JP2001351335A - Optical recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To evade a defective closed session operation due to vibrations, impacts, etc., and to eliminate the unnatural feeling of a user performing the close session operation. SOLUTION: A write once recording medium 25 writes and reads data on the basis of a file system based on UDF and has a disk shape. A 1st session is previously closed in the medium 25 to record irreducibly necessary data or to record the static images such as sample images and the moving images serving as advertisement in a state that they undergo each prescribed compression processing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical recording medium on which data is written and / or read using a laser beam, and more particularly to an optical recording medium on which an initial closed session operation has been performed.

[0002]

2. Description of the Related Art A so-called CD to which optical reading is applied.
(Compact Disc).
Recorded as an optical disk. ) Has a large storage capacity and allows random access. In addition, since optical reading is non-contact, there is no danger such as head crash or wear and damage due to reading as compared with a contact type recording medium such as a magnetic tape. Also, because the disc surface is sturdy,
There is less danger of accidental data loss. An optical disc having many advantages as described above is an excellent recording medium as a memory around a computer and in data production and data storage.

In recent years, CD-Rs (Compact Disc-Rec
A recording / reproducing apparatus using a write-once optical disc called ordable) has been developed. Some of these CD-Rs can easily be written to all standard formats used on compact discs, such as CD-ROM, CD-ROM / XA, CD-I, and CD-DA. Some can. CD-Rs are mounted on electronic devices instead of conventional magnetic tapes, magnetic disks, etc., to record and / or record data.
Or, it is being used as a recording / reproducing device for reproducing.

In a CD-R, since recording data is additionally written and added, in a recordable state, table of contents information (hereinafter, referred to as a CD-ROM or the like) recorded on an inner peripheral portion of the disc is recorded.
TOC: Described as Table Of Contents. ) Is not described.

That is, in a CD-R, when data cannot be added any more, a finalizing process (closed session operation) is performed for the first time to write TOC information as table of contents information of a recording medium. It has become.

Therefore, when the CD-R is not finalized (recordable), the CD-R refers to the provisional TOC written in the PMA (Program Management Area) of the recording medium to determine the start position of the additional recording. And I am searching for the recording position of the playback data. Since the playback device for playing the CD-ROM cannot read the provisional TOC described in the PMA, it is not possible to read a write-once recording medium that has not been finalized by a playback device that supports the CD-ROM. Impossible. Therefore, it is necessary to perform a finalizing process in order to enable reproduction by a reproducing apparatus compatible with a CD-ROM.

Hereinafter, a finalizing process (closed session operation) performed in the conventional recording apparatus will be described with reference to FIG.

[0008] When the user instructs execution of the closed session operation by an operation from the user, in step S20, the recording apparatus reads temporary table of contents information (hereinafter referred to as "PMA") from a program management area (PMA) of the recording medium. , TOC: TableOf Contents).

Next, in step S21, a regular TOC is created based on the information of the recorded area.

Next, in step S22, it is determined whether or not the recording area of the recording medium is the first session.

In the case of the first session, writing of closed session data corresponding to the first closed session operation is performed. In step S23,
Zero out the 13.8 Mbyte lead-out area.

Subsequently, in step S24, about 20 Mb
The regular TOC is repeatedly written in the lead-in area of yte, and when the writing is completed, the closed session operation is completed.

On the other hand, in step S22, if the recording area of the recording medium is not the first session, writing of closed session data corresponding to the second and subsequent closed session operations is performed. In step S25, a lead-out area of about 4.6 Mbytes is padded with zeros.

Subsequently, in step S26, about 9.2M
Write the regular TOC repeatedly to the byte lead-in area,
When writing is completed, the closed session operation is completed.

In the closed session operation, about 13.8 Mbytes of closed session data, which is about 9.2 Mbytes in the lead-in area and about 4.6 Mbytes in the lead-out area, are written.

In particular, in the first closed session operation, the standard specifies that about 33.8 Mbytes of data including about 20 Mbytes in the lead-in area and about 13.8 Mbytes in the lead-out area are written.

In a conventional recording apparatus, the above-described finalizing process (closed session operation) is performed on a write-once recording medium, so that the recording apparatus can reproduce the data even on a CD-ROM compatible reproducing apparatus.

[0018]

However, in a closed session operation for writing closed session data on a recording medium, in a normal recording apparatus driven at 1 × speed, about 8/8 minutes is required for the first closed session operation.
It takes about 1 minute and 30 seconds for 0 seconds, the second and subsequent closed session operations. In the conventional recording apparatus, in the closed session operation as described above, particularly, the recording capacity of the data for the first closed session is large, and accordingly, the time required for the closed session operation becomes long.

During long closed session operations, it is sometimes difficult to keep the recording device stable. The shock or vibration applied to the recording apparatus during this period not only causes a failure of the closed session but also causes a problem in data recorded on the recording medium.

Further, since there is a difference in the required time between the first closed session operation and the second and subsequent closed session operations, the user using the recording device feels uncomfortable with the difference in the required time, and It may be erroneously recognized as a failure or malfunction.

Therefore, the present invention has been proposed in view of such a conventional situation, and data for the first closed session is recorded in advance, thereby avoiding a problem of closed session operation due to vibration, impact, and the like. It is another object of the present invention to provide an optical recording medium that can eliminate a user's discomfort in performing a closed session operation.

[0022]

In order to achieve the above-mentioned object, an optical recording medium according to the present invention performs a closed session operation for making written data readable by another reproducing apparatus. The recording area is divided for each set of data and recorded, and the data amount of the closed session data written by the first closed session operation is larger than the data amount of the closed session data written by the second and subsequent closed session operations. An optical recording medium having a large size, wherein data for the first closed session is recorded.

Here, in the area where the first closed session operation has been performed, only the minimum data necessary for the closed session operation is recorded, and still picture information and / or moving picture information are recorded in advance. It is mentioned. Further, it is a write-once and / or rewritable recording medium.

[0024]

Embodiments of the present invention will be described below in detail with reference to the drawings.

A digital still camera employing the optical recording medium according to the present invention as a recording medium is a UDF (Universal Dis
k Format), based on a file system that conforms to the file system, writes captured image data to a write-once recording medium and reads image data from the recording medium. In this case, the finalizing process (closed session) for enabling the reproduction by the reproduction apparatus of the first type is controlled according to the conditions. Controlling the closed session operation includes starting the closed session operation after a predetermined time has elapsed since the user selected execution of the closed session operation, and displaying the remaining time until the start of the closed session operation at that time. When the execution of the closed session operation is selected by the user, notification of installation on a stable object is performed, and when the vibration detection unit detects vibration, the closed session operation is not started. .

Next, a digital still camera shown as an embodiment of the present invention will be described in detail.

First, UDF (Universal Disk Format) means CD-R (Compact Disc-Recordable), WORM (Write-O
nce Read-Many optical disk), CD-R / RW (Compact Dis
c-Recordable / Rewritable), MO (Magnet Optical Dis
k), one of the definitions for describing the character codes of file names and file attributes that can be used mutually for various media such as DVD (Digital Versatile Disk) and OSTA.
(Optical Storage Technology Association).

That is, the UDF is a file system that can be written from any OS and the written file can be reproduced on any OS without a special reader program.

In UDF, a main data structure is a file entry information control block (ICB).
k) is used. In UDF, every file and directory has its own ICB. In the embodiment of the present invention, a file storing actual data such as image data of a captured image is generally written before an ICB that defines the file. When placed on the (data stream), the ICB can include a list of those extents.

In UDF, VAT (Virtual Allocation Tabl)
Using a mapping table called e), a sequential number (virtual address) for a virtual reference is assigned to each file. Whereas a file system conforming to the international standard ISO9660 refers to each file or directory on a recording medium directly by a logical address, UDF
Is referred by the virtual address as described above. VAT
Can be placed anywhere in the truck,
Further, the VAT is referred to by a VAT ICB indicating the location of the VAT.

In the UDF, it is determined that the VAT ICB is located at the last physical address recorded on the recording medium. The VAT is divided and arranged on a plurality of extents, but the VAT ICB includes a VAT extent list. Thus, in a UDF, if a file is modified in any way, the entire set of file pointers does not need to be changed, and eventually only the VAT ICB can be reached to the changed file .

In a UDF-compliant file system, the structure of a unit (hereinafter, referred to as a volume) for managing a detachable recording medium that accommodates a file or the like is as shown in FIG.

In a file system conforming to the UDF, a BEAD (Beginning) in an extended area recorded after 16 sectors when the beginning of a session is set to 0 sector.
Extended Area Descriptor) and TEAD (Terminating E)
VSD (Volume S) sandwiched between xtended Area Descriptor
tructure Descriptor) contains information for recognizing the UDF file system.

In a UDF-compliant file system, an AVDP (Anchor Volume) in which an optical head reads first to reach a file in a state where data is written to a recording medium and before closing a session.
Descriptor Pointer). AVDP has a logical block number (LBN) of 512 when the beginning of a session is 0 sector.
It is described in the area of the sector.

That is, if an AVDP exists in the sector 512, it is understood that the AVDP is recorded based on a UDF-compliant file system. AVDP is composed of LBN = 256 sectors and LBN =
(LBN of last write sector) Described in two sectors out of -256 sectors. After the closed session operation, the AVDP described in the sector 512 is not used for reading. AVDP stands for Volume Descriptor (VDS: Vol
Described as ume Descriptor Sequence. ). The VDS group is described from sector 512 onward.

The VDS is a descriptor indicating information on the contents of the volume structure. The VDS has a basic volume descriptor and a logical volume descriptor (hereinafter referred to as LVD: Logical Volume Descriptor).
Write as ume Discription. ), Volume information such as an application volume descriptor, a virtual partition descriptor, and a real partition descriptor, and partition information.

There are two partitions, a real partition and a virtual partition. The real partition contains the actual logical address of the data recorded on the recording medium. On the other hand, the virtual partition is a table based on the virtual address of the data, and is a division of the area when the entire recording area of the recording medium is remapped from the physical address to the virtual address. The virtual partition is determined by VAT.

Further, two descriptors indicating a real partition and a virtual partition are placed in the VDS.
If the partition number is 0, the file system refers to the real partition, that is, the actual logical address, and if it is 1, the file system refers to the virtual partition (VAT).

The LVD in the VDS indicates a set of file set descriptors (hereinafter, referred to as FSDS: File Set Descriptor Sequence), that is, a set of file sets existing in the volume. Each FSDS is RDICB
(Root Directory Information Control Block), and the RDICB contains information such as specific directory names and file names.

A UDF-compliant file system suitable for packet writing has two unique data structures. File Entry ICB (File Entry ICB) for identifying each file existing in the file system
And a file identifier (FID)
Descriptor. ). The FID indicates the physical address of the file entry ICB. Or, via VAT,
Indirectly points to the file entry ICB.

The directory referred to by the RDICB is configured as a table in which related FIDs are collected. The file entry ICB contains all extent lists, dates, file attributes, and the like of the stored file. Therefore, the content of this file entry ICB is a physical address that may change when the file is changed or edited.

The FID points to the file entry ICB, and the file entry referenced by the file entry ICB points to an actual file. Since a directory is a type of file, a file entry can also point to a directory. Thus, the file system conforming to the UDF has a tree-like hierarchical structure.

As described above, the root directory can be referred to by RDICB. In the root directory, the FID for referring to the file entry ICB
Or contains an FID pointing to the directory entry ICB.

The FID has information such as “partition 1 / block 200”. If the partition is 1, since it is a virtual partition, the file system directly accesses the logical address to search for a file.
Do not go to 200. Instead, it will first reference the VAT and point to the logical address via the VAT.

As a result of the above file system, the UDF executes a sequence schematically shown in FIG. 2 in order to seek a file.

The optical head first reads the last area of the recorded area of the disk. Here is VAT ICB
Is described. VAT is read from VAT ICB.

Subsequently, the optical head refers to the AVDP in the sector 256. Next, VDS described in AVDP is referred to.

From the VDS, it is determined whether the partition is a real partition or a virtual partition.

Further, the FSDS is referred from the VDS. The FSDS indicates the RDICB, and the RDICB indicates the root directory. The root directory contains an FID indicating the ID of each file.

Finally, if the partition flag of the VDS of the root directory constituted by the FID is a real partition, the physical address of the file entry ICB is directly referred to. If the flag is a virtual partition, File entry ICB via VAT
To the desired file.

By providing a VAT between the FID and the file entry ICB, even if the file entry ICB is rewritten, the file entry ICB is replaced on the VAT to virtually replace the file entry ICB.
It can be treated as if the ICB was rewritten.

Therefore, even if the location of the file entry ICB is changed due to, for example, changing the contents of the root directory, it is not necessary to rewrite the FID if the VAT is changed.

In the file system conforming to the UDF, by performing the above-described seek operation, it is possible to treat a sequential write recording medium as if it were a random read / write recording medium.

Next, one specific example of a digital still camera employing the optical recording medium according to the present invention as a recording medium is as follows.
This will be described with reference to FIG. The digital still camera, for example, writes and reads data to and from an optical recording medium. Here, the optical recording medium is a write-once recording medium, and is a so-called CD having a disk shape.
-R (Compact Disc-Recordable).

The digital still camera 1 includes an image pickup section 10 for picking up an image of a subject, and an image signal processing section 1 for converting an image signal from the image pickup section 10.
1, a display unit 12 for displaying operation information for operating the digital still camera 1, an image signal, and the like, and an OP (Opti) for writing and / or reading from a recording medium described later.
cal Pickup) section 13, an RF processing section 14 for performing RF processing on a read signal, a servo signal processing section 15 for generating a servo signal from each signal from the RF processing section 14, and a servo signal processing section 1.
An analog filter processing unit 16 that generates an analog signal for controlling each driver based on the signal from the control unit 5;
A signal processing unit 17 that processes a read signal from a recording medium described later, a spindle driver 18 that controls the rotation of a spindle motor, a sled driver 19 that controls the operation of a sled motor, and swings the objective lens of the OP unit 13 A tracking driver 20 for controlling the focus of a beam by moving an objective lens of the OP unit 13 in the vertical direction with respect to the disk-shaped recording medium; a spindle motor 22 for driving the disk-shaped recording medium; Motor 13 for moving the recording medium 13 in the radial direction of the recording medium
And a control unit 24 that controls each unit. When writing of captured image data is performed on the recording medium 25 on which the finalization process (closed session operation) has been completed for the first time, the second and subsequent closed This is executed from the session operation.

The imaging section 10 includes a lens section for capturing an image of a subject and a charge-coupled device (hereinafter, referred to as a CCD) for generating an image signal.
It is written. ), A sampling / hold (hereinafter, referred to as S / H) circuit, and an A / A for converting an image signal into a digital signal.
And a D conversion circuit. The CCD generates an image signal from a subject image from a lens unit, and supplies the generated image signal to an S / H circuit. The S / H circuit samples and holds the image signal from the CCD, and then supplies it to the A / D conversion circuit. The A / D conversion circuit converts the image signal from the S / H circuit into a digital signal and supplies the digital signal to the image signal operation processing unit 11.

The image signal arithmetic processing unit 11 is controlled by the CPU to convert the digital image signal from the imaging unit 10 into RG signals.
It performs image processing such as color standard form conversion from B signal to color difference / luminance signal, white balance processing, γ correction, reduced image processing, JPEG compression processing and the like. The processed image signal is stored in an SR
After temporarily stored in the AM, it is supplied to the signal processing unit 17. Further, the image signal arithmetic processing unit 11 supplies the processed image signal to the display unit 12.

The display unit 12 is, for example, a liquid crystal display (LCD), and displays an image signal from the image signal processing operation unit.

The OP (Optical Pickup) unit 13 includes an objective lens, a laser diode (LD), a laser diode driver, a photodetect IC (Photo Detect IC), a half mirror, and the like. Output to When recording on the recording medium 25,
The recording medium 2 is based on a laser blinking / driving signal (DECEFMW) from the signal processing unit 17 necessary for pit formation, a signal (write strategy) indicating an optimum value of laser intensity and blinking, and the like.
5 is written.

The RF processing unit 14 samples and holds the eight signals consisting of the beam signal detected from the OP unit 13 and the side-and-main signal, performs an arithmetic processing, and performs an arithmetic processing. From a predetermined signal, signals such as FE (focus error), TE (tracking error), MIRR (mirror), ATIP (Absolute Time In Pregroove), and a read main signal are generated. The RF processing unit 14 outputs the FMDT (Frequency Modulation Data), the FMC
Outputs K (Frequency Modulation Clock), TE, and FE to the servo signal processing unit 15, and optimizes the laser intensity detected by test writing (OPC: Optical Power Calibration)
The signal and the laser blinking / driving signal are output to the signal processing unit 17 and the MIRR is output to the control unit 24.

The servo signal processing unit 15 receives the FMDT (Frequency Modulation Data) and FMCK (Frequency
ency Modulation Clock), TE, FE, and control unit 2
4 to generate signals for controlling various servos unique to the optical disk, and output the signals to the analog filter processing unit 16.

The analog filter processing section 16 generates analog signals from various servo control signals from the servo signal processing section 15 and outputs the analog signals to the spindle driver 18, thread driver 19, tracking driver 20 and focus driver 21.

The signal processing unit 17 is controlled by the control unit 24 and receives the OPC and DECFFM from the RF processing unit 14 to perform processing such as CIRC decoding and encoding, write strategy, ADdr decoding, asymmetry calculation, and running OPC. Do. When writing data to the recording medium, a signal such as a laser blinking / driving signal and a signal indicating an optimum value of the laser intensity is output to the OP unit 13.

The spindle driver 18 controls the rotation of the spindle motor 22 based on a signal from the analog filter processing section 16.

The thread driver 19 is controlled by the thread motor 23 based on a signal from the analog filter processing unit 16.
Control the thread behavior of

The tracking driver 20 oscillates the OP unit 13 based on a signal from the analog filter processing unit 16 to control the position of a beam spot irradiated on the disk surface of the recording medium 25.

The focus driver 21 controls the focus adjustment of the laser by moving the OP unit 13 in a direction perpendicular to the disk surface of the recording medium 25 based on the signal from the analog filter processing unit 16.

The spindle motor 22 rotates the recording medium based on a signal from the spindle driver 18.

The thread motor 23 performs a thread operation of the OP unit 13 based on a signal from the thread driver 19.

The control unit 24 has a program memory for storing programs for performing various processes, and an SRAM as a work area for temporarily storing the VAT ICB and various data.
(Static Random Access Memory) and a CPU, and determines whether or not a first session of the recording medium 25 described later is closed, and controls writing and reading of data to and from the recording medium 25.

The recording medium 25 is a write-once recording medium for writing and reading data based on a UDF-compliant file system, and has a so-called disk shape.
CD-R (Compact Disc-Recordable).

In the recording medium 25, the first session is closed in advance, that is, the first closed session operation has been executed, and the first session has recorded the minimum necessary data, And a moving image as a publicity advertisement are recorded in a state where predetermined compression processing has been performed.

FIGS. 4 and 5 are cross-sectional views of the recording medium 25. FIG. FIG. 4 shows a cut surface when the recording medium 25 is cut perpendicular to the disk surface. FIG. 5 is an enlarged view of the inner peripheral side of the disk in the sectional view of FIG.

As shown in FIG. 4, the recording medium 25 has a power calibration area (PC).
A) and the program management area (Program Manegem)
entArea: PMA) and Lead-in Area
And an information area (Imformation Area).

Further, as shown in an enlarged view of FIG. 5, a power calibration area includes a test area as an area for actually performing test writing, and a count area for counting the start position and the number of times of test writing. And

The hatched areas in FIGS. 4 and 5 indicate that recording has been completed.

The test area is divided into 100 partitions, and this partition is specified by a relative time from the start time of the lead-in area. Each partition consists of a minimum of one frame.
It is divided into sub-partitions, and one sub-partition is further divided into three frames. The laser output is adjusted by performing test writing immediately before writing using this subpartition.

In the digital still camera 1 configured as described above, the operation of each component when reading a signal recorded on the recording medium 25 will be described.

The light of the laser diode reflected from the disk surface of the recording medium 25 is read by the lens optical system of the OP unit 13. Light from the lens optics is converted to PDIC (Photo De
tectIC), is converted into an electric signal, is sampled and held in the RF processing unit 14, and focus error (FE), tracking error (TE), mirror (MIRR), ATIP (Absolute Time In P
regroove), a signal such as a read main signal is generated by arithmetic processing.

First, the focus error obtained by the RF processing unit 14 is determined by the servo signal processing unit 15 (Digital Servo
After the characteristic is adjusted by the processor, the signal is input to the focus driver 21 through the analog filter processing unit 16 (Analog Filter Block). Focus driver 2
1 moves the lens drive focus coil (not shown) of the OP unit 13 in the vertical direction to correct the focus shift.

Similarly, the tracking error obtained by the RF processing unit 14 is determined by the servo signal processing unit 15 (Digital Serv.
o Processor) to extract the AC component and apply digital filter processing. Thereafter, the signal passes through the analog filter processing unit 16 and is input to the tracking driver 20.
The tracking driver 20 finely moves the lens drive tracking coil of the OP unit 13 in the radial direction to correct the tracking deviation.

The tracking error obtained by the RF processing unit 14 is subjected to a DC component extraction by the servo signal processing unit 15 and digital filter processing. After that, the thread driver 1 passes through the analog filter processing unit 16.
9 is input. The thread driver 19 operates the thread motor, moves the entire OP unit 13 in the radial direction of the recording medium, and corrects the deviation of the thread operation. During the seek operation, the sled motor is forcibly driven by intentionally applying the sled control voltage from the outside.

As described above, the tracking operation in which only the lens is finely moved in the radial direction based on the AC component of the tracking error is performed, and the sled operation for moving the entire OP unit 13 in the radial direction based on the DC component is performed. Will be

Since the detection signal (mirror) of the change in the reflectance of the recording medium output from the RF processing unit 14 is detected when the OP unit 13 crosses the track, the CPU counts the number of mirrors. It detects the current seek position and reading position, and starts and stops the optical pickup operation.

The control of the spindle motor 22 is performed by the ATIP (Ab
solute Time In Pregroove) processing.
In a meandering groove called a wobble groove written on a recording medium, time information is recorded by FM modulation of +/- 1 KHz at a center frequency of 22.05 KHz in a radial direction. Modulated is a bi-phase modulated ATIP (Ab
solute Time In Pregroove).

When the focus and tracking are matched, the RF processing unit 14 extracts a wobble signal from a predetermined combination of the eight input signals. FM demodulation, AT
It is subjected to IP decoding, and extracted as a clock signal (FMCK) corresponding to the center frequency and time information (FMDT).

The FMDT includes a servo signal processing unit 15 (Servo Pr.
ocessor), which is stored in a predetermined register classified as an absolute time position of the medium, that is, an address and other additional information. In response, the CPU reads via the BUS.

In a read operation, a signal corresponding to a recording pit is extracted from a predetermined combination of eight signals by the RF processing unit 14, and is subjected to equalizer processing.
Fourteen Moduration) Signal processing unit 1 in signal format
7 is supplied. In the signal processing unit 17, CIRC (Cross Inte
(rleave Reed-Solomon Code) to perform decoding to obtain desired data.

Next, the write operation will be described. In the writing operation, first, the pickup is moved to the lead-in area to read the ATIP information. In addition, Special Information 2 (Special Imformation
Read out part 2).

FIG. 6 shows the outline of the frame structure of ATIP written in the lead-in area. The special information 1 is described in the frame of the frame number N in FIG. 6, and the special information 2 is described in the frame number (N + 10). Also, the frame number (N +
Normal time codes are described in frames 1) to (N + 9) and (N + 11) to (N + 19).

The start position of the lead-in area of the recording medium is written as time information in the special information area described for every 10 frames. In the special information 2 area described in the frame number (N + 10) read out here, the start position of the lead-in area is also described as time information in a predetermined format.

[0092] For example, one-half and one-half from the recording start point of the recording medium.
If the lead-in area starts from the position where one second has elapsed, the special information 2 area of the recording medium 25 contains 100 minutes to 2 minutes 11 of the total recording time.
A signal obtained by digitizing time information of 97 minutes and 49 seconds obtained by subtracting seconds is described. That is, the time information “97:49:00” is described as “1001 0111 0100 1001 0000 0000”.

The information written in the special information area corresponds to an identification code for identifying a recording medium. In the recording medium reproducing apparatus, a write strategy parameter corresponding to the identification code and other related parameters are stored in advance as a table. The write strategy is a correction parameter for correcting the laser pulse at the time of writing for each pit in the time direction and the level direction so that the pit size after writing satisfies the standard. The playback device is provided with a write strategy for each recording medium in advance. The recording signal according to the write strategy is set in detail, for example, as shown in FIG.

FIG. 7A shows an EFM signal. FIG. 7 (b) shows the actual R when writing the EFM signal of FIG. 7 (a).
The F signal is shown. Here, the recording signal according to the write strategy starts writing with a delay of aT, and the initial (bT) period of writing is described with an output that is ΔP larger than Pw, and thereafter, is determined to be described with the output Pw. Have been.

Next, an OPC (Optimum Power Calibration) operation for determining the optimum value of the laser output is performed. While the above-described write strategy is the detailed control of the laser for each write pit, the OPC operation is an operation for calculating the optimum value of the laser output throughout the entire write operation. By performing OPC, it is possible to obtain a pit write set value for realizing an ideal read target value.

The OPC is performed in the test area of the PCA. The test area is divided into 100 partitions, and this partition is specified by a relative time from the start time of the lead-in area. Each partition is
It is further divided into a maximum of 15 frames. This one
The laser output is adjusted by performing test writing immediately before writing using the partition.

Specifically, the laser output is changed stepwise from a predetermined value, and writing is performed on the recording medium at each step.
The laser output at this time is read out, the asymmetry in each stage is measured, and the set value of the laser output indicating the target asymmetry value is obtained by linear approximation from the set value near the target asymmetry.

Here, the asymmetry value is 3TPit / Land
And the center level of 11TPit / Land is defined, and is a value calculated by the following equation (1). FIG. 8 shows the demodulation levels of the pits used in calculating the asymmetry value.

Asymmetry value (%) = (3T center−11T center) / 11T amplitude (1) The target asymmetry value is an ideal value that minimizes the jitter value, and the asymmetry value is Included in the write strategy parameter as a value specific to the recording medium,
It is stored in advance corresponding to the start position information of the lead-in area of the recording medium. Here, the target asymmetry value is -5
%.

FIG. 9 shows the relationship between the laser output during writing and the asymmetry value after writing. As can be seen from FIG.
The laser output during writing and the asymmetry value after writing are in a proportional relationship. The laser diode used for the optical pickup of the CD-R generally has a large fluctuation in the laser output with respect to the operating environment temperature, and even if the laser output is set to a target asymmetry value at room temperature, as shown in FIG. The laser output greatly changes according to the environmental temperature. As a result, as can be seen from the graph showing the relationship between the asymmetry value and the recording jitter value shown in FIG. 10, the fluctuation of the asymmetry value greatly affects the deterioration of the recording jitter value.

Therefore, the OPC operation for determining the optimum value of the laser output needs to be performed immediately before the writing operation. After the optimum setting of the laser output is performed by the above operation, the OPC operation is prepared as a fixed value. Optimum writing is realized by setting each parameter. The measurement of the asymmetry value is taken in from the A / D converter and is performed in the signal processing unit.

In the count area of the PCA, when at least one sub-partition in each partition is used by OPC, the corresponding partition in the count area is painted out. Next time, when performing the OPC, the OPC operation is performed after seeking an unused subpartition in the used partition of the PCA.

Specifically, at the time of writing, after the compressed photographed image data prepared in the SRAM is subjected to CIRC or EFM encoding processing in the signal processor, the laser blinking / driving signal required for pit formation is formed. (DECEFMW),
The signal (write strategy) indicating the optimum value of the laser intensity is input to the laser driver of the OP unit.

At this time, FMDT obtained by decoding ATIP
Writing is performed at a predetermined position in timing along a file system based on an address in a frame unit obtained from a signal.

Normally, in the first writing, writing is started from a position skipping an area of about 20 Mbytes serving as a lead-in area in a later close session, but by using the optical recording medium according to the present invention, Second, since the closed session operation is unified for the second and subsequent times, writing is started from a position skipping an area of about 9.2 Mbytes as a lead-in area.

If the write-once recording medium is not to be additionally recorded anymore, or if it is to be reproduced on another reproducing apparatus such as a CD-ROM, the data is read by a reproducing apparatus compatible with a CD-ROM or the like. To enable this, it is necessary to perform a finalizing process (closed session operation) for writing the lead-in area and the lead-out area.

In the embodiment of the present invention, since a recording medium having a large write capacity and having been subjected to the first finalizing process (closed session) requiring a long time for the closed session operation is used, the second and subsequent closed session operations are performed. Just do it.

Hereinafter, the process of writing data on the optical recording medium according to the present invention will be specifically described with reference to FIGS.

For example, packet data of variable length in packet writing can be written up to 128 Kbytes in one packet, and the data capacity of one piece of image data after compression in a predetermined format becomes 800 Kbytes. Think about the case.

As shown in FIG. 11A, one packet includes one link (LINK) block, four block run-in (RI) blocks, variable-length packet data, and two block run-out (RO) blocks. ) Block. However, one block is 2 Kbytes.
As shown in FIG. 11B, one piece of image data having a variable capacity according to the image data is constituted by a set of one packet shown in FIG. 11A. When n images are continuously taken, one image data is written for n images as shown in FIG. 11C.
FIG. 11D shows a state in which the second closed session operation is performed on the n pieces of image data to write the lead-in area and the lead-out area. In the multi-session format, as shown in FIG. 11E, sessions formed by writing a lead-in area and a lead-out area are written one after another on a recording medium. In the optical recording medium according to the present invention, the first session has already been closed.

At this time, the writing unit of one image data is 6 packet data consisting of one block of link blocks, four blocks of run-in blocks, 128 Kbytes of packet data, and two blocks of run-out blocks. Each time, packet data consisting of one block of link blocks, four blocks of run-in blocks, 32 Kbytes of packet data, and two blocks of run-out blocks is written once, resulting in a total capacity of 898 Kbytes. When the data writing is completed, the usage status of the recording medium is written as temporary TOC information in the PMA provided further inside the lead-in area.

After n images have been captured in the same manner, the CD-ROM
Perform a finalizing process (closed session operation) to enable reproduction by a reproducing device that supports the above.

The first closed session operation performed on the optical recording medium according to the present invention will be described with reference to FIG.

When the execution of the closed session operation is instructed by a user's operation, the recording apparatus, in step S1, reads temporary table of contents information (hereinafter referred to as PMA) from the program management area (PMA) of the recording medium. , TOC: Table Of Contents). At this time, the recording device knows from the provisional TOC information that the recording medium has been subjected to the first closed session operation.

Next, in step S2, a regular TOC is created based on the information of the recorded area.

Next, in step S3, a lead-out area of about 4.6 Mbytes used in the second closed session operation is padded with zeros.

Subsequently, in step S4, a regular TOC is written in a lead-in area of about 9.2 Mbytes used in the second closed session operation, and when the writing is completed, the closed session operation is completed.

As described above, by using the optical recording medium according to the present invention, even the first closed session operation on the recording medium is executed from the second and subsequent closed session operations.

Therefore, when the optical recording medium according to the present invention is used, the first closed session operation which takes the longest time is not performed, so that accidents such as vibrations and shocks which may occur during the closed session operation can be avoided. It is possible to do.

Further, since the time required for the closed session operation is unified to the time required for the second closed session operation, it is possible to reduce the sense of discomfort that the user feels when the time required for the closed session operation is not constant.

The optical recording medium according to the present invention has the structure shown in FIG.
Is closed in advance. The closed first session may include the minimum necessary packet data, or may record other image information.

FIG. 13 shows a data structure when the minimum necessary packet data is included in the first session. FIG. 13A shows one packet including the minimum necessary packet data, and FIG. 13B shows a state where the closed session operation is performed including the minimum necessary packet data. ing. In FIG. 13B, a total of about 20 Mbytes of the lead-in area consumed in the first closed session operation and about 13.8 Mbytes of the lead-out area are consumed.
This indicates that 3.8 Mbytes of closed session data has been written.

Next, FIG. 14 shows a data structure when other image information is recorded in the first session. Here, MPEG (Moving Picture Exper
ts Group: Moving Picture Coding Experts' Meeting) 500KByte of MPEG moving picture data that has been compressed in accordance with the standard defined by it. 14 (a) to 14
As shown in (c), the writing unit of a series of moving image data at this time is composed of one block of link blocks, four blocks of run-in blocks, 128 Kbytes of packet data, and two blocks of run-out blocks. Since packet data is written three times, and packet data including a link block for one block, a run-in block for four blocks, a packet data of 116 Kbytes, and a run-out block for two blocks is written once, a total of 556 K bytes
It is the capacity of byte. This 556 Kbyte data is written and the first session is closed.

Next, a process for reproducing the recording medium 25 as the optical recording medium according to the present invention will be described with reference to FIG. When the recording medium in which the first session is closed is mounted, the digital still camera 1 automatically transfers still image data such as a sample image written in the first session or moving image data such as an advertisement. Reproduce.

The digital still camera 1 includes a recording medium 25.
When the reproduction is instructed, it is determined in step S10 whether or not the reproduction is the first reproduction for the loaded recording medium 25. If the playback is not the first playback for the loaded recording medium 25, the automatic playback process ends, and the process shifts to the normal playback process.

If it is the first reproduction, step S11
In, the digital still camera 1 reads the TOC information of the first session from the lead-in area.

Subsequently, in step S12, the image data written in the first session is JPEG (Joint Ph
It is determined whether or not the data is compressed in otographic Coding Exprets Group format.

If the data is compressed in the JPEG format, in step S13, the image is decompressed by JPEG, the image is displayed on the display for a predetermined time, and the automatic reproduction process is terminated. Transition.

If it is not the JPEG format, step S1
In step 4, it is determined whether the data is data compressed in the MPEG format. If the data has been compressed in the MPEG format, in step S15, after displaying this image on the display unit for a predetermined time, the automatic reproduction processing is terminated, and the processing shifts to normal reproduction processing.

Therefore, according to the optical recording apparatus of the present invention, it is possible to write the minimum data or additional information necessary for the closed session operation in the first session closed in advance. As a result, it is possible to avoid problems in the closed session operation due to vibration, impact, and the like, which are likely to occur during the first closed session operation that takes time.

It should be noted that the present invention is not limited to only the above-described embodiment, and it is needless to say that various changes can be made without departing from the spirit of the present invention.

[0132]

As described above in detail, the optical recording medium according to the present invention performs a closed session operation for making written data readable by another reproducing apparatus, and performs a closed session operation for each data set. Optical recording in which the recording area is divided and recorded, and the data amount of the closed session data written by the first closed session operation is larger than the data amount of the closed session data written by the second and subsequent closed session operations. A medium on which data for the first closed session is recorded.

Here, in the area where the first closed session operation has been performed, only the minimum data necessary for the closed session operation is recorded, and still image information and / or moving image information are recorded in advance. It is mentioned. Further, it is a write-once and / or rewritable recording medium.

Therefore, according to the optical recording medium of the present invention, the user performs only the second and subsequent closed session operations that have a small writing capacity and do not take much time, thereby reducing operational discomfort.

Further, according to the optical recording medium of the present invention,
It is possible to avoid problems of the closed session operation due to vibration, impact, and the like, which are likely to occur during the time-consuming first closed session operation.

Further, according to the optical recording medium of the present invention,
Various additional information can be provided to the user by performing a closed session operation by previously writing still image information and moving image information such as a product advertisement and a sample image in an area where the first closed session operation is to be performed.

[Brief description of the drawings]

FIG. 1 is a diagram showing a management unit (hereinafter, referred to as a volume) structure of a removable recording medium that accommodates files and the like in a UDF-compliant file system.

FIG. 2 is a diagram schematically illustrating a file seek process in a UDF-compliant file system.

FIG. 3 is a block diagram showing a configuration example of a digital still camera employing an optical recording medium according to the present invention as a recording medium.

FIG. 4 is a cross-sectional view showing a cut surface when the optical recording medium according to the present invention is cut perpendicularly to the medium surface.

FIG. 5 is a cross-sectional view showing a cut surface when the optical recording medium according to the present invention is cut perpendicular to the medium surface.

FIG. 6 is a schematic diagram showing an outline of a frame structure of ATIP information written in a lead-in area of the optical recording medium according to the present invention.

7A is a diagram showing the intensity of an EFM signal that changes with time, and FIG. 7B is a diagram showing the EF of FIG. 7A.
FIG. 3 is a diagram illustrating the actual RF signal strength when an M signal is written.

FIG. 8 is a diagram showing demodulation levels of pits used when a digital still camera employing an optical recording medium according to the present invention as a recording medium calculates an asymmetry value for each recording medium.

FIG. 9 is a relationship diagram showing a relationship between a laser output when writing data to a recording medium and an asymmetry value after writing in a digital still camera employing the optical recording medium according to the present invention as a recording medium.

FIG. 10 is a relationship diagram showing a relationship between an asymmetry value at the time of writing and a recording jitter value calculated by a digital still camera employing the optical recording medium according to the present invention as a recording medium.

FIG. 11 is a data configuration diagram showing a data configuration of the optical recording apparatus according to the present invention.

FIG. 12 is a flowchart illustrating an initial closed session operation performed on the optical recording medium according to the present invention.

FIG. 13 is a data configuration diagram showing a data configuration when a minimum necessary packet data is included in the first session of the optical recording medium according to the present invention.

FIG. 14 is a data configuration diagram showing a data configuration when other image information is recorded in the first session of the optical recording medium according to the present invention.

FIG. 15 is a flowchart illustrating a process when reproducing an optical recording medium according to the present invention.

FIG. 16 is a flowchart illustrating a finalizing process (closed session operation) performed in a conventional recording apparatus.

[Explanation of symbols]

Reference Signs List 1 digital still camera, 10 image pickup device, 11 image signal operation processing unit, 12 display unit, 13 OP unit, 14
RF processing unit, 15 servo signal processing unit, 16 analog filter processing unit, 17 signal processing unit, 18 spindle driver, 19 thread driver, 20 tracking driver, 21 focus driver, 22 spindle motor, 23 thread motor, 24 control unit, 25
Recording medium, 30 lens unit, 31 charge-coupled device, 32
S / H circuit, 33 A / D conversion circuit

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5D044 BC05 CC04 DE23 DE49 DE54 DE57 EF05 GK12 5D090 AA01 BB03 CC01 CC04 CC14 DD03 DD05 FF49 GG29 GG32 GG33 GG36 5D110 AA16 AA27 AA29 DA01 DA11 DB03 DC15 DE04

Claims (4)

[Claims] 1. A closed session operation for making written data readable by another playback device is performed, a recording area is divided and recorded for each set of data, and written by an initial closed session operation. An optical recording medium in which the data amount of the closed session data to be written is larger than the data amount of the closed session data to be written by the second and subsequent closed session operations, wherein the first closed session data is recorded. An optical recording medium characterized by the above-mentioned. 2. The optical recording medium according to claim 1, wherein only the minimum data required for the closed session operation is recorded in the area where the first closed session operation has been performed. 3. The optical recording medium according to claim 1, wherein still image information and / or moving image information are recorded in an area where the first closed session operation has been performed. 4. The optical recording medium according to claim 1, wherein the optical recording medium is a write-once type and / or a rewritable type.