JPH04188467A - Optical disk - Google Patents

Abstract

PURPOSE:To make it possible to regenerate program data which are recorded up to now at random even at a stage wherein the entire program is not finished in one disk by recording partitioning data in the region of a table of contents beforehand before the partitioning data for partitioning a program region at a time unit are written as the table-of-content data. CONSTITUTION:An optical disk 1 has a read-in region 2, a program region 3 and a read-out region 4. In the read-in region 2, TOC data as the data of a table of contents are recorded in the read-in region 2. The TOC data are partitioning data for partitioning the program region 3 at the specified time unit. The program data are recorded in the program region 3. In this way, even if the program is recorded to the halfway of the program region, the random regeneration can be performed, and the individual identification of the optical disks can be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] This invention relates to a writable optical disc, and in particular, prior to writing data to a program area, segmentation information for segmenting the program area in units of time is provided. The present invention relates to an optical disc in which the table of contents is recorded in the table of contents area.

[Prior Art] Conventionally, optical discs on which data can be written include those in which recording bits are formed by melting a metal film or color change in a pigment film, and magneto-optical discs that utilize magneto-optical effects. Are known. With these optical discs, is it desirable to be able to randomly play back the written program while the program is partially recorded in the program area?To do this, it is necessary to write a lead-in before the program area, similar to CDs that are exclusively used for continuous production. Each track (song number) in the area
TOC (Table of Con
It is necessary to record table of contents information such as "tents') information.

[Problems to be Solved by the Invention] However, in conventional writable optical discs, the contents of the table of contents information are not determined until all program information has been recorded. , I can only write table of contents information. For this reason, there is a problem in that when a program is recorded only partway through the program area, random playback is only possible.

Furthermore, in this type of optical disc, the volume characteristics, frequency characteristics, etc. during playback may change depending on the recording state when a program is written to each optical disc. Therefore, during random playback, it is necessary to set optimal playback characteristics for each individual disc.

However, in the past, it was only possible to identify individual optical discs, so it was not possible to associate optical discs with playback characteristics. For this reason, it is necessary to reset the optimal playback characteristics each time an optical disc is set, which makes the setting operation complicated, and there is also the problem that it is not possible to obtain the desired sound quality immediately from the start of playback.

This invention was made to solve these conventional problems, and it is possible to perform random playback even when a program is recorded only halfway in the program area, and moreover, it is possible to perform random playback even when a program is recorded only halfway in the program area. The objective is to provide an optical disc that can be identified.

[Means for Solving the Problems] The optical disc of the present invention has a program area for writing data, and segmentation information or table of contents information for segmenting this program area in units of time, which is recorded in advance before data is written. In an optical disc having a table of contents area,
The classification information is characterized in that it differs slightly for each individual optical disc.

[Function] According to the present invention, the classification information for dividing the program area in units of time is recorded in advance in the table of contents area as table of contents information before data is written, so that when recording program information on an optical disc, Even when all programs are not completed on one disc, by referring to the table of contents information, the program information recorded up to that point can be randomly reproduced.

Furthermore, if the program area is uniformly divided into the same time units, the table of contents information of each optical disc will be the same information, making it impossible to identify individual optical discs.
In this invention, since the classification information is slightly different for each optical disc, it is possible to identify each optical disc.

Therefore, for example, when playing a program in which playback characteristics and the like are set in advance, it is possible to easily match the playback characteristics to the optical disc, and the operation during program playback can be simplified.

Further, for example, if there is an abnormal tracking location on the optical disc, subsequent tracking control can be facilitated by correlating the information of that location with the optical disc.

[Embodiments] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

In addition, here, we will refer to a CDS created by recording CD format information on a CD standard write-once optical disc.
An embodiment in which the present invention is applied to a CD-ROM, CD-1, CDV, etc. will be described.

FIG. 2 is an external perspective view showing the CD of this embodiment.

That is, the disk 1 includes In on the surface of a transparent disk substrate made of polycarbonate or acrylic, for example.

It is made of a thin alloy film containing Bi, Sn, TeC, etc. and has an outer diameter of 120 mm, an inner diameter of 15 mm, and a thickness of 1.2 mm. This optical disc 1 includes a lead-in area 2 at an inner diameter position of about 46 mm to 50+++ m, a program area 3 at a subsequent position of about 50 mm to 116 n++n diameter, and a lead-out area with a width of 0.5 mm or more after the program is finished. It is equipped with 4.

In the lead-in area 2, TOC information is recorded in advance as table of contents information. This TOC information is segmentation information for segmenting the program area 3 in predetermined time units.

Program data is recorded in the program area 3. Further, in the lead-out area 4, a signal indicating the end of the program is recorded.

The recording information recorded on this optical disc l is EFM
(Eight to Fourteen Modula
tion) consists of a frame consisting of 588 modulated channel bits. The structure of one frame in the program area 3 is shown in FIG. Program area 3 consists of 1 frame, 24 channel bit synchronization signal, 1 symbol (8 channel hits) subcode, 12
Symbol information bits, 4 symbol check bits,
It is constructed by arranging 12 symbols of information bits and 4 symbols of check bits in this order. Among these, the subcodes are collected for 98 frames, P, Q, R, S, T
, U, V.

Eight types of 98-bit subcode frames of W are constructed.

On the other hand, in the lead-in area 2 as well, a Q channel subcode frame is configured by similar subcodes. Of these, 72 bits of the data part are preset with TOC.
Information is recorded.

FIG. 1(a) and FIG. 1(b) each show TOC information written on different optical disks.

That is, the TOC information includes an address section 11, a track number section 12, a relative time recording section 13 in the TOC, and a zero recording section 14.
and a start time recording section 15 for each track.The recording sections 13 and 1.5 further include minute display sections 13a and 15a, second display sections 13b and 15b, and frame display sections 13c and 15, respectively.
It is composed of c.

In the address section 11, 8-bit data "00" which is a recording track number of TOC information is recorded.

Further, the program area 3 is divided into 60 tracks, for example, in time units of about 1 minute. Track number section 12
In the start time recording section 15 of each track, the number and start time of each track in the program area 3 thus divided are recorded in association with each other. Furthermore, the start track number, last track number, and total time of the program area 3 are recorded in the subcode frames indicated by track numbers AO, AI, and A2, respectively. Note that this information is recorded redundantly over three subframes to improve recording security.

The relative time recording section 13 in the TOC records the start time in the 0 track of each subcode frame of the TOC information.

By the way, among the start times of each track of the TOC information, the frames recorded in the frame display section 15c have different values for each track, as shown in FIG.
As shown in b), the value is different for each disc. Therefore, each optical disc 1 can be identified by the pattern of the frame display section 15a.

Note that the time interval between each subcode frame is approximately 13.3
ms, and the value of the starting frame is 1 from 00 to 09.
Assuming that it can be between 0 frames, the difference in length between each track is at most 0.133 sec. Therefore, for a track of about 1 minute, the track length does not change significantly.

Furthermore, since 10 types of start frame numbers can be assigned to one track, it is possible to obtain io'' types of patterns as TOC information for an optical disc having 60 tracks.

Even if a CD player can only recognize the first or partial five tracks of TOC information, it is possible to obtain 105 different patterns. Therefore, the probability that different optical discs have the same TOC information is extremely low.

Such TOC information is written into the lead-in area 2 in an initialization process performed prior to recording program information or in a blanking process during disk manufacturing.

When writing music information as program information to an optical disc l on which TOC information has been written, first write the optical disc l.
After setting the optical disc 1 in the recording device, the TOC information is read from the optical disc 1 and stored in a memory (not shown). When writing the first song, the optical head moves to the program area 3.
When the first position of the track is reached, the subcode generator starts counting the relative time and absolute time of each track, and generates a subcode with the track number set to 01. Then, using this subcode and program information, recording in the CD format described above is performed at a constant linear velocity.

When the writing of information for the first song is completed, the input information becomes 0, but recording of subcodes continues until there are no unrecorded portions on that track.

When recording the next song, the optical disc 1 is set in the recording device, the TOC information is read, and the TOC information is stored in a memory (not shown). Detect the boundary of the section and read the immediately preceding track number and absolute time. Then, based on the read track number and absolute time, the subcode generator is preset, the track number and each time count are started in the same manner as above, and information is written.

When recording has been completed for all tracks in the program area 3, or when no further information is to be recorded, information is written for the generation of the lead-out area 4.

On the other hand, when reproducing the recorded optical disc 1, the optical disc 1 is set in a reproducing device. As a result, TOC information is read from the optical disc I and stored in the TOC memory. Random playback can be performed by inputting the track number using, for example, a numeric keypad. That is, since the correspondence between the song number and the track number has been determined through a series of information writing operations, based on this, the starting track number of the song number desired to be reproduced is input as data.

When a track number is input, the start position of that track is determined from the TOC information, and based on that start position, a search is performed using the subcode frame of the Q channel, and random playback is performed similar to a normal CD player. Is it possible to do this?

At this time, for example, as shown in FIG. 4, the center frequency fL in each of the low, middle, and high bands.

f,,f,,Level LEVL,LEV,.

LEV) l and Q values QL, Q, , Q, low-cut and high-cut frequencies fLc+fHc, and slope S
By setting LL and SLH to optimal values and storing these playback parameters in memory, it is possible to read out these parameters and perform program playback at the next playback.

That is, when an instruction to store parameters is given, as shown in FIG. The numbers are associated with each other and stored in a non-volatile memory or the like. Furthermore, as shown in FIG. 6, the parameters set above are also stored in association with the same individual identification number.

Next, when playing back the same optical disc, by specifying program play, the individual identification number of that optical disc is determined from the TOC information, and the playback parameters corresponding to the determined individual identification number are read out. Then, program playback will be performed.

In this way, according to the optical disc of this embodiment, by randomly shifting the start position of each track that divides the program area between 0 and IO frames, it is possible to make the TOC information different for each optical disc. This makes it possible to identify each optical disc.

Therefore, by storing the optimum playback characteristics for each optical disc, it is possible to set the optimum playback characteristics with a simple operation.

Furthermore, for example, if there is an abnormal tracking spot due to a scratch or the like on the optical disc l, tracking control can be facilitated by storing information indicating the position in association with the individual identification number of the optical disc 1. is also possible.

Furthermore, in addition to these methods, the present invention can of course also be applied to disc discrimination when the playback order of favorite songs is preset in advance (so-called program selection function) as a simpler usage method.

It goes without saying that the present invention is applicable not only to the above-mentioned CD but also to other types of optical discs such as video discs.

[Effects of the Invention] As described above, according to the present invention, 1.
Even when all programs are not completed on one disc, by referring to the table of contents information, the program information recorded up to that point can be randomly reproduced.

Further, according to the present invention, since the classification information is slightly different for each optical disc, it is possible to identify each optical disc based on the classification information.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing TOCt)I information recorded in the lead-in area of an optical disc according to an embodiment of the present invention.
Figures (a) and (b) are schematic diagrams showing TOC information written on different optical discs, Figure 2 is an external perspective view of the same optical disc, and Figure 3 is a schematic diagram showing the information written on the same optical disc. FIG. 4 is a schematic diagram showing the frame structure; FIG. 4 is a graph diagram showing an example of the playback characteristics of the optical disc; FIG. 5 is a schematic diagram showing the correspondence information between the start frame of each track of the optical disc and the individual identification number; The figure is a schematic diagram showing correspondence information between the playback characteristics and individual identification numbers of the same optical disc. ■...Optical disc, 2...Lead-in area, 3...
・Program area, 4...Leadout area, 11.
...Address section, 12...Track number section, 13...
- Relative time recording section in TOC, 14... zero recording section,
15... Start time recording section of each track.

Claims (1)

[Claims] (1) In an optical disc comprising a program area for writing data and a table of contents area in which classification information for dividing the program area in units of time is recorded in advance as table of contents information before writing the data, the above-mentioned An optical disc characterized in that classification information is slightly different for each optical disc.