JP2009535754A - Method and apparatus for handling rewritable optical discs - Google Patents

Abstract

A method of handling a rewritable type optical disc includes a disc recognition step including a step of determining information on the type of the optical disc, a mounting step including a step of reading information on a logical disc structure, and the disc recognition step is successful. And a formatting step subsequent to the mounting step, including the step of formatting the optical disc if information regarding the logical disc structure cannot be read. This method allows the PC to reformat the optical disc when basic disc information is available.

Description

The present invention relates to a method for handling a rewritable type optical disc including identification of the type of optical disc and mounting a logical structure.
The present invention also relates to an apparatus and computer software for recording on a rewritable type optical disc.

  When an optical disc is inserted into the drive unit, several actions need to be performed successfully so that information can be read or recorded from the disc. First, the exact type of optical disc needs to be recognized so that the reader can adapt the reading and / or recording method to the type of optical disc. Second, for the disc, this step involves reading the logical file structure. If both steps are successful, the disk is made available for use by the end user. If an error is detected either during the disc recognition step or during mounting, the known drive reports to the disc on demand and the end user cannot use it.

  However, this is not attractive to the end user and does not make other disks available, and is interested in being able to use the disks.

  It is an object of the present invention to provide a solution to the above problem that allows a user to use a predetermined type of disk reported on demand. The object of the invention is reached by a method for handling a rewritable type optical disc according to the invention. In the method according to the present invention, the formatting step following the mounting step includes the step of formatting the optical disc when the type of optical disc is identified in the disc recognition step, but the information about the logical disc structure contains errors or reads. I can't. This is based on the insight that the disk does not mount because it cannot read a given logical disk structure and the disk should still be formatable. Formatting allows the reuse of an optical disc at the expense of losing all stored information, so it only requires the availability of information obtained during disc recognition and already exists on the disc No information about the logical disk structure to be used is required. While distinctions between different types of optical disks, such as between CD and DVD, are usually made by light beam parameters, further distinctions such as between DVD + RW, DVD-RW and DVD-RAM are recorded with read in area. Or from information prerecorded in wobble during manufacture. This is advantageous for reading information prerecorded in wobble because it does not require a function for recording data.

  In an advantageous embodiment, the method further includes a recovery step preceding the formatting step if the information about the logical disk structure includes an error, the recovery step being stored on the optical disc prior to the formatting step. Recovering at least a portion of the user data. Errors encountered during the mounting step are related to either errors in reading the disk management information or errors in reading the file system information. In the latter case, the file system can be partially mounted. In such a case, it is advantageous to recover the information stored in a properly mounted file.

  In an advantageous embodiment of the method, defect management is enabled during the formatting step. In general, the use of defect management is optional. However, in view of the fact that it is more likely than usual that the disk has an unusable area when the previous attempt to mount the disk fails, the use of defect management stores the data. Reduce the risk of errors when you do. Further, advantageously, the formatting step further comprises an authenticating step comprising checking an unreliable area of the optical disc. Authentication ensures that untrusted areas are identified before the disc is used.

  The present invention also includes an apparatus for recording a rewritable optical disk according to claim 6. The present invention also includes a computer program product that, when executed by a general-purpose processor, causes a recording apparatus to execute the method of claims 1 to 5.

  These and other aspects of the invention will be apparent with reference to the embodiments described below. The features and advantages of the present invention will be further described with reference to the following drawings.

  FIG. 1 a conceptually shows an optical disc 11 having a track 12 and a central hole 10. The track 12 is the position of a series of recorded marks representing information (marks to be recorded) and is configured according to a single spiral pattern that constitutes a substantially parallel track in the information layer. An optical disc includes one or more information layers of a recordable type. Known examples of rewritable optical discs are CD-RW, DVD +/− RW, DVD-RAM or BD-RE. For example, further details regarding the physical structure and address information of DVD +/− RW optical discs are found in the cited examples ECMA-337 and ECMA-338, respectively. Information is represented in the information layer by recording optically detectable marks along the track, for example crystalline or amorphous marks in phase change material. The track 12 on the optical disc is indicated by a pre-embossed track structure provided during the manufacture of the blank optical disc. The track structure is constituted by guide grooves that allow the read / write head to follow the track during scanning.

  The track structure of a recordable disc includes variations of physical parameters generally known in the art that are in the form of periodic radial displacement of the groove from the average centerline. The periodic wobble is further modulated so that further information such as a physical address indicating the location of the unit of information is stored. The information further includes a specific synchronization mark, which places the start of such an information block. The location information is encoded in a group that includes a predetermined number of modulated wobbles. However, information encoded with wobble is not limited to address information. For example, in the case of CD-RW, the following information is stored in the wobble. Time information (physical address), write power at different speeds, start time at lead-in, lead-out, speed range. For DVD + RW discs, the stored information includes physical address, disc category (eg DVD + R, DVD + RW), disc size and maximum transmission rate, disc structure (eg recordable layer, rewritable layer), recording density, data zone Includes assignments (data zone start and end addresses), disk application code, disk ID, manufacturing ID or write strategy parameters (speed range, write / read power at several speeds). In the case of the BD_RE disc, there is a pre-recorded area known as the PIC area, and the following information is stored. Media type, write strategy at different speeds and alternative strategies, speed range, read power at different speeds, disk size, number of layers, data zone assignment (data zone start and end addresses). The information is repeated 5 times for robustness. The previous information stored in the wobble is information on how to handle the optical disc, and does not give information on actual recording on the disc.

  The optical disc 11 is intended to hold user information according to a standardized format that can be played back by a standardized playback device. The recording format includes the way information is recorded, encoded and logically mapped into the recording space provided by the track 12, and will be described with reference to FIG. 1b. The recordable space is usually divided into a lead-in area (LI), a data zone (DZ) for recording user data, and a lead-out area (LO). The lead-in area (LI) typically includes an area 13 in which basic disk management information is stored and a disk description area 14 in which information on how to physically access the data zone is provided. For example, the basic disc management information corresponds to a table of contents in the CD system or to a format disc control block in the DVD system. Further, at the logical level, the user data in the data zone includes file management information such as ISO 9660 used in the CD system available as ECMA-119 and UDF used in the DVD system available as ECMA-167. Configured according to the file system. Such file management information is mapped to a predefined position 15 on the optical disc 11 which is usually in the lead-in area (LI) or immediately after the lead-in area. The user information recorded in the data zone (DZ) is further configured according to an application format including, for example, a predefined file and directory structure.

  FIG. 2 conceptually shows a recording device for writing information on the optical disc 11, as illustrated with reference to FIG. 1a.

  The recording device is provided with recording means for scanning a track of the optical disk. The recording means is a positioning unit for roughly aligning the head 18 in the radial direction of the drive unit 16 and head 18 that rotate the optical disk 11 and the track. A unit 21 and a control unit 17 are included. The head 18 has a known type of optical system that generates a radiation beam 20 that is guided through an optical element that focuses the radiation beam 20 onto the radiation spot 19 of the track 12 of the optical disk 11. The radiation beam 20 is generated by a radiation source, for example a laser diode. The head further includes a focus actuator that moves the focal point of the radiation beam 20 along the optical axis of the beam, and a tracking actuator (not shown) that precisely positions the radiation spot 19 in the radial direction at the center of the track. The tracking actuator has a coil that moves the optical element in the radial direction or is alternatively configured to change the angle of the reflective element.

  For the read information, the radiation reflected by the information layer is, for example, 4 at the head 18 generating a read signal and further detector signals such as tracking error signals and focusing error signals that control the tracking and focusing actuators. It is detected by a usual type of detector such as a quadrant diode.

  To record information, the radiation beam 20 is controlled to form optically detectable marks in the recording layer. For this reason, the recording apparatus has write processing means for processing the input information and generating a write signal for driving the head 18, and this write processing means includes the input unit 23, the formatter 24, and the modulator. 25, data processing means.

  The control unit 17 is configured to control recording of information on the optical disc 11 and reading of information from the optical disc 11 and to receive a command from a user or a host computer. For this purpose, the control unit 17 has a control circuit such as a microprocessor, a program memory and a control gate for executing the procedure described below with reference to FIG. 3, for example. The control unit 17 is realized as a state machine by a logic circuit. The control unit 17 is connected to the input unit 23, formatter 24 and modulator 25, to the drive unit 16, and to the alignment unit 21 via a control line 22 such as a system bus.

  The input unit 23 receives user information and preprocesses it. For example, when processing audio-video information, the input unit 23 has compression means for compressing input signals such as analog audio and / or video, or digital uncompressed audio / video. Suitable compression means are described for audio in WO98 / 16014-A1 (PHN16452) and for video in the MPEG2 standard (ISO-IEC13818). The input signal may alternatively already be encoded. The output of the input unit 23 is sent to the formatter 24 in order to format the data in accordance with the recording format by adding control data, for example, adding an error correction code (ECC) and interleaving. For computer applications, the unit of information is interfaced directly to the format 24. Formatted data from the output of the formatter 24 is passed to a modulation unit 25, which has a channel coder, for example, to generate a modulated signal that drives the head 22. Furthermore, the modulation unit 25 has a synchronization means for including a synchronization pattern in the modulated signal. The formatted unit provided at the input of the modulation unit 25 contains address information and is written to the corresponding addressable location on the optical disc under the control of the control unit 17. The control unit 17 is configured to record and read position data indicating the position of the recorded information volume.

  During the recording operation, marks representing information are formed in an optical disk shape. Marks are obtained when recording with a material such as a die, alloy or phase change material, for example, in the form of areas having a reflection coefficient different from their surroundings, or when recording with a magneto-optical material. Their surroundings are in an optically readable form, such as in the form of areas with different magnetization directions. The writing and reading of information for recording on an optical disc and the usable formats, error correction and channel coding rules are known in the art, for example from the CD system (IEC 908).

  For reading, the read signal is processed by a read processing unit having a demodulator 26, a deformer 27, and an output unit 28 to output information. The functions of the demodulator 26, deformer 27 and output unit 28 are controlled by the controller 17. Accordingly, the reading means for reading information includes the drive unit 16, the head 18, the alignment unit 21, and the reading processing unit.

  FIG. 3 illustrates by way of a flow diagram a method for handling an optical disc according to the invention.

  When an optical disk is inserted into the apparatus, first, a disk recognition step 40 is executed (DSC_REC). This step is known in the art, and in a first sub-step, a first parameter of the reflected radiation (eg focus) parameter to determine whether the optical disc is of CD, DVD or BD type. Includes decisions. After the disc type is identified, further basic disc information is read so that basic read / write parameters and lead-in area, data zone and lead-out locations are determined. The basic disc information is read from information encoded in wobble or read from information recorded in the lead-in area.

  In step 41, it is checked whether the disc has been successfully recognized. If disc recognition fails without basic information about the disc being available, the disc is ejected as damaged at step 42.

  If the disc recognition is successful, the disc management information recorded in the lead-in area is read in the first sub-step, followed by the mounting step 43. This information comprises information that allows access to the logical layer. For example, in a CD-RW system this corresponds to reading a table of contents (TOC), in a DVD-RW system this corresponds to reading a formatting disc control block (FDCB) and in a BD-RE system. This corresponds to reading the (temporary) defect management area (T) DMA. The information present there indicates the format of user data on the disc such as UDF or ISO9660, in which case the file information table is located. In the next sub-step, the file information table is accessed and the mounting of the disc is terminated.

  In step 44, it is checked whether the disc mounting is successful. If the disc has been successfully mounted, the end user uses the disc in step 45, for example by reading and / or recording data.

  Disk mounting is unsuccessful due to the following types of errors: Errors are encountered by reading the basic disc management information so that no information is available in the mounting step regarding the type of format the user has with respect to the disc, or where the file allocation information is recorded on the disc. Errors are encountered in reading file allocation information.

  When no error is encountered, known optical drives eject the disk as damaged. However, in the method and apparatus of the present invention, if the disc recognition succeeds but the disc mount fails, the rewritable type disc is reformatted in the format step 46 (FORMAT) instead of being taken out as damaged. It is possible to be done. This is based on the insight that only basic disc identification information that can be extracted from the wobble is needed to format the disc. Note that when the latter type of error is encountered, the recovery step (RECOV) precedes formatting as will be detailed later.

  The process of formatting an optical disc is known and several options are available. The process known in the art as regular formatting is the traditional way of physical formatting used for optical discs such as CD or DVD. After the regular for matching process, the disc is fully formatted at the physical level. The formatting process consists of recording the lead-in area (LI) and writing to the data zone (DZ). Includes lead-out area writing (LO) and, optionally, data zone authentication, and defect management initialization if defect management is to be used. Note that defect management may be operated outside the apparatus, such as by a computer operating system. A second type of formatting process is known in the art as background formatting, which is a formatting process that is performed in the background during use of the disc in the recorder. After the background formatting process is completed, the disc is completely physically formatted at the physical level. User data is recorded on the disk during the background formatting process. The background formatting process includes the following steps: Initialization of defect management, optional data zone de-icing, lead-in and lead-out zone finalization, (if applicable) early removal Termination, restart of background formatting on early ejected disk, and authentication (optionally selected by host computer).

  In general, background formatting is seen as a very time efficient solution for users. This is because during the initialization phase of the background formatting process, only a minimal amount of data is recorded on the disc, after which the disc can be used by the application / user. A disk for which the background formatting process is active is further formatted by the device in the background at the moment the application does not access the disk.

  In view of the fact that it is expected that the disk will almost certainly have the most unusable area when a previous attempt to mount the disk fails, the preferred embodiment of the present invention provides for background formatting. Instead, regular formatting is used. This allows a full authentication step 48 (VERIF) to be performed before the disk is used. Authentication is the process of reading and checking all information blocks in the data zone of the disk. If it is determined that the information block is unreliable, defect management is employed to avoid using the information block for recording user information.

  With regard to defect management, for example, regular disk format corresponding to normal user data size and normal defect replacement area, frequently used disk format corresponding to small user data size and large defect replacement area, and the largest Different possibilities are available, such as the size of the user data and the less used disk format corresponding to the smallest defective replacement area. In the preferred embodiment of the present invention, when the previous attempt to mount the disk fails, the frequently used disk format is used in view of the fact that the disk has an almost unusable area. The

  When reading the disk management information, ie the type and location of the file management system, in an embodiment of the method, the formatting step is preceded by a recovery step 47 (RECOV). This occurs when an error is encountered while reading the file system information so that the file system is partially mounted. This is realized by mounting the disk as a read-only disk. In such a case, the information located in the properly mounted file is recovered. Further, when the drive determines the logical disk layout of the disk, but the replacement area used by the defect management system is completely full, in the method according to the present invention, in the recovery step 47, the disk is read. Mounted as an online disk. After mounting, the user chooses to reformat the disk, including bad areas, or decides to perform an authentication step. This was due to dirt and oil being present in the areas of the disc where some bad areas were present and the disc was cleaned, including some areas marked as defective being unusable. Based on the insight that there is a possibility. If successful, the new replacement area becomes available so that the disc can be remounted as a rewritable disc.

  With respect to implementing the present invention in an apparatus, disc recognition, disc mounting, formatting, reading and recording of information on such rewritable optical discs are known. In a preferred embodiment, the control unit 17 is enabled to handle a rewritable type optical disc according to the new method described above, for example by suitable firmware. In an alternative embodiment, a determination unit 29 connected to the reading and recording means via the control line 22, further comprising a determination unit 29 connected to or incorporated in the control unit 17. May exist. The determination unit 29 makes a determination based on the output of steps to be performed such as disk recognition and disk mounting steps, formatting and / or authentication and / or recovery. Optionally, if the device is an optical disk drive in a personal computer, the present invention is implemented in software, allowing the drive according to the present invention to be operated. Such software provides an option to ask the user if they are interested in either reformatting the disc or inserting a new disc if the disc recognition is successful and the disc mount is unsuccessful. May include.

  The above-described embodiments are meant to illustrate rather than limit the present invention. Those skilled in the art can design many alternative embodiments without departing from the scope of the claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. Use of the verbs “comprise” and “include” and their derivatives does not exclude the presence of elements or steps other than those stated in a claim. The articles “a” and “an” preceding an element do not exclude the presence of a plurality of such elements. The present invention is implemented by several individual elements and by a suitably programmed computer. The computer program may be stored / distributed on a suitable medium such as optical storage, or supplied with hardware components, but in other forms such as distributed over the Internet or wired or wireless telecommunication systems. May be dispersed by In the system / device / apparatus claims enumerating several means, several of these means may be embodied by one and the same item of hardware or software. The fact that certain means are recited in mutually different dependent claims does not indicate that a combination of these means cannot be used.

It is a figure which illustrates an optical disc notionally. It is a figure which shows notionally the optical drive with which this invention is implemented. It is a figure which illustrates the method of handling the optical disk based on this invention with a flow diagram.

Claims (8)

A method of handling a rewritable optical disc,
A disc recognition step including determining information regarding the type of optical disc;
A mounting step including reading information about the logical disk structure;
Including the step of formatting a disc when the type of the optical disc is determined in the disc recognizing step and the information about the logical disc structure contains an error or the information cannot be read. A formatting step following the mounting step;
A method comprising the steps of: And further comprising a recovery step preceding the formatting step, comprising recovering at least a portion of user data stored on the optical disc prior to the formatting step if the information regarding the logical disk structure includes an error.
The method of claim 1. The defect management is enabled during the formatting step,
The method of claim 1. The formatting step further includes a confirmation step comprising checking an unreliable area of the optical disc.
The method of claim 3. The disc recognition step includes a step of reading prerecorded information stored in a wobble of a track of the optical disc,
The method of claim 1. Reading means for reading information from the optical disc;
Recording means for recording information on the optical disc;
Control means for controlling the reading means and the recording means to perform the method according to any one of claims 1 to 5,
A device for recording a rewritable type optical disc having   A computer program that, when executed by a general-purpose processor, causes a recording apparatus to execute the method of claims 1 to 5.   A recording medium comprising the computer software according to claim 7.

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