JPH10208384A - Recording medium, and disk cutting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a third person impossible to obtain a key signal directly from a recording medium, by recording a scrambled signal scrambled based on a prescribed key signal and a cryptographic key signal produced by moreover ciphering a key signal generated based on random numbers. SOLUTION: AV data as an original data belonging to a copyright holder 1 is compressed and multiplexed in an authoring studio 2, and is ciphered in a disk cutting factory 2 by a key signal in relation to such a key signal under management by a key signal management agent 4, and then a disk is cut. Thus, the original data cannot be utilized by the outsider even when an illegal copy is made by reproducing the data recorded in the disk, and at the time of manufacturing a cutting data in the disk cutting factory 3, the data is scrambled by a key signal for encipherment.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a DVD, for example.
The present invention relates to a recording medium on which data to be recorded on a (digital video disc) is recorded, and a disc cutting apparatus for creating a master disc based on the data.

[0002]

2. Description of the Related Art FIG. 4 shows a DVD using an encoder for simultaneously encoding video data and audio data.
1 shows a configuration example of an editing system (authoring system). This authoring system uses a digital VTR4
0, an encoder 41 and a computer 42.

The digital VTR 40 is a video reproducing unit 40A for reproducing digital video data from a video tape TP (Tape 1) recorded in a digital system.
And audio tape TP recorded in digital format
(Tape 2) and an audio reproducing unit 40B for reproducing digital audio data.

The encoder 41 encodes video data Dv and audio data Da reproduced from the digital VTR 40 under the control of the computer 42, and further multiplexes the encoded video data and encoded audio data. Output as a series of bit streams.

[0005] Video data Dv and audio data Da are encoded using MPEG2 (Moving Pic).
This is an encoding for data compression by the “Two Experts Group 2”, which is performed according to each algorithm described in the video encoding program and the audio encoding program stored in the main storage device of the computer 42, respectively, and the encoded video is encoded. The multiplexing of the data and the encoded audio data is performed according to an algorithm described in a multiplexing program also stored in the main storage device of the computer 42.

As described above, in this authoring system, the video data Dv and the audio data Dv as the reproduction data from the digital VTR 40 or the like.
a, and converts the video data Dv and the audio data Da to respective predetermined data rates.

The creation of data in such an authoring system is performed in a studio or the like. The data created by the authoring system is recorded on a recording medium, brought to a factory where a cutting machine is located, and both are formatted in a predetermined format. And recording on a recording medium such as a DVD to produce a master disk.

[0008]

However, a third party reproduces signal data from a recording medium such as a disk on which regular signal data is recorded by a genuine maker by using a conventional authoring system and a cutting machine. Thus, even when the reproduced data is copied to a recording medium to generate illegal data, there is a disadvantage that the copying by such illegal data cannot be prevented.

On the other hand, in the prior art, the following 2
One copy countermeasure was taken. The first countermeasure is to invert a specific bit (for example, LSB) of the signal portion during cutting in the cutting machine so as to leave a trace at the time of cutting in the signal portion.
By detecting the trace at the time of this cutting, it is determined whether the signal to be handled is a copied signal or an original signal. It should be noted that the inversion of this specific bit is of such a degree that humans cannot distinguish it.
It has no effect on the image and is used only to determine whether the signal is a copy or an original. However, this specific bit is added later to the original data, and such a determination can be made only by a reproducing device that can detect the inversion of the specific bit. Since it is possible to reproduce the signal without copying, it is not sufficient as a measure against copying.

A second copy countermeasure is a copy restriction based on the SCMS (Single Copy Management System) system adopted in a DAT (Digital Audio Tape) system or the like, in which a digital copy inhibition bit flag is set only once. In this way, copying is permitted only once. However, since copying can be performed only once in such a method, it is not sufficient as a countermeasure for copying.

As described above, the data can be copied relatively easily by comparing the data after the countermeasure with the non-countermeasure data, and comparing the bit arrangement of the control bits between the non-copy guard time and the copy guard time. Means for preventing the copying has been read, and means for invalidating the effect of the copy protection using the reading have appeared. Therefore,
There has been a demand for a copy protection method in which the means for copy protection cannot be determined even if the data contents are read.

The present invention has been made in view of the above points, and provides a recording medium and a disc cutting apparatus that cannot illegally copy reproduced data even if a third party reproduces a disc on which an original signal is recorded. Aim.

[0013]

According to the recording medium of the present invention, when a plurality of material signals are encoded, and when a plurality of encoded material signals are multiplexed and an original signal is newly created, A scrambled signal in which an original signal is scrambled based on a predetermined key signal, and an encrypted key signal obtained by further encrypting the key signal generated based on a random number are recorded.

Further, the disk cutting apparatus of the present invention comprises a key signal generating means for generating a key signal for scrambling the input signal from the input signal based on a random number, and a key signal generating means for generating the key signal based on the key signal. Scrambling means for scrambling, and insertion means for inserting an encrypted key signal obtained by further encrypting the key signal generated based on a random number into the scrambled signal scrambled by the scrambling means, Cutting data is generated from data obtained by inserting the encrypted key signal into the scrambled signal by the inserting means, and a master disk is created based on the cutting data.

According to the recording medium and the disc cutting device of the present invention, the following operations are performed. The recording medium of the present invention records a scrambled signal in which the original signal is scrambled based on a predetermined key signal, and an encrypted key signal obtained by further encrypting the key signal generated based on a random number. As a result, the key signal does not directly go outside, and theft of the key signal can be prevented, whereby unauthorized copying by a third party can be prevented.

In the disc cutting apparatus of the present invention, the key signal generating means generates a key signal for scrambling the input signal from the input signal based on a random number, and the scrambling means generates the key signal based on the key signal. The input signal is scrambled, and the inserting means inserts an encrypted key signal obtained by further encrypting the key signal generated based on the random number into the scrambled signal scrambled by the scrambling means,
By generating cutting data from data obtained by inserting the encrypted key signal into the scrambled signal by the inserting means and creating a master disk based on the cutting data, a key signal is externally output in the disk cutting step. As a result, unauthorized copying by a third party can be prevented.

[0017]

The present embodiment will be described below. In the present embodiment, for example, a third party reproduces data recorded on a package medium such as a DVD with a reproducing apparatus, and copies a reproduced data string as if it were original data and reuses it to prevent unauthorized copying. The original recorded data sequence is scrambled and encrypted by a key signal in advance, so that the data sequence cannot be reused if copied by a third party as it is. In particular, in order to protect the confidentiality of the key signal related to encryption, it is important to transfer and manage the key signal. In this embodiment, the confidentiality is effectively maintained.

In this embodiment, in such a copy protection measure, the original data string is encrypted. For example, in a disc cutting factory, the passed data string is scrambled in accordance with the key signal, and the data string required thereafter is encrypted. A package medium is created by performing appropriate modulation and the like and cutting the master disk. here,
The key signal required for this encryption is not transferred from outside through a human or the like, but is encrypted.For example, in a disk cutting factory, the key signal is automatically generated in a formatter unit. The key signal is prevented from leaking out, the confidentiality of the key signal is further protected, and the key signal is protected against theft by performing copy protection.

As described above, in the case of package media such as DVDs, the reproduced data may be copied by a third party and used separately, and the data provider may be damaged by this. It has become. At this time, it is also necessary to prevent a third party from easily taking measures for copy protection. As a premise of this embodiment, in order to prevent data from being unambiguously decoded even if data is read from a DVD. , CMS (Co
Pyright Management System
m), the original data is encrypted, but this is a key signal, the data is scrambled, and the encryption (encryption) is performed by another means so that the key signal cannot be unambiguously decrypted. ) And then insert it into the data string.

In this embodiment, in such copy protection by the CMS, a closed loop is provided by preventing a key signal necessary for reproducing recorded data into a regular signal from being output to the outside of a formatter section of a disc cutting factory. The processing within the file provides higher confidentiality and makes copy protection more complete.

First, an outline of a copy protection system in a CMS according to the present embodiment will be described with reference to FIG. The copy protection system in the CMS includes a copyright holder 1 for producing AV (audio / video) data as original data, an authoring studio 2 for compressing and multiplexing AV data, and various encryptions related to key signals. It has a key signal management agent 4 for managing related signals, and a cutting disk manufacturing unit (disk cutting factory) 3 for encrypting the compressed AV data with the key signal related signals and then cutting the disk.

The copy protection system in the CMS configured as described above operates as follows. This system is used when creating a package medium such as a DVD with the copyright holder 1's AV data. The authoring studio 2 compresses the AV data as original data owned by the copyright holder 1 in the authoring studio 2. The disk is multiplexed and encrypted by a signal related to the key signal managed by the key signal management agent 4 at the disk cutting factory 3 and then the disk is cut.

As described above, the data recorded on the disc is reproduced by a third party so that even if the original data is copied illegally, it cannot be reused. Therefore, scrambling is performed by a key signal.
Here, in particular, in the present embodiment, the key signal used for the encryption is not output to the outside.

The authoring studio 2 has, for example, an encoding and multiplexing section, an authoring data generating section, and a signal data output circuit. The encoding and multiplexing unit performs encoding for compressing the signal data serving as a plurality of materials supplied from the signal data input unit, and multiplexes the encoded signal data serving as the material, thereby multiplexing the original signal data. It has a function of outputting signal data.

The authoring data generator has a function of inserting a key signal and sectorizing the key signal to a predetermined size to generate authoring data.

The signal data output circuit has a function of recording the signal data supplied from the authoring data generator on a predetermined recording medium and outputting the signal data. The signal data output circuit has a disk output unit, a tape output unit, a hard disk output unit, and an online data output unit. The disk output unit, the tape output unit, the hard disk output unit, and the online data output unit are switched according to the type of the medium on which each output signal is recorded. The disk output unit is used when the recording medium is a disk, and includes a disk recording device. The tape output unit is used when the recording medium is a tape, and is constituted by a tape recording device. The hard disk output unit is used when the recording medium is a hard disk, and includes a hard disk device. The online data output unit is used when the transfer medium is online data, and includes an online cable.

The agent 4 has a function as a key signal-related signal managing means, and has a key signal-related signal generation unit and a key signal-related signal output unit. The key signal-related signal generation unit, and the key signal-related signal output unit,
For example, it has a floppy disk output unit and a keyboard output unit.

The above-mentioned disc cutting factory 3
It has a formatter section and a cutting section. As shown in FIG. 2, the formatter unit 10 according to the present embodiment scrambles AV data supplied from the authoring studio 2 using a key signal generated inside the formatter separately from a key-related signal supplied from the agent 4. A scrambler 11 for a key signal, an encrypted key signal inserter 12 for encrypting the key signal based on information of a key-related signal and inserting an encrypted key signal into scrambled data; A signal converter 13 for converting the scrambled data in which the key signal is inserted into a signal for disk recording.

The formatter unit 10 of the disk cutting factory thus configured operates as follows. A key signal related signal is output from a key signal related signal output unit of the agent 4 in various forms such as a floppy disk, a keyboard, and communication.
Supplied to Also, the compressed AV data is supplied from the authoring studio 2 to the scramble unit 11 using the key signal of the formatter unit in the disc cutting factory.
A key signal to be scrambled is generated in a scrambler 11 using a key signal of the formatter unit, and the signal portion of the data string of the compressed AV data is scrambled using the key signal. The scrambled signal is supplied to the encrypted key signal insertion unit 12. In the encrypted key signal insertion unit 12, the key signal is encrypted (encrypted) based on the key signal related signal of the agent, and the encrypted key signal is inserted into the scrambled data. The scrambled data into which the encrypted key signal is inserted is supplied to a signal converter 13 by a formatter. The scrambled data into which the encrypted key signal has been inserted in the signal converter 13 by the formatter is subjected to signal processing for disk recording.

In this way, since the key signal is generated inside the formatter, the key signal can be generated without passing through the medium, and the key signal which is not encrypted never goes outside. Cannot steal the key signal from the disk recording medium,
The copy protection function using MS can be effectively exhibited.

The above-described disc cutting factory has a formatter section and a cutting section. FIG. 3 shows a configuration of the formatter unit and the cutting unit 20 in the disk cutting factory according to the present embodiment. The formatter unit includes a master key for encrypting a key signal generated inside the format unit from a key signal related signal supplied from the agent 4 and a master key / other CMS system related signal detecting unit 21 for detecting other CMS system related signals. A master key detecting unit 22 that detects a master key from a master key and other CMS system related signals, a random number generating unit 23 that generates a random number, a key signal generating unit 24 that generates a key signal based on the random number,
A scrambled area separating section 26 for separating an area to be scrambled from the compressed AV data supplied from the authoring studio 2, and a compressed AV data of the area to be scrambled generated inside the formatter section based on random numbers. And a scrambler 27 for scrambling with a key signal. The above-described portion corresponds to the key signal scramble unit 11 shown in FIG.

The formatter unit encrypts a key signal generated based on a random number inside the formatter unit using a master key, and a scrambled compressed AV data. Key signal and other CMS
A CMS-related signal / key signal insertion unit 28 for inserting a system-related signal. The portion described above corresponds to the encrypted key signal insertion unit 12 shown in FIG.

Further, the formatter unit adds an error detection code (EDC) and performs an error correction code (ECC) process, and an error detection / error correction code addition unit 29, which is suitable for a signal to be recorded on a disk. Signal processing unit 3 for disc cutting which performs processing such as 16 modulation and synchronous insertion for inserting a synchronization signal including additional information at the beginning of a signal block
0. The above-described portion corresponds to the signal converter 13 using the formatter shown in FIG.

Further, the cutting section has a laser modulator 31 for modulating laser light with data subjected to processing such as 8/16 modulation and synchronous insertion, and a laser beam input to the laser modulator. A cutting laser beam section 32 for cutting a master disk with a modulated laser beam to create a master disk 33 with copy guard.

Next, a detailed configuration of the authoring studio and the disc cutting factory shown in FIG. 1 will be described with reference to FIG. 2 and FIG. First, the authoring studio 2 will be described. The encoding and multiplexing circuit includes an encoding circuit that encodes a video signal, an encoding circuit that encodes an audio signal, an encoding circuit that encodes an auxiliary data signal, an encoded audio signal, an audio signal, and auxiliary data. A multiplexing circuit for multiplexing signals. The encoding circuit, the encoding circuit, and the encoding circuit are MPEG2 (Mo
wing Picture Experts Grou
Encoding for data compression according to p2) is performed. MPE
The G standards include MPEG1 which is a compression encoding standard for storage media such as CD-ROMs, and MPEG2 which is a compression encoding standard for a wide range of applications including MPEG1 applications. In the embodiment, MPEG2 which is most suitable for compressing a moving image of a DVD is used.

The video encoding circuit converts the input signal into a DCT (Dis-
(Crete Cosine Transform) transform, a DCT transform circuit for quantizing DCT-transformed coefficients, an inverse quantizer for inversely quantizing the quantized transform coefficients, and an inverse quantized transform coefficient Inverse DCT
An inverse DCT transform circuit for converting, a motion compensation circuit for performing motion compensation on the inverse DCT transformed signal, an adder for adding the motion compensated signal to the inverse DCT transformed signal, and a motion compensated from the input signal And a subtracter for subtracting the signal.

The audio encoding circuit includes a filter bank for converting a time sample of an input signal into frequency component sub-bands, a bit allocation circuit for bit-allocating the input signal by a psychoacoustic model, and a sub-band for this frequency component. It has a quantization circuit for quantizing each subband and a bit stream forming circuit.

The multiplex circuit includes an encoding circuit,
The encoding circuit and the bit streams of the video, audio and auxiliary data encoded by the encoding circuit are integrated and multiplexed, including synchronization, into one. This multiplexing method includes a program stream (Program stream) constituting one program (program).
am, MPEG2-PS) and a transport stream (trans) that can simultaneously configure a plurality of programs.
port stream, MPEG2-TS). In the present embodiment, MPEG2-PS is used. In this way, the configuration is such that a bit stream of main signal data is generated.

Multiplexing by packets is performed, for example, for video,
When multiplexing signal data such as audio and auxiliary data, each of video, audio, auxiliary data and the like is divided into streams (bit strings) of an appropriate length called packets, and additional information such as a header signal described below is added. In addition, the data packet is appropriately switched to data packets such as video, audio, and auxiliary data, and time-division-divided into a single bit stream. Each of these packets is provided with information for identifying a data attribute such as video, audio, and auxiliary data, which is referred to as a header signal described later, at the beginning.

The packet length depends on the specifications of the storage medium or the transmission network. For example, there is a long one such as an optical disk, and each packet length may be a fixed length or a variable length. In MPEG2-PS (program stream), a layer called a pack layer is provided above data such as video, audio, and auxiliary data, and is usually handled in a unit called a pack in which a plurality of packets are bundled.

The data structure of the multiplexed bit stream thus configured is MPEG2-PS (Progr.
am Stream), and its data structure and bit stream have a hierarchical structure as follows. This bit stream has a large number of 1-bit flags and the like, and is a byte stream that is byte-aligned for each sector unit such as a header signal. Information indicating the length is preceded by a data portion that is not a fixed length. It is configured so that unnecessary parts can be skipped.

The data structure of the multiplex bit stream (MP
EG2-PS) has a lower layer (packet layer) and an upper layer (pack layer). The upper layer (pack layer) is configured as follows. 1
One program is sometimes called a sequence,
Begins with the first pack header and ends with the end code. The pack is generally composed of a plurality of packets, and the pack at the head of the program has an information group called a system header which describes an overview of the entire stream as parameter information. This system header is required to be added to the first pack, but is optional in the second and subsequent packs.

The lower layer (packet layer) is configured as follows. MPEG packet is P
ES (Peckeized Element St)
remPacket), and the structure is MPEG
Since the header part is complicated because it is used in common with 2-TS, it is easy to understand hierarchically. 32
The “packet start code” of bits is composed of a fixed part of 24 bits and a stream ID (identification) part of 8 bits. In MPEG2-PS, a stream ID is defined so that up to 16 channels of video and 32 channels of audio can be obtained at the maximum. The “packet length” following this indicates the data length of the packet following this field. The 2-bit control code following the packet length is MPEG
1 is used for identification.

The authoring data generated in this way is supplied to the signal data and key signal output circuit, and the output unit selected from the disk output unit, the tape output unit, the hard disk output unit, and the online data output unit Is recorded on the corresponding recording medium. Such signal data and data output from the key signal output circuit and recorded on each recording medium are called complete packet data.

Next, referring to FIG. 3, a detailed configuration of the formatter unit in the disk cutting factory will be described. Also,
The master key is uniquely generated by the agent 4, and specifically, is a 5-byte binary number and is mapped by 8 bits. The master key detection unit 22 supplies an 8-bit numerical value from the agent 4. Receive it and convert it to a specific 5-byte number to generate a master key.

In a normal CMS, there are a title key for scrambling data, a (master) disc key for encrypting the title key, and an authentic control code for collation for exchanging data between personal computers (PC), for example.

The CMS system related signal of the present embodiment is supplied from the agent 4 to the master key / other CMS system related signal detecting section 21 as a (master) disk key. The title key (key signal) is generated in the key signal generation unit 24 of the formatter unit. Then, the master key is detected by the master key detection unit 22, and the title key (key signal) is encrypted by the master key in the key signal encryption unit 25.

More specifically, in the key signal encryption unit 25, the disk key is a master key (400
The key is inserted into the scrambled signal in the CMS-related signal / key signal insertion unit 28 as an encrypted disk key. Then, the encrypted disk key is recorded on the disk and goes outside.

At the time of reproduction, in the disc player, the encrypted disc key is collated with the master key in the IC supplied and authorized by the agent 4 containing all the master keys, and is taken out as a raw disc key. Then, a raw title key (key signal) is derived from the encrypted title key similarly embedded in the data, and the data is descrambled with this title key.

In the above description, the (master) disk key is simplified and described using only the master key. The key signal generated by the key signal generation unit 24 is, for example, a 5-byte binary number.

In the key signal encryption unit 25, for example, an initial value of scrambling and the number of times of scrambling are derived from the value of the key signal, and are obtained from the values or a specific value is determined by mapping. The key signal encrypted so as not to be read from the outside in the CMS-related signal / key signal insertion unit 28 is, for example, a lead-in part before the data of the scrambled signal in a DVD and a header part of each data packet. Is inserted into.

The scrambled area separating section 26 has a synchronization detecting circuit and a signal separating circuit. The synchronization detection circuit
It has a configuration for detecting a header signal and detecting a synchronization signal included in the header signal. The signal separation circuit separates a signal area to be scrambled based on the synchronization signal.
The process of detecting a header from a bit stream is described below. The data structure of MPEG2 video data has a six-layer hierarchy including a sequence layer, a GOP layer, a picture layer, a slice layer, a macroblock (MB) layer, and a block layer. For picture type, picture is an I picture,
(Intra-frame coded image), P-picture (inter-frame forward prediction coded image), and B-picture (bidirectional prediction coded image). These are PSC (Picture Coding) in the header of the picture layer. Type
e).

The processing for detecting a header from an audio bit stream is described below. The structure of MPEG audio is one of the MPEG audio bit streams.
The frame is converted to AAU (Audio Access Uni)
Called t), the header of the audio data can be detected by detecting the synchronization word of the AAU header.

The processing of the synchronization detection will be described below. Synchronization detection is performed for each access unit. For example, one frame is an access unit for a video signal and one audio frame for an audio signal. The synchronization method of MPEG2 is
Information such as a time stamp indicating when synchronization detection, reproduction, and decoding should be performed is added to each access unit of other data such as a video signal, an audio signal, and an auxiliary data signal.
This time stamp includes SCR (System Cl)
The time reference is given by information such as an ock reference (system time reference value). The time stamp includes PTS (time management information of reproduction output).
And DTS (decoding time management information).

Further, the scrambled area separating section 26
The video signal, the audio signal, and the auxiliary data signal are configured to be separated into individual bit streams from the bit stream. The scrambled area separating section 26 is a demultiplex circuit, and is a circuit that performs the reverse operation of the multiplex circuit.

This error correction code has a CIRC (C
Ross Interleaved Reed Sol
omon Code).

The sector detector 34 is configured to generate each signal in units of signal blocks into which the header signal is inserted, that is, in units of sectors.

The disk-cutting signal processing section 30 processes the input data signal such as 8/16 modulation for a disk and outputs it. Here, the 8/16 modulation circuit is configured to divide the original signal into 8 bits and perform EFMplus modulation for making the recording signal correspond to 16 bits. Further, the laser modulator of the cutting section 31 modulates the cutting laser light according to the output data signal. The cutting laser beam unit 32 irradiates a laser beam modulated based on a signal to form pits on a master disk. The laser beam is composed of an ultraviolet gas laser. Master disk is D
This is the disk that is the master for VD plate making. Although not shown, the master disk is configured to be rotationally driven by a rotational driving means such as a stepping motor during cutting.

The formatter unit and the cutting unit of the disk cutting factory according to the present embodiment configured as described above operate as follows. First, according to the authoring studio in the first stage of the disc cutting factory, the following operation is performed. In the authoring studio 2 shown in FIG. 2, original signal data is supplied to an encoding and multiplexing circuit from a signal data input section for inputting AV data of the copyright holder 1. Specifically, a video signal is supplied from the video signal input unit to the encoding circuit, an audio signal is supplied from the audio signal input unit to the encoding circuit, and an auxiliary data signal is supplied from the auxiliary data signal input unit to the encoding circuit. . In the encoding circuit, the video signal is subjected to moving image compression encoding according to the MPEG2 standard. The audio signal in the encoding circuit is MPE
Audio encoding is performed according to the G2 standard. The auxiliary data signal is subjected to predetermined encoding in the encoding circuit. The signal encoded in each encoding circuit is supplied to a multiplex circuit. In the multiplex circuit, each signal is switched to a packet of data such as video, audio, and auxiliary data, multiplexed in a time division manner, and converted into one bit stream.

In the disk cutting factory shown in FIG. 3, complete packet data recorded and output on the recording medium described above is supplied to the synchronization detecting circuit of the scrambled area separating section 26. In the synchronization detection circuit, a synchronization signal is detected, and a header signal portion is extracted based on the detected synchronization signal.

The bit stream that has been detected in synchronization is supplied to a separation circuit for a signal area to be scrambled.
In the signal separation circuit, individual bit streams of the video signal, the audio signal, and the auxiliary data signal are separated from the multiplexed bit stream. The individual bit streams of the separated video signal, audio signal, and auxiliary data signal are supplied to the scramble unit 27.

In the agent 4, a master key for encrypting a key signal generated inside the format section and other signals related to the CMS system are generated and supplied to the master key / other CMS system related signal detecting section 21 of the formatter section. Master key / Other C
The MS system related signal detection unit 21 detects a master key for encrypting a key signal generated inside the format unit from the key signal related signal supplied from the agent 4 and other CMS system related signals. The master key is supplied to the master key detection unit 22. The master key is detected by the master key detection unit 22.

Further, a random number is generated in the random number generation section 23. The random number is supplied to the key signal generator 24. In the key signal generation unit 24, a key signal is generated based on a random number. The key signal is sent to the key signal encryption unit 25.
And to the scrambler 27. In the scrambler 27, compression A of the area to be scrambled
The V data is scrambled by a key signal generated based on a random number inside the formatter unit.

In the key signal encryption unit 25, the key signal generated based on the random number inside the formatter unit is encrypted by the master key. The encrypted key signal and the scrambled scrambled signal are supplied to the CMS-related signal / key signal insertion unit 28. Further, a CMS-related signal is supplied from the master key / other CMS system-related signal detection unit 21 to the CMS-related signal / key signal insertion unit 28. In the CMS-related signal / key signal insertion unit 28, the encrypted key signal and other CMS system-related signals are inserted into the scrambled compressed AV data.

The scrambled compressed AV data into which the encrypted key signal is inserted is supplied to an error detection / error correction code adding unit 29. In an error detection / error correction code adding section 29, an error detection code (EDC) is added to the data, and an error correction code (ECC) process is performed. The data to which the error detection / error correction code is added is supplied to the signal processing unit 30 for disk cutting. In the disc cutting signal processing unit 30, 8/16 modulation suitable for a signal to be recorded on the disc,
Processing such as synchronous insertion for inserting a synchronization signal including additional information at the head of the signal block is performed. The data on which the signal processing for disk cutting has been performed is supplied to the laser modulator 31.

In the laser modulator 31, the laser modulator operates based on data on which processing such as 8/16 modulation and synchronous insertion has been performed. In this way, a laser beam for cutting modulated by data is supplied to the laser modulator. The cutting laser beam is modulated by a laser modulator to become a laser beam corresponding to the data, and the master disk is cut to create a master disk with copy guard.

Here, as described above, the master key is independently generated by the agent 4, and specifically,
A binary number of bytes, mapped in 8 bits,
The master key detection unit 22 has the agent 4 supply an 8-bit numerical value, which is detected and
Converted to a specific number of bytes to generate a master key.

The signals related to the CMS system according to the present embodiment are,
To the master key / other CMS system related signal detection unit 21 The title key (key signal) is generated in the key signal generation unit 24 of the formatter unit.
Then, the master key is detected by the master key detection unit 22, and the title key (key signal) is encrypted by the master in the key signal encryption unit 25.

More specifically, in the key signal encryption unit 25, the disk key is encrypted using the master key owned by the agent, and the encrypted disk key is used as the encrypted disk key in the CMS-related signal / key signal insertion unit 28. It is inserted into the scrambled signal. Then, the encrypted disk key is recorded on the disk and output to the outside.

At the time of reproduction, in the disc player, the encrypted disc key is collated with the master key inside the IC supplied and authorized by the agent 4 containing all the master keys, and is used as a raw disc key. The title key (key signal) is derived and the data is descrambled.

In the key signal encryption section 25, for example, an initial value of scrambling and the number of times of scrambling are derived from the value of the key signal, and are obtained from the value or determined by mapping to determine a specific value. The description is made to take place.

The CMS-related signal / key signal insertion unit 2
For example, in the case of a DVD, the key signal encrypted so as not to be read from the outside at 8 is inserted into the lead-in part before the data of the scrambled signal and the header part of each data packet.

Also, signal processing 3 for disc cutting
In an 8/16 modulation circuit of 0, an original signal is divided every 8 bits, and an EFM for making a recording signal correspond to 16 bits.
Plus modulation is performed. The signal processed for the disc such as 8/16 modulation is supplied to the laser modulator of the cutting unit. A laser beam to be modulated based on data is supplied to a laser modulator of the cutting unit. In the cutting laser beam section 32, the gas laser light cuts the master disk, and a disk 33 serving as a master for DVD plate making is created. A large number of commercial disks can be created by stamping using the master disk thus created.

As described above, in the present embodiment, the master key for encrypting the key signal and the means 25 for executing the encryption process of the key signal by the master key are provided in advance in the formatter section of the disk cutting factory. At the same time, the key signal is generated by the random number generation unit 23 provided in the formatter unit. The input data string is scrambled in the formatter section of the disc cutting factory by the key signal generated in this way, and the key signal is encrypted by the key signal encryption section 25 using the master key. It is inserted into a predetermined data signal portion, and the encrypted data string is output as a master disk cutting signal through other subsequent signal processing. Here, the random number generation unit 23 and the key signal encryption unit 25 can be configured by hardware, but may be configured by software.

In this case, while the original data string is input, processed by the CMS, and output as a master disk cutting signal to become a disk, the key signal is never output outside the formatter. However, it is not possible to know what the value is from the outside.

As described above, in the CMS of the present embodiment,
The original data sequence is scrambled so that the original data sequence cannot be unambiguously reproduced from the output data, but if the scrambled key signal is known on the playback side, the key signal can be relatively easily To reproduce the original data string.

As described above, in the present embodiment, by preventing the key signal scrambled from the original data string from being output to the outside of the formatter, a third party can know this key signal. Since it is more difficult to perform descrambling, illegal copying can be prevented.

Further, derived from the above, the key signal generator 24 may change the value of the generated key signal to use a plurality of key signals for scrambling. Further, the sector detection section 34 may be provided to change the generated key signal for each sector, for example. By doing so, even if the master key or some key signal supplied from the agent 4 is stolen by a third party, a different key signal for each sector is used for scrambling. The user must perform descrambling while continuously stealing the key signal in accordance with the change, and it becomes difficult to actually perform such plagiarism, which is a very powerful illegal copy prevention measure. Note that such a sector detection unit 3
The sector detection of No. 4 may be performed based on the synchronization detection in the scrambled area separation unit 26.

The disc as a recording medium according to the present embodiment is constructed such that when a plurality of material signals are respectively encoded and a plurality of encoded material signals are multiplexed and an original signal is newly created, Since a signal to be scrambled based on a predetermined key signal and an encrypted key signal obtained by further encrypting the key signal generated based on a random number are recorded, a third party The key signal cannot be directly obtained from the disk as the recording medium, and theft of the key signal, which is likely to occur at the time of passing the key signal, can be prevented. Copying can be prevented.

Further, the disc cutting apparatus of this embodiment comprises a key signal generating means 24 for generating a key signal for scrambling the input signal from an input signal based on a random number, and a key signal generating means 24 for generating a key signal based on the key signal. A scrambler 27 for scrambling the input signal; and an encryption key signal obtained by further encrypting the key signal generated based on a random number.
7. Insertion means 28 for inserting into the scrambled signal scrambled by 7
The cutting data is generated from the data in which the encrypted key signal is inserted into the scrambled signal, and the master disk is created based on the cutting data. In the disc cutting process, no key signal is output to the outside, so that the confidentiality of the key signal can be increased, and a third party cannot obtain the key signal directly from the recording medium, It is possible to prevent key signal plagiarism that is likely to occur when passing key signals,
This has the effect of preventing unauthorized copying of the material signal of the recording medium by a third party.

[0081]

According to the recording medium of the present invention, when a plurality of material signals are respectively encoded and a plurality of encoded material signals are multiplexed and an original signal is newly created,
Since the scrambled signal in which the original signal is scrambled based on a predetermined key signal, and an encrypted key signal obtained by further encrypting the key signal generated based on a random number, are recorded. Cannot obtain the key signal directly from the recording medium, and can prevent theft of the key signal, which is likely to occur at the time of passing the key signal, thereby preventing unauthorized copying of the material signal of the recording medium by a third party. It has the effect of being able to do so.

Further, the disc cutting apparatus of the present invention comprises a key signal generating means for generating a key signal for scrambling the input signal from an input signal based on a random number, and a key signal generating means for generating the key signal based on the key signal. Scrambling means for scrambling, and insertion means for inserting an encrypted key signal obtained by further encrypting the key signal generated based on a random number into the scrambled signal scrambled by the scrambling means, The cutting means generates cutting data from data obtained by inserting the encrypted key signal into the scrambled signal by the inserting means, and creates a master disk based on the cutting data. Automatically generated to remove human intervention Since no key signal is output to the outside in the keying process, the confidentiality of the key signal can be enhanced, and a third party cannot obtain the key signal directly from the recording medium, and this is likely to occur when the key signal is transferred. It is possible to prevent the key signal from being stolen, thereby providing an effect of preventing unauthorized copying of the material signal of the recording medium by a third party.

[Brief description of the drawings]

FIG. 1 is a diagram showing an outline of a copy protection system in a CMS according to an embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration of a formatter unit in a disk cutting factory according to the embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of a formatter unit and a cutting unit in a disk cutting factory according to the embodiment of the present invention.

FIG. 4 is a diagram showing a configuration of a conventional authoring system.

[Explanation of symbols]

1 copyright holder, 2 authoring studio, 3 cutting disc manufacturing (disc cutting factory), 4
Agent, 10 Disk cutting factory formatter, 11 Key signal scramble, 1
2 Encrypted key signal insertion section, 13 signal conversion section by formatter, 20 disk cutting factory formatter section / cutting section, 21 master key / other CMS system related signal detection section, 22 master key detection section, 23 random number generation section, 24 Key signal generation unit, 25 key signal encryption unit, 26 scrambled region separation unit, 27 scramble unit, 28 C
MS-related signal / key signal insertion unit, 29 error detection / error correction code addition unit, 30 disk cutting signal processing unit, 31 laser modulation unit, 32 cutting laser beam generation unit, 33 master disk with copy guard, 34 sector detection Department

Claims (2)

[Claims] 1. A plurality of material signals are respectively encoded,
When a plurality of encoded material signals are multiplexed and an original signal is newly created, the original signal is generated based on a random number and a scrambled signal scrambled based on a predetermined key signal. A recording medium characterized by recording an encrypted key signal obtained by further encrypting a key signal. 2. A key signal generating means for generating a key signal for scrambling the input signal from an input signal based on a random number, and a scrambling means for scrambling the input signal based on the key signal. And inserting means for inserting an encrypted key signal obtained by further encrypting the key signal generated based on a random number into the scrambled signal scrambled by the scrambling means. A cutting apparatus for generating cutting data from data obtained by inserting an encrypted key signal into the scrambled signal, and creating a master disk based on the cutting data.