WO2010073379A1 - Recording medium reproduction apparatus, recording medium reproduction method, recording medium reproduction program, and recording medium wherein recording medium reproduction program is stored - Google Patents

Abstract

Provide is a recording medium reproduction apparatus which can suppress deterioration in response by avoiding competition between prefetch access to alternation data and other access instructions as much as possible, a recording medium reproduction method, a recording medium reproduction program, and a recording medium wherein the recording medium reproduction program is stored. When an optical disc (12) is reproduced, a change in data inside a buffer (10) is simulated to estimate whether underflow will occur or not. When it is estimated that underflow will occur, simulation is performed again to calculate a prefetch position of the alternation data at which no underflow will occur, and the alternation data is prefetched at the position at which no underflow occurs.

Description

Recording medium reproducing apparatus, recording medium reproducing method, recording medium reproducing program, and recording medium storing recording medium reproducing program

The present invention stores a recording medium reproducing apparatus, a recording medium reproducing method, a recording medium reproducing program, and a recording medium reproducing program for reproducing a recording medium having a replacement area in which data is recorded instead of a defective area in the recording area The present invention relates to a recording medium.

For example, recording media capable of recording such as CD-R (Compact Disc-Recordable) and DVD-R (Digital Versatile Disc-Recordable) are known. For such a recording medium, data is recorded by irradiating the recording area with a laser beam. In the recording area, a defect in manufacturing the disc occurred after the manufacturing. Due to scratches or dirt, a defective area where data cannot be recorded / reproduced is generated. Therefore, in order to compensate for the loss of recording capacity due to the defective area, a replacement recording area (replacement area) is secured. Therefore, data that should originally be written in the defect area can be recorded in the replacement area, and all desired data is recorded on the disc.

However, when the recording medium is read, if a part of the data is recorded in the replacement area, the seek operation of the optical pickup is performed in order to access the recording area from the recording area and from the replacement area to the recording area. Will occur. Due to this seek operation, the data reading is temporarily interrupted, and the read data is not transferred during that time, resulting in a problem that the transfer rate of the reproduction data is lowered.

Further, in recent recording medium playback apparatuses, a buffer or the like for temporarily storing data read from the recording medium and played back is often provided in order to ensure a transfer rate of playback data. If the seek operation of the optical pickup frequently occurs to access the recording area, the data stored in the buffer disappears (or becomes very small) and the data transfer is interrupted due to an underflow state.

In response to the above-described problem, a disk drive device described in Patent Document 1 has been proposed. The disk drive device described in Patent Literature 1 determines whether or not the loaded disk is a disk that has undergone a replacement process, and if it is determined that the disk has been subjected to a replacement process, When it is determined whether or not an instruction from the computer is being executed and it is determined that the instruction is not being executed, the replacement data is reproduced by accessing the replacement sector and stored in the cache memory. In this way, the read rate of the reproduction data is not lowered by prefetching the replacement sector when the host computer is in the idle state (reading the replacement sector in advance before accessing the defective sector).
JP 2002-56619 A

However, the disk drive device described in Patent Document 1 has a problem that when an instruction is issued from the host computer during prefetch access to the replacement data, the time until execution of the instruction processing is delayed. That is, in the disk drive device described in Patent Document 1, since there is a defective sector and a read-ahead access to the replacement data always occurs unless an instruction from the host computer is executed, the pre-read access to the replacement data is performed. When an instruction from the host computer is issued, the time until execution of instruction processing is delayed. As a result, the response of the entire apparatus may be reduced, and smooth operation may not be possible.

Accordingly, the present invention provides a recording medium reproducing apparatus, a recording medium reproducing method, a recording medium reproducing program, and a recording medium capable of avoiding contention between prefetched access to alternate data and other access instructions as much as possible and suppressing a decrease in response. It is an object of the present invention to provide a recording medium storing a medium reproduction program.

In order to solve the above-mentioned problem, a recording medium reproducing apparatus according to claim 1 is configured to record data from a recording medium having a recording area, a replacement area, and a management area in which information on a defective area included in the recording area is recorded. In a recording medium reproducing apparatus, comprising: reproducing means for reading and reproducing; storage means for storing data reproduced by the reproducing means; and output means for outputting data stored in the storing means. An identification means for identifying whether or not replacement processing is being performed, and a predetermined predetermined value from the position where the reproduction means reads data when the identification means identifies that the recording medium is being replaced Predicting means for predicting whether or not the storage means will be in an underflow state within the section, and the reproducing means to access the defective area based on the prediction result by the predicting means. Is characterized with prefetch control means for prefetching the replacement data of the replacement area corresponding to prior to the scan, further comprising: a.

The recording medium reproduction method according to claim 7 reads and reproduces data from a recording medium having a recording area, a replacement area, and a management area in which information of a defective area included in the recording area is recorded, and the reproduction is performed. In a recording medium reproducing method for storing data in a storage means and outputting the data stored in the storage means, when it is identified that a replacement process is being performed on the recording medium, the data is read from the recording medium It is predicted whether or not the storage means will be in an underflow state within a predetermined interval determined from the position where it is, and the replacement data of the replacement area before accessing the defective area based on the predicted result Is prefetched.

The recording medium reproduction program according to claim 8, wherein the reproduction means reads and reproduces data from a recording medium having a recording area, a replacement area, and a management area in which information of a defective area included in the recording area is recorded, In a recording medium reproduction program for causing a computer to function as a storage means for storing data reproduced by the reproduction means and an output means for outputting data stored in the storage means, the recording medium is subjected to a replacement process. Identification means for identifying whether or not the recording medium has been replaced by the identification means, the storage means stores the data within a predetermined interval from a position where the reproduction means reads the data. Prediction means for predicting whether or not the means will be in an underflow state, and the defective area in the reproduction means based on the result predicted by the prediction means It is characterized with prefetch control means for prefetching the replacement data of the replacement area corresponding to the prior access, that causes the computer to function with.

1 is a block diagram of an optical disc playback apparatus according to an embodiment of the present invention. It is explanatory drawing which showed the structure of the data storage area of the optical disk reproduced | regenerated with the optical disk reproduction | regeneration apparatus shown by FIG. It is explanatory drawing of a change process. It is explanatory drawing which showed the change of the data amount in the buffer at the time of reproduction | regeneration operation | movement when a defective sector does not exist in an optical disk. It is explanatory drawing which showed the change of the data amount in the buffer at the time of reproduction | regeneration operation | movement when a defective sector exists in an optical disk. It is explanatory drawing which showed the change of the data amount in a buffer when the alternative area is prefetched and underflow does not generate | occur | produce. 3 is a flowchart of an alternate processing operation in the optical disc playback apparatus shown in FIG. 1.

Explanation of symbols

1 Optical disk playback device (recording medium playback device)
9 Audio / Video signal processing section (output means)
10 Buffer (storage means)
11 Microcomputer (identification means, prediction means, prefetch control means)
12 Optical disc (recording medium)
15 Reproduction unit (reproduction means)

Hereinafter, a recording medium playback apparatus according to an embodiment of the present invention will be described. According to an embodiment of the present invention, there is provided a recording medium reproducing apparatus that stores a storage unit within a predetermined interval at which the reproducing unit reads data when the identifying unit identifies that a replacement process is being performed on the recording medium. Is predicted by the prediction means, and based on the predicted result, the prefetch control means causes the reproduction means to prefetch the replacement data of the corresponding replacement area before accessing the defective area. Since it is possible to predict whether or not an underflow will occur in the storage means in advance and pre-read the replacement data based on the prediction, and the host computer only needs to pre-read the replacement data according to the prediction result. Even during idling, it is not always necessary to prefetch, and the possibility of contention between the prefetch access of the alternate data and other instructions can be reduced. Therefore, it is possible to suppress a decrease in response.

Further, the predicting means includes the number of defective areas in the predetermined section, the speed at which the reproducing means reads data from the recording medium, the speed at which the output means outputs data from the storage means, and a predetermined position in the recording area of the reproducing means. Seek time during which the reproducing means moves from the defective area to the replacement data of the corresponding replacement area, and seek time when the reproducing means moves from the replacement data to the data to be accessed next to the defective area Based on the above, it may be predicted whether or not the storage means enters an underflow state within the section. By doing so, it is possible to predict whether or not the storage means is in an underflow state by performing a simulation.

The prefetch control means may not perform prefetching of the replacement data when the prediction means predicts that the storage means will not be in an underflow state. By doing so, since prefetching is not performed when there is no problem in the reproduction operation, the prefetching operation can be minimized, and the frequency of seek to the replacement data can be reduced.

In addition, when the prefetch control unit predicts that the storage unit is in an underflow state in the prediction unit, the prefetch control unit prefetches corresponding replacement data in order from the defect region close to the current reading position among the defect regions in the predetermined section. Assuming that the prediction means may make a prediction again. By doing so, it is possible to confirm that underflow does not occur reliably by performing prefetching.

Further, the prediction means may calculate the timing for performing the prefetching at the time of prediction again. By doing so, it is possible to prefetch the replacement area at a timing at which underflow does not occur.

Further, the prefetch control means may prefetch the replacement data assumed to be prefetched when it is predicted that the underflow state will not occur as a result of the prediction by the prediction means again. By doing in this way, it is possible to prefetch only the replacement data required for preventing underflow from occurring.

The recording medium playback method according to an embodiment of the present invention stores data within a predetermined interval from a position where data is read from the recording medium when it is identified that the replacement process is performed on the recording medium. Since it is predicted whether the means will be in an underflow state and the replacement data of the corresponding replacement area is pre-read before accessing the defective area based on the predicted result, an underflow has occurred in the storage means in advance. Since it is possible to pre-read replacement data based on the prediction and to pre-read the replacement data according to the prediction result, the host computer always pre-reads even when the host computer is idle. There is no need, and the possibility of contention between the read-ahead access of the alternate data and other instructions can be reduced. Therefore, it is possible to suppress a decrease in response.

The recording medium playback program according to one embodiment of the present invention may cause the storage means to underflow within a predetermined interval from that time when the identification means identifies that the replacement process is being performed on the recording medium. Prediction means predicts whether or not a state is reached, and the prefetch control means causes the reproduction means to prefetch the replacement data of the corresponding replacement area before accessing the defective area based on the predicted result. It is possible to predict whether or not underflow will occur in the means and prefetch the replacement data based on the prediction, and it is sufficient to prefetch the replacement data according to the prediction result. Even if it exists, it is not always necessary to prefetch, and the possibility of contention between the prefetch access of the alternate data and another instruction can be reduced. Therefore, it is possible to suppress a decrease in response.

Further, the above-described recording medium reproduction program may be stored in a computer-readable recording medium. In this way, the recording medium playback program can be distributed alone, in addition to being incorporated into the device, and version upgrades can be easily performed.

An optical disk reproducing apparatus 1 as a recording medium reproducing apparatus according to an embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 1, the optical disk reproducing apparatus 1 includes a disk motor 2, an optical pickup 3, a carriage motor 4, a lead screw 5, an RF amplifier 6, a servo signal processing unit 7, a driver 8, a sound / A video signal processing unit 9, a buffer 10, and a microcomputer 11 are provided.

The disc motor 2 is a motor for rotating the optical disc 12 as a recording medium set in the optical disc reproducing apparatus 1, and is composed of a spindle motor or the like.

The optical pickup 3 includes a laser diode that generates laser light to be applied to the optical disk 12, an objective lens for condensing the laser light from the laser diode on the optical disk 12, and a focus direction and a signal from the servo signal processing unit 7. Photodiode comprising an actuator for driving the objective lens in the tracking direction and a photodiode for receiving the reflected light reflected from the optical disk 12, an optical system for guiding the laser light to the objective lens, and guiding the reflected light to the light receiver, etc. From the output, an RF signal including a track data such as video and music recorded on the optical disk 12, a focus error signal, a tracking error signal, and the like are generated and output to the RF amplifier 6.

The carriage motor 4 is a motor for moving the optical pickup 3 in the radial direction of the optical disk 12 through a lead screw 5 to be described later, and includes a stepping motor or the like.

The lead screw 5 is formed in a columnar shape, and a thread groove and a thread are formed on the outer peripheral surface thereof, and is installed in parallel with the radial direction of the optical disk 12. The lead screw 5 is mechanically connected to the rotation shaft of the carriage motor 4 and rotates in accordance with the rotation of the carriage motor 4. The screw grooves and screw threads of the lead screw 5 are engaged with screw threads and screw grooves (not shown) formed in the optical pickup 3, and the optical pickup 3 moves along the radial direction of the optical disk 17 by the rotation of the lead screw 5. To do.

The RF amplifier 6 amplifies the signal input from the optical pickup 3 to a predetermined value and outputs it to the servo signal processing unit 7.

The servo signal processing unit 7 controls the focus and tracking by driving the actuator of the optical pickup 3 based on the control signal such as the focus error signal and the tracking error signal inputted from the RF amplifier 6 and is recorded on the optical disk 12. To read the information correctly. Further, the level of the input focus error signal is output to the microcomputer 13. Further, the RF signal including video and music recorded on the optical disk 12 is analog / digital converted and output to the audio / video signal processing unit 9.

The driver 8 generates and outputs a drive signal to the actuator of the disk motor 2 and the optical pickup 3 and the carriage motor 4 from the signal input from the servo signal processing unit 7.

The audio / video signal processing unit 9 performs error correction and the like on the signal input from the servo signal processing unit 7, performs demodulation and decoding, and outputs the result to the buffer 10. Then, it is read from the buffer 10 according to a request from the microcomputer 11 and output to the host computer 20.

Here, the disk motor 2, the optical pickup 3, the carriage motor 4, the lead screw 5, the RF amplifier 6, the servo signal processing unit 7, the driver 8, and the audio / video signal processing unit 9 read data from the optical disk 12 and reproduce it. A reproducing unit 15 as means is configured.

The buffer 10 serving as a storage means is a memory for storing data such as video and audio reproduced by the audio / video signal processing unit 9 temporarily by a predetermined amount so that reproduction is not interrupted by vibration or the like. Consists of. The buffer 10 stores data read from the optical disk 12 at a normal playback speed of several times normal speed and outputs it at a normal playback speed.

The microcomputer 11 as an identification unit, a prediction unit, and a prefetch control unit includes a CPU (Central Processing Unit), a RAM (Random Access Memory), and a ROM (Read Only Memory). Based on this, the entire optical disc playback apparatus 1 is controlled in each operation such as insertion, ejection, playback, stop and track search of the optical disc 12. Further, the microcomputer 11 infers whether or not to pre-read data stored in the alternate area during the reproducing operation of the optical disk 12, and causes the reading / reproducing unit 15 to pre-read if necessary. Note that prefetching refers to reading replacement data in advance before accessing a defective sector as described in the prior art, that is, reading replacement data in a corresponding replacement area before accessing the defective area. It is.

As shown in FIG. 2, the optical disk 12 has a lead-in area, a data area, and a lead-out area. In the lead-in area as the management area, an address of a defective sector as a defective area in a user data area to be described later, an address of a replacement sector (alternative data) in a replacement area corresponding to the defective sector, and the like are recorded. Information indicating the end of the data area is recorded in the lead-out area.

The data area has a user data area and a replacement area. Data to be reproduced by the optical disc playback apparatus 1 is recorded in the user data area as a recording area, and a defective sector in the user data area is recorded in the replacement area. The data that should be recorded is recorded in the. In FIG. 2, a plurality of replacement areas are provided, but one replacement area may be provided. One replacement area may be composed of a plurality of sectors. That is, data corresponding to a plurality of defective sectors may be recorded in one replacement area.

The replacement process has been described in the prior art, but will be described in detail with reference to FIG. If there is a defective sector in the user data area, data that was originally scheduled to be recorded in that sector is recorded in the replacement area, and replacement information such as the address of the defective sector and the address of the replacement area is recorded in the lead-in area. When data is read, when a defective sector is accessed, data is read from the replacement area with reference to replacement information. In the case of FIG. 3, if the defective sectors are sector 3 and sector 7 among sectors 1 to 9 in the user data area, and the corresponding replacement sectors are sector C and sector F in the replacement area, When accessing sequentially from 1, the sectors are accessed in the order of sectors 1, 2, C, 4, 5, 6, F, 8, and 9.

Next, a change in the amount of data in the buffer 10 during the reproducing operation in the optical disc reproducing apparatus 1 configured as described above will be described with reference to FIGS. 4 and 5. FIG.

FIG. 4 is a diagram showing a change in the amount of data in the buffer 10 during the reproduction operation when there is no defective sector on the optical disc 12. In FIG. 4, reproduction of the optical disk 12 is started and data is accumulated in the buffer 10 (period A). When data is fully accumulated in the buffer 10, reading of data from the optical disk 12 is stopped and data is output to the host computer 20, thereby reducing the data amount (period B). At this time, the optical pickup 3 continues to follow the track of the optical disk 12. That is, the optical pickup 3 moves in the same manner as when reading data. If the re-seek start capacity is less than the preset re-seek start capacity, the time (period B1) required for seeking from the position of the optical pickup 3 at that time to the restart position (the position of the data next to the data whose reading has been stopped) Thereafter, reading of data from the optical disk 12 is resumed, and data starts to be accumulated again. Thereafter, these periods are repeated.

FIG. 5 is a diagram showing a change in the amount of data in the buffer 10 during the reproducing operation when a defective sector is present on the optical disk 12. In FIG. 5, similarly to FIG. 4, the period A and the period B have elapsed, and when the position of the defective sector is reached during the next period A, seek is performed from the position of the defective sector to the replacement data of the replacement area of the optical disk 12. During this period, only data output is performed and the amount of data decreases (period C). When seeking to the replacement data, the amount of data increases because the replacement data is read from the replacement area (period D). After the replacement data in the replacement area is read, the amount of data decreases because of seeking to the sector next to the defective sector in the user data area (period E). Then, reading is started from the data of the sector next to the defective sector in the user data area.

In the example of FIG. 5, the defective sector is detected twice thereafter, and the buffer 10 falls into an underflow state by repeating the period C to E each time.

Therefore, in this embodiment, when the replacement information is recorded by reading the lead-in area, it is identified that the replacement process is being performed, and the optical pickup 3 is read in advance from the reading position at a predetermined time point during reproduction. An increase / decrease in the amount of data as shown in FIG. 5 (that is, a waveform as shown in FIGS. 4 and 5) within a predetermined interval is simulated to predict whether an underflow will occur within the predetermined interval.

Information necessary at the time of simulation includes the number of defective sectors in a predetermined section from the data reading position at that time, the data increase rate in the period A (straight line), the data decrease rate in the period B (straight line), Re-seek time to the restart position when the re-seek start capacity falls below, seek time from the defective sector in the user data area to the replacement data in the replacement area, the data increase rate (straight line) in the replacement area, and replacement The seek time from the replacement data of the area to the next sector of the defective sector in the user data area is required.

The number of defective sectors in a predetermined section can be obtained by reading replacement information from the lead-in area of the optical disc 12. The data increase rate (straight line) in the period A and the data increase rate (straight line) in the replacement area can be calculated based on the data reading speed from the optical disc 12 and the data transfer speed from the buffer 10 to the host computer 20. . The data reduction rate (straight line) in the period B can be calculated by the data transfer rate from the buffer 10 to the host computer 20. The re-seek time to the restart position when the re-seek start capacity falls below can be calculated from the average of seek times in the user data area. The seek time from the defective sector in the user data area to the replacement data in the replacement area can be calculated from the distance from the defective sector to the replacement data. The seek time from the replacement data to the next sector of the defective sector can be calculated from the distance from the replacement data to the next sector of the defective sector. As described above, the information necessary for the simulation can be calculated from information acquired or found in advance. Therefore, it is possible to predict whether or not underflow occurs by performing a simulation that reproduces the waveform of FIG.

If it is predicted whether or not underflow will occur in the buffer 10, and if it is predicted that underflow will occur, the defective sector is pre-read while the data amount in the buffer 10 has a margin as shown in FIG. Re-simulation is performed assuming that At this time, the prefetch timing at which underflow does not occur is also calculated. In the case of FIG. 6, re-simulation is performed on the assumption that the defective sector 1 of FIG. If it can be confirmed by the re-simulation that no underflow occurs, the replacement data is pre-read at the same time.

FIG. 7 shows a flowchart of the detailed operation of the operation described above. The flowchart shown in FIG. 7 is executed by the microcomputer 11.

First, in step S1, data reading from the optical disk 12 is started, and the process proceeds to step S2. That is, the signal taken from the optical pickup 3 is reproduced as data via the RF amplifier 6, the servo signal processing unit 7, and the audio / video signal processing unit 9 and stored in the buffer 10. The data stored in the buffer 10 is read by the microcomputer 11 in accordance with an instruction from the host computer 20 and output to the host computer 20.

Next, in step S2, the buffer capacity is simulated up to 0x2000 sectors ahead as a predetermined section. Since 0x2000 indicates 2000 in hexadecimal display, it is 8192 in decimal display. Of course, the 0x2000 sector is an example, and any number of sectors may be used. That is, the number of defective sectors in a predetermined section, the data increase rate in the period A (straight line), the data decrease rate in the period B (straight line slope), and the restart position when it falls below the re-seek start capacity. Re-seek time, seek time from defective sector in user data area to replacement data in replacement area, data increase rate (straight line) in replacement area, replacement data in replacement area next to defective sector in user data area The waveform shown in FIG. 4 or FIG. 5 is simulated from the seek time to the sector.

Next, in step S3, it is determined whether or not an underflow occurs in the buffer 10 as a result of the simulation in step S2. If it occurs (if Y), the process proceeds to step S4, and if not (if N). Advances to step S7.

Next, in step S4, a seek start point is calculated in which the buffer does not underflow even if prefetch access is performed in the simulation. That is, a condition that does not cause underflow is calculated. This corresponds to the re-simulation described above. That is, in addition to predicting whether or not underflow will occur after reading the replacement data, a prefetch seek start point that does not underflow is also calculated. In short, the time margin for prefetching is also calculated. That is, assuming that the replacement data corresponding to the defective sector nearest to the current reading position has been pre-read, the prediction is performed again and the pre-read timing is calculated.

Next, in step S5, it is determined whether or not the seek start point has been read. If it is the seek start point (in the case of Y), the process proceeds to step S6, and if not (in the case of N), the process proceeds to step S9. .

Next, in step S6, prefetch access to the replacement data is performed, and the process returns to step S2. In this step, the replacement data corresponding to the defective sector to be prefetched is sought and read. That is, since it is predicted that the underflow state will not occur as a result of re-prediction, replacement data assumed to be pre-read is read.

On the other hand, in step S7, it is determined whether or not data of 0x1000 sectors (decimal number of 4096 sectors) has been read from the optical disk 12. If read (if Y), the process returns to step S2, and if not read (N In the case of (), the process proceeds to step S8. In this step, it is determined whether or not 0x1000 sectors have been read from the simulation in step S2, and if read, the process returns to step S2 to perform another simulation. That is, in this flowchart, the simulation of step S2 is performed every 0x1000 sectors.

Next, in step S8, it is determined whether or not a buffer clear has occurred. If it has occurred (in the case of Y), the process returns to step S2, and if it has not occurred (in the case of N), the process returns to step S7. The buffer clear indicates a state in which the data in the buffer 10 is cleared by changing the access position in the optical disk 12 by an instruction from the host computer 20 such as a track jump. In this state, the buffer is cleared again. It is necessary to perform a simulation based on data stored later. In other words, when passing through the path for executing steps S7 and S8, it is predicted that the underflow state will not occur, and the prefetching of the replacement data is not performed.

In step S9, it is determined whether or not a buffer clear has occurred. If it has occurred (in the case of Y), the process returns to step S2, and if it has not occurred (in the case of N), the process returns to step S5. Similarly to step S8, in this step, when the buffer is cleared, the simulation is performed again based on the data stored after the clearing.

According to the present embodiment, when the optical disk 12 is reproduced, the number of defective sectors in the section 0x2000 sectors ahead, the data increase rate when reading data from the optical disk 12, and the data decrease rate when stopping reading data from the optical disk 12, From the re-seek time to the restart position when the re-seek start capacity is exceeded, the seek time from the defective sector in the user data area to the replacement data in the replacement area, the data increase rate in the replacement area, and the replacement data in the replacement area It is predicted whether or not underflow will occur by simulating the change in data in the buffer 10 from the seek time to the next sector of the defective sector in the user data area. A simulation is performed again to calculate the prefetch position of the alternate data that does not occur. Since There has performed preread replacement data in a position that does not occur, in terms of reliably underflow was confirmed that does not occur, it is possible to perform prefetching minimal replacement data. Therefore, it is not always necessary to prefetch even when the host computer is in an idle state, and the possibility that the prefetch of the alternate data and other instructions will compete can be reduced.

Also, if underflow does not occur as a result of the simulation, the replacement data is not prefetched, so the frequency of seek to the replacement area can be reduced.

In the above-described embodiment, when underflow occurs even when immediately prefetching when calculating the prefetch timing by re-simulation, the simulation may be performed assuming that the next defective sector is also read. .

In the above-described embodiments, the optical disk such as CD-R or DVD-R has been described as the recording medium. However, the recording medium is not limited to this and is a recording medium such as a magneto-optical disk or magnetic disk such as MD (Mini-Disc). Applicable if available.

According to the above-described embodiment, the following optical disc playback apparatus 1, recording medium playback method, and recording medium playback program can be obtained.

(Additional remark 1) The reproducing part 15 which reads and reproduces | regenerates the data from the optical disk 12 which has the lead-in area | region where the information of the defective sector contained in a user data area | region and replacement area | region, and a user data area | region was reproduced | regenerated In an optical disc playback apparatus 1 including a buffer 10 for storing data and an audio / video signal processing unit 9 for outputting the data stored in the buffer 10,
A microcomputer 11 for identifying whether the optical disk 12 is undergoing a replacement process;
When the microcomputer 11 identifies that the replacement process is being performed on the optical disc 12, it is predicted whether or not the buffer 10 will be in an underflow state within a predetermined interval from the position where the reproducing unit 15 reads data. A microcomputer 11 that
A microcomputer 11 that prefetches replacement data of a corresponding replacement area before accessing the defective sector based on a result predicted by the microcomputer 11;
An optical disc reproducing apparatus 1 comprising:

According to this optical disk reproducing apparatus 1, it is possible to predict whether or not an underflow will occur in the storage means in advance and pre-read the replacement data based on the prediction, and the replacement data can be pre-read according to the prediction result. Therefore, it is not always necessary to prefetch even when the host computer 20 is idle, and the possibility of contention between the prefetch access of the alternate data and other instructions can be reduced. Therefore, it is possible to suppress a decrease in response.

(Supplementary Note 2) Data is read from and reproduced from the optical disk 12 having a lead-in area in which information on defective sectors included in the user data area, the replacement area, and the user data area is recorded, and the reproduced data is stored in the buffer 10 Then, in the recording medium reproduction method for outputting the data stored in the buffer 10 according to the instruction,
When it is identified that the replacement process has been performed on the optical disc 12, it is predicted whether or not the buffer 10 will be in an underflow state within a predetermined interval from the position where data is read from the optical disc 12, and the prediction A recording medium reproducing method comprising: prefetching replacement data of a replacement area before accessing a defective sector based on a result.

According to this recording medium playback method, it is possible to predict in advance whether or not an underflow will occur in the storage means and to prefetch the replacement data based on the prediction, and to read the replacement data in advance according to the prediction result. Therefore, it is not always necessary to prefetch even when the host computer 20 is idle, and the possibility of contention between the prefetch access of the alternate data and other instructions can be reduced. Therefore, it is possible to suppress a decrease in response.

(Additional remark 3) The reproducing part 15 which reads and reproduces | regenerates the data from the optical disk 12 which has the lead-in area | region where the information of the defective sector contained in a user data area | region and replacement area | region, and a user data area | region was reproduced | regenerated In a recording medium reproduction program for causing a computer to function as a buffer 10 for storing data and an audio / video signal processing unit 9 for outputting the data stored in the buffer 10 according to a command,
A microcomputer 11 for identifying whether the optical disk 12 is undergoing a replacement process;
When the microcomputer 11 identifies that the replacement process is being performed on the optical disc 12, it is predicted whether or not the buffer 10 will be in an underflow state within a predetermined interval from the position where the reproducing unit 15 reads data. A microcomputer 11 that
A microcomputer 11 that prefetches replacement data of a corresponding replacement area before accessing the defective sector based on a result predicted by the microcomputer 11;
And a recording medium reproduction program for causing the computer to function.

According to this recording medium playback program, it is possible to predict whether or not an underflow will occur in the storage means in advance, and to prefetch the replacement data based on the prediction, and to read the replacement data in advance according to the prediction result. Therefore, it is not always necessary to prefetch even when the host computer 20 is idle, and the possibility of contention between the prefetch access of the alternate data and other instructions can be reduced. Therefore, it is possible to suppress a decrease in response.

It should be noted that the above-described embodiments are merely representative forms of the present invention, and the present invention is not limited to the embodiments. That is, various modifications can be made without departing from the scope of the present invention.

Claims (9)

Reproducing means for reading and reproducing data from a recording medium having a recording area and replacement area, and a management area in which information of a defective area included in the recording area is recorded, and storage means for storing data reproduced by the reproducing means; An output means for outputting the data stored in the storage means,
Identifying means for identifying whether the recording medium is undergoing a replacement process;
Whether or not the storage means is in an underflow state within a predetermined interval from the position where the reproduction means reads data when the identification means identifies that the replacement process is being performed on the recording medium. A prediction means to predict;
Prefetch control means for prefetching the replacement data of the corresponding replacement area before accessing the defective area based on the result predicted by the prediction means;
A recording medium reproducing apparatus comprising: The predicting means includes the number of defective areas in the predetermined section, the speed at which the reproducing means reads data from the recording medium, the speed at which the output means outputs data from the storage means, and the reproduction means A seek time between predetermined positions in the recording area, a seek time when the reproducing means moves from the defective area to the replacement data of the corresponding replacement area, and a reproducing means from the replacement data to the defective area. 2. The recording medium according to claim 1, wherein the storage unit predicts whether or not the storage unit enters an underflow state in the section based on a seek time when moving to data to be accessed next. Playback device. 3. The recording medium reproduction according to claim 1, wherein the prefetch control unit does not prefetch the replacement data when the prediction unit predicts that the storage unit is not in an underflow state. apparatus. The prefetch control means, when the predicting means predicts that the storage means is in an underflow state, the replacement corresponding in order from the defect area closest to the current reading position among the defect areas in the predetermined section. The recording medium reproducing apparatus according to any one of claims 1 to 3, wherein the prediction unit is made to predict again on the assumption that data has been pre-read. 5. The recording medium reproducing apparatus according to claim 4, wherein the predicting unit calculates a pre-reading timing at the time of the prediction again. The said prefetch control means prefetches the said replacement data assumed to prefetch, when it predicts that it will not become an underflow state as a result of the prediction of the said prediction means again, The pre-reading control means of Claim 4 or 5 characterized by the above-mentioned. Recording medium playback device. Reading and reproducing data from a recording medium having a recording area, a replacement area, and a management area in which information of a defective area included in the recording area is recorded, storing the reproduced data in a storage means, and the storage means In a recording medium reproduction method for outputting data stored in
When it is identified that a replacement process is being performed on the recording medium, it is predicted whether or not the storage means is in an underflow state within a predetermined interval from a position where data is read from the recording medium. A method of reproducing a recording medium, comprising: prefetching replacement data of the replacement area before accessing the defective area based on the predicted result. Reproducing means for reading and reproducing data from a recording medium having a recording area and replacement area, and a management area in which information of a defective area included in the recording area is recorded, and storage means for storing data reproduced by the reproducing means; In the recording medium reproduction program for causing the computer to function as output means for outputting the data stored in the storage means,
Identifying means for identifying whether the recording medium is undergoing a replacement process;
Predicting whether or not the storage means is in an underflow state within a predetermined interval where the reproduction means reads data when the identification means identifies that the replacement process is being performed on the recording medium Prediction means to
Prefetch control means for prefetching the replacement data of the corresponding replacement area before accessing the defective area based on the result predicted by the prediction means;
And a recording medium reproduction program for causing the computer to function. A computer-readable recording medium, wherein the recording medium reproduction program according to claim 8 is stored.

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