JP3257579B2 - Optical disk and its check device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk for preventing unauthorized copying on a CD-ROM or the like on which information such as a TV game is recorded, and a check device therefor.

[0002]

2. Description of the Related Art When music, images, characters, data, and the like are represented as digital information signals, the information is copied (copied) when compared with the case where they are represented as analog signals. There is no deterioration. For this reason, it is currently a serious problem in terms of copyright, and it is required to prohibit or restrict the copying of digital information signals as they are.

[0003] For example, CD-ROMs and the like
60 "and the like. When copy protection is performed in accordance with this standard, a copy protection code must be recorded on a disc in advance. And if it has this code, it is a legitimate disk,
If there is no code, it is determined that the disk is an illegal copy disk, and measures such as stopping the reproduction are taken. It is considered that CD-ROMs currently being commercialized and those to be commercialized in the future will conform to this standard.

[0004] However, in such a copy prevention method, if a copy machine that copies the entire recording data of the disk is used, it is possible to easily manufacture a copy disk that can be accepted as a regular disk. For this reason, discs with weak copy protection are circulated, which leads to illegal copying.

[0005] Therefore, a unique standard different from the above-mentioned disc standard has been created, and a standard CD such as “ISO9660” has been developed.
-A method of applying copy protection so that it cannot be read by software that reads ROM can be considered. However, even if such a method is used, data is read from a disk in units of physical frames or blocks, and a CD-W
If a copying machine that copies to O (write-once disk) is used, any disk will be copied.

Meanwhile, as copy protection measures up to now, a copy code is written in a VTR, a DAT or the like in a hardware manner or in a software (logical) manner like an SCMS (serial copy management system). is there. As a copy protection measure for writing a copy code in hardware, there is a method of using a pit (pseudo pit) smaller than usual as a copy code (for example, Japanese Patent Laid-Open No. 61-178732). As a copy protection measure for writing a copy code by software, there is a method of writing a copy protection code in conformity with a specific format (for example, JP-A-63-292458).
issue).

[0007]

However, in the case of a copy protection apparatus in which copy codes are written in software, a CD-ROM in which copy codes are written in software cannot be read by software for reading ordinary CD-ROMs. However, if a copying machine that reads data in lower frame or block units and copies the data to a CD-WO or the like is used, the effect of copy protection is lost and any disc is copied. In particular, CD-ROM
Write a copy code in the main data of a general-purpose OS
The entire disc can be copied relatively easily from above, which is a copyright problem. At least, copy protection measures must be taken so that copying is not possible with dedicated copy software on a general-purpose OS or a host computer.

The optical disk of the present invention is a disk in which a copy protection code is recorded in a buffer area which is an undefined area constituting a data area. The optical disk check apparatus of the present invention reproduces an optical disk to be inspected. The copy protection code is recorded in the buffer area, whereby the present invention determines that the copy protection code is present when the copy protection code is present. The purpose is to judge as.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides an optical disk having the following constitutions (1) and (2) and a check device therefor.

(1) A copy protection code for recording data in accordance with the IEC 908 standard, which has at least a buffer area which is an undefined area and a data area having a lead-in area, and wherein the buffer area includes time information, An optical disc, wherein the time information is recorded, and the time information is temporally discontinuous from the time information of data recorded in the lead-in area.

(2) An optical disc checking apparatus for discriminating an optical disc according to (1), wherein the reading means reads the optical disc to be inspected and reads time information of a buffer area and a lead-in area; Discriminating means for discriminating whether or not the time information of the two regions is temporally continuous, and when the time information is temporally discontinuous, the optical disc to be inspected is determined to be a regular optical disc An optical disk checking device, characterized in that:

[0012]

The disc to be inspected 1 of the above-described embodiment is set in the check device A and reproduced, and it is determined whether or not a copy protection code can be obtained.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an optical disk and a check device thereof according to the present invention will be described with reference to FIGS. FIG. 1 is a diagram for explaining the contents of subcode data constituting a digital signal sequence obtained by reproducing the optical disc of the present invention, FIG. 2 is a diagram for explaining the structure of Q channel data in a lead-in area, FIG. 3 is a diagram for explaining the scan start time of the lead-in area, FIG. 4 is a block diagram of the optical disk checking device of the present invention, and FIG. 5 is a detection operation flowchart of the optical disk checking device of the present invention.

As will be described later, the optical disk of the present invention has
A specific channel of a subcode recording portion of an optical disk such as a CD-DA (digital audio CD) having an outer diameter of 120 mm or 80 mm, a CD-ROM (read-only data CD mainly for numbers and characters, etc.). IEC908
An object of the present invention is to provide a disk which satisfies the standard (the so-called Red Book Standard, hereinafter referred to as Red Book Standard) and in which a copy protection code described below is written in addition thereto. Incidentally, the JIS X6281 standard is called the Yellow Book standard, and the standard uses part of the Red Book standard mutatis mutandis.

That is, as will be described later, the optical disk of the present invention is recorded in conformity with the IEC908 standard and has at least a data area having a buffer area and a lead-in area which are undefined areas. An optical disc on which a copy protection code is recorded.

Incidentally, the Red Book standard is:
A CD (Compact Disc) standard developed by both Sony and Philips (announced in 1981). Here, the specifications regarding the dimensions of the disk (outer diameter: 120 mm, hole diameter: 15 mm), recording format, data area, error correction code CIRC, subcode area for access to program designation and cueing are specified.

The optical disk checking apparatus of the present invention, when handling the optical disk having a copy protection code recorded in a buffer area as a regular disk,
The disc to be checked is reproduced to determine whether or not there is a copy protection code, so that the disc can be reliably identified as a legitimate disc based on the copy protection code.

The optical disk of the present invention generally comprises a non-data area formed on the outer circumference of the center hole and a data area formed from the outer circumference of the non-data area to the outermost circumference of the disk (both are not shown). The data area is an area in which a large amount of various data such as TOC on the innermost side is recorded as a large number of pit rows in a spiral or concentric manner around the center hole. The non-data area is an area where no data is recorded. As will be described later, the data area includes a buffer area, a lead-in area, and a data area (program area) in order from the inner periphery.

As shown in FIG. 1, a series of reproduced digital signal sequences obtained by reproducing such a disk are sequentially continuous in units of a frame d composed of a frame synchronization signal a, a subcode b, and main data c. It is. The main data c is digital audio P
Stores CM-level data and text-level data mainly for reading, mainly for numbers and characters.

As shown in FIG. 1, for the subcode b, eight channels of P, Q, R to W are allocated to an area of one symbol, eight bits b1 to b8, immediately after the frame synchronization signal a.
The contents of each channel are completed in 98 frames (1 symbol = 98 frames = 1 section). The first two frames (byte numbers 0 and 1) of each channel of the subcode b constitute subcode synchronization signals 1 and 2 common to each channel, and have the following pattern after EFM modulation.

Subcode synchronization signal 1 (S0 pattern): “00100
000000001 ”Subcode synchronization signal 2 (S1 pattern):“ 00000 ”
0000001010 "

The P channel code stored in the P channel is, for example, the first program area (main data) of a song.
Is "1" for the first few seconds of the program area, and is "0" for the rest (P code).

As shown in FIG. 2, the Q channel code stored in the Q channel is control (byte numbers 2 to 5), Q
Mode (4 bits, byte numbers 6 to 9), Q data (7
2 bits, byte numbers 10 to 81), CRC (CRC
C, 16 bits, and byte numbers 82 to 97).

The control signal stored in the control (byte numbers 2 to 5) is, for example, a signal that defines the number of audio signal transmission channels and the presence or absence of pre-emphasis. The address signals stored in the Q mode (byte numbers 6 to 9) are defined in three modes (modes 1 to 3) as described later.

The Q data (byte numbers 10 to 81) include:
It is specified that the following signals (1) to (5) are stored, and is composed of a 4-bit 2-digit BCD code. (1) Number of tracks: number of tracks in the playback disk (8 bits, byte numbers 10 to 17) (2) Index: Number of tracks being played (track number) (8 bits, byte numbers 18 to 25) (3) Relative time: playback time from the beginning of each track (minutes,
Second, frame (1/75 second) display, minute (8 bit, byte number 26-33), second (8 bit, byte number 34-4)
1), frame (8 bits, byte numbers 42 to 49) (4) "0": 8 bits, byte numbers 50 to 57 (5) Cumulative time (absolute time): Cumulative reproduction time from the beginning of the first track ( Minute, second, frame display), minute (8 bits, byte numbers 58 to 65), second (8 bits, byte numbers 66 to 73), frame (8 bits, byte number 74)
~ 81)

Although not described in detail here, the reproduction of the Q channel code allows the optical disk player to display the track number (song number) and time on the display, and at the same time,
Access to any truck is possible.

That is, the position of the pickup is confirmed by the reproduced Q channel code, the number of tracks to be moved to the target track (target music) is calculated (calculated from the total reproduction time difference and the linear velocity), and the pickup feed servo is forcibly fed to perform an access operation. , The pickup position is accurately grasped by the reproduced Q channel code, and the next access operation is performed.
All of these controls are performed by a microcomputer (a control circuit 2 described later), and the access operation ends when the pickup is positioned at the target track (none of them is shown).

Now, the Q mode (byte numbers 6 to 6)
As for the 4-bit address signal stored in 9), three modes are specified as follows. Mode 1 (“0001”): Track number, time code, etc. Mode 2 (“0010”): Disc catalog number Mode 3 (“0011”): Country, copyright holder code, etc. (Mode 3 is originally digital This mode defines the mode of audio. Here, a case is shown in which, when a CD-ROM is used, a code having the above contents is stored in this mode.) The appearance frequency is as follows. Stipulated. Mode 1 appearance frequency: 9 or more in 10 continuous sections Mode 2 appearance frequency: 1 or more in 100 continuous sections Mode 3 appearance frequency: 1 or more in 100 continuous sections

As described above, the lead-in area is located on the innermost side of the data area of the optical disk, and the Q data of the subcode Q channel in that area is the arrangement information of various data of the entire optical disk. TOC data is stored. That is, the Q data (TO
C) The table is the array shown in FIG. From the top, track number (TNO), pointer, relative time (minute (MIN), second (SEC), frame (FRA)
C)), “0”, cumulative time (minutes (P-MIN), seconds (P
-SEC), frame (P-FRAC)).

As shown in FIG. 3, the arrangement of the lead-in area of the optical disk is a data area having a diameter of 44 mm or more, and the start position of the lead-in area is d <45.0.
mm to 46.0 mm, the end position of the lead-in area is d> 5
0.0 mm + 0 mm and 50.0 mm-0.4 mm (d: diameter). Incidentally, a diameter of 44 mm or less is a non-data area, in which a lot number of the optical disk or the like is entered by a stamp, a bar code, a mosaic, or the like. The center hole exists in the non-data area.

By the way, from the beginning of the data area to the beginning of the lead-in area, that is, d <44.0 mm + 1
mm to 46.0 mm is defined as a buffer area, which is a data area, not a lead-in area, and the content of data is not defined.

(Embodiment 1) Corresponding to the first aspect of the present invention Therefore, the inventor actively uses the buffer area which is the undefined area from the beginning of the data area to the beginning of the lead-in area. Then, the copy protection code is recorded here, and the disc on which the copy protection code is recorded is handled as a regular optical disc.

Next, a method of determining the copy protection code will be described. Basically, any code (data) can be stored in the buffer area. The reason is that it is sufficiently possible to read the sub-code b with the microprocessor (control circuit 2 described later) of the optical disk player. This can be realized by reading the code and determining whether the reference code matches the read code.

However, the optical disc player sets the buffer area of the optical disc in which the copy protection code is recorded in a normal lead-in area ("true lead-in" shown in FIG. 3).
If this TOC data is read as erroneous as the normal TOC data, it is inconvenient to perform the reproduction process because erroneous reproduction is performed. For this reason, as the copy protection code to be stored in the buffer area, inconsistent TOC data is recorded as short data as possible (i.e., in order to prevent reproduction of data as incorrectly read TOC data is regarded as normal data). There is a need to). In this way, the reproduction of the normal lead-in area starts following the tracing of the buffer area, and the normal TOC data can be read here, so that there is no further problem.

The copy protection code recorded in the buffer area has almost the same subcode format as that of the normal lead-in area, and the value of the subcode in the normal lead-in area is determined by the standard. There is also a method of writing, as the copy protection code, data that is read and discarded by the player instead of the unique information.
For example, (1) When the pointer of the Q data (TOC) table in the lead-in area is “A0”, the accumulated time (minutes) PM
Write “00” in IN. (That is, although the pointer is not the head, the cumulative operation (minute) is “00”, so the reproduction operation based on the cumulative time (minute) cannot be performed.) (2) A value other than “0” in the zero area Write down. (That is,
Since there is no “0” in the area where the “0” data is to be stored, the reproduction operation cannot be performed based on the data in the zero area.)

Further, the Q data (TO
C) The same data as the subcode of the table can be recorded in the buffer area as a copy protection code.
That is, as shown in FIG. 3, the sub-code (so-called,
False TOC) also increases as the playback time of MIN, SEC, and FRAC increases, but here, the false T
Since the reproduction of the normal lead-in area starts following the buffer area tracing, the values of MIN, SEC, and FRAC return to the initial values (arbitrary in the standard) and return to the values in the normal lead-in area. Are sequentially increased. The optical disc player may read the intermittent phenomenon of the time information and use it as a copy protection code.

(Embodiment 2) In accordance with the second aspect of the present invention, an optical disk checking apparatus according to the present invention generally defines a copy protection code recorded in a buffer area constituting the above-mentioned data area. An optical disk from which a code can be read is determined as a regular disk.

That is, this optical disk checking apparatus
It has the following configuration. A pickup 7 for reading the optical disk 1 to be inspected and reading a copy protection code;
An optical disk checking apparatus A, comprising: a control circuit 2 for determining the presence or absence of a read copy protection code; and determining that the optical disk is a regular optical disk based on the read copy protection code. The optical disk checking device A may have a configuration of an extremely general optical disk player. However, the pickup needs to be able to move to the inner periphery (to the buffer region) more than the innermost periphery of the normal lead-in area.

More specifically, an optical disk checking device A
As shown in FIG. 4, the control circuit 2, the servo processing circuit 3, the drivers 4 and 5, the spindle motor 6, the pickup 7, the RF amplifier 8, the RF signal processing circuit 9, the decoder 9
A. 1 is a disk to be inspected.

The detection operation flowchart shown in FIG. 5 is for judging that a disc is a legitimate or illegal copy disc when the disc has a write method in which the time data is reduced.

That is, the control circuit 2 constituting the optical disk check device A confirms that the disk 1 to be inspected has been set on a turntable (not shown), and when the user selects a check operation (play operation), the control circuit 2 In response, the control circuit 2 sends a disk rotation start control signal to the servo processing circuit 3 (100). Upon receiving the disk rotation start control signal, the servo processing circuit 3 sends a motor drive signal for rotating the spindle motor 6 in the rotation stopped state to the driver 4 in response to the signal. The driver 4 amplifies the motor drive signal and outputs the motor drive signal to the spindle motor 6.
To supply. At about the same time, the servo processing circuit 3 sends to the driver 5 a transfer signal for first transferring the pickup 7 to the buffer area under the control of the control circuit 2.

Thus, the spindle motor 6 rotates the disk 1 to be inspected set on the turntable CLV, and the pickup 7 is transferred to the buffer area to enable the trace reproduction (110). The control circuit 2 temporarily stores the TOC data (of the buffer area or the normal lead-in area) supplied from the pickup 7 via the RF amplifier 8 and the RF signal processing circuit 9 in the built-in memory (the normal read is performed in the buffer area). TOC of in area
It is assumed that the same TOC data as the data is stored).

As a result, the control circuit 2 controls the RF amplifier 8, R
The subcode b of the TOC data sequentially supplied from the pickup 7 via the F signal processing circuit 9 is decoded.
The control circuit 2 controls the sub-code b supplied from the decoder 9A.
Of the Q channel control data (Q code), and the 4-bit Q code is, for example, "00XX".
In the case of (X may be either “0” or “1”), the disc 1 to be inspected is determined to be a CD-DA. Then, this can be reproduced (120, 130).

On the other hand, the control circuit 2 decodes the content of the control data (Q code) of the Q channel of the subcode b supplied from the decoder 9A, and when the 4-bit Q code is, for example, "01XX". When the control circuit 2 determines that the disk 1 to be inspected is a CD-ROM, the control circuit 2 continuously reproduces the sub-code b of the CD-ROM.

Subsequently, the control circuit 2 decodes the contents of the subcode b of the TOC data sequentially supplied from the pickup 7, and outputs the time data of the Q data of the Q channel supplied from the decoder 9A (for example, the cumulative time ( The control circuit 2 counts up the built-in counter on the basis of the absolute time). Data (eg, cumulative time (absolute time)) content is continuously played back). When shifting from the buffer area to the lead-in area,
Once the count value of the counter built in the control circuit 2 once decreases (for example, becomes all "0"), it is determined that the disk is a legitimate disk (140 to 160).

On the other hand, if the count value of the counter built in the control circuit 2 does not decrease and continues to count up, the TOC
It is determined whether or not all of the data has been captured. If not, the time data of the Q data is captured again (170 → 140). When it is determined that the import of the TOC data has been completed, it is determined that the disk is an illegal copy disk,
Eject an illegally copied disk out of the device (170-19)
0).

As described above, when the same TOC data is recorded in both the buffer area and the lead-in area as shown in FIG. The time data of the TOC data is counted up from the initial value, and it is determined that the time data is disconnected.
It can be checked whether it is OM or a regular CD-ROM.

[0048]

The optical disk according to the present invention is a disk in which a copy protection code is recorded in a buffer area which is an undefined area.
By reproducing the inspected optical disk and determining the presence or absence of the above-described copy protection code, it is determined that the disk is a legitimate disk based on the copy protection code, while a disk without such a code is determined as an unauthorized copy disk. Can be. Further, if an unauthorized copy disk obtained by illegally copying the authorized disk of the present invention is set in a normal CD-ROM drive and is to be played back, the authorized disk is provided with a measure for preventing copy on the main data. Because it is not copied, it can be accurately copied to a CD write-once disc or the like, and no error occurs. A large number of duplicated disks can be manufactured using the master as a master. However, even if the main data in the data area after the lead-in area (TOC area) can be duplicated, the copy protection code in the buffer area cannot be duplicated. When a check device (reproducer) with a detection function is used, the copy protection code in the buffer area is not detected and reproduction cannot be performed. Therefore, it is possible to reliably protect the copyright of a regular disc. Furthermore, since a normal CD-ROM drive does not trace to the buffer area where the copy protection code of the present invention is recorded, it is difficult to notice that the copy protection code is recorded in this area. Even if the buffer area is traced, if the data is inconsistent with the TOC, the pickup is skipped, the seek is performed to the normal lead-in area, and the TOC in that area is read to perform the reproducing operation. Since it is not noticed that the copy protection code is recorded, it is possible to prevent the copy protection code located here from being further copied. Furthermore, the check device (reproducer) of the present invention normally provides a copy protection code (for example, TO
Since C) is read, it can be detected in a short time whether or not the disc is a legitimate disc. Furthermore, because the code is not written in the main data, it is difficult to analyze the copy guard, and because the logical code is written, the burden of remodeling the disc manufacturing equipment is less than the method of writing in hardware. And there is no hardware burden because only the software of the playback device needs to be modified. Therefore, it is advantageous in terms of cost and reliability, and all of the embodiments conform to the IEC908 standard, so that the disc of the present invention can be easily put on the current distribution network when selling the disc.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining the contents of subcode data constituting a digital signal sequence obtained by reproducing an optical disk of the present invention.

FIG. 2 is a diagram illustrating a configuration of Q channel data in a lead-in area.

FIG. 3 is a diagram for explaining a scan start time of a lead-in area.

FIG. 4 is a block diagram of an optical disk checking device according to the present invention.

FIG. 5 is a flowchart of a detection operation of the optical disk checking device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Inspection optical disk 2 Control circuit (determination means) 7 Pickup (reading means) A Optical disk check device b Subcode data c Main data

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Claims (2)

(57) [Claims] 1. Data is recorded according to the IEC908 standard.
To have a data area including a buffer area, and a lead-in area is at least undefined area, and records the copy protection code including time information in the buffer area, and the time information in the lead-in area
An optical disc characterized in that time information of recorded data is temporally discontinuous . 2. An optical disk checking apparatus for determining an optical disk according to claim 1 , wherein the optical disk to be inspected is reproduced and a buffer area and a read area are read.
Reading means for reading the time information of the read area, and wherein the read time information of the two areas is temporally continuous.
Determination means for determining whether or not the time information is discontinuous in time.
An optical disk checking device, wherein an optical disk to be inspected is determined to be a valid optical disk.