KR0144976B1 - Video signal recording medium method and apparatus of fast reproduction of video signal - Google Patents

Abstract

The present invention relates to a recording format and apparatus for a high speed reproduction of a video signal and a method thereof, wherein the video signal corresponds to a predetermined multiple of a control signal of a predetermined frequency in a control track of a recording medium recorded on a data track in a segmented manner. A recording format in which a double speed control signal for double speed reproduction with a recording medium is recorded, and a device for reproducing a recording medium having such a recording format includes a waveform reproducing signal reproduced by a reproduction amplifier and a reproduction amplifier for reproducing a signal recorded on a control track. A data detector to count the waveform-shaped signal in the data detector, a counter to count the period of the plurality of tracks M constituting one field, and store the acceleration time and the number of the speed control signals according to the predetermined speed (N) reproduction mode. Memory field and one field cycle operation depending on the data stored in the memory and the counter result Is a cap that controls the running of a tape by inputting a control signal of a microcomputer or a microcom to output a control signal so that the (N-1) * M track can be driven at high speed and the normal playback of the M track can be repeated during another field period. Including a capstan speed controller for driving a stator motor, the tape speed is changed to correspond to the set speed, thereby reproducing only a predetermined interval of screen, thereby providing a high-quality clear image.

Description

Video signal recording medium, high speed playback device of video signal and method thereof

1 is a head trajectory diagram of a tape with a guard band in a conventional high speed playback.

2 is a head trajectory diagram of a tape recorded with a double azimuth in the conventional high speed reproduction.

FIG. 3A is a block diagram of a double azimuth system for reproducing a signal carried on the tape shown in FIG.

3b to 3d are operational waveform diagrams for the double azimuth system shown in FIG. 3a.

4 is a recording format and head trajectory for high speed reproduction according to the present invention.

5 is a block diagram according to an embodiment of a high-speed playback apparatus of a video signal according to the present invention.

6A to 6C are operational waveform diagrams of the high speed reproducing apparatus shown in FIG.

7 is a capstan speed change characteristic diagram according to high speed regeneration controlled by the capstan speed controller shown in FIG.

8 is another capstan speed change characteristic diagram according to high speed regeneration controlled by the capstan speed controller shown in FIG.

FIG. 9 is a flowchart for explaining a method for high speed reproduction of a video signal performed in the microcomputer shown in FIG.

FIG. 10 is a subroutine in the normal playback mode shown in FIG.

FIG. 11 is a subroutine in the fast playback mode shown in FIG.

* Explanation of symbols for the main parts of the drawings

100: control head 101: key input

110: regenerative amplifier 120: waveform equalizer

130: data detector 140: counter

141: memory 150: microcomputer

160: Capstan speed controller

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a recording format and apparatus for a high speed reproduction of a video signal in a video recording and reproducing apparatus, and more particularly, to recording a control speed of a predetermined frequency on a control track of a recording medium and counting the control signal. The present invention relates to a video signal recording medium for reproducing a clear picture quality by reproducing only screens of a predetermined interval by varying a tape speed corresponding to a double speed set to a high speed, and a high speed reproducing apparatus of a video signal, and a method thereof.

In a video recording and reproducing apparatus such as a conventional video cassette recorder (VCR), when the image is reproduced while driving the tape at high speed, the data track recorded on the tape and the scanning track of the VCR head do not coincide with each other. Can not play.

For example, as shown in FIG. 1, a guard band recording method is employed to remove crosstalk between adjacent tracks, but a noise bar caused by a guard band is used. (bar) or the like also causes a problem that the image quality is also lowered.

In order to solve this problem, as shown in FIG. 2, the double azimuth recording method has been developed and the image quality has been improved to some extent. However, the head having the positive azimuth angle during double speed playback is recorded as an inverse azimuth angle by this azimuth. Because a signal cannot be read, even if a head traces several tracks, a signal recorded at an azimuth angle opposite to the head cannot be read, and therefore only half of the trace can be reproduced. There was a problem that noise and circuitry became complicated.

Here, a system for reproducing a tape recorded with the double azimuth shown in FIG. 2 is as shown in FIG. 3A.

First, when recording a video signal (field signal) on a track of a tape, the method of recording at a ratio of one field per track is called a non-division recording or non-segment type. The method of recording by dividing into a plurality of tracks is called a division recording or segment type.

Since the tape recorded with the double azimuth shown in FIG. 2 is recorded in a segmented manner in which two tracks are composed of one field, the tape is reproduced using four heads as shown in FIG.

Two heads (HA, HB) play the radix (excellent) field, two heads (HA ', HB') play the excellent (radix) field, and HA, HA 'convert the static azimuth track (A-1) to HB. , HB 'regenerates the secondary azimuth track (B-1).

The reproduction signals outputted through the four heads HA, HB, HA ', and HB' are amplified by the first to fourth amplifiers 11-14, and the first control switch 31 is the first comparator 21. The output of the first amplifier 11 or the second amplifier 12 is selected in accordance with the output signal of the second amplifier, and the second control switch 32 is the third amplifier 13 according to the output signal of the second comparator 22. Or select the output of the fourth amplifier 14.

Here, the output signal waveform of the first amplifier 11 is as shown in Figure 3b, the output signal waveform of the second amplifier 12 is as shown in Figure 3c of the first comparator 21 When the output is as shown in FIG. 3c, the output of the first comparator 21 is as shown in FIG. 3c.

In the third control switch 40, the output of the first or second control switches 31 and 32 is selected according to the head switching signal of 60 Hz.

The regeneration amplifier 50 amplifies the signal switched by the third control switch 40, and the demodulator 60 demodulates the output of the regeneration amplifier 50 to output the final regeneration signal.

Therefore, the above-mentioned double azimuth system employs a double azimuth head (4 heads) to increase the pick-up amount, but switching noise due to head switching appears on the screen as flicker or bleeding, resulting in deterioration in image quality. The circuit is complicated by the switching switches for switching the output of each head amplifier and each amplifier according to four heads.

In order to overcome the above-mentioned problems, it is an object of the present invention to provide a video signal recording medium for high speed reproduction in which a double speed control signal of a predetermined frequency is recorded on a control track on a recording medium in an image recording and reproducing apparatus.

Another object of the present invention is to reproduce only screens of a predetermined interval by varying the tape speed corresponding to the speed set as a result of counting a speed control signal loaded on a recording medium in which a speed control signal of a predetermined frequency is recorded on a control track. The present invention provides an apparatus and method for high-speed reproduction of a video signal that can be implemented by a high-quality image and a hardware simple circuit.

In order to achieve the above object, an image signal recording medium according to the present invention comprises an image track having a data track in which one field is composed of two tracks and data is recorded in a double azimuth method, and a control track in which control signals are recorded. In a signal recording medium, a first speed control signal for reproducing data at a normal speed for one field period is recorded on the control track, and for reproducing data at a predetermined speed of the normal reproducing speed for another field period. A second double speed control signal is recorded, and the first and second double speed control signals are alternately recorded.

In addition, the video signal fast playback apparatus according to the present invention is recorded on a data track in a segment manner in which a plurality of tracks are composed of one field, and the control track has a double speed playback having a frequency corresponding to a predetermined multiple of a control signal of a predetermined frequency. An apparatus for reproducing a recording medium in which a double speed control signal for recording is recorded; Reproducing means for reproducing a signal recorded on the control track; Waveform shaping means for waveform shaping the signal reproduced by the reproducing means; Detection means for counting the waveform-formed signal in the waveform shaping means and detecting a period of a plurality of tracks constituting a field; Memory means for storing an acceleration time according to a predetermined speed (N) reproduction mode and the number of the speed control signals; According to the data stored in the memory means and the count means corresponding to the predetermined speed regeneration mode, (N-1) * M tracks are driven at high speed during one field period, and M track is normal during the period of another field. Control means for outputting a control signal so that reproduction can be repeated; And a motor driving means for driving a capstan motor for controlling the running of the tape by inputting a control signal of the control means.

The video signal high speed playback method according to the present invention is recorded in a data track in a segment method comprising a plurality of tracks in one field, and the control track has a double speed for double speed reproduction at a frequency corresponding to a predetermined multiple of a control signal of a predetermined frequency. A reproduction method for reproducing a recording medium on which control signals have been recorded:

Reproducing the double speed control signal recorded in the control track; Counting the double speed control signal to count a period of a plurality of tracks corresponding to one field; According to the count result corresponding to the predetermined speed (N) reproduction mode, high speed driving of (N-1) * M tracks during one field period and normal playback of M tracks can be repeated during another field period. It is characterized by controlling the capstan motor.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of a recording format, an apparatus, and a method for high speed reproduction of a video signal according to the present invention will be described with reference to the accompanying drawings.

4 shows a recording format for high-speed reproduction of a video signal according to the present invention and a head trajectory according thereto.

4 shows a trace relationship of the head during high-speed reproduction, which is recorded as a signal at a frequency n times the one track time (1/60, 1/120) at 1x speed on the control track.

Therefore, in the present invention, since one field is recorded in a two-track segment method and a double azimuth, noise and pick-up amount are reduced by noise bars generated during high-speed reproduction of a recording medium having a guard band shown in FIG. 2 tracks are normally played during high-speed playback, and multiple [(N-1) * 2] tracks corresponding to the double speed mode (N) are skipped during the time when 2 tracks are played, and 2 tracks are normally played again. By repeating the method, the noise caused by the head switching does not occur as in the double edge mus system shown in FIGS. 2 and 3, and double speed reproduction is possible with the two heads, thereby eliminating the problem of complicated circuit like the double edge mus system. .

Here, the frequency of the double speed control signal on the control track is: 1) the size of the head gap, 2) the tape speed for reproduction up to the maximum speed, 3) the shortest recording wavelength (about 2.5-3 times the size of the gap). , ④ λmin = (V _TAPE ) Select N times frequency of 120Hz that satisfies four conditions of _max / f _max .

For example, the size of the gap = 0.5 μm, (V _TAPE ) _max = V _TAPE x M double speed (where V _TAPE = 14.345 mm / sec in the case of 8 mm tape), and M = 10.

(V _TAPE ) _max = 143.45 mm / sec and λmin = 2.5 × gap size = 2.5 μm.

therefore,

to be.

At 1800 rpm and 60 Hz, N = 1900, and at a drum speed of 3600 rpm, a multiple of 120 Hz closest to 114 KHz would be N = 950. In other words, the maximum value of the recording frequency is 120 Hz x 950 = 114 KHz.

Next, an embodiment of a high speed reproducing apparatus for reproducing a recording medium having a recording format shown in FIG. 4 will be described.

5 is a block diagram according to an embodiment of a fast playback apparatus of a video signal according to the present invention.

The apparatus according to the present invention includes a control head 100, a regenerative amplifier 110 connected to an output terminal of the control head 100, a waveform equalizer 120 connected to an output terminal of the regenerative amplifier 110, a waveform, and the like. The data detector 130 connected to the output terminal of the firearm 120, the counter 140 connected to the output terminal of the data detector 130, the microcomputer connected to the output terminal of the counter 140 and the output terminal of the key input unit 101. (150), a memory 141 whose data output terminal is connected to the microcomputer 150, an input terminal of which is connected to a control signal output terminal of the microcomputer 150, and an output terminal of the capstan speed controller connected to a capstan motor (M). It consists of 160.

The operation of FIG. 5 will be described with reference to FIGS. 6A to 8.

According to FIG. 5, a tape (TAPE) in which a signal of frequency n times one track period (1/60, 1/120) is recorded on the control track at 1x speed (normal playback) is inserted into the control head 100. By reproducing the amplified signal through the reproducing amplifier 110 and outputting the signal as shown in FIG. 6A.

The waveform equalizer 120 is again inputted to the data detector 130 after waveform equalization as shown in FIG. 6B.

When the data detector 130 reproduces the waveform as shown in FIG. 6C as a clock signal having a frequency n times the control signal (60 Hz or 120 Hz) and inputs it to the counter 140, the counter 140 returns 2. The number of clocks during the time period corresponding to the track period is counted.

On the other hand, the count value of the counter 140 is input to the microcomputer 150 to control the capstan speed, and in the microcomputer 150 when the speed setting mode is set from the key input unit 101, The capstan speed is adjusted by a program with the motor speed control characteristic as shown in FIGS. 7 and 8 according to the performance and characteristics.

Here, the memory 141 such as the ROM table stores the acceleration time and the number (count value) of the speed control signals corresponding to the speed.

That is, when a key for reproducing the speed at predetermined times (N) is input from the key inputter 101, the microcomputer 150 counts the count value output from the counter 140 and the acceleration time and clock for the speed from the ROM table 141. The speed of the capstan motor M is controlled by reading the number and outputting information such as the maximum speed, the time to the maximum speed, and the count value to the capstan speed controller 160. The capstan motor from the capstan speed controller (16) which inputs a control signal for controlling the capstan motor (M) at (N-1) * 2 times during 2 track times and 1 times during 2 track times. (M) is controlled as shown in FIG. 7 and FIG.

7 and 8 show the change in the capstan speed according to the double speed regeneration, and the slope of the graph shows the maximum acceleration speed of the capstan motor (M), and the stable 1x speed at least within this time of 2 tracks. You should be able to get the speed, and depending on the performance and characteristics of the system, the maximum acceleration, or slope, may be somewhat different, and the slope defines the maximum speed, and for 2 track times (N-1) * 2 times, N times is performed by repeating 1x speed for 2 track times.

That is, in the capstan speed controller 160, the higher the speed, the shorter the time until the maximum speed. The capstan motor M is driven at the highest speed in FIG.

In summary, during the high speed playback mode, the running speed of the tape (or the rotational speed of the capstan motor) is repeated as normal speed → high speed → normal speed → high speed. In this way, even if the running speed of the tape is changed from the high speed playback speed to the normal playback speed, the scanning path of the head and the track of the tape coincide with each other.

Therefore, when the running speed of the tape is the normal playback speed, the data recorded on the tape is read out, recorded in the frame memory (not shown), and the contents of the frame memory are displayed. At this time, the running speed of the tape (or the rotational speed of the motor) changes from the normal playback speed to the high speed playback speed, so the screen of the data stored in the frame memory is maintained until the next normal speed is reached.

When the running speed of the tape reaches the next normal playback speed, new data is read from the tape and stored in the frame memory. By repeating the above-described playback operation in the high-speed playback process, a stable and clear playback screen is read to form a new screen.

FIG. 9 is a flowchart for explaining a method for high speed reproduction of a video signal performed by the microcomputer shown in FIG.

Referring to FIG. 9, the speed input mode key is input through the key input unit 101 (step S10).

When the double speed mode (N) is set to 1x speed, the normal play mode is executed (steps S20 and S30). If the double speed mode is set to the maximum speed or less, the high speed play mode is performed. It is fed back (step S40, S50).

FIG. 10 is a subroutine in the normal playback mode shown in FIG.

Referring to FIG. 10, the counter 140 is initialized every 1/120 or 1/60 (step S31), the speed control signal loaded on the control track is counted from the counter 140, and a count value is input (step S32). When the speed control signal is 114KHz, the capstan speed controller 160 maintains the speed of the capstan motor M (steps S33 and S34). Assume that the double speed control signal on the control track has a frequency of 114 KHz.

If the speed control signal is greater than 114KHz, the capstan speed controller 160 decelerates the speed of the capstan motor (M). If the speed control signal is less than 114KHz, the speed of the capstan motor (M) is increased (S35-S37). step).

FIG. 11 is a subroutine in the fast playback mode shown in FIG.

According to FIG. 11, the acceleration time and the number of clocks corresponding to the double speed are received from the ROM table 141, and the capstan speed controller 160 controls the speed of the capstan motor M according to the N speed (S51-). Step S52).

If the play key is input and the play key is input, the normal play mode is performed. If the play key is not input, a count value is input from the counter 140 (steps S53 to S55).

If the count value is a value suitable for double speed, that is, a 114KHz double speed control signal, the normal playback mode is performed, and normal playback is performed for a time corresponding to two tracks, otherwise the feedback is returned to step S55 in which the count value is input (S56-). Step S58).

As described above, the recording format of the video signal recording medium according to the present invention, the video signal high speed reproducing apparatus and the method record the control signal of the predetermined frequency on the control track of the recording medium and then count the control signal. By varying the tape speed so as to correspond to the double speed set to, only a screen having a predetermined interval is reproduced, thereby providing a clear image of high quality.

In addition, since the present invention can reproduce the recording medium recorded with the double azimuth using two heads, it is possible to simplify the hardware.

Claims (3)

In a video signal recording medium having a track consisting of two tracks in which a field is composed of two tracks and a control track in which a control signal is recorded, the control track has a normal speed for one field period. A first double speed control signal for reproducing data is recorded, and a second double speed control signal for reproducing data at a predetermined speed of the normal reproduction speed is recorded for another field period, and the first and second double speed control signals are recorded. The video signal recording medium, characterized in that alternately recorded. A recording medium in which a plurality of tracks are recorded in a data track in a segmented manner, and a control medium for recording a double speed control signal for double speed reproduction having a frequency corresponding to a predetermined multiple of a control signal of a predetermined frequency is reproduced. An apparatus comprising: reproducing means for reproducing a signal recorded in the control track; Detection means for counting the waveform-formed signal in the waveform-shaping means and detecting periods of a plurality of tracks constituting one field; Memory means for storing an acceleration time according to a predetermined speed (N) reproduction mode and the number of the speed control signals; According to the data stored in the memory means and the counting means corresponding to the predetermined double speed reproduction mode, (N-1) * M tracks are driven at high speed during one field period, and M tracks are normally reproduced during the period of another field. Control means for outputting a control signal so that this can be repeated. And a motor driving means for driving a capstan motor for controlling the running of the tape by inputting a control signal of the control means. Reproducing a recording medium in which a plurality of tracks are recorded in a data track in a segment method consisting of one field, and in which a speed control signal for double speed reproduction is recorded at a frequency corresponding to a predetermined multiple of a control signal of a predetermined frequency. A method comprising: reproducing the double speed control signal recorded in the control track; Counting the double speed control signal to count a period of a plurality of tracks corresponding to one field; Corresponding to the predetermined playback speed (N) mode, high speed driving of (N-1) * M tracks during one field period and normal playback of M tracks during another field period may be repeated according to the count result. A video signal and a high speed playback method characterized by controlling a capstan motor.