Data reproducing method, data reproducing device, data encoding method, data recording method, data recording device, authentication method and semiconductor chip

The present invention relates to a reproduction device for reproducing image or audio data, and more particularly to a data reproduction device and a data recording device for controlling reproduction and / or recording of a recording medium by copy management information.

[0002] A DVD-ROM is a medium having a capacity about 7 times that of a CD-ROM. Not only the program code for PC but also movie software can be recorded by compressing video and audio data. DVD-RAM, DVD-R, and DVD-RW are recording media for recording data on DVD. Since a large amount of data can be recorded in these as well, it is necessary to prevent software such as a movie from being digitally copied as it is. For this reason, unauthorized copy protection technology becomes important. This technology is described in "Nikkei Electronics" (1997.8.18 P110 ~ P119) of Nikkei BP.

[0003] Movies and the like recorded on a DVD-Video disc are usually encrypted by the CSS (content scrambling system) method, and even if the data on the disc is copied, it cannot be played unless it is descrambled.

[0004] [Problems to be Solved by the Invention] However, although this describes the reproduction of media on which data is originally recorded, such as a DVD-Video disc, the user can record the data. There is no description about reproduction of the recording medium.

[0005] When reproducing data that has been scrambled differently on a recordable recording medium, it is necessary to determine from which recording medium the reproduced signal is the signal to be descrambling, and the type of data. It is necessary to determine whether the data is copyable data or copy-prohibited data and control each of them.

[Means for Solving the Problems] In order to achieve the above object, the present invention is:<u style="single">When transferring data with an electronic watermark added according to copy control information between devices, the data to be transferred is encrypted by selecting the encryption method corresponding to the data from multiple encryption methods and using the selected encryption method. The authentication method corresponding to the selected encryption method is selected from a plurality of authentication methods, the authentication means is switched according to the type of data to perform authentication between the devices, and the data is further added to the data. A data processing method, recording device, compressed data decoding device, and data processing device characterized in that the electronic watermark is detected and data processing is performed according to the copy control information of the detected electronic watermark.</u>To.

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

[0008] FIG. 1 shows an embodiment of a reproduction device for reproducing data including copy control information according to the present invention. This embodiment shows a recordable medium such as a DVD, but of course, this is not limited to an optical disc, but applies to all media for storing data.

In the figure, 1 is a data reproduction device 1 and 2, 2 is a reproduction means 1, 3 is a switching SW1, 4 is an authentication means 1a, 5 is an authentication means 2a, 6 is an authentication means 3a, and 7 is a data reproduction device 2. 8 is authentication means 1b, 9 is authentication means 2b, 10 is authentication means 3b, 11 is decryption means 1, 12 is decryption means 2, 13 is switching SW2, 14 is WM detection means, 15 is MPEG playback means, 16 Is data input, 17 is data output, 18 is data bus 1, 19 is authentication bus 1, 20 is data bus 2, 21 is authentication bus 2, 22 is data bus 3, 23 is authentication bus 3, 24 is CSS authentication means. a and 25 are CSS data buses, 26 is a CSS authentication bus, 27 is a CSS authentication means b, 28 is a CSS decryption means, 29 is an authentication block 1, and 30 is an authentication block 2.

The operation of this system will be described with reference to FIGS. 1 and 2.

The data input 16 read from the disc by the data reproduction device 1 such as a DVD drive is decoded according to the format recorded by the reproduction means 1. At this time, the type of data, for example, a code indicating the type of recording medium contained in the data (for example, a code indicating whether it is play-only or recordable) and whether the structure of the data is a scrambled structure. Read the code that indicates, video data or audio data, or a code that indicates copy restrictions (for example, a code that indicates copy permission, one-generation copy possible, or copy prohibition). Further, in the case of an optical disc, the type of recording medium may be determined from the tracking signal of the disc. Here, the switching SW1 (3) is switched from these read information, and which authentication means is used is selected. Authentication is performed to confirm the person to whom data is transferred, and key information for decrypting the code is exchanged. The data passed by this key is encrypted, and the key is used to break the code to protect the data.

[0012] The authentication means 1a is, for example, a means for authenticating a playback-only recording medium, and the authentication means 2a is a means for authenticating a recordable recording medium whose copy is restricted by copy restriction information. It is assumed that the authentication means 3a is a recordable recording medium and is a means for authenticating a recording medium whose copy is not restricted by the copy restriction information. The CSS authentication method a (24) is an authentication method for a DVD drive compatible with the current CSS (content scrambling system). Here, in this embodiment, the CSS authentication method a (24) is described independently. This can also be combined with new authentication means 1a, 2a, 3a as in authentication block 1 (29).

[0013] It is assumed that the data reproduction device 2 is, for example, an MPEG board that decodes MPEG data. Authentication means 1b has a relationship corresponding to authentication means 1a, and authentication is confirmed using authentication bus 1 (19), and if it does not correspond, the method for descrambling each is not passed. Do not output data from data bus 1 (18). Similarly, the authentication means 2b and 3b have a relationship corresponding to the authentication means 2a and 3a, and if they do not correspond, the authentication is not performed and the data output is stopped. Here, for the sake of clarity, the authentication bus for authenticating the three sets of authentication means and the data bus for transmitting data from each are independent, but it is also possible to switch between them in one series. .. The CSS authentication means b (27) is an authentication means for the MPEG board corresponding to the current CSS. Here, in this embodiment, the CSS authentication means b (27) is described independently, but this is the authentication block b. It can also be combined with new authentication methods 1b, 2b, and 3b as in (30).

[0014] The data transmitted from the reproduction device 1 to the reproduction device 2 by the data bus 1 is transmitted in a scrambled state in order to prevent copying in the middle of transmission. The types of scramble are the data of the playback-only recording medium and the data of the recordable recording medium whose copy is restricted by the copy restriction information, and the data that is scrambled with different types and can be recorded. So, although the copy is not restricted by the copy restriction information, it is not necessary to protect the data, so it is not scrambled. Therefore, the playback device 1 transmits the type of recording medium and the scrambled state of data by the authentication means. Here, it is not necessary to scramble the disk without copy restriction for copy protection, but if authentication is not performed only in that case, the disk illegally duplicated under the same copy control state as without copy restriction. Since it becomes difficult to detect, authentication should be performed even for disks with no copy restrictions.

[0015] When the authentication is confirmed, the data is transmitted in each scrambled state. The data bus on which the data is transmitted is selected according to the type of recording medium transmitted by the authentication means and the scramble structure of the data, and the decryption means 1 (11) or the decryption means 2 (12) operates accordingly. Then, it is descrambled and sent to the MPEG reproduction means (15) by the switching SW2 (13). The watermark detecting means (14) is an example of a detecting means for detecting additional information embedded in the data decoded by the MPEG reproducing means (15). In this embodiment, the watermark is detected as additional information and copied. If control information is detected, the data output is controlled accordingly. In this embodiment, an example of controlling the output of data by controlling the MPEG reproduction means (15) is shown, but the control method is limited to this, such as stopping the output data or destroying the data on the bus. is not it.

[0016] Here, by incorporating the reproduction means 1 and the switching SW1 (3), the authentication means 1a (4), the authentication means 2a (5), and the authentication means 3a (6) into the same LSI, data can be input from the middle. Making it difficult to retrieve, authentication means 1b (8), authentication means 2b (9), authentication means 3b (10), decryption means 1 (11), decryption means 2 (12), switching SW2 (13), and so on. By incorporating the WM detection means (14) and the MPEG reproduction means (15) in the same LSI, it becomes difficult to extract data from the middle.

FIG. 2 shows a case where the data reproduction device according to the present invention is applied to a DVD drive device. This embodiment shows a recording medium such as a DVD that can be recorded and reproduced, but of course, this is not limited to an optical disc, and applies to all media that can be recorded and reproduced.

In the figure, 24 is a DVD disc, 25 is a DVD drive, 26 is a pickup, 27 is a preamplifier, 28 is a system control means 1, 29 is an MPEG playback board, 30 is a system control means 2, 31 is a converter, and 32. Is a monitor.

The signal read from the DVD disc (24) by the pickup (26) is input to the data reproduction device 1 (1) via the preamplifier (27). The data reproduction device 1 (1) is controlled by the system control means 1 (28) and determines the operation state. This is the main operation of the DVD drive (25). The signal reproduced by the data reproduction device 1 (1) is transmitted to the data reproduction device 2 (7). The data reproduction device 2 (7) is controlled by the system control means 2 (30) and determines the operation state. The data reproduced by the data reproduction device 2 (7) is converted by the converter (31), output to the monitor (32), and the image is displayed. This is the main operation of the MPEG playback board (29).

[0020] FIG. 3 shows the structure of sector data of a DVD as an example of data including a code in which the type of recording medium and the scrambled structure of data of the present invention are recorded. On the DVD, identification data called ID and copyright management information called CPR_MAI are written before the main data of 2048 bytes.

[0021] The copyright management information (CPR_MAI) corresponds to both the copyright management information and the regional management information. The read-in area describes whether or not the copyright protection system has a specific data structure (corresponding to the scrambled structure), and whether or not it can be played back in the specified area. In the data area, whether the sector contains or does not contain copyrighted material, has or does not have a specific data structure of the copyright protection system, and has copy restrictions (copy permission, one generation copy possible, copy prohibition). ) Is described.

FIG. 4 shows the structure of DVD identification (ID) data. In the first 4 bytes that make up the sector information, the ID has a code that indicates playback-only data called a data type, or a spare for write-once data and rewrite data.

[0023] In the sector format type, the CLV format type specified for the read-only disc and the write-once disc, or the zone format type specified for the rewrite disc is recorded. In the area type, a data area, a read-in area, a read-out area, and a middle area of a play-only disc are recorded. The data type is read-only data or additional data (link data) and reserve data for rewriting.

[0024] FIG. 5 shows an embodiment of a recording device that records data including copy control information according to the present invention. This embodiment shows a recording medium such as a DVD that can be recorded and reproduced, but of course, this is not limited to an optical disc, and applies to all media that can be recorded and reproduced.

In the figure, 51 is the data recording device 2, 52 is the recording means 1, 53 is the switching SW4, 55 is the authentication means 2d, 56 is the authentication means 3d, 57 is the data recording device 1, 59 is the authentication means 2c, 60 is authentication means 3c, 62 is encryption means 2, 63 is switching SW3, 64 is WM detection means, 65 is MPEG coding means, 66 is data output, 67 is data input, 70 is data bus 2, 71 is authentication. Buses 2 and 72 are data bus 3 and 73 is authentication bus 3.

The data input (67), which is read from the disc by a data playback device 1 such as a DVD drive and is input to the video data or the like output to the monitor, is converted into digital data by the recording means 1 (52). Encoded according to the format for recording. At this time, a code indicating the type of data, for example, the type of recording medium (for example, a code indicating whether it is play-only or recordable) is written according to the format. In addition, as other types of data, for example, a code indicating whether the data structure is encrypted (scrambled) by copy control or a code indicating copy restriction (for example, copy permission, one-generation copy possible, copy prohibition). Write the code). Next, if the data is data for which copy control needs to be performed, scrambling is performed on the recording medium according to the state of copy control. Here, the switching SW3 is switched from the copy control information, and which authentication means is used is selected.

[0027] The watermark detecting means 64 detects copy control information which is additional information added to the data input to the MPEG coding means 65, and performs control according to the information. For example, if the detected information is copy-prohibited information, the output of the recorded data is stopped, and if the detected information is copy-restricted data, the coding process is performed without scrambling. In this embodiment, an example of controlling the output of data by controlling the MPEG coding means 65 is shown, but the control method is not limited to this, such as stopping the output data or destroying the data on the bus. Absent.

[0028] The authentication means 2c is a means for authenticating a recordable recording medium whose copy is restricted by copy restriction information, and the authentication means 3c is a recordable recording medium and copy restriction information. It is assumed that it is a means for authenticating those whose copying is not restricted by.

[0029] Further, although omitted in this embodiment, there is a case where an authentication means corresponding to the current CSS is included as in the playback device, and it is also possible to use this as an authentication block.

[0030] The data recording device 1 is, for example, an MPEG board that encodes MPEG data. Authentication means 2d has a relationship corresponding to authentication means 2c, and authentication is confirmed using 71 authentication bus 2, and if it is not supported, not only is the method for descrambling not passed, but also the method for descrambling is not passed. 70 Do not output data from data bus 2. Similarly, the authentication means 3d has a relationship corresponding to the authentication means 3c, and if it does not correspond, the authentication is not performed and the data output is stopped. Here, for the sake of clarity, the authentication bus for authenticating the two sets of authentication means and the data bus for transmitting data from each are independent, but it is also possible to switch between them in one series. ..

The data transmitted from the data recording device 1 to the data recording device 2 by the data bus 2 is transmitted in a scrambled state in order to prevent copying during transmission. Although the copy is not restricted by the copy restriction information, the data does not need to be copy-protected, so it is not scrambled.

Therefore, the scrambled state of the data is transmitted from the data recording device 1 by the authentication means. The switching SW3 (63) selects either the encryption means 2 according to the data or the path that does not pass through the encryption means so that the scramble can be applied according to the data.

[0033] When the authentication is confirmed, the data is transmitted in each scrambled state. The data bus on which the data is transmitted is selected according to the type of recording medium transmitted by the authentication means and the scramble structure of the data, and is sent to the recording means 1 (52) by the switching SW4 (53).

[0034] Here, the authentication means 2c (59), the authentication means 3c (60), the encryption means 2 (62), the switching SW3 (63) and the WM detection means (64), and the MPEG coding means (65) are the same. By incorporating it in the LSI of, it becomes difficult to retrieve the data from the middle, and the recording means 1 (52), the switching SW4 (53), the authentication means 2d (55), and the authentication means 3d (56) are in the same LSI. By incorporating it, it becomes difficult to retrieve the data from the middle.

FIG. 6 shows another embodiment of a reproduction device for reproducing data including copy control information according to the present invention. This embodiment is the embodiment shown in FIG. 1, and is an example in which the data bus and the authentication bus are shown independently and are used in combination. Those with the same number as in Fig. 1 indicate the same ones.

[0036] In FIG. 6, 70 is a unified data bus, 71 is a unified authentication bus, 72 is a SW for switching the authentication means of the authentication block 1, and 73 is a SW for switching the authentication means of the authentication block 2. Is. With such a configuration, the data bus and the authentication bus can be shared, and the number of connection lines between devices can be reduced.

FIG. 7 shows a case where the data reproduction device according to the present invention is applied to a DVD drive device and the output signal thereof is connected to another device, for example, a recordable device such as a hard disk. This embodiment shows, for example, a recordable recording medium such as a hard disk, but of course, this is not limited to all recordable media such as a hard disk, and a device that transfers data via a data bus. Applies to the whole. In the figure, 80 is a hard disk device, 81 is a data recording device 1, 82 is a system control means 3, and 83 is a hard disk.

[0038] The signal read from the DVD disc 24 by the pickup 26 is input to the data reproduction device 1 via the preamplifier 27. The data reproduction device 1 is controlled by the system control means 1 and determines the operation state. This is the main operation of the DVD drive 25. The signal reproduced by the data reproduction device 1 is transmitted to the data recording device 1. The data recording device 1 is controlled by the system control means 3 and determines the state of the recording operation. The data reproduced by the data recording device 1 is recorded on the hard disk 83. This is the main operation of the hard disk device 80.

[0039] Here, with respect to a device capable of recording data, it is necessary to perform recording control according to copy control information. Therefore, it is necessary to authenticate the data playback device 1 to the data recording device 1 in order to confirm whether or not the device has a function to control recording correctly. The data to be passed from the data reproduction device 1 to the data recording device 2 should be scrambled to protect the data. Therefore, the data reproduction device 1 and the data recording device 2 are provided with a means for scrambling, a means for descrambling, and a means for passing a key for scrambling. If the authentication fails, the data is not output from the data playback device 1 to the data recording device 2, and even if the data is output, it is scrambled and the key cannot be delivered. , It becomes impossible to reproduce the data correctly. Therefore, even if the scrambled data is recorded by the recording device as it is, it cannot be reproduced correctly.

[0040] Further, here, the case of transferring data to and from the recording device has been described, but similarly, in the case of the playback or output device, it is authenticated whether or not the device correctly performs copy control to protect the data. To do.

[0041] By providing such means and passing data, it is possible to correctly perform copy control of copyrighted data and prevent unauthorized copying and reproduction. ..

FIG. 8 shows a case where the data output device according to the present invention is applied to a monitor. This embodiment shows, for example, an output such as a monitor, but of course, this is not limited to the monitor, but applies to the entire device that transfers data via the data bus. In the figure, 90 is a monitor, 91 is a data processing device 3, 92 is a converter, and 93 is a display device.

[0043] The output is output from the MPEG board 29 to the monitor 90. The data input by the monitor 90 is converted by the converter 31 and output to the monitor 32 to display an image. This is the main operation of the monitor.

[0044] Here, when data is input to the monitor 90 via the data bus 100, the data may be scrambled in order to protect it from being recorded illegally. In that case, the data The processing device 3 descrambles and outputs the data to the converter 92. Therefore, in this case, it is necessary to provide the data processing device 3 with the authentication processing corresponding to the MPEG board 29. In addition, the output from the MPEG board 29 may be output only to a display device such as the monitor 90, and authentication may be performed to confirm that it is not output to the recording device. There is no need to scramble the data when outputting to monitor 90, as it will not be copied illegally.

[0045] By providing such means and passing data, it is possible to correctly perform copy control of copyrighted data and prevent unauthorized copying and reproduction. ..

[0046] FIG. 9 shows a case of a data processing device as a system including a plurality of data processing means (hereinafter referred to as "devices") such as the above-mentioned playback device and recording device, for example, a personal computer. In the personal computer, since the incorporation of each device can be easily changed, the combination is not limited to the combination shown in this embodiment, and includes all combinations of devices for which data is exchanged.

In the figure, 101 is an MPEG board, 102 is an MO drive, and 103 is a digital camera.

[0048] In the personal computer, data is exchanged with each device via the data bus 100. At that time, in order to prevent unauthorized copying on the data bus, authentication is performed with the device connected to the data bus.

[0049] Here, if the authentication is not established, it is determined that the device is a device that does not have the function of correctly performing copy control, and the output of data is stopped. Further, at this time, if the data is only permitted to be reproduced, the recording device is not connected to the data bus, and it is possible to output the data only if the device has a reproduction function.

[0050] Further, when the authentication is not established, the data to be passed may be passed via the data bus only if the data to be passed has no copy restriction.

[0051] These authentications can be performed by a circuit provided in each device, but in the case of a personal computer or the like, the authentication can also be performed by software for controlling each device. It is possible. It is also possible to perform authentication on an OS that controls each device in a centralized manner and control each device according to the authentication result.

[0052] By performing authentication according to the type of data between the devices connected to the data bus in this way and controlling the data transfer according to the result, it is possible to correctly perform copy control. And said.

FIG. 10 shows another embodiment of a reproduction device for reproducing data including copy control information according to the present invention. FIG. 10 shows an example in which what is shown in FIG. 1 is configured in one device, for example, a consumer DVD player. In the case of such a device, it is difficult to rearrange the DVD drive and the MPEG board, so it is not necessary to authenticate. Further, even when these DVD signal processing and MPEG decoding are performed as internal processing of the same LSI, authentication is not required because no other connection or signal is taken out from the data bus. In these cases, it is not necessary to have a plurality of authentication means, and a plurality of encryption decryption means are switched and reproduced.

[Effect of the Invention] According to the present invention, when playing back scrambled data depending on the type of recording medium and copy control information, the authentication means corresponding to each is switched and used. This makes it possible to perform descramble processing according to scrambling. Moreover, since the data that cannot be authenticated is not output, it is possible to prevent the illegally copied data from being recorded and reproduced.

[0055] Further, by incorporating these functions in the same LSI, it is possible to make it difficult to retrieve data from the middle.

BRIEF DESCRIPTION OF THE DRAWINGS [Fig. 1] Fig. 1 is a diagram showing an embodiment of a reproduction device for reproducing data including copy control information according to the present invention.

FIG. 2 is a diagram showing an embodiment when the data reproduction device according to the present invention is applied to a DVD drive device.

FIG. 3 is a diagram showing a structure of sector data of a DVD as an example of data including a code in which a type of recording medium and a scrambled structure of data of the present invention are recorded.

FIG. 4 is a diagram showing a structure of DVD identification (ID) data.

FIG. 5 is a diagram showing an embodiment of a recording device that records data including copy control information according to the present invention.

FIG. 6 shows another embodiment of a reproduction device for reproducing data including copy control information according to the present invention.

FIG. 7 shows a case where a data reproduction device according to the present invention is applied to a DVD drive device and its output signal is connected to a recordable device such as a hard disk.

FIG. 8 shows a case where the data output device according to the present invention is applied to a monitor.

FIG. 9 shows the case of a system including each device according to the present invention, for example, a personal computer.

FIG. 10 shows another embodiment of a reproduction device for reproducing data including copy control information according to the present invention.

[Explanation of code] 1 ... Data playback device 1, 2 ... Playback means 1, 3 ... Switching SW1, 4 ... Authentication means 1a, 5 ... Authentication means 2a, 6 ... Authentication Means 3a, 7 ... Data playback device 2, 8 ... Authentication means 1b, 9 ... Authentication means 2b, 10 ... Authentication means 3b, 11 ... Decryption means 1, 12 ... Encryption Decoding means 2, 13 ... switching SW2, 14 ... WM detection means, 15 ... MPEG playback means, 16 ... data input, 17 ... data output, 18 ... data bus 1, 19 ... Authentication Bus 1, 20 ... Data Bus 2, 21 ... Authentication Bus 2, 22 ... Data Bus 3, 23 ... Authentication Bus 3.