JP2003196926A - Information reproducing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the reproduction performance of an information recording medium. <P>SOLUTION: A system controller 21, when executing a reproduction command from a host computer 2 while buffering data of an optical disk 3, obtains the reproduction position out of the reproduction command and, when the rotation time calculated out from the last position and the reproduction position of the information being buffered is within the threshold value, makes a pickup wait for the rotation of the optical disk instead of seeking the optical disk and reproduces the data from the position on the optical disk based on the reproduction position to process buffering. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to information reproduction for reproducing information on an information recording medium such as a CD-ROM disc, a CD-R / RW disc, a DVD-ROM disc, a DVD-RAM disc and a DVD-RW disc. Regarding the device.

[0002]

2. Description of the Related Art In recent years, CD-ROM / CD-R / CD-
In the information reproducing apparatus such as the RW drive and the DVD-ROM drive, the rotation speed of the information recording medium such as the CD-ROM disc, the CD-R / RW disc, the DVD-ROM disc, the DVD-RAM disc, the DVD-RW disc is high. Speed and seek time, and the host interface (H
There is a movement to improve reproduction performance by speeding up data transfer on the ost I / F). The rotation speed is, for example, 40 when reproducing the CD-ROM drive.
Some are more than double. In this way, it is an attempt to improve the access speed to the information recording medium and bring it closer to the performance of the hard disk drive (HDD).

For example, in a CD-ROM drive, the average access time (1 sector reproduction of a random address) has come to reach 80 ms. This is possible because the weight of pickups has been reduced. In addition, in the ATAPI which is a kind of host interface between the information reproducing apparatus and the host computer, the Ult
High-speed DMA transfer called ra DMA has become mainstream,
A transfer rate of 100 MB / S has become possible. As described above, generally, physical methods are used to speed up access to the information recording medium.

Assuming that the CD-at a playback speed of 40X (double speed)
If the ROM disk is rotating, the 1x speed of the CD-ROM disk is a transfer rate of 150 KB / S.
At 40 times speed, the transfer rate is 6000 KB (6 MB) per second, and the processing time per sector is 330 μS. Therefore, if the difference between the current position (Y) of the pickup and the reproduction request address (target reproduction position (X)) from the host computer is 20 sectors, the rotation waiting time of 20 sectors is 20 * 330 (μs) = It will be 6.6 ms.

However, if seek is performed from the current position (Y) of the pickup to the target reproduction position (X), it may take about 10 ms. Further, when a CD-ROM disc having poor recording quality is used, a seek retry occurs, and seek takes an extra time. Therefore, conventionally, regarding the pre-reading process of the information recording medium and the execution of the playback command from the host computer during the pre-reading, when the address consecutive to the playback address at the time of the previous command is the next playback address, the information to continue the pre-reading A reproducing apparatus (see, for example, Japanese Patent Laid-Open No. 5-135483) has been proposed.

[0006]

However, if the information on the information recording medium is not continuous, prefetching (buffering) is not performed. Therefore, if non-continuous addresses are requested, a seek is performed and performance is increased. There was a problem that it decreased. The present invention has been made to solve the above problems, and an object thereof is to improve the reproduction performance of an information recording medium.

[0007]

In order to achieve the above object, the present invention provides a stamp disc or a disc in which information is recorded by an information recording device at a plurality of types of rotation speeds based on a reproduction command from a host computer. In an information reproducing apparatus that rotates an information recording medium and reproduces information on the information recording medium, when a reproducing command from the host computer is executed, a reproducing position is obtained from the reproducing command and the information recording is performed. When the rotation time calculated from the final position of the information that is reproduced from the medium and buffered and the reproduction position is within a predetermined time, the information recording medium is not sought to seek and the reproduction is performed. A buffering means for reproducing information from the position on the information recording medium based on the position and performing a buffering process is provided.

In the information reproducing apparatus as described above, it is preferable to provide a control means for controlling the buffering process by the buffering means so as to be performed only while reproducing from the information recording medium. further,
In the information reproducing apparatus as described above, it is preferable to provide means for setting the predetermined time so as to be different depending on the rotation speed of the information recording medium. Furthermore, in the information reproducing apparatus as described above, when there is a packet or track joint between the last buffered position on the information recording medium and the reproducing position, the rotation waiting is prohibited. It is advisable to provide a means for performing a seek by directly seeking to the playback position of the information recording medium.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a CD-R / RW drive device according to an embodiment of the present invention. This CD-R / RW drive device 1
Is communicably connected to the host computer 2 via an interface (I / F) 26 such as ATAPI,
Based on a reproduction command from the host computer 2, the stamp disc or the optical disc 3 which is an information recording medium on which information (data) is recorded by the information recording device is rotated at a plurality of types of rotation speeds, and the data on the optical disc 3 is recorded. This is an information reproducing device for reproducing.

The CPU 11 is a user micro controller (User Micro Controller).
1), which is a central processing LSI for controlling all operations of the CD-R / RW drive device 1. Flash R
The OM (Flash ROM) 12 is a non-volatile memory that can be erased or rewritten by the CPU 11.
Stores a control program for performing various control processes. Host interface controller (HOST I
The / F CONTROLLER 13 is an LSD that controls data communication between the host computer 2 and the CD-R / RW drive device 1.

Buffer Manager (BUFFER MA
(NAGER) 14 is an LSI that controls transfer of data transferred from the host computer 2 and data read from the optical disk 3. The DRAM 15 is a buffer memory that temporarily stores (buffers) the transfer data from the host computer 2 and the data read from the optical disc 3. The buffering means the optical disc 3
Data is temporarily stored instead of being transferred to the host computer 2, and is reproduced and buffered as long as there is a free space in the DRAM 15. Subcode operation controller (SUB CODE
The OPERATION CONTROLLER 16 generates a subcode to be recorded on the optical disc 3 and separates the subcode read from the optical disc 3 (SUB).
(P, Q, R, ..., W).

CD-ROM encoder (CD-ROM
The ENCODER 17 is an LSI that modulates the CD-ROM data before writing it on the optical disc 3. SRAM1
A memory 8 stores program variables and the like and is also used as a work area when the CPU 11 performs various control processes. CD-ROM decoder (CD-ROM DEC
The ORDER) 19 is an LSI for demodulating the reproduced CD-ROM data. Audio controller (AUD
The IO CONTROLLER 20 is an LSI that controls music reproduction. System controller (S
YSTEM CONTROLLER) 21 is CPU1
1 is an LSI that controls recording / reproduction of information on / from the optical disc 3 based on the control of 1.

CD encoder (CD ENCODE
R) 22 is an LSI that modulates the user data and the sub-code so as to conform to the disc standard before recording the data on the optical disc 3. CD / DVD decoder (CD
/ DVD DECORDER) 23 is an LSI (CD) that separates and demodulates the data reproduced from the optical disc 3 into user data and subcode. Also, the optical disc 3
It is an LSI (DVD) that decodes the data reproduced from the user data as user data. Servo (SERVO) unit 24
Is a focus servo that controls the light spot of the light emitted from the pickup to the focus position on the disc surface during playback, and a tracking servo that controls the light spot to correctly follow the track formed on the disc surface. To do. Spindle controller (SPINDLE
The CONTROLLER 25 is an LSI that controls the rotation of the optical disc 3.

That is, the system controller 21 described above.
However, the control of rotating the stamp disc or the optical disc, which is the information recording medium on which information is recorded by the information recording device, at a plurality of types of rotation speeds based on the reproduction command from the host computer and reproducing the information on the optical disc is performed. Take charge. Further, when the playback command is executed from the host computer, the playback position is obtained from the playback command, the final position of the information that is played back from the optical disc and buffered, and the rotation time calculated from the playback position is predetermined. If it is within the time of, the function of the buffering means for causing the optical disk to wait for rotation without seeking and reproducing the information from the position on the optical disk based on the reproduction position to perform the buffering process is also fulfilled.

Further, there are control means for controlling the buffering processing so as to be performed only during reproduction from the optical disk, and means for setting the predetermined time so as to be different depending on the rotation speed of the optical disk. , If there is a packet or track joint between the last buffered position on the optical disc and the playback position, the rotation wait is prohibited and the seek is performed directly to the playback position of the optical disc to perform playback. It also functions as a means of doing.

Next, the CD-R / RW drive device 1
The buffering process in will be described. In this buffering process, while the data on the optical disk 3 is being reproduced and buffered, the host computer 2
When a reproduction command from the optical disc 3 is received, the optical disc 3 is directly read based on the rotation time obtained from the final address (final position) of the buffered data on the optical disc 3 and the reproduction address (reproduction position) in the reproduction command. Either the seek or the buffering is continued, whichever has the shorter processing time is adopted and executed. That is, when reproducing a sector that is not buffered, the reproduction is executed in the shorter time of either waiting for the address to be buffered as it is or directly seeking and reproducing.

Further, if there is no free space in the DRAM 15 at the time of the processing, buffering cannot be performed. Therefore, as the processing relating to claim 2 of the present invention, the DRAM 1 is used in the above processing.
A process for controlling so as to continue buffering only when there is a vacancy in 5 is also performed. Therefore, when the buffering is not possible, the reproduction is completed, so that a seek is inevitably entered at the next reproduction command from the host computer 2.

Further, if there is a packet or track joint between the final position of the currently buffered optical disk 3 and the reproduction position, the buffering ends with a reproduction error. After that, since it is necessary to seek and move to the target address, both the reproduction processing up to the error sector and the seek processing thereafter are executed, and the processing time is wasted.

Therefore, as a process relating to claim 4 of the present invention, the system controller 21 is used in the above process.
Checks in advance whether or not there is a sector that causes a reproduction error between the target reproduction position X and the final position Y, and if there is a sector that causes an error, seeks directly. At the time of reproducing data, since reproduction is performed based on a reproduction signal obtained from the optical disc 3, for example,
If there is an unrecorded sector that can exist on the CD-R / RW disc, a reproduction error occurs. There is a recording method such as track-at-once like a CD-R disc. When recording is performed by this method, there is a link portion which is a joint between tracks,
The link part is difficult to reproduce. If there is such a sector between the two, if the above process is performed as it is, an error will occur during buffering up to the target address and a seek will be involved again, so perform a seek from the beginning. If you do this, you can save extra time.

FIG. 2 is a flowchart showing the processing relating to claims 1, 2 and 4 of the present invention in the CD-R / RW drive device 1. System controller 21
Starts the buffering process of reproducing the data of the optical disc from the beginning and storing it in the DRAM in step (indicated by "S" in the figure) 1, and in the meantime, in step 2, whether the reproduction command from the host computer is received. Confirm whether or not. When a reproduction command is received from the host computer in the determination in step 2, the reproduction position (X) is acquired from the reproduction command in step 3.

At step 4, the final position (Y) of the data buffered in the DRAM is acquired, and at step 5, the track or packet joint (link part) is provided between the reproduction position (X) and the final position (Y). ) Is present, and if there is a joint, the process proceeds to step 8 to directly seek to the reproduction position (X) of the optical disk to start buffering. If there is no joint in the judgment in step 5, buffering is continued as it is. In this way, PMA, table of contents information (TOC), pre-gap (P
Since the track information can be known by reGAP, the track (Track) and the link (Link) position of the packet (Packet) can be known, and a playback error during buffering can be prevented in advance, and both buffering and seek operations can be performed. You don't have to do it (seek 1
Times), the playback performance is further improved.

In step 6, a threshold value (Z) corresponding to a predetermined time for determining whether to seek directly to the optical disk or continue buffering is loaded (for example, stored in the flash ROM 12 in advance), and the current value is stored. The address of the optical disc for which buffering has been completed, that is, the final position (Y) of the information that is reproduced from the optical disc and buffered is checked, and the final position (Y) is determined based on the current reproduction speed (rotation speed of the optical disk). The rotation time from Y) to the reproduction position (X) (time from Y to X) is calculated, and in step 7, it is determined whether the rotation time is within the threshold (Z).

If the rotation time is longer than the threshold value (Z) in the judgment in step 7 (the rotation time is longer than the threshold time), in step 8, a seek is directly made to the reproduction position (X) of the optical disk. Run and start buffering. Further, if there is no reproduction command in the determination in step 2 and if the rotation time is within the threshold value (Z) in the determination in step 7 (the rotation time is shorter than the threshold time), the prefetch processing is continued until the DRAM becomes full. The process of preliminarily reproducing and buffering the data on the optical disk is continued, and the process proceeds to step 9.

In step 9, it is judged whether or not there is a free space in the DRAM, and if there is no space, the buffering is stopped, and if there is, the process returns to step 1 to continue the buffering. In this way, the process proceeds, and when reproducing the unbuffered sector, it is decided whether to wait for the address to be buffered or to seek. This process improves playback performance.

Next, in the above process, for example, when rotating at 1 × speed, it takes 20 * 13.3 (ms) = 266 ms to buffer 20 sectors. In this case, since the value becomes larger than the seek time, the direct seek will speed up the data transfer to the host computer 2. Therefore, as the processing according to claim 3 of the present invention, the system controller 21 sets the threshold value (Z) to be different according to the rotational speed at the time of reproduction of the optical disk during the above processing.

That is, in the above processing, the threshold value (Z) corresponding to each reproduction speed is set in advance in a table (for example, stored in the flash ROM 12),
The system controller 21 loads and sets the threshold value (Z) corresponding to the reproduction speed (rotational speed) from the table at the time of reproduction in the processing of step 4 and sets the threshold value (Z).
The determination process of step 6 is performed based on

Table 1 is a list showing an example of data registered in the above table. In this table, the reproduction speed (rotational speed) and each threshold value (Z) are stored in association with each other. For example, at 40 times speed (40X), the rotation time per sector is 333 μs, and at 1 times speed (1X)
Since the rotation time per sector is 13.3 ms, the higher the reproduction speed, the shorter the rotation time. Therefore, at 40x speed, waiting for rotation is 2 compared to the seek time.
There is a margin of 0 sectors.

[0028]

[Table 1]

In this way, the CD-R / RW drive device 1 seeks between the position requested from the host computer 2 (target reproduction position (X)) and the current buffered final position (Y). If it is smaller than this, since the rotation waiting is performed and the buffering is performed, the reproduction data can be transferred to the host computer 2 earlier than when seeking. In other words, it is determined whether or not to seek in consideration of the rotation time to the target sector calculated from the current rotation speed. Since the buffered data is read, the playback performance can be improved.

Further, since the threshold value used for determining whether to seek or not is changed according to the rotation speed during reproduction, it is possible to appropriately determine whether to seek or buffer for each rotation speed. Further, when there is a joint between packets or tracks, useless buffering processing time can be avoided, so that the data transfer start time to the host computer can be shortened. The present invention can be implemented in the same manner as described above even for an information reproducing apparatus having only a reproducing function.

[0031]

As described above, according to the information reproducing apparatus of the present invention, the reproducing performance of the information recording medium can be improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a CD-R / RW drive device according to an embodiment of the present invention.

FIG. 2 is a flowchart showing a process relating to claims 1, 2 and 4 of the present invention in the CD-R / RW drive device 1 shown in FIG.

[Explanation of symbols]

1: CD-R / RW drive device 2: Host computer 3: Optical disc 11: CPU 12: Flash ROM (Flash ROM) 13: Host interface controller (HOST)
I / F CONTROLLER 14: Buffer Manager (BUFFER MANAG)
ER) 15: DRAM 16: Subcode operation controller (SUB)
CODE OPERATION CONTROL
R) 17: CD-ROM encoder (CD-ROM ENC
ORDER) 18: SRAM 19: CD-ROM decoder (CD-ROM DECO
RDER 20: Audio controller (AUDIO CONT)
ROLLER 21: System controller (SYSTEM CONT)
ROLLER 22: CD encoder (CD ENCODER) 23: CD / DVD decoder (CD / DVD DECO)
RDER 24: Servo (SERVO) unit 25: Spindle controller (SPINDLE CO)
NTROLLER 26: Interface (I / F)

Claims (4)

[Claims] 1. Information on the information recording medium is rotated by rotating an information recording medium such as a stamp disc or a disc on which information is recorded by an information recording device at a plurality of types of rotation speeds based on a reproduction command from a host computer. In the information reproducing apparatus for reproducing, the reproduction position is obtained from within the reproduction command when the reproduction command is executed from the host computer, and the final position of the buffered information is reproduced from the information recording medium. When the rotation time calculated from the reproduction position is within a predetermined time, the information recording medium is made to wait for rotation without seeking and information is reproduced from a position on the information recording medium based on the reproduction position. An information reproducing apparatus comprising a buffering means for performing a buffering process. 2. The information reproducing apparatus according to claim 1, wherein the buffering processing by the buffering means comprises:
An information reproducing apparatus provided with a control means for controlling so as to perform only during reproduction from the information recording medium. 3. The information reproducing apparatus according to claim 1 or 2, further comprising means for setting the predetermined time so as to be different depending on a rotation speed of the information recording medium. 4. The information reproducing apparatus according to claim 1, wherein when there is a joint of a packet or a track between the last buffered position on the information recording medium and the reproducing position, the rotation waiting is performed. The information reproducing apparatus is provided with a means for prohibiting the above and directly performing the reproduction by seeking directly to the reproduction position of the information recording medium.