JP2005237030A - Information recording method and apparatus, function recording method and apparatus, and information reproducing method and apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an information recording apparatus, function recording apparatus and information reproducing apparatus, capable of specifying a reproducing apparatus more effectively and completely than a scramble system. <P>SOLUTION: In a manufacturing section of an optical disk DK, a scramble function is generated, based on a disk identification code to encrypt a recording signal and record it on the optical disk DK together with the identification code; and a descramble function is transmitted to a memory device 11 in a rental shop together with the identification code. In an IC card issuing machine S2, the disk identification code is read from the optical disk DK, the descramble function is read from the memory device 11, and a deformed descramble function is generated, based on a reproducing apparatus specification code inputted by a demander, and recorded on an IC card C. The demander who takes back the IC card C and the optical disk DK, generates the descramble function from the reproducing apparatus specification codes and the deformed descramble function read from the IC card C, by using a reproducing machine and decrypt the encrypted recording signal. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an information recording method and apparatus, and a function recording method and apparatus for specifying and limiting a reproducing apparatus such as a player to reproduce recording information such as music recorded on an optical disc or the like from other reproducing apparatuses. The present invention also relates to an information reproduction method and apparatus.

Conventionally, a method called a scramble method is generally known as a method for specifying a playback device for playing back recorded information.

This scramble system is a system in which when a digitized recording signal is recorded on an optical disc or the like, the bit string constituting the recording signal is randomly inverted (not scrambled) and recorded. At this time, when the data is scrambled, it is scrambled according to a certain random rule.

When the scrambled recording signal is reproduced, it is reproduced through the descrambling circuit so that the recording signal is unscrambled and the recording signal is reproduced normally. In this case, when a scrambled recording signal is played back by a playback device that does not have a descrambling circuit, the recorded signal is unbearable when the recorded signal is a video signal, and when the recorded signal is an audio signal, only noise is generated. You will not hear it.

According to the scramble system described above, the recording signal can be reproduced only by a reproducing apparatus having a descrambling circuit, so that the reproducing apparatus that should reproduce the recording signal can be specified.

However, according to the conventional scrambling method, normal reproduction can be performed by any reproducing apparatus as long as there is a descrambling circuit. That is, for example, if a descrambling device having a descrambling circuit is connected to a normal playback device (without a descrambling circuit), any playback device can play back, and the recorded signal should be played back. There is a problem that the specification of the playback device may not be effective.

Therefore, the present invention has been made in view of the above-described problems, and its purpose is to more effectively and completely specify a playback device from which a recorded signal is to be played back than a conventional scramble system. The object is to provide an information recording method and apparatus, a function recording method and apparatus, and an information reproduction method and apparatus.

In order to solve the above problems, the invention according to claim 1 is characterized in that the recording is performed in correspondence with an identification code for identifying a recording medium such as an optical disc set in advance or based on the identification code. An encryption function generating step for generating an encryption function for encrypting a recording signal corresponding to recording information to be recorded on the medium, and encrypting the recording signal using the generated encryption function An encryption step for generating a recording signal; a recording step for recording the corresponding identification code together with the encrypted recording signal on the recording medium; and for decrypting the encrypted recording signal based on the encryption function. A decryption function generating step for generating a decryption function and a transmission step for transmitting the decryption function and the corresponding identification code as a set to the outside are configured.

According to the operation of the first aspect of the present invention, in the encryption function generation step, the encryption function is generated in correspondence with the identification code or based on the identification code. Then, in the encryption step, the recording signal is encrypted using the generated encryption function to generate an encrypted recording signal.

Thereafter, in the recording step, the corresponding identification code is recorded on the recording medium together with the encrypted recording signal. In parallel with these, in the decryption function generation step, a decryption function is generated based on the encryption function.

In the transmission step, the decryption function and the corresponding identification code are transmitted to the outside. Therefore, on the receiving side of the decryption function and the corresponding identification code, the decryption function corresponding to the identification code is acquired, and the modified decryption function generated based on the playback device specifying code for specifying the decryption function and the playback device By making it possible to generate a decryption function from a modified decryption function stored in the other storage medium only by a specific playback device in which the playback device specific code is stored in advance. Only by the specific reproducing apparatus, the encrypted recording signal can be decrypted using the decryption function, and the recorded information can be reproduced.

In order to solve the above problems, the invention according to claim 2 is an encrypted recording signal obtained by encrypting a recording signal corresponding to recording information to be recorded on a first recording medium such as an optical disk by an encryption function. A modified decryption function generation for generating a modified decryption function based on a decryption function input from the outside for decryption and a playback device specifying code input from the outside for specifying a playback device that should allow the reproduction of the recorded information And a modified decryption function recording step for recording the modified decryption function on an external second recording medium such as an IC (Integrated Circuit) card.

According to the operation of the second aspect of the invention, in the modified decryption function generation step, the modified decryption function is generated based on the decryption function input from the outside and the playback device specifying code.

Then, in the modified decryption function recording step, the modified decryption function is recorded on the external second recording medium. Therefore, by using the second recording medium, it is possible to generate a decryption function from the modified decryption function recorded on the second recording medium only by a specific playback device in which the playback device specific code is stored in advance. Thus, the recorded information can be reproduced by decrypting the encrypted recording signal using the solution function only by a specific reproducing apparatus.

In order to solve the above problems, the invention according to claim 3 decrypts an encrypted recording signal obtained by encrypting a recording signal corresponding to recording information to be recorded on a recording medium such as an optical disk by an encryption function. A modified decryption function generating step for generating a modified decryption function based on a decryption function input from the outside and a playback device specifying code input from the outside for specifying a playback device that should permit the reproduction of the recorded information; And a modified decryption function recording step for recording the modified decryption function on the recording medium.

According to the operation of the third aspect of the invention, in the modified decryption function generation step, the modified decryption function is generated based on the decryption function input from the outside and the playback device specifying code.

In the modified decryption function recording step, the modified decryption function is recorded on the recording medium. Therefore, by using the recording medium, it is possible to generate a decryption function from a modified decryption function recorded on the recording medium only by a specific playback device in which the playback device identification code is stored in advance. Only the reproducing apparatus can decrypt the encrypted recording signal using the decryption function to reproduce the recorded information.

In order to solve the above problem, the invention according to claim 4 is a first recording medium such as an optical disc in which an encrypted recording signal obtained by encrypting a recording signal corresponding to recording information by an encryption function is recorded in advance. Using a detection step of detecting the encrypted recording signal from, a decryption function for decrypting the encrypted recording signal, and a playback device specifying code for specifying a playback device that should permit playback of the recorded information A decryption function generation step of reading out the modified decryption function from the second recording medium in which the generated modified decryption function is recorded in advance, and generating the decryption function based on the modified decryption function and the playback device specifying code stored in advance. And a decrypting step of decrypting the encrypted recording signal detected using the decryption function and outputting the recording signal.

According to the operation of the fourth aspect of the invention, the encrypted recording signal is detected from the first recording medium in the detection step. In parallel with this, in the decryption function generation step, the modified decryption function is read from the second recording medium in which the modified decryption function is stored in advance, and the decryption function is generated based on the modified decryption function and the playback device identification code.

In the decryption step, the encrypted recording signal detected using the decryption function is decrypted, and the recording signal is output. Therefore, the decryption function is generated based on the modified decryption function recorded on the second recording medium using the pre-stored playback device identification code, and based on this, the encrypted recording signal is decrypted and the recording signal is output. The reproduction apparatus without the reproduction apparatus specific code cannot reproduce the recorded signal, and only the specific reproduction apparatus can decrypt the encrypted recording signal using the decryption function and reproduce the recorded information.

In order to solve the above-mentioned problem, the invention according to claim 5 is directed to a recording medium such as an optical disc in which an encrypted recording signal obtained by encrypting a recording signal corresponding to recording information by an encryption function is recorded in advance. It is generated using a detection process for detecting an encrypted recording signal, a decryption function for decrypting the encrypted recording signal, and a playback device specifying code for specifying a playback device to which playback of the recorded information is permitted. Reading the modified decryption function from the recording medium in which the modified decryption function is recorded in advance, and generating the decryption function based on the modified decryption function and the playback device specifying code stored in advance, A decryption step of decrypting the encrypted record signal detected using a decryption function and outputting the record signal.

According to the operation of the fifth aspect of the invention, the encrypted recording signal is detected from the recording medium in the detecting step. In parallel with this, in the decryption function generation step, the modified decryption function is read from the recording medium in which the modified decryption function is stored in advance, and the decryption function is generated based on the modified decryption function and the playback device identification code.

In the decryption step, the encrypted recording signal detected using the decryption function is decrypted, and the recording signal is output. Accordingly, a decryption function is generated based on the modified decryption function recorded on the recording medium using a pre-stored playback device specific code, and based on this, the encrypted recording signal is decrypted and a recording signal is output. A reproducing apparatus without a specific code cannot reproduce the recorded signal, and only the specific reproducing apparatus can decrypt the encrypted recording signal using the decryption function and reproduce the recorded information.

In order to solve the above problems, the invention according to claim 6 is characterized in that the recording is performed in correspondence with an identification code for identifying a recording medium such as an optical disc set in advance or based on the identification code. Encryption function generation means such as a scramble function generator for generating an encryption function for encrypting a recording signal corresponding to recording information to be recorded on the medium, and the recording signal is encrypted using the encryption function An encryption unit such as a scrambler that outputs an encrypted recording signal, a recording unit such as a recording device that records the identification code corresponding to the encrypted recording signal on the recording medium, and the encryption function. A decryption function generating means such as a descrambling function generator for generating a decryption function for decrypting the encrypted recording signal, and transmitting the decryption function and the identification code to the outside Constructed and a transmitting means such as a transmitting device.

According to the operation of the invention described in claim 6, the encryption function generation means generates an encryption function corresponding to the identification code or based on the identification code, and the encryption function and the decryption function generation means Output.

The encryption unit encrypts the recording signal using the encryption function, and outputs the encrypted recording signal to the recording unit. Thereafter, the recording means records the corresponding identification code together with the encrypted recording signal on the recording medium.

In parallel with these, the decryption function generation means generates a decryption function based on the encryption function and outputs it to the transmission means. Then, the transmission means transmits the decryption function and the corresponding identification code to the outside.

Therefore, on the receiving side of the decryption function and the corresponding identification code, the decryption function corresponding to the identification code is acquired, and the modified decryption function generated based on the playback device specifying code for specifying the decryption function and the playback device By making it possible to generate a decryption function from a modified decryption function stored in the other storage medium only by a specific playback device in which the playback device specific code is stored in advance. Only by the specific reproducing apparatus, the encrypted recording signal can be decrypted using the decryption function, and the recorded information can be reproduced.

In order to solve the above problems, the invention according to claim 7 is an identification code reader for detecting the identification code from the recording medium in which an identification code for identifying a recording medium such as an optical disk is recorded in advance. And the like, a decryption function inputted from the outside for decrypting the encrypted recording signal obtained by encrypting the recording signal corresponding to the recording information to be recorded on the recording medium by the encryption function, and inputted from the outside A storage device such as a memory device for storing the identification code, and a playback device that should permit playback of the decryption function read from the storage device based on the detected identification code and the recording information input from the outside Modified decryption function generation means such as a modified descrambling function generator for generating a modified decryption function based on a playback device identification code for identifying The modified decryption function recording means such as a modified inverted scrambling function recorder for recording 読関 number in an external recording device such as an IC card, and provided with a.

According to the operation of the seventh aspect of the invention, the detection means detects the identification code from the recording medium and outputs it to the modified decoding function generation means. In parallel with this, the storage means stores an identification code and a decryption function inputted from the outside.

Then, in the modified decryption function generation step, a modified decryption function is generated based on the decryption function read from the storage means based on the detected identification code and the playback device identification code, and is output to the modified decryption function recording means.

Thereafter, the modified decryption function record records the modified decryption function in an external recording device. Therefore, by using the recording device, the decoding function can be generated from the modified decoding function recorded in the recording device only by the specific reproducing device in which the reproducing device identification code is stored in advance. Only the playback device can decrypt the encrypted recording signal using the decryption function to reproduce the recorded information.

In order to solve the above problems, the invention according to claim 8 is an identification code reading device for detecting the identification code from the recording medium in which an identification code for identifying a recording medium such as an optical disk is recorded in advance. And the like, a decryption function inputted from the outside for decrypting the encrypted recording signal obtained by encrypting the recording signal corresponding to the recording information to be recorded on the recording medium by the encryption function, and inputted from the outside A storage device such as a memory device for storing the identification code, and a playback device that should permit playback of the decryption function read from the storage device based on the detected identification code and the recording information input from the outside Modified decryption function generation means such as a modified descrambling function generator for generating a modified decryption function based on a playback device identification code for identifying Configured to 読関 number provided with a deformation decryption functions recording means such as a recording head for recording on the recording medium.

According to the operation of the eighth aspect of the invention, the detecting means detects the identification code from the recording medium and outputs it to the modified decoding function generating means. In parallel with this, the storage means stores an identification code and a decryption function inputted from the outside.

In the modified decryption function generation, a modified decryption function is generated based on the decryption function read from the storage means and the playback device identification code based on the detected identification code, and is output to the modified decryption function recording means.

Thereafter, the modified decryption function recording means records the modified decryption function on the recording medium. Therefore, by using the recording medium, it is possible to generate a decryption function from a modified decryption function recorded on the recording medium only by a specific playback device in which the playback device identification code is stored in advance. Only the reproducing apparatus can decrypt the encrypted recording signal using the decryption function to reproduce the recorded information.

In order to solve the above problems, the invention according to claim 9 is directed to a recording medium such as an optical disc in which an encrypted recording signal obtained by encrypting a recording signal corresponding to recording information by an encryption function is recorded in advance. Detection means such as an optical pickup for detecting an encrypted recording signal, a decryption function for decrypting the encrypted recording signal, and a playback device specifying code for specifying a playback device that should permit the playback of the recorded information The modified decryption function generated using the read-out decryption function is read out from a recording device such as an IC card in which the decryption function is recorded in advance, and the decryption function is generated based on the modified decryption function and the pre-stored playback device identification code. Decryption function generation means such as a descrambling function generator, and a reverse scrambling unit that decrypts the encrypted recording signal detected using the decryption function and outputs the recording signal. Constructed and a decoding means, such as Le circuit.

According to the operation of the ninth aspect of the invention, the detecting means detects the encrypted recording signal from the recording medium and outputs it to the decrypting means. In parallel with this, the decryption function generation means reads the modified decryption function from the recording device, generates a decryption function based on the modified decryption function and the playback device specific code, and outputs it to the decryption means.

The decrypting means decrypts the encrypted recording signal detected using the decryption function, and outputs the recording signal. Accordingly, a decryption function is generated based on the modified decryption function recorded in the recording device using the pre-stored playback device specific code, and based on this, the encrypted recording signal is decrypted and the recording signal is output. A reproducing apparatus without a specific code cannot reproduce the recorded signal, and only the specific reproducing apparatus can decrypt the encrypted recording signal using the decryption function and reproduce the recorded information.

In order to solve the above problems, the invention described in claim 10 is related to a recording medium such as an optical disc in which an encrypted recording signal obtained by encrypting a recording signal corresponding to recording information by an encryption function is recorded in advance. Detection means such as an optical pickup for detecting an encrypted recording signal, a decryption function for decrypting the encrypted recording signal, and a playback device specifying code for specifying a playback device that should permit the playback of the recorded information A descrambling function for reading out the modified decryption function from the recording medium in which the modified decryption function generated by using the recording medium is recorded in advance, and generating the decryption function based on the modified decryption function and the pre-stored playback device identification code Decryption function generating means such as a generator, and a descrambling circuit for decoding the encrypted recording signal detected using the decryption function and outputting the recording signal Configured with the and decryption means.

According to the operation of the tenth aspect of the invention, the detecting means detects the encrypted recording signal from the recording medium and outputs it to the decrypting means. In parallel with this, the decryption function generation means reads the modified decryption function from the recording medium, generates a decryption function based on the modified decryption function and the playback device identification code, and outputs it to the decryption means.

The decrypting means decrypts the encrypted recording signal detected using the decryption function, and outputs the recording signal. Accordingly, the decryption function is generated based on the modified decryption function stored in the storage medium using the playback device specific code stored in advance, and the encrypted recording signal is decrypted based on this, and the recording signal is output. A reproducing apparatus without a specific code cannot reproduce the recorded signal, and only the specific reproducing apparatus can decrypt the encrypted recording signal using the decryption function and reproduce the recorded information.

As described above, according to the invention described in claim 1 or 6, the encrypted recording signal is generated using the encryption function and the identification code, and the identification code corresponding to the encrypted recording signal is stored in the recording medium. Since the decryption function for decrypting the encrypted recording signal is transmitted together with the corresponding identification code, the decryption function and the decryption function corresponding to the identification code are obtained on the receiving side of the corresponding identification code. The modified decryption function generated based on the playback device specifying code for specifying the playback device is recorded on another recording medium, and the playback device specifying code is stored in the other storage medium only by the specific playback device in which the playback device specifying code is stored in advance. By enabling the decryption function to be generated from the stored modified decryption function, the encrypted recording signal can be generated using the decryption function only by a specific playback device. And reading, it is possible to reproduce the recorded information.

Therefore, the reproduction apparatus can be specified more effectively and completely. According to the second or seventh aspect of the invention, the modified decryption function is generated based on the decryption function and the playback device specifying code, and is recorded on the external second recording medium (recording device). Using the recording medium (recording apparatus), the decryption function can be generated from the modified decryption function recorded on the second recording medium (recording apparatus) only by the specific reproducing apparatus in which the reproducing apparatus specific code is stored in advance. By doing so, the encrypted recording signal can be decrypted by using the decryption function only by a specific reproducing apparatus, and the recorded information can be reproduced.

Therefore, the reproduction apparatus can be specified more effectively and completely. According to the third or eighth aspect of the invention, the modified decryption function is generated based on the decryption function and the playback device specifying code and is recorded on the recording medium. Encrypted recording signal using a decryption function only by a specific playback device by enabling a decryption function to be generated from a modified decryption function stored in the storage medium only by a specific playback device stored in advance The recorded information can be reproduced and the recording medium for the encrypted recording signal and the recording medium for the modified decryption function can be shared.

Therefore, the reproduction apparatus can be specified more effectively, simply and completely. According to the invention described in claim 4 or 9, the decryption function is generated based on the modified decryption function read from the second recording medium (recording device) and the playback device specifying code stored in advance, and using this Since the encrypted recording signal is decrypted and the recording signal is output, the reproducing device without the reproducing device specific code cannot reproduce the recording signal, and only the specific reproducing device decrypts the encrypted recording signal using the decryption function. The recorded information can be reproduced.

Therefore, the playback device can be specified more effectively and completely. According to the invention described in claim 5 or 10, the decryption function is generated based on the modified decryption function read from the recording medium and the reproduction device specific code stored in advance, and the encryption detected using the decryption function is generated. Since the recording signal is decoded and the recording signal is output, the reproducing device without the reproducing device specific code cannot reproduce the recording signal, and the encrypted recording signal is decrypted using the decryption function only by the specific reproducing device, The recorded information can be reproduced, and the recording medium for the encrypted recording signal and the recording medium for the modified decryption function can be shared.

Therefore, the reproduction apparatus can be specified more effectively, simply and completely.

Next, preferred embodiments of the present invention will be described with reference to the drawings. (I) First Embodiment First, a first embodiment corresponding to the invention described in claims 1, 2, 4, 6, 7, and 9 will be described with reference to FIGS. In the first embodiment, in a so-called rental business in which an optical disc on which recording information including video information is recorded is lent to a consumer, the lent optical disc is reproduced in order to prevent illegal copying or the like in the lent customer. The present invention is applied to the case of specifying a playback device to be specified. (A) Information Recording Apparatus in First Embodiment First, an embodiment of an information recording apparatus corresponding to the first and sixth aspects of the invention will be described with reference to FIG. In the present embodiment, the case where the present invention is applied to an information recording apparatus that records recording information including video information on an optical disk will be described. Among them, it is installed in a manufacturing department that manufactures optical disks on which recording information is recorded.

As shown in FIG. 1, the information recording apparatus S1 of this embodiment includes a video / audio signal source 1 for outputting a recording signal SR composed of a video signal and an audio signal to be recorded on an optical disk DK as recording information, and a recording A disc identification code generator 2 for generating a disc identification code for identifying the optical disc DK on which the signal SR is to be recorded from other optical discs and outputting a corresponding disc identification code signal SI; and a disc identification code signal SI Generating a scramble function as an encryption function for encrypting (scramble) the recording signal SR based on the disc identification code to be generated, and generating a scramble function as an encryption function generating means for outputting the corresponding scramble function signal SF The recording signal SR using the scramble function corresponding to the scramble function signal SF And a scrambler 4 as an encryption means for outputting the encrypted recording signal SRS and a disk identification code signal SI multiplexed with the encrypted recording signal SRS to generate a code multiplexed encrypted recording signal SRSA A formatter 5 for performing a predetermined formatting for recording the code multiplexed encrypted recording signal SRSA on the optical disc DK, and a recording device 6 for recording the formatted code multiplexed encrypted recording signal SRSA on the optical disc DK; Based on the scramble function signal SF, a descrambling function is generated as a decryption function for decrypting the encrypted recording signal SRS encrypted by the scramble function and converting it into the original recording signal SR, and the corresponding descrambling function A descrambling function generator 7 as a decoding function generating means for outputting the signal SRF, and the descrambling A code multiplex descrambling function signal SIF is generated by multiplexing the disc identification code signal SI with the number signal SRF, and the code multiplex descrambling function signal SIF is transmitted to a later-described IC card issuer via a communication line such as a telephone line. It is comprised with the transmitter 8 as a transmission means to perform.

Next, the operation of the information recording apparatus S1 will be described. The recording signal SR output from the video / audio signal source 1 is input to the scrambler 4 and encrypted based on the scramble function corresponding to the scramble function signal SF output from the scramble function generator 3. At this time, since the scramble function is generated differently for each disk identification code based on the disk identification code, the recording signal SR is encrypted with a different scramble function for each disk identification code. Then, the encrypted encrypted recording signal SRS is formatted by the formatter 5 together with the disc identification code corresponding to the scramble function at the time of encryption, and the optical disc DK is passed through the recording device 6 as the code multiplexed encrypted recording signal SRSA. To be recorded.

On the other hand, in parallel with the above operation, the scramble function signal SF is inputted to the descrambling function generator 7 and the encrypted recording signal SRS is decrypted based on the scramble function used for encrypting the recording signal SR. A descrambling function for obtaining the original recording signal SR is generated, and a corresponding descrambling function signal SRF is output. Then, in the transmission device 8, the descrambling function and the disc identification code are multiplexed, output as a code multiplexed descrambling function signal SIF, and transmitted to an IC card issuer described below via a predetermined communication line such as a telephone line. The

In addition, the optical disk DK on which the code multiplexed encryption recording signal SRSA is recorded is copied in large quantities by a replica device (not shown) and is transported to a rental department where an IC card issuing machine described below is installed.

Actually, a plurality of types of optical discs DK corresponding to a plurality of types of recording information are manufactured, and a plurality of types of code multiplex descrambling function signals SIF corresponding to the plurality of types of recording information are provided to the IC card issuer. Sent.

Furthermore, in the above description, the scramble function is exemplified as the encryption function. However, the recording signal SR can be encrypted by a predetermined program corresponding to the scramble function.

In the information recording apparatus S1, the scramble function is generated based on the disc identification code. However, the scramble function is not limited to this and each time a different type of recording signal SR is generated. A different scramble function is generated in the generator 3 and a different disc identification code is generated in the disc identification code generator 2 at the same timing. The scramble function and the disc identification code correspond to the recording signal SR. You may make it transmit to the below-mentioned IC card issuing machine.

Furthermore, in the information recording apparatus S1, the disc identification code generator 2 is provided to generate the disc identification code, and based on this, the scramble function and the descramble function are generated. TOC (Table Of Contents) data peculiar to each type of the recording signal SR included in the recording signal SR is used as a disc identification code for specifying the optical disc DK on which the recording signal SR is recorded. The scramble function and the descrambling function are generated based on the scramble function and the TOC data generated by the recording device 6 on the optical disk DK, and the TOC data and the descrambling function are transmitted to the IC card issuer by the transmitting device 8. It can also be transmitted. In this case, it goes without saying that the disc identification code generator 2 is unnecessary. (B) Function Recording Device in First Embodiment Next, an IC card issuing machine as an embodiment of a function recording device corresponding to the inventions described in claims 2 and 7 will be described with reference to FIG. The IC card issuing machine is actually installed in a rental department (rental store) that lends an optical disk to a consumer in the distribution process of the optical disk.

As shown in FIG. 2, the IC card issuing machine S2 of this embodiment reads the code multiplexed encrypted recording signal SRSA from the optical disk DK on which the code multiplexed encrypted recording signal SRSA is recorded by the information recording apparatus S1 described above. A disk identification code reader 10 serving as a detecting means for extracting a disk identification code from it and outputting a corresponding disk identification code signal SI, and a code multiplexing inverse transmitted from the information recording device S1 via the communication line. A plurality of types of descrambling functions are extracted from the scramble function signal SIF (a plurality of types of code-multiplexed descrambling function signals SIF corresponding to a plurality of types of recording information are transmitted), and are temporarily stored together with the corresponding disc identification codes. And a disc identification code input from the disc identification code reader 10. On the basis of the read signal SI, a memory device 11 serving as a storage means for outputting a descrambling function corresponding to the disc identification code matching the disc identification code signal as a descrambling function signal SRF, and a consumer who borrows the optical disc DK are preset. The playback device specifying code is collated with the recorded content of the playback device specifying code file 13 in which a plurality of playback device specifying codes are recorded in advance. A collator 14 that outputs the reproduction apparatus specific code signal ST only when a reproduction apparatus specific code signal ST corresponding to the reproduction apparatus specific code recorded (registered) in advance is input, the descrambling function signal SRF, and the reproduction apparatus Based on the specific code signal ST, the descrambling function is specified for the playback device. A modified de-scramble function generator 15 serving as a modified decryption function generating means for generating a modified de-scramble function deformed by the mode and outputting a corresponding modified de-scramble function signal SRFX, and a second record of the modified de-scramble function signal SRFX And a modified descrambling function recorder 16 as a modified decryption function recording means for recording on an IC card C as a medium or a recording device.

Next, the operation of the IC card issuing machine S2 will be described. A plurality of types of code-multiplexed descrambling function signals SIF transmitted from the information recording device S1 via the communication line are recorded in the memory device 11, and each descrambling function is stored together with a corresponding disc identification code. On the other hand, the disc identification code read by the disc identification code reader 10 from the optical disc DK recorded with the code multiplexed encryption recording signal SRSA is input to the memory device 11 and stored therein. If a disc identification code that is collated with the disc identification code and is identical to the input disc identification code is stored, a de-scramble function corresponding to the disc identification code is converted into a de-scramble function signal SRF as a modified de-scramble function generator. 15 is output.

In parallel with this, when the consumer inputs a preset playback device specifying code from the keyboard 12, the collator 14 specifies the input playback device specifying code in which a plurality of playback measure specifying codes are registered in advance. Only when a pre-registered reproduction device identification code is input, the reproduction device identification code is output to the modified descrambling function generator 15 as a reproduction device identification code signal ST. Then, the modified descrambling function generator 15 generates a modified descrambling function based on the descrambling function signal SRF and the playback device identification code signal ST, outputs a corresponding modified descrambling function signal SRFX, and modifies the descrambling function. The function recorder 16 records the modified descrambling function signal SRFX on the IC card C. At this time, the modified descrambling function signal SRFX may be recorded on the IC card C as it is, or may be recorded after being randomized or encoded.

Thereafter, the consumer brings back the optical disk DK on which the code multiplexed encryption recording signal SRSA is recorded and the IC card C on which the modified descrambling function signal SRFX is recorded to the installation location of the information reproducing apparatus described below.

As described in the description of the information recording device S1, when the TOC data corresponding to the recording signal SR is used as the disc identification code, the memory device 11 stores the TOC data transmitted together with the descrambling function, Further, the disc identification code reader 10 reads the TOC data from the optical disc DK, and the memory device 11 compares the read TOC data with the TOC data stored in the memory device 11 and compares the TOC data corresponding to the matched TOC data. A scramble function is output. (C) Information Reproducing Apparatus in the First Embodiment Next, a reproducing apparatus as an embodiment of the information reproducing apparatus corresponding to the inventions described in claims 4 and 9 will be described with reference to FIG. Note that this player is actually owned by a consumer in the optical disc distribution process. As shown in FIG. 3, the regenerator S3 of this embodiment is brought back by the consumer as detection means for detecting the code multiplexed encrypted recording signal SRSA from the optical disk DK on which the code multiplexed encrypted recording signal SRSA is recorded. And a reproducing circuit 21 serving as a detecting means for reproducing the detected code multiplex encrypted recording signal SRSA and extracting and outputting the encrypted recording signal SRS from the code multiplex encrypted recording signal SRSA; Read out the modified descrambling function signal SRFX from the IC card C brought back together with the optical disc DK, and the modified inverse scramble function signal SRFX corresponding to the read modified descrambled function signal SRFX. Descramble based on scramble function and stored playback device specific code A de-scrambling function generator 23 as a deciphering function generating means for generating a deciphering function and outputting a de-scramble function signal SRF, and a deciphering of the input encrypted recording signal SRS based on the de-scramble function signal SRF And a descrambling circuit 24 as decoding means for outputting SR.

Next, the operation of the regenerator S3 will be described. The code multiplexed encrypted recording signal SRSA recorded on the brought-back optical disk DK is detected by the pickup 20, from which the encrypted recording signal SRS is extracted by the reproduction circuit 21 and input to the descrambling circuit 24.

In parallel with this, the playback device specifying code stored in advance is read from the playback device specifying code memory 22 and input to the descrambling function generator 23 as the playback device specifying code signal SI. Here, the playback device specifying code stored in the playback device specifying code memory 22 is the same code as that input from the keyboard 12 when lending the optical disk DK in the IC card issuing machine S2. Further, the playback device specifying code memory 22 stores a playback device specifying code unique to the playback device when the consumer purchases the playback device S3. It is configured by a non-rewritable non-volatile memory so that a new playback device identification code cannot be input).

When the playback device specific code signal ST is input and the modified descrambling function signal SRFX is input from the IC card C, the descrambling function generator 23 generates a descrambling function for decrypting the encrypted recording signal SRS. The corresponding descrambling function signal SRF is generated and output to the descrambling circuit 24. At this time, the descrambling function generated by the descrambling function generator 23 is the same as that generated by the descrambling function generator 7 in the information recording apparatus S1.

Thereafter, the descrambling circuit 24 decrypts the encrypted recording signal SRS using the descrambling function corresponding to the descrambling function signal SRF and outputs the original recording signal SR. The video corresponding to the video signal included in the output recording signal SR and the audio corresponding to the audio signal included in the recording signal SR are displayed or output by the monitor receiver 25.

With the above operation, the recording signal SR recorded on the optical disk DK is normally reproduced. As described above, according to the information recording device S1, the IC card issuer S2 and the playback device S3 constituting the first embodiment, the modified descrambling function generated based on the descrambling function and the playback device identification code is used. A player that records on the IC card C, lends the IC card C to the consumer together with the optical disk DK on which the scrambled encrypted recording signal SRS is recorded, and stores the playback device identification code held by the consumer Since the descrambling function can be generated from the modified descrambling function read from the IC card C only at S3, the encrypted recording signal SRS is decrypted and the recording signal SR is output. The recorded signal SR can be reproduced only by the reproducing device S3 having the code, and the specification of the reproducing device is made more effective and complete. It can be carried out.

In the above-described configuration of the playback device S3, the playback device specifying code memory 22 is formed of a non-volatile memory that cannot be additionally written so that the playback device specifying code cannot be additionally registered. The specific code memory 22 can be constituted by a non-volatile memory that can be additionally written, and the playback device specifying code can be additionally written as many times as appropriate to specify the playback device. In this case, the configuration is such that the playback device identification code stored in the past is saved, and the same code as the playback device identification code stored in the past cannot be added. As a result, the optical disk DK registered with the past playback device identification code cannot be played back, and the disadvantage suffered by the consumer is great, so that the illegal copy prevention effect is improved.

In addition, the IC card C may be provided with a timer function, and after the predetermined time has elapsed after storing the modified descrambling function in the IC card issuing machine S2, it is impossible to read the modified descrambling function in the regenerator S3. Also in this case, since the optical disk DK that has passed the return deadline cannot be reproduced, the effect of preventing illegal activities is increased.

Further, in order to prevent illegal modification or the like by the customer, the playback device specific code memory 22 and the descrambling function generator 23 are constituted by an inseparable LSI (Large Scale Integration) circuit, or for the same purpose, It is also possible to incorporate a descrambling function generator 23 in the card C. (II) Second Embodiment Next, a second embodiment corresponding to the invention described in claims 3, 5, 8 and 10 will be described with reference to FIGS. As in the first embodiment, in the second embodiment, in the rental business of an optical disc on which recording information including video information is recorded, the present invention is specified for the case of specifying a playback device that plays back the lent optical disc. It is applied. In the second embodiment, the modified descrambling function is not recorded on the IC card C, but is recorded on a rewritable recording portion such as a magnetic recording band of the optical disc DK.

Moreover, in the following description, the same member number is attached | subjected to the member similar to 1st Embodiment, and the detailed description regarding a structure and operation | movement is abbreviate | omitted. (A) Information recording apparatus according to the second embodiment The information recording apparatus according to the second embodiment is different from the recording area in which the optical disk DK ′ records the code-multiplexed encrypted recording signal SRSA. Since the configuration is the same as that of the information recording apparatus S1 constituting the first embodiment except that a rewritable magnetic recording band of concentric information is provided, the description thereof will be omitted. (B) Function Recording Apparatus in Second Embodiment Next, a disk registration machine as an embodiment of a function recording apparatus corresponding to the inventions described in claims 3 and 8 will be described with reference to FIG. In addition, this disc registration machine can actually rewrite information that is concentric with the recording area in an area other than the recording area for recording the code multiplexed encrypted recording signal SRSA, as compared with the optical disk DK ′. It is installed in a rental department (rental store) that lends a magnetic recording band T).

As shown in FIG. 4, the disk registration device S4 of this embodiment is generated by a modified inverse scramble function generator 15 in place of the modified inverse scramble function recorder 16 in the IC card issuing machine S2 of the first embodiment. A magnetic head 30 is provided as a modified decryption function recording means for recording the modified descrambling function signal SRFX corresponding to the modified descrambling function in the magnetic recording band T of the optical disc DK ′. Since the other configuration is the same as that of the IC card issuing machine S2 of the first embodiment, the detailed description is omitted.

Next, the operation of the disk registration device S4 will be described. In the disk registration device S4, the modified descrambling function signal SRFX corresponding to the modified descrambling function generated by the modified descrambling function generator 15 is magnetically recorded on the magnetic recording band T of the optical disk DK 'by the magnetic head 30. The Since other operations are the same as those of the IC card issuing machine S2 of the first embodiment, detailed description thereof is omitted.

The consumer brings back the optical disk DK 'on which the code multiplexed encrypted recording signal SRSA and the modified descrambling function signal SRFX are recorded to the installation location of the information reproducing apparatus described below. (C) Information Reproducing Apparatus in Second Embodiment Next, a reproducing apparatus as an embodiment of an information reproducing apparatus corresponding to the inventions described in claims 5 and 10 will be described with reference to FIG. This regenerator is owned by the consumer, similar to the regenerator S3 of the first embodiment.

As shown in FIG. 5, the player S5 of the present embodiment was recorded on the magnetic recording band T of the optical disk DK 'brought back by the consumer in place of the IC card C of the player S3 of the first embodiment. A read head 31 for reading the modified descrambling function signal SRFX is provided. Since the other configuration is the same as that of the IC card issuing machine S2 of the first embodiment, the detailed description is omitted.

Next, the operation of the regenerator S5 will be described. In the reproducing apparatus S5, the read head 31 reads the modified descrambling function signal SRFX from the magnetic recording band T of the optical disk DK ', and the descrambling function generator 23 reads the modified descrambling function signal SRFX read by the reading head 31. Based on the playback device specific code signal ST output from the playback device specific code memory 22, a descrambling function is generated and a corresponding reverse scrambling function signal SRF is output to the reverse scrambling circuit 24. Since other operations are the same as those of the regenerator S3 of the first embodiment, detailed description thereof is omitted.

As described above, according to the information recording device S1, the disc registration device S4, and the reproducing device S5 constituting the second embodiment, the modified inverse scramble function signal SRFX is recorded in the magnetic recording band T of the optical disc DK ′. Therefore, it is not necessary to use the IC card C, and the recorded signal SR can be reproduced only by the reproducing device S5 having the reproducing device specifying code as in the first embodiment, and the specification of the reproducing device is made more effective and complete. In addition to the effect that can be easily performed, there is an effect that it is more convenient.

Further, the information recording device S1, the disk registration device S4, and the reproducing device S5 of the second embodiment are also modified as shown in the description of the information recording device S1, the IC card issuing device S2, and the reproducing device S3 of the first embodiment. Is possible. (III) Modified Embodiment of Second Embodiment Next, a modified embodiment of the second embodiment will be described.

The modification of the second embodiment is a form in which the second embodiment is applied to a so-called sold-out optical disc which is not a rental business but a normal sales mode. In the modification of the second embodiment, the modified descrambling function signal SRFX is recorded on a part of the optical disc in a non-rewritable manner. For example, in place of the magnetic recording head 30 in the disk registration device S4 of the second embodiment, a modified descrambling function is printed or stamped on the optical disk by using a printing head by printing. The regenerator is configured to read the modified descramble function printed or stamped by an optical read head instead of the magnetic read head 31 in the regenerator S5 of the second embodiment.

Since other configurations and operations are the same as those in the second embodiment, detailed description thereof is omitted. By configuring as described above, even in the case of the above-mentioned sold-out optical disc, the player can be specified more effectively and completely, similarly to the effect of the second embodiment.

In both the rental optical disc and the sold-out optical disc, the recording format of the modified descrambling function and the recording position on the optical disc are the same, and a rewritable recording band (see T in FIG. 4 or FIG. 5) and an rewritable recording band are used. By using a material (for example, a phase change recording material) that can read the modified inverse scramble function with the same read head, both optical disks can be reproduced by the same player. (IV) Third Embodiment Next, FIG. 6 shows a third embodiment in which the optical disk DK in the first embodiment is applied to a CD-ROM (Compact Disk-Read Only Memory) which is a computer recording medium. It explains using.

In the third embodiment, since the information recording apparatus and the IC card issuing machine are the same as those in the first embodiment, detailed description is omitted. However, in the present embodiment, the recording signal SR is not a recording signal containing video information or music information, but digital data for a computer is encrypted and recorded.

Next, a playback device and a computer according to the third embodiment will be described. In the following description, members similar to those in the first embodiment are denoted by the same member numbers, and detailed description thereof is omitted. As shown in FIG. 6, the regenerator S6 in the third embodiment is digital data. A pickup 20 for detecting the code multiplexed encrypted recording signal SRSA from the optical disk DK on which the code multiplexed encrypted recording signal SRSA is recorded, and extracting the encrypted recorded signal SRS from the detected code multiplexed encrypted recording signal SRSA Only the reproducing circuit 21 to be operated. The playback device specific code memory 22, the descrambling function generator 23, and the descrambling circuit 24 are arranged on a descrambling board B inserted into an expansion slot in the computer CO, and a modified inverse from the IC card C is provided there. The encrypted recording signal SRS is decrypted and reproduced by inputting the scramble function signal SRFX by a predetermined method. The reproduced recording signal SR is output to a computer main body M including a CPU and the like. Since the operation of each member on the reverse scramble board B is the same as that of the first embodiment, the detailed description is omitted.

In the third embodiment, since only the encrypted recording signal SR is output from the regenerator S6, it is not illegally copied. Furthermore, the regenerated recording signal SR is stored in the computer CO. It is very difficult to plagiarize because it is given and received only in

As described above, according to the third embodiment, even when the optical disk DK is applied to a CD-ROM for a computer, the same effect as that of the first embodiment can be obtained.

In the third embodiment, instead of the IC card C, a flexible disk (FD) can be used as a recording medium for recording the modified descrambling function signal SRFX. In this case, the modified descrambling function signal SRFX is read by the FD drive device of the computer CO and directly output to the descrambling function generator 23 on the scramble board B. (V) Fourth Embodiment Next, a fourth embodiment in which the optical disk DK in the second embodiment is applied to a CD-ROM will be described with reference to FIG.

In the fourth embodiment, the information recording apparatus and the disk registration device are the same as those in the second embodiment, and thus detailed description thereof is omitted. However, in the present embodiment, as in the third embodiment, digital data for a computer is encrypted and recorded as a recording signal SR, not a recording signal including video information and music information.

Next, a playback device and a computer according to the fourth embodiment will be described. In the following description, members similar to those in the second embodiment are denoted by the same member numbers, and detailed description thereof is omitted. As shown in FIG. 7, the regenerator S7 in the fourth embodiment is digital data. A pickup 20 for detecting the code multiplexed encrypted recording signal SRSA from the optical disk DK 'on which the code multiplexed encrypted recording signal SRSA is recorded, and an encrypted recording signal SRS from the detected code multiplexed encrypted recording signal SRSA. The reproducing circuit 21 for extraction and the recording head 31 for reading the modified descrambling function signal SRFX recorded in the magnetic recording band T of the optical disk DK ′ are constituted. The playback device specific code memory 22, the descrambling function generator 23, and the descrambling circuit 24 are arranged on the descrambling board B inserted in the expansion slot in the computer CO and recorded as in the third embodiment. By inputting the modified descrambling function signal SRFX from the head 31, the encrypted recording signal SRS is decrypted and reproduced. The reproduced recording signal SR is output to a computer main body M including a CPU and the like. Since the operation of each member on the reverse scramble board B is the same as that of the second embodiment, detailed description thereof is omitted.

In the fourth embodiment, since only the encrypted recording signal SR and the modified descramble function signal SRFX are output from the player S6, they are not illegally copied, and the reproduced recording signal is further reproduced. Since SR is exchanged only within the computer CO, it is very difficult to steal.

As described above, according to the fourth embodiment, even when the optical disc DK ′ is applied to a CD-ROM for a computer, the same effect as that of the second embodiment can be obtained.

In each of the above embodiments, when one consumer owns a plurality of regenerators, the regenerator specifying codes of the regenerators owned by the consumer are all unified to be the same. The device identification code can be used as a consumer identification code.

1 is a schematic configuration block diagram of an information recording apparatus according to a first embodiment. It is a general | schematic block diagram of the IC card issuing machine which concerns on 1st Embodiment. 1 is a schematic configuration block diagram of a regenerator according to a first embodiment. It is a general | schematic block diagram of the disk registration machine which concerns on 2nd Embodiment. It is a schematic block diagram of a regenerator according to the second embodiment. It is a general | schematic block diagram of the reproducing | regenerating apparatus and computer which concern on 3rd Embodiment. It is a general | schematic block diagram of the reproducing | regenerating apparatus and computer which concern on 4th Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Video / audio signal source 2 ... Disc identification code generator 3 ... Scramble function generator 4 ... Scrambler 5 ... Formatter 6 ... Recording device 7 ... Inverse scramble function generator 8 ... Transmission device 10 ... Disc identification code reader 11 ... Memory device 12 ... Keyboard 13 ... Playback device specific code file 14 ... Collator 15 ... Modified inverse scramble function generator 16 ... Modified inverse scramble function recorder 20 ... Pickup 21 ... Playback circuit 22 ... Playback device specific code memory 23 ... Reverse Scramble function generator 24 ... Reverse scramble circuit 25 ... Monitor receiver 30 ... Recording head 31 ... Read head B ... Reverse scramble board C ... IC card CO ... Computer DK, DK '... Optical disk S1 ... Information recording device S2 ... IC card issue Machines S3, S5, S6, S7 ... Reproducing machine S4 ... Disk registration machine SR ... Recording signal SRS ... encrypted recording signal SRSA ... code multiplexed encrypted recording signal SI ... disc identification code signal SF ... scramble function signal SIF ... code multiplexed inverse scramble function signal SRF ... reverse scramble function signal ST ... reproducing device specific code signal SRFX ... Modified inverse scramble function signal SRF ... Descramble function signal T ... Magnetic recording band M ... Computer main body

Claims (10)

An encryption function for encrypting a recording signal corresponding to recording information to be recorded on the recording medium in correspondence with an identification code for identifying a recording medium set in advance or based on the identification code An encryption function generating step to generate, an encryption step of encrypting the recording signal using the generated encryption function to generate an encrypted recording signal, and the corresponding identification code together with the encrypted recording signal A recording step for recording on the recording medium, a decryption function generation step for generating a decryption function for decrypting the encrypted recording signal based on the encryption function, and the decryption function and the corresponding identification code. An information recording method comprising: a transmission step of transmitting to the outside as a set. A decryption function inputted from the outside for decrypting an encrypted recording signal obtained by encrypting a recording signal corresponding to the recording information to be recorded on the first recording medium by an encryption function, and a reproduction that should permit the reproduction of the recording information A modified decryption function generating step for generating a modified decryption function based on a playback device identification code input from the outside for identifying a device, and a modified decryption function recording step for recording the modified decryption function in an external second recording medium And a function recording method. An externally input decryption function for decrypting an encrypted recording signal obtained by encrypting a recording signal corresponding to the recording information to be recorded on the recording medium by an encryption function, and a playback device to permit reproduction of the recorded information A modified decryption function generating step for generating a modified decryption function based on a playback device identification code input from the outside for specifying, and a modified decryption function recording step for recording the modified decryption function on the recording medium. A function recording method characterized by the above. A detection step of detecting the encrypted recording signal from a first recording medium in which the encrypted recording signal obtained by encrypting the recording signal corresponding to the recording information by the encryption function is recorded, and for decrypting the encrypted recording signal The modified decryption function is read out from the second recording medium in which the modified decryption function generated by using the decryption function and the playback device identification code for identifying the playback device that is allowed to reproduce the recorded information is recorded in advance. A decryption function generating step for generating the decryption function based on the modified decryption function and the playback device specific code stored in advance, and decrypting the encrypted recording signal detected using the decryption function, And a decoding step for outputting a signal. A detection step of detecting an encrypted recording signal from a recording medium in which an encrypted recording signal obtained by encrypting a recording signal corresponding to the record information by an encryption function is recorded; and a decryption for decrypting the encrypted recording signal The modified decryption function is read from the recording medium in which the modified decryption function generated using the function and the playback device identification code for identifying the playback device that is permitted to reproduce the recorded information is recorded in advance, and the modified A decryption function generating step for generating the decryption function based on the decryption function and the previously stored playback device identification code; decrypting the encrypted recording signal detected using the decryption function; and outputting the recording signal An information reproducing method comprising: a decrypting step. An encryption function for encrypting a recording signal corresponding to recording information to be recorded on the recording medium in correspondence with an identification code for identifying a recording medium set in advance or based on the identification code An encryption function generating means for generating, an encryption means for encrypting the recording signal using the encryption function, and outputting an encrypted recording signal; and the identification code corresponding to the encrypted recording signal as the recording medium Recording means for recording, decryption function generating means for generating a decryption function for decrypting the encrypted recording signal based on the encryption function, and transmission means for transmitting the decryption function and the identification code to the outside And an information recording apparatus. Detection means for detecting the identification code from the recording medium in which an identification code for identifying the recording medium is recorded in advance, and a recording signal corresponding to the recording information to be recorded on the recording medium is encrypted by an encryption function Storage means for storing the decryption function inputted from the outside for decrypting the encrypted recording signal and the identification code inputted from the outside, and the decryption read from the storage means based on the detected identification code A modified decryption function generating means for generating a modified decryption function based on a function and a playback device specifying code for specifying a playback device that should permit playback of the recorded information input from outside, A function recording apparatus comprising: a modified decryption function recording means for recording in the recording apparatus. Detection means for detecting the identification code from the recording medium in which an identification code for identifying the recording medium is recorded in advance, and a recording signal corresponding to the recording information to be recorded on the recording medium is encrypted by an encryption function Storage means for storing the decryption function inputted from the outside for decrypting the encrypted recording signal and the identification code inputted from the outside, and the decryption read from the storage means based on the detected identification code A modified decryption function generating means for generating a modified decryption function based on a function and a playback device specifying code for specifying a playback device that should permit the playback of the recorded information input from outside; A function recording apparatus comprising: a modified decryption function recording means for recording on a medium. Detection means for detecting the encrypted recording signal from a recording medium in which the encrypted recording signal obtained by encrypting the recording signal corresponding to the recording information by the encryption function is recorded, and decryption for decrypting the encrypted recording signal The modified decryption function is read from the recording device in which the modified decryption function generated using the function and the playback device specifying code for identifying the playback device that is permitted to reproduce the recorded information is recorded in advance. A decryption function generating means for generating the decryption function based on the function and the pre-stored playback device identification code; and decrypting the encrypted recording signal detected using the decryption function and outputting the recording signal An information reproducing apparatus comprising: a decoding means. Detection means for detecting the encrypted recording signal from a recording medium in which the encrypted recording signal obtained by encrypting the recording signal corresponding to the recording information by the encryption function is recorded, and decryption for decrypting the encrypted recording signal The modified decryption function is read from the recording medium in which the modified decryption function generated using the function and the playback device identification code for identifying the playback device that is permitted to reproduce the recorded information is recorded in advance, and the modified Decryption function generating means for generating the decryption function based on the decryption function and the pre-stored playback device identification code, and decrypting the encrypted recording signal detected using the decryption function, and outputting the recording signal And an information reproducing device comprising:

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