JP3899699B2 - Optical disc and recording method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an optical disc and a recording method thereof that prevent unauthorized copying of data.
[0002]
[Prior art]
A recording / reproducing apparatus for a recordable phase change optical disc such as a so-called DVD-RAM disc encrypts AV data composed of a video signal, an audio signal, etc., and records it on the optical disc. At the time of reproduction, the original video signal and audio signal can be obtained by decoding the AV data read from the optical disk.
[0003]
For example, as shown in FIG. 14, the recording / reproducing apparatus uses a disk key for encrypting the entire AV data to be recorded on the optical disk, and a sector for encrypting the AV data for each program.・ Encrypt the key. The AV data is encrypted for each program using the encrypted disk key and recorded on the optical disk, and the disk key and the encrypted sector key are also recorded on the optical disk.
[0004]
The recording / reproducing apparatus decrypts the sector key using the disk key and the encrypted sector key at the time of reproduction, and decrypts the AV data encrypted using the sector key. To do.
[0005]
The specific contents of such encryption processing and decryption processing are not disclosed to the public from the viewpoint of preventing unauthorized copying. Therefore, a general user cannot illegally copy AV data unless the configuration of an IC (Integrated Circuit) that performs encryption processing and the like of the recording / playback apparatus is known.
[0006]
In the phase change type optical disc, when the same data is repeatedly recorded at the same place, the recording mark and its periphery deteriorate due to thermal stress or the like. As a result, the optical disc may be limited in characteristics that allow repeated data recording. Therefore, a method of changing the recording position at random, that is, SPS (Start Position Shift method) recording is employed so that the position of the synchronization signal portion having the same signal pattern is not recorded at the same location. Yes.
[0007]
[Problems to be solved by the invention]
However, once the configuration of the IC that performs the encryption processing and the like of the recording / playback device is known, the method of decryption processing for decrypting the encryption is known, so that the AV data recorded on the original optical disc can be stored in other ways. May be copied to other optical discs.
[0008]
Furthermore, as security concerns such as copy protection increase, there is an increasing demand for preventing unauthorized copying not only by encrypting the contents of the optical disk but also by entering individual identification information into the optical disk.
[0009]
The present invention has been proposed in view of such circumstances, and by recording an identification number on an optical disk using SPS recording, the data cannot be reproduced even if the data on the optical disk is illegally copied. An object of the present invention is to provide an optical disc and a recording method thereof.
[0010]
[Means for Solving the Problems]
  In order to solve the above-described problems, an optical disc according to the present invention has a plurality of sectors including a header area and a recording area,At least two recording positions of the predetermined amount of data in the recording area where a predetermined amount of data consisting of a set of data defined on the format is recorded are defined,Recording position of the predetermined amount of data recorded in the recording area for each sectorIndicated by the recording position information that can be distinguished byIdentification informationRecordedIt is characterized by that.
[0011]
  Further, the optical disc according to the present invention has a plurality of segments composed of a header area and a recording area,At least two recording positions of the predetermined amount of data in the recording area for each segment where a predetermined amount of data consisting of a set of data defined on the format is recorded are defined;Recording position of the predetermined amount of data recorded in the recording area for each segmentIndicated by the recording position information that can be distinguished byIdentification informationRecordedIt is characterized by that.
[0012]
  Also,The present inventionIt has a plurality of sectors consisting of a header area and a recording area,At least two recording positions of the predetermined amount of data in the recording area where a predetermined amount of data consisting of a set of data defined on the format is recorded are defined,Recording position of the predetermined amount of data recorded in the recording area for each sectorIndicated by the recording position information that can be distinguished byIdentification informationRecordedoptical diskRecording method,Using the identification information, a first encryption process is performed on a disk key for performing an encryption process on user data of the predetermined amount of data, and the disk on which the first encryption process has been performed is performed. Using the key, the second encryption process is performed on the sector key for performing the encryption process for each program of the user data, and the sector key on which the second encryption process is performed is used. A third encryption process is performed on the user data, and at least the user data subjected to the first to third encryption processes is recorded in a recording area of the optical disc.
[0013]
  Furthermore, the present invention has a plurality of segments each composed of a header area and a recording area, and the recording area for each segment in which a predetermined amount of data consisting of a set of data defined in the format is recorded. At least two recording positions of a predetermined amount of data are defined, and identification information indicated as recording position information that can be discriminated by the recording position of the predetermined amount of data recorded in the recording area for each segment is recorded. A method of recording an optical disk, wherein the identification information is used to perform a first encryption process on a disk key for performing an encryption process on user data of the predetermined amount of data, and the first information Using the encrypted disk key, a second encryption process is performed on the sector key for performing the encryption process for each program of the user data. And performing the third encryption process on the user data using the sector key on which the second encryption process has been performed, and at least the user data on which the first to third encryption processes have been performed Recording is performed in a recording area of the optical disc.
[0014]
In the optical disk recording method according to the present invention, the first encryption process is performed on the disk key for performing the encryption process on the user data of the predetermined amount of data using the identification information of the optical disk, Using the encrypted disk key, the second encryption process is performed on the sector key for performing the encryption process for each program of the user data, and the second encryption process is performed. By using the sector key, the third encryption process is performed on the user data, whereby a different encryption process is performed for each optical disc.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0016]
The present invention is applied to, for example, an optical disc 1 having a configuration as shown in FIG.
[0017]
In the optical disc 1, the data recording surface is divided into radial regions to form a sector structure, and the data recording surface is divided into concentric circles to form a plurality of zones Z0 to Zn.
[0018]
Each sector is assigned to a header area AR1 where the address is written at the head and a recording area AR2 where the remaining area is written. In the recording area AR2, the groove GR is formed to meander. Further, in the track of the innermost zone Z0, the groove GR is formed so as to meander over a predetermined period, and the number of meanders of the groove GR is sequentially increased as it moves to the outer zone. The header area AR1 is discretely arranged on the optical disc, and sector unit address information is recorded. In the header area AR1, a length corresponding to a certain period of the groove GR is assigned.
[0019]
Here, in the first half of the header area AR1, the embossed pit row of the groove header GRH is formed on the track center by the groove GR. In the latter half of the header area AR1, an emboss pit row of the land header LH is formed on the track center by the land.
[0020]
The header area AR1 of the optical disc 1 is composed of “Header 1”, “Gap”, “Header 2”, and “Gap” as shown in FIG. “Header1” corresponds to information by the groove header GRH embossed pit string, and “Header2” corresponds to information by the embossed pit string of the land header LH. “Header1” and “Header2” are “SM” indicating a sector mark, “VFO1” and “VFO2” indicating timing data for synchronization, “AM1” and “AM2” indicating an address mark, and “ID1” indicating an ID. , “ID2” and “PA1” indicating the postamble.
[0021]
In addition, the recording area AR2 of the optical disc 1 is “Guard1” which is a guard area for starting recording, “VFO” which is timing data for synchronization, “SYNC” which indicates the start position of data, and data which is mainly recorded. “DATA”, postamble “PA”, and “Guard2” and “Buffer” which are guard areas for the end of recording.
[0022]
In the recording area AR2, data composed of “VFO”, “SYNC”, “DATA”, “PA” (hereinafter referred to as “recorded data”) is data such as video signal, audio signal AV data, and other synchronization information. It consists of and is frequently rewritten. The recording data has a certain amount of data and is recorded as a unit as shown by hatching in FIG. Each optical disc 1 includes unique identification information (hereinafter referred to as “media ID”). This media ID is specified by the recording position of the recording data in the recording area AR2 for each sector. When the recording data is rewritten, only the recording data itself is rewritten, and the recording position does not change. This prevents the media ID from changing even if the recording data is rewritten. When changing the media ID, the recording position is changed again.
[0023]
The recording of the media ID by shifting the recording position of the AV data in this way is referred to as SPS (Start Position Shift method) recording in the following description.
[0024]
In SPS recording, for example, a 1-bit media ID is recorded in one sector (8 kbytes). For example, as shown in FIG. 2B, in the recording area AR2, the “Guard1” area is small and the “Guard2” area is large, so that the recording data consisting of the above “VFO” and the like is in front of the recording area AR2. It is recorded with a deviation. At this time, the media ID for one bit indicates “0”, for example.
[0025]
Further, as shown in FIG. 2C, when the “Guard1” area is large and the “Guard2” area is small, the recording data composed of the above “VFO” and the like is shifted to the rear of the recording area AR2. Are recorded. At this time, the media ID for 1 bit indicates, for example, “1”. The media ID is specified by collecting these 1-bit information for each sector.
[0026]
Note that all the information of the media ID may be SPS-recorded, or some information of the media ID may be SPS-recorded. In the following description, it is assumed that the media ID consists of 128 bits.
[0027]
For example, all 128-bit information of the media ID is SPS recorded as follows. For example, as shown in FIG. 3A, a 1-bit media ID is recorded in one sector. Since one ECC block is composed of eight sectors, as shown in FIG. 3B, an 8-bit media ID is recorded in one ECC block. Therefore, as shown in FIG. 3C, a 128-bit media ID is recorded in the 16 ECC block.
[0028]
Further, some information of the media ID may be recorded by SPS, and other information of the media ID may be recorded in the recording area AR2. For example, as shown in FIGS. 4A and 4B, 8 bits of the 128-bit media ID may be recorded by SPS, and the remaining 120 bits may be recorded in the recording area AR2. Good.
[0029]
The media ID includes information such as a number unique to the optical disc, an encryption key, a manufacturer of the optical disc 1, a content creator, a signature, and a date.
[0030]
Next, a schematic configuration of the recording / reproducing apparatus 10 that performs encryption processing on the optical disc 1 to record AV data and decrypts the data recorded on the optical disc 1 to reproduce AV data. This will be described with reference to FIG.
[0031]
The recording / reproducing apparatus 10 includes a recording unit 11 that performs encryption processing of AV data and records it on the optical disc 1, and a reproduction unit 15 that performs decryption processing on the AV data reproduced from the optical disc 1.
[0032]
In the recording unit 11, the first encryption circuit 12 encrypts a disk key for encrypting the entire AV data using a media ID unique to the optical disk 1. The second encryption circuit 13 uses the encrypted disk key to perform encryption processing on the sector key for encrypting the AV data for each program. The third encryption circuit 14 encrypts the AV data for each program using the encrypted sector key. The encrypted AV data is recorded on the optical disc 1, and the disc key and the encrypted sector key are also recorded on the optical disc 1.
[0033]
As described above, the recording / reproducing apparatus 10 can perform different encryption processes for each optical disk 1 by performing the AV data encryption process using the media ID unique to the optical disk 1. .
[0034]
On the other hand, in the reproducing unit 15, the first decryption circuit 16 decrypts the encrypted disk key using the media ID of the optical disk 1. The second decryption circuit 17 decrypts the encrypted sector key using this disk key. The third decryption circuit 18 decrypts the AV data encrypted using this sector key. As described above, the recording / reproducing apparatus 10 decrypts the AV data using the media ID of the optical disc 1, so that, for example, even when illegally copied from another optical disc as it is, Since the media ID of the optical disk on which the copied AV data is recorded is different, it is possible to prevent the illegally copied AV data from being decoded.
[0035]
Next, a specific circuit configuration of the recording / reproducing apparatus 20 that records AV data on the optical disc 1 or reproduces the AV data of the optical disc 1 will be described with reference to FIG.
[0036]
The recording / reproducing apparatus 20 includes an optical head 21 for recording / reproducing data via a laser beam, a recording / reproducing circuit 22 for performing predetermined modulation / demodulation processing on AV data, and the AV read from the optical disc 1. An address detection circuit 23 that detects an address of data, a wobble signal detection circuit 26 that detects a wobble signal, a wobbling period detection circuit 27 that detects a period of the wobble signal, and a predetermined clock based on the wobble signal A PLL (Phase Locked Loop) circuit 28, a cluster counter 29 that counts the address position, a system control circuit 30 that controls each circuit, and a ROM 31 that stores predetermined data.
[0037]
The optical head 21 records AV data supplied via the system control circuit 30 and the recording / reproducing circuit 22 on the optical disc 1. Here, the system control circuit 30 performs encryption processing, which will be described later, on the input AV data, and supplies it to the recording / reproducing circuit 22. The recording / reproducing circuit 22 performs error correction code processing, modulation processing, and the like on the data supplied from the system control circuit 30 and then supplies the data to the optical head 21.
[0038]
Further, the optical head 21 described above supplies the detection output of the reflected light from the optical disk 1 of the laser beam to the recording / reproducing circuit 22, the address detecting circuit 23, and the wobble signal detecting circuit 26.
[0039]
The recording / reproducing circuit 22 performs error correction processing, demodulation processing, and the like on the AV data supplied from the optical head 21 and supplies the AV data to the system control circuit 30. The system control circuit 30 performs decoding processing, which will be described later, on the AV data from the recording / reproducing circuit 22 and outputs the result.
[0040]
The address detection circuit 23 decodes address data from the detection output of the optical head 21, detects an error, and the like, and then supplies the decoded address to the cluster counter 29 and the system control circuit 30.
[0041]
The wobble signal detection circuit 26 includes a band pass filter (BPF) 26a for removing a noise component from the wobble signal, and a comparator 26b that performs binarization processing. The BPF 26a is supplied with the detection output (wobble signal) of the groove and / or land recorded on the optical disc 1 via the optical head 21. The BPF 26a removes the noise of the wobble signal and supplies it to the comparator 26b. The comparator 26 b performs binarization processing on the wobble signal from the BPF 26 a to obtain a wobbling detection pulse, and supplies the wobbling detection pulse to the wobbling period detection circuit 27.
[0042]
The wobbling period detection circuit 27 determines the periodicity of the wobbling detection pulse, and supplies it to the PLL circuit 28 if it has a certain periodicity. Note that the servo is being pulled in when it does not have a certain periodicity.
[0043]
The PLL circuit 28 includes a phase comparator 28a, a low pass filter (LPF) 28b that removes high frequency noise components, a voltage controlled oscillator (VCO) 28c, and a frequency divider 28d.
[0044]
The phase comparator 28a compares the phases of the wobbling detection pulse from the wobbling period detection circuit 27 and the pulse from the frequency divider 28d, and supplies a phase comparison error signal indicating the phase error to the VCO 28c via the LPF 28b. To do. The VCO 28 c generates a channel clock (hereinafter referred to as “R / W clock”) based on the phase comparison error signal, and supplies it to the frequency divider 28 d and the cluster counter 29. The frequency divider 28d has a frequency division ratio controlled by the system control circuit 30, divides the R / W clock from the VCO 28c, generates a pulse having the same frequency as the frequency of the wobble signal, and supplies the pulse to the phase comparator 28a. . With this processing, a constant R / W clock is generated based on the wobble signal.
[0045]
As described above, the PLL circuit 28 can generate an accurate R / W clock based on the wobble signal obtained from the optical disc 1, thereby enabling data recording / reproduction with high density without redundancy. become.
[0046]
Based on the address from the address detection circuit 23 and the R / W clock from the VCO 28c, the cluster counter 29 performs synchronization signal processing synchronized with the address cycle and counts the position of the next address. When the cluster counter 29 cannot detect the position of the next address, the cluster counter 29 determines the position of the next address from this counter and counts up the address.
[0047]
The system control circuit 30 controls the rotation of a thread motor (not shown) based on the address detected by the cluster counter 29, accesses the optical head 21 to a predetermined position on the optical disk, and matches the cluster recording / reproduction timing. Data recording and / or reproduction processing. Further, the ROM 31 stores data of the frequency division ratio of the frequency divider 28d corresponding to the address, and the system control circuit 30 controls the frequency division ratio of the frequency divider 28d based on the data of the ROM 31.
[0048]
Further, the system control circuit 30 includes an encryption processing unit 40 illustrated in FIG. 7 for performing the above-described encryption processing, and a decryption processing unit 50 illustrated in FIG. 8 for performing the decryption processing.
[0049]
The encryption processing unit 40 performs encryption processing on the input AV data by using the media ID and the disk key and sector key as encryption keys. The disc key is for encrypting the entire AV data recorded on the optical disc, and the sector key is an encryption key for encrypting the AV data for each program.
[0050]
Here, the encryption processing unit 40 includes a separation circuit 41 that separates the media ID, a timing signal generation circuit 42 that generates an SPS timing signal for SPS recording, and a first encryption that performs disk key encryption processing. The encryption circuit 43, a second encryption circuit 44 for performing sector key encryption processing, and a third encryption circuit 45 for performing AV data encryption processing.
[0051]
The media ID is supplied to the separation circuit 41 and the first encryption circuit 43. Here, the media ID consists of 128 bits, for example, and 8 bits (hereinafter referred to as “media ID1”) are recorded on the optical disc 1 by SPS recording, and the other 120 bits (hereinafter referred to as “the media ID1”). It is assumed that “Media ID 2” is recorded in the recording area AR2.
[0052]
The separation circuit 41 separates the media ID into 8 bits and 120 bits, thereby separating the media ID into an 8-bit SPS recording medium ID1 and a 120-bit recording area AR2 recording medium ID2. Then, the separation circuit 41 supplies the media ID1 to the timing signal generation circuit 42 and supplies the media ID2 to the recording / reproducing circuit 22 shown in FIG.
[0053]
The timing signal generation circuit 42 generates an SPS timing signal for changing the recording position of the recording data in the recording area AR2 based on predetermined data such as an address read from the optical disc 1 and the media ID 1 from the separation circuit 41. The SPS timing signal is output to the recording / reproducing circuit 22.
[0054]
On the other hand, the first encryption circuit 43 encrypts the disk key using the media ID, supplies the encrypted disk key to the second encryption circuit 44, and also records / reproduces the circuit. 22 is supplied.
[0055]
The second encryption circuit 44 encrypts the sector key using the encrypted disk key, and supplies the encrypted sector key to the third encryption circuit 45 and the recording / reproducing circuit 22. To do.
[0056]
The third encryption circuit 45 encrypts AV data including a video signal and an audio signal using the encrypted sector key, and supplies the encrypted AV data to the recording / reproducing circuit 22.
[0057]
Then, the recording / reproducing circuit 22 increases or decreases the data amount of “Guard1” in the recording area AR2 shown in FIG. 2 based on the SPS timing signal supplied from the system control circuit 30. The recording position of recording data such as “VFO” and “DATA” is changed. Thus, by changing the recording position of the recording data, 1-bit media ID is recorded in 1 sector, and 8-bit media ID 1 is recorded in 8 sectors. The recording / reproducing circuit 22 records the media ID 2, the encrypted disk key, the encrypted sector key, and the encrypted AV data as the recording data such as “DATA” shown in FIG. .
[0058]
As described above, the recording / reproducing apparatus 20 can perform the encryption process on the AV data using the media ID unique to the optical disc 1 and record it on the optical disc 1. That is, the recording / reproducing apparatus 20 can record AV data subjected to different encryption processes on each optical disk. Of course, the encrypted disk key and sector key may be recorded as recording data as described above or SPS recording.
[0059]
Here, the case where the media ID and the AV data are simultaneously recorded has been described. However, when the media ID has already been recorded on the optical disc 1, the media ID is read out, and then a predetermined value is determined based on the media ID. Key and AV data encryption processing may be performed. Alternatively, all media IDs may be SPS recorded via the timing signal generation circuit 42 without separating the media IDs.
[0060]
On the other hand, the decryption processing unit 50 receives the media ID 1, media ID 2, encrypted disk key, encrypted sector key, encrypted AV data via the optical head 21 and the recording / reproducing circuit 22. Is supplied. Then, the decryption processing unit 50 can decrypt the encrypted AV data using the media ID 1 or the like.
[0061]
As shown in FIG. 8, the decoding processing unit 50 includes a timing signal generation circuit 51 that generates an SPS timing signal, a media ID1 separation circuit 52 that separates the media ID1 from the SPS timing signal, media ID1 and media ID2. A synthesizing circuit 53 for synthesizing, a first decoding circuit 54 for decoding a disk key, a second decoding circuit 55 for decoding a sector key, and a third decoding circuit 56 for decoding AV data are provided.
[0062]
The timing signal generation circuit 51 generates an SPS timing signal based on the recording position of recording data such as “VFO” and “DATA” in the recording area AR 2 shown in FIG. 2, and supplies this to the media ID 1 separation circuit 52.
[0063]
The media ID 1 separation circuit 52 separates the media ID 1 from the SPS timing signal and supplies it to the synthesis circuit 53.
[0064]
The combining circuit 53 combines the media ID 1 from the media ID 1 separation circuit 52 and the media ID 2 read from the optical disc 1 to generate a media ID, and supplies the media ID to the first decoding circuit 54.
[0065]
The first decryption circuit 54 decrypts the disk key encrypted using the media ID, and supplies the decrypted disk key to the second decryption circuit 55. The second decryption circuit 55 decrypts the encrypted sector key using the decrypted disk key, and supplies the decrypted sector key to the third decryption circuit 56. The third decryption circuit 56 decrypts the encrypted AV data using the decrypted sector key, and outputs the decrypted AV data.
[0066]
As described above, the recording / reproducing apparatus 20 performs the decryption processing of the AV data encrypted using the media ID 1 and the media ID 2 unique to the optical disc 1. Therefore, the recording / reproducing apparatus 20 cannot decode the AV data from the optical disc 1 on which the AV data is illegally copied. Thereby, even if the AV data of one optical disk is illegally copied as it is to another optical disk, the AV data is not decrypted, and as a result, illegal copying can be prevented.
[0067]
In the present embodiment, in the recording / reproducing apparatus 20, the medium ID1 is SPS-recorded and the medium ID2 is recorded as recording data. However, the present invention is not limited to this. For example, media IDs (media ID1 and media ID2) may be SPS recorded on the optical disc 1. At this time, the first decryption circuit 54 reads the encrypted disc key based on the media ID read from the optical disc 1 and supplied via the timing signal generation circuit 51 and the media ID 1 separation circuit 52. Decoding processing may be performed.
[0068]
In the embodiment of the optical disc 1 described above, a 1-bit media ID is recorded in one sector, but the present invention is not limited to this. For example, by distinguishing recording positions of AV data such as “VFO” and “DATA” recorded in the recording area AR2 shown in FIG. 2 into four stages, a 2-bit media ID can be recorded in one sector. . Similarly, a media ID of 3 bits or more can be recorded in one sector.
[0069]
Furthermore, in the embodiment of the optical disc 1 described above, one bit of media ID is recorded in one sector. For example, as shown in FIG. 9, a plurality of segments including a header area AR1 and a recording area AR2 In the optical disc 100 having the above, a recording position of a predetermined amount of data recorded in the recording area AR2 for each segment may indicate identification information, that is, a media ID.
[0070]
The recording / reproducing area of the optical disc 100 is divided into a plurality of concentric zones Z0 to Zn. The same zone is laid out in the form of CAV (Constant Angular Velocity), and the recording density is maximized at the innermost periphery of the same zone, and is gradually reduced toward the outside. The innermost circumference of the adjacent outer peripheral zone is set to be the same as the recording density of the innermost peripheral zone of the adjacent inner peripheral zone.
[0071]
In this optical disc 100, the header area AR1 is laid out in a CAV shape, and one segment from the header area to the header area is one segment. The header area AR1 includes a “VFO” for pulling in the PLL, an address mark, a track address, a segment address, a CRC, and the like.
[0072]
The recording / reproducing data is recorded / reproduced with an error check and correction (ECC) block as one unit, and data of one ECC block is recorded in a plurality of segments.
[0073]
In this optical disc 100, for example, as shown in FIG. 10, 1-bit identification information is constituted by the recording position information of the first segment and the second segment constituting the ECC block.
[0074]
For example, the number of channels to be shifted by SPS (Start Position Shift method) recording is 128 channels, the SPS region of 128 channels is divided into two, the first SPS region is from channel 0 to 64, and from channel 65 to 128 Up to this point is the second SPS region.
[0075]
When both the recording positions of the first segment and the second segment are the same SPS area, the identification information is “0”, and the recording positions of the first segment and the second segment are as shown in FIG. When both are in the first SPS area, or when the recording positions of the first segment and the second segment are both in the second SPS area as shown in FIG. 10B, the identification information is set to “0”.
[0076]
If the recording positions of the first segment and the second segment are different SPS areas, the identification information is “1”, and the recording position of the first segment is the first SPS area as shown in FIG. When the recording position of the second segment is the second SPS area, or when the recording position of the first segment is the second SPS area and the recording position of the second segment is the first SPS area as shown in FIG. The identification information is “1”.
[0077]
The SPS recording position is selected at random. By setting the recording positions of the first segment and the second segment in the ECC block as described above, 1-bit identification information can be composed of two segments. it can.
[0078]
As described above, the optical disc 100 having a plurality of segments each having a header area and a recording area, and the recording position of a predetermined amount of data in the recording area for each segment indicates the identification information, is in accordance with the recording method according to the present invention. The first encryption process is performed on the disk key for performing the encryption process on the user data of the predetermined amount of data using the identification information, and the disk on which the first encryption process is performed The second encryption process is performed on the sector key for performing the encryption process for each program of the user data using the key, and the sector key on which the second encryption process is performed is used. The user data is subjected to a third encryption process, and at least the user data subjected to the first to third encryption processes is recorded.
[0079]
As shown in FIG. 11, 1-bit identification information can also be configured by two ECC blocks.
[0080]
When the recording positions of the odd ECC block and the even ECC block are the same SPS area, the identification information is “0”, and the recording positions of the odd ECC block and the even ECC block are both the first recording position as shown in FIG. In the case of the 1 SPS area, or when the recording positions of the odd ECC block and the even ECC block are both in the second SPS area as shown in FIG.
[0081]
If the recording positions of the odd-numbered ECC block and the even-numbered ECC block are different SPS areas, the identification information is “1”, and the recording position of the odd-numbered ECC block is the first SPS area as shown in FIG. When the recording position of the even ECC block is the second SPS, or when the recording position of the odd ECC block is the second SPS area and the recording position of the even ECC block is the first SPS area as shown in FIG. The identification information is “1”.
[0082]
That is, the recording positions of the segments in the ECC block are the same, and 1-bit identification information is indicated by the recording positions of the odd-numbered ECC block and the even-numbered ECC block.
[0083]
Here, the recording position is detected as follows.
[0084]
That is, as shown in FIG. 12 showing the recording information to the segment, the header area AR1 is composed of “GUARD” and “VFO”, and the data area AR2 is composed of user data including “FRAME SYNC”.
[0085]
“GUARD” is an area for data protection of the phase change recording film including SPS. “VFO” is an area for PLL pull-in. “FRAME SYNC” is a synchronization signal for synchronization.
[0086]
As shown in FIGS. 13A and 13B, the recording position of “FRAMESSYNC” varies depending on the recording position of the SPS. As shown in FIG. 13A, the recording position of the SPS is from 0 to 64 channels. In this case, the recording position of “FRAME SYNC” becomes the SYNC area corresponding to the first SPS. As shown in FIG. 13B, when the recording position of SPS is from 65 channels to 128 channels, the recording position of “FRAME SYNC” is recorded. The position is a SYNC area corresponding to the second SPS. Therefore, when “FRAME SYNC” is detected in the SYNC area corresponding to the first SPS, the recording position of the segment is the first SPS area, and “FRAME SYNC” is detected in the SYNC area corresponding to the second SPS. In the case, the recording position of the segment is the second SPS area.
[0087]
That is, when the recording data includes a synchronization signal, the recording position of the synchronization signal indicates the identification information. Therefore, the identification information can be read by detecting the recording position of the synchronization signal.
[0088]
Note that the number of channels in the area shifted by SPS is not limited to 128 channels, but may be 64 channels or 256 channels depending on the media.
[0089]
【The invention's effect】
As described above in detail, according to the optical disc of the present invention, the recording position of the predetermined data recorded in the recording area for each sector is configured for each sector including the header area and the recording area. By indicating this, identification information unique to each optical disc can be recorded.
[0090]
Further, according to the optical disc of the present invention, each segment composed of a header area and a recording area is configured, and the recording position of predetermined data recorded in the recording area for each segment indicates the identification information. Identification information unique to the optical disc can be recorded.
[0091]
Furthermore, according to the optical disk recording method of the present invention, the first encryption process is performed on the disk key for performing the encryption process on the entire data, using the identification information of the optical disk. The second encryption process is performed on the sector key for performing the encryption process for each program of the data using the processed disk key, and the sector Using the key, the data is subjected to a third encryption process, and the data subjected to the encryption process is recorded in the recording area of the optical disk by recording the data subjected to the encryption process. be able to.
[0092]
In the phase change type optical disc, the reliability including the life of the medium can be improved by adopting SPS (Start Position Shift method) recording in which the recording position is changed at random. Thus, information can be safely recorded. And, by identifying data by at least two recording position information, there is no need to fix the recording position for each recording, and by changing the recording position as originally intended, reliability including the life of the medium can be improved. Can be increased. Further, the identification information can close information bits in an ECC block, and can be completed together with data information in ECC recording units.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining an optical disc to which the present invention is applied.
FIG. 2 is a diagram for explaining the format of the optical disc.
FIG. 3 is a diagram for explaining a media ID recorded on the optical disc.
FIG. 4 is a diagram for explaining a media ID recorded on the optical disc.
FIG. 5 is a schematic block diagram of an optical disc recording / reproducing apparatus to which the present invention is applied.
FIG. 6 is a block diagram showing a specific circuit configuration of the optical disc recording / reproducing apparatus.
FIG. 7 is a block diagram showing a configuration of an encryption processing unit of a system control circuit of the recording / reproducing apparatus.
FIG. 8 is a block diagram showing a configuration of a decoding processing unit of the system control circuit.
FIG. 9 is a diagram for explaining another example of an optical disc to which the present invention is applied.
10 is a diagram for explaining a method for indicating identification information at recording positions of two segments constituting an ECC block in the optical disc shown in FIG. 9;
11 is a diagram for explaining a method for indicating identification information at recording positions of two ECC blocks on the optical disc shown in FIG. 9; FIG.
12 is a diagram for explaining the recorded contents of segments in the optical disc shown in FIG. 9; FIG.
13 is a diagram for explaining a method for detecting a recording position indicating identification information in the optical disc shown in FIG. 9; FIG.
FIG. 14 is a schematic configuration diagram of a conventional optical disc recording / reproducing apparatus.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1,100 Optical disk, 20 Recording / reproducing apparatus, 30 System control circuit, 40 Encryption process part, 41 Separation circuit, 42 Timing signal generation circuit, 43 1st encryption circuit, 44 2nd encryption circuit, 45 3rd Encryption circuit

Claims (24)

It has a plurality of sectors each consisting of a header area and a recording area, and the recording position of the predetermined amount of data in the recording area where a predetermined amount of data consisting of a set of data defined in the format is recorded is at least 2. An optical disc characterized in that identification information indicated as recording position information which is defined at two locations and can be discriminated by a recording position of the predetermined amount of data recorded in the recording area for each sector is recorded .   A part of the identification information is specified by a recording position of predetermined data recorded in a recording area for each sector, and the other part of the identification information is recorded in the recording area. The optical disk according to claim 1.   The recording position of the predetermined data indicates identification information of 1 bit or more depending on whether the recording position is shifted to the head side of the recording area or to the rear side of the recording area. 1. The optical disc according to 1.   2. The optical disc according to claim 1, wherein the sector header is composed of a pit address.   2. The optical disk according to claim 1, wherein the sector address is formed by groove and / or land wobbling.   2. The optical disc according to claim 1, wherein the identification information is a unique number.   2. The optical disc according to claim 1, wherein the identification information is an encryption key for performing encryption processing on the data. It has a plurality of sectors each consisting of a header area and a recording area, and the recording position of the predetermined amount of data in the recording area where a predetermined amount of data consisting of a set of data defined in the format is recorded is at least A method for recording an optical disc in which identification information indicated as recording position information defined by two locations and discriminated by a recording position of the predetermined amount of data recorded in a recording area for each sector is recorded ,
Using the identification information, a first encryption process is performed on a disk key for performing an encryption process on user data of the predetermined amount of data, and the disk on which the first encryption process has been performed is performed. Using the key, the second encryption process is performed on the sector key for performing the encryption process for each program of the user data, and the sector key on which the second encryption process is performed is used. 3. A method for recording an optical disc, comprising: performing a third encryption process on the user data and recording at least the user data subjected to the first to third encryption processes in a recording area of the optical disc.   When the timing signal is generated based on the identification information and the predetermined amount of data is recorded, the recording position of the predetermined amount data recorded in the recording area for each sector of the optical disk is changed based on the timing signal. 9. The method of recording an optical disc according to claim 8, wherein the identification information is recorded.   When the timing signal is generated based on a part of the identification information and the predetermined amount of data is recorded, the predetermined amount of data recorded in the recording area for each sector of the optical disk based on the timing signal is recorded. 9. The optical disk recording method according to claim 8, wherein a part of the identification information is recorded by changing a recording position, and another part of the identification information is recorded as the user data in the recording area.   The identification information is read based on a recording position of predetermined data recorded in the recording area for each sector of the optical disc, and the first encryption processing is performed using the read identification information. The optical disk recording method according to claim 8. Recording of the predetermined amount of data in the recording area for each segment having a plurality of segments including a header area and a recording area, and recording a predetermined amount of data consisting of a set of data defined in the format At least two positions are defined, and identification information indicated as recording position information discriminable by a recording position of the predetermined amount of data recorded in the recording area for each segment is recorded. optical disk.   13. The optical disc according to claim 12, wherein 1-bit identification information is constituted by two or more segments.   14. The optical disk according to claim 13, wherein an error correction block is constituted by a plurality of segments, and 1-bit identification information is constituted by two segments in the error correction block.   14. The optical disc according to claim 13, wherein 1-bit identification information is constituted by two error correction blocks.   13. The optical disk according to claim 12, wherein the recording data includes a synchronization signal, and the recording position of the synchronization signal indicates identification information. Recording of the predetermined amount of data in the recording area for each segment having a plurality of segments including a header area and a recording area, and recording a predetermined amount of data consisting of a set of data defined in the format An optical disc recording method in which at least two positions are defined and identification information indicated as recording position information that can be discriminated by the recording position of the predetermined amount of data recorded in the recording area for each segment is recorded. There,
Using the identification information, a first encryption process is performed on a disk key for performing an encryption process on user data of the predetermined amount of data, and the disk on which the first encryption process has been performed is performed. Using the key, the second encryption process is performed on the sector key for performing the encryption process for each program of the user data, and the sector key on which the second encryption process is performed is used. 3. A method for recording an optical disc, comprising: performing a third encryption process on the user data and recording at least the user data subjected to the first to third encryption processes in a recording area of the optical disc.   When the timing signal is generated based on the identification information and the predetermined amount of data is recorded, the recording position of the predetermined amount data recorded in the recording area for each segment of the optical disk is changed based on the timing signal. 18. The optical disc recording method according to claim 17, wherein the identification information is recorded as a result.   When the timing signal is generated based on a part of the identification information and the predetermined amount of data is recorded, the predetermined amount of data recorded in the recording area for each segment of the optical disk based on the timing signal is recorded. 18. The optical disk recording method according to claim 17, wherein a part of the identification information is recorded by changing a recording position, and another part of the identification information is recorded as the user data in the recording area.   The identification information is read based on a recording position of predetermined data recorded in the recording area for each segment of the optical disc, and the first encryption processing is performed using the read identification information. An optical disk recording method according to claim 17.   18. The optical disc recording method according to claim 17, wherein identification information comprising one bit by two or more segments is read from the optical disc, and the first encryption processing is performed using the read identification information. .   An error correction block is constituted by a plurality of segments, identification information in which one bit is constituted by two segments in the error correction block is read from the optical disc, and the first encryption process is performed using the read identification information. The optical disk recording method according to claim 17, wherein:   18. The optical disc recording method according to claim 17, wherein identification information comprising one bit by two error correction blocks is read from the optical disc, and the first encryption processing is performed using the read identification information. .   The recording data includes a synchronization signal, identification information indicated by the recording position of the synchronization signal is detected from the optical disk based on the recording position of the synchronization signal, and the first encryption processing is performed using the detected identification information. 18. The optical disk recording method according to claim 17, wherein

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