AU2006200902B2 - Recording medium with copy protection indicating information and apparatus and methods for forming, recording, reproducing and restricting reproduction of the recording medium - Google Patents

Description

Regulation 3.2 AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Invention Title: Recording medium with copy protection indicating information and apparatus and methods for forming, recording, reproducing and restricting reproduction of the recording medium The following statement is a full description of this invention, including the best method of performing it known to us: RECORDING MEDIUM WITH COPY PROTECTION INDICATING INFORMATION AND APPARATUS AND METHODS FOR FORMING, RECORDING, REPRODUCING AND RESTRICTING s REPRODUCTION OF THE RECORDING MEDIUM 1. TECHNICAL FIELD The present invention relates to a recording medium such as BD-ROM (Blu-ray Disc ROM), which includes copy protection indicating information and an apparatus and methods for 10 forming, recording, reproducing, and restricting reproduction of illegally duplicated recording media. 2. BACKGROUND ART Recently, standardization of a new high-density optical disc, a rewritable Blu-ray disc (BD-RE: Blu-ray Disc 15 Rewritable), have been under development where large quantities of high quality video and audio data can be recorded. Once the standard of a BD-RE has been established, products adopting the new optical discs are expected to be commercially available in the near future. 20 As illustrated in FIG. 1, a BD-RE has an inner hole, clamping area, transition area, BCA (Burst Cutting Area) area, and lead-in area, located in sequential order along radial direction. A data area and lead-out area reside in the center and outermost annulus of the disc, respectively. . 25 The lead-in area is partitioned into a first guard (Guard 1) area, PIC (Permanent Information & Control data) area, a second guard (Guard 2) area, Info 2 area, OPC (Optimum Power Calibration) area, etc. The first guard area and PIC area are 1 A pre-recorded-areas, whereas the remaining lead-in areas, data area, and lead-out area correspond to rewritable areas which can be overwritten with new data. General information of a disc which needs to be 5 permanently preserved may be recorded in the PIC area, which can be encoded in wobbled grooves of a track by HFM (High Frequency Modulation) method. HFM Grooves are modulated in the radial direction with a rather high bandwidth.signal, to create a data channel for replicated information with 10 sufficient capacity and data rate. As shown in FIG. 2, encoding data into wobbled groove can be performed by bi-phase modulation and thus recording. In this modulation method a bit with value 0 is represented by a transition at the start of the bit cell and a 15 bit with value 1 is represented by a transition at the start and in the middle of the bit cell. The modulated bits are recorded on the disc by a deviation of the groove from its average centerline as indicated in the FIG.2. The length of each bit cell shall be 36T, where T corresponds to the length 20 of a channel bit in the Rewritable data areas. Along with the development of a BD-RE, has been the development of a corresponding read-only disc, a.read-only Blu-ray disc (hereinafter, referred to as 'BD-ROM'). As shown in FIG. 3, the BD-ROM disc may include an inner area, clamping 25 area, transition area, information area, and rim area. The main data of an audio/video (A/V) stream recorded in a data zone within an information area can be recorded with encryption with copy protection information (CPI) to prevent unauthorized copy. 30 Various disc information (DI) about the disc,.such as the type of a disc, may be recorded in the PIC area within the information area. When encrypted main data are recorded in the data zone, copy protection information (CPI) for decryption 2.

3 can also be recorded in PIC area. When an optical disc apparatus playing a recording medium performs initial servo operations in accordance with the insertion of a disc, copy protection information (CPI) recorded 5 in the PIC area is detected. If main data recorded in a pre recorded data area is found to be encrypted, the main data is output after decryption using the copy protection information. Even when copy protection information is not recorded in the PIC area because the contents recorded in data area of a BD-ROM 0 are not encrypted, an optical disc apparatus performing initial servo operations still performs a series of operations to detect copy protection information in the PIC area under the assumption that encryption has been applied to the contents. Such a preliminary operation can cause a delay in the playback of 5 actual data. Also, if any data is recorded.on the rewritable disk, i.e., BD-RE, or recordable disk, i.e., BD-WO and its data is copy protected, it has the same problem when the data is reproduced. Furthermore, in case that the copy protection information is '0 not detected, it cannot distinguish whether there is no illegal medium, or there is no copy protection information because the disc is legal and copy-free medium. It is not admitted that any of the information in this specification is common general knowledge, or that the person 25 skilled in the art could be reasonably expected to have ascertained, understood, regarded it as relevant or combined it in anyway at the priority date. DISCLOSURE OF INVENTION In exemplary embodiments, the present invention is directed 30 to a recording medium, such as a high-density and/or read-only recording medium, such as BD-ROM, which includes copy protection indicating information, which can identify whether copy protection information is needed or not for the playback of contents stored in the recording medium, and to methods and 4 apparatuses for forming, recording and reproducing data on the recording medium. In exemplary embodiments, the present invention is directed to a recording medium, such as a high-density and/or read-only 5 recording medium, such as BD-ROM, which includes information in a particular area indicating whether or not copy protection information to encrypt/decrypt recorded contents is present, and to methods and apparatuses for forming, recording, and reproducing data on the recording medium. 0 In exemplary embodiments, the present invention is directed to a recording medium, such as a high-density and/or read-only recording medium, such as BD-ROM, which includes information regarding the presence of copy protection information in the disc information, and to methods and apparatuses for forming, 5 recording, and reproducing data on the recording medium.

5 In accordance with a first aspect of the invention, there is provided a recording medium, comprising: a lead-in area including an identifier to indicate the presence of copy protection information in the recording medium, 5 wherein the copy protection information is required for a copy protection system; and a data area where content data is to be recorded, wherein the lead-in area includes a plurality of information units to control a recording or reproducing of content data to 0 be recorded on the data area of the recording medium, each information unit having a same size, the information units being sequentially arranged on the recording medium, wherein at least the first information unit in sequential order includes the identifier. 5 The plurality of information units may be recorded on the control information area in a phase-modulated wobbled pattern. The recording medium can be an optical disc. In this case, each information unit includes a disc information containing at least disc type information, disc size information, disc 20 structure information, and data zone allocation information. Each information unit may include information having at least the same value as each other. The copy protection information can include a key value for encrypting/decrypting the content data. 25 The copy protection information can be repeatedly recorded in another area of the recording medium other than the first information unit. The identifier may indicate the presence of the copy protection information within one byte in the first control 30 information unit.

6 An area for recording the copy protection information may be filled with value "00" if the identifier indicates the copy protection information is not present. The identifier and the copy protection information may be 5 recorded in a lead-in area of the recording medium, wherein the identifier is followed by the copy protection information. In a second aspect of the present invention there is provided a method of recording data on a recording medium, comprising: 0 (a) generating a plurality of information units to control recording or reproducing of data to be recorded on a recording medium, the plurality of information units being sequentially arranged and including an identifier to indicate the presence of copy protection information in the recording medium, each 5 information unit having a same size, wherein the copy protection information is required for a copy protection system; (b) recording the plurality of information units at a lead in area of the recording medium; and (c) recording content data in a data area of the recording 20 medium, wherein at least the first information unit in sequential order includes the identifier, and the first information unit further includes information on disc size and structures. The recording medium is preferably an optical disc, and each 25 information unit may include disc information containing at least disc type information, disc size information, disc structure information, and data zone allocation information. Each information unit can include information having at least the same value as each other. 30 Step (c) may comprise recording content data in the data area as copy-protected by using a key value of the copy 7 protection information if the identifier indicates the presence of copy protection information. The method may further comprise (d) recording the copy protection information in an area of the recording medium other 5 than the first information unit. Step (d) may record a value "00" in the area where the copy protection information is to be recorded, if the identifier indicates the copy protection information is not present. Step (d) may record the copy protection information 0 repeatedly. Step (b) may record the identifier within one byte in the first control information unit, to indicate the presence of the copy protection information. In accordance with a third aspect of the present invention, 5 there is provided an apparatus for reproducing data from a recording medium, the apparatus comprising: a reading unit configured to read a plurality of information units sequentially arranged in a lead-in area of the recording medium, the plurality of information units including '0 an identifier to indicate the presence of copy protection information, wherein the copy protection information is required for protecting data from being illegally copied, the plurality of information units are required for controlling reproduction of content data recorded on a data area of the recording medium, 25 and each information unit has a same size ; and a controller configured to control the reproduction of the content data based on the identifier in such a manner that the content data is only reproduced using the copy protection information if the identifier indicates that there is the copy 30 protection information, while the content data is reproduced directly without operations to detect copy protection 7a information if the identifier indicates that there is no copy protection information recorded on the recording medium, wherein at least the first information unit in sequential order includes the identifier. 5 As used herein, except where the context requires otherwise the term 'comprise' and variations of the term, such as 'comprising', 'comprises' and 'comprised', are not intended to exclude other additives, components, integers or steps.

4. BRIEF DESCRIPTION OF DRAWINGS The accompanying drawings, which are included to provide a further understanding of the invention, illustrate exemplary embodiments of the invention, and together with the 5 description, serve to explain the principles of the present invention. In the drawings FIG. 1 is a diagram illustrating the disc structure of a conventional rewritable Blu-ray disc (BD-RE); 10 FIG. 2 is a diagram illustrating the high frequency modulation (HFM) groove formed in the PIC area of a rewritable Blu-ray disc; FIG. 3 is a diagram illustrating each area allocated in a read-only Blu-ray disc (BD-ROM) in an exemplary embodiment of 15 the present invention; FIG. 4 is a diagram illustrating an exemplary embodiment wherein information regarding the presence of copy protection information is recorded in the PIC area of a Blu-ray disc according to an exemplary embodiment of the present invention; 20 FIG. 5 is a diagram illustrating the fields of disc information recorded and managed in a high-density Blu-ray disc, wherein a flag indicating the presence of copy protection information is included in an exemplary embodiment of the present invention; 25 FIG. 6 is a diagram illustrating an exemplary embodiment wherein recorded in the BCA area of a Blu-ray disc according to the present invention is information indicating whether or not copy protection information is recorded; FIG. 7 is a diagram illustrating a process restoring data 30 encoded in wobbled pits according to an exemplary embodiment of the present invention; FIG. 8 is a diagram illustrating a simplified structure of an optical disc apparatus capable of playing a high-density 8 Blu-ray disc in accordance with an exemplary embodiment of the present invention; FIG. 9 is a flowchart illustrating the process of playing a high-density Blu-ray optical disc according to an exemplary 5 embodiment of the present invention; and FIGS. 10 and 11 are diagrams illustrating respectively the exemplary embodiments according to the present invention, wherein recorded in a Blu-ray disc are information indicating whether or not copy protection information is recorded. 10 5. MODES FOR CARRYING OUT THE INVENTION Hereinafter, a high-density read-only recording medium according to exemplary embodiments of the present invention and exemplary embodiments of apparatuses and methods for forming, recording, and reproducing copy protection 15 information will be described in detail with reference to the appended drawings. As stated above with reference to FIG. 3, a read-only Blu-ray disc (BD-ROM) according.to exemplary embodiments of the present invention has a disc structure including inner 20 area, clamping area, transition area, information area, and rim area. As shown in FIG. 4, disc information corresponding to general information of a disc as well as encrypted main data recorded in data zone, for example, copy protection 25 information required to decrypt A/V data streams may be recorded in the PIC area allocated in the information area. When the main data is recorded without encryption in the data zone, the copy protection information need not be particularly recorded in the PIC area. 30 Accordingly, a flag to indicate whether or not copy protection information is recorded in the PIC area may be included in the disc information recorded in the PIC area. The 9 flag (CPIrecFlag) indicates the presence of copy protection information and may have a recording size of one byte. As shown in FIG. 5, one byte is allocated to record the flag indicating the presence of copy protection information 5 within the area reserved for the disc information. Also, the disc information in the PIC area can be recorded for several times. The flag byte may be recorded only in the first disc information among multiple of disc information which are recorded repeatedly in the PIC area. 10 As illustrated in FIG. 6, the flag indicating whether or not the copy protection information is recorded may be recorded in another area, e.g., the BCA (Burst Cutting Area) area allocated in the inner ring of the PIC area wherein copy protection information is recorded. 15 Copy protection information, along with the flag indicating the presence thereof, may be encoded and recorded in wobbled pits rather than in straight pits where data.are recorded in general case. To this purpose, pits may be formed in wobbled pattern (or in a zigzag pattern) within as many 20 track sections as needed. Also, it may be encoded and recorded in wobbled pits and straight pits alternatively and/or intermittently within the PIC area. Otherwise, it may be selectively or repeatedly recorded on other area except for the PIC area. It is recorded by HFM groove wobbled method such 25 as BD-RE. The copy protection information includes a key value for encrypting the main data to be recorded on data area. FIG. 7 is a diagram illustrating an example where data is encoded in wobbled pits by bi-phase modulation, whereby data 30 are detected. In FIG. 7, the value of '0101' is encoded in bi phase modulated form, e.g., bi- phase modulated HFM Groove, along with wobbled pattern of wobbled pits. The recording example of wobbled pits in FIG. 7 comprises 36Ts (including 10 marks and.spaces) where six 3T signals (mark) make up of the value of one bit. In the example, left and right transition of a sequence of six pits denoting '1' and'a sequence of six pits denoting '0' are provided in opposite directions. 5 As shown in FIG. 7. the structure by bi-phase modulation is different from the structure illustrated in FIG.2. That is, the method of FIG.2 has a bit with value 0, which is represented by a transition at the start of the bit cell and a bit with value 1, which is represented by a transition at the 10 start and in the middle of the bit cell. Otherwise, the method of FIG.7 has a bit with value 0, which is represented by a transition at the start of low and in the middle of high, and a bit with value 1, which is represented by the transition in the opposite direction. The combination of bits consists of 15 data to detect information recorded as wobbled pit. The wobbled pit can be copy protection information, i.e., key data to decrypt main data recorded on the data zone of the recording medium as shown in FIG.4A to 4F That is, the wobbled pit data can be reproduced or 20 detected only when the bi-phased modulation data is detected or reproduced normally. And also, reproduction or decryption of main data is possible only when the wobbled pit data for copy protection is reproduced or detected using the normally detected or reproduced bi-phase modulation data. 25 When information is recorded in pits, identical pits need not be repeated but modulated varying pits (2T-8T) in accordance with input information may be recorded. In this case, too, however, the position of a pit sequence (namely, phase) is shifted approximately by every 18Ts in order to 30 encode data into wobbled pattern of wobbled pits. The reflected light reflected from wobbled pits recorded in such a manner undergoes a photoelectric transform by four quadrant light receiving elements 13-16. 11 As illustrated in FIG. 7, The photoelectrically transformed electrical signals (Ea, Eb, Ec, Ed) are amplified by a circuit for conventional push-pull track control. More specifically, left and right-side signals of the track (Ea+Eb, 5 Ec+Ed) are amplified by respective amplifiers 10, 11 and the difference signal 501 of the left and right-side signals ((Ea+Eb)-(Ec+Ed)) is output by a differential amplifier 12. When the difference signal.501 -is converted a binary signal based on whether its level is above or below a reference, 10 encoded data in wobbled pattern of wobbled pits may be obtained. Because signals detected.from the wobbled pattern of wobbled pits are not available externally, even if data played from a BD-ROM were copied onto another recording medium other 15 than the BD-ROM, playback of the copied data would be impossible. Instead of recording data in wobbled pattern, if data were recorded in the PIC area according to a different agreement for recording format between manufactures having 20 legal authorities, copying a BD-ROM by unauthorized manufactures can also be made more difficult. FIG. 8 is a simplified diagram illustrating an optical disc apparatus playing a recording medium of a disc. The apparatus includes an optical pickup 11; VDP (Video Disc Play) 25 system 12 performing signal processing and servo control; and a D/A converter 13. The optical disc apparatus may perform playback processing according to whether or not copy protection information is recorded, as described in conjunction with FIG. 9. 30 The VDP system 12 of the disc apparatus detects and checks a flag (CPIrecFlag) indicating whether or not copy protection information among disc information recorded in the PIC area or encoded in the wobbled pits of an inserted BD-ROM 12 is recorded (Sll); otherwise, a flag recorded in the BCA area of a BD-ROM is detected (S11), whereby it is determined whether or not copy protection information is recorded. If the flag is detected, its value is checked (S13). If 5 the value indicates that copy protection information is recorded, the VDP system 12 of the optical disc apparatus performs (S14) the operation of detecting copy protection information recorded in the PIC area or encoded in the wobbled pits; thereafter, by using the copy protection information, a 10 series of data play operations decrypting and playing encrypted data recorded in the data zone are performed (S15). - When the value of the flag indicates the absence of copy protection information or the flag indicating the presence of copy protection information is not detected, the VDP system 12 15 omits unnecessary operations -to detect non-existent copy protection information in the PIC area, but directly performs the operations of reading out recorded contents in the data area. As shown in the exemplary embodiment of PIG. 5, the flag 20 indicating whether or not copy protection information is recorded, instead of being included and recorded in the disc information, may be recorded in the PIC area together with copy protection information. FIG. 10 is an exemplary embodiment illustrating such an 25 arrangement. As shown in the exemplary embodiment of FIG. 10, the flag (CPI-recFlag) indicating the presence of copy protection information may be recorded as header information of copy protection information field. The flag indicating whether or not copy protection 30 information is recorded may have a recording size of one byte. When the value of the flag is '0000 0000', the flag indicates that copy protection information is not recorded (in this case, a succeeding copy protection information field may be filled 13 with '00'.) When the value of the flag is '0000 1111', the flag indicates that copy protection information is recorded. In other exemplary embodiments, copy protection information having a flag indicating whether or not copy 5 protection information is recorded as a header information can be recorded in a particular recording area other than the PIC area, for example, the BCA area. Copy protection information having a flag indicating whether or not copy protection information is recorded can be 10 recorded in a field of disc information stored in the PIC area. Alternatively, it may be recorded as an independent structure from the disc information. FIG. 11 describes an exemplary embodiment wherein copy protection information is recorded in the PIC area 15 independently of the disc information. In the exemplary embodiment of FIG. 11, the flag indicating whether or not copy protection information is recorded also appears in the header of copy protection information. When the value of the flag is '0000 0000', the 20 flag indicates that copy protection information is not recorded (In this case, succeeding copy protection information field may be filled with the value of '00'.) When the value of the flag is '0000 1111', the flag indicates that copy protection information is recorded. 25 As described above, a high-density read-only recording medium and methods for recording copy protection information/playing thereof according to exemplary embodiments of the present invention allows a direct playback of contents stored in a high-density read-only disc unless the contents 30 had been encrypted, whereas proper playback is achieved by reading out decryption.information from the disc when encryption has been applied to the contents. In addition, information for decoding encrypted data is 14 recorded in a form of copy-resistant wobbled pits, whereby illegal copy of the contents stored in a high-density read only disc is prohibited. The foregoing description of exemplary embodiments of the 5 present invention has been presented for purposes of illustration; therefore, those skilled in the art may utilize the invention and various embodiments with improvements, modifications, substitutions, or additions within the spirit and scope of the invention as defined by the following 10 appended claims. 15

Claims (18)

1. A recording medium, comprising: a lead-in area including an identifier to indicate the presence of copy protection information in the recording medium, 5 wherein the copy protection information is required for a copy protection system; and a data area where content data is to be recorded, wherein the lead-in area includes a plurality of information units to control a recording or reproducing of 0 content data to be recorded on the data area of the recording medium, each information unit having a same size, the information units being sequentially arranged on the recording medium, wherein at least the first information unit in sequential order includes the identifier. 5

2. The recording medium of claim 1, wherein the plurality of information units are recorded on the control information area in a phase-modulated wobbled pattern.

3. The recording medium of claim 1, wherein the first information unit further includes information on disc size and 20 structures.

4. The recording medium of claim 1, wherein each information unit includes information having at least the same value as each other.

5. The recording medium of claim 1, wherein the copy 25 protection information includes a key value for encrypting/decrypting the content data. 17

6. The recording medium of claim 6, wherein the copy protection information is repeatedly recorded in an area of the recording medium other than the first information unit.

7. The recording medium of claim 1, wherein the first 5 information unit only includes the identifier, not subsequent information units.

8. The recording medium of claim 1, wherein the copy protection information is recorded in the lead-in area of the recording medium, wherein the identifier is followed by the copy 0 protection information.

9. A method of recording data on a recording medium, comprising: (a) generating a plurality of information units to control recording or reproducing of data to be recorded on a recording 5 medium, the plurality of information units being sequentially arranged and including an identifier to indicate the presence of copy protection information in the recording medium, each information unit having a same size, wherein the copy protection information is required for a copy protection system; 20 (b) recording the plurality of information units at a lead in area of the recording medium; and (c) recording content data in a data area of the recording medium, wherein at least the first information unit in sequential 25 order includes the identifier, and the first information unit further includes information on disc size and structures.

10. The method of claim 9, wherein the first information unit 18 only includes the identifier, not subsequent information units.

11. The method of claim 9, wherein each information unit includes information having at least the same value as each other. 5

12. The method of claim 9, wherein the step (c) records content data in the data area as copy-protected using a key value of the copy protection information, if the identifier indicates the presence of copy protection information.

13. The method of claim 12, further comprising: 0 (d) recording the copy protection information in an area of the recording medium other than the first information unit based on the identifier.

14. The method of claim 13, wherein the step (d) records the copy protection information repeatedly. 5

15. An apparatus for reproducing data from a recording medium, the apparatus comprising: a reading unit configured to read a plurality of information units sequentially arranged in a lead-in area of the recording medium, the plurality of information units including 20 an identifier to indicate the presence of copy protection information, wherein the copy protection information is required for protecting data from being illegally copied, the plurality of information units are required for controlling reproduction of content data recorded on a data area of the recording medium, 25 and each information unit has a same size,; and a controller configured to control the reproduction of the content data based on the identifier in such a manner that the 19 content data is only reproduced using the copy protection information if the identifier indicates that there is the copy protection information, while the content data is reproduced directly without operations to detect copy protection 5 information if the identifier indicates that there is no copy protection information recorded on the recording medium, wherein at least the first information unit in sequential order includes the identifier.

16. The apparatus of claim 15, wherein the first information 0 unit only includes the identifier, not subsequent information units, such that the reading unit reads the identifier from only the first information unit.

17. The apparatus of claim 15, wherein the reading unit is configured to read the identifier and the copy protection 5 information from the lead-in area, the identifier being followed by the copy protection information.

18. The apparatus of claim 15, wherein the copy protection information includes a key value for encrypting/decrypting content data, and the controller is configured to control the 20 reproduction of the content data in such a manner that the content data is decrypted using the key value if the identifier indicates the presence of copy protection information.