JP2000215604A - Data recording system, data recording apparatus, and data reproducing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To record AUX data on a recording medium while realizing perfect compatibility with a recording and reproducing system by adding auxiliary information, which corresponds to a bit difference between two predetermined bit numbers to main information for each of compressed recording units, and generating a recording unit having a first predetermined bit number by using divided main information and the auxiliary information to be added thereto. SOLUTION: A data compression/expansion circuit compresses audio data, and upon their transmission to an MPX, constitutes a sound group (recording unit) of the compressed data so as to allow an AUX data to be added thereto. The sound group, which is a time-series data corresponding to an audio signal of one unit, is composed of a sound parameter, a word length, a scale factor, audio spectrum data, and AUX data, and fixed to be an N bytes similarly to the sound group. The amount of data of each of the sound groups is equally N bytes, and therefore, troubles or the like at the data transfer are not generated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data recording system for recording and reproducing data on a disk recording medium such as a mini disk, a data recording device, and a data reproducing device.

[0002]

2. Description of the Related Art In recent years, an audio signal recording / reproducing system has been shifted from an analog system to a digital system. As recording media for recording digital audio signals, compact discs (hereinafter abbreviated as CDs) as read-only optical discs and mini discs as magneto-optical discs capable of recording / reproducing / erasing are used as recording media for consumer use. (Hereinafter, abbreviated as MD) and the like have been developed.

[0003] Compared to CD, MD has a CD having a diameter of CD.
, And the reduced size ensures the same amount of information recording capacity as a CD. Therefore, the digital audio signal recorded on the MD is A
Data is compressed to about １ ／ by an audio efficient coding method called TRAC (Adaptive Transform Acoustic Coding).

FIG. 3 shows a configuration of a mini disk device as an example of a conventional recording / reproducing device.

[0005] The mini-disc device can record audio data after compressing the audio data and modulating the compressed audio data to be recorded on the MD as a recording medium, and can reproduce the data recorded on the MD into the original audio data. / Reproducing device.
The mini disk device includes an optical pickup 51, an RF amplifier 52, an encoder / decoder / signal processing circuit 53,
Memory controller 54, shockproof memory 5
5, a data compression / expansion circuit 56, an AD / DA converter 57, a feed motor 58, a spindle motor 59, a drive circuit 60, a servo circuit 61, and a system controller 62.

The feed motor 58 is provided with the optical pickup 5
1 is a motor for moving 1 in a direction orthogonal to the tracks of the mini-disc 63. The spindle motor 59 is
This is a motor for rotating the mini disk 63. The drive circuit 60 supplies power to the feed motor 58, the spindle motor 59, and the objective lens 51a of the optical pickup 51 in order to drive them.

The servo circuit 61 performs a servo operation such that the light emitted from the optical pickup 51 follows a target track of the mini-disc 63 accurately.
The above-described devices driven by the drive circuit 60 are feedback-controlled. The servo circuit 61 determines the control amount of each device based on the output of the RF amplifier 52,
The control amount is sent to the drive circuit 60 as a control signal.

The system controller 62 is constituted by a microcomputer, and performs centralized management of the encoder / decoder / signal processing circuit 53, the memory controller 54 and the servo circuit 61.

At the time of reproducing the mini-disc in the mini-disc device, the optical pickup 51 irradiates the mini-disc 63 as a recording medium with light and acts as a head for taking in the reflected light. Thus, the optical pickup 51 reads the RF signal (modulated compressed data) recorded on the mini-disc 63 at a rate of 1.4 Mbit / s.

[0010] The RF signal read by the optical pickup 51 is amplified by an RF amplifier 52 and then transferred to an encoder / decoder / signal processing circuit 53. The encoder / decoder / signal processing circuit 53
Is provided so as to be able to communicate with the system controller 62 in order to perform processing of the subcode, etc.
And demodulates the RF signal sent through the CDMA to convert it into compressed data, and performs a predetermined process such as error correction on the compressed data.

The memory controller 54 includes an encoder /
The compressed data sent via the decoder / signal processing circuit 53 is transferred to the shockproof memory 55 and the data compression / decompression circuit 56.

The writing and reading operations of the shock proof memory 55 are controlled by the memory controller 54, and temporarily store the compressed data output from the encoder / decoder / signal processing circuit 53.
A semiconductor memory is used as the shock proof memory 55, and for example, a 4 Mbit DRAM is appropriate. The shock proof memory 55 includes an encoder /
Absorb the difference between the transfer speed of the compressed data output from the decoder / signal processing circuit 53 and the transfer speed of the compressed data input to the data compression / decompression circuit 56, and prevent interruption of reproduction due to disturbance such as vibration. This is provided for the purpose of protecting the audio signal output.

A data compression / decompression circuit 56 as a data decompression means decompresses the data compressed by the ATRAC method and decompresses the compressed data into audio data of the original size. Data decompression processing is performed at a speed of 3 Mbit. The AD / DA converter 57 converts the audio data output from the data compression / expansion circuit 56 to analog.

On the other hand, when recording a mini-disc in the mini-disc apparatus, the AD / DA converter 57 converts the analog input audio signal into a digital signal to create audio data. The created audio data is compressed /
It is output to the expansion circuit 56.

The data compression / decompression circuit 56 has an ATRAC
The above audio data is compressed by the method, 0.3Mbi per second
Create compressed data at speed t. The compressed data is
Data compression / decompression circuit 56 to memory controller 54
Sent to

The memory controller 54 performs data compression /
The compressed data sent from the decompression circuit 56 is transferred to the shock proof memory 55 and the encoder / decoder / signal processing circuit 53. At this time, the shock proof memory 55 temporarily stores the compressed data sent from the data compression / expansion circuit 56, and transfers the compressed data output from the data compression / expansion circuit 56 to the encoder / decoder / decoder. In addition to absorbing the difference from the transfer speed of the compressed data input to the signal processing circuit 53, the audio signal output is protected to prevent interruption of recording due to disturbance such as vibration.

Encoder / decoder / signal processing circuit 53
Performs a predetermined process such as adding an error detection code to the compressed data sent from the data compression / decompression circuit 56, and then modulates the compressed data into an RF signal. The RF signal is supplied to the RF amplifier 5
After being amplified by the optical pickup 2, it is sent to the optical pickup 51, and is recorded on the mini disk 63 by the optical pickup 51.

In the above-mentioned mini disk device, compressed data transferred between the memory controller 54 and the data compression / expansion circuit 56 is processed in units called sound groups. FIG. 4 shows the format of the sound group.

The sound group is time-series data corresponding to an audio signal for one unit time, and includes a sound parameter, a word length, a scale factor, and audio spectrum data. The data amount per unit of the sound group is fixed to N bytes from the relationship between the recording capacity of the mini disc 13 and the recording time (fixed length compression). In the following description, 1
One sound group corresponds to 52 frequency spectrum data (frequency components of audio data before compression).

The sound parameter is information indicating the type of data in the sound group, and has a fixed number of bytes n1.
With the amount of data. The word length is the bit length (word length W) of each of the 52 frequency spectrum data.
L) is a data area indicating a fixed number of bytes 52 × n2
With the amount of data. The scale factor is a data area indicating an exponent part (scale factor SF) of the amplitude of each of the 52 pieces of frequency spectrum data.
It has a data amount of × n3.

The audio spectrum data is a data area indicating the mantissa part (audio spectrum data ASD) of the amplitude of each of the 52 frequency spectrum data, and the number of bytes of each audio spectrum data is determined by the word length. Although variable length, the amount of data allocated to audio spectrum data is a fixed number of bytes n4. That is,
As described above, since the total data amount of one sound group is fixed to N bytes, the data amount allocated to audio spectrum data also needs to be constant. Therefore, the total data amount of each of the audio spectrum data is actually smaller than n4, and an empty area is generated in the data area allocated to the audio spectrum data.

From the above, each audio spectrum data ASD, frequency spectrum data RAS,
The word length WL and the scale factor SF satisfy the relationship of the following equation (1).

RAS = SF × ASD / (2 ^WL−1 −1) (1) The configuration of the data compression / decompression circuit 56 is shown in FIG. When the data is compressed, the data compression / decompression circuit 56
The audio data input from the / DA converter 57 is filtered by a band filter 56a into a low band (DC to 5.5 kHz), a middle band (5.5 kHz to 11 kHz), and a high band (11 kHz).
(z to 22 KHz). afterwards,
The time / frequency axis conversion unit 56b performs MDCT (Modified Discrete Cosine Transform) on the audio data divided into the respective bands to convert the audio data into frequency spectrum data. The above-mentioned frequency spectrum data is weighted by the bit allocation / quantization unit 56c according to the bit length according to the psychological sense of human hearing. That is, a large number of bits is assigned to a frequency sensitive to the human ear, and a small number of bits is assigned to an insensitive frequency.

Conversely, when decompressing the compressed data, the data compression / decompression circuit 56 first causes the inverse quantization unit 56d to set the word length WL and scale factor of each of the compressed data received based on the above equation (1). The frequency spectrum data RAS is generated from the SF and the audio spectrum data ASD. After that, the frequency / time axis conversion unit 56e performs IMDCT (Inverse Modified Discrete Cosine Transform) on the generated frequency spectrum data RAS to perform low-frequency (DC to 5.5 KHz),
Mid range (5.5 KHz to 11 KHz) and high range (11 KHz
(KHz to 22 KHz) are generated. The time axis data of these bands is synthesized by the band synthesis filter 56f to obtain audio data.

[0025]

The above-mentioned conventional recording / reproducing apparatus and recording medium are usually formatted in consideration of only recording / reproducing of audio data. However,
The usage form of general users in recent years is not limited to simple recording and reproduction of music. For this reason, it is desirable that characters, images, and other data can be simultaneously recorded. That is, an AUX (auxiliary) data area in which each user can freely record data is required.

However, arbitrarily changing the conventional format in order to provide the AUX data area on the recording medium causes compatibility problems. In order to solve such a problem, Japanese Patent Application Laid-Open No. 9-55069 proposes to create a UTOC area dedicated to AUX data on a recording medium. In the recording method proposed in the above publication, upward compatibility with a conventional recording medium can be obtained.

However, the recording system disclosed in the above publication also has the following problems. To create a new UTOC area on the recording medium,
The original recording time is shortened by the amount of information in the UTOC area. There is a problem in obtaining complete compatibility by creating a UTOC area dedicated to AUX data (compatible when a recording medium on which AUX data is recorded by the recording method of the above publication is to be reproduced by a conventional reproducing apparatus). Sexual problems). Since the audio data and the AUX data are recorded on different tracks on the recording medium, the data does not link with each other. That is, during reproduction, the audio data and AU
In order to synchronize with the X data, it is necessary to synchronize these data by TOC management or the like, and the control unit becomes complicated.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to record AUX data on a recording medium while being completely compatible with a conventional recording / reproducing method. An object of the present invention is to provide a recording apparatus, a data recording method, and a data reproducing apparatus capable of reproducing a recording medium on which AUX data is recorded by the data recording method.

[0029]

According to a first aspect of the present invention, there is provided a data recording method for dividing main information recorded on a recording medium in time series and compressing the divided main information. And in the data recording method for recording on the recording medium for each recording unit having the first predetermined number of bits, compressing the divided main information into a second predetermined number of bits smaller than the first predetermined number of bits, Auxiliary information corresponding to the bit difference between the first predetermined number of bits and the second predetermined number of bits is added to the compressed main information for each recording unit, and the divided main information is added to the divided main information. It is characterized in that the recording unit of the first predetermined number of bits is generated with the auxiliary information to be recorded.

According to a fourth aspect of the present invention, there is provided a data recording apparatus for recording a recording unit in which auxiliary information is added to main information in a time series based on the data recording method of the first aspect. A data recording device for recording on the recording medium, a compression unit for compressing the divided main information into a second predetermined bit number range smaller than the first predetermined bit number;
Auxiliary information corresponding to a bit difference between the first predetermined number of bits and the second predetermined number of bits is added to the main information of each recording unit compressed by the compression unit, and the divided main information is And auxiliary information adding means for generating the recording unit having the first predetermined number of bits based on the auxiliary information added thereto.

According to a fifth aspect of the present invention, there is provided a data reproducing apparatus, comprising:
In a data reproducing apparatus for reproducing a recording medium in which a recording unit in which auxiliary information is added to main information is recorded in time series, auxiliary information is separated from the recording units obtained by reading the recording medium. Auxiliary information separating means; and a decompression means for receiving from the auxiliary information separating means a recording unit in which the auxiliary information has been separated and becomes only main information, and decompressing the main information. I have.

According to the first, fourth and fifth aspects, the auxiliary information adding means can add auxiliary information to the compressed main information and record the compressed main information on the recording medium. At this time, the auxiliary information includes an empty area (a difference between the first predetermined number of bits and the second predetermined number of bits) generated by compressing the main information into a second predetermined number of bits smaller than the first predetermined number of bits. (Corresponding to a bit difference), so that a new recording area for the auxiliary information is not required, and the recording time on the recording medium does not decrease.
In addition, the number of bits of the recording unit becomes the same first predetermined number of bits even after the auxiliary information is added, so that compatibility at the time of data transfer and compression or decompression of compressed data is maintained. Further, since the main information and the auxiliary information are recorded in the same recording unit in a time-division manner, at the time of reproduction, only the auxiliary information is separated from each recording unit by the auxiliary information separating means. Can be synchronized.

According to a second aspect of the present invention, in addition to the configuration of the first aspect, the recording medium is a mini-disc for recording audio data as main information by compressing the data by an ATRAC method. When compressing the audio data to be recorded, a vacant area of the auxiliary information is created in the sound group by adjusting the word length value of the sound group as the recording unit.

According to a third aspect of the present invention, in addition to the configuration of the second aspect, the auxiliary information includes control information of audio data (gain control, bass boost control, etc.) and control information (jump, pause, etc.) for a mini-disc. Etc.), at least one of image information and character information is recorded.

According to the second and third aspects of the present invention, in addition to audio data such as music, character information such as a song title can be simultaneously recorded as auxiliary information with respect to recording and reproduction of audio data on the mini-disc.

[0036]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS.

In the present embodiment, a mini disk device is exemplified as a data recording device and a data reproducing device according to the present invention. FIG. 2 shows the configuration of the mini disk device.
Shown in

The above-mentioned mini-disc device is capable of recording and reproducing audio data on an MD which is a recording medium by compressing the data, and reproducing data recorded on the MD into original audio data. Device. The mini disk device includes an optical pickup 1, an RF amplifier 2, an encoder / decoder / signal processing circuit 3, a memory controller 4,
Shock proof memory 5, multiplexer (hereinafter M
PX), data compression / decompression circuit 7, AD /
DA converter 8, feed motor 9, spindle motor 1
0, a drive circuit 11, a servo circuit 12, and a system controller 13. The components other than the MPX 6 and the data compression / decompression circuit 7 have the same configuration and operation as those of the components described in the related art, and a description thereof will be omitted.

The MPX 6 adds AUX data to the compressed data sent from the data compression / decompression circuit 7 to the memory controller 4 when recording data such as music on the MD. At this time, the data compression / decompression circuit 7
When the audio data input from the DA converter 8 is compressed to generate compressed data to be sent to the MPX 6, a sound group (recording unit) of the compressed data is configured so that the AUX data can be added.

When reproducing the data recorded on the MD into the original audio data, the MPX 6 separates the AUX data from the compressed data sent from the memory controller 4 to the data compression / decompression circuit 7. .

Here, FIG. 1 shows a format of a sound group of compressed data transmitted between the data compression / decompression circuit 7 and the memory controller 4 of the mini disk device.

The sound group is time-series data corresponding to an audio signal for one unit time, and includes a sound parameter, a word length, a scale factor, audio spectrum data, and AUX data. The data amount per unit of the sound group is fixed to N bytes as in the sound group in the conventional method. In the following description, it is assumed that one sound group corresponds to 52 frequency spectrum data (frequency components of audio data before compression).

The sound parameter is information indicating the type of data in the sound group, and is a fixed number of bytes n1.
With the amount of data. The word length is the bit length (word length W) of each of the 52 frequency spectrum data.
L) is a data area indicating a fixed number of bytes 52 × n2
With the amount of data. The scale factor is a data area indicating an exponent part (scale factor SF) of the amplitude of each of the 52 pieces of frequency spectrum data.
It has a data amount of × n3.

The audio spectrum data is a data area indicating the mantissa part (audio spectrum data ASD) of the amplitude of each of the 52 frequency spectrum data. Each audio spectrum data has a variable length because the number of bytes is determined by the word length, and the number of bytes is n4 '. At this time, the audio spectrum data of the sound group according to the present embodiment has a smaller data amount (n4 ′ <n4) than the audio spectrum data of the conventional sound group, and the resulting free space is AU.
It is used as a recording area of X data (the number of bytes n5). At this time, in the recording area of the AUX data, the data amount n5 does not need to be a constant value.

Here, in the above sound group,
Each audio spectrum data ASD, frequency spectrum data RAS, word length WL,
The scale factor SF satisfies the relationship of Expression (1) described in the related art in order to maintain compatibility with the conventional sound group.

In the sound group, the sound parameter, word length, scale factor, and audio spectrum data correspond to the compressed main information described in the appended claims, and the AUX data corresponds to the auxiliary information. . The first predetermined number of bits is N
Byte, and the second predetermined number of bits is n1 + 52 × n2 +
52 × ns + n4 ′ (<N).

The audio spectrum data is variable depending on the word length. However, in consideration of sound quality, the word length is preferably as large as possible (that is, the number of bits of the audio spectrum data is preferably large). However, even if the word length is small, it does not violate the format, so depending on the importance of the data other than the main information, the word length may be consciously set to a small value and the area for storing the AUX data may be increased. It is possible.

In the mini-disc apparatus according to the present embodiment, when data is recorded on the MD, the data compression / decompression circuit 7 converts the audio data input from the AD / DA converter 8 into the data described above. Compress according to the sound group format. At this time, in each sound group of the compressed data that has been compressed, the AUX data recording area has no AUX data recorded.

Then, the compressed data is obtained by data compression /
The data is sent from the decompression circuit 7 to the MPX 6, where the AUX data is added. Therefore, the MPX6
Has an input terminal for inputting AUX data in addition to an input terminal for inputting compressed data from the data compression / decompression circuit 7, and converts the AUX data received via this input terminal into each sound. AUX in the group
It is added to the data recording area. Thus, the data to which the AUX data has been added is sent to the memory controller 4, and thereafter, the mini disk 1 is operated by the same operation as in the related art.
4 recorded.

At this time, AUX is used for the MPX6.
The means for inputting data is not particularly limited, and is not different from a conventional device. For example, the AU
If the X data is character information such as a song name, the data can be arbitrarily input by a user from input means (such as a keyboard) built in the mini disk device or externally connected.

Next, in the above-mentioned mini disk device, M
When reproducing data (including AUX data) recorded in D, data read from the mini-disc 14 by the same operation as in the related art is sent from the memory controller 4 to the MPX 6. And the MPX6
, The AUX data is separated from the sound group. The MPX 6 has a data compression / decompression circuit 7.
In addition to the output terminal for outputting compressed data to
It has an output terminal for outputting data, and the separated AUX data is output from this output terminal.

At this time, the AU output from the MPX 6
The means for processing the X data is not particularly limited, and is no different from a conventional device. For example, A
If the UX data is character information or image information, it is sent to a display unit for displaying it, and if the AUX data is control information, it is sent to a control unit.

The compressed data after the AUX data is separated by the MPX 6 is sent to the data compression / decompression circuit 7 in the same N-byte sound group format as in the prior art, with the AUX data recording area as an empty area. Is done. The data compression / decompression circuit 7 decompresses the data and converts it into audio data in the same procedure as in the conventional case.

Further, in the mini-disc device according to the present embodiment, when the data to be reproduced does not include the AUX data,
The data transferred to X6 is sent to the data compression / decompression circuit 7 in the same format without any processing being performed in the MPX6. Since the decompression of the compressed data in the data compression / decompression circuit 7 is performed in the same procedure as in the conventional case, as described above, the mini disk device also performs the above-described data recording using the conventional data recording method. Reproduction is possible.

As is apparent from the above description, the above-mentioned mini disk device is based on the data recording method of the present invention.
In addition to being able to record and reproduce data to which UX data has been added, it is also possible to reproduce data recorded by a conventional device (by a conventional data recording method).
However, in order for the mini-disc device to achieve complete compatibility with the conventional mini-disc device, the mini-disc device must further be recorded on the mini-disc device (recorded by the data recording method of the present invention). It is necessary that the data to which the AUX data is added can be reproduced by a conventional device. The reproducing operation in such a case will be described below.

In the conventional mini-disc apparatus, A
When reproducing data to which UX data is added (that is, when reproducing the mini-disc 14 shown in FIG. 1 in the mini-disc device shown in FIG. 3), as described above,
The operation from reading data from the mini disk 14 to transferring the data to the memory controller 54 is exactly the same as that of the mini disk device shown in FIG. And
Since the MPX 6 does not exist in the mini disk device shown in FIG. 3, the compressed data including the AUX data is transferred from the memory controller 54 to the data compression / decompression circuit 56. At this time, since the data amount of each sound group of the compressed data is N bytes, which is the same as in the related art, there is no problem at the time of data transfer.

When the data compression / decompression circuit 56 decompresses the compressed data, the audio spectrum data ASD and the frequency spectrum data RAS are used for each sound group of the compressed data.
, The word length WL, and the scale factor SF satisfy the relationship of the equation (1) described in the related art, similarly to the sound group in the conventional data recording method, so that the compression can be decompressed. At this time, the number of bytes n of the recording area of the audio spectrum data ASD is
Since 4 ′ is determined by the word length WL, A
The recording area of the UX data is simply treated in the same manner as the free area in the recording area of the audio spectrum data ASD of the conventional sound group.

Therefore, the data compression / decompression circuit 5
Even if the AUX data is still included in the compressed data transferred to the AUX 6, the AUX data does not cause a malfunction of the apparatus. Data to which data has been added can be reproduced.

As described above, in the data recording method according to the present embodiment, the word length of the sound group is adjusted by adjusting the word length of the sound group when the audio data recorded on the mini-disc is compressed by the ATRAC method. A free area for AUX data can be created without changing the number of bits from the conventional one. Thus, AUX data other than audio data can be arbitrarily recorded on the mini-disc while maintaining compatibility with the conventional method.

As a result, it becomes possible to connect the apparatus according to the present invention to a personal computer or the like and record and reproduce characters and image information based on AUX data. The data format of the AUX data at this time may be any format as long as it can be recognized by a personal computer. Also, even if the apparatus according to the present invention is only for reproduction, it is possible to directly display the AUX data output as a song title or lyrics on a liquid crystal screen or the like.

At this time, since the TOC or UTOC area is not used at all as the recording area of the AUX data,
The recording time of audio data on the mini-disc does not decrease. In the mini-disc, audio data and AUX data are recorded in a time-division manner, and these data are always synchronized (TOC).
It is not necessary to synchronize again by management).

[0062]

According to the data recording method of the present invention, as described above, the divided main information is compressed into a second predetermined bit number range smaller than the first predetermined bit number, and the compressed main information is compressed. Auxiliary information corresponding to a bit difference between the first predetermined number of bits and the second predetermined number of bits is added to the main information for each recording unit, and the divided main information is added to the divided main information. In this configuration, the recording unit having the first predetermined number of bits is generated based on the auxiliary information.

According to a fourth aspect of the present invention, there is provided a data recording apparatus for compressing divided main information into a second predetermined bit number range smaller than the first predetermined bit number. Auxiliary information corresponding to the bit difference between the first predetermined number of bits and the second predetermined number of bits is added to the main information of each recording unit compressed by the means, and the divided main information is And auxiliary information adding means for generating the recording unit having the first predetermined number of bits based on the auxiliary information added to.

According to a fifth aspect of the present invention, there is provided a data reproducing apparatus comprising: an auxiliary information separating unit for separating auxiliary information from each of the recording units obtained by reading the recording medium;
The apparatus further comprises a decompression means for receiving from the auxiliary information separating means a recording unit in which the auxiliary information has been separated to become only main information, and decompressing the main information.

Therefore, according to the first, fourth and fifth aspects of the present invention, when the auxiliary information is added to the compressed main information and recorded on the recording medium, it can be used at the time of data transfer or compression of the compressed data. Alternatively, it is possible to maintain the compatibility at the time of release, do not require a new recording area for the auxiliary information, and prevent the recording time from being reduced in the recording medium.

Since the main information and the auxiliary information are recorded in the same recording unit, at the time of reproduction,
The effect that the data can be synchronized only by separating the auxiliary information from each recording unit by the auxiliary information separating means is provided.

According to the data recording method of the second aspect of the present invention, as described above, in addition to the configuration of the first aspect, the recording medium
A mini-disc for compressing audio data as main information in accordance with the ATRAC method and recording the data. When compressing audio data recorded on the mini-disc, adjusting a word length value of a sound group as the recording unit. Thus, a free area for auxiliary information is created in the sound group.

According to the data recording method of the third aspect of the present invention, as described above, in addition to the configuration of the second aspect, the auxiliary information includes control information of audio data, control information for a mini-disc, image information, and text information. At least one of the information is recorded.

Therefore, according to the configuration of the second and third aspects, in addition to the effect of the configuration of the first aspect, regarding the recording and reproduction of the audio data on the mini-disc, as auxiliary information other than the audio data such as music, etc. This provides an effect that character information such as a song name can be simultaneously recorded.

[Brief description of the drawings]

FIG. 1 illustrates one embodiment of the present invention, and is an explanatory diagram illustrating a data configuration of a sound group used for data recording.

FIG. 2, showing an embodiment of the present invention, is a block diagram illustrating a schematic configuration of a mini disk device.

FIG. 3 is a block diagram showing a schematic configuration of a conventional mini disk device.

FIG. 4 is an explanatory diagram showing a data structure of a sound group used for conventional data recording.

FIG. 5 is a functional block diagram showing a configuration of a data compression / expansion circuit of a conventional mini disk device.

[Explanation of symbols]

6 MPX (auxiliary information adding means, auxiliary information separating means) 7 Data compression / expansion circuit (compression means, decompression means) 14 Mini disk (recording medium)

Claims (5)

[Claims] In a data recording method, main information recorded on a recording medium is divided in time series, and the divided main information is compressed and recorded on the recording medium for each recording unit having a first predetermined number of bits. Compressing the divided main information into a second predetermined bit number range smaller than the first predetermined bit number, and applying the first predetermined bit number and the second predetermined bit number to the compressed main information for each recording unit. (2) A supplementary information corresponding to a bit difference from a predetermined number of bits is added, and the recording unit of the first predetermined number of bits is generated by the divided main information and the auxiliary information added thereto. Data recording method to be used. 2. The recording medium according to claim 1, wherein said recording medium is a mini-disc for compressing audio data as main information in accordance with an ATRAC method and recording said audio data. 2. The data recording method according to claim 1, wherein a free area of auxiliary information is created in the sound group by adjusting a word length value of the group. 3. The data recording according to claim 2, wherein at least one of audio data control information, control information for a mini-disc, image information, and character information is recorded as the auxiliary information. method. 4. A data recording apparatus according to claim 1, wherein a recording unit in which auxiliary information is added to main information is recorded on said recording medium in a time-series manner. Compression means for compressing the first predetermined number of bits into a second predetermined number of bits smaller than the first predetermined number of bits, and the first predetermined number of bits and the second predetermined number of bits of main information for each recording unit compressed by the compression means. Auxiliary information adding means for adding auxiliary information corresponding to a bit difference from the predetermined number of bits and generating the recording unit of the first predetermined number of bits by the divided main information and the auxiliary information added thereto A data recording device comprising: 5. A data reproducing apparatus for reproducing a recording medium on which a recording unit obtained by adding auxiliary information to main information is recorded in a time-series manner based on the data recording method according to claim 1. An auxiliary information separating unit that separates auxiliary information from each of the recording units obtained by reading the medium; and a recording unit in which auxiliary information is separated and becomes only main information from the auxiliary information separating unit. And a decompression means for decompressing the data.