is counted

the output of the first phased generator 12 pulses. The first after the reset pulse frequency F, causes the appearance at the transfer output of the counter 51 (output 71) of the signal, which is fed to the pre-recording input of the same counter and rewrites it

code K, with the output of the register 50. in the counter 51 K.

After

arrival frequency

h

 the pulse code K is again stored in the counter 51, and so on. Frequency F.

t, 71

clocking pulses at the output of the first divider 13 in K / times lower

frequency f,. The first pulse after frequency reset F causes the signal at the transfer output of counter 52 (output 72) of a signal that is fed to the pre-entry input of the same counter and rewrites the division coefficient code K0 into it. This code is fed to the information input 73 of the counter 52 in the form of a constant set of logical O and 1. The counter 52 operates in the frequency division mode F (similar to the counter 51.

From the output 72 of the first divider 13 frequency, the frequency pulses of the ra ra elements, the first standard of decomposition, are removed. The frequency of F34 is K times lower than the frequency of F ,. The command t is written into the parallel register 48 (input 65) of the counter 3 row elements (FIG. 6) by the output 74 of the decoder 25 of the recording signals of the control unit 21. The command code n corresponds to the number of raster elements from the beginning of the line to the beginning of the image of the label. During the return stroke on the line, the pulse of the OIG ,, rewrites the code 49 into the counter 49, from the output of the register 48. During the forward stroke along the line, the raster frequency pulses go to the subtracting input of the counter 49

elements F3f (input 72). After passing to the counter 49 p, the i-frequency pulses F3 (at the transfer output of the counter | output (output 75), a signal is generated that determines the position of the label.

The formation of the tag signal occurs as follows. In the absence of a pulse of the selected line, the signal level, which exists at the output 67 of the first block 2 of the line, is fed to the input of the installation O of the trigger

6 and holds it in the state O. During the pulse of the selected row, the operation of the trigger 6 is enabled, and the pulse of the beginning of the mark from the output 75 of the score 10

20

915559

The mic of 3 line elements sets the trigger 6 to state 1. At the same time, the output of trigger 6 removes the tag signal, which is fed to the third input of the mixer 9 for displaying on the screen of the video control unit 10. The tag signal is also fed to the control input of the switch 5 of the clock pulses, by allowing the switch to output 76 of the switch 5 clocking pulses of the FT frequency from the output 71 of the first divider 13 frequency. The clock pulses of the FT frequency from the output 76 of the switch 5 are fed to the clock input of the counter length marker k, the capacity of which is equal to the number of raster elements M, in the line of the first decomposition standard. The counter is set to the zero state at the beginning of each row by the pulses of the OIG, from the output 63 of the first synchronizer 11.

After passing to the 4 M counter, the FT frequency pulses the overflow signal from the 77 output of this counter arrives at the trigger synchronization input of trigger 6 and sets it to the O state, since the D level input of the trigger 6 sets the logic level O. label signal -, Q ends. The duration of the tag signal decreases with increasing frequency FTl, i.e. with a decrease in the division ratio k ,. At FT (equal to F3i. The duration of the label signal is equal to the forward duration of the selected row of the first decomposition standard. The R command is written into parallel register 57 (input 65) memory blocks 19 (FIG. 9) with output 66 from decoder 25 signal recording unit 21 control.

Team code R, consists of four information parts g ,, - Гч. The code in the R command carries zero information, which from the output 78 of the register 57 enters the information input of the adder 58. The code d4 controls the operation mode of the adder 58, including it for summing numbers (MF mode) or pass-through transmission (SP mode). In the MF mode, the adder 58 sums the numbers set at its first (input 78) and second information inputs. In the SP mode, the code set at the first 55 input of the adder is transmitted to the output of the adder. The code fi is fed to the control input of the adder 58 from the output 79 of the register 57. In the first mode

40

0

0

59

5 Q

0

1810

operation of the video playback device, the adder 58 is not used and can be turned on at the SP or MF.

The code r3 defines one of the three states of the first switch 55. The first state - to the outputs 80-82 of the switch 55 passes signals respectively from its inputs 67, 63 and 7 &J; the second state - to the outputs 80-82 of the switch 55 pass t signals, respectively, from its inputs 83-85J, the third state — the outputs 81 and 82 of the switch 55 pass signals, respectively, from its inputs 63 and 76, and output 80 is turned off. The code r is fed to the control input of the first switch 55 from the output 86 of the parallel register 57. In the R command, the code r determines the first state of the switch 55.

The g $ code defines one of the three states of the second switch 56: the first state — the outputs 87 and 88 of the switch 56 pass signals respectively from its inputs 82 and 81, and the output 89 is turned off; the second state — the outputs 89 and 88 of the switch 56 are passed to signals respectively from its inputs 82 and 81, and the output 87 is turned off; the third state - the outputs 87 and 89 of the switch 56 pass signals, respectively, from its inputs 82 and 81, and the output 88 is turned off. The code r is applied to the control input of the second switch 56 from the output 90 of the parallel register 57. In the R command, the rms code determines the first state of the switch 56.

Video recording and playback in the first mode of operation occurs as follows. The impulse of the selected line from the output 67 of the first block 2 of the line is fed to the sixth input of the memory block 19 (input 67) through the first switch 55 is fed to the input 80 of the control write-read drive 60 and sets the write mode of the drive. The clock pulses of the FT frequency from the output 76 of the switch 5 of the clock pulses during the pulse of the selected row are fed to the seventh input of the memory unit 19 (input 76) and passed through the switches 56 and 55 to the summing input of the address counter 59. In this case, the address input of the accumulator 60 from the output of the counter 59 of the address is received

eleven

an address code varying from zero to a value of M ,.

The zero state of the counter 59 is set at the beginning of each row by pulses of GIS, which from output 63 of the first synchronizer 11 are fed to the fifth input of memory block 19 (input 63) and through switches 56 and 55 arrive at the reset input of the address meter 59. Moreover, the clock pulses of the frequency FTl from the output 82 of the first switch 55 are also fed to the clock input of the analog-digital converter 1 (input 82) and the clock input of the accumulator 60 for recording into the accumulator of video signal samples received from the information output 91 of the analog-digital converter 1 to the input of the storage device 60 (entry 92).

After the end of the pulse of the selected row, the accumulator 60 switches to the readout mode. The reading occurs at a frequency F3, the pulses of which from the switch output 76 of the switch 5 clock pulses pass through the switches 56 and 55 of the memory block 19 to the summing input of the address counter 59. Video signal samples from the output

drive 60 is fed to the second input of the ROM mode from the keyboard 22 to the calculus35

40

block 8 comparison of codes (input 92) in the form of parallel binary codes. A binary parallel code from the output 69 of the display area selection unit 7 is supplied to the first input of the code comparison unit 8.

During each line of the display area, the codes of all M, samples are successively compared in block 8 with the output code of block 7, which is the number of this line. When these codes coincide, a signal is generated which, from the output of the code comparison unit 8, via mixer 9 enters the video monitoring unit 10 and forms on its screen an oscillogram 93 of the video channel under investigation (Fig. 11). Simultaneously with the waveform, the image 61 of the mark is reproduced.

Selection of the line, changing the position on the line of the label and its length (selection of the required line segment) is performed using the keyboard 22 of the control unit 21 by calling programs that reduce or increase the values of n, mf, Kr. When the length of the label decreases, the frequency FTi video input signal sampling is increased, which allows to reproduce video signals

45

50

The control unit 23 of the control unit 21 enters the number of the second mode of operation and the parameters of the second decomposition standard in which the television system operates: the number of lines N2 in the field, the number of raster elements Mg in the line, the number of field Ry in the frame, the frequency F5l of the solvent elements , the number of the selected line

The second mode of operation is divided into two stages: recording and playing back the video signal of the entire selected line. To do this, after starting the second mode from the keyboard 22, the computing device 23 executes the program for setting the controlled blocks to the required states. This program is executed when the first and second interrupt requests are denied to the inputs 83 and 9k of the computing device 23. At the same time, the first command B4 is written to the first line selection block 2, indicating the number n of the selected line and the number of the first field P (, in the first decomposition standard. Record of command B is the same as the first operation mode. In this command, the Hz number of the selected

55918

12

ten

with great precision. In all modes of operation of the device for video playback, the display area is automatically located in that half of the screen of the video monitoring unit 10 (upper or lower) f in which the selected line is not located. For this, the computing device 23 of the control unit 21 programmatically determines the position of the selected line on the raster and is recorded in the display zone selection unit 7 corresponding value S.

In the first mode of operation, the update of information in memory block 19 occurs during each pulse of the selected line. In the second mode of operation, the device for reproducing the video signal 20 operates as follows. The output of the decomposition standard converter 15 is connected with the switch Ik to the input of the first synchronizer 11. In this case, the image to which the input video signal of the second decomposition standard at input Jk corresponds corresponds to, after conversion to the first standard, is played by the video monitoring unit 10.

25

o rum mode with keyboard 22 in comput5

0

five

five

0

The control unit 23 of the control unit 21 enters the number of the second mode of operation and the parameters of the second decomposition standard in which the television system operates: the number of lines N2 in the field, the number of raster elements Mg in the line, the number of field Ry in the frame, the frequency F5l of the solvent elements , the number of the selected line

The second mode of operation is divided into two stages: recording and playing back the video signal of the entire selected line. To do this, after starting the second mode from the keyboard 22, the computing device 23 executes the program for setting the controlled blocks to the required states. This program is executed when the first and second interrupt requests are denied to the inputs 83 and 9k of the computing device 23. At the same time, the first command B4 is written to the first line selection block 2, indicating the number n of the selected line and the number of the first field P (, in the first decomposition standard. Record of command B is the same as the first operation mode. In this command, the Hz number of the selected

. 155

strings are defined as follows:

li N

(one)

Such a determination of the number of the selected line p allows the position of the selected line in the second standard to be estimated from the transformed image of the second standard on the screen of the video monitor unit 10. The value of N, in formula (1) is constant and stored in the memory of the computing device 23. In the first the frequency divider 13 receives the code of the division factor K ,, equal to K0: the length of the image 61 marks on the screen of the video monitor unit 10 (Fig. 11) is set equal to the length of the image of the active part of the string of the first standard decomposed . In the counter of 3 elements of the line, the value of ha is equal to zero, which corresponds to the coincidence of the beginning of the image of the 61 marks with the beginning of the line. The value S supplied to the display zone selection unit 7 is determined by the computing device 23 in the same way as in the first mode of operation. The second frequency divider 18 receives the command K, the code of which indicates the division factor of the divider 18. The magnitude of K is determined as follows:

TO

where F2 is the frequency of the second phased

pulse generator 17; GE1 is the frequency of the raster elements of the second decomposition standard;

k is a constant coefficient. The value of k can be entered from the keyboard 22 or permanently stored in the memory of the computing device 23 and shows how many times the sampling frequency when analog-to-digital conversion of the video signal of the second decomposition standard should be higher than the frequency 731. This is necessary to increase the detail when playing the video signal.

The input video signal is fed to the input of the second synchronizer 16, from the output 8 of which the horizontal damping pulses of the GIS are removed, and from the output

five

; 918

AND

her

-

15

9 - damping pulses of the field of an IGGF of the second decomposition standard. The second phased pulse generator 17 pulses from the output 95 frequency pulses F2 5 and is phased by pulses CG2 from the output 8k of the second synchronizer 16. The second frequency divider 18 divides the frequency F2 by K times. The code K2 is entered into a parallel register 53 (input 65) of the second frequency divider 18 (Fig. 8) by the output from the output 96 of the decoder 25 of the control unit 21. In the absence of a pulse of the selected line at the reset input of counter 5 (input 83), this counter is held in the zero state.

The operation of the counter 5 is resolved upon receipt of a reset at its input 83

20 pulses of the selected line from the output of the second block 20 line selection (output 83). After the first pulse of frequency F2 arrives at the subtracting input of counter 5 (input 95) at the output 25 of transferring the counter, a CHI appears, which enters the pre-recording input of the same counter and overwrites counter 5 of the code "2 from the output of register 53." From this

The -3Q time instant counter 5 operates as a frequency divider with a division factor of r, from which output the clocking pulses of the frequency FT2 are removed (output 85).

The second selection block 20 receives a command B2, the code of which consists of two information parts. In the first part, the code of the selected row n2 is transmitted. The size of this part of the team B is 40t

is the maximum possible value of pg, i.e. Nz. In the second part

50

55

the B2t mandates occupying one bit are transmitted the code of the field Field Pr in the frame of the second standard. The command code B2 is written in-parallel register 35 (input 65) of the second row extracting unit 20 (Fig. 4) by the output from the output 97 of the decoder 25 of the recording signals of the control unit 21. During the flyback across the field, the PGI2 pulse rewrites the code n from the output of register 35 into a 36 line counter. After the counting input of the counter 36 (input 84) of the SGI2 pulses arrives at the counting input, the signal from the counter output output sets the first trigger 37 to state 1. The next pulse SGI2 returns trigger 37 to state 15

E. O. At the same time, at the output of the first rigger 37 a pulse of the extracted row „

The selection of the floor in the second block 20 of the row; the line is the same as in the first block 2 of the construction line. Moreover, the second 29 and third 30 riggers, shaper 31 pulse holders, inverter 32, switch 3, element And 3 of the first block 2 leveling lines correspond to second 8 and third 39 triggers, shaper 0 pulse delay, inverter 1, switch 42, element And 43 of the second block 20 line selection. The pulse of the selected row of the second stanlard decomposition is removed from the output 83 of the element And 43.

Video recording in the second mode of operation is as follows. After installing the controlled blocks in the required states in the computing device 23 of the control unit 21, the prohibition is removed from the second input 9 of the interrupt request. The first IGT pulse, appearing at the output 94 of the second synchronizer 16 after the removal of the prohibition and arriving at the input 94 of the control unit 21, indicates the beginning of the next field in the second decomposition standard. This pulse arrives at the input of the second interrupt request (the input of the computing device 23 and causes a transition to the service program of this request. According to this program, a command R is written to the memory unit 19, which switches the memory unit to the second decomposition standard. The command code is R2 It has the same components as the RM code and is also entered into the memory block 19. The difference is that the command code r3 switches the first memory switch 55 into the second state. After issuing the R2 command, it is prohibited to receive requests on the second input 94 of the computing device 23, the prohibition is removed from the first input 83 of the interrupt request of the computing device 23 and the computing device goes to the request for the first input 83. The first input 83 of the interrupt request is pulsed with the selected line (output 83). An interrupt request is generated in computed 1555918

ten

15

20

25

thirty

35

40

those are the same

18 on (in ne on sc

“And for the sake of ne

in p in in e p R

one

1 to

45

50

a 55

sixteen

five

0

five

0

five

0

unit 23 for the pulse decay of the selected line. The pulse of the selected line from the output 83 of the second block i of the 20 lines is also fed to the reset input of the second divider

18 frequencies, allowing his work, and to the fourth input of memory block 19 (input 83). Further, this pulse through the first switch 55 of the memory unit is fed to the input of the write-read control of the accumulator 60 (NF input)

„And sets the drive to record mode. In this case, the clocking pulses of the frequency GTG from the output 85 of the second frequency divider 18 arrive at the first input of the memory block 19 and then through the first 55 and second 56 switches to the summing input of the address counter 59 (input 87). The recording of video samples in the drive 60 is the same as in the first mode of operation. Moreover, in the accumulator 60, M2 k counts are stored.

After the recording of video samples is completed by the pulse drop of the selected line, the computing device 23 proceeds to the interrupt request service program at the first input 83. This prohibits subsequent requests from this input and the RJ command is entered into the parallel register 57 of the block

19pam ti. Code D3 switches the unit

19 of the memory for playback of the recorded video signal and consists, like the code R, of the parts r ,, - Гч. The code g determines the step size of the address d, which is calculated as follows:

(3) adder 5 & to mode

45

commutator code

56 at 50

55

SC The code r3 includes the first torus 55 in the third state, turns on the second commutator switch state.

Video playback in the second mode of operation is as follows. The pulses of the SGI, from the output 63 of the first synchronizer 11, go to the third input of the memory block 19 and then through the first 55 and second 56 switches to the reset input 88 of the counter 59 of the address. In this case, the counter 59 is set to the zero state. Pulses frequency Fg, raster elements of the first standard razloseg / 1

Neither of the switch output 76 of the 5 clock pulses arrive at the seventh input of memory block 19 (input 76) and then through the first 55 and second 5 & switches to the input 89 of the preliminary recording of the counter 59 of the address. Immediately after setting the address counter 59 to the zero state, from its output to the address input of the accumulator 60, the zero address arrives and a video signal stored at this address appears at the output 92 of the accumulator. At the same time, the address code from the output of the counter 59 goes to the second information input of the adder 58, the first information input of which is fed to the code of the address d from the output

78 reg. 57.

The output of the adder 59 is set to the code of the sum of the numbers at its inputs, i.e. code d. The first pulse of the frequency of the RE1, arriving at the input 89 of the preliminary recording of the counter 59 of the address, writes into the counter 59 a code of this amount, from the accumulator 60 the count stored at address d is read. After the second pulse of frequency Re, a count is read at address 2d, and so on. to address M, - d Thus, when reproducing a video signal in the second mode of operation, out of M2 k samples stored in drive 60, only M is used, samples taken in steps d. This is due to the limited resolution of the video monitoring unit 10 operating in the first decomposition standard. The formation of the oscillogram of the video source in the second mode of operation is the same as in the first mode.

The reproduction of the video signal in the second mode of operation is of an overview nature and makes it possible to evaluate the general form of the waveform for the case when M2 is larger than M ,. In the case when Ma is less than M, choosing the value of k can be obtained that the value of M2-k will be equal to or greater than M, and the waveform of the video signal will be reproduced with high accuracy in the second mode of operation.

In the second mode of operation, the recording of the video signal for its subsequent reproduction can be carried out either by a command from the keyboard 22 of the control unit 21, or in each frame (selected field). After first switching on the second mode of operation, calculate

1818

The control unit 23 of the control unit 21 executes the recording program by a command from the keyboard. To record the video signal in each frame (selected field), the recording feature in each frame is entered into the computing device 23 from the keyboard 22. In this case, after recording the video signal and switching to playback in computing device 23, the prohibition on the second input 9 t of the interrupt request is lifted, and when the next PGI pulse arrives at this input, the recording and playback process repeats. Recording a video signal using a command from the keyboard 22 allows one to estimate the long-term changes in the video signal, the recording in each frame (selected field) - short-term changes from frame to frame (from field to field).

In order to activate the third mode of operation of the device for playing the video signal from the keyboard 22, the number of this mode is entered into the computing device 23. In this case, the K command is sent to the first frequency divider 13, the R4 command is sent to the memory block 19, the 3th row elements counter is the T command, and the 3 elements The command code K, in this mode of operation, corresponds to the division ratio, defined as

K - K ° M

to MPG

W

With this K, the frequency FT (pulses at the output 7b of the switch 5 of the clock pulses used to form the mark signal in the first decomposition standard provides the following relation:

M,

M,

M.

(five)

L,

In the third mode of operation, the waveform of the video signal section is reproduced with maximum accuracy using M, consecutive samples, starting with some initial drive address Ah, which determines the position on the image line of the label in the first standard (value t () and its equivalent in the second decomposition standard ( magnitude gog).

The R command switches the memory block 19 to work in the third mode of operation. Code R contains the same parts.

nineteen

g, - Hz, as the code R ,. Code r {corresponds to the initial address of An. Code r2 includes adder 58 in SP mode. Code g includes the first switch 55 in the third state. The hch code includes the second switch 56 in the third state.

Immediately after switching on the third mode of operation, the code r, the command R4 contains the initial value A, for example the zero address of the accumulator 60. Moreover, the command t recorded in the counter of 3 line elements should also indicate the zero position of the image of the mark on the video control unit 10 screen. In the process of playing the video signal in the third mode of operation from the keyboard 22 of the control unit 21, the position of the mark on the line is changed by changing the value of An. In accordance with the change in An, the value of m is also changed, which is defined as

15

t

And, - AN M2 k

(6)

where r is the whole part.

Video playback in the third mode is as follows. The pulses of the SGI from the output 63 of the first synchronizer 11 arrive at the third input of the memory block 19 and then through the first 55 and second 56 switches to the input 88 of the preliminary recording of the counter 59 of the address. Consequently, the register 57 at the beginning of each line records the code An, which from output 78 through the adder 58 feeds the information input of the counter 59. From the output of the counter 59 of the address, the code AN goes to the address input of the storage device 60, the output of which is read to this address. The frequency pulses F3, from the output 76 of the switch 5, clock pulses arrive at the seventh input of the memory unit 19 and then through the first 55 and second 56 switches to the summing input 87 of the address counter 59. After the first pulse of frequency F51, the contents of counter 59 become equal to AC + 1, after the second pulse, An + 2 and t = d. During each line of the first standard, from the accumulator 60, readings are read from the address A + 1 to An + M ,. Oscillogram

1555918

20

The video signal is generated in the same way as in the first operation mode. When changing the AC to select the reproducible part of the second standard decomposition line, the computing device 23 programmatically ensures that

BUT,

+ M,

Vk

(7)

so that the reading of samples from accumulator 60 does not occur outside the recorded array.

Thus, a device for reproducing a video signal allows to reproduce video signals of various decomposition standards on the video monitor screen of a fixed standard block, since it provides for a change in the time scales of the signals by recording according to the parameters of the decomposition standard, and reproduction with the required fixed frequency.

Claims (1)

Invention Formula 0 five 0 0 five A device for reproducing a video signal, comprising an analog-to-digital converter whose input is a video signal input, a first line selection unit, a line element counter, a mark length counter, a clock switch, a trigger, serially connected display area selection unit, a code comparison unit, a mixer, video monitoring unit, serially connected first synchronizer, first phased pulse generator, first frequency divider, the first output of which is connected to the first information The clock input of the switch is clocked, pulsing, and to the counting input of the row element counter, the first and second outputs of the first synchronizer are connected respectively to the first and second inputs of the first row selection block, a switch that is by reproducing the video signal of television systems having different decomposition standards, a decomposition standard converter is introduced, the output of which is connected to the first input of the switch, the output of which is dinen with the second input of the mixer and 21t 5 the input of the first synchronizer, and the second input of the switch and the input of the decomposition standard converter are combined with the input of the analog-digital converter, the second synchronizer connected in series, the second phased pulse generator, the second frequency divider, the memory block, the second input of which is connected to the analog-digital output the converter, the first output of the memory block is connected to the second input of the code comparison block, and the second output is connected to the clocking input of the analog-digital converter, the second block of line selection and a control unit, wherein the first output of the second synchronizer is connected to the third input of the memory unit and the first input of the second line selection unit, the output of which is connected to the fourth input of the memory unit, the first input of the control unit and the reset input of the second frequency divider, and the second input of the second the synchronizer is connected to the second input of the second line selection unit and the second input of the control unit, the output of which is connected to the control inputs of the second frequency divider, the second line selection unit, the first allocation unit Display unit selection unit, first frequency divider, line element counter, memory unit, fifth FIG. 2 18 22 0 five 0 five 0 The output of which is connected to the first output of the first synchronizer, the sixth output to the output of the first line selection unit, the seventh input to the output of the clock switch, the second information input of which is connected to the second output of the first frequency divider, the reset input of which is combined with the preliminary recording input of the element counter line and connected to the first output of the first synchronizer, the second output of which is connected to the first input of the display area selection unit, the second input of which is combined with the reset input of the account The tag of the tag length is connected to the first output of the first synchronizer, the output of the clock switch is connected to the clock input of the tag length counter, the output of which is connected to the synchronization input of three, the input of installation 1 of which is connected to the output of the counter of line elements, the input of installation O to the output the first block of line selection, the D input of the trigger is connected to the logic level O, the output of the trigger is connected to the third input, the mixer and the control input of the clock switch, and the input of the second synchronizer bedinen with the input of the analog-to-digital converter. RigZ 65 97 94 in 65 „, 88 04 63 69 of FIG. five 7 ri g A $ 5, 68 & I 59 91 60 492 U f field eight U ( ffb ttn 57 7B 86 SB / % 55 83 85 M 76, 63 67 f Fig 9  02 Zsrcrsre Fig.M Ml Sh Phi // YAU I m j. N9 / g //