JP2000040348A - Reproducer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make pieces of specified music of disks specified by a user to be continuously reproduced from leading parts instantly and without interrupting information even when the exchanging of disks is needed as to many pieces of music while using a memory having a small capacity. SOLUTION: At the time of initializing a system such as the time of supplying a power source to the system, data of leading parts of pieces of music are read out from respective disks and the data are compressed in a data compressing circuit 41 to be stored in a leading part memory in a memory block 12. After initialization, when a certain music of a certain disk is being reproduced, in the case a user requests the reproducing of a certain music of a different disk, at first, the leading part data posterior to the compression of the specified music of the disk specified by the user are read out from the leading part memory and the data are expanded by a data expanding circuit 44 to be outputted. In parallel with this, the disk specified by the user is loaded on a player box and data following the leading part data of the music specified by the user are read out to be written in the main memory in the memory block 12 and the following part data are read out from the main memory after the leading part data posterior to the compression are all read out from the leading part memory.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention can store a plurality of recording media such as an MD (mini-disc) and a CD (compact disc) on which information such as music is recorded. And a playback device such as an MD changer system or a CD changer system, which can select and play back.

[0002]

2. Description of the Related Art An MD changer system and a C-changer system capable of accommodating a plurality of disks such as MDs and CDs and selecting and reproducing an arbitrary disk from the plurality of disks.
Disc changer systems such as the D changer system have been put to practical use.

Further, a method of improving operability by sequentially writing digital data read from a disk on which music is recorded as digital data to a memory such as a RAM, and reading and outputting the data from the memory has been considered. I have.

[0004]

However, in the above-described disc changer system, when a disc is exchanged at the request of a user, the disc is actually exchanged until the disc designated by the user is reproduced.
It takes a long time of up to about 10 seconds, during which time the silent state continues, giving the user discomfort.

Therefore, in such a disc changer system, even when the disc needs to be replaced, a method in which the disc specified by the user is immediately and continuously reproduced from the head without any interruption of sound can be considered. ing.

In this method, a memory (hereinafter referred to as a head memory) for storing head data of a disk separately from a memory (hereinafter referred to as a main memory) for sequentially writing and sequentially reading data read from the disk as described above. Is provided in advance, and the head data of each disc is stored in the head memory in advance, and when a user-specified disc is reproduced, first, the user designates the data specified by the user from the head memory. Read and output the data at the beginning of the disk, replace the disk,
Reads the data after the head data from the disk specified by the user and writes it to the main memory, reads all the head data from the head memory, and then reads and outputs the data after the head data from the main memory It is.

However, the main memory and the head memory may be separate memories, or may be separate areas of one memory.

According to the above-mentioned method, even when the disk needs to be replaced, the disk specified by the user is immediately and continuously reproduced from the head without interruption.

In this case, for example, in a vehicle-mounted disc changer system, when a user is playing a certain disc while driving a car and wants to know the contents of a different disc, and specifies a different disc, In order to cope with this, data of the head of the disc itself, for example, data of the head of the first tune, so-called intro part, may be stored in the head memory as the head data.

However, in the case of an MD or CD, several songs are often recorded, and a user may request reproduction by designating a disc and a song at the same time, such as a song number of a certain disc. Many. Even in such a case, in order for the specified music on the disk specified by the user to be immediately and continuously reproduced from the head without any interruption of the sound, the data of all the disks on all the disks must be used as the head data. It is necessary to store the data at the beginning of a song or many songs in the beginning memory.

FIG. 5 shows an example of a possible memory configuration when the head data of all songs or many songs on all disks is stored in the head memory.
This is a case where five disks 1a to 1e can be stored in the system, and the head data of a maximum of x songs of each of the disks 1a to 1e can be stored in the head memory.

In this example, the entire memory is defined as a memory block 12, one main memory 12M having a memory address from 00000 to 7FFFF, and 8 blocks each.
X head memories 12S1, 12S2... 12Sx having memory addresses from 0000 to FFFFF;
The selector 51 selects one of the head memories 12S1 to 12Sx.

The main memory 12M stores 00000 to 0F
The TOC (Table O) described later in the address area up to the FFF
f Contents) TOM memory area 12M where information is stored
1 and a disk memory area 12M2 in the address area from 10000 to 4FFFF in which data after the head data is stored.

The disk memory area 12M2 stores the memory data input 2 under the control of the system controller.
1 is stored while the last input address in the past is incremented. As a result, when the input address reaches 4FFFF, the next lower address is returned to the address 10000.
, A so-called ring buffer configuration.

In the course of the accumulation, the memory data input 21
When the input address reaches the output address of the memory data output 22, the accumulation of data in the disk memory area 12M2 is stopped. Then, the disk memory area 1
From the area 12M3 where data in 2M2 is stored,
The memory data output 22 is read while incrementing the output address from the lower order.

T stored in TOC memory area 12M1
The OC information is disc management information such as the title, time, and address of a song recorded on each of the discs 1a to 1e. Reading from the disks 1a to 1e, the TOC memory area 12M1
And used for disk access by the system controller.

When the system is initialized such as when the system is powered on, the disc 1a is first mounted on the player box, and the TOC information recorded on the innermost portion of the disc 1a and the first track are read from the disc 1a. To the x-th tune, the TOC information is written in the TOC memory area 12M1 in the main memory 12M, and the selector 51 is used to read the head memory 12S1 to 12S1.
By sequentially selecting 12Sx, the leading data D
a1 to Dax are sequentially stored in the head memories 12S1 to 12Sx.
It is stored in the address area of 80000 to 8FFFF corresponding to the medium disk 1a.

Similarly, disks 1b, 1c, 1d, 1e
To the player box,
b, 1c, 1d, and 1e, the respective TOC information and the head data Db of each of the first to x-th songs.
1 to Dbx, Dc1 to Dcx, Dd1 to Ddx, De1
To Dex, the TOC information is written to the TOC memory area 12M1, and the selectors 51 sequentially select the head memories 12S1 to 12Sx, so that the head data Db1 to Dbx, Dc1 to Dcx, D
d1 to Ddx and De1 to Dex are sequentially stored in the head memory 1
Disks 1b, 1c, 1d, 1e in 2S1 to 12Sx
90000-9FFFF, A0000-AF corresponding to
FFF, B0000-BFFFF, C0000-CFF
It is stored in the address area of the FF.

After such initialization, for example, the disk 1
a while playing a song with a
When the reproduction of the second song is requested, first, the selector 51 selects the head memory 12S2 and sets the output address of the memory data output 22 to the address 9
0000 and 9000 in the head memory 12S2.
From the address area of 0 to 9FFFF, the head data Db2 of the second tune of the disk 1b stored therein is read and output.

Therefore, immediately after the music selection operation by the user, the head of the second music on the disc 1b specified by the user is reproduced.

At the same time, the disc 1a is removed from the player box and returned to the original position of the disc box, then the disc box is moved, and then the disc 1b designated by the user is loaded from the disc box into the player box. I do.

Thereafter, at the time of system initialization, T
Based on the TOC information stored in the OC memory area 12M1, the head data Db of the second song on the disk 1b
Access to the address location following 2 to disc 1b
, The data after the head data Db2 of the second music is read, and the data after the read head data Db2 is used as the memory data input 21 in the disk memory area 12M2 in the main memory 12M and the head address 10b.
Save from 000.

After the music selection operation by the user, the head data Db2
The time until the subsequent data is started to be stored in the disk memory area 12M2 is about 7 to 11 seconds, and the leading data is set to about 14 seconds as the reproduction output time. The head part data Db2 has been read from the memory 12S2.

Then, from the time of the music selection operation by the user, about 1
Four seconds later, when all the head data Db2 is read, the output address of the memory data output 22 is changed to the address 9FF.
From the FF, the data is changed to the head address 10000 of the disk memory area 12M2, and the data after the head data Db2 of the second music on the disk 1b is read and output.

Therefore, the disk 1 specified by the user
From the beginning of the second song of b to the subsequent part,
Sound is played continuously without interruption. Subsequent processing is the same as that of the system in which the head data is not stored in the memory.

As described above, according to the above-described configuration and operation, even when the disk needs to be replaced, the specified music on the disk specified by the user can be continuously played from the head immediately without interruption. And played.

However, for this purpose, it is necessary to store the head data of all songs or many songs on all disks in the head memory, and a large number of memories or large-capacity memories are required as the head memory. As a result, the cost of the system is increased, and the size of the system is increased because the substrate area is increased.

Therefore, according to the present invention, by storing the head data in the memory in advance, even if the disk needs to be replaced, the specified music on the disk specified by the user can be played immediately from the head. In a playback device such as a disc changer system in which playback is continuously performed without interruption, a small number or capacity of memory can store the leading data of a large number of songs or information other than songs, and a small number or capacity of The memory enables such instantaneous continuous reproduction of a large number of songs or information other than songs.

[0029]

According to the present invention, in a reproducing apparatus capable of storing a plurality of recording media and mounting a selected recording medium at a predetermined position and reproducing the data, data read from the recording medium is sequentially read. A main storage unit to be written and a sub-storage unit for storing head data of each recording medium are provided, and at the time of device initialization, the head data read from each recording medium is compressed by a data compression circuit, and The data is stored in the secondary storage means, and at the time of reproduction, the corresponding compressed head data is read from the secondary storage means, decompressed and output by the data decompression circuit, and the data after the head data is read from the corresponding recording medium. By writing to the main storage means and reading and outputting from the main storage means, the requested recording medium is reproduced.

In the reproducing apparatus of the present invention configured as described above, at the time of initialization of the apparatus, the head data read from the recording medium is compressed by the data compression circuit and stored in the secondary storage means. Since the head data after compression is read out from the storage means and output after being decompressed by the data decompression circuit, the head data read from the recording medium is not data-compressed even with the head data for the same time as the reproduction output time. As compared with the case, the memory capacity required to store one head data is reduced.

Therefore, the head data of a large number of music pieces or information other than music pieces can be stored in a small number or capacity of memory.
The instantaneous continuous reproduction described above can be realized for a large number of songs or information other than songs.

[0032]

DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment: Case of MD Changer System] As a first embodiment, a case where the present invention is applied to an MD changer system will be described.

(Basic Configuration of System) FIGS. 1 and 2
Shows the functional configuration of the MD changer system of this embodiment. Although the entire system is shown separately in FIGS. 1 and 2 for convenience, the system controllers in FIGS. 1 and 2 are the same.

The MD changer system of this embodiment is roughly divided into a disk box 31 capable of storing, for example, five disks 1a to 1e, and one of the disks 1 (in FIG. 1, the disk 1a is used as the disk 1a). A player box 32 for playing the disk 1a in the box 31 (shown by a broken line);
A stage controller 33 and a loading controller 34 for moving the disc between the player box 32 and the player box 32.

The stage controller 33 mounts any disc in the disc box 31 on the player box 32 according to an instruction from the system controller 11 constituted by, for example, a microcomputer in the player box 32, and
Disk 1 mounted on disk 2
The loading controller 34 determines which stage to return to, and according to the determination of the stage controller 33, loads the disc into the player box 32, removes the disc from the player box 32, and returns the disc to the disc box 31. However, a mechanism such as a loading motor, which is omitted in the drawing, is controlled.

A disc 1 which is a MD and is a magneto-optical disc mounted on a predetermined position of the player box 32
Is driven by a spindle motor 2 to irradiate the disk 1 from the optical head 3 with high-level laser light for heating the recording track to the Curie temperature during recording, and from the optical head 3 during reproduction with the laser.
Is irradiated with a relatively low level laser beam for reading information from the reflected light by the magnetic Kerr effect.

The optical head 3 includes an optical system including an objective lens 3a, a polarizing beam splitter, and the like, in addition to a laser diode that outputs laser light, a two-axis actuator 4,
And a light detector for detecting light reflected from the disk 1.

The objective lens 3a includes a biaxial actuator 4
Accordingly, the disk 1 can be moved in the radial direction and in a direction approaching the disk 1 or moving away from the disk 1. Further, the entire optical head 3 includes a thread mechanism 5
Thereby, the disk 1 can be moved in the radial direction.

Although not shown in the figure, a magnetic head for applying a magnetic field modulated by data to the disk 1 during recording is arranged at a position facing the optical head 3 with the disk 1 interposed therebetween. However, since the present invention does not directly relate to the recording, the description of the recording is omitted hereafter.

At the time of reproduction, the information read from the disk 1 by the optical head 3 is supplied to the RF amplifier 7, and the RF amplifier 7 performs arithmetic processing on the information.
Thus, a reproduction RF signal, a tracking error signal, a focus error signal, groove information (absolute position information recorded as a pre-groove (wobbling groove) on the disk 1), and the like are obtained.

The groove information from the RF amplifier 7 is decoded by the address decoder 10, and the absolute position information is obtained from the address decoder 10. Further, address information recorded on the disc 1 as data is extracted by the RF decoder 8. These absolute position information and address information are supplied to the system controller 11,
Used for various controls.

The tracking error signal and the focus error signal from the RF amplifier 7 are supplied to the servo circuit 9 together with a track jump command, an access command, rotation speed detection information, and the like from the system controller 11, and various signals are sent from the servo circuit 9. Is obtained, the two-axis actuator 4 is controlled by the servo control signal to perform tracking control and focus control, and the sled mechanism 5 is controlled to move the optical head 3 in the radial direction of the disk 1. At the same time, the rotation of the spindle motor 2 is controlled so that the disk 1 rotates at a constant linear speed.

The reproduced RF signal from the RF amplifier 7 is RF
The decoder 8 performs processing such as EFM demodulation and CIRC decoding, and outputs the disk data output 20 after the processing.
The data is slightly adjusted by the system controller 11 and is obtained as a reproduced data output 27 from the system controller 11.

As will be described later, the reproduced data output 27 is compressed by the data compression circuit 41 for the head data, and is not compressed for the TOC information and the data after the head data.
Is written to the memory block 12 by the system controller 11. Therefore, switches 40 and 42 are provided between the system controller 11 and the memory block 12 before and after the data compression circuit 41.

In the case of the MD, the data recorded therein is originally compressed by orthogonal transformation at the time of recording, but the data compression circuit 41 further converts the head data of the data by orthogonal transformation or the like. To compress. The compression ratio is, for example, 1/2.

The memory data input 21 written in the memory block 12 is read from the memory block 12 as a memory data output 22 by the system controller 11 as described later, and is slightly adjusted by the system controller 11.

The memory data output 28 after the adjustment processing
However, as described later, the head data is expanded by the data expansion circuit 44, and the data after the head data is supplied to the audio decoder 13 as the audio decoder input 23 without being expanded.
Therefore, switches 43 and 45 are provided before and after the data decompression circuit 44 between the system controller 11 and the audio decoder 13.

The data decompression by the data decompression circuit 44 is performed by converting the head data compressed by the data compression circuit 41 into
It restores the data before compression by the data compression circuit 41, and does not solve the original compression by orthogonal transformation at the time of recording.

In the audio decoder 13, the audio decoder input 23 is further decompressed so as to release the original compression.
Are subjected to inverse orthogonal transformation and data expansion, and a linear audio output 24 is obtained. This linear audio output 24
The analog audio signal 25 is converted into an analog audio signal 25 by the D / A converter 14, and the analog audio signal 25 is output to the audio output terminal 15.

(Memory Configuration) FIG. 3 shows an example of the memory block 12 of the first embodiment, in which head data after compression of a maximum of n music pieces of each of the disks 1a to 1e is stored in the head memory. This is the case when it is made to be performed. Here, n is an even number, and m = n−1.

The memory block 12 in this example has 0000
One main memory 12M having memory addresses from 0 to 7FFFF, and from 80000 to FFFFF respectively
.., 12Sm having memory addresses up to and including a memory 51, and a selector 51 controlled by the system controller 11. The selector 51 controls the head memories 12S1 to 12S1.
Select one of 2Sm.

The main memory 12M stores 00000 to 0F
A TOC memory area 12M1 for storing the above-described TOC information in the address area up to the FFF and a disk memory area 12M2 for storing data after the head part data in the address area from 10000 to 4FFFF are set.

In the disk memory area 12M2, under the control of the system controller 11, the memory data input 21 is stored while the last input address in the past is incremented. As a result, the input address becomes 4FFF.
When it reaches F, the next returns to the lower order and the address 100
A so-called ring buffer configuration in which data is stored continuously from 00 is provided.

In the course of the accumulation, the memory data input 21
When the input address reaches the output address of the memory data output 22, the system controller 11 stops accumulating data in the disk memory area 12M2.
Then, the area 1 where the data in the disk memory area 12M2 is stored by the system controller 11 is stored.
From 2M3, the memory data output 22 is read while the output address is incremented from the lower order.

In the case of MD, the memory data output 22 is incremented at a rate of 1/4 or less of the memory data input 21. Therefore, even if an error occurs in the reproduction data due to an external impact or the like, the music can be reproduced for a certain period of time by using the data stored in the storage area 12M3, and the error can be recovered during that time. By doing so, continuous reproduction can be guaranteed.

(System Initialization) In the MD changer system of this embodiment, when the system is initialized, for example, when power is supplied to the system, each of the disks 1a, 1b,
Compressed head data Da1 to Dan, Db1 to Dbn, Dc1 to 1c to 1d of the first to n-th songs
Dcn, Dd1 to Ddn, De1 to Den are stored in the head memories 12S1 to 12Sm.

The head data is stored in the head memories 12S1 to 12S1.
The order of the discs stored in the 2Sm can be arbitrarily set in the system. For example, at the start of the initialization process, the disc loaded in the player box 32 or the stage to be loaded is entered. If there is a disc that exists, the data at the head of the disc can be stored first,
As described later, at the time of initialization, if the user requests reproduction of a specific disc, the disc specified by the user is promptly reproduced.

In the following, in order to facilitate understanding, when the user has not requested reproduction of a specific disc, the head data after compression is stored in the order of the discs 1a, 1b, 1c, 1d, and 1e. The case is shown as an example.

First, the system controller 11 includes a stage controller 33 and a loading controller 34.
The first disk 1a is mounted on the player box 32 by controlling the operations described above.

After loading the disc 1a at a predetermined position of the player box 32, the system controller 11
First, a portion of the innermost portion of the disc 1a where the TOC information is recorded is accessed, and the TOC information of the disc 1a is accessed.
The C information is read, and the switches 40 and 42 are switched to the side opposite to the data compression circuit 41, and the TOC information is written to the TOC memory area 12M1 without compression.

Next, the system controller 11 detects, from the TOC information, an address at which the head data of the first tune of the disc 1a is recorded, accesses the address, and accesses the first tune of the disc 1a. The head data of the music is read, the switches 40 and 42 are switched to the data compression circuit 41 side, the head data is compressed to 1/2 by the data compression circuit 41, and the head memory 12S1 is selected by the selector 51. Then, the head data Da1 after compression is stored from the head address 80000 in the address area of 80000 to 87FFF corresponding to the first music piece of the disk 1a in the head memory 12S1.

Access to TOC information recording part, TO
It takes about 1 second to write the C information and access the recording address of the head data, and it takes about 4 seconds to store the compressed head data Da1.

The head part data Da1 after compression of the first music piece
If the user has not requested the reproduction of the specific disc at the time when all of the songs have been stored, the system controller 11 next calculates the second song of the disc 1a from the TOC information stored in the TOC memory area 12M1. An address at which the head data is recorded is detected, the address is accessed, the head data of the second music on the disk 1a is read, and the switches 40 and 42 are switched to the data compression circuit 41 side to read the head data. Data compression circuit 41
The head memory 12S1 is selected by the selector 51, and the compressed head data Da2 is stored in the disk 1a in the head memory 12S1.
The starting address 88000 is stored in the address area of 88000 to 8FFFF corresponding to the music piece.

The head data Da2 after the compression of the second music
If the user has not requested the reproduction of the specific disk at the point in time when all of the songs have been stored, the system controller 11 next calculates the third song of the disk 1a from the TOC information stored in the TOC memory area 12M1. The address at which the head data is recorded is detected, the address is accessed, the head data of the third music on the disk 1a is read, and the switches 40 and 42 are switched to the data compression circuit 41 side, and the head is read. Data compression circuit 41
The head memory 12S3 is selected by the selector 51, and the compressed head data Da3 is stored in the disk 1a in the head memory 12S3.
The starting address 80000 is stored in the address area of 80000 to 87FFF corresponding to the music piece.

Hereinafter, in the same manner, 4 to 4 of the disk 1a
Head part data Da4 to Da of the m and n tunes after compression
m and Dan are stored in the corresponding address areas in the head memories 12S3 to 12Sm.

At the time when all of the head data Da1 to Dan after compression of the first to n-th songs on the disk 1a are stored,
If the user has not requested the playback of a specific disc, the system controller 11 first controls the loading controller 34 to remove the disc 1a mounted on the player box 32 from the player box 32. Remove and return to the original position of disk box 31. The time required for this is about 1 second.

Next, the system controller 11 controls the stage controller 33 so that the disk box 3
1 is moved by one stage in this case. The time required for this is 4-5 seconds.

Further, the system controller 11 controls the loading controller 34 to move the next disc 1b from the disc box 31 to the player box 3
Attach to 2. The time required for this is about 1 second.

In this way, the next disc 1b is mounted at a predetermined position of the player box 32. The time required for this is 6-7 seconds.

After that, as in the case of the first disk 1a, the system controller 11
The C information is read and written to the TOC memory area 12M1 without compression, the head data of the first tune of the disk 1b is read, compressed by the data compression circuit 41 to １ ／, and The memory 12S1 is selected, and the head data Db1 after the compression is selected.
From the top address 90000 in the address area of 90000 to 97FFF corresponding to the first music piece of the disk 1b in the top memory 12S1.

The head data Db1 of the first music after compression
If the user has not requested the reproduction of the specific disc at the point in time when all have been stored, the system controller 11 then proceeds to the beginning of the second tune on the disc 1b as in the case of the first disc 1a. The head data 12b1 is read by the data compression circuit 41, the head memory 12S1 is selected by the selector 51, and the head data Db2 after compression is stored in the disk 1b in the head memory 12S1. The start address 98000 is stored in the address area of 98000 to 9FFFF corresponding to the tune.

Hereinafter, similarly, 3 and 4 of the disk 1b
-Head data Db3, Db after compression of the ｍm and n tunes
4 to Dbm and Dbn are stored in the head memories 12S3 to 12S.
m in the corresponding address area.

Further, by performing the same processing, the disk 1
Head data Dc1 to Dcn, Dd1 to Ddn, De1 to De after compression of the first to nth songs c, 1d, 1e
n is stored in the corresponding address area in the head memories 12S1 to 12Sm, and the system initialization ends.

Each of the address areas in the head memories 12S1 to 12Sm in which the compressed head data is stored is 1.6 Mbit. In the case of MD, the compressed head data is stored in the data as described later. Expansion circuit 44
, And the time of reproduction output when expanded by the audio decoder 13 is approximately 14
Since this corresponds to seconds, each of the address areas stores about 14 seconds of compressed head data as the reproduction output time.

However, the head part data Da1 to Den after compression of the first to n-th songs of all the disks 1a to 1e.
If the user requests the reproduction of a specific disk before is stored in the head memories 12S1 to 12Sm, the disk specified by the user is promptly reproduced as follows. A case where the user requests the reproduction of the second tune of the disc 1c is shown as an example.

In this case, first, the system controller 1
1 controls the stage controller 33, the loading controller 34, and the like, and mounts the disc 1c in the player box 32.

After loading the disc 1c at a predetermined position on the player box 32, the system controller 11
First, the TOC information of the disk 1c is read and written to the TOC memory area 12M1 without compression, and then, based on the TOC information, the head data of the second music of the disk 1c is read to perform data compression. Circuit 4
1, the head memory 12S1 is selected by the selector 51, and the compressed head data Dc2 is stored in an address of A8000 to AFFFF corresponding to the second music of the disk 1c in the head memory 12S1. The data is stored in the area from the start address A8000. It takes about 4 seconds to store all the head data Dc2 after compression.

After storing all the head data Dc2 after the compression of the second music on the disk 1c, the system controller 11 stores the output address of the memory data output 22 and the head data Dc2 after the compression. The start address A8000 of the address area is changed, and the compressed start data Dc2 of the second tune of the disk 1c is read out.
The switches 43 and 45 are switched to the data decompression circuit 44 side, and the head data Dc2 after the compression is decompressed by the data decompression circuit 44.

The head data of the second tune on the disk 1c after the expansion is supplied to the audio decoder 13 as an audio decoder input 23, and is subjected to inverse orthogonal transformation by the audio decoder 13 to expand the data.

Therefore, the disk 1 designated by the user
The beginning of the second tune of c is immediately reproduced. Since the leading part data Dc2 is about 14 seconds in time for reproduction output, the leading part is reproduced without interruption for about 14 seconds.

Thereafter, the system controller 11 calculates the next address position of the head data of the second song of the disc 1c from the TOC information stored in the TOC memory area 12M1 as described above, and places the optical head at that position. 3 is accessed. The time required for this is about 1 second.

After the access is completed, the system controller 1
1 switches the switches 40 and 42 to the side opposite to the data compression circuit 41 side, and the data from the accessed position, that is, the data after the head data of the second music on the disk 1c, is processed by the data compression circuit 41. Without compression, the main memory 12
The data is stored in the disk memory area 12M2 in M from the start address 10000.

At this time, the compressed head data Dc of the second music on the disk 1c is read from the head memory 12S1.
Since it is within 14 seconds from the start of reading of No. 2, the beginning of the second tune on the disc 1c is still being reproduced.

Then, from the start of reading out the compressed head data Dc2 from the head memory 12S1, about 1
Four seconds later, when all the heads of the second music on the disk 1c have been reproduced, the system controller 11 changes the output address of the memory data output 22 from the address AFFFF of the head memory 12S1 to the head address of the disk memory area 12M2. Change to 10000
The data after the head data of the tune of the tune is read, and the switches 43 and 45 are switched to the side opposite to the data decompression circuit 44 side.

The data after the read head data is:
Without being expanded by the data expansion circuit 44, the audio decoder 13
, And subjected to inverse orthogonal transform by the audio decoder 13 to expand the data.

Therefore, the disk 1 designated by the user
From the beginning of the second song of c to the subsequent portion,
Sound is played continuously without interruption.

The time required for storing all the data in the disk memory area 12M2 is about 15 seconds, and after the data starts to be read from the head address 10000 of the disk memory area 12M2, the memory data output 2
It takes about 50 seconds for the output address of No. 2 to reach the final address 4FFFF of the disk memory area 12M2.

Therefore, after that, in order to further continue the reproduction of the second music on the disc 1c specified by the user,
By about 50 seconds later, the subsequent data of the second song on the disk 1c must be stored in the disk memory area 12M2 again.
The compressed head data of the possible number of songs, such as the first and third tunes whose compressed head data has not yet been stored in the head memory, can be sequentially stored in the head memory.

Alternatively, from the time of about 50 seconds,
The disc 1c is again mounted in the player box 32, and the compressed data is still obtained within a time period obtained by subtracting a maximum time of about 10 seconds required to start storing the subsequent data of the second music piece of the disc 1c in the disk memory area 12M2. A disk in which the head data is not stored in the head memory can be mounted on the player box 32, and the compressed head data of the possible number of music pieces of the disk can be sequentially stored in the head memory.

As described above, at the time of system initialization, the specified music on the disk specified by the user is immediately and continuously reproduced from the beginning, and in parallel with this, the music on the disks 1a to 1e is The first part data Da1 to Den after compression of the first to nth pieces of music are stored in the first part memory 12S.
It is stored in 1 to 12 Sm.

(Playback after Initialization) In the system in which initialization has been completed, even if the disk needs to be replaced, the specified music on the disk specified by the user is immediately interrupted from the beginning without any sound interruption. Plays continuously. As an example, a case where the user requests reproduction of the fourth song on the disc 1b while playing a song on the disc 1a will be described.

In this case, at the time of the music selection operation by the user, since the disk 1a is mounted on the player box 32 and the disk 1a is being reproduced, the latest data of the disk 1a is stored in the storage area 12M3 in the main memory 12M. It is stored.

In this state, when the fourth tune on the disk 1b is selected, the system controller 11 selects the head memory 12S3 by the selector 51 and sets the output address of the memory data output 22 in the storage area 12M3. From the last read address of the memory data output 22 of the disk 1b in the head memory 12S3
Is changed to the start address 98000 of the address area in which the compressed head data Db4 of the fourth tune is stored, and the compressed head data Db4 of the fourth tune on the disk 1b is read out. 45 is switched to the data decompression circuit 44 side, and the read compressed head part data Db4 is decompressed by the data decompression circuit 44.

The head data of the fourth music piece of the expanded disk 1b is supplied to the audio decoder 13 as an audio decoder input 23, and is subjected to inverse orthogonal transformation by the audio decoder 13 to expand the data.

Therefore, immediately after the music selection operation by the user, the head of the fourth music on the disc 1b specified by the user is reproduced. Since the leading part data Db4 is equivalent to a reproduction output time of about 14 seconds, the leading part is reproduced without interruption for about 14 seconds.

In parallel with this, the system controller 1
First, 1 controls the loading controller 34, removes the disc 1a mounted on the player box 32 at this time from the player box 32, and returns the disc 1a to the original position of the disc box 31. The time required for this is about 1 second.

Next, the system controller 11 controls the stage controller 33 so that the disk box 3
1 is moved by one stage in this case. The time required for this is 4-5 seconds.

Further, the system controller 11 controls the loading controller 34 to mount the disc 1b specified by the user from the disc box 31 to the player box 32. The time required for this is about 1
Seconds.

In this way, the disc 1b designated by the user is mounted at a predetermined position of the player box 32. The time required for this is 6-7 seconds.

Thereafter, the system controller 11 sets the TOC memory area 12M1
Is calculated based on the TOC information stored in the disk 1b, and the optical head 3 is made to access the position of the next address of the head data of the fourth piece of music on the disk 1b. The time required for this is about 1 second.

After the access is completed, the system controller 1
1 switches the switches 40 and 42 to the side opposite to the data compression circuit 41 side, and the data from the accessed position, that is, the data after the head data of the fourth music piece of the disk 1b, is transmitted by the data compression circuit 41. Without compression, the main memory 12
The data is stored in the disk memory area 12M2 in M from the start address 10000.

At this time, since it is within 14 seconds from the time of the music selection operation by the user, the head of the fourth music on the disc 1b is still being reproduced.

Then, from the time of the music selection operation by the user, about 1
Four seconds later, when the beginning of the fourth tune on the disk 1b is completely reproduced, the system controller 11 sets the output address of the memory data output 22 from the address 9FFFF.
Start address 10000 of disk memory area 12M2
To read the data subsequent to the head data of the fourth tune on the disk 1b, and switch 43 and 4
5 is switched to the side opposite to the data decompression circuit 44 side.

The data after the read head data is:
Without being expanded by the data expansion circuit 44, the audio decoder 13
, And subjected to inverse orthogonal transform by the audio decoder 13 to expand the data.

Therefore, the disk 1 designated by the user
From the beginning of the fourth song of b to the subsequent part,
Sound is played continuously without interruption. Subsequent processing is the same as that of the system in which the head data is not stored in the memory.

(Effects) According to the first embodiment described above, in the MD changer system, the head data of the first to n-th songs of each of the disks 1a to 1e is compressed by the data compression circuit 41 and the first data is compressed. Unit memory 1
Since the data is stored in the 2S1 to 12Sm, the head data of a large number of songs can be stored in a small number or capacity of memory. Thus, the music specified on the disk specified by the user can be immediately and continuously reproduced from the head without interruption.

[Second Embodiment: In the Case of a CD Changer System] In the MD, data read from the MD is already compressed, and the MD has time information inside the disc. The head data compressed by the data compression circuit 41 also has time information. Therefore, in the case of the MD changer system, as in the first embodiment described above, the data is compressed by the data compression circuit 41, written to the head memory, read from the head memory, and decompressed by the data decompression circuit 44. The head data and the data after the head data read from the disk can be easily connected.

On the other hand, in the case of a CD, although a disc contains time information, a system controller, a memory and an audio decoder of a CD changer system, which are often used at present, use one signal processing LSI. As an independent structure. Moreover, the reproduced data output 27 and the memory data output 22 shown in FIG.
A portion corresponding to the portion between the two is built in the signal processing LSI and has a structure in which memory data output cannot be controlled from outside.

Therefore, in the CD changer system, when the signal processing LSI which is currently used frequently is used alone, the head data read from the head memory and the data after the head data read from the disk are used. It is not easy to connect, and even if the disc needs to be replaced as in the first embodiment in the case of the MD changer system, the sound of the target music is immediately interrupted from the beginning. It is not easy to make it reproduced continuously without any change. To achieve this feature,
Signal processing LSI for system controller, memory and audio decoder part of CD changer system
Needs to be changed to a special one. However, this comes at a cost.

However, the signal processing LSI for CD is
The time information contained therein can be given to the system controller as a subcode, and the subcode can control the timing of the reproduction data output from the signal processing LSI for CD.

Further, the system controller 11 of the MD changer system of the first embodiment can freely transfer the output data of the data compression circuit 41 to the memory block 12, and output the data output 22 of the memory block 12 The data can be freely transferred to the data decompression circuit 44. Therefore, the reproduced data output from the signal processing LSI for CD is transferred to the data compression circuit 41. By monitoring the code, the data decompression circuit 44
Can accurately control the timing of the output data.

Therefore, in the system shown in FIGS. 1 and 2, the mechanical part including the part of the system controller 11 up to the part for obtaining the reproduced data output 27 and the signal processing part are the mechanical part of the CD changer system. CD
System controller 1 using a signal processing LSI for
In the case of a CD changer system, the data is compressed by the data compression circuit 41 and written into the head memory, and the head signal is processed by using a signal processing LSI for MD as a subsequent signal processing unit including a part of the first part. After the data is read from the memory, the head data expanded by the data expansion circuit 44 and the data after the head data read from the disk can be easily connected, resulting in a relatively simple increase in system cost. Even if it is necessary to change the disk without much delay, the desired music can be immediately and continuously reproduced from the head without interruption.

In the second embodiment, the present invention is applied to a CD changer system by such a method. As described above, the system controller 11
As a mechanism and a signal processing unit up to a part for obtaining the reproduction data output 27 including a part of the above, a mechanism of a CD changer system and a signal processing LSI for CD are used.
In the systems shown in FIGS. 1 and 2, the mechanism and the signal processing unit up to the part where the reproduced data output 27 is obtained, including a part of the system controller 11, are directly used as the mechanism of the CD changer system and the signal processing for the CD. LSI
1 and 2 show the CD changer system of the second embodiment as it is.

(Basic Configuration of System) In the second embodiment, the disc box 31 stores CDs as the discs 1a to 1e.
Is for mounting and reproducing a CD as the disk 1.

The CD changer system of this embodiment is also roughly divided into a disk box 31, a player box 32, a stage controller 33, and a loading controller. Stage controller 3
3 and the function of the loading controller 34
This is the same as the embodiment.

The disk 1 is driven to rotate by the spindle motor 2, and at the time of system initialization and reproduction,
As in the first embodiment, the optical head 3 irradiates the disk 1 with a relatively low-level laser beam for reading information from reflected light.

The structure of the optical head 3, tracking control,
Focus control, radial movement of the optical head 3 of the disk 1 by the sled mechanism 5, and spindle motor 2
The rotation control of the disk 1 is also the same as in the first embodiment.

However, since this embodiment is a case of a CD, not the groove information but the information inherent in the reproduced RF signal is decoded by the address decoder 10, and the absolute position information is obtained from the address decoder 10. . The address information recorded on the disk 1 as data is extracted by the RF decoder 8 as in the first embodiment.

The reproduction RF signal from the RF amplifier 7 is RF
The decoder 8 performs processing such as EFM demodulation and CIRC decoding, and outputs the disk data output 20 after the processing.
It is the same as in the first embodiment that the data is slightly adjusted by the system controller 11 and obtained as a reproduction data output 27 from the system controller 11.

In this embodiment, the switch 40
And 42 are always switched to the data compression circuit 41 side, and switches 43 and 45 are always switched to the data decompression circuit 44.
Can be switched to the side.

The data compression circuit 41 is an encoder used for recording an MD. In this embodiment, the reproduced data output 27 after the disk data output 20 is adjusted by the system controller 11 is subjected to an orthogonal transformation. The data is compressed to about 1/4 to obtain a memory data input 21 to which time information is added.

The memory data input 21 is written to the memory block 12 and read from the memory block 12 as the memory data output 22, as described later.

The data decompression circuit 44 is a decoder portion used for reproducing the MD. In this embodiment, the data decompression circuit 44 converts the memory data output 28 after the memory data output 22 is adjusted by the system controller 11 into an inverse orthogonal transform. The data is decompressed to restore the original CD data, and the audio decoder input 23 is obtained.

As the data compression circuit 41 and the data decompression circuit 44 of this embodiment, those mass-produced as an MD encoder and decoder can be used as they are.

Since this embodiment is for a CD,
The audio decoder 13 outputs the audio decoder input 2
3 without data decompression, simply D / A converter 1
4 interface.

(Memory Configuration) FIG. 4 shows an example of the memory block 12 according to the second embodiment, in which head data after compression of a maximum of x songs of each of the disks 1a to 1e is stored in the head memory. This is the case when it is made to be performed.

In this example, the memory block 12 has
One main memory 12M having memory addresses from 0 to 7FFFF, and from 80000 to FFFFF respectively
X head memories 12 having memory addresses up to
S1, 12S2... 12Sx and the system controller 1
The selector 51 controls one of the head memories 12S1 to 12Sx.

The main memory 12M is the same as the example shown in FIG. 3 of the first embodiment. In the second embodiment, since the reproduced data output 27 is compressed to about 1/4 by the data compression circuit 41 as described above, each of the head memories 12S1 to 12Sx stores 80000 to 8F
FFF, 90000-9FFFF, A0000-AFF
FF, B0000-BFFFF, C0000-CFFF
F to the address areas of the disks 1a, 1b, 1
One of the tunes c, 1d, and 1e is set as an area for storing compressed head data.

(System Initialization) As in the first embodiment, the order of disks for storing head data in the head memories 12S1 to 12Sx can be set arbitrarily in the system. At the time of initialization, if the user requests reproduction of a specific disc, the disc specified by the user is promptly reproduced.

In the following, in order to facilitate understanding, when the user does not request reproduction of a specific disk, the head data after compression is stored in the order of disks 1a, 1b, 1c, 1d, and 1e. The case is shown as an example.

First, the system controller 11 includes a stage controller 33 and a loading controller 34.
The first disk 1a is mounted on the player box 32 by controlling the operations described above.

After mounting the disc 1a at a predetermined position on the player box 32, the system controller 11
First, a portion of the innermost portion of the disc 1a where the TOC information is recorded is accessed, and the TOC information of the disc 1a is accessed.
The C information is read, and only at this time, the switches 40 and 42 are switched to the side opposite to the data compression circuit 41, and the TOC information is written to the TOC memory area 12M1 without compression.

Next, the system controller 11 detects, from the TOC information, the address where the head data of the first music piece of the disc 1a is recorded, accesses the address, and accesses the address of the first music piece of the disc 1a. The head data of the tune is read, the switches 40 and 42 are switched to the data compression circuit 41 side, the head data is compressed to about 1/4 by the data compression circuit 41, and the head memory 12S1 is selected by the selector 51. Then, the head data Da1 after compression is stored from the head address 80000 in the address area of 80000 to 8FFFF corresponding to the disk 1a in the head memory 12S1.

Access to TOC information recording portion, TO
It takes about 1 second to write the C information and access the recording address of the head data, and it takes about 4 seconds to store the compressed head data Da1.

[0135] Head part data Da1 after compression of the first music piece
If the user has not requested the reproduction of the specific disc at the time when all of the songs have been stored, the system controller 11 next calculates the second song of the disc 1a from the TOC information stored in the TOC memory area 12M1. The address at which the head data is recorded is detected, the address is accessed, the head data of the second music of the disk 1a is read, and the data is compressed by the data compression circuit 41 to about 1/4. The head memory 12S2 is selected in accordance with the above, and the compressed head data Da2 is stored in the memory 80000 to 80000 corresponding to the disk 1a in the head memory 12S2.
In the address area of FFFF, the start address 8000
Store from 0.

In the same manner, the compressed head data of the music pieces up to the x-th music piece of the disk 1a are stored in the address area corresponding to the disk 1a in the corresponding head memory.

When all of the head data Da1 to Dax after the compression of the first to x-th songs on the disk 1a are stored,
If the user has not requested the playback of a specific disc, the system controller 11 first controls the loading controller 34 to remove the disc 1a mounted on the player box 32 from the player box 32. Remove and return to the original position of disk box 31. The time required for this is about 1 second.

Next, the system controller 11 controls the stage controller 33 so that the disk box 3
1 is moved by one stage in this case. The time required for this is 4-5 seconds.

Further, the system controller 11 controls the loading controller 34 to move the next disc 1b from the disc box 31 to the player box 3
Attach to 2. The time required for this is about 1 second.

In this way, the next disc 1b is mounted at a predetermined position of the player box 32. The time required for this is 6-7 seconds.

Thereafter, as in the case of the first disk 1a, the system controller 11
The C information is read and written into the TOC memory area 12M1 without compression, the head data of the first tune on the disk 1b is read, compressed by the data compression circuit 41 to about 1/4, and Section memory 12S1 and the head section data Db after the compression
1 is stored in the address area of 90000 to 9FFFF corresponding to the disk 1b in the head memory 12S1 from the head address 90000.

[0142] Head part data Db1 after compression of the first music piece
If the user has not requested the reproduction of the specific disc at the point in time when all have been stored, the system controller 11 then proceeds to the beginning of the second tune on the disc 1b as in the case of the first disc 1a. The data is read by the data compression circuit 41 and compressed by the data compression circuit 41 to about 1/4.
Then, the head memory 12S2 is selected, and the compressed head data Db2 is stored from the head address 90000 in the address area of 90000 to 9FFFF corresponding to the disk 1b in the head memory 12S2.

In the same manner, the compressed head data of the songs up to the x-th song on the disk 1b is stored in the address area corresponding to the disk 1b in the corresponding head memory.

Further, by performing the same processing, the disk 1
Head part data Dc1 to Dcx, Dd1 to Ddx, De1 to De after compression of the first to x-th songs c, 1d, and 1e
x is stored in the address area corresponding to the disks 1c, 1d, and 1e in the corresponding head memories 12S1 to 12Sx, and the system initialization ends.

Each of the address areas of the head memories 12S1 to 12Sx in which the compressed head data is stored is 3.2 Mbits. In the case of a CD, the compressed head data is stored in the data as described later. Expansion circuit 44
Since the time corresponding to the reproduction output when the data is decompressed is equivalent to about 14 seconds, the compressed head data corresponding to the reproduction output time corresponding to about 14 seconds is stored in each address area. Will be done.

[0146] However, the first part data Da1 to Dex of the first to x-th songs of all the disks 1a to 1e after compression.
If the user requests the reproduction of a specific disk before is stored in the head memories 12S1 to 12Sx, the disk specified by the user is promptly reproduced. According to the second embodiment, in the second embodiment, the data after the head data written in the disk memory area 12M2 of the main memory 12M is also compressed by the data compression circuit 41, and the data read from the disk memory area 12M2 is compressed. Since it is the same as the first embodiment except that the data is expanded by the data expansion circuit 44, the description is omitted.

(Playback after Initialization) In the system in which initialization has been completed, even when the disk needs to be replaced, the specified music on the disk specified by the user is immediately and without interruption of sound from the beginning. Plays continuously. As an example, a case where a user requests reproduction of a second music piece on the disc 1b while playing a music piece on the disc 1a will be described.

In this case, at the time of the music selection operation by the user, since the disk 1a is mounted on the player box 32 and the disk 1a is being reproduced, the latest data of the disk 1a is stored in the storage area 12M3 in the main memory 12M. It is stored.

In this state, when the second tune on the disk 1b is selected, the system controller 11 selects the head memory 12S2 by the selector 51 and sets the output address of the memory data output 22 in the storage area 12M3. From the last read address of the memory data output 22 of the disk 1b in the head memory 12S2
Is changed to the start address 90000 of the address area in which the compressed head data Db2 of the second music is stored, and the compressed head data Db2 of the second music of the disk 1b is read out. While the data 45 is being switched to the data decompression circuit 44, the read compressed head part data Db 2 is decompressed by the data decompression circuit 44 and output to the audio decoder 13.

Therefore, immediately after the music selection operation by the user, the head of the second music on the disc 1b specified by the user is reproduced. Since the head part data Db2 is equivalent to a reproduction output time of about 14 seconds, the head part is reproduced without interruption for about 14 seconds.

In parallel with this, the system controller 1
First, 1 controls the loading controller 34, removes the disc 1a mounted on the player box 32 at this time from the player box 32, and returns the disc 1a to the original position of the disc box 31. The time required for this is about 1 second.

Next, the system controller 11 controls the stage controller 33 so that the disk box 3
1 is moved by one stage in this case. The time required for this is 4-5 seconds.

[0153] Further, the system controller 11 controls the loading controller 34 to mount the disc 1b designated by the user from the disc box 31 to the player box 32. The time required for this is about 1
Seconds.

In this way, the disc 1b designated by the user is mounted on the player box 32 at a predetermined position. The time required for this is 6-7 seconds.

Thereafter, the system controller 11 sets the TOC memory area 12M1
Is calculated based on the TOC information stored in the first song, and the optical head 3 is made to access the position of the next address of the head data of the second song of the disc 1b. The time required for this is about 1 second.

After the access is completed, the system controller 1
1 indicates that the data from the accessed position, that is, the data after the head data of the second music piece on the disk 1b, is kept by the data compression circuit 41 for about 1 while the switches 40 and 42 are switched to the data compression circuit 41 side. / 4, and the compressed data after the head data is used as the memory data input 21 in the disk memory area 12M2 in the main memory 12M and the head address 10000 is stored.
Store from.

At this time, since the time is within 14 seconds from the time of the music selection operation by the user, the head of the second music of the disc 1b is still being reproduced.

[0158] Then, from the time of the music selection operation by the user, about 1
Four seconds later, when the beginning of the second song on the disk 1b has been completely reproduced, the system controller 11 sets the output address of the memory data output 22 from the address 9FFFF.
Start address 10000 of disk memory area 12M2
And reads out the compressed data after the head data of the second music piece on the disk 1b. While the switches 43 and 45 are being switched to the data decompression circuit 44, the compressed data after the read head data is read out. The expanded data is expanded by the data expansion circuit 44, and the audio decoder 1
Output to 3.

Therefore, the disc 1 designated by the user
From the beginning of the second song of b to the subsequent part,
Sound is played continuously without interruption. Subsequent processing is performed in the disk memory area 1 in the second embodiment.
The data after the head data written to 2M2 is also compressed by the data compression circuit 41, and the data read from the disk memory area 12M2 is
4, except that the head data is not stored in the memory.

(Effects) As described above, according to the second embodiment, the head part data and the data after the head part data are compressed by using the encoder part for MD as the data compression circuit 41, and The data is written into the memories 12S1 to 12Sx and the main memory 12M.
By expanding the compressed head data read from the main memory 12M and the compressed data after the head data, it is possible to relatively easily increase the cost of the system in the CD changer system. Even if the disc needs to be replaced without coming in, the target song can be played immediately and continuously from the beginning without interruption, and with a small number or capacity of memory. ,
Such instantaneous continuous reproduction can be realized for a large number of songs.

[Other Embodiments] The main memory and the head memory are not separate memories as in the above-described embodiment.
It may be a separate area of one memory.

In the above embodiment, the recording medium is M
In the case of D or CD, the present invention
It can also be applied to a disc changer system for a disc other than the disc and a recording medium other than the disc. The information recorded on the recording medium and reproduced from the recording medium is not limited to music, but may be an image or other information.

[0163]

As described above, according to the present invention, the head data is stored in the memory in advance, so that even when the recording medium needs to be replaced, the designated recording medium specified by the user can be used. In a reproducing apparatus in which information is immediately and continuously reproduced from the head without interruption, realization of such instantaneous continuous reproduction of a large number of music or information other than music is realized by a small number or a small amount of memory. be able to.

[Brief description of the drawings]

FIG. 1 is a diagram showing a part of a functional configuration of an embodiment when the present invention is applied to an MD or CD changer system.

FIG. 2 is a diagram illustrating another part of the functional configuration of the embodiment of FIG. 1;

FIG. 3 is a diagram illustrating an example of a memory configuration according to a first embodiment applied to an MD changer system.

FIG. 4 is a diagram illustrating an example of a memory configuration according to a second embodiment applied to a CD changer system.

FIG. 5 is a diagram showing an example of a memory configuration that can be considered when realizing instantaneous continuous reproduction.

[Explanation of symbols]

1, 1a-1e: disk, 2: spindle motor, 3
... optical head, 7 ... RF amplifier, 8 ... RF decoder, 1
1 ... system controller, 12 ... memory block, 1
2M: Main memory, 12S1 to 12Sm, 12S1 to 12
Sx: Head memory, 13: Audio decoder, 14
... D / A converter, 31 ... Disk box, 32 ...
Player box, 33 ... Stage controller, 3
4 loading controller, 41 data compression circuit, 44 data expansion circuit, 51 selector

Claims (2)

[Claims] 1. A reproducing apparatus capable of storing a plurality of recording media, of which a selected one of the recording media is mounted at a predetermined position and which reproduces the data read from the recording media. Sub-storage means for storing the head data of the recording medium of the present invention, wherein at the time of device initialization, the head data read from each recording medium is compressed by a data compression circuit and stored in the sub-storage means, Reading the corresponding compressed head data from the sub-storage means, decompressing and outputting the data by a data decompression circuit, reading the data after the head data from the corresponding recording medium, and writing the data to the main storage means, A reproducing apparatus for reproducing a requested recording medium by reading out and outputting from the main storage means. 2. The reproducing apparatus according to claim 1, wherein at the time of reproduction, data after the head data read from a corresponding recording medium is compressed by said data compression circuit and written in said main storage means. A compressed data after the head data read from the data decompression circuit, the data being decompressed and output by the data decompression circuit.