KR100225414B1 - Apparatus for recording and playing video signal on stsandand vhs tape in high quality - Google Patents

Abstract

The present invention divides an input video signal into one field for every two fields, expands each signal, converts the signal into a low frequency band signal, and records the signal on two channels of a standard VHS video tape without loss of the frequency band. The present invention relates to a high-definition recording and reproducing apparatus for reproducing a high-definition video signal on an existing standard VHS videotape by recording a video signal in high quality and restoring the two-channel signals recorded as a normal video signal. Among these, a high quality recording apparatus includes: a signal selector 10a and a video signal decoder 20a for separately outputting an input video signal into luminance and color difference signals; Analog / digital converters 41a and 42a for digitally converting and outputting the color difference signal separated from the luminance signal; A demultiplexer 50a which alternately distributes and outputs luminance data; Memory (6) for storing both luminance data distributed

1a, 62a); A memory 63a for storing the converted color difference data; First and second multiplexers 71a and 72a for sequentially selecting and storing the stored luminance and color difference data at a predetermined time ratio; A field memory (80a) for storing the output data of the second multiplexer (72a) for a predetermined time; A digital / analog converter 9 converting the output data of the first multiplexer 71a and the output data of the field memory 80a into analog signals and inputting them to the Y / C signal processing units 210 and 220, respectively.

1a, 92a); It can be used to record high-definition video signals with a resolution of about 400 copies and a wide color band of 1.2 MHz, while using standard VHS video tapes and existing luminance and color signal processing circuits. It is a breakthrough and very useful invention.

Description

High definition recording and playback equipment using standard VHS videotape

The present invention relates to a high-definition recording and reproducing apparatus using a standard VHS video tape, and a head drum used therein. More specifically, the present invention relates to two fields by alternately distributing an input video signal for each field line by line. Each signal is extended on the time axis, converted to a low frequency signal, and recorded on two channels of standard VHS videotape to overcome the bandwidth limitations of the existing standard VHS videotape and videohead. High-definition recording without loss of the frequency band of the video signal, and by reproducing the two-channel signal recorded in this way to the normal video signal by reconstructing the signal of the two separate fields, the high-quality video on the existing standard VHS video tape A high quality recording and playback device capable of recording and playing back signals and the head drum used therein will be.

In case of recording the video signal received by using normal video tape, because of the characteristics of the head and the video tape, it is impossible to record the entire NTSC video signal band of about 4.2MHz, and only about 3MHz band is recorded. High-frequency signals with signal changes will not record and play back. Therefore, the signal reproduced after recording has a lowered sharpness than the original video signal, thereby degrading the image quality.

In order to solve the above problems, many researches have been conducted and are being conducted. Yoshito Nagaoka et al. In IEEE 1989, home appliances section 35, No. 3, `` 2 using orthogonally arranged heads '' Channel Record VRC ”was published. As shown in Fig. 1, the time-division selection of a 1H signal (a scanning line of 63.5 μs) is performed as a color burst signal, two color difference signals compressed at a time of 2.7 times, and a luminance signal extended by 1.5 times as shown in FIG. After converting into 2H signal and recording on one channel of video tape, the next 1H signal is converted into all 2H signal in the same way and recorded on the next channel. In order to perform frequency modulation recording, a sine wave of 4.4 MHz for the sync tip and 6.5 MHz for the white peak level was used.

In addition, the color burst signal recorded every 2H is extracted and used as an input signal of a phase lock loop (PLL) to obtain an accurate time reference signal to prevent a change in the time axis during processing of a reproduction signal. The time-base distortion of the reproduced signal is prevented from occurring based on the locked output signal as a time reference.

In addition to the above methods, a method of enabling high quality recording and playback by dividing and recording received video signals into two channel signals has been proposed. One of them is Mitsuo et al. Section 3, Volume 3, `` W-VHS V-seal of a New System for Multi-Purpose Recording Including HDTV Method ''. In the separate recording method, high-quality recording / reproduction of color signal band of 1 MHz or more and luminance signal band of 6.5 MHz or more can be performed according to each recording mode.

However, in the case of two-channel recording V-Cell such as Yoshitomi Nagaoka, although the video signal can be recorded in high quality, as shown in FIG. 1, the 1H video signal is extended to a 2H time zone to display a color burst signal, By time-dividing and selecting two color difference signals that are 2.7 times compressed and luminance signals that are 1.5 times extended, the time-base allocation area for color signals and luminance signals is reduced, and both visually less sensitive color difference signals are included in the time division selection. As a result, the luminance signal that greatly influences the image quality is not sufficiently extended, and the frequency band is not greatly reduced, so that the luminance signal of the high range is not recorded but lost. In the above method, in order to compensate for this disadvantage, the frequency modulated carrier to be recorded has to use a new high frequency without using the frequency modulated carrier used in the VRC, and thus, a new luminance and color signal processing circuit must be designed. There is a problem in that a video tape of a medium capable of recording a higher band signal has to be manufactured.

In addition, as a reference input signal of the PLL for obtaining a constant time reference signal of the reproduction signal, a color burst signal recorded together with a time-division synthesized luminance and color signal of 2H is used. Not only is it disadvantageous to generate an accurate time reference signal that is unbiased, but if a signal drops out during playback, the reference signal is not input to the PLL for 4H, so that the phase signal There is a problem that the time-base distortion of the reproduction signal occurs due to the frequency change.

And V-R of W-VHS such as Mitsuo is a high-definition signal such as high-definition broadcasting signal (HDTV) for accommodating a signal whose luminance signal band is about five times the luminance signal band of the current standard VHS tape. In order to accommodate such a method, it is necessary to develop a completely new recording / playback device rather than a conventional recording / playback device that is widely used and used as a recording medium. Expensive tapes, such as metal tapes of 14.4μm in thickness, must be used, and recording heads must be used with new heads with narrow gaps made of thin films. Problem of having to input high quality broadcasting signal source that is different from current NTSC color TV broadcasting signal. This will be in.

Accordingly, the present invention has been made to solve the above problems, and a high-definition recording and reproducing apparatus for recording and playing back a video signal that is currently being broadcast using high-definition standard VHS videotape in high quality without band loss. Another object of the present invention is to provide a high quality recording and reproducing apparatus using an accurate time signal to obtain a playback signal without signal distortion due to time axis shift after recording. Another object is to provide a high quality recording apparatus having a recording ratio of luminance signal and color signal which maintains the highest image quality under the limitation of the recording band of standard VHS video tape.

1 shows a time-division mixed waveform of a color difference signal and a luminance signal according to a conventional method.

2 is a block diagram of a preferred embodiment of a high quality recording apparatus according to the present invention.

FIG. 3 schematically shows a luminance signal and a color difference signal separately output by the video signal decoder of FIG.

4 shows a process in which digital data having luminance and color difference information is separated in FIG.

5 shows waveforms synthesized at a time ratio of 4: 1 after digital data having luminance and chrominance information are separated.

FIG. 6 shows the signal configuration when the input selected video signal is recorded on the time axis.

7 is a waveform diagram showing the ratio of the luminance signal and the color difference signal.

8 is a diagram illustrating a form in which a video signal is separated and recorded on a tape by a high definition recording apparatus according to the present invention.

9 is a block diagram showing the configuration of a preferred embodiment of a high quality playback apparatus according to the present invention.

FIG. 10 is a plan view of a head drum on which a head used in the high quality recording and reproducing apparatus of FIGS. 3 and 9 is mounted.

FIG. 11 shows a schematic signal processing in comparison with the prior art to show the effect of constant reference clock for signal processing.

* Explanation of symbols for main parts of the drawings

1c: main head 2c: subhead

1b, 3b: frequency detector 2b, 4b: reference clock generator

10a: Signal selector 10c: Head drum

11b, 12b, 41a, 42a: Analog-to-digital converter 20a: Video signal decoder

20b, 80a: Field memory 30a: Switch

31b, 32b, 50a: de-multiplexer

41b, 43b: luminance data memory

42b, 44b: Color difference data memory

50b, 71a, 72a: multiplexer

60b: color signal encoder 61a, 62a, 63a: memory

71b, 72b, 91a, 92a: Digital-to-Analog Converter 80b: Signal Synthesizer

100a, 100b: control unit 110a: synchronous separator

111a: sine wave generator 210: main Y / C signal processing unit

211 and 221: luminance signal processor 212 and 222: color signal processor

220: sub Y / C signal processing unit 231, 232: switch

241, 242: selection switch

In order to achieve the above object, a high-definition recording apparatus using a standard VHS video tape according to the present invention includes signal separation means for separating a received video signal into one luminance signal and a plurality of color signals, and alternately the plurality of color signals. A signal compressing means for selecting and compressing the signal, the signal extending means for dividing the luminance signal sequentially according to horizontal synchronization and extending the first and second luminance signals to the first and second luminance signals, respectively, the expanded first luminance signal and the compressed color signal. First converting means for time-division selecting and converting to a single signal, second converting means for time-dividing and converting the expanded second luminance signal and the compressed next color signal into a single signal, and a conversion signal of the second converting means Delay means for delaying the predetermined time output, comprising a high-definition playback device using a standard VHS video tape according to the present invention, Delay means for delaying all channel signals of the signal for a predetermined time, first separation means for separating the luminance signal and the color signal from the later channel signal of the two channel signals, second separation means for separating the luminance signal and the color signal from the delayed signal, and the separation A luminance signal restoring means for compressing the two luminance signals and then alternately selecting the two luminance signals and outputting them as a single signal; a color signal restoring means for repeatedly outputting the separated two color signals once, and outputting the luminance signal from the luminance signal restoring means; And a video signal converting means for converting a plurality of output color signals of the color signal restoring means into a composite video signal. The recording apparatus according to the present invention is characterized by detecting a synchronization signal of the video signal. And a detection means, and reference signal generating means for generating and outputting a constant frequency signal interlocked with the detected synchronization signal. The reproducing apparatus according to the present invention is characterized by detecting means for detecting a constant frequency signal from a two-channel signal to be reproduced, and the signal processing speeds of the delay means, separating means, and restoring means of the reproducing apparatus based on the detected signal. And a control means for adjusting, each having a different feature, and the recording apparatus according to the present invention has a further feature in that the time division ratio between the extended luminance signal and the compressed one color signal is 4: 1. Is there.

In the high-definition recording apparatus using the standard VHS video tape according to the present invention configured as described above, first, the signal separation means separates the input video signal into a luminance signal and a plurality of color signals (or color difference signals). The signals are alternately outputted for each horizontal synchronous by the signal extension means, and the signals outputted for the bisection are respectively extended. The separated color signals are alternately selected by the signal compression means in synchronization with the horizontal synchronization signal, and the selected color signals are compressed. The extended luminance signal and the compressed color signal are time-division selected by the first and second converting means and synthesized into a single signal. One of a plurality of color signals in a video signal of a preceding field and a luminance signal It is selected and output as a single signal by the first converting means, and one of a plurality of color signals and a luminance signal in a subsequent video signal of one field are selected and converted into a single signal by the second converting means. In this case, the color signal converted into a single signal by the second conversion means is different from the color signal converted by the first conversion means because a plurality of color signals are alternately selected and output by the signal compression means. It becomes a color signal having. One of the signals converted into a single signal is signal-modulated according to the luminance signal processing and recorded on a standard VHS video tape through the main head, and the other signal is delayed by the delay means by a predetermined delay from the main head. After the subhead mounted at an angle is delayed by a predetermined time in contact with the video tape, the subhead is recorded on the video tape through the subhead processing, thereby converting the video signals of two adjacent fields into low-frequency two signals. They are recorded on two channels of each video track.

Apart from the above process, the reference signal generating means generates and outputs a signal of a constant frequency interlocked with a synchronization signal of a received video signal, and the constant frequency signal generated in this way is modulated by a conventional luminance signal processing circuit. The constant frequency is selected so as to be properly spaced apart in the frequency band so as to reduce interference of the frequency band with the signal converted and modulated by the luminance signal processing circuit.

The constant frequency signal recorded in all areas of the two channels is used as a reference signal for adjusting the speed of restoring the reproduced signal to the original signal in order to prevent a change in the time axis of the signal during reproduction.

On the other hand, in the high definition playback apparatus using the standard VHS videotape according to the present invention configured as described above, the reverse process performed by the recording apparatus is performed, in which case the time delayed at the time of the recording of the read-out read signal is performed. As long as the time is delayed, the delayed signal is restored to the original signal of the luminance signal and the color signal at the same time as the signal to be reproduced and restored, and interleaved with each other to restore the complete video signal.

Hereinafter, the configuration and operation of a preferred embodiment of a high definition recording and reproducing apparatus using standard VHS videotape according to the present invention will be described in detail.

2 is a block diagram of a preferred embodiment of a high-definition recording apparatus using a standard VHS video tape according to the present invention, comprising: a signal selector 10a for selecting one of a plurality of input video signals and separately outputting the luminance and color signals; A video signal decoder 20a for separating only the luminance signal separated from the signal selector 10a and the color signal among the color signals into two color difference signals; A switching switch (30a) for alternately selecting and outputting the two color difference signals according to a control signal (C0); Analog / digital converters 41a and 42a for converting the analog luminance signal output from the video signal decoder 20a and the analog color difference signal alternately selected and outputted by the switching switch 30a into digital data, respectively; A demultiplexer (50a) for alternately distributing and outputting the output data of the analog / digital converter (41a) for converting luminance signals into digital data according to the control signal (C0); Memory (61a, 62a) for storing both output data of the demultiplexer (50a); A memory 63a for storing output data of the analog / digital converter 42a for converting color difference signals into digital data; A first multiplexer 71a which sequentially selects data read out from the memory 61a in which the luminance data is stored and the memory 63a in which the chrominance data is stored at a predetermined time ratio according to a control signal CTL1; The data read out from the memory 62a in which the luminance data is stored and the memory 63a in which the chrominance data are stored are respectively selected at a predetermined time ratio according to the control signal CTL2, and are sequentially output. The memory 63a in which the chrominance data is stored is output. A second multiplexer 72a having a selective output point of < RTI ID = 0.0 >) < / RTI > in complementary relationship with the first multiplexer 71a; Output data of the second multiplexer 72a and the field memory 80a; The first multiplexer 7

Digital / analog converters 91a and 9 for converting the output data of 1a and the data read from the field memory 80a into analog signals and inputting them to the Y / C signal processing units 210 and 220, respectively.

2a); A control unit (100a) for outputting control signals (CTL0, CTL1, CTL2) in accordance with the input synchronization signal and adjusting the data storage time of the field memory (80a); A sync separator (110a) for extracting a horizontal sync signal from the luminance signal separated by the signal selector (10a); A sinusoidal wave generator 111a generating a sinusoidal wave signal 32.5 times the horizontal synchronization signal frequency; And selection switches 241 and 242 for selectively outputting one of the processed signal of the color signal processor 212 and 222 and the square wave signal by the controller 100a. As shown in the drawing, the main head 1c and the subhead 2c mounted on the head drum 10c at an angle of 120 ° are recorded adjacent to the standard VHS videotape.

In the high-definition recording apparatus according to the present invention configured as described above, one of a plurality of video signals is first selected by the signal selector 10a to be separated into a luminance signal and a color signal, and the separated luminance signal is the video signal decoder 20a. The signal is passed through as it is, and the color signal is decomposed into two color difference signals RY and BY and output. The two color difference signals decomposed are converted into the switch (3).

0a) is selected one by one, alternately selection is made by the control signal (CTL0) of the control unit (100a) output in conjunction with the horizontal synchronization signal of the selected video signal. That is, the luminance signal and the color difference signal among the color difference signals decomposed by the video signal decoder 20a as shown in FIG. 3 are alternately output by the switching switch 30a as shown in FIG. 4a. The color difference signal, which is alternately selected and output as a single signal, is sampled about 228 times according to an fsc (= 3.58 MHz) clock by the analog / digital converter 42a and stored in the memory 63a at the same rate. . Meanwhile, the selected luminance signal is also sampled by the analog / digital converter 41a approximately 910 times according to the 4fsc (= 14.32 MHz) clock and stored in the memories 61a and 62a at such a rate. The selection of the memory to be stored is alternately selected by the control signal CTL0 linked to the horizontal synchronization signal of the control unit 100a so that every other field is stored in the same memory. Accordingly, the data stored in the memories 61a and 62a become signals as shown in FIG. 4B, respectively. While the luminance data and the chrominance data are stored as described above, the controller 100a reads from the memories 61a, 62a, and 63a to time-division synthesize the luminance data and the chrominance data. same.

First, the control unit 100a applies a control signal CTL1 to the first multiplexer 71a to input an input terminal to a clock (520 X 15.748 kHz = 8.189 MHz) of 520f _h in the memory 63a in which the color difference data is stored. The control signal CTL1 is inverted again after selecting and outputting data to be read. The data read by the 520f _h clock is selected as an input from the memory 61a in which the luminance data is stored. The luminance data and the color difference data read out from the memories 61a and 63a by the clock frequency as described above are increased by about 1.749 times (14.32 MHz / 8.189 MHz = 1.749) and 43.7% (3.58 MHz / 8.189 MHz = 0.437), respectively. It is compressed (2.28 times compressed) to obtain a signal as shown in FIG. 4C. Color difference signal data and luminance signal data are selected by the controller 100a at a predetermined time ratio to output the data of the signal as shown in FIG. 5a as the data having the signal value as shown in FIG. 4c, and the data is converted into the digital to analog converter. By 91a, an analog signal obtained by time division combining the luminance signal and the color difference signal as shown in FIG. 5A is obtained. The ratio between the intervals is selected so that the 188 sampling data valid among the 228 sampled color difference data is selected, and the 752 sampling data valid among the 910 sampled luminance data are selected so that the ratio becomes 1: 4.

: 175H에 해당)이므로 상기 필드 메모리(80a)에 저장된 데이터는 기록되기 시작한 시점으로부터 정확히 11.1ms후에 기록시와 동일 속도로 독출되어 상기 디지털/아날로그 변환기(92a)에 의해 아날로그 신호로 변환되어 제5b도와 같이 휘도신호와 색차신호가 시분할 조합된 신호가 된다. 상기 조합된 신호는 앞서 설명한 과정과 동일하게 부 Y/C 신호처리부(220)내의 휘도신호 처리부(221)와 합성기(213)를 거쳐 상기 부헤드(2c)를 통해, 현재 기록되고 있는 첫 번째 필드신호에 이웃하여 영상트랙에 기록되게 된다.When all the color difference data in the 1H signal is read out from the memory 63a in which the color difference data is stored and converted into a compressed signal, the controller 100a applies a control signal CTL2 to the second multiplexer 72a to apply the color difference data. After the compressed signal (FIG. 4d) read out from the memory 63a stored therein is output through the second multiplexer 72a for a predetermined time, the control signal CTL2 is inverted so that the other memory 62a in which the luminance data is stored. In this case, the luminance signal (FIG. 4D) which is extended and read out in the above step is selected and output at the same time division ratio as above. In this way, the time division selected and output data is temporarily stored in the field memory 80a. The signal converted by the digital-to-analog converter 91a is frequency-modulated by a carrier having a conventional frequency in the existing luminance signal processor 211 and modulated analog corresponding to the luminance signal and the color difference signal of the first field. The signal is synthesized by the synthesizer 213 with a sine wave signal of a constant frequency described later and then recorded on the video tape by the main head 1c, while the second signal corresponding to the luminance signal and the chrominance signal of the subsequent field. Since the output data of the multiplexer 72a is recorded by the subhead 2c having a mounting angle difference of 120 ° from the main head 1c, after the main head 1c reaches the recording track of the tape, There is a need to delay the signal by the time interval at which the subhead 2c reaches the recording track. Therefore, the delay time corresponding to the 120 ° angle of the head drum is 11.1 ms (

175H), the data stored in the field memory 80a is read out at exactly the same speed as the time of recording exactly 11.1 ms after the start of recording, and is converted into an analog signal by the digital-to-analog converter 92a to be converted into an analog signal. Similarly, the luminance signal and the color difference signal are time-division combined signals. The combined signal is the first field currently being recorded through the subhead 2c via the luminance signal processor 221 and the synthesizer 213 in the sub Y / C signal processor 220 in the same manner as described above. It is recorded in the video track next to the signal.

6 is a symbol of a simplified configuration of a signal when a video signal selected by the signal selector 10a is recorded on the time axis, where ① is an output signal of the signal selector 10a, and ② is the image. The color signal is separated into two color difference signals by the signal decoder 20a, and ③ is a time-division combined signal having a luminance signal and a color difference signal through the decompression and compression processes described above, and two 1H signals The 2H signal is converted into two 2H signals, and the 2H signals have the signal configuration shown in FIG. The signal 3 in Fig. 7 extracts one chrominance signal at 1H and one chrominance signal different from the extracted chrominance signal at the next 1H signal, so as to reproduce the video signal in each 2H signal. The same color difference signal is used during the 2H period. That is, the two scanning lines use the same color signal vertically without distinguishing colors from each other. As shown in FIG. 7, the luminance of the higher frequency is obtained by securing more time intervals for the luminance signal. As a method for recording a signal by converting the signal to a low range, even if the vertical resolution of the less sensitive color is lowered, the horizontal resolution of the luminance signal that is sensitive to the eyes, i.e., greatly affecting the image quality, can be increased, thereby realizing high image quality.

FIG. 8 is a diagram illustrating a form in which a video signal selected according to the process described so far is recorded on a standard VHS video tape. Note '-A, -B' in the figure is defined by the main head 1c. -A and -B indicate that the subhead 2c is recorded.

On the other hand, the signal of a constant frequency synthesized in the synthesizers (213, 223) is a time reference signal that is recorded for accurate reproduction of the recorded signal is synthesized after the following process. From the luminance signal output from the signal selector 10a, a horizontal synchronizing signal is supplied to the synchronizing separator.

The sinusoidal wave signal separated by 110a, interlocked with the separated sync signal, and multiplied by 32.5 times its frequency is generated and output by the sinusoidal wave generator 111a. At this time, the generated sine wave is set lower than the frequency of the conventional color carrier carrier (629 kHz) for low frequency conversion so that interference with the frequency band of the video signal to be recorded does not occur. In the preferred embodiment of the present invention, 511.8 kHz was used. The sine wave of the selected constant frequency is recorded over the entire time zone with the video signal through the synthesizers 213 and 223 while minimizing the influence on the recorded video signal, and the PLL can be always applied without time interruption during playback. This will be described in detail in the high definition playback apparatus according to the present invention.

By using the preferred embodiment of the high-definition recording apparatus according to the present invention, it is possible to simultaneously record two different video signals (hereinafter, referred to as two-video recording), and the operation thereof is performed as follows.

First, unlike the case of the high quality recording, the control unit 100a directly inputs one of the input video signals (hereinafter, referred to as a first video signal) to a conventional video signal processing circuit to perform recording. On the other hand, the other video input signal (hereinafter referred to as a second video signal) is directly input to the analog-to-digital converter 41a to sample all signal sections with a clock of 4fsc, convert the digital data, and convert The output digital data is stored in the field memory 80a. The digital data stored in this way is read by the controller 100a after being delayed to meet the mounting angle of 120 ° with the main head 1c of the subhead 2c by the same time as that of the high quality recording. It is converted into an analog signal by the digital-to-analog converter 92a. The converted signal is subjected to the sub-Y / C signal processing unit 220, which is the same circuit as the main Y / C signal processing unit 210 in which the first video signal is processed, to obtain the luminance signal as in the conventional VHS recording apparatus. After the frequency modulation and the low frequency conversion of the color signal are performed, the subhead 2c is recorded adjacent to the first image signal.

Hereinafter, the configuration and operation of a preferred embodiment of the high quality reproduction apparatus according to the present invention for reproducing and outputting a high quality signal recorded as shown in FIG. 8 will be described in detail.

9 is a block diagram of a preferred embodiment of a high quality reproduction apparatus according to the present invention, including conventional luminance signal processing units 211 and 221 and color signal processing units 212 and 222 for processing signals reproduced by a head; Switches (231, 2) for selecting the color signal output of the color signal processing unit (212, 222)

32); Frequency detectors (1b, 3b) for detecting a constant frequency signal from the output signal of the latitude signal processor (211,221); Reference clock generators 2b and 4b for outputting a time reference signal multiplied by the detected frequency; The main Y / C signal processing unit 210 and the sub Y / C signal processing unit by the reference clock.

Analog / digital converters 11b and 12b respectively converting two analog signals output from 220 into digital data; A field memory (20b) for storing the converted data at the same conversion rate as the analog / digital converter (11b); The data read out from the field memory 20b and the conversion data of the analog / digital converter 12b are used as control signals CTL3.

First and second demultiplexers 31b and 32b which are separated into chrominance data and luminance data, respectively and output separately; A luminance data memory (41b, 43b) for storing the luminance data among the data separated by the first and second multiplexers (31b, 32b) at the same as the conversion speed; Color difference data memories 42b and 44b respectively storing color difference data among the separated data at the same conversion rate; The luminance data memories 41b and 43 which are read at a speed higher than the storage speed.

a multiplexer 50b for alternately selecting and outputting data of b) according to the control signal CTL4; A color signal encoder 60b which encodes data of the color difference data memories 42b and 44b which are respectively read out at a slower speed than a storage speed into a color signal; Digital / analog converters 71b and 72b for converting output data of the multiplexer 50b and the color signal encoder 60b into analog signals, respectively; A signal synthesizer 80b for synthesizing the converted analog signal and outputting a high quality video signal; And outputting the control signals CTL4 and CTL5 according to signals of a predetermined frequency extracted from the frequency detectors 1b and 3b, and outputting a control signal CTL3 for separating luminance data and color difference data according to a predetermined time ratio. A controller (100b) for adjusting a data storage time of the field memory (20b); It is configured to include.

In the high quality playback apparatus according to the present invention configured as described above, first, the switches 231 and 232 are controlled by the controller 100b to control the color signal processing units 212 and 22.

The processing signal of 2) is not output. In this state, when the signal is reproduced and output by the main head 1c, the frequency signal demodulation is performed by the luminance signal processing unit 211. The demodulated signal is converted into digital data by the analog / digital converter 11b and stored in the field memory 20b. The data stored in the field memory 20b is equal to the time taken from the subhead 2e to start playing the signal containing the video information of the adjacent field, that is, 11.1 ms (corresponding to 175H). It is read at a speed and input to the first demultiplexer 31b. The signal reproduced from the subhead 2e is also subjected to the demodulation process and the analog / digital conversion process, and is input to the second demultiplexer 32b at the same time as the signal delayed from the field memory 20b. . Data input to the first and second demultiplexers 31b and 32b, respectively, is a data string as shown in FIG. The controller 100b applies a control signal CTL3 for selecting an output terminal at a predetermined time rate to the first and second demultiplexers 31b and 32b and inputs the first and second demultiplexers 31b and 32b. The color difference data and the luminance data are separately output from the data. The luminance data separately output is luminance data memory (41).

b and 43b, the color difference data is stored in the color difference data memories 42b and 44b at the same speed as the analog / digital conversion rate.

The two luminance data columns of the stored data are read out at a faster speed (4fsc) than the recording (520f _h ) and compressed into the original luminance signals, as opposed to the signal extension in the recording apparatus described above, and the two color difference data columns are compressed. On the contrary, it is read at a slower speed fsc than at storage 520f _h and expanded to the original color difference signal. As described above, the two luminance data columns to be read out are interpolated for each 1H section by the multiplexer 50b which alternately selects and multiplexes an input by the control signal CTL4 of the controller 100b. Then, the data is restored to data representing a normal luminance signal, which is converted into an analog luminance signal by the digital-to-analog converter 71b and output. On the other hand, the two color difference data columns extended and read from the color difference data memories 43b and 44b are used to color the color difference data input by the color signal encoder 60b according to the control signal CTL5 of the controller 100b. The signal is converted into a signal and maintained for 2H, and output as a data string as ⑤ in FIG. Since the output data of the color signal encoder 60b is already coincident with the correlated luminance data output from the multiplexer 50b during the conversion process, this data is analogized by the digital-to-analog converter 72b. By converting to a color signal, the converted analog luminance signal and the signal synthesizer 80b are synthesized to restore a complete video signal as shown in FIG.

On the other hand, 511.8 kHz (3 from the signal output from the Y / C signal processing unit (210, 220)

A constant frequency signal of 2.5 f _h ) is detected by the frequency detectors 1b and 3b and input to the reference clock generators 2b and 4b, and the reference clock generators 2b and 4b are synchronized in phase with the input signal. And the frequency is outputted the correct reference clock multiplied (16 times) by 520f _h . This signal is used as a reference clock for digital data processing. Since this clock signal is an accurate signal without phase shift by a signal of a constant frequency of 32.5f _h , which is always input, the Y / C signal processing unit 210 or 220 The original signal recorded as it is can be restored without being distorted and outputted.

FIG. 11 shows the difference between the present invention in which a reference signal is always input to a phase locked loop (PLL) during reproduction and the prior art output signal in which a lift signal is input at a predetermined time. In the digital signal processing, the signals output from the Y / C signal processing units 210 and 220 are not distorted at all and are restored as they are, since signals are sampled, stretched and compressed at an accurate time interval, and converted into analog signals. The technique allows the frequency of the time reference signal available for signal processing to be varied during periods when the PLL is not in college. As shown in FIG. 11, when the time reference signal changes and the sampling price fluctuates, the digital value at the sampling time is sampled differently from the recording time. (A portion of FIG. 11) Such a shape is converted at the time of converting the signal output from the Y / C signal processing unit 210 or 220 by analog again to analog again at a constant frequency. The same signal distortion occurs even if the input clock for that point is changed.

However, since the frequency shift of the reference clock does not occur in the playback apparatus according to the present invention in which a constant reference signal is always generated by the phase-locked loop over the entire time of playback, the reproduced signal is completely restored to the original signal without signal distortion. Will be.

In the above-described recording apparatus according to the present invention, if two-video recording is performed instead of high-definition recording, the control unit 100b controls the switch (

231 and 232, respectively, so that the color signal inversely low-converted by the color signal processing unit 212 and 222 is combined with the luminance signal demodulated by the luminance signal processing unit 211 and 221, and the synthesized signal is directly externally processed without a separate signal processing process. Each of the two video signals can be outputted to the video display device. In this case, unlike the case of recording, the luminance and color signals may be processed and output without delaying the signals output from the main head 1c and the subhead 2c.

The high-definition recording and reproducing apparatus using the standard VHS video tape according to the present invention, which is constructed and operated as described above, uses more than about 400 copies while using the standard VHS video tape and the existing luminance and color signal processing circuits as they are. It is a breakthrough and very useful invention that can record and reproduce high quality video signals with resolution and wide color band of 1.2MHz.

In addition, the PM noise of the color signal, which can be seen in the color frequency processing of the reference frequency low-frequency conversion method, is significantly improved, thereby ensuring excellent color signal performance with broadband processing. In particular, the selection and time allocation of luminance and color signals that optimally distribute the vertical resolution of the color signal and the horizontal resolution of the luminance signal enable the realization of the maximum image quality in a limited bandwidth. By performing the phase correction, complete signal restoration without distortion of the reproduced signal is also possible, and using the recording and reproducing apparatus according to the present invention, it is possible to record and reproduce two separate video signals, respectively. It is very economical compared to using a regeneration device.

Claims (7)

A video recording / playback apparatus using standard VHS videotape, comprising: signal separation means for separating a received video signal into one luminance signal and a plurality of color signals; Signal compression means for alternately selecting and compressing the plurality of color signals; Signal extending means for sequentially dividing the luminance signal into first and second luminance signals according to horizontal synchronization; First converting means for time-division selecting the extended first luminance signal and the compressed color signal and converting the converted first luminance signal into a single signal; Second converting means for time-dividing the expanded second luminance signal and the compressed next color signal into a single signal; And delay means for delaying outputting the converted signal of the second conversion means for a predetermined time. 2. The apparatus of claim 1, further comprising: detection means for detecting a synchronization signal of the video signal; And reference signal generating means for generating and outputting a constant frequency signal interlocked with the detected synchronization signal. The high definition recording apparatus of claim 2, wherein the predetermined frequency is 629 kHz or less. The high definition recording apparatus of claim 1, wherein the time division ratio is 4: 1. The high definition recording apparatus of claim 1, wherein the predetermined time is 10.7-11.4 msec. An image recording / playback apparatus using standard VHS videotape, comprising: delay means for delaying all channel signals of a two-channel signal input for a predetermined time; First separating means for separating a luminance signal and a color signal from a later channel signal of the two channel signals; Second separating means for separating the luminance signal and the color signal from the delayed signal; Luminance signal recovery means for compressing the separated luminance signals, alternately selecting the luminance signals, and outputting them as a single signal; Color signal recovery means for repeating outputting each of the separated color signals once and then repeating the outputs; And image signal converting means for converting the output luminance signal of the luminance signal restoring means and the plurality of output color signals of the color signal restoring means into a composite video signal. 8. The apparatus of claim 6, further comprising: detecting means for detecting a constant frequency signal in the reproduced two-channel signal; And control means for adjusting signal processing speeds of the delay means, separation means, and recovery means based on the detected signal. High definition playback device is configured to include more.

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