JPH10149609A - Optical disk reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the optical disk reproducing device equipped with a function for reproducing all programs recorded on an optical disk, at random in order without requiring a memory for storing reproducing order and capable of altering a program or programs to be reproduced, at any time. SOLUTION: Program data read out of the optical disk 1 are once stored in a DRAM 5, and are outputted under control of a system controller 13. The DRAM 5 has a sector structure having a header part for recording data management information and a data part for recording the program data, and these program data to be recorded in the data part, one bit of information for specifying reproducing order of these program data and one bit of information for specifying a shuffling pattern are recorded as shuffle management information in the header part. The next music data to be read out of the optical disk 1 is decided based on this shuffle management information.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for reproducing a plurality of programs recorded on an optical disk in a random order.
The present invention relates to an optical disk reproducing device having a so-called shuffle reproducing function.

[0002]

2. Description of the Related Art An optical disc is used as a recording medium which has an excellent feature that a large amount of data can be recorded at high density and random access is possible. For example, in an optical disk having a diameter of 64 mm and capable of recording music data having a maximum reproduction time of 74 minutes, the track on which the music data is recorded as a digital signal is approximately 1.6 μm.
They are provided at m intervals. As described above, when reading data from an optical disk on which data is recorded at a high density,
When a mechanical vibration, a shock, or the like is applied from the outside, the read head deviates from a predetermined track, and it becomes impossible to accurately read target data.

Therefore, in a reproducing apparatus for reproducing a program such as music data recorded on an optical disk as a high-density recording medium, music reproduction is interrupted even when reading of the music data is temporarily interrupted by disturbance. In order to avoid this (jump of sound), storage means (so-called shock proof memory) for temporarily storing and outputting music data read out from the optical disk without outputting the data in real time is provided. Usually this storage means is DR
It is configured using a semiconductor memory device such as an AM (Dynamic Random Access Memory).

The above-described optical disk reproducing apparatus has a so-called shuffle reproducing function of reproducing the music data of a plurality of recorded music pieces in a random order by utilizing the random accessibility of the optical disk. It is normal to do. In the case of performing the shuffle reproduction by the above-described reproducing apparatus configured to temporarily store the music data read from the optical disk in a storage means such as a DRAM and then reproduce the music data, the reading of the music data for one music from the optical disk is completed. And a song number indicating the song being played at that time and a shuffle pattern used to specify the playback order, and a song number of the next song to be read from the optical disc is determined. The procedure of reading the music data from the optical disk and storing it in the DRAM is repeated.

[0005] However, when the amount of music data stored in the DRAM is small (the music is short), the music data of a plurality of music may be stored in the DRAM. At this time, the reproduction of the music data already stored in the DRAM is stopped (skipped), and
When an instruction to play another song for which music data is not stored in the AM is input, in order to newly store the music data for that song, all of the plurality of music data already stored in the DRAM are discarded ( Clear) and the music that should have been played was not played.

In order to avoid such a problem, for example, all shuffle patterns are changed to SRAM (Static Ran).
dom Access Memory) or the like, and each time reading of music data for one song from the DRAM is completed, the shuffling pattern stored in the SRAM is referred to, and then the data is read from the optical disk. It has been practiced to obtain a song number to be read. But,
For example, the song numbers indicating a plurality of songs (music data) recorded on the optical disc can be designated up to 255 songs on an optical disc capable of recording music data having a diameter of 64 mm and a playback time of up to 74 minutes. A large memory capacity is required for the storage means for storing the shuffle reproduction order of the song. This leads to an increase in the cost of the reproducing apparatus and an increase in the circuit scale, which is not preferable as a method for use in a portable reproducing apparatus which is required to be smaller and less expensive.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and does not require any special storage means for storing the shuffle reproduction order. It is an object of the present invention to provide an optical disc reproducing apparatus having a shuffle reproducing function that can be changed at any time.

[0008]

An optical disk reproducing apparatus according to the present invention, proposed to solve the above-mentioned problems, arranges program numbers for designating all programs recorded on an optical disk without duplication in a random order. Reproducing order pattern generating means for generating a reproducing order pattern, reading means for sequentially reading data of a program specified by each program number forming the reproducing order pattern from the optical disk, and data of the program read by the reading means Storage means for storing the program data stored in the storage means, a control means for controlling the accumulation and reading operations of the program data, a reproduction means for reproducing the program data read from the storage means, and a reproduction means for reproducing the program data. Based on the program number of the program and the playback order pattern. An optical disc reproducing apparatus comprising: a selecting unit for selecting a program number of a program to be read next from a disk, wherein the storage unit stores, together with the data of the program, what number of the reproducing order pattern the program number is. And information to be stored.

According to this optical disk reproducing apparatus, there is no need to provide a storage means such as an SRAM for storing the shuffle reproducing order, and the optical disk reproducing apparatus has a shuffle reproducing function capable of changing the program to be reproduced at any time. Can be provided.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of an optical disk reproducing apparatus according to the present invention will be described below with reference to the drawings. In the following description, the optical disk is assumed to be a read-only optical disk capable of recording music data having a diameter of 64 mm and a reproduction time of up to 74 minutes or a rewritable magneto-optical disk.

FIG. 1 is a block diagram showing a configuration example of a main part of an optical disk reproducing apparatus to which the present invention is applied. The optical disc reproducing apparatus includes an optical pickup 2 for optically reading a program such as music data recorded as a digital signal on an optical disc 1, an RF amplifying unit 3 for amplifying the read data, and a demodulation of the amplified data. EF to do
An M & CIRC decoder 4; a DRAM 5 for temporarily storing demodulated data; a memory controller 6 for controlling data storage and reading operations of the DRAM 5; a voice compression decoder 7 for expanding voice-compressed data; It comprises a D / A converter 8 for converting to a music signal, and an address decoder 9 for demodulating a code indicating an address of data recorded on the optical disc 1. Further, the optical disk reproducing apparatus includes a feed motor 10 for feeding the position of the optical pickup 2, a spindle motor 11 for rotating and driving the optical disk 1, and a servo control circuit 12 for controlling these motors.

The EFM & CIRC decoder 4, the memory controller 6, and the servo control circuit 12 are a system controller 13 for controlling the operation of the entire optical disc reproducing apparatus.
And various control signals are transmitted and received. The system controller 13 is connected to a display unit 14 for displaying an operation state of the optical disk reproducing apparatus and operation keys 15 for inputting an operation instruction.

An optical pickup 2 for optically reading music data from an optical disk 1 on which a plurality of music data are recorded includes a laser light source such as a semiconductor laser (not shown), a lens for converging laser light, and an optical disk 1. And a photodiode for detecting reflected light of the light. The focus of the lens is controlled by the servo control circuit 12 so that the laser light from the laser light source always focuses on the recording layer of the optical disc 1 to form a minute light spot. The optical pickup 2 has a feed motor 10 controlled by a system controller 13 through a servo control circuit 12.
As a result, the position is moved to a recording area (track) on the optical disk 1 on which the selected music data is recorded (seek).
Further, tracking control is performed so that the spot of the laser beam is always located on the track. Then, the reflected light from the track on which pits or the like corresponding to the music data, which is a digital signal, is formed is optically modulated, converted into an electric signal by the photodiode, and the music data is read.

The RF amplifier 3 amplifies the music data read by the optical pickup 2 and converted into an electric signal to a predetermined level, performs processing such as equalization, and performs EFM & CI.
It is supplied to the RC decoder 4.

The EFM & CIRC decoder 4 is for demodulating the music data supplied from the RF amplifying unit 3, and converts Eight-bit data into 14-bit data by EFM (Eight to Fourteen Modulation) demodulation and error correction. CIRC (Cross Interleave Reed-
Performs demodulation of Solomon Code). The CIRC is a product code composed of a product of two error correction code sequences for generating and adding a parity and performing error correction when music data is erroneously read from the optical disc 1.

When the optical disk 1 on which the music data and the like are recorded is a reproduction-only optical disk, the address code recorded as sub data is also decoded and output.

The DRAM 5 interrupts the output of the music signal even when the reading of the music data is temporarily interrupted by a disturbance such as a mechanical vibration or a shock while reading the music data from the optical disc 1 (sound). This is a storage means provided to avoid jumping, and is a semiconductor memory element having a function as a data buffer. This D
The amount of music data stored in the RAM 5 is, for example, that when the storage capacity is 1 Mbit, music data can be stored from the optical disc 1 for about 0.9 seconds, and a music signal is reproduced using the music data for about 3 seconds. Is about to be possible.

The music data read from the optical disk 1 is not output in real time, but is temporarily stored in the DRAM 5 and then output via the audio compression decoder 7 and the like under the control of the memory controller 6.

The memory controller 6 always refers to an address on the optical disk 1. When the reading of music data is interrupted, the memory controller 6 immediately controls the reading of the music data from that address onward from the DRAM 5, thereby controlling
The control is performed so that the output of the music signal is not interrupted.

The audio compression decoder 7 is for expanding the music data compressed and recorded on the optical disk 1. This optical disc playback apparatus uses a high-efficiency audio compression technology that divides music data into frequency bands and uses the audibility characteristics in each frequency band to perform bit compression while preventing sound quality from deteriorating. It is recorded on the optical disk 1 after being compressed about five times. The audio compression decoder 7 expands the compressed music data read from the DRAM 5 by about 5 times and supplies it to the A / D converter 8.
The music data stored on the optical disk 1 is compressed and encoded, and the transfer rate when the compressed and encoded music data is stored in the DRAM 5 and the expansion / decompression
This is different from the transfer rate when the signal is decoded and output as a music signal. The transfer rate of the music data will be described later.

The A / D converter 8 converts the digital music data expanded by the audio compression decoder 7 into an analog signal and outputs it as a music signal.
It is configured using a bit A / D converter.

When a rewritable magneto-optical disc is used as the optical disc 1, the address decoder 9 decodes an address code recorded over the entire circumference thereof to perform E-decoding.
This is for supplying to the FM & CIRC decoder 4. The address of the magneto-optical disk is recorded on the entire circumference of the disk by a method called wobbling or the like in which a pre-groove (groove) formed in advance is slightly meandered. As described above, when a read-only optical disk in which a pre-groove is not used is used as the optical disk 1, an address is recorded by decoding the address code recorded as sub-data by the EFM & CIRC decoder 4.

When the reading of the music data from the optical disk 1 is temporarily interrupted by disturbance such as mechanical vibration or shock, the memory controller 6 reads the music data by referring to this address. Is detected, and control is performed to immediately read the music data from that address onward from the DRAM 5.

The servo control circuit 12 controls the music data of the music number specified by the system controller 13 so that the music data can be correctly read from a predetermined track of the optical disk 1. The position control of the feed motor 10 for seeking the optical pickup 2 and the rotation control of the spindle motor 11 for driving the optical disk 1 to rotate are performed.

The system controller 13 controls the entire operation of the optical disk reproducing apparatus. The system controller 13 is connected to the EFM & CIRC decoder 4, the memory controller 6, the servo control circuit 12, etc., and sends and receives various control signals. doing. When performing shuffle reproduction with this optical disk reproducing apparatus, the system controller 13
Determines the playback order of the songs. Specifically, a reproduction order pattern of music data is generated based on a random number sequence supplied from a random number sequence generation circuit (not shown) or the like. In this optical disc reproducing apparatus, a maximum length sequence code called an M sequence is used. Thus, the program reproduction order is generated. Various other means are known as means for generating a random number sequence, and these may be used appropriately.

Among the random numbers obtained by such means, random numbers equal to or less than the number of songs recorded on the optical disc 1 are sequentially assigned to music data of each song, and a song number designating the song is assigned. For example, when generating a shuffle pattern for reproducing music data of all five songs recorded on the optical disc 1 in a random order, the random number sequence generating means 98,2
3,2,46,5,122,31,6,3,43,1,
Assuming that a random number sequence of 90, 88, 21, 4,... Is obtained, a sequence of five numbers 2, 5, 3, 1, and 4, which are sequentially extracted from numbers less than 5 that appear in the sequence, It becomes a reproduction order pattern. Each number forming the playback order pattern is a song number indicating a song to be played. That is, the reproduction order determined based on the reproduction order pattern is: song number 2 → song number 5 → song number 3 → song number 1 → song number 4.

In order to prevent the same order of reproduction from being performed each time the shuffle reproduction is performed, a plurality of different shuffle patterns are generated by a method such as generating a random number sequence using a signal from the time information generating means as a seed. You should be able to do it.

The display unit 14 is provided with the system controller 13
And for displaying the operation state of the optical disk reproducing apparatus. The operation keys 15 are
This is for inputting an operation instruction to the optical disk reproducing apparatus, and is used for inputting an instruction to select a shuffle reproduction mode or to skip a tune not desired to be reproduced during shuffle reproduction.

Next, the operation of each section of the optical disk reproducing apparatus having the above-described configuration will be described along the flow of music data reproduced from the optical disk 1 with reference to FIG.

As described above, this optical disc reproducing apparatus uses the optical disc 1 to avoid sound skipping due to disturbance.
The music data read out from the memory is not output in real time, but is temporarily stored in the DRAM 5 functioning as a data buffer, and then output under the control of the memory controller 6. Therefore, the optical pickup 2
Does not read music data recorded on the optical disk 1 continuously, but performs an intermittent reading operation under the control of the memory controller 6 so that a sufficient amount of music data is always stored in the DRAM 5.

At this time, the speed (transfer rate) of reading music data from the optical disk 1 is higher than the transfer rate of reading music data from the DRAM 5. Specifically, the transfer rate for reading music data from the optical disk 1 and storing it in the DRAM 5 is set to 1.4 Mbit / s,
The transfer rate at which music data is read from M5 is 0.3 Mbit / s, which is about 1/5. Then, the compressed music data is expanded by the audio compression decoder 7 and
The transfer rate when output to the A conversion unit 8 is 1.4M again
bit / s.

This is because, as described above, music data is compressed about five times by the high-efficiency audio compression technique and recorded on the optical disk 1. As a result, the music data read from the optical disc 1
The time difference until the music signal is output from the / A converter 8 is obtained. When the storage capacity of the DRAM 5 is 1 Mbit, music data for about 0.9 seconds can be stored, and the reproduction time of a music signal obtained by expanding and decoding the music data is about 3 seconds. Therefore, even if the reading of the music data from the optical disc 1 is temporarily interrupted, if the reading of the music data from the optical disc 1 can be resumed within about 3 seconds which is the reproduction time of the music data stored in the DRAM 5,
It is possible to avoid interruption of music playback (sound skipping). It is needless to say that this time margin can be increased by increasing the recording capacity of the DRAM 5.

Next, a specific operation of the optical disk reproducing apparatus having the configuration shown in FIG. 1 when performing shuffle reproduction will be described. Here, the configuration of the main part of the conventional optical disc reproducing apparatus will be described with reference to FIG. 1 as being represented by the block diagram shown in FIG.

Prior to the description of the shuffle reproducing operation in the optical disk reproducing apparatus according to the present invention, the shuffle reproducing operation in the conventional optical disk reproducing apparatus will be described with reference to FIGS.
This will be described with reference to FIG. 4, and then the shuffle reproduction operation in the optical disk reproducing apparatus according to the present invention will be described with reference to FIGS.

In the optical disk reproducing apparatus having the configuration shown in FIG. 1, when performing shuffle reproduction, the system controller 13 reads out music data of a tune selected based on a certain shuffle pattern from the optical disk 1 and performs DR conversion.
The control for storing the data in the AM 5 is performed via the memory controller 6. Then, the music data stored in the DRAM 5 is reproduced through the memory controller 6, the music number of the music to be read next from the optical disk 1 is obtained based on the shuffle pattern, and the feed motor 11 is driven to drive the optical pickup 2. The music data of the music is moved to a position where the music data is recorded, and the music data is read out. By repeating this process, shuffle reproduction is performed.

The shuffle pattern used here is:
The reproduction order is selected so that all the songs recorded on the optical disk 1 are always reproduced once at a time. Here, for example, when the shuffle playback of all five songs recorded on the optical disc 1 is performed, the playback order is as shown in Table 1.
Let's say,

First, the music data of the music number 2 reproduced at the beginning of the first round of the shuffle pattern is first stored in the DRAM 5 as shown in FIG. While the music data of the music number 2 is being read out from the DRAM 5 and being reproduced, the system controller 13 calculates the shuffle reproduction order, and as shown in FIG.
The music data of the music number 5 to be reproduced second in the first round is D
Start accumulating in RAM5. After that, the music data of the music number 1 to be reproduced in the first cycle in the same manner as the fifth music data is
Further, music data after the second round of the shuffle pattern is sequentially read from the optical disc 1, stored in the DRAM 5, and reproduced.

[0038]

[Table 1]

However, as shown in FIG.
The reproduction of the music data of the music number 2 reproduced in the second round of the first round of the shuffle pattern stored in the AM5 has not yet been completed, and the music data of the music number 3 which is to be reproduced in the third round of the first round While the DRAM is being stored in the DRAM 5,
If the instruction to reproduce the music data of the next music number 4 is input without reproducing (skip) the music data of the music number 3 which has already started to be stored in the music number 5, the music data of the music number 5 Conventionally, control for discarding (clearing) all music data already stored in the DRAM 5 including music data has been performed. That is, the system controller 13
As shown in FIG. 3B, the music data of the music number 4 is started to be stored without reproducing the music data of the music number 3 to be originally reproduced.
This frequently occurs when the amount of music data of one music is smaller than the storage capacity of the DRAM 5 (the music reproduction time is short).

In order to prevent such a problem, a method is also used in which the order of reproduction of one round of the shuffle pattern is calculated in advance at the start of shuffle reproduction and stored in a storage means such as an SRAM. However, in this method, the calculation time is considerably long, and the memory capacity of the storage means is considerably large in order to be able to store all the reproduction order of up to 255 songs as described above.

There is also a method of calculating the shuffle reproduction order after the input of the skip instruction based on the music number of the music data being reproduced. However, the following problem may occur. That is, as shown in FIG. 4A, in a state where the music data of the music number 1 which is the last music data of the first round of the shuffle pattern stored in the DRAM 5 is being reproduced, the second round of the shuffle pattern is being reproduced. When an instruction to skip the music data of the song number 4 in the second cycle is input when the accumulation of the music data of the song number 4 which is the first music data of the first is started, the system controller 13 proceeds to FIG. As shown in b), the music data of the second song number 2 is read instead of the second song number 1 which is the music data to be read next from the optical disc 1. This is because, although the system controller 13 is reproducing the music data of the song number 1 of the pattern 1 which is the first round of the shuffle pattern, the system controller 13 has already performed the pattern 2 which is the second round of the shuffle pattern at this time. This is because the playback order is calculated. That is,
If the reproduction order is calculated based only on the music numbers of the music data that is actually being reproduced, it is not possible to determine the number of the music number of the shuffle pattern of the music data.

As described above, in the conventional optical disk reproducing apparatus, when performing shuffle reproduction while skipping in the optical disk reproducing apparatus, a desired music piece may not be reproduced in some cases. This is because the data stored in the data storage means such as a DRAM is only the music data read from the optical disk, and management information for managing the stored music data for each song is written together with the music data. Because there is no.

On the other hand, in order to solve such a problem, the optical disk reproducing apparatus according to the present invention has a structure in which the DRAM 5 has a sector structure as shown in FIG. 5, and includes information indicating a shuffle pattern together with music data and the shuffle pattern. The information indicating the determined reproduction order of the music data and shuffle management information are recorded in the header section.

FIG. 6 shows the sector structure of the DRAM 5 shown in FIG. 5 more specifically. That is, the sector structure includes a 4-byte header area in which data management information is recorded, a 2336-byte data area in which music data is recorded, and a SYNC pattern.
It consists of a byte SYNC area.

In the header area, in addition to the management information of the music data recorded in the data area, 1-byte information indicating the shuffle pattern number and 1 indicating the reproduction order determined by the shuffle pattern. Byte information is recorded. If the sector structure of the DRAM 5 is set in this way, the music data to be stored can be managed for each music, so that even when a skip instruction is input, even the music data to be reproduced is cleared. Shuffle reproduction can be performed without any need.

DRAM 5 having sector structure shown in FIG.
The optical disc reproducing apparatus having the configuration shown in FIG.
As shown in FIG. 7A, the music number 2 reproduced second in the first round of the shuffle pattern stored in the DRAM 5
While the reproduction of the music data is not completed yet, the music data of the music number 3 which is to be reproduced in the third round of the first cycle is being stored in the DRAM 5, and the music number which has already started to be stored in the DRAM 5 When the instruction to reproduce the music data of the next music number 4 is input without reproducing (skipping) the music data of music number 3, only the music data of music number 5 already stored in the DRAM 5 Cleared. And
Immediately after the reproduction of the music data of the music number 3 is started and the accumulation of the music data of the music number 3 is completed, the music data of the music number 4 (not shown) to be reproduced next starts to be stored in the DRAM 5.

This is, together with the music data as described above,
Since the information indicating the shuffle pattern number and the information indicating the reproduction order of the music data determined by the shuffle pattern are stored in the DRAM 5 as shuffle management information necessary for the shuffle calculation, the system controller 13 uses the management information. The music data stored in and read from the DRAM 5 can be managed for each music via the memory controller 6 by referring to. Accordingly, no matter when a skip instruction is input, the shuffle management information stored together with the music data being reproduced is replaced with the latest information and the shuffle calculation is performed, so that the shuffle reproduction can be executed correctly.

In the above-described embodiment of the present invention, an optical disk reproducing apparatus for reproducing music data recorded on an optical disk has been described as an example. However, such an optical disk reproducing apparatus stores music data on a recordable optical disk. It may be configured as an optical disk recording / reproducing device also having a recording function. Also, music data has been described as an example of the program recorded on the optical disc 1, but the program may be audio data used for language teaching materials and the like.
More generally, it may be video data or various data recorded as digital signals used in an information processing device such as a personal computer.

[0049]

According to the communication apparatus of the present invention, when a program such as music data read from a randomly accessible recording medium is temporarily stored in a DRAM, a reproduction order pattern specifying the program is specified. Since the information and the information indicating the number of the reproduction order of the pattern are simultaneously stored in the DRAM as shuffle management information, there is no need to provide storage means for storing the shuffle order. Further, it is possible to provide an optical disc reproducing apparatus having a shuffle reproducing function in which a program to be reproduced can be changed at any time.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration example of a main part of an optical disc reproducing apparatus to which the present invention has been applied.

FIG. 2 is a diagram for explaining how music data is stored in a DRAM 5;

FIG. 3 is a diagram for explaining how a plurality of music data are stored in a DRAM 5;

FIG. 4 is a diagram for explaining how a plurality of music data determined by different shuffle patterns are stored in a DRAM 5;

FIG. 5 is a diagram schematically showing a sector structure of a DRAM 5;

FIG. 6 is a diagram showing details of a sector structure of a DRAM 5;

FIG. 7 is a diagram for explaining how music data is stored in a DRAM 5 having the sector structure of FIG. 6;

[Explanation of symbols]

1 optical disk, 2 optical pickup, 3 RF amplifier, 4 EFM & CIRC decoder, 5 DRA
M, 6 memory controller, 7 audio compression decoder, 8 D / A converter, 9 address decoder, 1
0 feed motor, 11 spindle motor, 12
Servo control circuit, 13 System controller, 14
Display, 15 operation keys

Claims (4)

[Claims] 1. A reproduction order pattern generating means for generating a reproduction order pattern in which program numbers for designating all programs recorded on an optical disk without duplication are arranged in a random order, and designated by each program number constituting the reproduction order pattern. Reading means for sequentially reading data of a program to be read from the optical disk; storage means for storing data of the program read by the reading means; and control means for controlling storage and reading operations of the program data in the storage means. A reproducing means for reproducing data of the program read from the storage means; and a program for a program to be read next from the optical disk based on a program number and a reproducing order pattern of the program being reproduced by the reproducing means. An optical disc having selection means for selecting a number. A click reproducing apparatus, the above-mentioned memory means, together with the program data, the optical disk reproducing apparatus in which the program number and to store the information indicating what number of playback sequence pattern. 2. The optical disk according to claim 1, wherein said storage means has a sector structure, and further stores information indicating a reproduction order pattern for designating a reproduction order of said stored program. Playback device. 3. The optical disk reproducing apparatus according to claim 1, wherein said storage means is configured using a DRAM. 4. The optical disc reproducing apparatus according to claim 1, wherein said reproducing order pattern generating means generates a plurality of reproducing order patterns based on a random number sequence.