JPH077580B2 - Data reproducing apparatus and data reproducing method - Google Patents

Description

The present invention relates to a compact disc (hereinafter abbreviated as CD),
Playback that plays media such as digital audio tape (abbreviated as DAT) and optical video discs (abbreviated as LD below) that record audio or images in real time in which data with no time attribute is recorded It relates to the device.

2. Description of the Related Art In recent years, character data is originally recorded on a recording medium for recording data having a time attribute, as represented by a compact disc read only memory (hereinafter abbreviated as CD-ROM) to which a CD is applied. A method for recording data that does not have a time attribute, such as
The playback device is also becoming widespread.

Hereinafter, an example of the above-mentioned data reproducing device will be described.

CD is a recording medium for recording 2-channel audio converted into digital data with a sampling frequency of 44.1 kHz and a quantization bit number of 16, and the transfer rate of audio data during CD playback is
It is 176.4 kbyte / sec. CD-ROM records general digital data such as character data, image data, and computer programs in place of the voice data, and is basically the same as a CD except for the recorded contents. In order to record these data, the CD-ROM has a block structure in the audio data storage area,
It has obtained a transfer rate of te / sec (for example, "Electronics" February 1985 issue, pages 73-80).

Problems to be Solved by the Invention However, in the above-mentioned configuration, since the CD reproducing apparatus is directly applied to the CD-ROM, there is a problem that only a transfer rate of 150 kbyte / sec can be obtained. Taking image data transfer as an example, an image with a gradation of 640 x 480 dots and 8 bits per pixel is 300 kbytes per screen.
The data amount is / sec, and it takes as long as 2 seconds to capture one screen of data.

As a method for increasing the transfer rate of CD-ROM, Japanese Patent Laid-Open No. 59-1
There is 78607 publication. The method disclosed in this publication is a method for minimizing the decrease in the transfer rate of audio data caused by recording video data mixed with audio data by increasing the reproduction linear velocity. To realize this, the reproducing linear velocity is recorded in the disc. However, since the recorded data is required to be reproduced in real time as audio data, this method is used for CD-ROM
When data is recorded on the disk, there is a problem that it cannot be reproduced by a general CD-ROM drive device. That is, this disc cannot be reproduced by a general CD-ROM drive device capable of realizing only a transfer rate of 150 Kbyte / sec, because real-time reproduction of voice cannot be guaranteed unless the disc is reproduced at an increased linear velocity.

The present invention has been made in view of the above problems, and an object thereof is to provide a data reproducing apparatus that does not require a dedicated recording medium and realizes a high transfer rate as needed.

Means for Solving the Problems In order to achieve the above object, the data reproducing apparatus of the present invention comprises:
Reproduction means for reproducing a recording medium on which data and control information are recorded and outputting a reproduction signal, separation means for separating the reproduction signal into control information and data and outputting the same, processing output means for processing and outputting the data, and control Using the information, it is judged whether or not the real time property is required for the reproduction of the data in the recording medium, and if the real time property is not required, the reproducing means for reproducing the recording medium at a higher speed than when it is required. Is provided with control means for controlling.

Effect The present invention has the above-described configuration and can reproduce data at a high transfer rate when real-time property is not required for data reproduction.

Embodiment Hereinafter, a data reproducing apparatus according to an embodiment of the present invention will be described with reference to FIGS. 1, 2, and 3. In this embodiment, a CD-ROM is used as the recording medium. FIG. 1 is a schematic block diagram of a data reproducing device according to an embodiment of the present invention, FIG. 2 is a detailed block diagram of the data reproducing device of FIG. 1, and FIG. 3 is a schematic diagram of a data format of a CD or a CD-ROM. Is.

First, the data format of the CD-ROM will be described with reference to FIG.

In FIG. 3, (a) is a schematic diagram of a data frame which is the minimum unit of recording, (b) is a schematic diagram of a subcode frame, (c) is a schematic diagram of a Q channel data format in the lead-in area, ( d) is a schematic diagram of the data format of the Q channel in the program area. The CD has a lead-in area, a program area, and a lead-out area indicating the end of the disk from the inner circumference to the outer circumference of the disk, and the actual data is recorded in the program area. Audio data is also recorded on the CD in the same data format as in FIG.

There are a sub channel 2 and a main channel 1 in one data frame, which are recorded on a CD-ROM in a time division manner. The sub-channel 2 has a 1-byte data recording area, and the main channel 1 has a 24-byte data 3 and 8-byte error detection and correction code 4 data recording area of 32 bytes in total.

In CD, 2-channel audio data quantized with a sampling frequency of 44.1 kHz and a quantization bit number of 16 bits (hereinafter, this data is abbreviated as CD-DA data) is recorded at the position of data 3. Therefore, the data frame rate
44.1k x (16/8) x 2/24 = 7350 data frames / sec. In the CD-ROM, general digital data having a block structure is recorded in this area. The block structuring method will be described later. The error detection / correction code 4 is a code for detecting and correcting a data error of the data of the main channel 1, and is not for the sub-channel 2.
The method of creating the error detection and correction code 4 is the same for the CD and the CD-ROM.

Before recording these data on a CD-ROM, EFM (Eigh
t-to-Fourteen-Modulation) modulation, addition of a data frame synchronization signal for identifying the boundaries of data frames, and the like are performed. As a result, one data frame is 58
It becomes 8 bits, and the bit rate when recorded on a CD-ROM is 580 x 7350 = 4.3218 Mbit / sec. This data is NRZ
It is recorded in the i signal format at a constant speed (about 1.25 m / sec).

A subcode frame is formed by subchannel 2 for 98 consecutive data frames. There are 75 subcode frames per second. This is shown in FIG. 3 (b). The sub-channel 2 for the first two data frames constitutes the sub-code frame synchronization 7, and the sub-channel 2 for the remaining 96 data frames records data called sub-code. Each bit of 1 byte of the subcode corresponds to a channel, and these channels are called P channel, Q channel, ..., W channel.

P channel 8 is a track (normally one track is one for CD
(Corresponding to a piece of music), the flag is set to 1 for 2 seconds or more before each track starts in the program area. In the lead-out area, 1 and 0
Is repeated in a cycle of 2 seconds.

Search information for performing a search in the disc is recorded in the Q channel 9.

An address is recorded as search information in the Q channel 9 of the program area (see FIG. 3 (d)). For the address, the absolute time (AMIN, ASE
C, AFRAME), the relative time (MIN, SEC, FRAME) that sets the beginning of each track to 0 minutes 0 seconds 0 frame, the track number, and the index, and each is a BCD code (2
It is recorded in the evolutionary decimal number). The frame here is a unit of time, and 75 frames correspond to 1 second. That is, the frame as a unit of time is equal to the time length of one subcode frame. The track number is fixed at 00 in the lead-in area and AA (hexadecimal display) in the lead-out area. In the program area, the track number can take values from 01 to 99. The control recorded at the beginning of the Q channel 9 is 4-bit control information. This value has the same value in one track of the program area.
Specifically, the following values are recorded.

00 × 0… 2-channel audio, without emphasis 00 × 1… 2-channel audio, with emphasis 01 × 0… Data track ×× 0 ×… Digital copy prohibited ×× 1 ×… Digital copy allowed (where x is 0 or 1 ) (00x0) and (00x1) are recorded on the CD. On the other hand, (01 × 0) is recorded on the CD-ROM. However, C
Even with D-ROM discs, tracks on which CD-DA data is recorded (hereinafter abbreviated as CD-DA tracks) can be provided, and these tracks are used as controls (00x
0) and (00 × 1) are recorded. That is, CD-RO
In the M, a disc consisting of only a track (hereinafter abbreviated as a CD-ROM track) on which general digital data having a block structure is recorded in the area of the data 3, and a CD-ROM
Some discs have both tracks and CD-DA tracks.

In the Q channel 9 of the lead-in area, information regarding the arrangement of the program area and the lead-out area is recorded as search information. This information is TOC (Table of contents)
In the program area, the absolute time at the beginning of each track and the control information of each track, the first and last track numbers of the program area, and the absolute start time of the lead-out area are recorded.

Hereinafter, a specific TOC recording method will be described with reference to FIG. This figure schematically shows the data structure of 96 bits in one subcode frame of the Q channel in the lead-in area. (0001) is recorded in the ADR from bit 4 to bit 7. In the track number, 00, which is the track number of the lead-in area, is recorded. MIN, SEC and FRAME indicate the relative time in the lead-in area in minutes, seconds and frames, respectively. 0 is recorded in 8 bits from bit 48. CRC (Cyclic Redundancy Check) code for error detection is recorded in 16 bits from bit 80. Control, point, PMIN, PSE
TOC is recorded using C and PFRAME. If the point is a BCD code with a value from 01 to 99, PMIN, PSEC, PFRA
The absolute start time of the track, which is indicated by points in ME,
Minutes, seconds, and frames are recorded respectively, and the control information of the track indicated by points is recorded in the control. For example, if the points, PMIN, PSEC, PFRAME, and control are 09,43,20,24,4 (0100), the 9th track starts at 43 minutes 20 seconds 24 frames in absolute time.
-Indicates that it is a ROM track. The point is A0
In the case of (hexadecimal display), 01, which is the track number of the first music track of the CD, is recorded in PMIN. At this time, 00 is recorded in PSEC and PFRAME. The point is A1
If it is (hexadecimal display), the track number of the last music track of the disc is recorded in PMIN. At this time, 00 is recorded in PSEC and PFRAME. The point is A2 (1
In hexadecimal notation, the start address of the lead-out area is recorded in PMIN, PSEC, and PFRAME in absolute time. This TOC is repeatedly recorded in the lead-in area,
Also, the same content is recorded in three consecutive subcode frames.

The 6 channels from the R channel to the W channel are handled in a unified manner. The CD graphic karaoke apparatus sold in the commercial field records graphic data on these channels.

Next, how the CD-ROM disc described above is reproduced by the data reproducing apparatus of the present invention will be described with reference to FIG.

In FIG. 1, 50 is a CD-ROM, 51 is a reproducing means for reproducing a CD-ROM and outputting data and control information, 52 is a separating means for separating data and control information, and 53 is for processing and outputting data. Processing output means, 54 inputs control information and re-output means 51
Is a control means for controlling.

The CD-ROM 50 is a CD on which the above-mentioned characters and image data are recorded.
-ROM tracks (first and second tracks) and CD-DA tracks (third to tenth tracks) on which audio is recorded are mixed.

First, when the CD-ROM 50 is set in the reproducing means 51, the control means 54 controls the reproducing means 51 to reproduce the lead-in area of the CD-ROM 50. The reproducing means 51 reproduces the lead-in area, and the separating means 52 detects the data frame synchronization from the reproduced signal output from the reproducing means 51 and separates the main channel 1 and the sub-channel 2. The data of the Q channel 9 included in the sub channel 2 is sent to the control means 54. The control means 54 is the TOC recorded in the Q channel 9.
Is stored in the internal memory. As described above, the TOC includes the absolute time at the beginning of each track, control information of each track, and the like, and hence the control means 54 controls the reproduction means 51 from the input means (not shown). It is possible to reproduce any position on the designated CD-ROM 50.

When the control means 54 is instructed to reproduce the fifth track from the outside, the control means 54 selects from the TOC stored in the internal memory,
The absolute time at the beginning of the fifth track and the control information of the fifth track are obtained. The control means 54 converts the absolute time into a physical position on the CD-ROM 50, moves a pickup (not shown) in the reproducing means 51 to that position, and instructs the reproducing means 51 to reproduce. The control means 54 indicates from the control information that the fifth track is CD-DA.
Knowing that this is a track, CD-DA tracks require real-time playback of data, so this playback is approximately 1.25 m / sec.
At a linear velocity of. When this reproduction is started, the CD-DA data is sent to the processing output means 53 at a data rate of 176.4 kbyte / sec. In the processing output means 53, the sent CD-DA
The data is converted into a 2-channel analog audio signal and output to the outside.

Even when the controller 54 is instructed to reproduce the second track from the outside, the controller 54 similarly stores the TOC stored in the internal memory.
From among these, the absolute time at the beginning of the second track and the control information for the second track are obtained. The control means 54 displays the absolute time on the CD-ROM 5
The physical position is changed to 0, and a pickup (not shown) in the reproducing means 51 is moved to that position to instruct the reproducing means 51 to reproduce. The control means 54 knows from the control information that the second track is the CD-ROM track. Since the CD-ROM track generally records data having no time attribute, such as character data and computer programs, this reproduction is performed at a linear velocity higher than 1.25 m / sec. For example,
Approximately 300kby to the processing output means 53 when the playback speed is doubled
Data is sent at high speed with a transfer rate of te / sec.

Next, the operation of the data reproducing apparatus of FIG. 1 described above will be described in more detail with reference to FIG.

FIG. 2 is a detailed block diagram of the data reproducing apparatus of FIG.

In FIG. 2, 60 is the same CD-ROM as CD-ROM 50,
The first and second tracks are CD-ROM tracks, the third track
It is assumed that tracks 10 to 10 are CD-DA tracks. 61 is a spindle motor for rotating the CD-ROM 60, 62
Is a pickup that reads a signal from the CD-ROM 60, 63 is a waveform shaping circuit that shapes the analog signal output from the pickup 62 into a pulse signal, 64 is a synchronization detection circuit that detects data frame synchronization or subcode frame synchronization 7, and 65 is
EFM demodulation circuit, 66 is an error detection and correction circuit that performs error detection and correction of main channel 1 using error detection and correction code 4,
67 is a RAM, 68 is a microprocessor, 69 is a CD-ROM signal processing circuit, 70 is RAM, 71 is a microprocessor, 72 is a switch circuit, 73 is a DA conversion circuit, and 74 is an interface circuit. Reference numeral 75 is a clock generation circuit, which sends a reference clock to the servo circuit 77 and the error detection / correction circuit 66, sends a master clock to the microprocessors 68 and 71, and sends a CD-RO.
M signal processing circuit 69, interface circuit 74, DA conversion circuit 7
The clock required for operation 3 is output. 76 is a personal computer, 77 is a CLV (Constant Linear Velocity) servo that controls the rotation of the spindle motor 61, CD-ROM
Focus servo that focuses the reading laser light on 60, tracking servo that makes the reading laser light follow the track spirally formed on the CD-ROM 60,
Reference numeral 78 denotes a clock extraction circuit for performing a traverse servo for moving the pickup 62 to the inner and outer circumferences.

The reproducing means 51 includes a motor 61, a pickup 62, and a waveform shaping circuit.
63, sync detection circuit 64, clock extraction circuit 78, servo circuit 77
Consists of. The separating means 52 includes an EFM demodulation circuit 65, an error detection / correction circuit 66, a RAM 67, a CD-ROM signal processing circuit 69, a RAM 70, an interface circuit 74, and a switch circuit 72. Processing output means 5
3 includes a DA conversion circuit 73 and a personal computer 76. The control means 54 includes a microprocessor 68, a microprocessor 71, a clock generation circuit 75, and an interface circuit 74.
Consists of.

First, when the CD-ROM 60 is set in the spindle motor 61, the microprocessor 68 controls the servo circuit 77 and
-Play the lead-in area of ROM60. That is, the microprocessor 68 uses the servo circuit 77 to move the pickup 62 to the lead-in area, and then rotates the spindle motor 61 to apply focus servo and tracking servo of the pickup 62. Since the signal read by the pickup 62 is an analog signal, the waveform shaping circuit
After being converted into a pulse signal in 63, it is sent to the synchronization detection circuit 64 and the clock extraction circuit 78. The clock extraction circuit 78 is a PLL
It has a built-in circuit and creates a clock (hereinafter, this clock is abbreviated as a reproduction clock) necessary for punching data from the input pulse signal. The synchronization detection circuit 64 latches the input pulse signal with the reproduction clock, detects the data frame synchronization and the subcode frame synchronization,
It is sent to the EFM demodulation circuit 65 and the error detection and correction circuit 66. The EFM demodulation circuit 65 performs EFM demodulation and at the same time the main channel 1
And sub-channel 2 are separated. Main channel 1
Data is sent to the error detection / correction circuit 66 in the next stage. Of the subchannel 2 data, the Q channel 9 data is CR
After error detection is performed using C, error free data is sent to the microprocessor 68. Microprocessor
68 stores the TOC included in the input Q channel 9 data in an internal memory (not shown). The control information in the TOC allows the microprocessor 68 to know that the first and second tracks of the CD-ROM 60 are CD-ROM tracks, and the third to tenth tracks are CD-DA tracks.

When the personal computer 76 instructs the microprocessor 68 via the interface circuit 74 and the microprocessor 71 to reproduce the fifth track, the microprocessor
68 obtains the absolute time at the beginning of the fifth track and the control information of the fifth track from the TOC stored in the internal memory. The microprocessor 68 converts the absolute time into a physical position on the CD-ROM 60, moves the pickup 62 to that position via the servo circuit 77, and instructs reproduction. The following procedure is taken until the actual reproduction of the fifth track is started. First, the microprocessor 68 moves the pickup 62 to an approximate position calculated from the absolute time and performs reproduction. The EFM demodulation circuit 65 extracts the data of the Q channel 9 from the reproduced signal, and the absolute time contained in this is compared with the absolute time of the beginning of the fifth track in the TOC. If they are different, the microprocessor 68 moves the playback position by moving the pickup 62 or performing a track jump. This operation is repeated until the reproduction position reaches the beginning of the fifth track.

Playback is started by moving to the beginning of the fifth track. The microprocessor 68 knows from the control information that the fifth track is the CD-DA track. Since CD-DA tracks require real-time data playback, this playback is about 1.
It is performed at a linear velocity of 25 m / sec. Microprocessor 68 directs clock generation circuit 75 to generate a 4.3218 MHz reference clock. This reference clock is the servo circuit 77
Is sent to the error detection and correction circuit 66. In the servo circuit 77, the spindle motor is adjusted so that the reproduction clock sent from the clock extraction circuit 78 and the reference clock have the same frequency.
61 rotation control is performed. On the other hand, the error detection / correction circuit 66 performs error detection / correction of the main channel 1 according to the reference clock, and outputs CD-DA data at a data rate of 176.4 Kbyte / sec.

Main channel 1 sent to the error detection and correction circuit 66
Data is synchronized with the reproduction clock, and the reproduction clock contains jitter, so the jitter is corrected using the RAM 67. The RAM 67 is also used as a data buffer at the time of error detection and correction. Clock extraction circuit 78
The built-in PLL circuit contains two voltage controlled oscillators with center frequencies of 4.3218MHz and 8.6436MHz, and they are configured to be used by switching. This switching is performed by the microprocessor 68. When real-time property is required for data reproduction such as CD-DA track, 4.3218MHz voltage controlled oscillator is used. The microprocessor 68 turns on the switch circuit 72, and the CD-DA data output from the error detection / correction circuit 66 passes through the switch circuit 72 and the DA conversion circuit.
At 73, it is converted into an analog audio signal and output to the outside.
The microprocessor 71 receives the status information from the microprocessor 68 and knows that the CD-DA reproduction is performed,
The operation of the CD-ROM signal processing circuit 69 is stopped.

Even when the personal computer 76 instructs the microprocessor 68 via the interface circuit 74 and the microprocessor 71 to reproduce the second track, the microprocessor 68 similarly selects the second from the TOCs stored in the internal memory.
The absolute time at the beginning of the track and the control information for the second track are obtained. The microprocessor 68 stores the absolute time in the CD-ROM6.
The physical position is converted to 0, and the second track is accessed and reproduction is started in the same procedure as when accessing the fifth track. The microprocessor 68 knows from the control information that the second track is the CD-ROM track. Since the CD-ROM track is recorded with character data and data that generally has no time attribute, such as a computer program, this reproduction raises the linear velocity from 1.25 m / sec to about 2.5 m / se.
done in c. Specifically, the procedure is as follows. The microprocessor 8 instructs the clock generation circuit 75 to generate a reference clock of 8.6436 MHz, and also switches the voltage controlled oscillator in the clock extraction circuit 78 to an oscillator having a center frequency of 8.6436 MHz.

The servo circuit 77 controls the rotation of the spindle motor 61 so that the reproduction clock sent from the clock extraction circuit 78 and the reference clock have the same frequency. Therefore,
The CD-ROM 60 is rotated at twice the linear velocity of the CD-DA track. On the other hand, the error detection / correction circuit 66 performs the error detection / correction of the main channel 1 in accordance with the reference clock.
Outputs data at a data rate of 2.8 Kbyte / sec. The microprocessor 68 turns off the switch circuit 72, and the CD
-Prevent DA data from being output as sound via the DA conversion circuit 73 by mistake. The microprocessor 71 receives the status information from the microprocessor 68, knows that the output of the error detection / correction circuit 66 is the data of the CD-ROM having the block structure, and operates the CD-ROM signal processing circuit 69. The CD-ROM signal processing circuit 69 performs error detection and correction of the CD-ROM, and the data is sent to the personal computer 76 through the interface circuit 74 at a transfer rate of 300 Kbyte / sec. The personal computer 76 receives the data and outputs images and characters.

In the above-described embodiments, the CD-ROM tracks are not required to have real-time data reproduction.

Next, as a second embodiment, a case of reproducing a CD-ROM track on which data for which real-time reproduction is required is recorded will be described with reference to FIGS. 2 and 4.

FIG. 4 is a schematic diagram of a data format recorded in the main channel of the CD-ROM.

First, the format of data recorded in the main channel 1 will be described with reference to FIG. FIG. 4 (a) is a schematic diagram of the data format of the sector of CD-ROM mode 1, FIG. 4 (b) is a schematic diagram of the data format of the sector of CD-ROM mode 2 form, and FIG. 4 (c).
Is a schematic diagram of the data format of the sector of CD-ROM mode 2 form 2, FIG. 4 (d) is a schematic diagram showing the recorded contents of the sub-header, and FIG. 4 (e) is a schematic diagram of the sub-mode byte.

In the main channel 1 of one data frame, 24 bytes of data are recorded as shown in FIG. Data of 98 data frames for CD-ROM track 2
Structuring is performed with 352 bytes as one sector. The length of one sector corresponds to the length of one subcode frame. Each sector has a 12
There is a byte sync signal, followed by a 4-byte header. The first 3 bytes of the header are called a physical sector address, and an absolute address in which the beginning of the program area is 0 minute 0 second 0 sector is recorded. This absolute address is the absolute time (AMIN, ASEC,
AFRAME) is the same value. The last byte of the header indicates the mode, and the recorded contents of the remaining 2336 bytes differ depending on this value. In mode 0, the remaining 2336 bytes are all 0. Mode 1 is 20 as shown in Fig. 4 (a).
After 48 bytes of user data, 4 bytes of error detection code, 8 bytes of 0 data, and 276 bytes of error correction code are added. In mode 2, an 8-byte subheader is provided following the header. The subheader is shown in Fig. 4 (d).
As shown in, the 4 bytes of the file number, channel number, submode, and coding information are recorded twice from the beginning. The submode is bit-encoded as shown in FIG. Bit 5 of the sub mode is called a form bit, and the format of 2328 bytes after the sub header differs depending on the value of this bit. A sector whose form bit is 0 is called a form 1 sector, and its data structure has 2048 bytes of user data, 4 bytes of error detection code, and 276 bytes of error correction code added after the subheader (fourth See FIG. (B)). On the other hand, a sector in which the form bit is 1 is called a form 2 sector, and its data structure has 2324 bytes of user data and a 4-byte reserved area added after the subheader (see FIG. 4 (c)). Bit 6 of the sub-mode is called a real-time sector bit, and is an example of control information for determining whether or not real-time property is required for reproducing the data of the CD-ROM track. A sector in which this bit is 1 is called a real-time sector, and a file including this sector has a time attribute and must be reproduced in real time. For example, if you try to play audio and images for a long time at the same time,
It is necessary to read out the image data at the same time as reading out the audio data from the recording medium. In general, in order to realize this, the time-axis-compressed audio recorded sector and the image data recorded sector are time-axis multiplexed and recorded. During reproduction, when the processing output means 53 receives the sector in which the compressed audio data is recorded from the separating means 52, the compressed audio data is accumulated in the buffer in the processing output means 53, and at the same time, the compressed audio data is decoded and converted into audio. Output. Further, when the sector in which the image data is recorded is being received, the operation of writing the image data in the image memory is performed while decoding the compressed audio data stored in the buffer. When considering such applications, CD
-Real-time performance is required for data reproduction even in the ROM track.

Next, how the disc is reproduced by the data reproducing apparatus of FIG. 2 will be described. In the CD-ROM 60, the first and second tracks are CD-ROM tracks, and the third to tenth tracks are CD-DA tracks, as in the first embodiment. Further, it is assumed that the CD-ROM track has recorded therein data that requires real time reproduction and data that does not require real time reproduction.

The operation of reading the TOC and the reproduction of the CD-DA track are the same as those in the first embodiment, and the description thereof will be omitted.

In the first embodiment, the description will be made by specifying the track number and CD-
Although it has been described that the ROM 60 is reproduced, the case where the logical sector address is designated from the personal computer 76 will be described in the present embodiment. Physical sector address is 0
A sector of minute 2 seconds 0 sector corresponds to address 0 of the logical sector address.

From the personal computer 76, for example logical address 12
When it is transmitted to the microprocessor 71 through the interface circuit 74 so as to reproduce the data of 4500 sectors from the address 000, the microprocessor 71 causes the logical address (1200
Address 0) is converted to a physical address (2 minutes 42 seconds 0 sector). This physical address is communicated to microprocessor 68. The microprocessor 68 learns from the TOC read from the disc that the reproduction position is the CD-ROM track, and informs the microprocessor 71 as status information. Microprocessor 71 receives this and CD-ROM
A physical address is set in an address register (not shown) in the signal processing circuit 69.

Microprocessor 68 has a specified playback position on CD-ROM
Since it is a truck, at 2.5m / sec as in the first embodiment
Play the CD-ROM60. As a result, the error detection and correction circuit 6
6 performs error detection and correction of main channel 1, 352.8Kb
CD-ROM signal processing circuit for data at yte / sec data rate
Send to 69.

In the CD-ROM signal processing circuit 69, first, a 12-byte sync signal is detected, and following the sync signal, a match between the physical sector address recorded in the header and the content of the address register is detected. After the address match is confirmed, the mode byte is checked, and if it is mode 1, error detection and correction of the CD-ROM is performed, and the total data of 4500 sectors is 300 Kbytes in the personal computer 76 via the interface circuit 74. Sent at a transfer rate of / sec. On the other hand, if the sector is in mode 2, the subheader is sent to the microprocessor 71 and the real-time sector bit of the submode byte is checked. If this bit is 0, reproduction is continued at the same speed. When this bit is 1, it is necessary to reproduce at the normal reproduction speed, so that the microprocessor 71 operates the CD-ROM signal processing circuit 69.
Then, the microprocessor 68 is instructed to resume the reproduction at the normal reproduction speed. The microprocessor 68 suspends the reproduction according to the instruction and controls the clock generation circuit 75, the servo circuit 77, and the clock extraction circuit 78 to restart the reproduction at the linear velocity of 1.25 m / sec.

As described above, according to the present embodiment, the data reproducing apparatus of the invention reproduces the recording medium on which the data and the control information are recorded and outputs the reproduction signal, and separates the reproduction signal into the control information and the data. Separation means for outputting, processing output means for processing and outputting data, and control information is used to judge whether or not real-time property is required for reproduction of data in the recording medium,
By providing a control means for controlling the reproducing means so as to reproduce the recording medium at a higher speed than the case where the real-time property is not required, it is possible to improve the high-performance when the data reproduction is not required. Data can be played back at the transfer rate.

In the above embodiment, two types of voltage controlled oscillators are provided in the PLL circuit inside the clock extraction circuit 78 and switched to use, but the clock extraction circuit may be realized by a PLL circuit having a wide pull-in range. By doing so, high-speed reproduction can be realized at an arbitrary reproduction speed. If an arbitrary reproduction speed can be realized, the reproduction speed can be set by judging the processing capacity of the processing output means 53, or the reproduction speed can be increased or decreased according to the request from the processing output means 53.

Further, in the second embodiment, the control information is read by the microprocessor 68 or the microprocessor 71 to determine the reproduction speed, but the control information is sent to the personal computer 76 so that the reproduction speed can be specified from the personal computer. It is also possible. In this case, the personal computer 76 realizes not only the function as the processing output means 53 but also a part of the functions of the control means 54.

Further, although the control information is recorded in the area other than the user data such as the sub-channel and the sub-header in the second embodiment, the recording position of the control information is not limited to this.
It is also possible to record in the user data. For example, the control information may be recorded in the user data area as a part of the directory information indicating the arrangement of data in the recording medium. In this case, the directory information is read into the personal computer prior to the data reproduction, and the reproduction speed is designated by the personal computer. It is also possible to incorporate the control information in a part of the application program executed by the personal computer instead of the directory information. In this case,
The personal computer executes the application program to specify the reproduction speed. There are various methods for incorporating the control information into the application program and the directory information. When incorporating as directory information, a flag indicating a non-real-time file or a real-time file may be provided in the attribute of each file. In addition, when incorporating into an application program, both the method for the application program to specify the playback speed using a function call, and the function call when real-time playback is required and when it is not required. Various methods may be considered, such as a method in which an application program is provided and data is reproduced by selecting one of them.
In this case, the personal computer 76 not only functions as the processing output means 53, but also the control means 54 and the separation means 52.
Some functions of will also be realized.

Further, in the above embodiment, the microprocessor 68 determines the reproduction speed by using the control information in the TOC, but the control of the Q channel which is the control information recorded in the program area may be used. In this case, the reproduction may be performed at the normal speed for the time being, and the reproduction speed may be gradually increased after it is determined that the real time property is not required.

In addition, a switch that can be switched from the outside is provided in the data reproducing device to switch between normal mode and high speed mode
The control means is such that the switch indicates the high speed mode, and
The recording medium may be reproduced at high speed only when real-time property is not required for reproducing the data. In this case, the state of this switch is read by the microprocessor 68 or the microprocessor 71.

Further, in the above embodiment, the CD-ROM is described as an example, but the recording medium is not limited to this, and for example, DAT, LD-RO.
Any recording medium such as M can be used as long as the recording medium can continuously read data at a predetermined transfer rate.

EFFECTS OF THE INVENTION As described above, the present invention includes a reproducing unit that reproduces a recording medium on which data and control information are recorded and outputs a reproduction signal, and a separation unit that separates and outputs the reproduction signal into control information and data.
A processing output means for processing and outputting data and a control information are used to judge whether or not the reproduction of the data in the recording medium requires real-time processing. By providing a control means for controlling the reproducing means so as to reproduce the recording medium at a higher speed, it is not necessary to change the method of recording data on the dedicated recording medium, and a high transfer rate can be set as necessary during reproduction. It is possible to realize a realized data reproducing device. That is, when real-time property is not required for data reproduction, it is possible to reproduce data at a high transfer rate.

Further, when the processing output means specifies the reproduction speed to the control means when the real-time property is not required for the reproduction of the data, the recording medium is reproduced at the transfer rate optimum to the processing capacity of the processing output means. A data reproducing device can be realized.

In addition, a switch that can be switched from the outside is provided in the data reproducing device to switch between normal mode and high speed mode
The control means is such that the switch indicates the high speed mode, and
If the recording medium is reproduced at high speed only when the real-time property is not required for reproducing the data, the versatility of the reproducing device can be improved.

[Brief description of drawings]

FIG. 1 is a schematic block diagram of a data reproducing device according to an embodiment of the present invention, FIG. 2 is a detailed block diagram of the data reproducing device of FIG. 1, and FIG. 3 is a schematic diagram of a data format of a CD or a CD-ROM. FIG. 4 is a schematic diagram of a data format recorded in the main channel of the CD-ROM. 50 …… CD-ROM, 51 …… Playback means, 52 …… Separation means, 53
...... Processing output means, 54 ...... control means.

Claims (8)

[Claims] 1. A reproducing means for reproducing a recording medium on which data and control information of the data are recorded and outputting a reproduction signal, and a separating means for inputting the reproduction signal and separating and outputting control information and data. A processing output unit that processes and outputs the data output from the separation unit, and a control information output from the separation unit is used to determine whether real-time property is required for reproducing the data in the recording medium. If the real-time property is not required, the data reproducing apparatus is characterized by comprising control means for controlling the reproducing means so as to reproduce the recording medium at a higher speed than when it is required. 2. A recording medium having a disk shape, and control information and data are recorded on tracks formed concentrically or spirally at a constant angular velocity or a constant linear velocity, thereby increasing the reproduction angular velocity or the reproduction linear velocity. The data reproducing apparatus according to claim 1, wherein the recording medium is reproduced at high speed by means of this. 3. The control means controls the reproducing means so as to reproduce the recording medium at the reproduction speed designated by the processing output means when the real time property is not required for reproducing the data. 1. The data reproducing device according to 1. 4. A mode changeover switch for switching between a normal mode and a high speed mode from the outside, wherein the control means indicates that the operation mode changeover switch indicates the high speed mode, and data reproduction requires real-time performance. 2. The data reproducing apparatus according to claim 1, wherein the reproducing means is controlled so as to reproduce the recording medium at high speed only when the data is not reproduced. 5. When reproducing at least a recording medium on which data and control information for the data are recorded, is it required to reproduce the data recorded in the recording medium by using the control information in real time? A data reproducing method, characterized in that the recording medium is reproduced at a higher speed than the case where the real-time property is not required. 6. A recording medium having a disk shape, and control information and data are recorded on a track formed in a concentric circle shape or a spiral shape at a constant angular velocity or a constant linear velocity to increase the reproduction angular velocity or the reproduction linear velocity. 6. The data reproducing method according to claim 5, wherein the recording medium is reproduced at high speed. 7. The data reproducing method according to claim 5, wherein when the data is not required to be reproduced in real time, the recording medium is reproduced at a reproduction speed capable of processing and outputting the data. 8. A recording medium at high speed only when a mode changeover switch provided in a reproducing device for switching between a normal mode and a high speed mode indicates a high speed mode, and real time property is not required for data reproduction. 6. The data reproducing method according to claim 5, wherein the data is reproduced.