JP3451624B2 - Data playback device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [0001] BACKGROUND OF THE INVENTION The present invention relates to a plurality of data files.
Data reproducing apparatus for reproducing a recording medium on which is recorded
About. [0002] 2. Description of the Related Art The applicant of the present invention has previously entered a digital
Bit compression of the audio signal
For example, a technology that records in bursts as a recording unit
For example, Japanese Patent Application No. 2-169977, Japanese Patent Application No. 2-22136
4, Japanese Patent Application No. 2-221365, Japanese Patent Application No. 2-2228
No. 21 to Japanese Patent Application No. 2-222823, each specification and drawings
And so on. [0003] This technology uses a magneto-optical disc as a recording medium.
For example, using a so-called CD-I (CD-inter
Active) and audio data files on CD-ROM XA
AD (adaptive difference) PCM
Audio data or other formats
Record digital audio data encoded by
For recording and playback. This bit-compressed digital
For audio data, a predetermined data amount is used as a recording unit,
For example, every 32 sectors,
Sectors for linking (linking in consideration of interleaving)
(Sectors) before and after, and burst (intermittent)
Data is recorded continuously. Here, for example, a so-called standard CD (core
Format (CD-DA format)
Mat) data or analog audio signals
So-called straight PC obtained by simply linear quantization
M audio data is recorded with approximately 1/4 bit compression.
Consider the case of recording and playback. This approximately 1/4 bit pressure
Playback time of the recorded disc (play time
The straight PCM data before compression, for example,
When recording data in the CD-DA format
It is almost four times. This is the standard one for smaller discs
Recording / playback time comparable to a 2cm CD
Therefore, the size of the device can be reduced. Also, record
The raw (instantaneous) bit rate is converted to the standard CD-D
By using the same format as A format,
The time required for recording and playback is approximately 1/4
So that the remaining 3/4 of the time is
Can be assigned to a lie or the like. Specifically, for example,
When recording data, make sure that the recording was successful.
Verification (verification) operation or when recording was not performed normally
Rewriting operation, etc., and during playback,
Re-reading operation when the error rate of reproduced data is high
You. As a result, for example, the mechanical part vibrates due to disturbance.
Under bad conditions where the focus or tracking may be lost
Recording and playback can be performed more reliably,
It can be applied to a mold device. [0005] Such a bit compression of approximately 1/4
To record and play back digital audio data,
Buffer memory for recording and / or reproducing compressed data
Needed. This memory stores compressed data during recording.
Is written continuously at a constant rate, and is approximately four times faster
They are read out in bursts or intermittently. This berth
The amount of data at the time of data reading is the recording unit described above.
Is a predetermined data amount, for example, 32 sectors.
A few sectors for linking are added before and after the
Spatially recorded on the disk (continue to the previous recorded part)
Is recorded. Also, during playback, burst-like
Or intermittently, the above-mentioned predetermined recording
Data amount (for example, 32 sectors + several cells for linking)
The data for linking before and after
And write the data to the buffer memory. this
Read compressed data continuously from the memory at the above constant rate.
put out. [0006] By the way, the recording data
The data compression ratio is not limited to one type.
Prepare a few types to match the data content and usage.
It is conceivable to switch the compression ratio in the same way. In this case 1
One recording medium, for example, one disk, has different compression ratios.
Multiple data files (for example, songs)
There is. As described above, for example, the pressure is
When multiple songs with different shrinkage ratios are recorded together
Means that the playback time of a song can be
Not be able to get total play time, especially
Is difficult. The present invention has been made in view of such circumstances.
Recording media such as discs with different compression ratios.
Even if multiple data files (such as songs) are mixed,
You can easily get the total time (playback time of all songs)
It is intended to provide such a data reproducing device. [0009] SUMMARY OF THE INVENTION Data reproduction according to the present invention
The device records multiple data files with different compression ratios.
Data area and the number of each data file above
Index value information to be recorded and the above data files
Address information indicating the location and compression of each of the above data files
On a recording medium having an inventory management area in which rate information is recorded
Reproducing means for reproducing the inventory management area;
Therefore, it corresponds to the number of each reproduced data file.
Index value information, the address information, and the compression ratio
Information in the data area of the recording medium based on the
Means for calculating the total time information of the data file;
The total time information calculated by the means for calculating the
With the display means for displaying, the above-described problem is solved.
Resolve. Here, as a specific example, light is applied to the recording medium.
Digitally burn discs and one data file
When one audio signal corresponds to one song, one optical
Songs with different compression ratios are mixed and recorded in the disc
At the same time, time information as address and compression rate information for each song
Information is recorded. In this case, the address
The interval information is the start time (start time) and end time of the song
(Stop time), starting from the end time
Playback as the data amount of the song by subtracting the start time
You can ask for time. Actual playback time of each song (performance
Playing time) is compressed to the above playing time as the data amount of each song.
Can be obtained by multiplying the total reduction time of each song.
By calculating the sum, the playing time of all the songs on the optical disc is calculated
Can be [0011] [Function] Time of each data file recorded on the recording medium
Information on the recording medium based on the information and compression ratio information.
File total time information, especially data obtained by decompression processing
Calculate the total playback time information for
It can be displayed on the indicating means. [0012] 1 is a block diagram of a data reproducing apparatus according to the present invention.
1 shows a schematic configuration of an optical disc recording / reproducing apparatus according to an embodiment.
FIG. 3 is a block circuit diagram. In this FIG.
There are several different bit compression ratios on recording media such as
Digit for multiple songs (multiple data files) compressed by
Audio signal is recorded. This recording signal
A predetermined recording unit (for example, 32 sectors +
Read in bursts every several sectors) and descramble
And bit through the decoder 21 for error correction decoding
Get compressed audio data. This compressed data is stored in RAM
(Random access memory) Write to memory 22
Read from the memory 22 at a constant data rate.
Data for restoring (expanding) the bit compression on the recording side.
The audio signal is reproduced through the coder 23. Here, on the optical disk 2, the above-described video
Digital audio data for multiple songs with different compression rates
Data and time information and pressure for each song (data file)
For example, if the shrinkage ratio information is in the TOC (table of contents) area
Area or a directory area. here
The time information in this case is a standard format
(Eg standard audio on so-called compact discs
Format (CD-DA format)
Address information indicating the start time and end time of the song when it is played
, And the playback time obtained by subtracting the start time from this end time
Indicates the amount of data recorded on the optical disc 2 during standard playback.
Some are represented between. The compression ratio information is defined as
Indicates the ratio of (data amount before compression) / (data amount after compression)
Information, such as standard straight PCM data
The compression ratio when compressing to 1/4 data amount is set to 4.
You. This compressed data is represented by the standard playback time.
The actual amount of data multiplied by the above compression rate
Live performances (playing songs, so-called playback)
become. Having a CPU (Central Processing Processor), etc.
The system controller 7 comprises the T
The time information and the compression rate information recorded in the OC area and the like are
Read each song (each data file) as described above
Find the actual playback time (playing time) and add these
As a result, all songs (all files) on the optical disc 2
Substantial total playing time (total playing time, total playing
Time). The calculated total playback time is the key
-Key operation on the input operation unit 8 (for example, operation of the time display key)
) Is displayed on the display unit 9 according to the
You. The TOC area and the like of the optical disc 2 include the above
Standard playback time information itself and compression for each song
Information on the actual playback time (performance time) multiplied by the rate
It may be recorded. Hereinafter, a specific configuration shown in FIG. 1 will be described in detail.
This will be described in detail. Rotated by spindle motor 1
The optical disk 2 is a recordable, for example, magneto-optical
A disk or the like is used. However, in the case of playback only,
Aluminum similar to a normal CD (compact disc)
An optical disk of a reflective film type can also be used. This
Recording on an optical disk (for example, a magneto-optical disk) 2
And / or optical head 3 for performing reproduction
For example, laser light source such as laser diode, collimator lens
Lens, objective lens, polarizing beam splitter, cylindrical
Has optical parts such as lens and light receiving part of predetermined pattern
It consists of a photo detector and the like. This optical
The head 3 is connected to the magnetic head 4 via the magneto-optical disk 2.
Is provided at a position opposite to the above. For magneto-optical disk 2
When recording data, a recording head
The magnetic head 4 is driven by the driving circuit 16 to record data.
A corresponding modulation magnetic field is applied and the optical head 3
A target track of the magneto-optical disk 2 is irradiated with a laser beam.
Thus, thermomagnetic recording is performed by a magnetic field modulation method.
The optical head 3 is used to irradiate the target
The reflected light of the light is detected, for example, by the so-called astigmatism method.
Focus error, for example, so-called push
A tracking error is detected by the pull method. Magneto-optical de
When reproducing data from the disk 2, the optical head 3 is moved upward.
When a focus error or tracking error is detected
At the same time, the polarization angle of the reflected light from the target track of the laser light
(Car rotation angle) to generate a reproduction signal. The output of the optical head 3 is supplied to an RF circuit 5
Is done. The RF circuit 5 outputs the signal from the output of the optical head 3
Extract the focus error signal and tracking error signal.
And supplies the reproduced signal to the servo control circuit 6.
Is supplied to a decoder 21 of a reproduction system to be described later.
You. The servo control circuit 6 includes, for example, a focus sensor.
Control circuit, tracking servo control circuit, spindle
Motor servo control circuit, thread servo control circuit, etc.
It is composed of The focus servo control circuit is
Optical head so that the focus error signal becomes zero
The focus control of the optical system 3 is performed. Also the above truck
The tracking servo control circuit generates the tracking error signal
Tracking of the optical system of the optical head 3 so that it becomes zero
Perform control. Furthermore, the spindle motor servo control circuit
The path rotates the magneto-optical disk 2 at a predetermined rotational speed (for example, a constant rotational speed).
Linear motor) to control the spindle motor 1 to rotate.
I will. In addition, the above-described thread servo control circuit is
Of the magneto-optical disk 2 specified by the
Move the optical head 3 and the magnetic head 4 to the target track position.
Move. Servo control circuit that performs such various control operations
The path 6 controls the operation of each part controlled by the servo control circuit 6.
Information indicating the operation status is supplied to the system controller 7.
I have. Key input operation to the system controller 7
The unit 8 and the display unit 9 are connected. This system controller
The roller 7 is controlled by operation input information from the key input operation unit 8.
Controls the recording and playback systems in the specified operation mode.
U. The system controller 7 controls the magneto-optical disk 2
Header data and subcode Q data
Address information (time
Information), the optical head 3 and the magnetic head 4
Recording position and playback position on the above-mentioned recording track that is racing
Manage the location. The display unit 9 displays the recording position or the reproduction position.
Location information and information on the function selected by the key operation described above.
Are displayed as necessary. Here, Table 1 shows the magneto-optical
Read on a recordable and reproducible disc like disc 2
So-called subcode Q channel in the
Contents recorded as channel signals (recording format)
Is shown. [Table 1] In Table 1, P in the item of P / R is:
Recorded in advance as a so-called mechanical pit so that it cannot be rewritten
Indicates the formed pre-master part, R is recordable
Parts are shown. The above time related to the embodiment of the present invention
The information and compression ratio information are stored in the TOC for the user (so-called UT
In the OC) area, the index is in the range of N + 1 to 99
Be recorded. Where N is the so-called BCD (Binary Decimal)
Numerical value) takes any value from 00 to 98. This
Of the U-TOC (TOC for users)
It is possible to write the above compression ratio information in
Table 2 shows one specific example. [Table 2] In Table 2, the so-called "zero-by"
Bit 7 (the most significant bit) of each song is an overlay for each song
Used as a flag to indicate write (rewrite) protection
When this bit 7 is "0", writing is performed.
Prohibition and "1" are defined as writing permission.
Bits 0-2 of this so-called "zero-byte" (lower side)
(3 bits) indicates information on the compression ratio.
That is, bit 2 represents the sampling frequency fs,
Bit 1 is a bit compression algorithm, bit 0 is stereo
/ Monaural respectively. About bit 2
Is the standard CD-DA format when "0"
Sampling frequency of 44.1 kHz (or
Formats such as so-called CD-I and CD-ROM / XA
37.8 kHz, which is the standard sampling frequency of
When "1", the frequency is half that frequency. This sump
Ring data shall be quantized by 16 bits, and
The compression algorithm of bit 1 is 1/4 when “0”.
Compressed to about 4 bits, when "1" is 1/2, about 8 bits
Stipulates that it be compressed. Bit 0 is “0”
Stereo and “1” indicate monaural.
You. From the values of these bits 2 to 0, as shown in Table 3,
The compression ratio in each case is determined. [Table 3]As apparent from Table 3, for example,
G2 = “0” sampling frequency is standard (44.1k
Hz or 37.8 kHz), and bit 1 = about 8 bits of "1"
Bit 0 = "0"
In the case of stereo, the compression ratio is the smallest and is “2”. Ma
Conversely, the sampling frequency of bit 2 = "1" is half
(22.05 kHz or 18.9 kHz), bit 1 =
Using an algorithm that compresses to about 4 bits of “0”,
When the bit 0 = “1” monaural, the compression ratio is the highest
It becomes “16”. For other combinations of each bit value, the compression ratio
Is "4" or "8". Here, the U-TOC (U
Table 4 shows a specific example of the recorded contents in the
You. [Table 4] Table 4 shows that the magneto-optical disk 2 has four songs.
Shows a specific example of the recorded contents of the U-TOC at the time when
The start time (start time)
Time) and end time (stop time)
You. Whether the index is time information corresponding to B2 and B3
3 minutes 43 seconds 28 frames (standard playback time)
It can be seen that recording has been performed up to the address position of (h).
R> Track, index, start time and
As shown in Table 1 above, each piece of information on the end time is
Directly recorded and played back as the Q channel signal of the code.
It is. The compression ratio information is based on the so-called “zero-bye”.
As shown in Table 3 above, based on the values of bits 0 to 2 of
You can ask. Here, the standard playback time for each song
Subtracts the start time from the end time of each song
The compression ratio for each song is calculated as
4, 8 for the second and third songs, 8 for the third song, 4 for the fourth song
Therefore, multiply each of these compression ratios
The actual playback time (playing time, playing
Time). Such an operation is performed by the system
Performed by Troller 7 and the actual playback time for each song
By taking the total of the total playback time (playing time)
Obtainable. In the example of Table 4, 15 minutes 54 seconds 2 frames
(Block).
It is displayed on the display unit 9. Actual playback time like this (playing
Table 5 shows a generalized calculation of the time). [Table 5]In Table 5, the actual reproduction of one song
The time Tp is the end time Te represented by the standard reproduction time.
Is subtracted from the start time Ts by the compression ratio k of the song.
By multiplication, it is obtained as Tp = k (Te-Ts)
be able to. Next, the recording system of this disk recording / reproducing apparatus
explain about. Analog audio from input terminal 10
E Input signal A_INA / D through the low-pass filter 11
It is supplied to a converter 12. The A / D converter 12 is
Analog audio input signal A_INQuantized and obtained
The digital audio signal is, for example, AD (adaptive difference)
Encoder 13 for high efficiency encoding processing such as PCM
Supplied. Also, external digital audio signals
Signal to the digital input interface circuit (shown
May be supplied to the encoder 13 via the
No. The digital audio input to the encoder 13
Io PCM signals are not subjected to compression processing or the like.
Straight PCM data.
CD (Compact Disc) Format (CD
−DA format), the sampling frequency is
PCM with 44.1 kHz and 16-bit quantization bit rate
Data. This input audio PCM data
Is transmitted by the encoder 13, for example, as described above.
Pulling frequency, bit compression algorithm, and stereo
1/2 to 1/16 of the video depending on the combination of
High-efficiency compression encoding processing
You. In the following explanation, it is compressed to approximately 1/4 bit rate
(When the above-mentioned compression ratio is 4),
In addition, to bit rates of 1/2, 1/8, 1/16, etc.
The basic operation is the same in the case of compression. Next, the memory 14 writes data and
The reading is controlled by the system controller 7, and the
Bit compressed data supplied from the encoder 13
And record it on the disk as needed.
Used as a buffer memory. Ie example
For example, in the data compression mode with a compression ratio of 4,
Standard CD-DA format data transfer rate (bit
Constant rate reduced to approximately 1/4 of
Is continuously written into the memory 14.
When recording this compressed data on the magneto-optical disk 2,
Same disc times as the standard CD-DA format
Bar at the same data transfer speed under the transfer speed (constant linear speed)
It is recorded as a strike or discretely. That is,
The actual recording time of the signal at the time of loading
1/4 each and the remaining 3/4 of the time
There is no pause. However, on the magneto-optical disk 2,
Is the next recording after the area recorded just before the pause
Is performed, and continuous recording is performed on the medium surface.
I have to. Thereby, for example, a standard CD-DA
Recording of the same recording density and storage pattern as the format
Will be For this reason, the standard
Bits corresponding to the data transfer speed of the CD-DA format
The compressed data is read out in bursts at a rate,
The read compressed data is interleaved and
Error correction encoding processing, EFM modulation processing, etc.
Is supplied to the encoder 15. Here, the memory 14
The data string supplied to the encoder 15 has a predetermined
One cluster consisting of several sectors (for example, 32 sectors)
It is a unit that is continuously recorded in one recording, and this is
Code processing, the amount of data for one cluster is reduced.
The amount of data with several sectors for raster connection added
You. This sector for cluster connection is
The interleave length is set longer than the interleave length.
Will not affect data in other clusters
I have to. About the details of this cluster unit recording
Will be described later with reference to FIG. The encoder 15 reads the data from the memory 14 as described above.
As described above, recording data supplied in bursts
Encoding for error correction (parity addition and input
(Tarley processing), EFM encoding processing, and the like. Also,
Addition of synchronization pattern and so-called sub-coding part
Simultaneously, the U-TOC (TOC for user) area
In the Q channel of the sub-coding part in
-Time information and compression rate information as described with Table 4 etc.
Be recorded. The encoding process by the encoder 15 is performed.
The recorded data is supplied to the magnetic head drive circuit 16.
It is. The magnetic head drive circuit 16 includes a magnetic head 4
Connected, and modulates the modulated magnetic field according to the recording data
Driving the magnetic head 4 so as to apply it to the magnetic disk 2
You. The system controller 7 has a memory
14 and the memory control as described above.
Read from the memory 14 in burst by the memory control of
The above recorded data is recorded on the recording track of the magneto-optical disk 2.
The recording position is controlled so that recording is continuously performed on the recording medium. This
The control of the recording position is performed by the system controller 7.
The recording data read in bursts from the memory 14
The recording position of the magneto-optical disk 2
Control signal for designating the recording position on the servo control circuit 6
Is performed by supplying the Next, a reproducing system of the disk recording / reproducing apparatus will be described.
Will be described. This reproduction system is based on the recording system described above.
Continuously recorded on the recording tracks of the magneto-optical disk 2
Optical head for reproducing recorded data
3, the recording track on the magneto-optical disk 2 is
Recording from the magneto-optical disk 2 by tracing with
The signal is read. Here, the magneto-optical disk 2 is
The same rotation speed as the standard CD-DA format (line
(CD-DA format)
Burst (discrete) at the same data transfer rate as the mat
Recorded signal is read and binarized by RF amplifier circuit 5
And supplied to the decoder 21. The decoder 21 operates in the above-described recording system.
And the RF circuit 5
Deinterleaving of the binarized playback output
Decoding and EFM demodulation for processing and error correction
Processing, and compresses the compressed data having the compression ratio of 4,
Same data transfer speed as standard CD-DA format
Output in bursts at degrees. In addition, the U-TOC (user
TOC) area subcode Q channel signal
Based on the above time information (start time, end time)
And bits 0 to 2 of the so-called "zero-byte"
, The compression ratio information is obtained. This decoder 21
The obtained reproduction data is supplied to the memory 22 and
Code information and the like are supplied to the system controller 7. The memory 22 writes and reads data.
Is controlled by the system controller 7, and
Same as the above standard CD-DA format
Playback data supplied in bursts at the data transfer rate
Written. The memory 22 stores the burst
The above-mentioned reproduction data written in a fixed bit rate
Abbreviation of the standard CD-DA format
The data is continuously read at a data transfer rate of 1/4. The system controller 7 provides such a
Memory for writing / reading the reproduction data to / from the memory 22
Control is performed, and the memory 22 is controlled by this memory control.
The reproduced data written in bursts from the
Play back from the recording track of disk 2
Control the raw position. This playback position control is controlled by the system
Burst read from memory 22 by controller 7
By controlling the reproduction position of the reproduced data output,
Control for specifying a playback position on a recording track of the disk 2
This is performed by supplying signals to the servo control circuit 6.
You. From the memory 22, a conversion of approximately 1/4 of the above standard
Playback data read continuously at the transmission speed (bit rate)
The compressed data obtained as data is supplied to the decoder 23.
Is done. The decoder 23 is an encoder of the recording system.
13 corresponding to, for example, 1/4 compressed data
Is expanded by four times (bit expansion), for example.
6-bit digital audio data is reproduced. This
The digital audio data from the decoder 23 of
It is supplied to the D / A converter 24. The D / A converter 24 is supplied from the decoder 23.
Digital audio data supplied into analog signals
After conversion, the signal is output to the output terminal 26 through the low-pass filter 25.
Analog audio output signal A_OUTIs output. By the way, such a disk recording / reproducing apparatus
The magneto-optical disk 2 used for the installation has a stereo audio
The capacity that can record 60 minutes or more and about 74 minutes with an e-signal
It is desirable that the data compression ratio be 4
, About 130 Mbytes are required.
In addition, a portable or pocket-sized record and / or
Or, in order to configure a reproducing apparatus, the outer diameter of the disc is 8c.
m or smaller diameter discs
Good. In addition, track pitch and linear velocity
Has a track pitch of 1.6 μm and a linear velocity of 1.
It is desired to be 2 to 1.4 m / s. These conditions
For example, a disk satisfying
4mm, data recording area 61mm outside diameter, data recording
The inner diameter of the area is 32 mm, the inner diameter of the lead-in area is 30 mm,
The center hole diameter may be 10 mm. This disk
In a 70mm x 74mm disk caddy
If you supply it to the market,
Recording / reproduction to / from the disc is possible with the recording / reproduction device
Becomes 72 minutes in the data compression mode with a compression ratio of 4
Of a disc to enable recording and playback for about 76 minutes
As the range of the inner diameter and outer diameter of the data recording area,
From the outer diameter of 60 mm to 62 mm when the inner diameter is 32 mm,
Outer diameter range from 71mm to 73mm when the diameter is 50mm
Can be set appropriately. Next, the disk recording and reproduction as described above is performed.
Further details on the basic recording and playback operations
This will be described in detail. First, the recording data (read from the memory 14)
The output data) has a fixed number (for example, 32) of sectors.
(Or blocks).
Several sectors for cluster connection are arranged between rasters
It is in the form that was. Specifically, as shown in FIG.
Cluster C consists of 32 sectors (blocks) B0-B31
And each of these clusters C has four
Sectors L1 to L4 for connection (for linking) are
Connected to the raster. Where one cluster, example
For example, the k-th cluster C_kIf you want to record
Raster C_k32 sectors B0-B31 as well as the
3 sectors and 1 sector behind are connecting sectors, ie
Cluster C_k-1Two sections for run-in blocks on the side
Data L2, L3 and one sector L4 for sub data, and class
TA C_{k + 1}One sector L1 for run-out block on the side
And recording in units of 36 sectors in total.
I have to. At this time, the recording data for these 36 sectors is
The data is sent from the memory 14 to the encoder 15 and this
The interleave processing is performed by the encoder 15.
And a maximum distance of 108 frames (corresponding to about 1.1 sectors).
The rearrangement is performed, but the cluster C_kDay in
For the data, the range of the linking sectors L1 to L4
Within the other cluster C_k-1And C_{k + 1}
Has no effect on For sectors L1 to L3,
For example, dummy data such as 0 is arranged, and an auxiliary
Sub data is allocated, and
Adverse effects on the original data can be avoided. here,
The main data sectors B0 to B31 are shown in FIG.
So, 0000 in an 8-bit binary number (2 hexadecimal digits)
Sector numbers from 0000 (00H) to 0001 1111 (1FH)
0010 is attached to the sector L1 of the linking part.
0000 (20H), 0011 1101 (3DH) to 0 for L2 to L4
011 1111 (3FH) sector numbers are assigned respectively.
You. Also, as the cluster, a linking sector is used.
, For example, 36 sectors may be defined as one cluster. Such a linking sector is a berth sector.
Necessary for easy recording and overwrite recording.
It is required, but all tracks are continuously recorded on the disk.
When recording tracks, use commercially available playback-only software.
It is unnecessary when creating a disc, etc.
As shown in B of FIG.
It may be connected (without linking sector)
No. In this case, both the data cluster and the recording cluster
32 sectors. Here, actual recording on the magneto-optical disk 2 is performed.
Per physical sector or cluster
Are shown in Table 6. Table 6 shows that
The values calculated in accordance with B in FIG. 3 are shown, as described above.
When adding a linking sector like this,
Crab becomes longer. It should be noted that the definition of the compression ratio may vary.
And the value will change slightly. [Table 6] The recording in such a cluster unit is performed.
Interleaving with other clusters
Eliminates the need to consider mutual interference
It is greatly simplified. Also out of focus, track
Recording data during recording due to misalignment or other malfunction.
If the data could not be recorded normally, the above cluster unit
For re-recording and effective data reading during playback
If not, you can re-read in cluster units
You. Incidentally, one sector (block) is 235.
It consists of 2 bytes, 12 bytes for synchronization,
23 for 4 bytes for data and data D0001 to D2336
36 bytes are arranged in this order. This sector structure
12 bytes for synchronization in the structure (block structure)
Means that the first byte is 00H (H indicates a hexadecimal number)
10 bytes of FFH follow, the last byte is 00H
Has become. The next 4-byte header is one byte each.
After the minutes, seconds, and the address part of the block,
It consists of one byte for code information. This mode information
Is mainly for indicating the mode of the CD-ROM.
Yes, the internal structure of the sector shown in FIG.
This corresponds to the mode 2 of the format. CD-I
This is a standard using the mode 2 of FIG. In the specific example shown in FIG.
Indicates the format for recording data
From the beginning of the 2336-byte area,
Da, 18 groups of sound groups of 128 bytes each
SG01 to SG18, a space area of 20 bytes, and
They are arranged in the order of the 4-byte reserve area. 8 above
The byte subheader contains a 1-byte file number,
The channel number, submode, and data type are repeated twice.
It was placed back. By the way, data of such a sector structure is
Is recorded on the disk by the encoder 15.
Encoding processing including parity addition and interleave processing
Processing is performed, and EFM (8-14 modulation) processing is performed.
Recording is performed in a recording format as shown in FIG. In FIG. 4, one block (one section)
98 frames from the first frame to the 98th frame
One frame is composed of a channel clock period T
588 times (588T), 24T (+ contact) in one frame
3T) frame synchronization pattern portion, 14T
(+ Connection bit 3T) subcode part and 544T
Data (audio data and parity data) part
Is provided. The data part of 544T is 12 bytes
(12 symbols) audio data, 4 bytes Paris
Data, 12 bytes of audio data, and 4 bytes
The parity data of the unit is so-called EFM modulated
And the audio data in one frame is 24 bytes
(Ie, one word of audio sample data is 16 words)
12 words). The above sub
In the code part, 8-bit subcode data is EFM modulated
It is divided into 98 frames.
Thus, each bit constitutes eight subcode channels P to W.
Has formed. Where the subcodes of the first and second frames
The part is out of rule of EFM modulation (out-of-rule).
Lock synchronization pattern S_0,S₁And each sub-
The channels P to W are from the third frame to the 98th frame
Up to 96 bits each. The audio data is interleaved.
Recorded during playback, but it is deinterleaved during playback.
Of the data array that has been processed
Odata Instead of this audio data,
General CD-I data and the like can be recorded. Incidentally, the disk recording / reproducing apparatus shown in FIG.
In the configuration, the system controller 7 operates as shown in FIG.
Thus, the write pointer W of the memory 14 is
Increments continuously at a rate corresponding to the bit rate of the
And write continuously and stored in this memory 14
The unread data amount of the compressed data is a predetermined amount M_Kthat's all
, The read pointer R of the memory 14 is set to the standard
Burst at a transfer rate according to the standard CD-DA format
Incremented by a predetermined unit (for example, 32
Memory control is performed so as to read out each time. Follow
In the memory 14, the unread data may be destroyed.
The amount of data that can be written, that is, the recordable capacity,
Predetermined amount (M_T-M_K) Will be prevented from falling below
Become. Here, the data is read from the memory 14 in a burst manner.
The output recording data is transmitted by the system controller 7.
The recording position on the recording track of the magneto-optical disk 2 is controlled.
In this way, on the recording track of the magneto-optical disk 2,
It can be recorded in a continuous state. And above
As shown in FIG.
Area is secured, so track disturbances
System controller 7 detects that
The recording operation on the magneto-optical disk 2 is interrupted
The input data is also stored in the recordable area of the predetermined amount or more.
Can continue to be written, and during that time
Input data on the recording track of the magneto-optical disk 2.
Data can be recorded in a continuous state. Next, in the disk recording / reproducing apparatus shown in FIG.
In the reproducing system, the system controller 7 is configured as shown in FIG.
Thus, the write pointer W of the memory 22 is
-Increment at transfer rate according to DA format
And write in bursts, and read memory 22
Pointer R according to the bit rate of the compressed data.
The data is read out by continuously incrementing at the speed
Pointer W catches up with the read pointer R (the
Stop writing when the
The unread data amount stored in the memory 22 is a predetermined amount.
Quantity M_LMemory control to write
Do. Therefore, the predetermined amount M is always stored in the memory 22._LNot more
While securing the data read area of the read data amount,
Raw data can be read continuously from the memory 22.
Wear. The data written to the memory 22 in a burst is
The raw data is stored in the magneto-optical
By controlling the playback position on the recording track of disc 2
That is, a continuous state on the recording track of the magneto-optical disk 2
Can be played in a state. Moreover, as noted above,
The predetermined amount M is always_LThe above data read area is
Track jump due to disturbance etc.
The system controller 7 detects that the
When the reproducing operation for the magnetic disk 2 is interrupted,
The predetermined amount M_LFrom the above data read area,
Data and continue output of analog audio signal
During which the recovery operation can be performed.
You. By the way, the small-diameter magneto-optical
A system that records compressed audio data on disk 2
In the system, the optical disk 2 before recording is
Woblin for cutting pre-grooves
Record absolute time information as
(ATIP: Absolute Time Imp Groove)
It is considered, how to put time information in this ATIP
And how to put time information in the so-called header time part, etc.
Several formats have been proposed. But
In the small-diameter disk system described above,
Address on the disk or the address of the sector
Even if you put in time (minute, second, frame) like CD
Not only does it have little benefit, but the linking described above
The time required for correction and display
Is not preferred. So, for example,
The compression ratio is determined as follows, and as shown in FIG.
When assigning each sector number, the audio
The data part for reproducing the signal has the above sector number.
8-bit binary number (2 hexadecimal digits), 0000 0000
(00H) to 0001 1111 (1FH) recorded only in sectors
Is done. In that sense, the re-use of the aluminum reflective film
Recording is possible using a magneto-optical recording medium film, etc., even for raw discs.
Only the sector data with the same sector number
Since the data is sent to the memory 22, the
Processing for display and processing for total time display
Is performed, the processing can be shared. The actual performance
The display of the time is performed by detecting the above-mentioned compression ratio information,
The product sum with the number of sectors and the number of clusters is calculated and obtained.
What is necessary is just to display it. The present invention is not limited to the above embodiment.
For example, only an optical disk recording / reproducing device
Instead, the present invention can be applied to a playback-only device. Also,
The time information recorded on the recording medium includes the start time and
Playback time and actual performance time are not limited to the end time.
It may be written in the U-TOC area or the like.
Also, the time information and the compression ratio information include the Q code of the subcode.
In addition to using the channel signal, for example, in one sector in FIG.
Write to header part and sub header part etc.
Other than the U-TOC in the lead-in area of the disc
Or the like. [0051] According to the data reproducing apparatus of the present invention,
Data recorded with multiple data files with different compression ratios
Data area and the number corresponding to the data file number.
Indicates the index value information and the recording position of each data file.
Address information and compression rate information for each of the above data files
The above-mentioned inventory tube of a recording medium having a recorded inventory management area
Playback of the data area, and
The corresponding index value information and the address information
The data area of the recording medium is determined based on the compression ratio information.
Total time information of all data files in the area, especially
Total playback time information for the data obtained
It can be calculated and displayed on the display means. Here, an optical disk is used as the recording medium.
Use the digital audio signal 1 in the data file
When corresponding to music pieces, the compression ratio is stored in one optical disc.
Of different songs are recorded together, and an address is assigned to each song.
All time information and compression rate information are recorded. This place
If the time information as an address is
Information indicating the start time) and the end time (stop time).
By subtracting the start time from the end time,
The reproduction time as the data amount can be obtained. each
The actual playback time (playing time) of a song is based on the data volume of each song and
Can be obtained by multiplying the above playback time by the compression ratio.
By calculating the total playing time of each song,
Of all songs can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block circuit diagram showing a configuration example of a disk recording / reproducing apparatus as one embodiment of a data reproducing apparatus according to the present invention. FIG. 2 is a diagram showing a format of a cluster structure serving as a recording unit on a recording medium. FIG. 3 is a diagram showing the contents of each sector of the cluster structure of FIG. 2; FIG. 4 is a diagram showing a format of a frame and a sector (block) in the standard of a so-called CD (compact disk). FIG. 5 is a diagram showing a state of a memory whose memory is controlled in a recording system of the disk recording / reproducing apparatus of the embodiment. FIG. 6 is a diagram showing a state of a memory whose memory is controlled in a reproducing system of the disk recording / reproducing apparatus of the embodiment. [Explanation of symbols] 2 ... Magneto-optical disk 3 ... Optical head 7 ... System controller 8 ... Key input operation unit 9 ... Display unit 13 ... ... Data compression encoders 14, 22... Memory 15... Encoder 16... Magnetic head drive circuit 21... Decoder 23. decoder

Claims (1)

(57) [Claims] [Claim 1] A data area in which a plurality of data files having different compression rates are recorded, and a number of each data file
Reproduction means for reproducing the index management area of the recording medium having the index value information, the address information indicating the recording position of each data file, and the compression rate information of each data file. The number of each data file reproduced by the reproduction means
Means for calculating total time information of all data files in the data area of the recording medium based on the index value information, the address information, and the compression ratio information corresponding to the number, and calculating the total time information. Display means for displaying the total time information calculated by the means.