KR0170647B1 - Recording/reproducing apparatus and method - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital recording and reproducing apparatus and method for recording and reproducing digital data. In particular, the present invention provides a method for optimally performing recording and reproducing according to changes in the recording and reproducing environments of data. A first memory, a modulator for modulating the data read out from the first memory according to channel characteristics, a first amplifier for amplifying a recording signal modulated by the modulator to a predetermined size and supplying it to a recording head and a recording medium. A second amplifier for reproducing the recorded recording signal using a reproduction head and amplifying the recording signal to a predetermined size, and outputting an equalizer and an equalizer for compensating for degradation of a frequency characteristic, etc. of the reproduction signal amplified by the second amplifier. A demodulator for demodulating according to channel characteristics, a second memory for storing a signal demodulated by the demodulator, and stored in the first memory and the second memory. When compared to the emitter recorded in adjusting the degree of amplification in the first amplifier and reproduction, it includes a recording and reproduction signal adjusting unit for adjusting the compensation in an equalizer.

Description

Optimal recording and playback apparatus and method

1 is a block diagram of a conventional digital recording apparatus.

1 is a diagram showing the relationship between the distance between the head and the tape and the reproduction output in the set device.

2 is a diagram showing the relationship between the type of tape and the reproduction output.

3 is a diagram showing the relationship between the magnetic material thickness of the tape and the reproduction loss.

4 shows the relationship between recording current and reproduction characteristics.

5 is a diagram showing a relationship between a recording bit rate and reproduction characteristics.

6 is a schematic block diagram of a conventional digital signal recording apparatus.

7 is a schematic block diagram of a conventional digital signal reproducing apparatus.

8 is a schematic block diagram of one embodiment of an optimum recording and reproducing apparatus according to the present invention;

9 is a block diagram of a recording / playback adjusting section according to the present invention of FIG.

FIG. 10 is a block diagram of the recording adjustment unit of FIG.

FIG. 11 is a block diagram of a first amplifier part in FIG.

FIG. 12 is a block diagram of a reproduction adjusting unit of FIG.

13 is a block diagram of the equalizer of FIG.

14 to 22 are graphs showing the results of simulation in the optimum recording and reproducing apparatus according to the present invention.

* Explanation of symbols for main parts of the drawings

10: A / D converter 15: Encoder

20 modulator 25 first amplifier

27: second amplifier 30: demodulator

35: decoder 40: D / A converter

60: recording and playback adjusting section 50, 55: first and second memories

70: equalizer 90: record adjustment unit

95: playback adjustment unit 140: delay adjustment unit

150: amplification control unit

The present invention relates to a digital recording and reproducing apparatus and method for recording and reproducing digital data. In particular, the present invention relates to an optimal recording and reproducing apparatus and method for optimally performing recording and reproducing according to changes in the recording and reproducing environments of data. It is about.

Generally, in recording and reproducing sound or video data, these data are stored in a recording medium such as magnetic tape or magnetic disk in the form of digital signals, and the recorded data is reproduced to restore the original image and sound. As described above, in recording and reproducing image and audio data on a predetermined recording medium, an effort is made to increase the amount of data to be recorded on a limited-size medium and to obtain better image quality and sound quality without deterioration in image quality or sound quality during reproduction. This is going on.

However, since the conventional digital playback apparatus is basically configured to record and reproduce data with a fixed recording rate, error correction capability, and a fixed compression rate in a constant state, image quality and sound quality are dependent on the characteristics of the recording medium and the performance of the set apparatus. There was a problem in that the optimal recording and reproducing was not possible because the condition of.

In addition, the head, which is an important element of the device used for recording and reproducing data, is produced well, the performance of the tape used is the same, the set devices are all the same, and even if they are manufactured in the same production line, The performance of tens of thousands of sets of heads cannot be the same, and even recording or playing back the same image and sound data cannot guarantee the same sound quality and image quality. Therefore, there is a problem that not only brings a difference in image quality and sound quality depending on what set apparatus and tape are used, but also in some cases, deterioration in image quality and sound quality.

The problems as described above will be described with reference to FIGS. 1 to 5, which are practical experimental data.

FIG. 1 shows the relationship between the reproduction loss according to the distance between the head and the recording medium tape in the set apparatus. As shown in FIG. 1, the closer the distance between the head and the tape, the larger the reproduction output. In this way, even if the set apparatus is the same, it can be seen that there is a difference in the reproduction output depending on the minute distance change between the head and the tape.

2 shows the relationship between the type of tape and the reproduction output. In the example shown in FIG. 2, it is shown that a tape (NEW ME) having a component of Hc = 1680 (Oe) and Br = 4050 (Oe) has the best characteristics. Even when recording and reproducing is performed with the same apparatus as described above, it can be seen that there is a difference in reproduction output depending on the composition of the components constituting the tape on which data is recorded.

3 shows the relationship between the thickness of the magnetic material of the tape and the reproduction loss. 3 shows the difference in regeneration loss when the thickness of the magnetic material of the tape is 0.20 μm and 0.25 μm, respectively, and the regeneration loss is smaller than 0.25 μm when the thickness of the magnetic material of the tape is 0.20 μm. . In other words, it can be seen that, as an example of the above, when the tape is thin, the reproduction loss is small.

4 shows the relationship between the recording current and the reproduction characteristics. As shown in Figs. 4A, 4B and 4C, even in the case of the same recording signal, it can be seen that the reproduction characteristics are different even if the recording current is slightly adjusted in the set.

5 shows the relationship between the recording bit rate and the reproduction characteristics. As shown in Figs. 5A, 5B, and 5C, the lower the recording bit rate, the better the reproduction characteristics, and this characteristic also varies depending on the type of tape used, the performance of the recording head, the recording current, and the like.

As described above, the operation of the conventional digital signal recording and reproducing apparatus without considering the characteristics of the tape, the head, the set equipment, and the like will be briefly described with reference to the block diagrams of FIGS.

6 is a schematic block diagram of a conventional general digital recording apparatus. 6 is an A / D converter for converting an analog input signal into a digital signal, 15 is an error correction encoder for error correction, 20 is a modulator for modulating data to match channel characteristics, and 25 is a data signal. A first amplifier section that amplifies to an appropriate size for recording on a recording medium.

Since the image or sound data input to the digital signal recording apparatus shown in FIG. 6 is in the form of an analog signal, it is converted into a digital signal using the A / D converter 10 for digital processing thereof. The converted data is input to an error correction encoder 15 which detects and corrects an error for error correction. The error correction encoder 15 generally uses an R-S coder (Read Solomon Coder).

The error correction data is modulated in accordance with the characteristics of the channel in the modulator 20. That is, if digital data is data for communication, the data is frequency-modulated in a communication frequency band, and in the case of data for recording on a medium such as a magnetic tape, the data is modulated in a frequency band suitable for recording. The digital data modulated according to the characteristics of the channel as described above is amplified to an appropriate size in the first amplifier 25 and recorded on the recording medium.

7 is a schematic block diagram of a conventional general digital recording and reproducing apparatus. 7 to 25 are second amplifiers having the same role as those in the recording apparatus in FIG. 6, 30 to demodulate to perform the reverse process of modulation that was performed at the time of recording, and 35 to decoder to decode input data. 40 is a D / A converter for converting a digital signal into an analog signal.

In the digital signal reproducing apparatus shown in FIG. 7, the image or audio digital data reproduced on the recording medium using the head is input to the second amplifier 27 and amplified into a signal having a predetermined size. The amplified signal demodulates the input data by performing a demodulation process corresponding to an inverse process of the modulation performed at the time of recording by the demodulator 30. The demodulated data detects an error in the error correction decoder 35 and performs error correction. As the error correction decoder 35, a Viterbi decoder or an R-S decoder is used. The image or sound digital data with error correction is converted into an analog signal by the D / A converter 40 and transmitted to a display device or a speaker so as to be output in the form of an image or sound.

As described above, the general digital recording / reproducing apparatus shown in FIGS. 6 and 7 performs recording and reproducing of data with the data recording rate and the length of the track of the recording medium fixed. In addition, deterioration of image quality and sound may occur depending on a difference in characteristics of a recording medium or performance of a system set.

In addition, since most electric and electronic products are mass-produced, even if the same type of head, tape or system set used as a recording medium is used, the performances of the same products cannot be the same. As a result, it is difficult to record data at an optimal density during recording, and there is a problem that sound quality and image quality deteriorate because recorded data is not optimally reproduced even during reproduction.

Accordingly, it is an object of the present invention to provide an optimal recording and reproducing apparatus and method for recording and reproducing images and audio data in an optimal state regardless of the performance of a recording medium, a system set, or the like.

In order to achieve the above object, the optimal recording and reproducing apparatus of the present application is a recording and reproducing apparatus for recording digital data on a predetermined recording medium by using a recording head and reproducing and outputting the recorded data by using a reproduction head. A first memory for storing a digital data signal; A modulator for modulating data read from the first memory according to channel characteristics; A first amplifier for amplifying the recording signal modulated by the modulator to a predetermined size and supplying the recording signal to the recording head; A second amplifier for reproducing a recording signal recorded on the recording medium by using a reproduction head and amplifying the recording signal to a predetermined size; An equalizer for compensating for deterioration such as frequency characteristics of the reproduced signal amplified by the second amplifier; A demodulator for demodulating the output of the equalizer according to channel characteristics; A second memory for storing the demodulated signal by the demodulator; And a recording / playback adjusting section for comparing the data stored in the first memory and the second memory to adjust the amplification degree in the first amplifier section during recording and to adjust the signal compensation in the equalizer during playback.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

8 is a block diagram of an optimum recording and reproducing apparatus according to the present invention.

In FIG. 8, the modulator 20, the first amplifier 25, the second amplifier 27, the demodulator 30, the error correction encoder 15 and the error correction decoder 35 are shown in FIG. The same function as that used in the conventional digital signal recording and reproducing apparatus shown in FIG. 7 may have some differences in signal processing. 50 is a first memory for temporarily storing an input digital recording signal, and 55 Second memory for temporarily storing the digital reproduction signal output from the error correction decoder 35, 60 is a recording and playback adjusting unit for reproducing the state of the signal to be recorded or reproduced, 70 is an equalizer for compensating for degradation such as frequency characteristics to be.

The operation of the optimum recording and reproducing apparatus according to the present invention having the configuration as described above is as follows.

First, an example of the case where data is recorded will be described.

After performing the signal processing internally, the digital input signal to be recorded on the recording medium is temporarily recorded in the first memory 50 and the data read from the memory 50 is corrected to correct an error that may occur during the input data. After encoding by the error correction encoder 15, it is input to the modulator 20 and modulated to suit the channel characteristics. The modulated signal is amplified to a predetermined size by the first amplifier 25 to be recorded on the recording medium and transmitted to the recording head for recording on the recording medium.

At the time of recording the data by the recording head, the data is immediately reproduced by the reproduction head following the recording head and simultaneously input to the second amplifier 27. The signal amplified by the second amplifier 27 to a predetermined magnitude is input to the equalizer 70 to compensate for deterioration such as frequency characteristics, and then the signal is input to the demodulator 30 and demodulated.

The demodulated signal is input to the error correction decoder 35 and stored in the second memory 55 which temporarily specifies the data for reproduction after the data is decoded. As described above, when data input to the first memory 50 for recording data is reproduced simultaneously with recording and input to the second memory 55, the recording / playback adjusting unit 60 reads the data stored in these memories and compares them with each other. Then, the parameters of the first amplifier 25 and the equalizer 70 are adjusted according to the comparison result to find the optimal recording / playback parameter and perform recording / playback of the data.

In this way, an operation performed by the recording / playback adjusting unit 60 according to the present invention for determining the parameter for optimal recording / playback of data will be described with reference to FIG.

9 shows an internal block diagram of the recording and reproducing section of the optimum recording and reproducing apparatus according to the present invention. In FIG. 9, 75 denotes an address counter for storing specific addresses on the first memory 50 and the second memory 55, and 80 indicates whether data read from the first memory 50 and the second memory 55 match. The comparator 85 for comparing the data, 85 is a counter for counting the comparison result, and 90 and 95 are recording and reproducing adjustment parts for adjusting the recording or reproducing state of data according to the counted result.

The operation of the recording / playback adjusting unit 60 having the above configuration will be described below.

As shown in FIG. 9, the digital recording data signal input from the outside and recorded in the first memory 50 and the digital reproduction data signal recorded in the second memory 55 through the playback process at the same time as the recording are recorded in the address counter 75 The digital data recorded at a specific position in the memory is output in accordance with the address data designated by the "

Digital data output from the first memory 50 and the second memory 55 is input to the comparator 80. The comparator 80 compares the input data with each other to determine whether the same is the same and outputs a comparison result signal. The signal output from the comparator 80 is input to the counter 85, and the counter 85 counts only the data signal outputted when both of the signals output from the comparator do not coincide with each other to obtain the number of errors.

The number of errors counted by the counter 85 is input to the recording adjusting unit 90 and the reproducing adjusting unit 95 to adjust the state of the signal to be recorded and the signal to be reproduced. That is, the output from the recording adjustment unit 90 is input to the first amplifier 25 to adjust the degree of amplification of the signal to be recorded, and the output of the reproduction adjustment unit 95 is input to the equalizer 70 to Compensate for degradation and adjust for optimum regeneration.

Thus, the configuration and operation of the recording adjustment unit 90 and the reproduction adjustment unit 95 will be described in detail with reference to FIG. 10 and FIG.

FIG. 10 shows the recording adjuster 90, where 110 and 115 are first and second buffer memories for temporarily storing data, 120 is a gate serving as a passage for signal transmission, 130 is a comparator, and 135 is an up / down The operation of the recording adjustment unit 90 having such a configuration as a counter is as follows.

After storing the number of errors output from the counter 85 in the recording / playback adjusting unit 60 in FIG. 9 in the first buffer memory 110, the value of the number of previous errors recorded in the second buffer memory 115 is stored. Comparison is made in the comparator 130. The comparator 130 controls the control signal to the gate 120 only when the number of previous errors recorded in the second buffer memory 115 is greater than the current number of errors recorded in the first buffer memory 110. To pass through the gate 120 to store the current error number stored in the first buffer memory 110 in the second memory 115, and at the same time the output of the comparator 130 up-down counter ( 135 to increase the count value by the up-down counter 135.

In addition, when the number of errors recorded in the first buffer memory 110 and the second buffer memory 115 is compared by the comparator 130, when the values are the same, the up-down counter 135 is the current value. If the number of previous errors is smaller than the number of current errors as a result of the comparison, the count value of the up-down counter 135 is reduced by one and the value is transmitted to the first amplifier 25 to be described later. .

In this way, the output of the recording adjustment unit is input to the first amplifier 25 to adjust the degree of amplification. The configuration of the first amplifier 25 according to the present invention will be described with reference to FIG.

As shown in FIG. 11, the recording signal modulated from the modulator 20 to suit the channel characteristics is connected to the inverting terminal of the first amplifier 150, the non-inverting terminal of the first amplifier is grounded, and the first amplifier unit is grounded. The output of (25) is fed back and connected to the non-inverting terminal of the first amplifier 150. The output terminal of the first amplifier 150 is connected to the switching unit 160 and the switching unit 160 is configured to be selectively connected to a plurality of resistors.

When the output of the up / down counter 135 in the recording adjustment unit 90 shown in FIG. 10 is human to the switching unit 160, the output of the up / down counter 135 is output from the modulator 20 according to the magnitude of the applied output. As the position of the connection point to which the signal amplified by the amplifier 150 to a predetermined size is switched by the switching unit 160 is changed, the amplification of the signal output by the resistors having a specific size in the connected resistance unit is changed. The degree is adjusted and output to a recording head or the like for recording signals. In addition, the outputted recording signal is connected to the non-inverting terminal of the first amplifier 150 through the second amplifier 155 which serves as a buffer separately.

As described above, the input digital signal is amplified by the first amplifier 25 at a predetermined amplification factor at the time of initial recording, but is reproduced by a reproduction head at the same time as recording and then reproduced through a general reproduction process. After comparing the signals and counting the degree of inconsistency with each other, the amplification degree of the recorded signals can be changed according to the change of these count values so that the signals to be recorded can be recorded in an optimal state.

And the reproduction adjusting unit 95 shown in FIG. 12 is almost the same as the configuration of the recording adjusting unit 90 in FIG. 10, the difference is that the inverter 140 further includes an inverter 140 at the output terminal of the comparator 130. Up / down counters 145 using the other output via () are configured to be further connected, thereby inverting the value of comparator 130 using inverter 140 and operating two counters by operating one counter. To print. At this time, one output from the two outputs to the delay adjusting unit 140 of the equalizer 70 to be described later, and the signal output from the up-down counter 145 through the inverter 140 is an amplification adjusting unit ( 150).

The signal output from the reproduction control unit 95 is applied to the equalizer 70 to equalize the signal amplified by the second amplifier 27, which is described with reference to the configuration of the equalizer 70 according to the present invention of FIG. Explain.

The equalizer 70 in FIG. 13 is composed of a delay adjusting unit 140 composed of a plurality of delay elements D1, D2, ..., DN, and a plurality of resistance elements R1, R2, ..., RN. Amplification control unit 150 for adjusting the degree and the amplifier 160 for receiving and amplifying the output of the amplification adjustment unit 150 and looks at the operation as follows.

That is, the reproduction output amplified by the second amplifier 27 is input to the delay adjusting unit 140 and the signals output from the up / down counters 135 and 145 of the recording / playback adjusting unit 60 are inversely proportional to each other. Input to the delay adjusting unit 140 and the amplification adjusting unit 150 of the equalizer 70, respectively. By the input of the signals inversely proportional to each other, the selection process of the delay element and the amplification adjustment element in the delay adjustment unit 140 and the amplification adjustment unit 150 is reversed. Therefore, when the value of the delay element increases, the value of the amplification adjustment element decreases. That is, the signal output from the second amplifier receives any one of the delay elements of the delay adjustment unit 140 by the signal input from the signal amplification delay adjustment unit 140 output from the reproduction adjustment unit 95 of the recording and reproduction adjustment unit 60. Drive the amplified signal for a predetermined time, and at the same time, it is input to the amplification control unit 150 to drive any one of the amplification elements according to the amplification adjustment signal to adjust the amplification degree of the delayed output and output the signal through the amplifier 160. Amplified to equalize the signal.

The equalized reproduction signal performs the reverse process of the modulation process performed in the recording process by the demodulator 30 shown in FIG. 8, and the demodulated signal is input to the ECC decoder 35 to perform an error correction decoding process. It is output after being temporarily stored in the memory 55 after execution.

A brief description will be given with reference to the graphs shown in FIGS. 14 and 22 showing the results of the simulation in the optimum recording / reproducing apparatus according to the present invention having the above configuration. 14 to 16 and 17 to 19 show the simulation results when the recording current is 20 mA and 27 mA, respectively, and it can be seen that the reproduction amplitude is large when the recording current is 27 mA. 14, 15, and 16, the amplitude ratio of the regenerative equalizer is 10% and 25% of the reference amplitude. The reproduction amplitude and phase shift at 50% are shown. As the amplitude ratio is increased, the output level of the moving device decreases and the phase shift amount also decreases.

20 to 22 show the change in amplitude and hygiene variation of the regenerative equalizer when the value of the delay element of the regenerative equalizer is 0.5 clock, 1 clock, and 2 clock, respectively. It can be seen that the amplitude value of the output of the instrument increases, but the amount of phase shift increases.

The present invention can be applied in various ways to select the amplification factor during recording amplification in addition to those described above by using a switch, a relay, a switching IC, or the like, when a special key (automatic setting function) is input. It is possible to configure to have different embodiments depending on whether to operate only or to operate in normal operation. Further, not only the configuration method and selection method of the delay element of the reproduction equalizer, but also the configuration method and selection method of the amplitude composition element can be configured in other embodiments.

As described above, the present invention has an effect of recording / reproducing in an optimal state regardless of the performance of the material of the recording medium, the system set, or the like in recording and reproducing images and audio data.

Claims (17)

A recording and reproducing apparatus for recording digital data on a predetermined recording medium by using a recording head and reproducing the recorded data by using a reproduction head, comprising: a first memory for storing an input digital data signal; A modulator for modulating data read from the first memory according to channel characteristics; A first amplifier for amplifying the recording signal modulated by the modulator to a predetermined size and supplying the recording signal to a recording head; A second amplifier for reproducing a recording signal recorded on the recording medium by using a reproduction head and amplifying the recording signal to a predetermined size; An equalizer for compensating for degradation of a frequency characteristic or the like by reproducing the signal amplified by the second amplifier; A demodulator for demodulating the output of the equalizer according to channel characteristics; A second memory for storing a signal demodulated by the demodulator; And a recording / playback adjusting section for comparing the data stored in the first memory and the second memory to adjust the amplification degree in the first amplifier section during recording and to adjust the signal compensation in the equalizer during playback. Optimal recording and reproducing apparatus. 2. The apparatus of claim 1, wherein the recording / playback adjusting section comprises: an address counter for generating an addressing instruction designating a specific address of the first memory and the second memory; A comparator for comparing contents recorded in the first memory and the second memory by an address designation command designated from the address count; A counter for counting comparison results by the comparator; A recording adjusting unit for adjusting the recording degree of the recorded signal according to the number of errors counted in the count; And a reproducing adjusting section for adjusting a reproducing operation of a signal to be reproduced in accordance with the number of errors counted in the counter. 3. The apparatus of claim 2, wherein the recording controller comprises: a first buffer memory for storing the number of input errors; A second buffer memory for storing the number of previously inputted errors; A comparator for comparing the number of errors recorded in the first buffer memory and the second buffer memory; A gate controlling the transfer of the number of errors recorded in the first buffer memory to the second buffer memory according to the comparison result; And a counter for up / down counting the counted value according to the comparison result. The method of claim 3, wherein the gate is written to the first buffer memory when the number of errors recorded in the first buffer memory is smaller than the number of errors recorded in the second buffer memory as a result of the comparison in the comparator. An optimal recording and reproducing apparatus, characterized in that it is opened for transferring the value of the number of errors to the second buffer memory. The counter of claim 3 or 4, wherein the up / down counter is up when the number of errors recorded in the first buffer memory is smaller than the number of errors recorded in the second buffer memory as a result of the comparison in the comparator. And counting, maintaining the current state if the count is the same, and down counting if the count is large. The apparatus of claim 2, wherein the reproducing controller comprises: a first buffer memory for storing the number of input errors; A second buffer memory for storing the number of previously inputted errors; A comparator for comparing the number of errors recorded in the first buffer memory and the second buffer memory; A gate controlling the transfer of the number of errors recorded in the first buffer memory to the second buffer memory according to the comparison result; A first counter which up / down counts the counted value according to the comparison result; An inverter for inverting the output of the comparator; And a second counter which up / down counts the counted value according to the output inverted by the inverter. The method of claim 6, wherein the gate is written to the first buffer memory if the number of errors written in the first buffer memory is less than the number of errors written in the second buffer memory as a result of the comparison in the comparator. An optimal recording and reproducing apparatus, characterized in that it is opened for transferring the value of the number of errors to the second buffer memory. The counter of claim 6 or 7, wherein the first counter is up counted when the number of errors recorded in the first buffer memory is smaller than the number of errors recorded in the second buffer memory. If it is the same, the current state is maintained, and if it is large, the down count is performed, and if the number of errors recorded in the first buffer memory and the second buffer memory is different, the second counter is used. An optimal recording and reproducing apparatus characterized by performing a count operation as opposed to a counter. 7. The apparatus of claim 6, wherein the equalizer comprises: a delay adjuster for variably delaying a signal amplified through the second amplifier according to the output of the first counter of the regenerative adjuster; An amplification adjustment unit for amplifying the signal delayed by the delay adjustment unit according to the output of the second counter of the reproduction adjustment unit; And an amplifier for amplifying the signal whose amplification degree is adjusted by the amplification adjusting unit. 10. The optimum recording and reproducing apparatus according to claim 9, wherein a delay degree and an amplification degree made in said delay adjusting section and said amplifying adjusting section are inversely proportional to each other. The recording apparatus of claim 1, wherein the recording amplifier comprises: an amplifier for comparing and amplifying the recording signal modulated by the modulator with a previously modulated recording signal; Switching means for switching the signal amplified by the amplifier in accordance with a switching control signal from the recording / playback adjusting section; An amplification adjusting unit for selectively adjusting the amplification degree of the signal input by the switching means to output a recording signal to be recorded on the recording medium; And a buffer which buffers the signal output by the amplification controller and supplies the amplifier to the amplifier. 12. The optimum recording and reproducing apparatus according to claim 11, wherein said amplification adjusting section includes a plurality of resistors selectively connected in accordance with a switching control signal from said recording and reproducing adjusting section. A recording and reproducing method for recording digital data on a predetermined recording medium by using a recording head and reproducing the recorded data by using a reproduction head, the method comprising: storing input digital data; Amplifying the stored data to a predetermined size for recording on a recording medium after modulation to conform to channel characteristics; Storing the reproduced data by simultaneously reproducing the recorded data on the recording medium of the amplified data; Comparing the data stored at the input with the data stored at the reproduction; And controlling the amplification degree of the recording signal in the amplifying step according to the comparison result. The method of claim 12, wherein the comparing comprises: comparing whether data stored at the input and data stored at the reproduction match; Counting only cases where data compared in the comparing step is different from each other; And adjusting a signal to be recorded and reproduced according to the number of errors counted in the counting step. 15. The method of claim 14, wherein the recording adjustment step comprises: comparing the number of current counted errors with the number of previously counted errors; And controlling the amplification of a signal to be recorded on the recording medium by performing an up / down count according to the comparison result in the comparing step. 15. The method of claim 14, wherein the step of adjusting playback comprises: comparing the number of current counted errors with the number of previously counted errors; And controlling the degree of delay and amplification of the signal reproduced from the recording medium by the up counted down signal and the down counted signal by simultaneously performing the up / down count according to the comparison result in the comparing step. Optimal recording and playback method. 17. The optimal recording and reproducing method according to claim 16, wherein the delay and amplification of the signal in said control step are inversely related to each other.