JP3941283B2 - Optical disc invalid session determination method, optical disc track information acquisition method, and optical disc apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method of determining an invalid session of a rewritable optical disc, a method of acquiring track information by TOC (Table of Contents), and an optical disc apparatus for carrying out these methods, and relates to a CD-RW (multi-session recorded CD-RW). This prevents accidental acquisition of old session data that should have been erased from a rewritable optical disc such as a compact disc (rewritable).
[0002]
[Prior art]
Multi-session recording is standardized as one of recording methods for CD-RW discs. In this case, a combination of a lead-in area, a program area, and a lead-out area is set as one session, and a plurality of sessions are recorded on one disc. In each session, the lead-in area stores TOC information that is information on tracks in each session. Although user data is stored in the program area, the path table in the previous session is often taken over here. In addition, recording is determined to record sessions in order from the inner periphery to the outer periphery of the disc.
[0003]
Therefore, in a multi-session compatible optical disc apparatus (CD-ROM drive, CD-R drive, CD-RW drive, etc.), all track information and the latest user data information (path table recorded in the last session) are acquired. Therefore, after the disc is loaded, the Q subcode information in the innermost lead-in area is read to determine that the disc is a multi-session recorded disc. After that, the path table of the final session is searched by exchanging with the host computer.
[0004]
As a method of searching for all track information up to the last session, there is a method of sequentially reading the lead-in area of each session. That is, first, the TOC information in the lead-in area of the first session is read, and the program start time information of the second session obtained at this time is used as a clue, and then the lead-in area of the second session is accessed. TOC information is read, and the program start time information of the third session obtained at this time is used as a clue, and then the lead-in area of the third session is accessed to read the TOC information of the third session. In this way, the lead-in area of each session is sequentially accessed. If there is no data in the lead-in area at the access destination, it is determined as an unrecorded part, and the immediately preceding session is determined as the last session. When all track information up to the final session is obtained, the host computer continues to search the path table of the final session by exchanging with the drive.
[0005]
By the way, conventional erase methods for erasing the entire surface of the CD-RW disc include full erase and quick erase. Full erase is a process in which logic “0” is written over the entire surface, and has the merit of completely erasing the recorded content, but has the disadvantage that it takes a long erasing time. For example, it takes 74 minutes or more to erase a 74 minute disc at 1 × speed. On the other hand, in the quick erase, the PMA area (Program Memory Area) located on the inner circumference side of the lead-in area of the first session: after the recording of the track of one session is completed, the TOC information of the session is generated to read the session. An area in which information on the start time and end time of each track in the session necessary for recording in the in area is written in. Note that the PMA area has track start times of all currently valid sessions already completed, The information on the end time is also left as it is.) And the first session lead-in area to the pre-gap are deleted (the information on the outer periphery side is left as it is). When the PMA area and the lead-in area of the first session are erased, the multi-session compatible optical disc apparatus loaded with the CD-RW disc has no information about the track from the PMA area or the lead-in area to be accessed first. Since it cannot be obtained, it is determined that the disk has all tracks erased. Therefore, the quick erase can achieve the same effect as the full erase with a short erase operation.
[0006]
[Problems to be solved by the invention]
Since the data after the first track of the first session still remains in the quick erased CD-RW disc, a problem may occur when a new multi-session recording is performed. That is, when a CD-RW disc that has been quick erased and is newly recorded up to the first session is loaded into the multi-session compatible optical disc apparatus, the optical disc apparatus starts from the lead-in area of the new first session to the start time of the program area of the second session. Information is acquired, and an address where the lead-in area of the second session should exist is accessed based on this information. At this time, if the data of the old session before the quick erase remains at the accessed position, it may be erroneously acquired. In particular, when it is data in the lead-in area of the old session, the optical disc apparatus erroneously determines it as data in the lead-in area of the second session, and based on the data, the lead-in area of the old session Are sequentially read, and all the remaining TOC information of the old session is acquired, and the path table of the old final session is acquired based on the TOC information of the old final session. As a result, even though the new first session is recorded on the optical disc, there is no information corresponding to the new first session in the acquired path table. Inaccessible. Further, even if an attempt is made to record the new second session, it cannot be recorded immediately after the new first session.
[0007]
The present invention solves the problems in the prior art and prevents invalid session determination method and track information from preventing erroneous acquisition of old session data that should have been deleted from a multi-session recorded rewritable optical disk. An acquisition method and an optical disc apparatus are to be provided.
[0009]
[Means for Solving the Problems]
  This inventionNoThe effective session determination method reads the start time information of the program area of the next session from the lead-in area of the session on the inner circumference side of the disc, and a position corresponding to the program area start time or a position before the program area start time Access to the position corresponding to the start time of the lead-in area of the next session defined as follows or an appropriately determined position between these two positions, and information read from the accessed position is configured in a logical erase format. If it is configured in the logical erasure format, the disk outer periphery side is determined as an invalid session after the next session.
[0014]
  This inventionNoThe rack information acquisition method reads the recorded information from the innermost lead-in area of the disc, and if the information includes the start time information of the program area of the next session, a predetermined time before the program area start time. The start time of the lead-in area of the next session defined as the position of the next session is obtained, and the position corresponding to the start time of the lead-in area or after that position is appropriately determined before the start position of the program area. This is a method of accessing the position, reading the recorded information of the lead-in area of the next session from the accessed position, and repeating this operation to read the lead-in area of each session and sequentially obtain the table of contents information of the disc.The
[0015]
  This inventionNoThe rack information acquisition method determines whether or not the information read from the accessed position is configured in the logical erasure format. If the information is configured in the logical erasure format, the reading is terminated and the previous session is terminated. The table of contents information is acquired as effective information.
[0017]
In additionTheIn the rack information acquisition method, after acquiring the table of contents information, the path table is acquired by accessing the position where the path table of the last session in which the table of contents information is valid is recorded by exchanging with the host computer. You can also.
[0019]
  This inventionLight ofThe disc device accesses the lead-in area on the innermost circumference of the disc and reads the recorded information at an appropriate time after the disc is loaded, and the information includes the start time information of the program area of the next session. If it is included, the start time of the lead-in area of the next session defined as a position a predetermined time before the start time of the program area is obtained and corresponds to the start time of the lead-in area Access a position that is appropriately determined before or after the start position of the program area at the position or after that position, read the recorded information in the lead-in area of the next session from the accessed position, and repeat this operation to While reading the session lead-in area, the table of contents information of the disc is acquired sequentially, and the next session read The information read from the accessed position is configured in a logical erasure format when accessing a position corresponding to the start time of the program area or a position determined after this position and before the start position of the program area. If it is configured in the logical erasure format, it is equipped with a control unit that performs control to end the reading and acquire the table of contents information up to the previous session as valid information It is.
[0024]
  In addition,lightIn the disk device, after acquiring the table of contents information, the path table can be acquired by accessing the position where the path table of the last session in which the table of contents information is valid is recorded by exchanging with the host computer. it can. In the present invention, a session refers to a block composed of a lead-in area, a program area, and a lead-out area.
[0025]
In the case of a CD-RW disc, currently valid track information is recorded in the PMA area. Therefore, in the case of a recordable drive such as a CD-R / RW drive that reads the PMA area, it is considered that the track information read from the PMA area can be effectively used for determining whether the session is valid or invalid. On the other hand, in the case of a read-only drive such as a CD-ROM drive or a DVD-ROM drive, generally, information in the PMA area cannot be used to determine whether a session is valid or invalid. In consideration of this point, the present invention can determine whether the session is valid or invalid without being based on the information of the PMA area, and thus is highly applicable to a read-only drive that does not have a function of reproducing the PMA area. However, even in a recordable drive such as a CD-R / RW drive (and in a read-only drive having a function of reproducing the PMA area), the determination method of the present invention is used alone, or the PMA area In combination with the determination based on the information read from the session, it is possible to determine whether the session is valid or invalid.
[0026]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below. Here, when the present invention is applied to an optical disc apparatus having a read-only drive that can reproduce a CD-RW disc such as a multi-session compatible CD-ROM drive, DVD-ROM drive, etc., and does not read the PMA area. Will be described. A multi-session compatible CD-ROM drive can reproduce CD-DA, CD-R, CD-RW, and CD-ROM discs. In addition to this, the DVD-ROM drive can further reproduce a DVD-ROM disc.
[0027]
First, the CD-RW multi-session format will be briefly described. As shown in FIG. 2, the recording area of the optical disc on which multi-session recording has been configured from the inner periphery side as a PMA area, a first session, a second session, a third session, and so on. Each session includes a lead-in area (LI), a program area (PGM), and a lead-out area (LO) from the inner periphery side. The TOC information of the session is recorded in the lead-in area. A path table is recorded in each session. In the path table of each session, directory information relating to the track of the own session and all sessions on the inner circumference side is recorded. Therefore, if the path table of the last session is acquired, it is possible to access any track of all sessions.
[0028]
The lead-in area of the first session is set at a position of 23 to 25 mm from the center of the disk. In addition, the length of the lead-out area of the first session is defined as 01 minutes 30 seconds 00 frames (hereinafter referred to as 01:30:30). Further, after the second session, the length of the lead-in area is set to 01: 00: 00: 00 and the length of the lead-out area is set to 00:30:30.
[0029]
The Q subcode format of each lead-in area is shown in FIG. A lead-in area can be seen by TNO = 0. The multi-session recording can be understood from the fact that in the case of a CD-R disc and a CD-ROM disc, a POINT = B0 state exists when ADR = 5 (mode 5). In the case of a CD-RW disc, the TIME when ADR = 5 (mode 5) and POINT = B0 is a value other than FF: FF: FF. TIME (A value other than FF: FF: FF) when ADR = 5 and POINT = B0 represents the start time of the program area of the next session. Also, PTIME when POINT = 1 to 99 represents the start time of the track number represented by the POINT value. PMIN when POINT = A0 represents the first track number of the session. PMIN when POINT = A1 represents the last track number of the session. PTIME when POINT = A2 represents the start time of the lead-out area of the session.
[0030]
FIG. 4 shows the Q subcode format of the program area and lead-out area of each session. A program area or a lead-out area can be recognized by TNO ≠ 0. TNO in the program area represents the track number at that position. In the lead-out area, TNO = AA (h). A section of INDEX = 0 is provided as a pre-gap between 00:02:00 from the start position of the program area. Therefore, the first track of the session is recorded after 00:02:00 from the start position of the program area. TIME represents the relative time in the track, and TIME represents the absolute time from the start position of the program area of the first session, and a value corresponding to the time information recorded as ATIP in the pregroove is recorded.
[0031]
Recording on the CD-RW disc is performed by sequentially writing tracks in the program area from the inner circumference side to the outer circumference side. Until the recording of one session is completed, every time recording is interrupted, the track information up to that point (information on the start time and end time of each track necessary for generating TOC information) is temporarily recorded in the PMA area. It accumulates sequentially. When the recording of one session is completed, the lead-in area is recorded based on the accumulated information, and the path table and the lead-out area are further recorded to complete the recording of the session.
[0032]
The quick erase of the CD-RW disc is performed by recording erase data in the respective erase formats in the normal PMA area, the lead-in area of the first session, and the pre-gap of the first session. Data on the outer peripheral side (that is, on the outer peripheral side from the first track) from the pre-gap of the first session is left as it is.
[0033]
An example of the system configuration of an optical disc apparatus to which the present invention is applied is shown in FIG. This is composed of a combination of a read-only optical disc drive 10 capable of reproducing a CD-RW disc, such as a multi-session compatible CD-ROM drive and DVD-ROM drive, and a host computer 12 such as a personal computer. An optical disk (CD-DA, CD-R, CD-RW, CD-ROM, DVD-ROM, etc.) 14 is driven by a spindle motor 16 and information is reproduced by an optical pickup 18. The optical pickup 18 is transported in the radial direction of the optical disk 14 by a feed motor 20. Data of the optical disk 14 read by the optical pickup 18 is subjected to EFM demodulation and error correction processing by the EFM / CIRC decoder 24 via the RF amplifier 22. The demodulated data is temporarily stored in the buffer memory 28 via the memory control unit 26, read out according to the internal reference clock and the jitter is absorbed, and then sent to the host computer 12 via the interface unit 30. It is done.
[0034]
The servo control unit 32 performs constant linear velocity control of the spindle motor 16, focus control of the optical pickup 18, tracking control, feed control of the feed motor 20, and the like based on the output signal of the RF amplifier 22. The system control unit 34 controls each unit in the optical disc drive 10 for executing the command and the like based on the command and the like from the host computer 12. The control unit of the optical disk apparatus according to the present invention is configured by a combination of the host computer 12 and the system control unit 34 shown in FIG.
[0035]
(Initial operation example 1)
An example of the control of the initial operation (track information read operation) when the optical disc 14 is loaded in the optical disc drive 10 is shown in FIG. In FIG. 1, each symbol represents the following.
SES: Current session number
SES-1: Current previous session number
TNO: Acquired track number
First TNO: First track number of the session
Last TNO: Last track number of the session
B0 pointer: Program area start time information given by TIME when the Q subcode of the lead-in area is ADR = 5 (mode 5) and POINT = B0
[0036]
The control shown in FIG. 1 is carried out spontaneously by detecting that the optical disk 14 is loaded in the optical disk drive 10 except for the portion for reading the path table. The portion for reading the path table is implemented in the form of data transmission in response to the command through the interface between the host computer 12 and the optical disk drive 14.
[0037]
When the optical disk 14 is loaded in the optical disk drive 10, the loading is detected by a detection means (not shown) in the optical disk drive 10 (S1). When loading of the optical disk 14 is detected, the optical pickup 18 is moved to the start position of the innermost lead-in area (fixedly determined as an area 46 to 50 mm from the center of the disk) (S2). Attempt to read the TOC information (S3). It is determined whether or not TOC information can be obtained (S4). If it cannot be obtained, the initial operation is terminated (S5). If the TOC information is obtained, the session number is set to 1 (S6).
[0038]
When the reading of the TOC information of the first session is completed, it is determined whether or not the multi-session recording is performed based on the information (S7). The multi-session recording can be understood from the fact that in the case of a CD-R disc and a CD-ROM disc, a POINT = B0 state exists when ADR = 5 (mode 5). In the case of a CD-RW disc, the TIME when ADR = 5 (mode 5) and POINT = B0 is a value other than FF: FF: FF. If it is determined that the recording is not multi-session recording, the optical pickup 18 is moved to the position where the first session path table is recorded (the start position of the program area), and the path table is read (S8). The process ends (S5). In the case of a single session, the initial operation is completed.
[0039]
If it is determined that the multi-session recording, 1 is added to the session number [S9]. Based on the start time information (B0 pointer (SES-1)) of the program area of the second session already obtained from the TOC information of the first session, a predetermined time before the start time (for example, 2 seconds before) A position (position considered to be in the lead-in area of the second session) is accessed, tracing is started from there, and an attempt is made to acquire the Q subcode of the second session (S10). This tracing is performed up to a position corresponding to the start time information of the program area of the second session (or up to a position ahead by a predetermined time). Based on the result of this trace, it is determined whether or not the Q sub-code has been acquired, and the format of the playback information is changed from the format of the lead-in area to the program area at the position corresponding to the start time information of the program area of the second session. It is determined whether or not the format has been switched to (S11). Whether or not the format of the reproduction information is switched from the format of the lead-in area to the format of the program area can be determined by, for example, the TNO of the Q subcode. That is, since TNO = 0 in the lead-in area and TNO ≠ 0 in the program area and the lead-out area, TNO changes from 0 to other than 0 at the position corresponding to the start time information of the program area of the second session. It can be determined by whether or not.
[0040]
If the Q subcode is not obtained as a result of the determination in step S11, or the position corresponding to the start time information of the program area of the second session is changed, the format of the reproduction information is changed from the format of the lead-in area to the format of the program area. If it is not switched, it is considered that the remaining area of the old session, etc., so the second session is determined as an invalid session, and the path table of the first session that has been determined to be valid so far is read. (S8), and the initial operation is finished (S5).
[0041]
When the Q subcode is obtained as a result of the determination in step S11, and the playback information format is switched from the lead-in area format to the program area format at the position corresponding to the start time information of the program area of the second session Accesses the start position of the lead-in area of the second session (position of the value obtained by subtracting 01: 00: 00: 00 from the start time of the program area of the second session) and attempts to read the TOC information (S12). First, it is checked whether or not an HF signal can be obtained (S13). If no HF signal is obtained, the second session is considered to be incomplete. The path table of the first session, which is the last session determined to be valid until then, is read (S8), and the initial operation is terminated (S5).
[0042]
On the other hand, when the HF signal is obtained, the Q subcode is read (S14). Then, the format of the read Q subcode is inspected (S15, S16), and in the case of the logical erase format or the format of the program area or the lead-out area, the second session is determined to be an invalid session, and the second session The track information acquired in the lead-in area is discarded (S17), the path table of the first session, which is the last session determined to be valid so far, is read (S8), and the initial operation is terminated (S5). .
[0043]
In other cases, that is, in the case of the non-erased format of the lead-in area, the TOC information is obtained as it is (S18). At that time, the continuity between each track number TNO included in the TOC information and the last track number of the first session before the TOC information is checked. That is, each time the track number TNO is first obtained from the TOC information, the track number is compared with the last track number of the first session (S19). If the track number TNO is equal to or smaller than the last track number of the first session, The second session is determined as an invalid session. In this case, the TOC information acquired in the lead-in area of the second session is discarded (S17), and the path table of the first session which is the last session determined to be valid is read (S8). The initial operation is terminated (S5).
[0044]
On the other hand, if it is determined that all track numbers TNO included in the acquired TOC information are larger than the last track number of the previous session (S20), the last track number of the first session and the second session number Comparison with the first track number is performed (S21). If the value obtained by adding 1 to the last track number of the first session is smaller than the first track number of the second session, the last track number of the first session and the first track number of the second session are discontinuous. Therefore, the TOC information acquired in the lead-in area of the second session is discarded (S17), and the path table of the first session, which has been determined to be valid so far, is read ( S8), the initial operation is terminated (S5).
[0045]
On the other hand, if the value obtained by adding 1 to the last track number of the first session is not smaller than the first track number of the second session, the last track number of the first session and the first track number of the second session are consecutive. Therefore, it is further checked whether or not the pre-gap length of the second session is the specified 00:02:00 (S22). This pregap length is obtained as a difference between the start time of the first track of the second session and the start time of the program area of the second session. The start time of the first track of the second session is the time when the POINT value is the same track number for the first track number of the second session given by POINT = A0 of the Q subcode of the lead-in area of the second session As PTIME. The start time of the program area of the second session is given by TIME when the Q subcode of the lead-in area of the first session is ADR = 5 and POINT = B0. Therefore, the difference between these PTIME and TIME is calculated, and it is checked whether or not it is the specified 00:02:00.
[0046]
As a result, if the difference is not 00:02:00, the second session is determined to be an invalid session, the track information acquired in the lead-in area of the second session is discarded (S17), and determined to be valid so far The first session path table which is the final session is read (S8), and the initial operation is terminated (S5). On the other hand, if the difference is 00:02:00, it is determined that the second session is valid, and the above determination operation is repeated for each session after the third session. As a result, all TOC information up to the previous session determined to be invalid (up to the final session determined to be valid) and the path table of the final session determined to be valid are acquired, and the storage device in the host computer 12 or the like Is remembered.
[0047]
When the initial operation is completed and access to an arbitrary track is instructed by an operation by the operator or the like, access to the corresponding track is executed based on the acquired information, and reading of the information on the track is performed. Done.
[0048]
In the embodiment described above, the position corresponding to the start time of the lead-in area of the next session is accessed based on the start time information of the program area of the next session read from the Q subcode of the lead-in area. The information necessary for valid / invalid determination and the track information are acquired from the lead-in area (after step S12 in FIG. 1). However, the present invention is not limited to this, and after the start position of the lead-in area of the next session. The information can also be obtained by accessing a suitably determined position (intermediate position in the lead-in area) before the start position of the program area of the next session.
[0049]
In addition, the control unit (system control unit 34, host computer 12) of the optical disc apparatus can perform the validity / invalidity determination by adding or replacing another condition to the method described in the above embodiment. For example, based on the start position information of the program area of the next session read from the Q subcode of the lead-in area, the track information is acquired prior to accessing the lead-in area of the next session and acquiring the track information (or (After acquisition) access the start position of the program area of the next session to determine the presence or absence of the HF signal, the presence or absence of the erase format, or the presence or absence of the format of the program area. If there is no program area format, the next session is determined as an invalid session. In addition, at this time, the length of the section of INDEX = 0 can be actually measured, and the validity / invalidity determination can be performed based on whether it is 00:02:00. If it is determined that the track information of the next session has already been acquired when it is determined to be invalid, the track information of the next session is discarded. If the track information of the next session is not acquired, the track information of the next session is not acquired. If it is not determined to be invalid, if the track information of the next session has already been acquired, the next session is further accessed on condition that other conditions are also satisfied. If it is before acquiring the track information of the next session, the start position of the lead-in area of the next session or an intermediate position in the lead-in area is accessed to acquire the track information of the next session and as necessary. To determine other conditions related to the next session.
[Brief description of the drawings]
FIG. 1 is a flowchart showing an embodiment of a track information acquisition method of the present invention.
FIG. 2 is a schematic diagram showing a division state of each area of an optical disc on which multi-session recording is performed.
FIG. 3 is a diagram illustrating a Q subcode format of a lead-in area according to a CD standard.
FIG. 4 is a diagram showing a Q subcode format of a program area and a lead-out area according to the CD standard.
FIG. 5 is a system configuration block diagram showing an embodiment of an optical disc apparatus according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10,12 ... Optical disk apparatus (optical disk drive, host computer), 14 ... Optical disk, 12, 34 ... Control part (host computer, system control part).

Claims (4)

  The start time information of the program area of the next session is read from the lead-in area of the session on the inner circumference side of the disk, and is defined as a position corresponding to the program area start time or a position before the program area start time. Access the position corresponding to the start time of the lead-in area of the next session or an appropriately determined position between these two positions, and determine whether the information read from the accessed position is configured in the logical erase format. An invalid session determination method for an optical disc in which the disc outer peripheral side is determined as an invalid session after the next session when the logical erase format is used. When the recorded information is read from the lead-in area on the innermost circumference of the disc and the information includes the start time information of the program area of the next session, it is defined as a position a predetermined time before the start time of the program area. The start time of the lead-in area of the next session is obtained, and a position corresponding to the lead-in area start time or a position determined after this position and before the start position of the program area is accessed, Read the recorded information of the lead-in area of the next session from the accessed position, repeat this operation to read the lead-in area of each session and sequentially acquire the table of contents information of the disc,
It is determined whether or not the information read from the accessed position is configured in the logical erase format. A method for acquiring track information of an optical disc acquired as information. 3. The track information acquisition method for an optical disc according to claim 2 , wherein after acquiring the table of contents information, the path table is acquired by accessing a position where the path table of the last session in which the table of contents information is valid is recorded.   At an appropriate time after the disc is loaded, the lead-in area on the innermost circumference of the disc is accessed and the recorded information is read, and it is determined whether the start time information of the program area of the next session is included in the information. If it is included, the start time of the lead-in area of the next session specified as a position before the program area start time is obtained or the position corresponding to the lead-in area start time or the position Thereafter, an appropriately determined position before the start position of the program area is accessed, the recorded information in the lead-in area of the next session is read from the accessed position, and this operation is repeated to repeat the lead-in of each session. The table of contents information is sequentially acquired by reading the area, and the lead-in area start time of the next session is acquired. When accessing an appropriate position or an appropriately determined position before the start position of the program area at or after the corresponding position, it is determined whether or not information read from the accessed position is configured in a logical erase format In the case of a logical erasure format, the optical disc apparatus includes a control unit that performs control to end reading and then acquire the table of contents information up to the previous session as valid information.

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