WO2009144802A1 - Information generating equipment and method, information reproduction equipment and method, and recording medium - Google Patents

Information generating equipment and method, information reproduction equipment and method, and recording medium Download PDF

Info

Publication number
WO2009144802A1
WO2009144802A1 PCT/JP2008/059930 JP2008059930W WO2009144802A1 WO 2009144802 A1 WO2009144802 A1 WO 2009144802A1 JP 2008059930 W JP2008059930 W JP 2008059930W WO 2009144802 A1 WO2009144802 A1 WO 2009144802A1
Authority
WO
WIPO (PCT)
Prior art keywords
data
user data
information
auxiliary data
auxiliary
Prior art date
Application number
PCT/JP2008/059930
Other languages
French (fr)
Japanese (ja)
Inventor
和幸 吉田
Original Assignee
パイオニア株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by パイオニア株式会社 filed Critical パイオニア株式会社
Priority to PCT/JP2008/059930 priority Critical patent/WO2009144802A1/en
Publication of WO2009144802A1 publication Critical patent/WO2009144802A1/en

Links

Images

Classifications

    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
    • G11B20/10—Digital recording or reproducing
    • G11B20/18—Error detection or correction; Testing, e.g. of drop-outs
    • G11B20/1833—Error detection or correction; Testing, e.g. of drop-outs by adding special lists or symbols to the coded information
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
    • G11B20/00086—Circuits for prevention of unauthorised reproduction or copying, e.g. piracy
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
    • G11B20/00086—Circuits for prevention of unauthorised reproduction or copying, e.g. piracy
    • G11B20/0021—Circuits for prevention of unauthorised reproduction or copying, e.g. piracy involving encryption or decryption of contents recorded on or reproduced from a record carrier
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
    • G11B20/00086—Circuits for prevention of unauthorised reproduction or copying, e.g. piracy
    • G11B20/0021—Circuits for prevention of unauthorised reproduction or copying, e.g. piracy involving encryption or decryption of contents recorded on or reproduced from a record carrier
    • G11B20/00217—Circuits for prevention of unauthorised reproduction or copying, e.g. piracy involving encryption or decryption of contents recorded on or reproduced from a record carrier the cryptographic key used for encryption and/or decryption of contents recorded on or reproduced from the record carrier being read from a specific source
    • G11B20/00253—Circuits for prevention of unauthorised reproduction or copying, e.g. piracy involving encryption or decryption of contents recorded on or reproduced from a record carrier the cryptographic key used for encryption and/or decryption of contents recorded on or reproduced from the record carrier being read from a specific source wherein the key is stored on the record carrier
    • G11B20/00282—Circuits for prevention of unauthorised reproduction or copying, e.g. piracy involving encryption or decryption of contents recorded on or reproduced from a record carrier the cryptographic key used for encryption and/or decryption of contents recorded on or reproduced from the record carrier being read from a specific source wherein the key is stored on the record carrier the key being stored in the content area, e.g. program area, data area or user area

Definitions

  • the present invention relates to an information generation apparatus and method using an error correction code, an information reproduction apparatus and method, and a technical field of a recording medium.
  • Patent Document 1 discloses a technique in which identification data for identifying whether user data is illegally copied is embedded as an intentional error, and information indicating the position of the error is encrypted and recorded separately.
  • Patent Document 2 discloses a technique for detecting a position where an error is embedded by comparing data before and after error correction.
  • the present invention has been made in view of the above-described problems, for example, and an information generation apparatus and method, and an information reproduction apparatus capable of generating information that can reliably reproduce auxiliary data while preventing an increase in the amount of data. And a method and a recording medium.
  • the first information generation apparatus of the present invention replaces a part of user data with auxiliary data that is related to the user data and is used for a purpose different from the user data.
  • An information generation apparatus for generating replacement user data wherein an error correction code is added to the user data to generate encoded data, and the auxiliary data in the encoded data is added to the auxiliary data.
  • replacement user data is generated by replacing part of user data with auxiliary data.
  • the “user data” is data that is the basis of generated replacement user data, and examples thereof include electronic files, audio data, and image data.
  • “Auxiliary data” is auxiliary data related to user data, and is used for purposes different from user data. As an example of auxiliary data, data indicating user data attributes, file name, management number, etc., data indicating the division position of divided user data, and whether or not user data is illegally copied data Data and the like.
  • the auxiliary data is typically data with a very small amount of information compared to user data.
  • the generated replacement user data is modulated by a predetermined method, for example, and then recorded on a recording medium such as a holographic memory or an optical disk, or transmitted using a network such as the Internet.
  • the error correction code is added to the user data by the encoding means, and the encoded data is generated. Subsequently, position information indicating the position of the data to be replaced with the auxiliary data in the encoded data is generated by the position information generating means.
  • the position information is generated based on user data. That is, the position information is generated by a predetermined process using user data. If the position information is information uniquely obtained from user data such as a hash value generated by a hash function, for example, the position information may not be information directly indicating the position of the data. In such a case, for example, the position of data to be replaced is indicated by setting in advance a rule that associates the value of the position information with the position of the data to be replaced.
  • auxiliary data is replaced after encoding, it is embedded in the user data as an intentional error.
  • the replacement user data generated as described above is decoded by correcting an error with an error correction code when reproduced as user data.
  • the replaced auxiliary data since the replaced auxiliary data is handled as an error in the user data, it does not remain in the decoded user data.
  • the position information can be generated again from the user data. Therefore, auxiliary data can be easily and reliably extracted from replacement user data before decoding based on position information.
  • the auxiliary data is replaced as a part of the user data, the size of the entire data can be reduced as compared with the case where the auxiliary data is handled as another data. Also, the position information can be generated from the user data, so it is not necessary to keep it. Therefore, it is possible to effectively prevent an increase in data amount.
  • auxiliary data can be reliably reproduced as long as even user data can be reproduced.
  • the position information can be generated from the user data, so that it is possible to reliably extract only the auxiliary data.
  • the first information generating apparatus of the present invention it is possible to generate information that can reliably reproduce auxiliary data while avoiding various practical inconveniences.
  • the encoded data is divided into blocks for each predetermined number of continuous data, and the replacement means converts the encoded data for each block. Replace with one auxiliary data.
  • the encoded data is divided into blocks for each predetermined number of continuous data.
  • “division” does not mean that encoded data is handled as a plurality of data, but means that there is a delimiter in the data.
  • the auxiliary data is replaced with one of the encoded data for each block. That is, in each block in the encoded data, one piece of data constituting the block is replaced with auxiliary data.
  • the auxiliary data is preferably distributed in the replacement user data. Therefore, it is possible to effectively prevent an error from occurring in most or all of the auxiliary data and the auxiliary data from being reproduced.
  • the above effect can be obtained by replacing the auxiliary data with a predetermined number (ie, 2 or more) of encoded data for each block. can get. That is, for each block, two auxiliary data may be replaced with two encoded data, or three auxiliary data may be replaced with three encoded data.
  • the information processing device further includes auxiliary encoding means for adding an error correction code to the auxiliary data, and the replacement means converts a part of the encoded data to the error.
  • Substitution user data is generated by substituting the auxiliary data to which the correction code is added.
  • the error correction code is also added to the auxiliary data by the auxiliary encoding means. That is, auxiliary data is encoded in the same manner as user data. Note that the encoding methods of user data and auxiliary data may be the same or different.
  • auxiliary data Since the auxiliary data is encoded, even if an error occurs in the auxiliary data, it can be decoded into correct data by the error correction code. Therefore, in this aspect, auxiliary data can be reproduced more reliably.
  • the information generating device further comprises: encryption means for generating user data encrypted by encrypting the user data with the auxiliary data;
  • the error correction code is added to the encrypted user data to generate encoded data, and the position information generating means generates the position information based on the encrypted user data .
  • the user data is encrypted by the encryption means before being encoded by the encoding means.
  • auxiliary data is used for encrypting user data. That is, the auxiliary data can be considered as key information for decrypting the user data.
  • the auxiliary data may include data other than data for encrypting user data.
  • the auxiliary data is replaced with a part of the replacement user data, and thus does not increase the data. Moreover, it can extract reliably by the positional information produced
  • the security for the user data can be improved. Further, since the position information cannot be generated correctly without the key information, the security can be similarly improved.
  • the position information generating means generates the position information based on key information in addition to the user data.
  • the position information means is generated based on the key information in addition to the user data.
  • the position information is generated as temporary position information based on user data and then encrypted based on key information.
  • it may be generated based on user data encrypted with the key information. It is also possible to generate directly from user data and key information using HMAC (Keyed-Hashingashfor Message Authentication Code).
  • HMAC Keyed-Hashingashfor Message Authentication Code
  • the position information is generated in an encrypted state, key information is required when correctly generating the position information.
  • key information is required when there is no key information.
  • the information generating device further includes auxiliary data changing means for changing the auxiliary data using the position information.
  • the auxiliary data is changed using the position information before being replaced with the encoded data.
  • the “change” here is a reversible change, and the changed auxiliary data can be returned to the original auxiliary data using the position information again. That is, the change here can also be called auxiliary data encryption using position information as key information.
  • auxiliary data can be improved by changing the auxiliary data using location information. Further, since the position information can be generated based on the user data, it does not have to be held separately from the user data. Therefore, it is possible to prevent the amount of information from increasing unnecessarily.
  • the second information generation apparatus of the present invention replaces a part of user data with auxiliary data that is related to the user data and is used for a purpose different from the user data.
  • An information generation device for generating replacement user data wherein an error correction code is added to the user data to generate encoded data, and the auxiliary data is changed to change auxiliary data
  • replacement user data is generated by replacing part of user data with auxiliary data.
  • the “user data” is data that is the basis of generated replacement user data, and examples thereof include electronic files, audio data, and image data.
  • “Auxiliary data” is auxiliary data related to user data, and is used for purposes different from user data. As an example of auxiliary data, data indicating user data attributes, file name, management number, etc., data indicating the division position of divided user data, and whether or not user data is illegally copied data Data and the like.
  • the auxiliary data is typically data with a very small amount of information compared to user data.
  • the generated replacement user data is modulated by a predetermined method, for example, and then recorded on a recording medium such as a holographic memory or an optical disk, or transmitted using a network such as the Internet.
  • the error correction code is added to the user data by the encoding means to generate encoded data.
  • change information for changing auxiliary data to change auxiliary data is generated by the change information generating means.
  • the “change” here is a reversible change, and the changed auxiliary data can be returned to the original auxiliary data using the change information again.
  • the change information is generated based on user data. That is, the change information is generated by a predetermined process using user data.
  • the change information may be information uniquely obtained from user data such as a hash value generated by a hash function.
  • the change auxiliary data is generated, for example, by encrypting the auxiliary data using the change information as key information. In other words, the security for the auxiliary data can be improved by changing the auxiliary data using the change information.
  • the change auxiliary data When the change auxiliary data is generated, a part of the encoded data is replaced with the change auxiliary data by the replacement means, and replacement user data is generated. Since the change auxiliary data is replaced after encoding, it is embedded in the user data as an intentional error.
  • the replacement user data generated as described above is decoded by correcting an error with an error correction code when reproduced as user data.
  • the changed change auxiliary data is handled as an error in the user data, and therefore does not remain in the decoded user data.
  • it is possible to suitably extract the change auxiliary data by separately storing position information indicating the position of the replaced change auxiliary data, or by previously setting the position of the change auxiliary data to be replaced. It is.
  • change auxiliary data can be extracted by comparing user data before and after error correction, that is, replacement user data and decoded user data.
  • the extracted change auxiliary data can be changed back to the original auxiliary data based on the change information. Since the change information can be generated from user data, it does not have to be retained. It can be prevented that the auxiliary data cannot be restored due to an error in the change information. That is, auxiliary data can be reliably reproduced as long as even user data can be reproduced.
  • auxiliary data is also replaced as a part of the user data, the size of the entire data can be reduced as compared with the case where the auxiliary data is handled as another data.
  • the second information generating apparatus of the present invention information capable of reliably reproducing auxiliary data can be generated while realizing high security.
  • replacement user data generated by the above-described first information generating apparatus of the present invention is recorded in order to solve the above-described problems.
  • the replacement user data generated by the first information generation apparatus of the present invention described above is recorded, it is ensured that an error will occur when the recorded data is reproduced.
  • auxiliary data in the user data can be extracted.
  • auxiliary data and position information need not be recorded separately from user data, it is possible to secure a sufficient area for recording user data.
  • the replacement user data generated by the above-described second information generating apparatus of the present invention is recorded, high security is ensured when the recorded data is reproduced. While realizing, auxiliary data in user data can be reliably extracted. In addition, since auxiliary data and position information need not be recorded separately from user data, it is possible to secure a sufficient area for recording user data.
  • a first information reproducing apparatus of the present invention is an information reproducing apparatus for reproducing replacement user data generated by the above-described first information generating apparatus of the present invention, wherein the replacement user data Decoding means for decoding the user data into the user data using the error correction code, second position information generating means for generating the position information based on the decoded user data, and the second position information generation Extraction means for extracting the auxiliary data from the replacement user data based on the position information generated by the means.
  • the replacement user data generated by the above-described first information generating apparatus of the present invention is reproduced.
  • the replacement user data is first decoded by the decoding means using the error correction code.
  • the auxiliary data which is an intentionally embedded error is returned to the user data before replacement. Also, errors that occur during recording are corrected in the same manner.
  • position information is generated from the decoded user data by the second position information generating means.
  • the second position information generating means generates position information in the same manner as the position information generating means in the first information generating apparatus of the present invention described above.
  • the position information generating means in the information generating device and the second position information generating means in the information reproducing means may be the same.
  • auxiliary data is extracted from the replacement user data by the extracting means. That is, according to the present invention, auxiliary data can be reliably reproduced as long as user data can be reproduced.
  • the replacement user data is stored in, for example, a memory or the like separately from the user data decoded by the decoding unit, and the extraction unit extracts auxiliary data from the stored replacement user data.
  • the second information reproducing apparatus of the present invention is an information reproducing apparatus for reproducing the replacement user data generated by the above-described second information generating apparatus of the present invention, wherein the replacement user data From the extraction means for extracting the change auxiliary data, the decoding means for decoding the replacement user data into the user data using the error correction code, and the change information based on the decoded user data Second change information generating means to be generated, and re-change means for re-changing the change auxiliary data to the auxiliary data based on the change information generated by the second change information generating means.
  • the replacement user data generated by the above-described second information generating apparatus of the present invention is reproduced.
  • the replacement user data is first decoded by the decoding means using the error correction code.
  • the change auxiliary data which is an intentionally embedded error is returned to the user data before replacement.
  • the extraction means extracts the change auxiliary data using, for example, position information indicating the position of the replaced user data.
  • the position information may be information stored separately from the user data, or may be set in advance before replacing the user data.
  • the change auxiliary data can be extracted by comparing the replacement user data before decryption with the user data after decryption. That is, the change auxiliary data can be extracted by utilizing the fact that the change auxiliary data, which is an intentional error, is corrected by decoding.
  • the replacement user data is stored in, for example, a memory or the like separately from the user data decrypted by the decryption means, and the extraction means compares the stored replacement user data with the decrypted user data.
  • change information for re-changing the change auxiliary data to auxiliary data is generated by the second change information generating means.
  • the second change information generation means generates change information in the same manner as the change information generation means in the second information generation apparatus of the present invention described above.
  • the change information generating means in the information generating device and the second change information generating means in the information reproducing means may be the same.
  • the change auxiliary data is changed again to auxiliary data by the re-change means. That is, according to the present invention, auxiliary data can be reliably reproduced as long as user data can be reproduced.
  • the change auxiliary data is re-changed into auxiliary data, for example, by performing an arithmetic process or the like reverse to that when changing the auxiliary data to change auxiliary data.
  • a first information generation method of the present invention replaces a part of user data with auxiliary data that is related to the user data and is used for a different purpose from the user data.
  • An information generation method for generating replacement user data wherein an error correction code is added to the user data to generate encoded data, and the auxiliary data in the encoded data is added to the auxiliary data.
  • a replacement step of generating replacement user data A position information generation step for generating position information indicating the position of data to be replaced based on the user data; and a part of the encoded data is replaced with the auxiliary data based on the position information;
  • the auxiliary data is replaced with a part of the encoded data, and the position information indicating the position of the replaced data is generated based on the user data.
  • the first information generation apparatus it is possible to generate information that can reliably reproduce the auxiliary data while avoiding various practical inconveniences.
  • the second information generation method of the present invention replaces part of user data with auxiliary data that is related to the user data and is used for a different purpose from the user data.
  • An information generation method for generating replacement user data wherein an error correction code is added to the user data to generate encoded data, and the auxiliary data is changed to change auxiliary data
  • a replacement step of generating the replacement user data by replacing the portion with the change auxiliary data is a different purpose from the user data.
  • the auxiliary data is converted into the change auxiliary data based on the change information generated based on the user data, so that it is the same as the second information generation device described above.
  • a first information reproduction method of the present invention is an information reproduction method of reproducing replacement user data generated by the above-described first information generation method of the present invention, wherein the replacement user data Is decoded into the user data using the error correction code, a second position information generation step is generated based on the decoded user data, and the second position information generation is performed.
  • the user data and the auxiliary data are reliably obtained from the replacement user data as in the first information reproducing apparatus described above. Can play.
  • a second information reproduction method of the present invention is an information reproduction method of reproducing replacement user data generated by the above-described second information generation method of the present invention, wherein the replacement user data From the extraction step of extracting the change auxiliary data, the decoding step of decoding the replacement user data into the user data using the error correction code, and the change information based on the decoded user data A second change information generation step that is generated, and a re-change step that re-changes the change auxiliary data into the auxiliary data based on the change information generated in the second change information generation step.
  • the change information is generated based on the user data, so that the user data and the auxiliary data are reliably obtained from the replacement user data as in the second information reproducing apparatus described above. Can play.
  • FIG. 1 is a block diagram showing the configuration of the information generating apparatus and the information reproducing apparatus according to the first embodiment
  • FIG. 2 shows a modification of the information generating apparatus and the information reproducing apparatus according to the first embodiment. It is a block diagram.
  • the information generation apparatus 100 includes an encoding unit 110, a position information generation unit 120, a second encoding unit 130, a replacement unit 140, a modulation unit 150, and a writing unit 160. And is configured.
  • the encoding unit 110 is an example of the “encoding unit” of the present invention, and adds an error correction code to input user data (for example, data to be recorded such as a video file, a music file, a document file). To do.
  • the position information generation unit 120 is an example of the “position information generation unit” of the present invention, and generates position information indicating the position of data to be replaced in the replacement unit 140 described later from the input user data.
  • the position information is information that is uniquely obtained from the user information.
  • the second encoding unit 130 is an example of the “auxiliary encoding unit” of the present invention, and adds an error correction code to the input auxiliary data.
  • the auxiliary data is auxiliary data related to the user data, and is used for a purpose different from the user data.
  • auxiliary data data indicating user data attributes, file name, management number, etc., data indicating the division position of divided user data, and whether or not user data is illegally copied data Data and the like.
  • the encoding unit 110 and the second encoding unit 130 may be configured by the same arithmetic circuit or the like.
  • the replacement unit 140 is an example of the “replacement unit” of the present invention, and replaces part of the user data encoded by the encoding unit 110 with auxiliary data encoded by the second encoding unit 130. At this time, the position of the user data to be replaced is based on the position information generated by the position information generation unit 120.
  • the modulation unit 150 modulates the user data replaced by the replacement unit 140 into data of an appropriate system for recording.
  • information is recorded in the holographic memory 300 as in the present embodiment, for example, (2, 4) modulation in which 2 bits of data are indicated by 4 pixels and 6 bits of data are indicated by 9 pixels. (6, 9) modulation or the like is used.
  • the writing unit 160 includes, for example, a light source, a lens, and the like, condenses the laser light emitted from the light source with the lens, irradiates the holographic memory 300, and stores user data as interference fringes.
  • the information generating apparatus and the information reproducing apparatus can be used not only for recording information but also for exchanging information by communication, for example.
  • user data modulated for communication in the modulation unit 150 is transmitted as an electrical signal via a communication cable 400 as shown in the figure, for example.
  • the information generation device and the information reproduction device perform information position specification, management information processing, and the like using a synchronization signal.
  • FIG. 3 is a flowchart showing an operation flow of the information generating apparatus according to the first embodiment.
  • FIG. 4 is a conceptual diagram illustrating a method for generating position information
  • FIGS. 5 and 6 are conceptual diagrams illustrating a method for replacing user data with auxiliary data.
  • step S11 when the information generating apparatus 100 according to the first embodiment operates, first, user data is input to the encoding unit 110.
  • the encoding unit 110 adds an error correction code to the input user data (step S11).
  • error correction codes (C1 to C4) for user data are typically added to the last part of user data (U1 to U8).
  • the arrangement of each data may be rearranged by interleaving or the like.
  • auxiliary data is input to the second encoding unit 130.
  • the second encoding unit 130 adds an error correction code to the auxiliary data (step S12).
  • the auxiliary data also has an error correction capability like the user data.
  • the error correction code (E1) for the auxiliary data is typically added to the last part of the auxiliary data (A1 and A2).
  • the arrangement of each data may be rearranged by interleaving or the like.
  • the position information generation unit 120 generates position information indicating the position of data to be replaced when a part of the user data is replaced with auxiliary data based on the input user data (step S13).
  • a hash value generated by a hash function can be used.
  • SHA-1 Secure Hash Algorithm 1
  • an arbitrary length input value that is, user data
  • a 160-bit output value that is, position information
  • the position information may not be information that directly indicates the position of the data as long as it is information uniquely obtained from the user data, such as a hash value. In such a case, for example, the position of the data to be replaced is indicated by setting in advance a rule that associates the value of the position information with the position of the data to be replaced.
  • the replacement unit 140 replaces part of the user data with auxiliary data (step S14).
  • the replacement unit 140 replaces user data with auxiliary data based on the position information generated by the position information generation unit 120. Since user data is replaced with auxiliary data after an error correction code is added, the replaced auxiliary data is treated as an intentional error.
  • position information such as 7, 2, 5, 6, 8,... Has been generated from the user data (U1 to U8) by the position information generation unit 120.
  • the user data is divided into three blocks from the first block to the third block every four data, and position numbers 0 to 3 are assigned to the data in each block.
  • the number of blocks in the user data is the number of auxiliary data to be replaced (that is, three of A1, A2, and E1 here). ) Or more.
  • auxiliary data when the amount of auxiliary data is large, for example, when the number of auxiliary data values is larger than the number of output values of the hash function output as position information, the value for indicating the position information is insufficient. End up.
  • Such a case can be dealt with by generating a value obtained by further inputting the output of the hash function into the hash function (that is, a hash value of the hash value).
  • the replacement unit 140 stores a rule that the user data of the position indicated by the remainder obtained by dividing each value of the position information by the block length (in this case, “4”) and the auxiliary data are replaced.
  • the position information corresponds to the first block, the second block, and the third block from the top value, and the fourth and subsequent values are not used here. However, the fourth and subsequent values may be used.
  • the replacement method described above is merely an example.
  • the rule of replacing auxiliary data according to the remainder obtained by dividing each value of the position information by “4” that is the block length if the remainder is 0 or 3, replacement in the corresponding block is performed. Without replacement, the replacement of position 0 and position 2 is performed when the remainder is 2, and the replacement is performed using the rule of replacing position 1 when the remainder is 1.
  • the first block is not replaced because the remainder of dividing the first value “7” of the position information by 4 becomes “3”.
  • the remainder obtained by dividing “2”, which is the second value of the position information, by 4 is “2”, so that the auxiliary data A1 and A2 are the user data U5 and the position of the position 0 of the second block. 2 is replaced with the user data U7.
  • the remainder of dividing the third value “5” of the position information by 4 is “1”, so the error correction code E1 added to the auxiliary data is the position 1 of the third block. Replaced with error correction code C2.
  • auxiliary data in the block can be freely changed, for example, it has been found that errors such as scratches and noise are likely to occur at a specific location of the recording medium and a specific timing of the communication path. It is possible not to replace the symbols in the corresponding block with auxiliary data, or to reduce the number of symbols to be replaced. Thereby, possibility that auxiliary data will be extracted accidentally can be reduced.
  • the replacement method is not particularly limited as long as it uses position information, and it is possible to appropriately exert the effect of the information generation apparatus according to the present embodiment described later. It is also possible to set a plurality of replacement methods in advance and switch the rules at specific timings. This effect will be described in detail in the description of the information reproducing apparatus according to the present embodiment described later.
  • the modulation unit 150 modulates the user data into a method suitable for recording (step S15).
  • the writing unit 160 records the modulated user data in the holographic memory 300 (step S16).
  • position information indicating the position of the replaced auxiliary data is not recorded in the holographic memory 300.
  • it is not necessary to record on another recording medium. Therefore, the size of the data recorded here is the same as the size of the user data to be recorded.
  • the information reproducing apparatus 200 includes a reading unit 210, a demodulating unit 220, a decoding unit 230, a second position information generating unit 240, an extracting unit 250, and a second decoding unit 260. And is configured.
  • the reading unit 210 includes, for example, a light emitting unit, a lens, and a light receiving element.
  • the reading unit 210 detects an image obtained by irradiating the holographic memory 300 with laser light by the light receiving element, and user data is detected from the detected image. Play.
  • the demodulator 220 demodulates the user data modulated by the modulator 150 in the information generation apparatus 100 to the original state. That is, the reverse process of the modulation unit 150 is performed.
  • the decoding unit 230 is an example of the “decoding unit” of the present invention, and corrects an error included in user data using an error correction code added to the user data.
  • the second position information generation unit 240 is an example of the “second position information generation unit” in the present invention, and the information generation apparatus uses the user data decoded by the decoding unit 230 (that is, user data whose error is corrected).
  • the position information is generated in the same manner as the position information generation unit 120 in 100.
  • the position information generation unit 120 can also be used as the second position information generation unit 240.
  • the extraction unit 250 is an example of the “extraction unit” of the present invention, and the second position information generation unit 240 uses user data before decoding (that is, user data in which auxiliary data is included as an intentional error). Auxiliary data is extracted using the generated position information.
  • the second decoding unit 260 corrects an error included in the auxiliary data by using an error correction code added to the extracted auxiliary data.
  • FIG. 7 is a flowchart showing an operation flow of the information reproducing apparatus according to the first embodiment.
  • FIG. 8 is a conceptual diagram illustrating a method for decoding user data and generating position information.
  • FIG. 9 is a conceptual diagram illustrating a method for extracting and decoding auxiliary data.
  • the reading unit 210 first reads out user data recorded in the holographic memory 300 (step S21). Subsequently, the demodulator 220 demodulates the read user data to a state before modulation (step S22).
  • the decoding unit 230 corrects the error included in the user data using the error correction code added to the user data (step S23).
  • the auxiliary data replaced with part of the user data by the replacement unit 140 in the information generating apparatus 100 is corrected as an error. That is, the auxiliary data is user data before replacement.
  • the decrypted user data is output to the outside as a reproduction result and also output to the second position information generation unit 240.
  • the second position information generation unit 240 generates position information using the decoded user data (step S24).
  • user data (D1 to D12) read by the reading unit 210 includes scratches in the holographic memory 300 and noise during recording and reproduction, in addition to auxiliary data that is an intentional error. Etc., some errors are included.
  • the decoding unit 230 decodes the user data including such an error and uses it as user data (U1 to U8) before replacement. Since the user data is the same data as the user data used by the position information generation unit 120 in the information generation apparatus 100, the position information generated in the second position information generation unit 240 is generated in the position information generation unit 120. It becomes the same as the position information. As described above, if the user data can be decoded, the second position information generation unit 240 can generate the same position information again. Therefore, it is not necessary to record the position information generated by the position information generation unit 120 in the holographic memory 300 or another recording medium.
  • the position information generated in the second position information generation unit 240 is output to the extraction unit 250. Further, user data before being decoded by the decoding unit 230 is also output to the extraction unit 250. The extraction unit 250 extracts data from the user data before decoding based on the position information (step S25).
  • the position information generated by the second position information generation unit 240 is the same as the position information generated by the position information generation unit 120 (7, 2, 5, 6, 8, ..)),
  • the auxiliary data can be reliably extracted based on the same rule when the replacement unit 140 performs the replacement.
  • the first block since the remainder obtained by dividing “7”, which is the first value of the position information, by 4 is “3”, user data D4 is extracted from position 3 of the first block. .
  • the remainder obtained by dividing “2”, which is the second value of the position information, by 4 is “2”. Therefore, user data D7 is extracted from position 2 of the second block.
  • the remainder of dividing the third value “5” of the position information by 4 is “1”, so user data D10 is extracted from position 1 of the third block.
  • the second decoding unit corrects the error and decodes the auxiliary data (A1 and A2) before encoding (step S26).
  • the decoded auxiliary data is output to the outside as a reproduction result.
  • the information generating apparatus and the information reproducing apparatus it is possible to reliably reproduce auxiliary data while preventing an increase in information to be recorded.
  • auxiliary data is recorded on a recording medium together with user data as identification data for detecting an illegal disk
  • the illegal disk can be detected. Disappear. Therefore, since the auxiliary data cannot be reproduced, there is a possibility that the reproduction of the user data becomes impossible or a disc that may be an illegal disc must be reproduced.
  • FIG. 10 is a block diagram showing the configuration of the information generating device and the information reproducing device according to the second embodiment.
  • the second embodiment differs from the first embodiment described above in that user data is encrypted, and other configurations and operations are generally the same. Therefore, a different part from 1st Embodiment is demonstrated in detail here, and description is abbreviate
  • the components of the information generation device 100 and the information reproduction device 200 are the same as those in the first embodiment described above, and thus detailed illustration is omitted.
  • the user data encrypted by the encryption unit 510 is input to the information generating apparatus 100 according to the second embodiment. Therefore, it is possible to improve the security of user data.
  • Encryption of user data in the encryption unit 510 is performed using key information.
  • the key information used here is input to the information generating apparatus 100 as auxiliary data. Therefore, in the second embodiment, recording is performed with the key information embedded in the user data as an intentional error. Therefore, it is possible to prevent the data size from increasing in order to record the key information.
  • the information reproducing apparatus 200 reads the user data recorded in the holographic memory 300 and outputs the encrypted user data and key information which is auxiliary data as a reproduction result.
  • the encrypted user data and auxiliary data are input to the third decryption unit 520.
  • the third decryption unit 520 decrypts user data encrypted using the key information that is auxiliary data, and outputs the decrypted user data.
  • the information generating apparatus and the information reproducing apparatus since the security for user data is improved, information can be recorded and reproduced more suitably. Further, as in the first embodiment described above, the auxiliary data can be reliably reproduced while preventing an increase in the amount of data, which is extremely advantageous in practice.
  • FIG. 11 is a block diagram showing the configuration of the information generating device and the information reproducing device according to the third embodiment
  • FIGS. 12 to 14 are block diagrams showing the configuration of the position information generating unit.
  • the third embodiment differs from the first embodiment described above in the configuration and operation of the position information generation unit, and the other configurations and operations are generally the same. Therefore, a different part from 1st Embodiment is demonstrated in detail here, and description is abbreviate
  • the same reference numerals are assigned to the same constituent elements as those of the information generating apparatus and the information reproducing apparatus according to the first embodiment described above.
  • key information for encrypting position information is input to the information generating apparatus 100 according to the third embodiment.
  • the key information is input to the position information generation unit 120 as shown in the figure.
  • the position information generation unit 120 includes, for example, a generation unit 121 and a position information encryption unit 122.
  • the generation unit 121 generates position information based on the input user data and outputs the position information to the position information encryption unit 122.
  • the position information encryption unit encrypts the generated position information using the key information, and outputs the encrypted position information as encrypted position information.
  • the location information cannot be generated without the key information, so that the security of the location information can be improved. That is, it is possible to effectively prevent the auxiliary data from being illegally reproduced.
  • the position information generation unit 120 may include a user data encryption unit 123 and a generation unit 121.
  • user data and key information are input to the user data encryption unit 123, and the user data is encrypted.
  • the generation unit 121 generates location information using the encrypted user data.
  • the configuration here is relatively close to that of the second embodiment described above.
  • the location information is not directly encrypted, but the original user data is encrypted. For this reason, it is possible to improve the security of position information as compared with the case where position information is generated using unencrypted user data.
  • the position information generation unit 120 may be configured to include an HMAC processing unit 124.
  • HMAC processing unit 124 user data and key information are input to the HMAC processing unit 124, and position information (hash value) output from the HMAC processing unit 124 is output.
  • the information reproducing apparatus 200 receives key information when reproducing data.
  • the key information may be recorded in the holographic memory 300 or may be recorded on another recording medium.
  • the key information is input to the second position information generation unit 240, and the encrypted position information is output from the second position information generation unit 240 to the extraction unit 250.
  • the second position information generation unit 240 can have a configuration as shown in FIGS.
  • the information generating apparatus and the information reproducing apparatus since the security for the position information is improved, it is possible to perform recording and reproduction while reliably protecting the auxiliary data. it can. Further, as in the first embodiment described above, the auxiliary data can be reliably reproduced while preventing an increase in the amount of data, which is extremely advantageous in practice.
  • FIG. 15 is a conceptual diagram showing a method for generating position information and replacing auxiliary data in the information generating apparatus according to the fourth embodiment
  • FIG. 16 is an auxiliary diagram in the information reproducing apparatus according to the fourth embodiment. It is a conceptual diagram which shows the reproducing method of data. Note that the fourth embodiment differs from the first embodiment described above in that auxiliary data is changed, and other configurations and operations are generally the same. Therefore, a different part from 1st Embodiment is demonstrated in detail here, and description is abbreviate
  • the auxiliary data is changed using the position information before being replaced with part of the user data in the replacement unit 140. That is, the position information has a role of changing the value of the auxiliary data in addition to the role of indicating the position where the auxiliary data is replaced.
  • auxiliary data (A1, A2, and E1) to which an error correction code is added is subjected to arithmetic processing together with positional information 7, 2, 5, 6, 8,. Is changed to It is assumed that the arithmetic processing here (that is, “+” shown in the figure) is an XOR operation.
  • the auxiliary data A1 is set to A1 ′ by performing an XOR operation with the leading value “7” of the position information.
  • the auxiliary data A2 is set to A2 'by performing an XOR operation with the second value "2" of the position information.
  • the error correction code E1 added to the auxiliary data is set to E1 ′ by performing an XOR operation with the third value “5” of the position information.
  • the auxiliary data (A1 ′, A2 ′ and E1 ′) changed by the position information is replaced with a part of the user data by the replacement unit 140 as in the above-described embodiments.
  • the extracted auxiliary data (D4, D6 and D10) are changed based on the position information. Therefore, here, the extracted auxiliary data is re-changed based on the position information. For example, when the auxiliary data is changed by the XOR operation processing as described above, the XOR operation processing is performed again using the position information, thereby canceling the effect of the XOR operation processing, and the auxiliary data is restored to the original value (A1 , A2 and E1). It should be noted that arithmetic processing other than XOR arithmetic processing can be used as long as the arithmetic processing can reversibly change auxiliary data using position information.
  • the security of the auxiliary data is improved by changing the auxiliary data according to the position information. Recording and reproduction can be performed while ensuring protection. Further, as in the first embodiment described above, the auxiliary data can be reliably reproduced while preventing an increase in the amount of data, which is extremely advantageous in practice.
  • the fifth embodiment is different from the first embodiment described above in that change information is used instead of position information, and other configurations and operations are substantially the same. Therefore, a different part from 1st Embodiment is demonstrated in detail here, and description is abbreviate
  • FIG. 17 is a block diagram showing the configuration of the information generating apparatus and the information reproducing apparatus according to the fifth embodiment
  • FIG. 18 shows a modification of the information generating apparatus and the information reproducing apparatus according to the fifth embodiment. It is a block diagram.
  • the information generation apparatus 100 includes an encoding unit 110, a second encoding unit 130, a replacement unit 140, a modulation unit 150, a writing unit 160, and a change information generation unit 170. And a changing unit 180.
  • the encoding unit 110 is an example of the “encoding unit” of the present invention, and adds an error correction code to input user data (for example, data to be recorded such as a video file, a music file, a document file). To do.
  • the second encoding unit 130 is an example of the “auxiliary encoding unit” of the present invention, and adds an error correction code to the input auxiliary data.
  • the auxiliary data is auxiliary data related to the user data, and is used for a purpose different from the user data.
  • auxiliary data data indicating user data attributes, file name, management number, etc., data indicating the division position of divided user data, and whether or not user data is illegally copied data Data and the like.
  • the encoding unit 110 and the second encoding unit 130 may be configured by the same arithmetic circuit or the like.
  • the change information generation unit 170 is an example of the “change information generation unit” of the present invention, and generates change information for changing auxiliary data based on the input user information.
  • the change information is information that is uniquely obtained from the user information.
  • the changing unit 180 is an example of the “auxiliary data changing unit” of the present invention, and changes the encoded auxiliary data using the change information generated by the change information generating unit 170.
  • the change of the auxiliary data is performed, for example, by an arithmetic process using auxiliary data and change information.
  • the replacement unit 140 is an example of the “replacement unit” in the present invention, and replaces part of the user data encoded by the encoding unit 110 with auxiliary data changed by the changing unit 180.
  • the modulation unit 150 modulates the user data replaced by the replacement unit 140 into data of an appropriate system for recording.
  • information is recorded in the holographic memory 300 as in the present embodiment, for example, (2, 4) modulation in which 2 bits of data are indicated by 4 pixels and 6 bits of data are indicated by 9 pixels. (6, 9) modulation or the like is used.
  • the writing unit 160 includes, for example, a light source, a lens, and the like, condenses the laser light emitted from the light source with the lens, irradiates the holographic memory 300, and stores user data as interference fringes.
  • the information generating apparatus and the information reproducing apparatus can be used not only for recording the information described above but also for exchanging information by communication, for example.
  • user data modulated for communication in the modulation unit 150 is transmitted as an electrical signal via a communication cable 400 as shown in the figure, for example.
  • the information generation device and the information reproduction device perform information position specification, management information processing, and the like using a synchronization signal.
  • FIG. 19 is a flowchart showing an operation flow of the information generating apparatus according to the fifth embodiment.
  • FIG. 20 is a conceptual diagram illustrating a method for generating change information
  • FIG. 21 is a conceptual diagram illustrating a method for changing auxiliary data using the change information.
  • user data is first input to the encoding unit 110 when the information generating apparatus 100 according to the fifth embodiment operates.
  • the encoding unit 110 adds an error correction code to the input user data (step S31).
  • error correction codes (C1 to C4) for user data are typically added to the last part of user data (U1 to U8).
  • the arrangement of each data may be rearranged by interleaving or the like.
  • auxiliary data is input to the second encoding unit 130.
  • the second encoding unit 130 adds an error correction code to the auxiliary data (step S32).
  • the auxiliary data also has an error correction capability like the user data.
  • the error correction code (E1) for the auxiliary data is typically added to the last part of the auxiliary data (A1 and A2).
  • the arrangement of each data may be rearranged by interleaving or the like.
  • the change information generation unit 170 generates change information for changing the auxiliary data based on the input user data (step S33).
  • the change information for example, a hash value generated by a hash function can be used.
  • SHA-1 Secure Hash Algorithm 1
  • an input value of an arbitrary length that is, user data
  • a 160-bit output value that is, change information
  • the change information is information uniquely obtained from user data, such as a hash value.
  • the change information generated in the change information generation unit 170 is input to the change unit 180.
  • auxiliary data encoded by the second encoding unit 130 is also input to the changing unit 180.
  • the changing unit 180 changes the auxiliary data based on the change information (step S34).
  • change information such as 7, 2, 5, 6, 8,... Is generated from the user data (U1 to U8) by the change information generation unit 170.
  • the changing unit 180 changes the auxiliary data by performing arithmetic processing using each value of the change information and the auxiliary data.
  • the arithmetic processing here (that is, “+” shown in the figure) is an XOR operation.
  • the auxiliary data A1 is set to A1 ′ by performing an XOR operation with the leading value “7” of the change information.
  • the auxiliary data A2 is set to A2 'by performing an XOR operation with the second value "2" of the change information.
  • the error correction code E1 added to the auxiliary data is set to E1 ′ by performing an XOR operation with the third value “5” of the change information.
  • the number of values of change information is the number of pieces of auxiliary data to be replaced (that is, A1, A2, and E1 here). It is desirable to be equal to or more than (3). However, if, for example, a hash function is used as change information, the number of auxiliary data values is greater than the hash value, and if the change information value is insufficient, the output of the hash function is further input to the hash function. It is possible to cope with this by generating the obtained value (that is, the hash value of the hash value).
  • the auxiliary data (A1 ′, A2 ′, and E1 ′) changed by the position information is output to the replacement unit 140, respectively.
  • the replacement unit replaces each changed auxiliary data with the user data at position 3 in each block of user data (step S35). Specifically, as shown in FIG. 21, the leading value A1 'of the auxiliary data is replaced with U4 located at position 3 in the first block of user data. The second value A2 'of the auxiliary data is replaced with U8 located at position 3 in the second block of user data. The error correction code value E1 'of the auxiliary data is replaced with C4 located at position 3 in the third block of user data.
  • auxiliary data can be embedded relatively easily and evenly in user data. Since the user data is replaced with auxiliary data after an error correction code is added, the replaced auxiliary data is treated as an intentional error.
  • auxiliary data and the data located at position 3 in the user data are replaced, but such a replacement rule is a design matter and can be changed as appropriate.
  • the law used for the replacement is not particularly limited.
  • the modulation unit 150 modulates the user data into a method suitable for recording (step S36).
  • the writing unit 160 records the modulated user data in the holographic memory 300 (step S37).
  • the change information used for changing the auxiliary data is not recorded in the holographic memory 300.
  • it is not necessary to record on another recording medium. Therefore, the size of the data recorded here is the same as the size of the user data to be recorded.
  • the information reproducing apparatus 200 includes a reading unit 210, a demodulating unit 220, a decoding unit 230, an extracting unit 250, a second decoding unit 260, and a second change information generating unit 270. And a re-changing unit 280.
  • the reading unit 210 includes, for example, a light emitting unit, a lens, and a light receiving element.
  • the reading unit 210 detects an image obtained by irradiating the holographic memory 300 with laser light by the light receiving element, and user data is detected from the detected image. Play.
  • the demodulator 220 demodulates the user data modulated by the modulator 150 in the information generation apparatus 100 to the original state. That is, the reverse process of the modulation unit 150 is performed.
  • the decoding unit 230 is an example of the “decoding unit” of the present invention, and corrects an error included in user data using an error correction code added to the user data.
  • the extraction unit 250 is an example of the “extraction unit” of the present invention, and a replacement rule when information is generated from user data before decoding (that is, user data in which auxiliary data is included as an intentional error). To extract auxiliary data.
  • the second decoding unit 260 corrects an error included in the auxiliary data by using an error correction code added to the extracted auxiliary data.
  • the second change information generation unit 270 is an example of the “second change information generation unit” of the present invention, and the information generation device uses the user data decoded by the decoding unit 230 (that is, user data whose error is corrected).
  • the change information is generated in the same manner as the change information generation unit 170 in 100.
  • the change information generation unit 170 can also be used as the second change information generation unit 270.
  • the re-change unit 280 is an example of the “re-change unit” of the present invention. Based on the change information generated by the second change information generation unit 270, the re-change unit 280 performs various operations on the auxiliary data changed by the change unit 180. By performing the processing, it is re-changed to the auxiliary data before the change.
  • FIG. 22 is a flowchart showing an operation flow of the information reproducing apparatus according to the fifth embodiment.
  • FIG. 23 is a conceptual diagram illustrating a method for generating user data decoding and change information
  • FIG. 24 is a conceptual diagram illustrating auxiliary data extraction and re-change and a decoding method.
  • the reading unit 210 first reads user data recorded in the holographic memory 300 (step S41). Subsequently, the demodulator 220 demodulates the read user data to a state before modulation (step S42).
  • the decoding unit 230 corrects the error included in the user data using the error correction code added to the user data (step S43).
  • the auxiliary data replaced with part of the user data by the replacement unit 140 in the information generating apparatus 100 is corrected as an error. That is, the auxiliary data is user data before replacement.
  • the decrypted user data is output to the outside as a reproduction result and also output to the second change information generation unit 270.
  • the second change information generation unit 270 generates change information using the decrypted user data (step S44).
  • user data (D1 to D12) read by the reading unit 210 includes scratches in the holographic memory 300, noise during recording and reproduction, in addition to auxiliary data that is an intentional error. Etc., some errors are included.
  • the decoding unit 230 decodes the user data including such an error and uses it as user data (U1 to U8) before replacement. Since the user data is the same data as the user data used by the change information generation unit 170 in the information generation apparatus 100, the change information generated in the second change information generation unit 270 is generated in the change information generation unit 170. It becomes the same as the changed information. As described above, if the user data can be decoded, the second change information generation unit 270 can generate the same change information again. Therefore, it is not necessary to record the change information generated in the change information generation unit 120 in the holographic memory 300 or another recording medium.
  • user data before being decoded by the decoding unit 230 is also output to the extraction unit 250.
  • the extraction unit 250 extracts auxiliary data from user data before decoding (step S45).
  • the extracted auxiliary data is output to the re-changing unit 280.
  • the change information generated in the second change information generation unit 270 is also output to the re-change unit 280.
  • the re-change unit 280 re-changes the extracted auxiliary data based on the change information (step S46).
  • the extraction unit 250 extracts data from the position of the position 3 of each block in the user data (D1 to D12) before decoding. As a result, the auxiliary data that has been replaced is extracted. Since the auxiliary data (D4, D8, and D12) extracted here is changed by the changing unit 180, the re-changing unit 280 re-changes the auxiliary data extracted based on the change information. For example, when the auxiliary data is changed by the XOR operation processing as described above, the XOR operation processing is performed again using the position information, thereby canceling the effect of the XOR operation processing, and the auxiliary data is restored to the original value (A1 , A2 and E1). It should be noted that arithmetic processing other than XOR arithmetic processing can be used as long as the arithmetic processing can reversibly change auxiliary data using position information.
  • the error is corrected in the auxiliary data after re-change in the second decoding unit and decoded into auxiliary data (A1 and A2) before encoding (step S47).
  • the decoded auxiliary data is output to the outside as a reproduction result.
  • the security of auxiliary data can be improved. Further, since the change information used for changing the auxiliary data is replaced with a part of the user data and recorded, it is possible to prevent the information to be recorded from increasing.
  • FIGS. 25 and 29 are conceptual diagrams showing data output from the encoding unit
  • FIG. 26 is a conceptual diagram showing data output from the second encoding unit
  • 27 and 28 are conceptual diagrams showing the division of auxiliary data, respectively.
  • the auxiliary data is embedded as an intentional error, and an error is further generated with respect to the assumed error. Therefore, in order to prevent error correction from being impossible, it is desirable to carefully determine the parameters of the error correction code so that sufficient error correction can be performed.
  • the size of user data which is the processing unit of the encoding unit 110 (see FIG. 1), is k symbols, and the output size is n symbols. That is, an error correction code of nk symbols is added to user data.
  • the maximum e symbols out of n symbols are erroneous, that is, the error correction capability in the encoding unit 110 is e symbols
  • the following equation (1), e ⁇ (n ⁇ k) / 2 (1) N and k may be selected to satisfy the above.
  • a component namely, “scratch error” in the figure
  • the size of the auxiliary data that is processed by the second encoding unit 130 is k ′ symbol and the output size is n ′ symbol.
  • the maximum e ′ symbol among n ′ symbols is erroneous, that is, the error correction capability in the second encoding unit 130 is the e ′ symbol
  • the following equation (2), e ′ ⁇ (n′ ⁇ k ′) / 2 (2) N ′ and k ′ may be selected so as to satisfy the above.
  • the second encoding unit 130 divides the input auxiliary data into k ′ symbols, for example, and adds an error correction code.
  • ⁇ which is the number of error correction code generation and addition processing is expressed by the following equation (3), A ⁇ ⁇ k ′ (3) Should be satisfied. Since A is not always a multiple of k ′, in such a case, dummy data may be added to the auxiliary data or zero padding may be performed as shown in the figure.
  • the basic processing unit of the second encoding unit 130 is n ′ symbols, so user data is replaced with auxiliary data divided into k ′ symbols.
  • the user data of n ′ symbols including the error correction code to be added may be replaced. Therefore, in order to replace user data with auxiliary data for A symbols, the user data for ⁇ ′n ′ symbols may be replaced.
  • the present invention is not limited to the above-described embodiments, and can be appropriately changed without departing from the spirit or idea of the invention that can be read from the claims and the entire specification, and information accompanying such changes.
  • the generating device and method, the information reproducing device and method, and the recording medium are also included in the technical scope of the present invention.
  • the information generating apparatus and method, the information reproducing apparatus and method, and the recording medium of the present invention can be used for a recording apparatus that records information on a recording medium such as a holographic memory or a reproducing apparatus that reproduces stored information. . It can also be used in communication devices that exchange information via the Internet or the like.

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Computer Security & Cryptography (AREA)
  • Signal Processing For Digital Recording And Reproducing (AREA)

Abstract

Information generating equipment (100) replaces part of user data with auxiliary data to generate replaced user data. The information generating equipment comprises an encoding means (110) which adds an error correction code to the user data and generates encoded data, a position information generating means (120) which generates position information that indicates the position of the data in the encoded data to be replaced with the auxiliary data based on the user data, and replacement means (140) which generates the replaced user data by replacing part of the encoded data with the auxiliary data based on the position information. Due to this structure, information which can surely reproduce the auxiliary data can be generated while avoiding various practical inconveniences.

Description

情報生成装置及び方法、情報再生装置及び方法、並びに記録媒体Information generating apparatus and method, information reproducing apparatus and method, and recording medium
　本発明は、誤り訂正符号を用いた情報生成装置及び方法、情報再生装置及び方法、並びに記録媒体の技術分野に関する。 The present invention relates to an information generation apparatus and method using an error correction code, an information reproduction apparatus and method, and a technical field of a recording medium.
　この種の情報生成装置として、ユーザデータに関連する補助データを、誤り訂正符号を付加したユーザデータに対して意図的な誤りとして埋め込むものがある。例えば特許文献１では、ユーザデータが不正に複製されたものであるか否かを識別する識別データを意図的な誤りとして埋め込み、誤りの位置を示す情報を暗号化して別途記録するという技術が開示されている。また特許文献２では、誤りを埋め込んだ位置を、誤り訂正前後のデータを互いに比較することで検出するという技術が開示されている。 As this type of information generation device, there is a device that embeds auxiliary data related to user data as intentional error in user data to which an error correction code is added. For example, Patent Document 1 discloses a technique in which identification data for identifying whether user data is illegally copied is embedded as an intentional error, and information indicating the position of the error is encrypted and recorded separately. Has been. Patent Document 2 discloses a technique for detecting a position where an error is embedded by comparing data before and after error correction.
特開平８－２１２６８１号公報Japanese Patent Laid-Open No. 8-212682 特許第３４４９８０４号公報Japanese Patent No. 3449804
　しかしながら、上述した特許文献１に係る技術では、誤りの位置を示す情報を別途記録することが求められるため、その分ユーザデータを記録できる領域が減少してしまう。また、誤りの位置を示す情報に誤りが生じてしまった場合には、誤りの位置を検出することができなくなってしまうおそれがある。 However, in the technique according to Patent Document 1 described above, since information indicating an error position is required to be recorded separately, an area where user data can be recorded decreases accordingly. Further, when an error occurs in the information indicating the error position, the error position may not be detected.
　また、上述した特許文献２に係る技術では、誤り訂正前後のデータを互いに比較することがもとめられるため、誤りの位置を検出しようとする際の処理量が比較的多くなってしまうおそれがある。 Further, in the technique according to Patent Document 2 described above, since it is required to compare the data before and after error correction, there is a possibility that the amount of processing when detecting the position of the error is relatively large.
　以上のように、上述した技術には、実践上の様々な不都合が生じてしまうおそれがあるという技術的問題点がある。 As described above, the above-described technique has a technical problem that various inconveniences may occur in practice.
　本発明は、例えば上述した問題点に鑑みなされたものであり、データ量の増大を防止しつつ、補助データを確実に再生可能な情報を生成することができる情報生成装置及び方法、情報再生装置及び方法、並びに記録媒体を提供することを課題とする。 The present invention has been made in view of the above-described problems, for example, and an information generation apparatus and method, and an information reproduction apparatus capable of generating information that can reliably reproduce auxiliary data while preventing an increase in the amount of data. And a method and a recording medium.
　本発明の第１の情報生成装置は上記課題を解決するために、ユーザデータの一部を、前記ユーザデータに関連するデータであって、前記ユーザデータとは異なる用途で用いられる補助データに置換して、置換ユーザデータを生成する情報生成装置であって、前記ユーザデータに対して誤り訂正符号を付加して、符号化データを生成する符号化手段と、前記符号化データにおける前記補助データに置換されるデータの位置を示す位置情報を、前記ユーザデータに基づいて生成する位置情報生成手段と、前記符号化データの一部を、前記位置情報に基づいて前記補助データに置換して、前記置換ユーザデータを生成する置換手段とを備える。 In order to solve the above-described problem, the first information generation apparatus of the present invention replaces a part of user data with auxiliary data that is related to the user data and is used for a purpose different from the user data. An information generation apparatus for generating replacement user data, wherein an error correction code is added to the user data to generate encoded data, and the auxiliary data in the encoded data is added to the auxiliary data. Position information generating means for generating position information indicating the position of data to be replaced based on the user data, and replacing a part of the encoded data with the auxiliary data based on the position information, Replacement means for generating replacement user data.
　本発明の第１の情報生成装置によれば、ユーザデータの一部が、補助データに置換されることで、置換ユーザデータが生成される。尚、「ユーザデータ」とは、生成される置換ユーザデータの元となるデータであり、例として電子ファイル、音声データ、画像データ等が挙げられる。また、「補助データ」とは、ユーザデータに関連する補助的なデータであり、ユーザデータとは異なる用途で用いられる。補助データの例として、ユーザデータの属性、ファイル名前及び管理番号等を示すデータや、分割されたユーザデータの分割位置を示すデータ、ユーザデータが不正にコピーされたデータであるか否かを識別するためのデータ等が挙げられる。補助データは、典型的には、ユーザデータと比べると極めて情報量の少ないデータである。 According to the first information generation apparatus of the present invention, replacement user data is generated by replacing part of user data with auxiliary data. The “user data” is data that is the basis of generated replacement user data, and examples thereof include electronic files, audio data, and image data. “Auxiliary data” is auxiliary data related to user data, and is used for purposes different from user data. As an example of auxiliary data, data indicating user data attributes, file name, management number, etc., data indicating the division position of divided user data, and whether or not user data is illegally copied data Data and the like. The auxiliary data is typically data with a very small amount of information compared to user data.
　生成された置換ユーザデータは、例えば所定の方式で変調された後、ホログラフィックメモリや光ディスク等の記録媒体に記録されたり、インターネット等のネットワークを用いて伝送される。 The generated replacement user data is modulated by a predetermined method, for example, and then recorded on a recording medium such as a holographic memory or an optical disk, or transmitted using a network such as the Internet.
　本発明の第１の情報生成装置の動作時には、先ず符号化手段によって、ユーザデータに誤り訂正符号が付加され、符号化データが生成される。続いて、位置情報生成手段によって、符号化データにおける補助データに置換されるデータの位置を示す位置情報が生成される。 In the operation of the first information generating apparatus of the present invention, first, the error correction code is added to the user data by the encoding means, and the encoded data is generated. Subsequently, position information indicating the position of the data to be replaced with the auxiliary data in the encoded data is generated by the position information generating means.
　ここで特に、位置情報は、ユーザデータに基づいて生成される。即ち、位置情報は、ユーザデータを用いた所定の処理により生成される。位置情報は、例えばハッシュ関数により生成されるハッシュ値のように、ユーザデータから一意的に求められる情報であれば、直接的にデータの位置を示すような情報でなくともよい。このような場合は、例えば位置情報が有する値と、置換するデータの位置とを対応させるような法則を予め設定しておくことで、置換されるデータの位置が示される。 Here, in particular, the position information is generated based on user data. That is, the position information is generated by a predetermined process using user data. If the position information is information uniquely obtained from user data such as a hash value generated by a hash function, for example, the position information may not be information directly indicating the position of the data. In such a case, for example, the position of data to be replaced is indicated by setting in advance a rule that associates the value of the position information with the position of the data to be replaced.
　位置情報が生成されると、置換手段により、符号化データの一部が位置情報に基づいて補助データに置換され、置換ユーザデータが生成される。補助データは、符号化後に置換されるため、ユーザデータに意図的な誤りとして埋め込まれることとなる。 When the position information is generated, a part of the encoded data is replaced with auxiliary data based on the position information by the replacement means, and replacement user data is generated. Since the auxiliary data is replaced after encoding, it is embedded in the user data as an intentional error.
　上述したように生成された置換ユーザデータは、ユーザデータとして再生される際に、誤り訂正符号により誤りを訂正することで復号される。この際、置換された補助データは、ユーザデータにおける誤りとして扱われてしまうため、復号後のユーザデータには残らない。しかしながら、ユーザデータを復号することができれば、ユーザデータから再び位置情報を生成することができる。よって、位置情報に基づいて、容易且つ確実に復号前の置換ユーザデータから補助データを抽出することが可能となる。 The replacement user data generated as described above is decoded by correcting an error with an error correction code when reproduced as user data. At this time, since the replaced auxiliary data is handled as an error in the user data, it does not remain in the decoded user data. However, if the user data can be decoded, the position information can be generated again from the user data. Therefore, auxiliary data can be easily and reliably extracted from replacement user data before decoding based on position information.
　本発明では特に、補助データがユーザデータの一部として置換されているため、補助データを別のデータとして扱う場合と比較して、データ全体の大きさを小さくすることができる。また、位置情報についても、ユーザデータから生成できるので、保持しておかなくともよい。よって、データ量の増大を効果的に防止することが可能である。 Especially in the present invention, since the auxiliary data is replaced as a part of the user data, the size of the entire data can be reduced as compared with the case where the auxiliary data is handled as another data. Also, the position information can be generated from the user data, so it is not necessary to keep it. Therefore, it is possible to effectively prevent an increase in data amount.
　本発明では更に、上述したように、位置情報を保持しておかなくともよいため、位置情報に誤りが発生することに起因して、補助データを再生できなくなってしまうことを防止できる。即ち、ユーザデータさえ再生できるような状態にあれば、補助データも確実に再生することが可能である。 In the present invention, as described above, since it is not necessary to store the position information, it is possible to prevent the auxiliary data from being reproduced due to an error in the position information. That is, auxiliary data can be reliably reproduced as long as even user data can be reproduced.
　また、単にユーザデータにおける誤りを補助データとして抽出しようとすると、例えば記録媒体における傷や通信時のノイズ等によって発生したノイズとの判別が行えない。このため、置換ユーザデータに誤りが多く発生してしまうような場合には、補助データを抽出することは困難となってしまう。このような場合であっても、本発明に係る置換ユーザデータによれば、ユーザデータから位置情報を生成することができるため、確実に補助データのみを抽出することが可能である。 Also, if an error in user data is simply extracted as auxiliary data, it cannot be distinguished from noise generated due to scratches in the recording medium, noise during communication, or the like. For this reason, when many errors occur in the replacement user data, it is difficult to extract the auxiliary data. Even in such a case, according to the replacement user data according to the present invention, the position information can be generated from the user data, so that it is possible to reliably extract only the auxiliary data.
　以上説明したように、本発明の第１の情報生成装置によれば、実践上の様々な不都合を回避しつつ、補助データを確実に再生可能な情報を生成することができる。 As described above, according to the first information generating apparatus of the present invention, it is possible to generate information that can reliably reproduce auxiliary data while avoiding various practical inconveniences.
　本発明の第１の情報生成装置の一態様では、前記符号化データは、所定数の連続するデータ毎にブロックとして分割されており、前記置換手段は、前記ブロック毎に、前記符号化データを１つの補助データと置換する。 In one aspect of the first information generating apparatus of the present invention, the encoded data is divided into blocks for each predetermined number of continuous data, and the replacement means converts the encoded data for each block. Replace with one auxiliary data.
　この態様によれば、符号化データは、所定数の連続するデータ毎にブロックとして分割されている。尚、ここでの「分割」は、符号化データが複数のデータとして扱われることを意味するものではなく、データ中に区切りが存在しているという意味である。 According to this aspect, the encoded data is divided into blocks for each predetermined number of continuous data. Here, “division” does not mean that encoded data is handled as a plurality of data, but means that there is a delimiter in the data.
　本態様では特に、補助データは、ブロック毎に符号化データの１つと置換される。即ち、符号化データにおける各ブロックにおいて、ブロックを構成するデータのうち、１つのデータが補助データに置換される。これにより、補助データは、置換ユーザデータ内に好適に分散される。よって、補助データの殆ど或いは全てに誤りが発生してしまい、補助データが再生できなくなってしまうことを効果的に防止することができる。 Particularly in this aspect, the auxiliary data is replaced with one of the encoded data for each block. That is, in each block in the encoded data, one piece of data constituting the block is replaced with auxiliary data. As a result, the auxiliary data is preferably distributed in the replacement user data. Therefore, it is possible to effectively prevent an error from occurring in most or all of the auxiliary data and the auxiliary data from being reproduced.
　尚、補助データが比較的情報量の多いデータである場合には、補助データを、ブロック毎に所定数（即ち、２以上）の符号化データと置換することによっても、上述した効果は相応に得られる。即ち、ブロック毎に２つの補助データを２つの符号化データと置換したり、３つの補助データを３つの符号化データと置換したりしてもよい。 If the auxiliary data is data having a relatively large amount of information, the above effect can be obtained by replacing the auxiliary data with a predetermined number (ie, 2 or more) of encoded data for each block. can get. That is, for each block, two auxiliary data may be replaced with two encoded data, or three auxiliary data may be replaced with three encoded data.
　本発明の第１の情報生成装置の他の態様では、前記補助データに対して誤り訂正符号を付加する補助符号化手段を更に備え、前記置換手段は、前記符号化データの一部を前記誤り訂正符号が付加された補助データに置換して、置換ユーザデータを生成する。 In another aspect of the first information generating apparatus of the present invention, the information processing device further includes auxiliary encoding means for adding an error correction code to the auxiliary data, and the replacement means converts a part of the encoded data to the error. Substitution user data is generated by substituting the auxiliary data to which the correction code is added.
　この態様によれば、補助符号化手段によって、補助データに対しても誤り訂正符号が付加されている。即ち、補助データも、ユーザデータ同様に符号化されている。尚、ユーザデータ及び補助データの符号化方式は、互いに同じであってもよいし、異なっていてもよい。 According to this aspect, the error correction code is also added to the auxiliary data by the auxiliary encoding means. That is, auxiliary data is encoded in the same manner as user data. Note that the encoding methods of user data and auxiliary data may be the same or different.
　補助データが符号化されていることにより、補助データに誤りが生じた場合であっても、誤り訂正符号によって正しいデータへと復号できる。よって本態様では、補助データをより確実に再生することが可能である。 Since the auxiliary data is encoded, even if an error occurs in the auxiliary data, it can be decoded into correct data by the error correction code. Therefore, in this aspect, auxiliary data can be reproduced more reliably.
　本発明の第１の情報生成装置の他の態様では、前記補助データによって、前記ユーザデータを暗号化することで暗号化されたユーザデータを生成する暗号化手段を更に備え、前記符号化手段は、前記暗号化されたユーザデータに対して誤り訂正符号を付加して、符号化データを生成し、前記位置情報生成手段は、前記位置情報を、前記暗号化されたユーザデータに基づいて生成する。 In another aspect of the first information generating apparatus of the present invention, the information generating device further comprises: encryption means for generating user data encrypted by encrypting the user data with the auxiliary data; The error correction code is added to the encrypted user data to generate encoded data, and the position information generating means generates the position information based on the encrypted user data .
　この態様によれば、ユーザデータは、符号化手段によって符号化される前に、暗号化手段によって暗号化される。また、ユーザデータの暗号化には補助データが用いられる。即ち、補助データはユーザデータの暗号化を解除する鍵情報と考えることもできる。但し、補助データは、ユーザデータを暗号化するためのデータ以外のデータを含んでいてもよい。 According to this aspect, the user data is encrypted by the encryption means before being encoded by the encoding means. Also, auxiliary data is used for encrypting user data. That is, the auxiliary data can be considered as key information for decrypting the user data. However, the auxiliary data may include data other than data for encrypting user data.
　補助データは、上述したように、置換ユーザデータの一部と置換されるため、データの増大には繋がらない。また、ユーザデータから生成される位置情報により、確実に抽出できる。従って、より好適にユーザデータを暗号化できる。 As described above, the auxiliary data is replaced with a part of the replacement user data, and thus does not increase the data. Moreover, it can extract reliably by the positional information produced | generated from user data. Therefore, user data can be encrypted more suitably.
　本態様では、ユーザデータが暗号化されているため、ユーザデータに対するセキュリティを向上させることができる。また、位置情報についても、鍵情報がないと正しく生成することができないため、同様にセキュリティを向上させることができる。 In this aspect, since the user data is encrypted, the security for the user data can be improved. Further, since the position information cannot be generated correctly without the key information, the security can be similarly improved.
　本発明の第１の情報生成装置の他の態様では、前記位置情報生成手段は、前記位置情報を、前記ユーザデータに加えて鍵情報に基づいて生成する。 In another aspect of the first information generating apparatus of the present invention, the position information generating means generates the position information based on key information in addition to the user data.
　この態様によれば、位置情報手段は、ユーザデータに加えて鍵情報に基づいて生成される。例えば、位置情報はユーザデータに基づいて仮の位置情報として生成された後、鍵情報に基づいて暗号化されることで生成される。或いは、鍵情報によって暗号化されたユーザデータに基づいて生成されてもよい。また、ＨＭＡＣ（Keyed-Hashing for Message Authentication Code）を用いて、ユーザデータ及び鍵情報から直接的に生成することも可能である。 According to this aspect, the position information means is generated based on the key information in addition to the user data. For example, the position information is generated as temporary position information based on user data and then encrypted based on key information. Alternatively, it may be generated based on user data encrypted with the key information. It is also possible to generate directly from user data and key information using HMAC (Keyed-Hashingashfor Message Authentication Code).
　本態様では、位置情報を暗号化された状態で生成するため、位置情報を正しく生成する際には鍵情報が求められる。即ち、鍵情報がない場合に、位置情報を正しく生成することができないようにすることができるため、位置情報に対するセキュリティを向上させることができる。よって、位置情報を用いることで抽出される補助データに対するセキュリティを効果的に高めることが可能である。 In this aspect, since the position information is generated in an encrypted state, key information is required when correctly generating the position information. In other words, when there is no key information, it is possible to prevent the position information from being correctly generated, so that the security for the position information can be improved. Therefore, it is possible to effectively increase security for auxiliary data extracted by using position information.
　本発明の第１の情報生成装置の他の態様では、前記位置情報を用いて、前記補助データを変更する補助データ変更手段を更に備える。 In another aspect of the first information generating apparatus of the present invention, the information generating device further includes auxiliary data changing means for changing the auxiliary data using the position information.
　この態様によれば、補助データは、符号化データと置換される前に位置情報を用いて変更される。尚、ここでの「変更」とは、可逆的な変更であり、変更された補助データは、再び位置情報を用いて元の補助データに戻すことが可能である。即ち、ここでの変更は、位置情報を鍵情報とした、補助データの暗号化とも呼ぶことができる。 According to this aspect, the auxiliary data is changed using the position information before being replaced with the encoded data. The “change” here is a reversible change, and the changed auxiliary data can be returned to the original auxiliary data using the position information again. That is, the change here can also be called auxiliary data encryption using position information as key information.
　位置情報を用いて補助データを変更することで、補助データに対するセキュリティを向上させることができる。また、位置情報は、ユーザデータに基づいて生成することができるため、ユーザデータと別に保持されなくともよい。従って、情報量が不必要に増大してしまうことを防止できる。 * The security for auxiliary data can be improved by changing the auxiliary data using location information. Further, since the position information can be generated based on the user data, it does not have to be held separately from the user data. Therefore, it is possible to prevent the amount of information from increasing unnecessarily.
　本発明の第２の情報生成装置は上記課題を解決するために、ユーザデータの一部を、前記ユーザデータに関連するデータであって、前記ユーザデータとは異なる用途で用いられる補助データに置換して、置換ユーザデータを生成する情報生成装置であって、前記ユーザデータに対して誤り訂正符号を付加して、符号化データを生成する符号化手段と、前記補助データを変更補助データに変更するための変更情報を、前記ユーザデータに基づいて生成する変更情報生成手段と、前記変更情報を用いて、前記補助データを変更補助データに変更する補助データ変更手段と、前記符号化データの一部を、前記変更補助データに置換して、前記置換ユーザデータを生成する置換手段とを備える。 In order to solve the above-described problem, the second information generation apparatus of the present invention replaces a part of user data with auxiliary data that is related to the user data and is used for a purpose different from the user data. An information generation device for generating replacement user data, wherein an error correction code is added to the user data to generate encoded data, and the auxiliary data is changed to change auxiliary data Change information generating means for generating change information to be changed based on the user data, auxiliary data changing means for changing the auxiliary data to change auxiliary data using the change information, and one of the encoded data A replacement means for replacing the change auxiliary data with the change auxiliary data and generating the replacement user data.
　本発明の第２の情報生成装置によれば、ユーザデータの一部が、補助データに置換されることで、置換ユーザデータが生成される。尚、「ユーザデータ」とは、生成される置換ユーザデータの元となるデータであり、例として電子ファイル、音声データ、画像データ等が挙げられる。また、「補助データ」とは、ユーザデータに関連する補助的なデータであり、ユーザデータとは異なる用途で用いられる。補助データの例として、ユーザデータの属性、ファイル名前及び管理番号等を示すデータや、分割されたユーザデータの分割位置を示すデータ、ユーザデータが不正にコピーされたデータであるか否かを識別するためのデータ等が挙げられる。補助データは、典型的には、ユーザデータと比べると極めて情報量の少ないデータである。 According to the second information generating apparatus of the present invention, replacement user data is generated by replacing part of user data with auxiliary data. The “user data” is data that is the basis of generated replacement user data, and examples thereof include electronic files, audio data, and image data. “Auxiliary data” is auxiliary data related to user data, and is used for purposes different from user data. As an example of auxiliary data, data indicating user data attributes, file name, management number, etc., data indicating the division position of divided user data, and whether or not user data is illegally copied data Data and the like. The auxiliary data is typically data with a very small amount of information compared to user data.
　生成された置換ユーザデータは、例えば所定の方式で変調された後、ホログラフィックメモリや光ディスク等の記録媒体に記録されたり、インターネット等のネットワークを用いて伝送される。 The generated replacement user data is modulated by a predetermined method, for example, and then recorded on a recording medium such as a holographic memory or an optical disk, or transmitted using a network such as the Internet.
　本発明の第２の情報生成装置の動作時には、先ず符号化手段によって、ユーザデータに誤り訂正符号が付加され、符号化データが生成される。続いて、変更情報生成手段によって、補助データを変更補助データに変更するための変更情報が生成される。尚、ここでの「変更」とは、可逆的な変更であり、変更された補助データは、再び変更情報を用いて元の補助データに戻すことが可能である。 In the operation of the second information generating apparatus of the present invention, first, the error correction code is added to the user data by the encoding means to generate encoded data. Subsequently, change information for changing auxiliary data to change auxiliary data is generated by the change information generating means. The “change” here is a reversible change, and the changed auxiliary data can be returned to the original auxiliary data using the change information again.
　ここで特に、変更情報は、ユーザデータに基づいて生成される。即ち、変更情報は、ユーザデータを用いた所定の処理により生成される。変更情報は、例えばハッシュ関数により生成されるハッシュ値のように、ユーザデータから一意的に求められる情報であればよい。変更補助データは、例えば変更情報を鍵情報として、補助データが暗号化されることにより生成される。即ち、変更情報を用いて補助データを変更することで、補助データに対するセキュリティを向上させることができる。 Here, in particular, the change information is generated based on user data. That is, the change information is generated by a predetermined process using user data. The change information may be information uniquely obtained from user data such as a hash value generated by a hash function. The change auxiliary data is generated, for example, by encrypting the auxiliary data using the change information as key information. In other words, the security for the auxiliary data can be improved by changing the auxiliary data using the change information.
　変更補助データが生成されると、置換手段により、符号化データの一部が変更補助データに置換され、置換ユーザデータが生成される。変更補助データは、符号化後に置換されるため、ユーザデータに意図的な誤りとして埋め込まれることとなる。 When the change auxiliary data is generated, a part of the encoded data is replaced with the change auxiliary data by the replacement means, and replacement user data is generated. Since the change auxiliary data is replaced after encoding, it is embedded in the user data as an intentional error.
　上述したように生成された置換ユーザデータは、ユーザデータとして再生される際に、誤り訂正符号により誤りを訂正することで復号される。この際、置換された変更補助データは、ユーザデータにおける誤りとして扱われてしまうため、復号後のユーザデータには残らない。しかしながら、例えば置換された変更補助データの位置を示す位置情報を別途記憶しておく、或いは置換する変更補助データの位置を予め設定しておくことで、変更補助データを好適に抽出することが可能である。また、誤り訂正前後のユーザデータ、即ち置換ユーザデータと復号後のユーザデータとを比較することで変更補助データを抽出することができる。 The replacement user data generated as described above is decoded by correcting an error with an error correction code when reproduced as user data. At this time, the changed change auxiliary data is handled as an error in the user data, and therefore does not remain in the decoded user data. However, for example, it is possible to suitably extract the change auxiliary data by separately storing position information indicating the position of the replaced change auxiliary data, or by previously setting the position of the change auxiliary data to be replaced. It is. Further, change auxiliary data can be extracted by comparing user data before and after error correction, that is, replacement user data and decoded user data.
　抽出された変更補助データは、変更情報に基づいて元の補助データに再変更することができる。変更情報は、ユーザデータから生成できるので、保持しておかなくともよい。変更情報に誤りが発生することに起因して、補助データを元に戻すことができなくなってしまうことを防止できる。即ち、ユーザデータさえ再生できるような状態にあれば、補助データも確実に再生することが可能である。 The extracted change auxiliary data can be changed back to the original auxiliary data based on the change information. Since the change information can be generated from user data, it does not have to be retained. It can be prevented that the auxiliary data cannot be restored due to an error in the change information. That is, auxiliary data can be reliably reproduced as long as even user data can be reproduced.
　また、変更情報を保持しておかなくともよい分、データ量の増大を防止することが可能である。また、補助データについても、ユーザデータの一部として置換されているため、補助データを別のデータとして扱う場合と比較して、データ全体の大きさを小さくすることができる。 Also, it is possible to prevent an increase in the amount of data as much as it is not necessary to retain the change information. Further, since the auxiliary data is also replaced as a part of the user data, the size of the entire data can be reduced as compared with the case where the auxiliary data is handled as another data.
　以上説明したように、本発明の第２の情報生成装置によれば、高いセキュリティを実現しつつ、補助データを確実に再生可能な情報を生成することができる。 As described above, according to the second information generating apparatus of the present invention, information capable of reliably reproducing auxiliary data can be generated while realizing high security.
　本発明の第１の記録媒体は上記課題を解決するために、上述した本発明の第１の情報生成装置によって生成された置換ユーザデータが記録されている。 In the first recording medium of the present invention, replacement user data generated by the above-described first information generating apparatus of the present invention is recorded in order to solve the above-described problems.
　本発明の第１の記録媒体によれば、上述した本発明の第１の情報生成装置によって生成された置換ユーザデータが記録されているため、記録されたデータを再生する際に、確実に誤り位置を検出して、ユーザデータ中の補助データを抽出することができる。また、補助データや位置情報をユーザデータとは別に記録しなくともよいため、ユーザデータを記録する領域を十分に確保することが可能である。 According to the first recording medium of the present invention, since the replacement user data generated by the first information generation apparatus of the present invention described above is recorded, it is ensured that an error will occur when the recorded data is reproduced. By detecting the position, auxiliary data in the user data can be extracted. In addition, since auxiliary data and position information need not be recorded separately from user data, it is possible to secure a sufficient area for recording user data.
　本発明の第２の記録媒体は上記課題を解決するために、上述した本発明の第２の情報生成装置によって生成された置換ユーザデータが記録されている。 In the second recording medium of the present invention, replacement user data generated by the above-described second information generating apparatus of the present invention is recorded in order to solve the above problems.
　本発明の第２の記録媒体によれば、上述した本発明の第２の情報生成装置によって生成された置換ユーザデータが記録されているため、記録されたデータを再生する際に、高いセキュリティを実現しつつ、ユーザデータ中の補助データを確実に抽出することができる。また、補助データや位置情報をユーザデータとは別に記録しなくともよいため、ユーザデータを記録する領域を十分に確保することが可能である。 According to the second recording medium of the present invention, since the replacement user data generated by the above-described second information generating apparatus of the present invention is recorded, high security is ensured when the recorded data is reproduced. While realizing, auxiliary data in user data can be reliably extracted. In addition, since auxiliary data and position information need not be recorded separately from user data, it is possible to secure a sufficient area for recording user data.
　本発明の第１の情報再生装置は上記課題を解決するために、上述した本発明の第１の情報生成装置によって生成された置換ユーザデータを再生する情報再生装置であって、前記置換ユーザデータを、前記誤り訂正符号を用いて、前記ユーザデータに復号する復号手段と、前記位置情報を、前記復号されたユーザデータに基づいて生成する第２位置情報生成手段と、前記第２位置情報生成手段によって生成された前記位置情報に基づいて、前記置換ユーザデータから前記補助データを抽出する抽出手段とを備える。 In order to solve the above problems, a first information reproducing apparatus of the present invention is an information reproducing apparatus for reproducing replacement user data generated by the above-described first information generating apparatus of the present invention, wherein the replacement user data Decoding means for decoding the user data into the user data using the error correction code, second position information generating means for generating the position information based on the decoded user data, and the second position information generation Extraction means for extracting the auxiliary data from the replacement user data based on the position information generated by the means.
　本発明の第１の情報再生装置によれば、上述した本発明の第１の情報生成装置によって生成された置換ユーザデータが再生される。置換ユーザデータは、先ず復号手段において、誤り訂正符号を用いて復号される。これにより、意図的に埋め込まれた誤りである補助データは、置換前のユーザデータに戻される。また、記録の際などに発生した誤りに関しても、同様に訂正される。 According to the first information reproducing apparatus of the present invention, the replacement user data generated by the above-described first information generating apparatus of the present invention is reproduced. The replacement user data is first decoded by the decoding means using the error correction code. Thereby, the auxiliary data which is an intentionally embedded error is returned to the user data before replacement. Also, errors that occur during recording are corrected in the same manner.
　ユーザデータが復号されると、第２位置情報生成手段によって、復号されたユーザデータから位置情報が生成される。尚、第２位置情報生成手段は、上述した本発明の第１の情報生成装置における位置情報生成手段と同様に位置情報を生成する。言い換えれば、情報生成装置における位置情報生成手段と、情報再生手段における第２位置情報生成手段は、同一のものであってもよい。 When the user data is decoded, position information is generated from the decoded user data by the second position information generating means. The second position information generating means generates position information in the same manner as the position information generating means in the first information generating apparatus of the present invention described above. In other words, the position information generating means in the information generating device and the second position information generating means in the information reproducing means may be the same.
　位置情報が生成されると、抽出手段によって、置換ユーザデータから補助データが抽出される。即ち、本発明では、ユーザデータが再生できるような状態であれば、確実に補助データも再生することができる。尚、置換ユーザデータは、復号手段によって復号されるユーザデータとは別に、例えばメモリ等に記憶されており、抽出手段は記憶された置換ユーザデータから補助データを抽出する。 When the position information is generated, auxiliary data is extracted from the replacement user data by the extracting means. That is, according to the present invention, auxiliary data can be reliably reproduced as long as user data can be reproduced. The replacement user data is stored in, for example, a memory or the like separately from the user data decoded by the decoding unit, and the extraction unit extracts auxiliary data from the stored replacement user data.
　以上説明したように、本発明の第１の情報再生装置によれば、置換ユーザデータからユーザデータ及び補助データを確実に再生することができる。 As described above, according to the first information reproducing apparatus of the present invention, user data and auxiliary data can be reliably reproduced from replacement user data.
　本発明の第２の情報再生装置は上記課題を解決するために、上述した本発明の第２の情報生成装置によって生成された置換ユーザデータを再生する情報再生装置であって、前記置換ユーザデータから、前記変更補助データを抽出する抽出手段と、前記置換ユーザデータを、前記誤り訂正符号を用いて、前記ユーザデータに復号する復号手段と、前記変更情報を、前記復号されたユーザデータに基づいて生成する第２変更情報生成手段と、前記第２変更情報生成手段によって生成された前記変更情報に基づいて、前記変更補助データを前記補助データに再変更する再変更手段とを備える。 In order to solve the above-mentioned problem, the second information reproducing apparatus of the present invention is an information reproducing apparatus for reproducing the replacement user data generated by the above-described second information generating apparatus of the present invention, wherein the replacement user data From the extraction means for extracting the change auxiliary data, the decoding means for decoding the replacement user data into the user data using the error correction code, and the change information based on the decoded user data Second change information generating means to be generated, and re-change means for re-changing the change auxiliary data to the auxiliary data based on the change information generated by the second change information generating means.
　本発明の第２の情報再生装置によれば、上述した本発明の第２の情報生成装置によって生成された置換ユーザデータが再生される。置換ユーザデータは、先ず復号手段において、誤り訂正符号を用いて復号される。これにより、意図的に埋め込まれた誤りである変更補助データは、置換前のユーザデータに戻される。 According to the second information reproducing apparatus of the present invention, the replacement user data generated by the above-described second information generating apparatus of the present invention is reproduced. The replacement user data is first decoded by the decoding means using the error correction code. Thereby, the change auxiliary data which is an intentionally embedded error is returned to the user data before replacement.
　ユーザデータが復号されると、抽出手段は、例えば置換されたユーザデータの位置を示す位置情報等を用いて変更補助データを抽出する。位置情報は、ユーザデータとは別に記憶されている情報であってもよいし、ユーザデータを置換する前に予め設定されたものであってもよい。 When the user data is decrypted, the extraction means extracts the change auxiliary data using, for example, position information indicating the position of the replaced user data. The position information may be information stored separately from the user data, or may be set in advance before replacing the user data.
　また、復号前の置換ユーザデータと復号後のユーザデータとを互いに比較することで、変更補助データを抽出することもできる。即ち、復号によって、意図的な誤りである変更補助データが訂正されるということを利用して、変更補助データを抽出することができる。尚、置換ユーザデータは、復号手段によって復号されるユーザデータとは別に、例えばメモリ等に記憶されており、抽出手段は記憶された置換ユーザデータと復号されたユーザデータを互いに比較する。 Also, the change auxiliary data can be extracted by comparing the replacement user data before decryption with the user data after decryption. That is, the change auxiliary data can be extracted by utilizing the fact that the change auxiliary data, which is an intentional error, is corrected by decoding. The replacement user data is stored in, for example, a memory or the like separately from the user data decrypted by the decryption means, and the extraction means compares the stored replacement user data with the decrypted user data.
　また、復号されたユーザデータからは、第２変更情報生成手段によって、変更補助データを補助データに再変更するための変更情報が生成される。尚、第２変更情報生成手段は、上述した本発明の第２の情報生成装置における変更情報生成手段と同様に変更情報を生成する。言い換えれば、情報生成装置における変更情報生成手段と、情報再生手段における第２変更情報生成手段は、同一のものであってもよい。 Also, from the decrypted user data, change information for re-changing the change auxiliary data to auxiliary data is generated by the second change information generating means. The second change information generation means generates change information in the same manner as the change information generation means in the second information generation apparatus of the present invention described above. In other words, the change information generating means in the information generating device and the second change information generating means in the information reproducing means may be the same.
　変更情報が生成されると、再変更手段によって、変更補助データは補助データに再変更される。即ち、本発明では、ユーザデータが再生できるような状態であれば、確実に補助データも再生することができる。変更補助データは、例えば補助データを変更補助データへと変更する際とは逆の演算処理等が行われることによって補助データへと再変更される。 When the change information is generated, the change auxiliary data is changed again to auxiliary data by the re-change means. That is, according to the present invention, auxiliary data can be reliably reproduced as long as user data can be reproduced. The change auxiliary data is re-changed into auxiliary data, for example, by performing an arithmetic process or the like reverse to that when changing the auxiliary data to change auxiliary data.
　以上説明したように、本発明の第２の情報再生装置によれば、置換ユーザデータからユーザデータ及び補助データを確実に再生することができる。 As described above, according to the second information reproducing apparatus of the present invention, user data and auxiliary data can be reliably reproduced from the replacement user data.
　本発明の第１の情報生成方法は上記課題を解決するために、ユーザデータの一部を、前記ユーザデータに関連するデータであって、前記ユーザデータとは異なる用途で用いられる補助データに置換して、置換ユーザデータを生成する情報生成方法であって、前記ユーザデータに対して誤り訂正符号を付加して、符号化データを生成する符号化工程と、前記符号化データにおける前記補助データに置換されるデータの位置を示す位置情報を、前記ユーザデータに基づいて生成する位置情報生成工程と、前記符号化データの一部を、前記位置情報に基づいて前記補助データに置換して、前記置換ユーザデータを生成する置換工程とを備える。 In order to solve the above problems, a first information generation method of the present invention replaces a part of user data with auxiliary data that is related to the user data and is used for a different purpose from the user data. An information generation method for generating replacement user data, wherein an error correction code is added to the user data to generate encoded data, and the auxiliary data in the encoded data is added to the auxiliary data. A position information generation step for generating position information indicating the position of data to be replaced based on the user data; and a part of the encoded data is replaced with the auxiliary data based on the position information; A replacement step of generating replacement user data.
　本発明の第１の情報生成方法によれば、補助データが符号化データの一部と置換され、置換されたデータの位置を示す位置情報がユーザデータに基づいて生成されるので、上述した第１の情報生成装置と同様に、実践上の様々な不都合を回避しつつ、補助データを確実に再生可能な情報を生成することができる。 According to the first information generation method of the present invention, the auxiliary data is replaced with a part of the encoded data, and the position information indicating the position of the replaced data is generated based on the user data. As in the case of the first information generation apparatus, it is possible to generate information that can reliably reproduce the auxiliary data while avoiding various practical inconveniences.
　尚、本発明の第１の情報生成方法においても、上述した第１の情報生成装置と同様の各種態様をとることが可能である。 In the first information generation method of the present invention, it is possible to take various aspects similar to those of the first information generation apparatus described above.
　本発明の第２の情報生成方法は上記課題を解決するために、ユーザデータの一部を、前記ユーザデータに関連するデータであって、前記ユーザデータとは異なる用途で用いられる補助データに置換して、置換ユーザデータを生成する情報生成方法であって、前記ユーザデータに対して誤り訂正符号を付加して、符号化データを生成する符号化工程と、前記補助データを変更補助データに変更するための変更情報を、前記ユーザデータに基づいて生成する変更情報生成工程と、前記変更情報を用いて、前記補助データを変更補助データに変更する補助データ変更工程と、前記符号化データの一部を、前記変更補助データに置換して、前記置換ユーザデータを生成する置換工程とを備える。 In order to solve the above-described problem, the second information generation method of the present invention replaces part of user data with auxiliary data that is related to the user data and is used for a different purpose from the user data. An information generation method for generating replacement user data, wherein an error correction code is added to the user data to generate encoded data, and the auxiliary data is changed to change auxiliary data A change information generation step for generating change information to be changed based on the user data, an auxiliary data change step for changing the auxiliary data to change auxiliary data using the change information, and one of the encoded data And a replacement step of generating the replacement user data by replacing the portion with the change auxiliary data.
　本発明の第２の情報生成方法によれば、補助データが、ユーザデータに基づいて生成される変更情報に基づいて変更補助データへと変換されるため、上述した第２の情報生成装置と同様に、高いセキュリティを実現しつつ、補助データを確実に再生可能な情報を生成することができる。 According to the second information generation method of the present invention, the auxiliary data is converted into the change auxiliary data based on the change information generated based on the user data, so that it is the same as the second information generation device described above. In addition, it is possible to generate information that can reliably reproduce the auxiliary data while realizing high security.
　本発明の第１の情報再生方法は上記課題を解決するために、上述した本発明の第１の情報生成方法によって生成された置換ユーザデータを再生する情報再生方法であって、前記置換ユーザデータを、前記誤り訂正符号を用いて、前記ユーザデータに復号する復号工程と、前記位置情報を、前記復号されたユーザデータに基づいて生成する第２位置情報生成工程と、前記第２位置情報生成工程において生成された前記位置情報に基づいて、前記置換ユーザデータから前記補助データを抽出する抽出工程とを備える。 In order to solve the above problems, a first information reproduction method of the present invention is an information reproduction method of reproducing replacement user data generated by the above-described first information generation method of the present invention, wherein the replacement user data Is decoded into the user data using the error correction code, a second position information generation step is generated based on the decoded user data, and the second position information generation is performed. An extraction step of extracting the auxiliary data from the replacement user data based on the position information generated in the step.
　本発明の第１の情報再生方法によれば、ユーザデータに基づいて位置情報が生成されるため、上述した第１の情報再生装置と同様に、置換ユーザデータからユーザデータ及び補助データを確実に再生できる。 According to the first information reproducing method of the present invention, since the position information is generated based on the user data, the user data and the auxiliary data are reliably obtained from the replacement user data as in the first information reproducing apparatus described above. Can play.
　本発明の第２の情報再生方法は上記課題を解決するために、上述した本発明の第２の情報生成方法によって生成された置換ユーザデータを再生する情報再生方法であって、前記置換ユーザデータから、前記変更補助データを抽出する抽出工程と、前記置換ユーザデータを、前記誤り訂正符号を用いて、前記ユーザデータに復号する復号工程と、前記変更情報を、前記復号されたユーザデータに基づいて生成する第２変更情報生成工程と、前記第２変更情報生成工程において生成された前記変更情報に基づいて、前記変更補助データを前記補助データに再変更する再変更工程とを備える。 In order to solve the above problem, a second information reproduction method of the present invention is an information reproduction method of reproducing replacement user data generated by the above-described second information generation method of the present invention, wherein the replacement user data From the extraction step of extracting the change auxiliary data, the decoding step of decoding the replacement user data into the user data using the error correction code, and the change information based on the decoded user data A second change information generation step that is generated, and a re-change step that re-changes the change auxiliary data into the auxiliary data based on the change information generated in the second change information generation step.
　本発明の第２の情報再生方法によれば、ユーザデータに基づいて変更情報が生成されるため、上述した第２の情報再生装置と同様に、置換ユーザデータからユーザデータ及び補助データを確実に再生できる。 According to the second information reproducing method of the present invention, the change information is generated based on the user data, so that the user data and the auxiliary data are reliably obtained from the replacement user data as in the second information reproducing apparatus described above. Can play.
　本発明の作用及び他の利得は、次に説明する実施するための最良の形態から明らかにされる。 The operation and other advantages of the present invention will become apparent from the best mode for carrying out the invention described below.
第１実施形態に係る情報生成装置及び情報再生装置の構成を示すブロック図である。It is a block diagram which shows the structure of the information generation apparatus and information reproduction apparatus which concern on 1st Embodiment. 第１実施形態に係る情報生成装置及び情報再生装置の変形例を示すブロック図である。It is a block diagram which shows the modification of the information generation apparatus and information reproduction apparatus which concern on 1st Embodiment. 第１実施形態に係る情報生成装置の動作の流れを示すフローチャートである。It is a flowchart which shows the flow of operation | movement of the information generation apparatus which concerns on 1st Embodiment. 位置情報の生成方法について示す概念図である。It is a conceptual diagram shown about the production | generation method of position information. ユーザデータを補助データに置換する方法について示す概念図（その１）である。It is a conceptual diagram (the 1) shown about the method of replacing user data with auxiliary data. ユーザデータを補助データに置換する方法について示す概念図（その２）である。It is a conceptual diagram (the 2) shown about the method of replacing user data with auxiliary data. 第１実施形態に係る情報再生装置の動作の流れを示すフローチャートである。It is a flowchart which shows the flow of operation | movement of the information reproduction apparatus which concerns on 1st Embodiment. ユーザデータの復号及び位置情報の生成方法を示す概念図である。It is a conceptual diagram which shows the decoding method of user data, and the production | generation method of position information. 補助データの抽出及び復号方法を示す概念図である。It is a conceptual diagram which shows the extraction and decoding method of auxiliary data. 第２実施形態に係る情報生成装置及び情報再生装置の構成を示すブロック図である。It is a block diagram which shows the structure of the information generation apparatus and information reproduction apparatus which concern on 2nd Embodiment. 第３実施形態に係る情報生成装置及び情報再生装置の構成を示すブロック図である。It is a block diagram which shows the structure of the information generation apparatus and information reproduction apparatus which concern on 3rd Embodiment. 位置情報生成部の構成を示すブロック図（その１）である。It is a block diagram (the 1) which shows the structure of a position information generation part. 位置情報生成部の構成を示すブロック図（その２）である。It is a block diagram (the 2) which shows the structure of a position information generation part. 位置情報生成部の構成を示すブロック図（その３）である。It is a block diagram (the 3) which shows the structure of a position information generation part. 第４実施形態に係る情報生成装置における、位置情報の生成及び補助データの置換方法を示す概念図である。It is a conceptual diagram which shows the production | generation method of positional information and the replacement method of auxiliary data in the information generation apparatus which concerns on 4th Embodiment. 第４実施形態に係る情報再生装置における、補助データの再生方法を示す概念図である。It is a conceptual diagram which shows the reproducing method of auxiliary data in the information reproducing | regenerating apparatus which concerns on 4th Embodiment. 第５実施形態に係る情報生成装置及び情報再生装置の構成を示すブロック図である。It is a block diagram which shows the structure of the information generation apparatus and information reproduction apparatus which concern on 5th Embodiment. 第５実施形態に係る情報生成装置及び情報再生装置の変形例を示すブロック図である。It is a block diagram which shows the modification of the information generation apparatus and information reproduction apparatus which concern on 5th Embodiment. 第５実施形態に係る情報生成装置の動作の流れを示すフローチャートである。It is a flowchart which shows the flow of operation | movement of the information generation apparatus which concerns on 5th Embodiment. 変更情報の生成方法について示す概念図である。It is a conceptual diagram shown about the production | generation method of change information. 変更情報を用いた補助データの変更方法について示す概念図である。It is a conceptual diagram shown about the change method of auxiliary data using change information. 第５実施形態に係る情報再生装置の動作の流れを示すフローチャートである。It is a flowchart which shows the flow of operation | movement of the information reproduction apparatus which concerns on 5th Embodiment. ユーザデータの復号及び変更情報の生成方法を示す概念図である。It is a conceptual diagram which shows the decoding method of user data, and the production | generation method of change information. 補助データの抽出及び再変更、並びに復号方法を示す概念図である。It is a conceptual diagram which shows extraction and re-change of auxiliary data, and a decoding method. 符号化部から出力されるデータを示す概念図（その１）である。It is a conceptual diagram (the 1) which shows the data output from an encoding part. 第２符号化部から出力されるデータを示す概念図である。It is a conceptual diagram which shows the data output from a 2nd encoding part. 補助データの分割について示す概念図（その１）である。It is a conceptual diagram (the 1) shown about the division | segmentation of auxiliary data. 補助データの分割について示す概念図（その２）である。It is a conceptual diagram (the 2) shown about the division | segmentation of auxiliary data. 符号化部から出力されるデータを示す概念図（その２）である。It is a conceptual diagram (the 2) which shows the data output from an encoding part.
符号の説明Explanation of symbols
　１００　情報生成装置
　１１０　符号化部
　１２０　位置情報生成部
　１２１　生成部
　１２２　位置情報暗号化部
　１２３　ユーザデータ暗号化部
　１２４　ＨＭＡＣ処理部
　１３０　第２符号化部
　１４０　置換部
　１５０　変調部
　１６０　書き込み部
　１７０　変更情報生成部
　１８０　変更部
　２００　情報再生装置
　２１０　読み出し部
　２２０　復調部
　２３０　復号部
　２４０　第２位置情報生成部
　２５０　抽出部
　２６０　第２復号部
　２７０　第２変更情報生成部
　２８０　再変更部
　３００　ホログラフィックメモリ
　４００　通信ケーブル
　５１０　暗号化部
　５２０　第３復号部 DESCRIPTION OF SYMBOLS 100 Information generation apparatus 110 Encoding part 120 Location information generation part 121 Generation part 122 Position information encryption part 123 User data encryption part 124 HMAC processing part 130 2nd encoding part 140 Replacement part 150 Modulation part 160 Writing part 170 Change information Generating unit 180 Changing unit 200 Information reproducing device 210 Reading unit 220 Demodulating unit 230 Decoding unit 240 Second position information generating unit 250 Extracting unit 260 Second decoding unit 270 Second change information generating unit 280 Rechanging unit 300 Holographic memory 400 Communication Cable 510 Encryption unit 520 Third decryption unit
　以下では、本発明の実施形態について図を参照しつつ説明する。尚、以下では本発明の情報生成装置及び情報再生装置を用いて、記録媒体であるホログラフィックメモリに対して情報の記録及び再生を行う場合を例にとり説明する。 Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, a case where information is recorded and reproduced with respect to a holographic memory as a recording medium using the information generating apparatus and the information reproducing apparatus of the present invention will be described.
　＜第１実施形態＞
　先ず、第１実施形態に係る情報生成装置の構成について、図１及び図２を参照して説明する。ここに図１は、第１実施形態に係る情報生成装置及び情報再生装置の構成を示すブロック図であり、図２は、第１実施形態に係る情報生成装置及び情報再生装置の変形例を示すブロック図である。 <First Embodiment>
First, the configuration of the information generation apparatus according to the first embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is a block diagram showing the configuration of the information generating apparatus and the information reproducing apparatus according to the first embodiment, and FIG. 2 shows a modification of the information generating apparatus and the information reproducing apparatus according to the first embodiment. It is a block diagram.
　図１において、第１実施形態に係る情報生成装置１００は、符号化部１１０と、位置情報生成部１２０と、第２符号化部１３０と、置換部１４０と、変調部１５０と、書き込み部１６０とを備えて構成されている。 In FIG. 1, the information generation apparatus 100 according to the first embodiment includes an encoding unit 110, a position information generation unit 120, a second encoding unit 130, a replacement unit 140, a modulation unit 150, and a writing unit 160. And is configured.
　符号化部１１０は、本発明の「符号化手段」の一例であり、入力されたユーザデータ（例えば、映像ファイルや音楽ファイル、文書ファイルなどの記録すべきデータ）に対して誤り訂正符号を付加する。 The encoding unit 110 is an example of the “encoding unit” of the present invention, and adds an error correction code to input user data (for example, data to be recorded such as a video file, a music file, a document file). To do.
　位置情報生成部１２０は、本発明の「位置情報生成手段」の一例であり、入力されたユーザデータから、後述する置換部１４０において置換するデータの位置を示す位置情報を生成する。位置情報は、ユーザ情報から一意的に求められるような情報である。 The position information generation unit 120 is an example of the “position information generation unit” of the present invention, and generates position information indicating the position of data to be replaced in the replacement unit 140 described later from the input user data. The position information is information that is uniquely obtained from the user information.
　第２符号化部１３０は、本発明の「補助符号化手段」の一例であり、入力された補助データに対して誤り訂正符号を付加する。補助データは、ユーザデータに関連する補助的なデータであり、ユーザデータとは異なる用途で用いられる。補助データの例として、ユーザデータの属性、ファイル名前及び管理番号等を示すデータや、分割されたユーザデータの分割位置を示すデータ、ユーザデータが不正にコピーされたデータであるか否かを識別するためのデータ等が挙げられる。尚、符号化部１１０及び第２符号化部１３０を同一の演算回路等から構成するようにしてもよい。 The second encoding unit 130 is an example of the “auxiliary encoding unit” of the present invention, and adds an error correction code to the input auxiliary data. The auxiliary data is auxiliary data related to the user data, and is used for a purpose different from the user data. As an example of auxiliary data, data indicating user data attributes, file name, management number, etc., data indicating the division position of divided user data, and whether or not user data is illegally copied data Data and the like. Note that the encoding unit 110 and the second encoding unit 130 may be configured by the same arithmetic circuit or the like.
　置換部１４０は、本発明の「置換手段」の一例であり、符号化部１１０において符号化されたユーザデータの一部を、第２符号化部１３０において符号化された補助データと置換する。この際、置換されるユーザデータの位置は、位置情報生成部１２０において生成された位置情報に基づいている。 The replacement unit 140 is an example of the “replacement unit” of the present invention, and replaces part of the user data encoded by the encoding unit 110 with auxiliary data encoded by the second encoding unit 130. At this time, the position of the user data to be replaced is based on the position information generated by the position information generation unit 120.
　変調部１５０は、置換部１４０において置換されたユーザデータを記録するのに適切な方式のデータへと変調する。本実施形態のようにホログラフィックメモリ３００に対して情報を記録する場合には、例えば２ビットのデータを４つの画素で示す（２，４）変調や、６ビットのデータを９つの画素で示す（６，９）変調等が用いられる。 The modulation unit 150 modulates the user data replaced by the replacement unit 140 into data of an appropriate system for recording. When information is recorded in the holographic memory 300 as in the present embodiment, for example, (2, 4) modulation in which 2 bits of data are indicated by 4 pixels and 6 bits of data are indicated by 9 pixels. (6, 9) modulation or the like is used.
　書き込み部１６０は、例えば光源やレンズ等を含んで構成されており、光源から出射されたレーザ光をレンズで集光してホログラフィックメモリ３００に照射し、干渉縞としてユーザデータを記憶する。 The writing unit 160 includes, for example, a light source, a lens, and the like, condenses the laser light emitted from the light source with the lens, irradiates the holographic memory 300, and stores user data as interference fringes.
　図２において、第１実施形態に係る情報生成装置及び情報再生装置は、上述した情報の記録以外に、例えば通信によって情報をやり取りする場合にも利用することが可能である。このような場合は、変調部１５０において通信用に変調されたユーザデータが、例えば図に示すような通信ケーブル４００を介して電気信号として伝送される。情報生成装置及び情報再生装置は、電気信号の変調や復調に加えて、同期信号を用いた情報位置の特定や管理情報の処理等を行う。 In FIG. 2, the information generating apparatus and the information reproducing apparatus according to the first embodiment can be used not only for recording information but also for exchanging information by communication, for example. In such a case, user data modulated for communication in the modulation unit 150 is transmitted as an electrical signal via a communication cable 400 as shown in the figure, for example. In addition to modulation and demodulation of electrical signals, the information generation device and the information reproduction device perform information position specification, management information processing, and the like using a synchronization signal.
　続いて、第１実施形態に係る情報生成装置の動作について、図１に加えて、図３から図６を参照して説明する。ここに図３は、第１実施形態に係る情報生成装置の動作の流れを示すフローチャートである。また図４は、位置情報の生成方法について示す概念図であり、図５及び図６は夫々、ユーザデータを補助データに置換する方法について示す概念図である。 Subsequently, the operation of the information generating apparatus according to the first embodiment will be described with reference to FIGS. 3 to 6 in addition to FIG. FIG. 3 is a flowchart showing an operation flow of the information generating apparatus according to the first embodiment. FIG. 4 is a conceptual diagram illustrating a method for generating position information, and FIGS. 5 and 6 are conceptual diagrams illustrating a method for replacing user data with auxiliary data.
　図１及び図３において、第１実施形態に係る情報生成装置１００の動作時には、先ず符号化部１１０にユーザデータが入力される。符号化部１１０は、入力されたユーザデータに対して誤り訂正符号を付加する（ステップＳ１１）。これにより、ユーザデータの一部に誤りが生じた場合であっても、誤り訂正符号を用いて正しいデータを修復することが可能となる。図４に示すように、ユーザデータに対する誤り訂正符号（Ｃ１～Ｃ４）は、典型的には、ユーザデータ（Ｕ１～Ｕ８）の最後の部分に付加される。但し、インターリーブ等によって、各データの配置が並び替えられてもよい。 1 and 3, when the information generating apparatus 100 according to the first embodiment operates, first, user data is input to the encoding unit 110. The encoding unit 110 adds an error correction code to the input user data (step S11). As a result, even if an error occurs in a part of user data, correct data can be restored using the error correction code. As shown in FIG. 4, error correction codes (C1 to C4) for user data are typically added to the last part of user data (U1 to U8). However, the arrangement of each data may be rearranged by interleaving or the like.
　他方で、第２符号化部１３０には補助データが入力される。第２符号化部１３０は、補助データに対し誤り訂正符号を付加する（ステップＳ１２）。これにより、補助データも、ユーザデータと同様に誤り訂正能力を有することになる。図５に示すように、補助データに対する誤り訂正符号（Ｅ１）は、典型的には、補助データ（Ａ１及びＡ２）の最後の部分に付加される。但し、上述したユーザデータと同様に、インターリーブ等によって、各データの配置が並び替えられてもよい。 On the other hand, auxiliary data is input to the second encoding unit 130. The second encoding unit 130 adds an error correction code to the auxiliary data (step S12). As a result, the auxiliary data also has an error correction capability like the user data. As shown in FIG. 5, the error correction code (E1) for the auxiliary data is typically added to the last part of the auxiliary data (A1 and A2). However, similarly to the user data described above, the arrangement of each data may be rearranged by interleaving or the like.
　ユーザデータは、上述した符号化部１１０に加えて、位置情報生成部１２０にも入力されている。位置情報生成部１２０は、入力されたユーザデータに基づいて、ユーザデータの一部を補助データに置換する際に置換されるデータの位置を示す位置情報を生成する（ステップＳ１３）。位置情報は、例えばハッシュ関数により生成されるハッシュ値を用いることができ、ハッシュ関数にＳＨＡ－１（Secure Hash Algorithm 1）を用いる場合には、任意長の入力値（即ち、ユーザデータ）に対して、１６０ビットの出力値（即ち、位置情報）が得られる。尚、位置情報は、ハッシュ値のように、ユーザデータから一意的に求められる情報であれば、直接的にデータの位置を示すような情報でなくともよい。このような場合は、例えば位置情報が有する値と、置換するデータの位置とを対応させるような法則を予め設定しておくことで、置換されるデータの位置が示される。 User data is input to the position information generation unit 120 in addition to the encoding unit 110 described above. The position information generation unit 120 generates position information indicating the position of data to be replaced when a part of the user data is replaced with auxiliary data based on the input user data (step S13). As the position information, for example, a hash value generated by a hash function can be used. When SHA-1 (Secure Hash Algorithm 1) is used for the hash function, an arbitrary length input value (that is, user data) is used. Thus, a 160-bit output value (that is, position information) is obtained. Note that the position information may not be information that directly indicates the position of the data as long as it is information uniquely obtained from the user data, such as a hash value. In such a case, for example, the position of the data to be replaced is indicated by setting in advance a rule that associates the value of the position information with the position of the data to be replaced.
　位置情報が生成されると、置換部１４０は、ユーザデータの一部を補助データへと置換する（ステップＳ１４）。置換部１４０は、位置情報生成部１２０によって生成された位置情報に基づいて、ユーザデータを補助データに置換する。尚、ユーザデータは、誤り訂正符号を付加された後に補助データと置換されることとなるため、置換された補助データは意図的な誤りとして扱われる。 When the position information is generated, the replacement unit 140 replaces part of the user data with auxiliary data (step S14). The replacement unit 140 replaces user data with auxiliary data based on the position information generated by the position information generation unit 120. Since user data is replaced with auxiliary data after an error correction code is added, the replaced auxiliary data is treated as an intentional error.
　ここで図４に示すように、位置情報生成部１２０によって、ユーザデータ（Ｕ１～Ｕ８）から、７，２，５，６，８，・・・といった位置情報が生成されているとする。また図５に示すように、ユーザデータは、４つのデータ毎に第１ブロックから第３ブロックの３つのブロックに分けられており、各ブロック中のデータには０～３のポジション番号が付与されているとする。尚、ここでは後述するように各ブロックに対して補助データを１つずつ置換するため、ユーザデータにおけるブロックの数は、置換する補助データの数（即ち、ここではＡ１、Ａ２及びＥ１の３つ）と同じ、或いはそれ以上であることが望ましい。 Here, as shown in FIG. 4, it is assumed that position information such as 7, 2, 5, 6, 8,... Has been generated from the user data (U1 to U8) by the position information generation unit 120. Further, as shown in FIG. 5, the user data is divided into three blocks from the first block to the third block every four data, and position numbers 0 to 3 are assigned to the data in each block. Suppose that Here, as will be described later, since auxiliary data is replaced one by one for each block, the number of blocks in the user data is the number of auxiliary data to be replaced (that is, three of A1, A2, and E1 here). ) Or more.
　また、補助データの情報量が多く、例えば位置情報として出力されたハッシュ関数の出力値の数より補助データの値の数の方が多い場合には、位置情報を示すための値が不足してしまう。このような場合には、ハッシュ関数の出力を更にハッシュ関数に入力した値（即ち、ハッシュ値のハッシュ値）を生成することで対応することが可能である。 Also, when the amount of auxiliary data is large, for example, when the number of auxiliary data values is larger than the number of output values of the hash function output as position information, the value for indicating the position information is insufficient. End up. Such a case can be dealt with by generating a value obtained by further inputting the output of the hash function into the hash function (that is, a hash value of the hash value).
　置換部１４０には、予め位置情報の各値をブロック長（即ち、ここでは“４”）で割った余りが示すポジションのユーザデータと、補助データとを置換するという法則が記憶されている。尚、位置情報は、先頭の値から第１ブロック、第２ブロック、第３ブロックに夫々対応しており、ここでは４つ目以降の値は用いない。但し、４つ目以降の値を用いるようにしてもよい。 The replacement unit 140 stores a rule that the user data of the position indicated by the remainder obtained by dividing each value of the position information by the block length (in this case, “4”) and the auxiliary data are replaced. The position information corresponds to the first block, the second block, and the third block from the top value, and the fourth and subsequent values are not used here. However, the fourth and subsequent values may be used.
　図５において、上述した法則により、第１ブロックについては、位置情報の先頭の値である“７”を４で割った余りが“３”となるので、補助データＡ１が第１ブロックのポジション３のユーザデータＵ４と置換される。第２ブロックについては、位置情報の２番目の値である“２”を４で割った余りが“２”となるので、補助データＡ２が第２ブロックのポジション２のユーザデータＵ７と置換される。第３ブロックについては、位置情報の３番目の値である“５”を４で割った余りが“１”となるので、補助データに付加された誤り訂正符号Ｅ１が第３ブロックのポジション１の誤り訂正符号Ｃ２と置換される。以上のように置換すれば、比較的容易に、且つユーザデータに対して、均等に補助データを埋め込むことができる。 In FIG. 5, according to the above-described rule, for the first block, the remainder obtained by dividing “7”, which is the first value of the position information, by 4 is “3”, so that the auxiliary data A1 is the position 3 of the first block. Is replaced with user data U4. For the second block, the remainder of dividing the second position information value “2” by 4 is “2”, so the auxiliary data A2 is replaced with the user data U7 at position 2 of the second block. . For the third block, the remainder of dividing the third value “5” of the position information by 4 is “1”, so the error correction code E1 added to the auxiliary data is the position 1 of the third block. Replaced with error correction code C2. By replacing as described above, auxiliary data can be embedded relatively easily and evenly in user data.
　上述した置換方法はあくまで一例であり、例えばデータが置換されないブロックが存在するようにしてもよい。具体的には、位置情報の各値をブロック長である“４”で割った余りに応じて補助データを置換するという法則に代えて、余りが０又は３の場合には対応するブロックにおける置換を行わず、余りが２の場合にポジション０及びポジション２の置換を行い、余りが１の場合にポジション１を置換するという法則を用いて置換する。 The replacement method described above is merely an example. For example, there may be a block in which data is not replaced. Specifically, instead of the rule of replacing auxiliary data according to the remainder obtained by dividing each value of the position information by “4” that is the block length, if the remainder is 0 or 3, replacement in the corresponding block is performed. Without replacement, the replacement of position 0 and position 2 is performed when the remainder is 2, and the replacement is performed using the rule of replacing position 1 when the remainder is 1.
　図６において、上述した法則によれば、第１ブロックについては、位置情報の先頭の値である“７”を４で割った余りが“３”となるので置換されない。第２ブロックについては、位置情報の２番目の値である“２”を４で割った余りが“２”となるので、補助データＡ１及びＡ２が第２ブロックのポジション０のユーザデータＵ５及びポジション２のユーザデータＵ７と夫々置換される。第３ブロックについては、位置情報の３番目の値である“５”を４で割った余りが“１”となるので、補助データに付加された誤り訂正符号Ｅ１が第３ブロックのポジション１の誤り訂正符号Ｃ２と置換される。 In FIG. 6, according to the above-mentioned rule, the first block is not replaced because the remainder of dividing the first value “7” of the position information by 4 becomes “3”. For the second block, the remainder obtained by dividing “2”, which is the second value of the position information, by 4 is “2”, so that the auxiliary data A1 and A2 are the user data U5 and the position of the position 0 of the second block. 2 is replaced with the user data U7. For the third block, the remainder of dividing the third value “5” of the position information by 4 is “1”, so the error correction code E1 added to the auxiliary data is the position 1 of the third block. Replaced with error correction code C2.
　ブロックにおける補助データが置換される位置を自由に変更することができれば、例えば記録媒体の特定の場所や通信路の特定のタイミングに傷やノイズ等の誤りが生じやすいことが判明している場合に、該当するブロック内にあるシンボルを補助データで置換しないようにする、或いは置換するシンボル数を少なくすることが可能である。これにより、補助データが誤って抽出されてしまう可能性を低減することができる。 If the position where auxiliary data in the block is replaced can be freely changed, for example, it has been found that errors such as scratches and noise are likely to occur at a specific location of the recording medium and a specific timing of the communication path. It is possible not to replace the symbols in the corresponding block with auxiliary data, or to reduce the number of symbols to be replaced. Thereby, possibility that auxiliary data will be extracted accidentally can be reduced.
　以上のように、置換方法は位置情報を用いるものであれば特に限定されず、後述する本実施形態に係る情報生成装置の効果を適切に発揮することが可能である。また、複数の置換方法を予め設定しておき、特定のタイミングで法則を切り換えて使用することも可能である。尚、この効果については、後述する本実施形態に係る情報再生装置の説明において詳述する。 As described above, the replacement method is not particularly limited as long as it uses position information, and it is possible to appropriately exert the effect of the information generation apparatus according to the present embodiment described later. It is also possible to set a plurality of replacement methods in advance and switch the rules at specific timings. This effect will be described in detail in the description of the information reproducing apparatus according to the present embodiment described later.
　図１及び図３に戻り、ユーザデータの一部が補助データに置換されると、変調部１５０は、ユーザデータを記録に適した方式に変調する（ステップＳ１５）。書き込み部１６０は、変調したユーザデータをホログラフィックメモリ３００に記録する（ステップＳ１６）。尚、本実施形態に係る情報生成装置では、置換した補助データの位置を示す位置情報はホログラフィックメモリ３００には記録されない。また他の記録媒体にも記録する必要はない。よって、ここで記録されるデータの大きさは、記録すべきユーザデータの大きさと同じで済む。 1 and 3, when a part of the user data is replaced with the auxiliary data, the modulation unit 150 modulates the user data into a method suitable for recording (step S15). The writing unit 160 records the modulated user data in the holographic memory 300 (step S16). In the information generating apparatus according to this embodiment, position information indicating the position of the replaced auxiliary data is not recorded in the holographic memory 300. Moreover, it is not necessary to record on another recording medium. Therefore, the size of the data recorded here is the same as the size of the user data to be recorded.
　次に、第１実施形態に係る情報再生装置の構成について、再び図１及び図２を参照して説明する。 Next, the configuration of the information reproducing apparatus according to the first embodiment will be described with reference to FIGS. 1 and 2 again.
　図１において、第１実施形態に係る情報再生装置２００は、読み出し部２１０と、復調部２２０と、復号部２３０と、第２位置情報生成部２４０と、抽出部２５０と、第２復号部２６０とを備えて構成されている。 In FIG. 1, the information reproducing apparatus 200 according to the first embodiment includes a reading unit 210, a demodulating unit 220, a decoding unit 230, a second position information generating unit 240, an extracting unit 250, and a second decoding unit 260. And is configured.
　読み出し部２１０は、例えば発光部、レンズ及び受光素子を備えて構成されており、ホログラフィックメモリ３００にレーザ光を照射して得られる像を、受光素子によって検出し、検出された像からユーザデータを再生する。 The reading unit 210 includes, for example, a light emitting unit, a lens, and a light receiving element. The reading unit 210 detects an image obtained by irradiating the holographic memory 300 with laser light by the light receiving element, and user data is detected from the detected image. Play.
　復調部２２０は、情報生成装置１００における変調部１５０によって変調したユーザデータを元の状態へと復調する。即ち、変調部１５０とは逆の処理を行う。 The demodulator 220 demodulates the user data modulated by the modulator 150 in the information generation apparatus 100 to the original state. That is, the reverse process of the modulation unit 150 is performed.
　復号部２３０は、本発明の「復号手段」の一例であり、ユーザデータに付加された誤り訂正符号を用いて、ユーザデータに含まれる誤りを訂正する。 The decoding unit 230 is an example of the “decoding unit” of the present invention, and corrects an error included in user data using an error correction code added to the user data.
　第２位置情報生成部２４０は、本発明の「第２位置情報生成手段」の一例であり、復号部２３０において復号されたユーザデータ（即ち、誤りが訂正されたユーザデータ）から、情報生成装置１００における位置情報生成部１２０と同様に位置情報を生成する。尚、位置情報生成部１２０を第２位置情報生成部２４０として用いることもできる。 The second position information generation unit 240 is an example of the “second position information generation unit” in the present invention, and the information generation apparatus uses the user data decoded by the decoding unit 230 (that is, user data whose error is corrected). The position information is generated in the same manner as the position information generation unit 120 in 100. The position information generation unit 120 can also be used as the second position information generation unit 240.
　抽出部２５０は、本発明の「抽出手段」の一例であり、復号前のユーザデータ（即ち、補助データが意図的な誤りとして含まれているユーザデータ）から、第２位置情報生成部２４０において生成された位置情報を用いて、補助データを抽出する。 The extraction unit 250 is an example of the “extraction unit” of the present invention, and the second position information generation unit 240 uses user data before decoding (that is, user data in which auxiliary data is included as an intentional error). Auxiliary data is extracted using the generated position information.
　第２復号部２６０は、抽出された補助データに付加されている誤り訂正符号を用いて、補助データに含まれる誤りを訂正する。 The second decoding unit 260 corrects an error included in the auxiliary data by using an error correction code added to the extracted auxiliary data.
　尚、本実施形態に係る情報再生装置を、図２に示すような通信に用いる場合には、通信ケーブル４００を介して伝送されたデータが、復調部２２０に入力される。 When the information reproducing apparatus according to the present embodiment is used for communication as shown in FIG. 2, data transmitted via the communication cable 400 is input to the demodulation unit 220.
　続いて、第１実施形態に係る情報再生装置の動作について、図１に加えて、図７から図９を参照して説明する。ここに図７は、第１実施形態に係る情報再生装置の動作の流れを示すフローチャートである。また図８は、ユーザデータの復号及び位置情報の生成方法を示す概念図であり、図９は、補助データの抽出及び復号方法を示す概念図である。 Subsequently, the operation of the information reproducing apparatus according to the first embodiment will be described with reference to FIGS. 7 to 9 in addition to FIG. FIG. 7 is a flowchart showing an operation flow of the information reproducing apparatus according to the first embodiment. FIG. 8 is a conceptual diagram illustrating a method for decoding user data and generating position information. FIG. 9 is a conceptual diagram illustrating a method for extracting and decoding auxiliary data.
　図１及び図７において、本実施形態に係る情報再生装置２００の動作時には、先ず読み出し部２１０が、ホログラフィックメモリ３００に記録されたユーザデータを読み出す（ステップＳ２１）。続いて、復調部２２０が、読み出されたユーザデータを変調前の状態に復調する（ステップＳ２２）。 1 and 7, when the information reproducing apparatus 200 according to the present embodiment operates, the reading unit 210 first reads out user data recorded in the holographic memory 300 (step S21). Subsequently, the demodulator 220 demodulates the read user data to a state before modulation (step S22).
　ユーザデータが復調されると、復号部２３０は、ユーザデータに付加されている誤り訂正符号を用いて、ユーザデータに含まれる誤りを訂正する（ステップＳ２３）。この際、情報生成装置１００における置換部１４０によってユーザデータの一部と置換された補助データは、誤りとして訂正される。即ち、補助データは置換前のユーザデータとされる。復号されたユーザデータは、再生結果として外部に出力されると共に、第２位置情報生成部２４０に対しても出力される。第２位置情報生成部２４０は、復号されたユーザデータを用いて位置情報を生成する（ステップＳ２４）。 When the user data is demodulated, the decoding unit 230 corrects the error included in the user data using the error correction code added to the user data (step S23). At this time, the auxiliary data replaced with part of the user data by the replacement unit 140 in the information generating apparatus 100 is corrected as an error. That is, the auxiliary data is user data before replacement. The decrypted user data is output to the outside as a reproduction result and also output to the second position information generation unit 240. The second position information generation unit 240 generates position information using the decoded user data (step S24).
　図８において、読み出し部２１０によって読み出された際のユーザデータ（Ｄ１～Ｄ１２）には、意図的な誤りである補助データに加えて、ホログラフィックメモリ３００における傷や、記録及び再生時のノイズ等によって、いくつかの誤りが含まれている。復号部２３０は、このような誤りを含んだユーザデータを復号し、置換前のユーザデータ（Ｕ１～Ｕ８）とする。ユーザデータは、情報生成装置１００における位置情報生成部１２０が用いたユーザデータと同一のデータであるので、第２位置情報生成部２４０において生成される位置情報は、位置情報生成部１２０において生成された位置情報と同一のものとなる。このように、ユーザデータが復号できるのであれば、第２位置情報生成部２４０において再び同一の位置情報を生成することができる。よって、位置情報生成部１２０において生成した位置情報を、ホログラフィックメモリ３００や別の記録媒体等に記録しておく必要がない。 In FIG. 8, user data (D1 to D12) read by the reading unit 210 includes scratches in the holographic memory 300 and noise during recording and reproduction, in addition to auxiliary data that is an intentional error. Etc., some errors are included. The decoding unit 230 decodes the user data including such an error and uses it as user data (U1 to U8) before replacement. Since the user data is the same data as the user data used by the position information generation unit 120 in the information generation apparatus 100, the position information generated in the second position information generation unit 240 is generated in the position information generation unit 120. It becomes the same as the position information. As described above, if the user data can be decoded, the second position information generation unit 240 can generate the same position information again. Therefore, it is not necessary to record the position information generated by the position information generation unit 120 in the holographic memory 300 or another recording medium.
　図１及び図７に戻り、第２位置情報生成部２４０において生成された位置情報は、抽出部２５０に出力される。また、抽出部２５０には、復号部２３０において復号される前のユーザデータも出力されている。抽出部２５０は、復号前のユーザデータから、位置情報に基づいてデータを抽出する（ステップＳ２５）。 1 and 7, the position information generated in the second position information generation unit 240 is output to the extraction unit 250. Further, user data before being decoded by the decoding unit 230 is also output to the extraction unit 250. The extraction unit 250 extracts data from the user data before decoding based on the position information (step S25).
　図９において、上述したように、第２位置情報生成部２４０において生成される位置情報は、位置情報生成部１２０において生成された位置情報と同一のもの（７，２，５，６，８，・・・）であるので、置換部１４０において置換する場合の同様の法則に基づけば、確実に補助データを抽出することができる。具体的には、第１ブロックについては、位置情報の先頭の値である“７”を４で割った余りが“３”となるので、第１ブロックのポジション３からユーザデータＤ４が抽出される。第２ブロックについては、位置情報の２番目の値である“２”を４で割った余りが“２”となるので、第２ブロックのポジション２からユーザデータＤ７が抽出される。第３ブロックについては、位置情報の３番目の値である“５”を４で割った余りが“１”となるので、第３ブロックのポジション１からユーザデータＤ１０が抽出される。 9, as described above, the position information generated by the second position information generation unit 240 is the same as the position information generated by the position information generation unit 120 (7, 2, 5, 6, 8, ..)), The auxiliary data can be reliably extracted based on the same rule when the replacement unit 140 performs the replacement. Specifically, for the first block, since the remainder obtained by dividing “7”, which is the first value of the position information, by 4 is “3”, user data D4 is extracted from position 3 of the first block. . For the second block, the remainder obtained by dividing “2”, which is the second value of the position information, by 4 is “2”. Therefore, user data D7 is extracted from position 2 of the second block. For the third block, the remainder of dividing the third value “5” of the position information by 4 is “1”, so user data D10 is extracted from position 1 of the third block.
　抽出された補助データ（Ｄ４、Ｄ７及びＤ１０）は、第２復号部において誤りが訂正され、符号化前の補助データ（Ａ１及びＡ２）に復号される（ステップＳ２６）。復号された補助データは、再生結果として外部に出力される。 In the extracted auxiliary data (D4, D7, and D10), the second decoding unit corrects the error and decodes the auxiliary data (A1 and A2) before encoding (step S26). The decoded auxiliary data is output to the outside as a reproduction result.
　以上説明したように、第１実施形態に係る情報生成装置及び情報再生装置によれば、記録すべき情報が増大してしまうことを防止しつつ、確実に補助データを再生することが可能である。例えば補助データが不正ディスクを検出するための識別データとして、ユーザデータと共に記録媒体に記録される場合を考えると、仮に補助データが傷などに起因して再生できなくなれば、不正ディスクの検出ができなくなる。よって、補助データが再生できなくなることで、ユーザデータの再生まで不可能となってしまう或いは不正ディスクかもしれないディスクを再生せざるを得ないおそれがある。第１実施形態に係る情報生成装置及び情報再生装置によれば、このような実践上の不都合を好適に回避することが可能である。 As described above, according to the information generating apparatus and the information reproducing apparatus according to the first embodiment, it is possible to reliably reproduce auxiliary data while preventing an increase in information to be recorded. . For example, considering the case where auxiliary data is recorded on a recording medium together with user data as identification data for detecting an illegal disk, if the auxiliary data cannot be reproduced due to a scratch or the like, the illegal disk can be detected. Disappear. Therefore, since the auxiliary data cannot be reproduced, there is a possibility that the reproduction of the user data becomes impossible or a disc that may be an illegal disc must be reproduced. According to the information generating apparatus and the information reproducing apparatus according to the first embodiment, it is possible to preferably avoid such practical inconveniences.
　＜第２実施形態＞
　次に、第２実施形態に係る情報生成装置及び情報再生装置について、図１０を参照して説明する。ここに図１０は、第２実施形態に係る情報生成装置及び情報再生装置の構成を示すブロック図である。尚、第２実施形態は、上述した第１実施形態と比べて、ユーザデータが暗号化される点が異なり、その他の構成や動作等は概ね同じである。よって、ここでは第１実施形態と異なる部分について詳細に説明し、他の重複する部分については適宜説明を省略する。また図１０では、情報生成装置１００及び情報再生装置２００の各構成要素が上述した第１実施形態と同一であるため、詳細な図示を省略している。 <Second Embodiment>
Next, an information generating apparatus and an information reproducing apparatus according to the second embodiment will be described with reference to FIG. FIG. 10 is a block diagram showing the configuration of the information generating device and the information reproducing device according to the second embodiment. The second embodiment differs from the first embodiment described above in that user data is encrypted, and other configurations and operations are generally the same. Therefore, a different part from 1st Embodiment is demonstrated in detail here, and description is abbreviate | omitted suitably about another overlapping part. In FIG. 10, the components of the information generation device 100 and the information reproduction device 200 are the same as those in the first embodiment described above, and thus detailed illustration is omitted.
　図１０において、第２実施形態に係る情報生成装置１００には、暗号化部５１０によって暗号化されたユーザデータが入力される。よって、ユーザデータのセキュリティを向上させることが可能である。 In FIG. 10, the user data encrypted by the encryption unit 510 is input to the information generating apparatus 100 according to the second embodiment. Therefore, it is possible to improve the security of user data.
　暗号化部５１０におけるユーザデータの暗号化は、鍵情報を用いて行われる。そして、ここで用いられた鍵情報は、情報生成装置１００に補助データとして入力される。よって、第２実施形態では、ユーザデータに対して鍵情報が意図的な誤りとして埋め込まれた状態で記録が行われる。従って、鍵情報を記録するためにデータの大きさが増加してしまうことを防止することができる。 Encryption of user data in the encryption unit 510 is performed using key information. The key information used here is input to the information generating apparatus 100 as auxiliary data. Therefore, in the second embodiment, recording is performed with the key information embedded in the user data as an intentional error. Therefore, it is possible to prevent the data size from increasing in order to record the key information.
　一方、第２実施形態に係る情報再生装置２００は、ホログラフィックメモリ３００に記録されたユーザデータを読み出し、暗号化されたユーザデータ及び補助データである鍵情報を再生結果として出力する。 On the other hand, the information reproducing apparatus 200 according to the second embodiment reads the user data recorded in the holographic memory 300 and outputs the encrypted user data and key information which is auxiliary data as a reproduction result.
　暗号化されたユーザデータ及び補助データは、第３復号部５２０に入力される。第３復号部５２０は、補助データである鍵情報を用いて暗号化されたユーザデータを復号し、復号されたユーザデータを出力する。 The encrypted user data and auxiliary data are input to the third decryption unit 520. The third decryption unit 520 decrypts user data encrypted using the key information that is auxiliary data, and outputs the decrypted user data.
　以上説明したように、第２実施形態に係る情報生成装置及び情報再生装置によれば、ユーザデータに対するセキュリティが向上しているため、情報をより好適に記録及び再生することが可能である。また、上述した第１実施形態と同様に、データ量の増大を防止しつつ、補助データが確実に再生可能とされているため、実践上極めて有利である。 As described above, according to the information generating apparatus and the information reproducing apparatus according to the second embodiment, since the security for user data is improved, information can be recorded and reproduced more suitably. Further, as in the first embodiment described above, the auxiliary data can be reliably reproduced while preventing an increase in the amount of data, which is extremely advantageous in practice.
　＜第３実施形態＞
　次に、第３実施形態に係る情報生成装置及び情報再生装置について、図１１から図１４を参照して説明する。ここに図１１は、第３実施形態に係る情報生成装置及び情報再生装置の構成を示すブロック図であり、図１２から図１４は夫々、位置情報生成部の構成を示すブロック図である。尚、第３実施形態は、上述した第１実施形態と比べて、位置情報生成部の構成及び動作が異なり、他の構成や動作等は概ね同じである。よって、ここでは第１実施形態と異なる部分について詳細に説明し、他の重複する部分については適宜説明を省略する。また図１１では、上述した第１実施形態に係る情報生成装置及び情報再生装置の各構成要素と同様の構成要素に同一の参照符号を付している。 <Third Embodiment>
Next, an information generating apparatus and an information reproducing apparatus according to the third embodiment will be described with reference to FIGS. FIG. 11 is a block diagram showing the configuration of the information generating device and the information reproducing device according to the third embodiment, and FIGS. 12 to 14 are block diagrams showing the configuration of the position information generating unit. Note that the third embodiment differs from the first embodiment described above in the configuration and operation of the position information generation unit, and the other configurations and operations are generally the same. Therefore, a different part from 1st Embodiment is demonstrated in detail here, and description is abbreviate | omitted suitably about another overlapping part. In FIG. 11, the same reference numerals are assigned to the same constituent elements as those of the information generating apparatus and the information reproducing apparatus according to the first embodiment described above.
　図１１において、第３実施形態に係る情報生成装置１００には、ユーザデータ及び補助データに加えて、位置情報を暗号化するための鍵情報が入力される。鍵情報は、図に示すように、位置情報生成部１２０に入力される。 In FIG. 11, in addition to user data and auxiliary data, key information for encrypting position information is input to the information generating apparatus 100 according to the third embodiment. The key information is input to the position information generation unit 120 as shown in the figure.
　図１２において、位置情報生成部１２０は、例えば生成部１２１と、位置情報暗号化部１２２とを備えて構成される。生成部１２１は、入力されたユーザデータに基づいて位置情報を生成し、位置情報暗号化部１２２に出力する。位置情報暗号化部は、生成された位置情報を鍵情報を用いて暗号化し、暗号化された位置情報として出力する。 In FIG. 12, the position information generation unit 120 includes, for example, a generation unit 121 and a position information encryption unit 122. The generation unit 121 generates position information based on the input user data and outputs the position information to the position information encryption unit 122. The position information encryption unit encrypts the generated position information using the key information, and outputs the encrypted position information as encrypted position information.
　上述したように構成すれば、鍵情報がないと位置情報を生成することができないため、位置情報のセキュリティを向上させることができる。即ち、補助データが不正に再生されてしまうようなことを効果的に防止することが可能である。 If configured as described above, the location information cannot be generated without the key information, so that the security of the location information can be improved. That is, it is possible to effectively prevent the auxiliary data from being illegally reproduced.
　図１３において、位置情報生成部１２０は、ユーザデータ暗号化部１２３と、生成部１２１とを備えて構成されてもよい。この場合、先ずユーザデータ暗号化部１２３にユーザデータ及び鍵情報が入力され、ユーザデータが暗号化される。そして、生成部１２１は、暗号化されたユーザデータを用いて位置情報を生成する。ここでの構成は、上述した第２実施形態と比較的近いものとなる。 In FIG. 13, the position information generation unit 120 may include a user data encryption unit 123 and a generation unit 121. In this case, first, user data and key information are input to the user data encryption unit 123, and the user data is encrypted. Then, the generation unit 121 generates location information using the encrypted user data. The configuration here is relatively close to that of the second embodiment described above.
　上述した構成によれば、位置情報は直接暗号化されないが、元となるユーザデータが暗号化されている。このため、暗号化されていないユーザデータを用いて位置情報を生成する場合と比較すると、位置情報のセキュリティを向上させることが可能である。 According to the configuration described above, the location information is not directly encrypted, but the original user data is encrypted. For this reason, it is possible to improve the security of position information as compared with the case where position information is generated using unencrypted user data.
　図１４において、位置情報生成部１２０はＨＭＡＣ処理部１２４を備えて構成されてもよい。この場合、ユーザデータ及び鍵情報はＨＭＡＣ処理部１２４に入力され、ＨＭＡＣ処理部１２４から出力された位置情報（ハッシュ値）が出力される。 In FIG. 14, the position information generation unit 120 may be configured to include an HMAC processing unit 124. In this case, user data and key information are input to the HMAC processing unit 124, and position information (hash value) output from the HMAC processing unit 124 is output.
　上述した構成によれば、ＨＭＡＣを用いることで、図１２及び図１３で示したように、位置情報を生成する部位及びユーザデータ或いは位置情報を暗号化する部位を別々に設けなくとも済む。よって、比較的簡単な構成で、位置情報のセキュリティ向上を実現することが可能である。 According to the configuration described above, by using the HMAC, as shown in FIGS. 12 and 13, it is not necessary to separately provide a part for generating position information and a part for encrypting user data or position information. Therefore, it is possible to improve the security of position information with a relatively simple configuration.
　図１１に戻り、第３実施形態に係る情報再生装置２００には、データを再生する際に鍵情報が入力される。尚、鍵情報は、ホログラフィックメモリ３００に記録されていてもよいし、他の記録媒体に記録されていてもよい。 Returning to FIG. 11, the information reproducing apparatus 200 according to the third embodiment receives key information when reproducing data. The key information may be recorded in the holographic memory 300 or may be recorded on another recording medium.
　鍵情報は、第２位置情報生成部２４０に入力され、第２位置情報生成部２４０からは暗号化された位置情報が抽出部２５０に出力される。尚、第２位置情報生成部２４０は、図１２から図１３に示したような構成をとることができる。 The key information is input to the second position information generation unit 240, and the encrypted position information is output from the second position information generation unit 240 to the extraction unit 250. The second position information generation unit 240 can have a configuration as shown in FIGS.
　以上説明したように、第３実施形態に係る情報生成装置及び情報再生装置によれば、位置情報に対するセキュリティが向上させられているため、補助データを確実に保護しつつ記録及び再生を行うことができる。また、上述した第１実施形態と同様に、データ量の増大を防止しつつ、補助データが確実に再生可能とされているため、実践上極めて有利である。 As described above, according to the information generating apparatus and the information reproducing apparatus according to the third embodiment, since the security for the position information is improved, it is possible to perform recording and reproduction while reliably protecting the auxiliary data. it can. Further, as in the first embodiment described above, the auxiliary data can be reliably reproduced while preventing an increase in the amount of data, which is extremely advantageous in practice.
　＜第４実施形態＞
　次に、第４実施形態に係る情報生成装置及び情報再生装置について、図１５及び図１６を参照して説明する。ここに図１５は、第４実施形態に係る情報生成装置における、位置情報の生成及び補助データの置換方法を示す概念図であり、図１６は、第４実施形態に係る情報再生装置における、補助データの再生方法を示す概念図である。尚、第４実施形態は、上述した第１実施形態と比べて、補助データを変更させる点が異なり、その他の構成や動作等は概ね同じである。よって、ここでは第１実施形態と異なる部分について詳細に説明し、他の重複する部分については適宜説明を省略する。 <Fourth embodiment>
Next, an information generating apparatus and an information reproducing apparatus according to the fourth embodiment will be described with reference to FIGS. 15 and 16. FIG. 15 is a conceptual diagram showing a method for generating position information and replacing auxiliary data in the information generating apparatus according to the fourth embodiment, and FIG. 16 is an auxiliary diagram in the information reproducing apparatus according to the fourth embodiment. It is a conceptual diagram which shows the reproducing method of data. Note that the fourth embodiment differs from the first embodiment described above in that auxiliary data is changed, and other configurations and operations are generally the same. Therefore, a different part from 1st Embodiment is demonstrated in detail here, and description is abbreviate | omitted suitably about another overlapping part.
　図１５において、第４実施形態に係る情報生成装置１００では、補助データが置換部１４０においてユーザデータの一部と置換される前に、位置情報を用いて変更される。即ち、位置情報は、補助データを置換する位置を示すという役割に加えて、補助データの値を変更するという役割を持っている。 In FIG. 15, in the information generating apparatus 100 according to the fourth embodiment, the auxiliary data is changed using the position information before being replaced with part of the user data in the replacement unit 140. That is, the position information has a role of changing the value of the auxiliary data in addition to the role of indicating the position where the auxiliary data is replaced.
　例えば、誤り訂正符号が付加された補助データ（Ａ１、Ａ２及びＥ１）は、位置情報である７，２，５，６，８，・・・と共に演算処理が施されることにより、別の値へと変更される。尚、ここでの演算処理（即ち、図中で示す“＋”）は、ＸＯＲ演算であるとする。具体的には、補助データＡ１は、位置情報の先頭の値“７”とＸＯＲ演算されることでＡ１’とされる。補助データＡ２は、位置情報の２番目の値“２”とＸＯＲ演算されることでＡ２’とされる。補助データに付加された誤り訂正符号Ｅ１は、位置情報の３番目の値“５”とＸＯＲ演算されることでＥ１’とされる。 For example, auxiliary data (A1, A2, and E1) to which an error correction code is added is subjected to arithmetic processing together with positional information 7, 2, 5, 6, 8,. Is changed to It is assumed that the arithmetic processing here (that is, “+” shown in the figure) is an XOR operation. Specifically, the auxiliary data A1 is set to A1 ′ by performing an XOR operation with the leading value “7” of the position information. The auxiliary data A2 is set to A2 'by performing an XOR operation with the second value "2" of the position information. The error correction code E1 added to the auxiliary data is set to E1 ′ by performing an XOR operation with the third value “5” of the position information.
　位置情報によって変更された補助データ（Ａ１’，Ａ２’及びＥ１’）は、上述した各実施形態と同様に、置換部１４０によって、ユーザデータの一部と置換される。 The auxiliary data (A1 ′, A2 ′ and E1 ′) changed by the position information is replaced with a part of the user data by the replacement unit 140 as in the above-described embodiments.
　図１６において、第４実施形態に係る情報再生装置２００では、抽出された補助データ（Ｄ４，Ｄ６及びＤ１０）が位置情報に基づいて変更されたものとなる。よって、ここでは抽出された補助データが、位置情報に基づいて再変更される。例えば、上述したようにＸＯＲ演算処理によって補助データを変更した場合には、再び位置情報を用いてＸＯＲ演算処理を行うことによって、ＸＯＲ演算処理の効果が打ち消され、補助データは元の値（Ａ１，Ａ２及びＥ１）となる。尚、ＸＯＲ演算処理以外の演算処理であっても、位置情報を用いて可逆的に補助データを変更できるような演算処理であれば、利用することが可能である。 In FIG. 16, in the information reproducing apparatus 200 according to the fourth embodiment, the extracted auxiliary data (D4, D6 and D10) are changed based on the position information. Therefore, here, the extracted auxiliary data is re-changed based on the position information. For example, when the auxiliary data is changed by the XOR operation processing as described above, the XOR operation processing is performed again using the position information, thereby canceling the effect of the XOR operation processing, and the auxiliary data is restored to the original value (A1 , A2 and E1). It should be noted that arithmetic processing other than XOR arithmetic processing can be used as long as the arithmetic processing can reversibly change auxiliary data using position information.
　以上説明したように、第４実施形態に係る情報生成装置及び情報再生装置によれば、補助データが位置情報によって変更されることにより、補助データのセキュリティが向上させられているため、補助データを確実に保護しつつ記録及び再生を行うことができる。また、上述した第１実施形態と同様に、データ量の増大を防止しつつ、補助データが確実に再生可能とされているため、実践上極めて有利である。 As described above, according to the information generating apparatus and the information reproducing apparatus according to the fourth embodiment, the security of the auxiliary data is improved by changing the auxiliary data according to the position information. Recording and reproduction can be performed while ensuring protection. Further, as in the first embodiment described above, the auxiliary data can be reliably reproduced while preventing an increase in the amount of data, which is extremely advantageous in practice.
　＜第５実施形態＞
　次に、第５実施形態に係る情報生成装置及び情報再生装置について、図１７から図２４を参照して説明する。尚、第５実施形態は、上述した第１実施形態と比べて、位置情報に代えて変更情報を用いる点が異なり、その他の構成や動作等は概ね同じである。よって、ここでは第１実施形態と異なる部分について詳細に説明し、他の重複する部分については適宜説明を省略する。 <Fifth Embodiment>
Next, an information generating apparatus and an information reproducing apparatus according to the fifth embodiment will be described with reference to FIGS. The fifth embodiment is different from the first embodiment described above in that change information is used instead of position information, and other configurations and operations are substantially the same. Therefore, a different part from 1st Embodiment is demonstrated in detail here, and description is abbreviate | omitted suitably about another overlapping part.
　先ず、第５実施形態に係る情報生成装置の構成について、図１７及び図１８を参照して説明する。ここに図１７は、第５実施形態に係る情報生成装置及び情報再生装置の構成を示すブロック図であり、図１８は、第５実施形態に係る情報生成装置及び情報再生装置の変形例を示すブロック図である。 First, the configuration of the information generation apparatus according to the fifth embodiment will be described with reference to FIGS. 17 and 18. FIG. 17 is a block diagram showing the configuration of the information generating apparatus and the information reproducing apparatus according to the fifth embodiment, and FIG. 18 shows a modification of the information generating apparatus and the information reproducing apparatus according to the fifth embodiment. It is a block diagram.
　図１７において、第５実施形態に係る情報生成装置１００は、符号化部１１０と、第２符号化部１３０と、置換部１４０と、変調部１５０と、書き込み部１６０と、変更情報生成部１７０と、変更部１８０とを備えて構成されている。 In FIG. 17, the information generation apparatus 100 according to the fifth embodiment includes an encoding unit 110, a second encoding unit 130, a replacement unit 140, a modulation unit 150, a writing unit 160, and a change information generation unit 170. And a changing unit 180.
　符号化部１１０は、本発明の「符号化手段」の一例であり、入力されたユーザデータ（例えば、映像ファイルや音楽ファイル、文書ファイルなどの記録すべきデータ）に対して誤り訂正符号を付加する。 The encoding unit 110 is an example of the “encoding unit” of the present invention, and adds an error correction code to input user data (for example, data to be recorded such as a video file, a music file, a document file). To do.
　第２符号化部１３０は、本発明の「補助符号化手段」の一例であり、入力された補助データに対して誤り訂正符号を付加する。補助データは、ユーザデータに関連する補助的なデータであり、ユーザデータとは異なる用途で用いられる。補助データの例として、ユーザデータの属性、ファイル名前及び管理番号等を示すデータや、分割されたユーザデータの分割位置を示すデータ、ユーザデータが不正にコピーされたデータであるか否かを識別するためのデータ等が挙げられる。尚、符号化部１１０及び第２符号化部１３０を同一の演算回路等から構成するようにしてもよい。 The second encoding unit 130 is an example of the “auxiliary encoding unit” of the present invention, and adds an error correction code to the input auxiliary data. The auxiliary data is auxiliary data related to the user data, and is used for a purpose different from the user data. As an example of auxiliary data, data indicating user data attributes, file name, management number, etc., data indicating the division position of divided user data, and whether or not user data is illegally copied data Data and the like. Note that the encoding unit 110 and the second encoding unit 130 may be configured by the same arithmetic circuit or the like.
　変更情報生成部１７０は、本発明の「変更情報生成手段」の一例であり、入力されたユーザ情報に基づいて、補助データを変更するための変更情報を生成する。変更情報は、ユーザ情報から一意的に求められるような情報である。 The change information generation unit 170 is an example of the “change information generation unit” of the present invention, and generates change information for changing auxiliary data based on the input user information. The change information is information that is uniquely obtained from the user information.
　変更部１８０は、本発明の「補助データ変更手段」の一例であり、変更情報生成部１７０において生成された変更情報を用いて、符号化された補助データを変更する。補助データの変更は、例えば補助データ及び変更情報を用いた演算処理によって行われる。 The changing unit 180 is an example of the “auxiliary data changing unit” of the present invention, and changes the encoded auxiliary data using the change information generated by the change information generating unit 170. The change of the auxiliary data is performed, for example, by an arithmetic process using auxiliary data and change information.
　置換部１４０は、本発明の「置換手段」の一例であり、符号化部１１０において符号化されたユーザデータの一部を、変更部１８０において変更された補助データと置換する。 The replacement unit 140 is an example of the “replacement unit” in the present invention, and replaces part of the user data encoded by the encoding unit 110 with auxiliary data changed by the changing unit 180.
　変調部１５０は、置換部１４０において置換されたユーザデータを記録するのに適切な方式のデータへと変調する。本実施形態のようにホログラフィックメモリ３００に対して情報を記録する場合には、例えば２ビットのデータを４つの画素で示す（２，４）変調や、６ビットのデータを９つの画素で示す（６，９）変調等が用いられる。 The modulation unit 150 modulates the user data replaced by the replacement unit 140 into data of an appropriate system for recording. When information is recorded in the holographic memory 300 as in the present embodiment, for example, (2, 4) modulation in which 2 bits of data are indicated by 4 pixels and 6 bits of data are indicated by 9 pixels. (6, 9) modulation or the like is used.
　書き込み部１６０は、例えば光源やレンズ等を含んで構成されており、光源から出射されたレーザ光をレンズで集光してホログラフィックメモリ３００に照射し、干渉縞としてユーザデータを記憶する。 The writing unit 160 includes, for example, a light source, a lens, and the like, condenses the laser light emitted from the light source with the lens, irradiates the holographic memory 300, and stores user data as interference fringes.
　図１８において、第５実施形態に係る情報生成装置及び情報再生装置は、上述した情報の記録以外に、例えば通信によって情報をやり取りする場合にも利用することが可能である。このような場合は、変調部１５０において通信用に変調されたユーザデータが、例えば図に示すような通信ケーブル４００を介して電気信号として伝送される。情報生成装置及び情報再生装置は、電気信号の変調や復調に加えて、同期信号を用いた情報位置の特定や管理情報の処理等を行う。 In FIG. 18, the information generating apparatus and the information reproducing apparatus according to the fifth embodiment can be used not only for recording the information described above but also for exchanging information by communication, for example. In such a case, user data modulated for communication in the modulation unit 150 is transmitted as an electrical signal via a communication cable 400 as shown in the figure, for example. In addition to modulation and demodulation of electrical signals, the information generation device and the information reproduction device perform information position specification, management information processing, and the like using a synchronization signal.
　続いて、第５実施形態に係る情報生成装置の動作について、図１７に加えて、図１９から図２１を参照して説明する。ここに図１９は、第５実施形態に係る情報生成装置の動作の流れを示すフローチャートである。また図２０は、変更情報の生成方法について示す概念図であり、図２１は、変更情報を用いた補助データの変更方法について示す概念図である。 Subsequently, the operation of the information generating apparatus according to the fifth embodiment will be described with reference to FIGS. 19 to 21 in addition to FIG. FIG. 19 is a flowchart showing an operation flow of the information generating apparatus according to the fifth embodiment. FIG. 20 is a conceptual diagram illustrating a method for generating change information, and FIG. 21 is a conceptual diagram illustrating a method for changing auxiliary data using the change information.
　図１７及び図１９において、第５実施形態に係る情報生成装置１００の動作時には、先ず符号化部１１０にユーザデータが入力される。符号化部１１０は、入力されたユーザデータに対して誤り訂正符号を付加する（ステップＳ３１）。これにより、ユーザデータの一部に誤りが生じた場合であっても、誤り訂正符号を用いて正しいデータを修復することが可能となる。図２０に示すように、ユーザデータに対する誤り訂正符号（Ｃ１～Ｃ４）は、典型的には、ユーザデータ（Ｕ１～Ｕ８）の最後の部分に付加される。但し、インターリーブ等によって、各データの配置が並び替えられてもよい。 17 and 19, user data is first input to the encoding unit 110 when the information generating apparatus 100 according to the fifth embodiment operates. The encoding unit 110 adds an error correction code to the input user data (step S31). As a result, even if an error occurs in a part of user data, correct data can be restored using the error correction code. As shown in FIG. 20, error correction codes (C1 to C4) for user data are typically added to the last part of user data (U1 to U8). However, the arrangement of each data may be rearranged by interleaving or the like.
　他方で、第２符号化部１３０には補助データが入力される。第２符号化部１３０は、補助データに対し誤り訂正符号を付加する（ステップＳ３２）。これにより、補助データも、ユーザデータと同様に誤り訂正能力を有することになる。図２１に示すように、補助データに対する誤り訂正符号（Ｅ１）は、典型的には、補助データ（Ａ１及びＡ２）の最後の部分に付加される。但し、上述したユーザデータと同様に、インターリーブ等によって、各データの配置が並び替えられてもよい。 On the other hand, auxiliary data is input to the second encoding unit 130. The second encoding unit 130 adds an error correction code to the auxiliary data (step S32). As a result, the auxiliary data also has an error correction capability like the user data. As shown in FIG. 21, the error correction code (E1) for the auxiliary data is typically added to the last part of the auxiliary data (A1 and A2). However, similarly to the user data described above, the arrangement of each data may be rearranged by interleaving or the like.
　ユーザデータは、上述した符号化部１１０に加えて、変更情報生成部１７０にも入力されている。変更情報生成部１７０は、入力されたユーザデータに基づいて、補助データを変更するための変更情報を生成する（ステップＳ３３）。変更情報は、例えばハッシュ関数により生成されるハッシュ値を用いることができ、ハッシュ関数にＳＨＡ－１（Secure Hash Algorithm 1）を用いる場合には、任意長の入力値（即ち、ユーザデータ）に対して、１６０ビットの出力値（即ち、変更情報）が得られる。尚、変更情報は、ハッシュ値のように、ユーザデータから一意的に求められる情報である。 User data is input to the change information generation unit 170 in addition to the encoding unit 110 described above. The change information generation unit 170 generates change information for changing the auxiliary data based on the input user data (step S33). As the change information, for example, a hash value generated by a hash function can be used. When SHA-1 (Secure Hash Algorithm 1) is used for the hash function, an input value of an arbitrary length (that is, user data) Thus, a 160-bit output value (that is, change information) is obtained. The change information is information uniquely obtained from user data, such as a hash value.
　変更情報生成部１７０において生成された変更情報は、変更部１８０に入力される。また、変更部１８０には、第２符号化部１３０において符号化された補助データも入力される。変更部１８０は、変更情報に基づいて補助データを変更する（ステップＳ３４）。 The change information generated in the change information generation unit 170 is input to the change unit 180. In addition, auxiliary data encoded by the second encoding unit 130 is also input to the changing unit 180. The changing unit 180 changes the auxiliary data based on the change information (step S34).
　図２０に示すように、変更情報生成部１７０によって、ユーザデータ（Ｕ１～Ｕ８）から、７，２，５，６，８，・・・といった変更情報が生成されているとする。この場合、変更部１８０は、変更情報の各値と補助データとで演算処理を行うことで、補助データを変更する。尚、ここでの演算処理（即ち、図中で示す“＋”）は、ＸＯＲ演算であるとする。具体的には、補助データＡ１は、変更情報の先頭の値“７”とＸＯＲ演算されることでＡ１’とされる。補助データＡ２は、変更情報の２番目の値“２”とＸＯＲ演算されることでＡ２’とされる。補助データに付加された誤り訂正符号Ｅ１は、変更情報の３番目の値“５”とＸＯＲ演算されることでＥ１’とされる。 20, it is assumed that change information such as 7, 2, 5, 6, 8,... Is generated from the user data (U1 to U8) by the change information generation unit 170. In this case, the changing unit 180 changes the auxiliary data by performing arithmetic processing using each value of the change information and the auxiliary data. It is assumed that the arithmetic processing here (that is, “+” shown in the figure) is an XOR operation. Specifically, the auxiliary data A1 is set to A1 ′ by performing an XOR operation with the leading value “7” of the change information. The auxiliary data A2 is set to A2 'by performing an XOR operation with the second value "2" of the change information. The error correction code E1 added to the auxiliary data is set to E1 ′ by performing an XOR operation with the third value “5” of the change information.
　上述したように、ここでは１つの補助データに対して１つの変更情報を用いて変更するため、変更情報の値の数は、置換する補助データの数（即ち、ここではＡ１、Ａ２及びＥ１の３つ）と同じ、或いはそれ以上であることが望ましい。但し、例えば変更情報としてハッシュ関数を用いており、補助データの値の数の方がハッシュ値より多く、変更情報の値が不足してしまう場合には、ハッシュ関数の出力を更にハッシュ関数に入力した値（即ち、ハッシュ値のハッシュ値）を生成することで対応することが可能である。 As described above, here, since one piece of auxiliary data is changed using one piece of change information, the number of values of change information is the number of pieces of auxiliary data to be replaced (that is, A1, A2, and E1 here). It is desirable to be equal to or more than (3). However, if, for example, a hash function is used as change information, the number of auxiliary data values is greater than the hash value, and if the change information value is insufficient, the output of the hash function is further input to the hash function. It is possible to cope with this by generating the obtained value (that is, the hash value of the hash value).
　位置情報によって変更された補助データ（Ａ１’，Ａ２’及びＥ１’）は夫々、置換部１４０に出力される。置換部は、変更された補助データの各々を、ユーザデータの各ブロックにおけるポジション３の位置にあるユーザデータと置換する（ステップＳ３５）。具体的には、図２１に示すように、補助データの先頭の値Ａ１’は、ユーザデータの第１ブロックにおけるポジション３に位置するＵ４と置換される。補助データの２つ目の値Ａ２’は、ユーザデータの第２ブロックにおけるポジション３に位置するＵ８と置換される。補助データの誤り訂正符号の値Ｅ１’は、ユーザデータの第３ブロックにおけるポジション３に位置するＣ４と置換される。以上のように置換すれば、比較的容易に、且つユーザデータに対して、均等に補助データを埋め込むことができる。ユーザデータは、誤り訂正符号を付加された後に補助データと置換されることとなるため、置換された補助データは意図的な誤りとして扱われる。 The auxiliary data (A1 ′, A2 ′, and E1 ′) changed by the position information is output to the replacement unit 140, respectively. The replacement unit replaces each changed auxiliary data with the user data at position 3 in each block of user data (step S35). Specifically, as shown in FIG. 21, the leading value A1 'of the auxiliary data is replaced with U4 located at position 3 in the first block of user data. The second value A2 'of the auxiliary data is replaced with U8 located at position 3 in the second block of user data. The error correction code value E1 'of the auxiliary data is replaced with C4 located at position 3 in the third block of user data. By replacing as described above, auxiliary data can be embedded relatively easily and evenly in user data. Since the user data is replaced with auxiliary data after an error correction code is added, the replaced auxiliary data is treated as an intentional error.
　尚、ここでは補助データとユーザデータにおけるポジション３に位置するデータとを置換するものとしたが、このような置換法則は設計事項であり、適宜変更することが可能である。即ち、後述する情報再生装置において、補助データがどの位置のユーザデータと置換されたかが分かるようにすればよく、置換に用いる法則は特に限定されない。 Here, the auxiliary data and the data located at position 3 in the user data are replaced, but such a replacement rule is a design matter and can be changed as appropriate. In other words, in the information reproducing apparatus to be described later, it is only necessary to know where the auxiliary data is replaced with the user data, and the law used for the replacement is not particularly limited.
　図１７及び図１９に戻り、ユーザデータの一部が補助データに置換されると、変調部１５０は、ユーザデータを記録に適した方式に変調する（ステップＳ３６）。書き込み部１６０は、変調したユーザデータをホログラフィックメモリ３００に記録する（ステップＳ３７）。尚、本実施形態に係る情報生成装置では、補助データを変更するために用いた変更情報はホログラフィックメモリ３００には記録されない。また他の記録媒体にも記録する必要はない。よって、ここで記録されるデータの大きさは、記録すべきユーザデータの大きさと同じで済む。 17 and 19, when a part of the user data is replaced with the auxiliary data, the modulation unit 150 modulates the user data into a method suitable for recording (step S36). The writing unit 160 records the modulated user data in the holographic memory 300 (step S37). In the information generating apparatus according to this embodiment, the change information used for changing the auxiliary data is not recorded in the holographic memory 300. Moreover, it is not necessary to record on another recording medium. Therefore, the size of the data recorded here is the same as the size of the user data to be recorded.
　次に、第５実施形態に係る情報再生装置の構成について、再び図１７及び図１９を参照して説明する。 Next, the configuration of the information reproducing apparatus according to the fifth embodiment will be described with reference to FIGS. 17 and 19 again.
　図１７において、第１実施形態に係る情報再生装置２００は、読み出し部２１０と、復調部２２０と、復号部２３０と、抽出部２５０と、第２復号部２６０と、第２変更情報生成部２７０と、再変更部２８０とを備えて構成されている。 In FIG. 17, the information reproducing apparatus 200 according to the first embodiment includes a reading unit 210, a demodulating unit 220, a decoding unit 230, an extracting unit 250, a second decoding unit 260, and a second change information generating unit 270. And a re-changing unit 280.
　読み出し部２１０は、例えば発光部、レンズ及び受光素子を備えて構成されており、ホログラフィックメモリ３００にレーザ光を照射して得られる像を、受光素子によって検出し、検出された像からユーザデータを再生する。 The reading unit 210 includes, for example, a light emitting unit, a lens, and a light receiving element. The reading unit 210 detects an image obtained by irradiating the holographic memory 300 with laser light by the light receiving element, and user data is detected from the detected image. Play.
　復調部２２０は、情報生成装置１００における変調部１５０によって変調したユーザデータを元の状態へと復調する。即ち、変調部１５０とは逆の処理を行う。 The demodulator 220 demodulates the user data modulated by the modulator 150 in the information generation apparatus 100 to the original state. That is, the reverse process of the modulation unit 150 is performed.
　復号部２３０は、本発明の「復号手段」の一例であり、ユーザデータに付加された誤り訂正符号を用いて、ユーザデータに含まれる誤りを訂正する。 The decoding unit 230 is an example of the “decoding unit” of the present invention, and corrects an error included in user data using an error correction code added to the user data.
　抽出部２５０は、本発明の「抽出手段」の一例であり、復号前のユーザデータ（即ち、補助データが意図的な誤りとして含まれているユーザデータ）から、情報を生成した際の置換法則を用いて補助データを抽出する。 The extraction unit 250 is an example of the “extraction unit” of the present invention, and a replacement rule when information is generated from user data before decoding (that is, user data in which auxiliary data is included as an intentional error). To extract auxiliary data.
　第２復号部２６０は、抽出された補助データに付加されている誤り訂正符号を用いて、補助データに含まれる誤りを訂正する。 The second decoding unit 260 corrects an error included in the auxiliary data by using an error correction code added to the extracted auxiliary data.
　第２変更情報生成部２７０は、本発明の「第２変更情報生成手段」の一例であり、復号部２３０において復号されたユーザデータ（即ち、誤りが訂正されたユーザデータ）から、情報生成装置１００における変更情報生成部１７０と同様に変更情報を生成する。尚、変更情報生成部１７０を第２変更情報生成部２７０として用いることもできる。 The second change information generation unit 270 is an example of the “second change information generation unit” of the present invention, and the information generation device uses the user data decoded by the decoding unit 230 (that is, user data whose error is corrected). The change information is generated in the same manner as the change information generation unit 170 in 100. Note that the change information generation unit 170 can also be used as the second change information generation unit 270.
　再変更部２８０は、本発明の「再変更手段」の一例であり、第２変更情報生成部２７０によって生成された変更情報に基づいて、変更部１８０によって変更された状態の補助データに各種演算処理を施すことにより、変更前の補助データへと再変更する。 The re-change unit 280 is an example of the “re-change unit” of the present invention. Based on the change information generated by the second change information generation unit 270, the re-change unit 280 performs various operations on the auxiliary data changed by the change unit 180. By performing the processing, it is re-changed to the auxiliary data before the change.
　尚、本実施形態に係る情報再生装置を、図１８に示すような通信に用いる場合には、通信ケーブル４００を介して伝送されたデータが、復調部２２０に入力される。 Note that when the information reproducing apparatus according to the present embodiment is used for communication as shown in FIG. 18, data transmitted via the communication cable 400 is input to the demodulator 220.
　続いて、第５実施形態に係る情報再生装置の動作について、図１７に加えて、図２２から図２４を参照して説明する。ここに図２２は、第５実施形態に係る情報再生装置の動作の流れを示すフローチャートである。また図２３は、ユーザデータの復号及び変更情報の生成方法を示す概念図であり、図２４は、補助データの抽出及び再変更、並びに復号方法を示す概念図である。 Subsequently, the operation of the information reproducing apparatus according to the fifth embodiment will be described with reference to FIGS. 22 to 24 in addition to FIG. FIG. 22 is a flowchart showing an operation flow of the information reproducing apparatus according to the fifth embodiment. FIG. 23 is a conceptual diagram illustrating a method for generating user data decoding and change information, and FIG. 24 is a conceptual diagram illustrating auxiliary data extraction and re-change and a decoding method.
　図１７及び図２２において、本実施形態に係る情報再生装置２００の動作時には、先ず読み出し部２１０が、ホログラフィックメモリ３００に記録されたユーザデータを読み出す（ステップＳ４１）。続いて、復調部２２０が、読み出されたユーザデータを変調前の状態に復調する（ステップＳ４２）。 17 and 22, when the information reproducing apparatus 200 according to the present embodiment operates, the reading unit 210 first reads user data recorded in the holographic memory 300 (step S41). Subsequently, the demodulator 220 demodulates the read user data to a state before modulation (step S42).
　ユーザデータが復調されると、復号部２３０は、ユーザデータに付加されている誤り訂正符号を用いて、ユーザデータに含まれる誤りを訂正する（ステップＳ４３）。この際、情報生成装置１００における置換部１４０によってユーザデータの一部と置換された補助データは、誤りとして訂正される。即ち、補助データは置換前のユーザデータとされる。復号されたユーザデータは、再生結果として外部に出力されると共に、第２変更情報生成部２７０に対しても出力される。第２変更情報生成部２７０は、復号されたユーザデータを用いて変更情報を生成する（ステップＳ４４）。 When the user data is demodulated, the decoding unit 230 corrects the error included in the user data using the error correction code added to the user data (step S43). At this time, the auxiliary data replaced with part of the user data by the replacement unit 140 in the information generating apparatus 100 is corrected as an error. That is, the auxiliary data is user data before replacement. The decrypted user data is output to the outside as a reproduction result and also output to the second change information generation unit 270. The second change information generation unit 270 generates change information using the decrypted user data (step S44).
　図２３において、読み出し部２１０によって読み出された際のユーザデータ（Ｄ１～Ｄ１２）には、意図的な誤りである補助データに加えて、ホログラフィックメモリ３００における傷や、記録及び再生時のノイズ等によって、いくつかの誤りが含まれている。復号部２３０は、このような誤りを含んだユーザデータを復号し、置換前のユーザデータ（Ｕ１～Ｕ８）とする。ユーザデータは、情報生成装置１００における変更情報生成部１７０が用いたユーザデータと同一のデータであるので、第２変更情報生成部２７０において生成される変更情報は、変更情報生成部１７０において生成された変更情報と同一のものとなる。このように、ユーザデータが復号できるのであれば、第２変更情報生成部２７０において再び同一の変更情報を生成することができる。よって、変更情報生成部１２０において生成した変更情報を、ホログラフィックメモリ３００や別の記録媒体等に記録しておく必要がない。 In FIG. 23, user data (D1 to D12) read by the reading unit 210 includes scratches in the holographic memory 300, noise during recording and reproduction, in addition to auxiliary data that is an intentional error. Etc., some errors are included. The decoding unit 230 decodes the user data including such an error and uses it as user data (U1 to U8) before replacement. Since the user data is the same data as the user data used by the change information generation unit 170 in the information generation apparatus 100, the change information generated in the second change information generation unit 270 is generated in the change information generation unit 170. It becomes the same as the changed information. As described above, if the user data can be decoded, the second change information generation unit 270 can generate the same change information again. Therefore, it is not necessary to record the change information generated in the change information generation unit 120 in the holographic memory 300 or another recording medium.
　図１７及び図２２に戻り、抽出部２５０には、復号部２３０において復号される前のユーザデータも出力されている。抽出部２５０は、復号前のユーザデータから補助データを抽出する（ステップＳ４５）。抽出された補助データは、再変更部２８０に出力される。また再変更部２８０には、第２変更情報生成部２７０において生成された変更情報も出力されている。再変更部２８０は、変更情報に基づいて、抽出された補助データを再変更する（ステップＳ４６）。 17 and FIG. 22, user data before being decoded by the decoding unit 230 is also output to the extraction unit 250. The extraction unit 250 extracts auxiliary data from user data before decoding (step S45). The extracted auxiliary data is output to the re-changing unit 280. In addition, the change information generated in the second change information generation unit 270 is also output to the re-change unit 280. The re-change unit 280 re-changes the extracted auxiliary data based on the change information (step S46).
　図２４において、抽出部２５０は、復号前のユーザデータ（Ｄ１～Ｄ１２）における各ブロックのポジション３の位置から夫々データを抽出する。これにより、置換されていた補助データが抽出される。ここで抽出された補助データ（Ｄ４，Ｄ８及びＤ１２）は、変更部１８０によって変更された状態であるので、再変更部２８０は、変更情報に基づいて抽出された補助データを再変更する。例えば、上述したようにＸＯＲ演算処理によって補助データを変更した場合には、再び位置情報を用いてＸＯＲ演算処理を行うことによって、ＸＯＲ演算処理の効果が打ち消され、補助データは元の値（Ａ１，Ａ２及びＥ１）となる。尚、ＸＯＲ演算処理以外の演算処理であっても、位置情報を用いて可逆的に補助データを変更できるような演算処理であれば、利用することが可能である。 24, the extraction unit 250 extracts data from the position of the position 3 of each block in the user data (D1 to D12) before decoding. As a result, the auxiliary data that has been replaced is extracted. Since the auxiliary data (D4, D8, and D12) extracted here is changed by the changing unit 180, the re-changing unit 280 re-changes the auxiliary data extracted based on the change information. For example, when the auxiliary data is changed by the XOR operation processing as described above, the XOR operation processing is performed again using the position information, thereby canceling the effect of the XOR operation processing, and the auxiliary data is restored to the original value (A1 , A2 and E1). It should be noted that arithmetic processing other than XOR arithmetic processing can be used as long as the arithmetic processing can reversibly change auxiliary data using position information.
　上述したように、補助データが変更されていることにより、仮に補助データのみが不正に抽出された場合であっても、抽出された補助データは変更された状態にあるため、単独では再生することができない。よって、補助データに対するセキュリティを向上させることが可能である。尚、上述した第２及び第３実施形態に示したように、他の鍵情報を用いた暗号化と組み合わせれば、より高いセキュリティを実現することが可能である。 As described above, even if only the auxiliary data is illegally extracted because the auxiliary data has been changed, the extracted auxiliary data is in a changed state, so that it is reproduced alone. I can't. Therefore, it is possible to improve security for auxiliary data. As shown in the second and third embodiments, higher security can be realized by combining with encryption using other key information.
　再変更後の補助データは、第２復号部において誤りが訂正され、符号化前の補助データ（Ａ１及びＡ２）に復号される（ステップＳ４７）。復号された補助データは、再生結果として外部に出力される。 The error is corrected in the auxiliary data after re-change in the second decoding unit and decoded into auxiliary data (A1 and A2) before encoding (step S47). The decoded auxiliary data is output to the outside as a reproduction result.
　以上説明したように、第５実施形態に係る情報生成装置及び情報再生装置によれば、補助データのセキュリティを向上させることができる。また、補助データの変更に用いる変更情報をユーザデータの一部と置換して記録するため、記録すべき情報が増大してしまうことを防止することが可能である。 As described above, according to the information generating device and the information reproducing device according to the fifth embodiment, the security of auxiliary data can be improved. Further, since the change information used for changing the auxiliary data is replaced with a part of the user data and recorded, it is possible to prevent the information to be recorded from increasing.
　＜誤り訂正符号決定方法＞
　最後に、上述した第１から第５実施形態に係る情報生成装置及び情報再生装置において用いられる誤り訂正符号のパラメータ決定方法について、図２５から図２９を参照して詳細に説明する。ここに図２５及び図２９は夫々、符号化部から出力されるデータを示す概念図であり、図２６は、第２符号化部から出力されるデータを示す概念図である。また図２７及び図２８は夫々、補助データの分割について示す概念図である。 <Error correction code determination method>
Finally, the parameter determination method of the error correction code used in the information generating apparatus and information reproducing apparatus according to the first to fifth embodiments described above will be described in detail with reference to FIGS. 25 and 29 are conceptual diagrams showing data output from the encoding unit, and FIG. 26 is a conceptual diagram showing data output from the second encoding unit. 27 and 28 are conceptual diagrams showing the division of auxiliary data, respectively.
　上述した実施形態に係る情報生成装置及び情報再生装置では、補助データを意図的な誤りとして埋め込む分、想定している誤りに対して更に誤りを生じさせることになる。よって、誤り訂正が不可能になることを防止するため、十分な誤り訂正ができるよう、誤り訂正符号のパラメータを慎重に決定することが望ましい。 In the information generating apparatus and the information reproducing apparatus according to the above-described embodiment, the auxiliary data is embedded as an intentional error, and an error is further generated with respect to the assumed error. Therefore, in order to prevent error correction from being impossible, it is desirable to carefully determine the parameters of the error correction code so that sufficient error correction can be performed.
　図２５において、符号化部１１０（図１参照）が処理単位とするユーザデータの大きさをｋシンボル、出力の大きさをｎシンボルとする。即ち、ｎ－ｋシンボルの誤り訂正符号がユーザデータに付加されるものとする。この際、ｎシンボルのうち最大ｅシンボルが誤るものである、即ち符号化部１１０における誤り訂正能力がｅシンボルであるものとすると、下記の式（１）、
　　ｅ＜（ｎ－ｋ）／２　・・・（１）
を満たすようｎ及びｋを選べばよい。 In FIG. 25, it is assumed that the size of user data, which is the processing unit of the encoding unit 110 (see FIG. 1), is k symbols, and the output size is n symbols. That is, an error correction code of nk symbols is added to user data. At this time, if the maximum e symbols out of n symbols are erroneous, that is, the error correction capability in the encoding unit 110 is e symbols, the following equation (1),
e <(n−k) / 2 (1)
N and k may be selected to satisfy the above.
　ここでｅについて、記録再生時の雑音など装置に起因するもの及び傷など記録媒体に起因するものの両者に起因する成分（即ち、図中の“傷誤”）をｅ１、ユーザデータの一部を補助データで置き換えることに起因する成分（即ち、図中の“意誤”）をｅ２とおく（即ち、ｅ＝ｅ１＋ｅ２）。すると、ユーザデータを構成する各ブロックのブロック長Ｂについては、装置や記録媒体に起因する誤りが均一に分布しているという条件下では、Ｂ＝ｎ／ｅ２となる。但し、値が割り切れない場合は切り捨てるものとする。ブロック長Ｂについては、剰余演算を簡単に行うことができるようにするため、２の指数乗にすることが望ましい。これは２の指数乗の剰余演算が単なる下位ビットの抽出になるためである。 Here, for e, a component (namely, “scratch error” in the figure) due to both the noise caused by the apparatus such as noise at the time of recording / playback and the scratch caused by the recording medium (namely, “scratch error” in the figure), e1 A component resulting from the replacement with auxiliary data (that is, “incorrect” in the figure) is set to e2 (that is, e = e1 + e2). Then, the block length B of each block constituting the user data is B = n / e2 under the condition that errors due to the apparatus and the recording medium are uniformly distributed. However, if the value is not divisible, it will be rounded down. As for the block length B, it is desirable to make it an exponential power of 2 so that the remainder calculation can be easily performed. This is because the exponentiation of exponentiation of 2 simply extracts the lower bits.
　図２６において、第２符号化部１３０（図１参照）が処理単位とする補助データの大きさをｋ’シンボル、出力の大きさをｎ’シンボルとする。ｎ’シンボルのうち最大ｅ’シンボルが誤るものである、即ち、第２符号化部１３０における誤り訂正能力がｅ’シンボルであるものとすると、下記の式（２）、
　　ｅ’＜（ｎ’－ｋ’）／２　・・・（２）
を満たすようｎ’及びｋ’を選べばよい。 In FIG. 26, it is assumed that the size of the auxiliary data that is processed by the second encoding unit 130 (see FIG. 1) is k ′ symbol and the output size is n ′ symbol. Assuming that the maximum e ′ symbol among n ′ symbols is erroneous, that is, the error correction capability in the second encoding unit 130 is the e ′ symbol, the following equation (2),
e ′ <(n′−k ′) / 2 (2)
N ′ and k ′ may be selected so as to satisfy the above.
　図２７において、第２符号化部１３０では、例えば入力された補助データをｋ’シンボルずつに分割して誤り訂正符号を付加する。ここで、補助データ全体の大きさをＡシンボルとすると、誤り訂正符号生成及び付加処理の回数であるαは、下記の式（３）、
　　Ａ≦αｋ’　・・・（３）
を満たせばよい。尚、必ずしもＡがｋ’の倍数になるとは限らないので、このような場合には、図に示すように補助データにダミーデータを付加する、或いはゼロパディングを行うようにすればよい。 In FIG. 27, the second encoding unit 130 divides the input auxiliary data into k ′ symbols, for example, and adds an error correction code. Here, when the size of the auxiliary data as a whole is A symbol, α which is the number of error correction code generation and addition processing is expressed by the following equation (3),
A ≦ αk ′ (3)
Should be satisfied. Since A is not always a multiple of k ′, in such a case, dummy data may be added to the auxiliary data or zero padding may be performed as shown in the figure.
　図２８において、上述したαのうち最小となる値をα'とすると、第２符号化部１３０の基本処理単位はｎ’シンボルなので、ｋ’シンボルに分割された補助データでユーザデータを置換するためには、付加される誤り訂正符号を含めてｎ’シンボルのユーザデータを置換すればよい。よって、ユーザデータをＡシンボル分の補助データで置換するためには、α’ｎ’シンボルのユーザデータを置換すればよい。ｅ２シンボルを置換したい場合、対応するｋシンボル分のユーザデータがあればよいので、上述したα’ｎ’シンボルを置換するためのユーザデータをｘシンボルとすると、下記の式（４）
　　ｅ２：ｋ＝α’ｎ’：ｘ　・・・（４）
という比例関係が成立する。よって、上述した式（４）をｘについて解けば、下記の式（５）、
　　ｘ＝ｋα’ｎ’／ｅ２　・・・（５）
という結果が得られる。 In FIG. 28, if α ′ is the minimum value of α described above, the basic processing unit of the second encoding unit 130 is n ′ symbols, so user data is replaced with auxiliary data divided into k ′ symbols. For this purpose, the user data of n ′ symbols including the error correction code to be added may be replaced. Therefore, in order to replace user data with auxiliary data for A symbols, the user data for α′n ′ symbols may be replaced. When it is desired to replace the e2 symbol, it suffices if there is corresponding user data for k symbols. If the user data for replacing the α′n ′ symbol is x symbols, the following equation (4)
e2: k = α'n ': x (4)
The proportional relationship is established. Therefore, if the above equation (4) is solved for x, the following equation (5),
x = kα'n '/ e2 (5)
The result is obtained.
　図２９において、ｅ２シンボルを置換したい場合、符号化部１１０の出力がｎシンボルとなるため、上述したα’ｎ’シンボルを置換するために必要な符号化データをｙシンボルとすると、下記の式（６）
　　ｅ２：ｎ＝α’ｎ’：ｙ　・・・（６）
という比例関係が成立する。よって、上述した式（６）をｙについて解けば、下記の式（７）、
　　ｙ＝ｎα’ｎ’／ｅ２　・・・（７）
という結果が得られる。 In FIG. 29, when the e2 symbol is to be replaced, since the output of the encoding unit 110 is n symbols, if the encoded data necessary for replacing the above α′n ′ symbol is the y symbol, (6)
e2: n = α′n ′: y (6)
The proportional relationship is established. Therefore, if the above equation (6) is solved for y, the following equation (7),
y = nα'n '/ e2 (7)
The result is obtained.
　以上の結果から、これらの条件を満たすようユーザデータや補助データの大きさ、誤り訂正符号のシンボル数やブロック長を設定することで、上述した本実施形態に係る情報生成装置及び情報再生装置における効果を確実に得ることが可能となる。 From the above results, by setting the size of user data and auxiliary data, the number of symbols of the error correction code, and the block length so as to satisfy these conditions, the information generating apparatus and information reproducing apparatus according to the present embodiment described above An effect can be obtained with certainty.
　本発明は、上述した実施形態に限られるものではなく、請求の範囲及び明細書全体から読み取ることができる発明の要旨或いは思想に反しない範囲で適宜変更可能であり、そのような変更を伴う情報生成装置及び方法、情報再生装置及び方法、並びに記録媒体もまた本発明の技術的範囲に含まれるものである。 The present invention is not limited to the above-described embodiments, and can be appropriately changed without departing from the spirit or idea of the invention that can be read from the claims and the entire specification, and information accompanying such changes. The generating device and method, the information reproducing device and method, and the recording medium are also included in the technical scope of the present invention.
　本発明の情報生成装置及び方法、情報再生装置及び方法、並びに記録媒体は、例えばホログラフィックメモリ等の記録媒体に情報を記録する記録装置又は記憶された情報を再生する再生装置に利用可能である。また、情報をインターネット等によってやり取りする通信装置等においても利用可能である。 The information generating apparatus and method, the information reproducing apparatus and method, and the recording medium of the present invention can be used for a recording apparatus that records information on a recording medium such as a holographic memory or a reproducing apparatus that reproduces stored information. . It can also be used in communication devices that exchange information via the Internet or the like.

Claims (15)

  1. 　ユーザデータの一部を、前記ユーザデータに関連するデータであって、前記ユーザデータとは異なる用途で用いられる補助データに置換して、置換ユーザデータを生成する情報生成装置であって、
    　前記ユーザデータに対して誤り訂正符号を付加して、符号化データを生成する符号化手段と、
    　前記符号化データにおける前記補助データに置換されるデータの位置を示す位置情報を、前記ユーザデータに基づいて生成する位置情報生成手段と、
    　前記符号化データの一部を、前記位置情報に基づいて前記補助データに置換して、前記置換ユーザデータを生成する置換手段と
    　を備えることを特徴とする情報生成装置。     An information generation device that generates replacement user data by replacing a part of user data with auxiliary data that is related to the user data and is used for a different purpose from the user data,
    Encoding means for generating encoded data by adding an error correction code to the user data;
    Position information generating means for generating position information indicating the position of data to be replaced with the auxiliary data in the encoded data based on the user data;
    An information generation apparatus comprising: replacement means for replacing a part of the encoded data with the auxiliary data based on the position information to generate the replacement user data.
  2. 　前記符号化データは、所定数の連続するデータ毎にブロックとして分割されており、
    　前記置換手段は、前記ブロック毎に、前記符号化データを１つの補助データと置換する
    　ことを特徴とする請求の範囲第１項に記載の情報生成装置。     The encoded data is divided into blocks for each predetermined number of continuous data,
    The information generation apparatus according to claim 1, wherein the replacement unit replaces the encoded data with one auxiliary data for each block.
  3. 　前記補助データに対して誤り訂正符号を付加する補助符号化手段を更に備え、
    　前記置換手段は、前記符号化データの一部を前記誤り訂正符号が付加された補助データに置換して、置換ユーザデータを生成する
    　ことを特徴とする請求の範囲第１項に記載の情報生成装置。     An auxiliary encoding means for adding an error correction code to the auxiliary data;
    2. The information generation according to claim 1, wherein the replacement unit generates replacement user data by replacing a part of the encoded data with auxiliary data to which the error correction code is added. apparatus.
  4. 　前記補助データによって、前記ユーザデータを暗号化することで暗号化されたユーザデータを生成する暗号化手段を更に備え、
    　前記符号化手段は、前記暗号化されたユーザデータに対して誤り訂正符号を付加して、符号化データを生成し、
    　前記位置情報生成手段は、前記位置情報を、前記暗号化されたユーザデータに基づいて生成する
    　ことを特徴とする請求の範囲第１項に記載の情報生成装置。     And further comprising encryption means for generating encrypted user data by encrypting the user data with the auxiliary data,
    The encoding means generates an encoded data by adding an error correction code to the encrypted user data,
    The information generation apparatus according to claim 1, wherein the position information generation unit generates the position information based on the encrypted user data.
  5. 　前記位置情報生成手段は、前記位置情報を、前記ユーザデータに加えて鍵情報に基づいて生成することを特徴とする請求の範囲第１項に記載の情報生成装置。 2. The information generating apparatus according to claim 1, wherein the position information generating means generates the position information based on key information in addition to the user data.
  6. 　前記位置情報を用いて、前記補助データを変更する補助データ変更手段を更に備えることを特徴とする請求の範囲第１項に記載の情報生成装置。 The information generation apparatus according to claim 1, further comprising auxiliary data changing means for changing the auxiliary data using the position information.
  7. 　ユーザデータの一部を、前記ユーザデータに関連するデータであって、前記ユーザデータとは異なる用途で用いられる補助データに置換して、置換ユーザデータを生成する情報生成装置であって、
    　前記ユーザデータに対して誤り訂正符号を付加して、符号化データを生成する符号化手段と、
    　前記補助データを変更補助データに変更するための変更情報を、前記ユーザデータに基づいて生成する変更情報生成手段と、
    　前記変更情報を用いて、前記補助データを変更補助データに変更する補助データ変更手段と、
    　前記符号化データの一部を、前記変更補助データに置換して、前記置換ユーザデータを生成する置換手段と
    　を備えることを特徴とする情報生成装置。     An information generation device that generates replacement user data by replacing a part of user data with auxiliary data that is related to the user data and is used for a different purpose from the user data,
    Encoding means for generating encoded data by adding an error correction code to the user data;
    Change information generating means for generating change information for changing the auxiliary data to change auxiliary data based on the user data;
    Auxiliary data changing means for changing the auxiliary data to change auxiliary data using the change information;
    An information generating apparatus comprising: replacement means for generating a replacement user data by replacing a part of the encoded data with the change auxiliary data.
  8. 　請求の範囲第１項に記載の情報生成装置によって生成された置換ユーザデータが記録されていることを特徴とする記録媒体。 A recording medium in which replacement user data generated by the information generating device according to claim 1 is recorded.
  9. 　請求の範囲第７項に記載の情報生成装置によって生成された置換ユーザデータが記録されていることを特徴とする記録媒体。 A recording medium on which replacement user data generated by the information generating device according to claim 7 is recorded.
  10. 　請求の範囲第１項に記載の情報生成装置によって生成された置換ユーザデータを再生する情報再生装置であって、
    　前記置換ユーザデータを、前記誤り訂正符号を用いて、前記ユーザデータに復号する復号手段と、
    　前記位置情報を、前記復号されたユーザデータに基づいて生成する第２位置情報生成手段と、
    　前記第２位置情報生成手段によって生成された前記位置情報に基づいて、前記置換ユーザデータから前記補助データを抽出する抽出手段と
    　を備えることを特徴とする情報再生装置。     An information reproduction device for reproducing replacement user data generated by the information generation device according to claim 1,
    Decoding means for decoding the replacement user data into the user data using the error correction code;
    Second position information generating means for generating the position information based on the decoded user data;
    An information reproducing apparatus comprising: extraction means for extracting the auxiliary data from the replacement user data based on the position information generated by the second position information generation means.
  11. 　請求の範囲第７項に記載の情報生成装置によって生成された置換ユーザデータを再生する情報再生装置であって、
    　前記置換ユーザデータから、前記変更補助データを抽出する抽出手段と、
    　前記置換ユーザデータを、前記誤り訂正符号を用いて、前記ユーザデータに復号する復号手段と、
    　前記変更情報を、前記復号されたユーザデータに基づいて生成する第２変更情報生成手段と、
    　前記第２変更情報生成手段によって生成された前記変更情報に基づいて、前記変更補助データを前記補助データに再変更する再変更手段と
    　を備えることを特徴とする情報再生装置。     An information reproduction device for reproducing replacement user data generated by the information generation device according to claim 7,
    Extraction means for extracting the change auxiliary data from the replacement user data;
    Decoding means for decoding the replacement user data into the user data using the error correction code;
    Second change information generating means for generating the change information based on the decrypted user data;
    An information reproducing apparatus comprising: a re-changing unit that re-changes the change auxiliary data into the auxiliary data based on the change information generated by the second change information generating unit.
  12. 　ユーザデータの一部を、前記ユーザデータに関連するデータであって、前記ユーザデータとは異なる用途で用いられる補助データに置換して、置換ユーザデータを生成する情報生成方法であって、
    　前記ユーザデータに対して誤り訂正符号を付加して、符号化データを生成する符号化工程と、
    　前記符号化データにおける前記補助データに置換されるデータの位置を示す位置情報を、前記ユーザデータに基づいて生成する位置情報生成工程と、
    　前記符号化データの一部を、前記位置情報に基づいて前記補助データに置換して、前記置換ユーザデータを生成する置換工程と
    　を備えることを特徴とする情報生成方法。     An information generation method for generating a replacement user data by replacing a part of user data with auxiliary data used in a use different from the user data, which is related to the user data,
    An encoding step of generating encoded data by adding an error correction code to the user data;
    A position information generating step for generating position information indicating a position of data to be replaced with the auxiliary data in the encoded data based on the user data;
    A replacement step of replacing a part of the encoded data with the auxiliary data based on the position information to generate the replacement user data.
  13. 　ユーザデータの一部を、前記ユーザデータに関連するデータであって、前記ユーザデータとは異なる用途で用いられる補助データに置換して、置換ユーザデータを生成する情報生成方法であって、
    　前記ユーザデータに対して誤り訂正符号を付加して、符号化データを生成する符号化工程と、
    　前記補助データを変更補助データに変更するための変更情報を、前記ユーザデータに基づいて生成する変更情報生成工程と、
    　前記変更情報を用いて、前記補助データを変更補助データに変更する補助データ変更工程と、
    　前記符号化データの一部を、前記変更補助データに置換して、前記置換ユーザデータを生成する置換工程と
    　を備えることを特徴とする情報生成方法。     An information generation method for generating a replacement user data by replacing a part of user data with auxiliary data used in a use different from the user data, which is related to the user data,
    An encoding step of generating encoded data by adding an error correction code to the user data;
    A change information generating step for generating change information for changing the auxiliary data to change auxiliary data based on the user data;
    Using the change information, an auxiliary data changing step for changing the auxiliary data to change auxiliary data;
    A replacement step of generating a replacement user data by replacing a part of the encoded data with the change auxiliary data.
  14. 　請求の範囲第１２項に記載の情報生成方法によって生成された置換ユーザデータを再生する情報再生方法であって、
    　前記置換ユーザデータを、前記誤り訂正符号を用いて、前記ユーザデータに復号する復号工程と、
    　前記位置情報を、前記復号されたユーザデータに基づいて生成する第２位置情報生成工程と、
    　前記第２位置情報生成工程において生成された前記位置情報に基づいて、前記置換ユーザデータから前記補助データを抽出する抽出工程と
    　を備えることを特徴とする情報再生方法。     An information reproduction method for reproducing replacement user data generated by the information generation method according to claim 12,
    A decoding step of decoding the replacement user data into the user data using the error correction code;
    A second position information generating step for generating the position information based on the decoded user data;
    An information reproducing method comprising: an extracting step of extracting the auxiliary data from the replacement user data based on the position information generated in the second position information generating step.
  15. 　請求の範囲第１３項に記載の情報生成方法によって生成された置換ユーザデータを再生する情報再生方法であって、
    　前記置換ユーザデータから、前記変更補助データを抽出する抽出工程と、
    　前記置換ユーザデータを、前記誤り訂正符号を用いて、前記ユーザデータに復号する復号工程と、
    　前記変更情報を、前記復号されたユーザデータに基づいて生成する第２変更情報生成工程と、
    　前記第２変更情報生成工程において生成された前記変更情報に基づいて、前記変更補助データを前記補助データに再変更する再変更工程と
    　を備えることを特徴とする情報再生方法。     An information reproduction method for reproducing replacement user data generated by the information generation method according to claim 13,
    An extraction step of extracting the change auxiliary data from the replacement user data;
    A decoding step of decoding the replacement user data into the user data using the error correction code;
    A second change information generating step for generating the change information based on the decrypted user data;
    A re-change step of re-changing the change auxiliary data to the auxiliary data based on the change information generated in the second change information generation step.
PCT/JP2008/059930 2008-05-29 2008-05-29 Information generating equipment and method, information reproduction equipment and method, and recording medium WO2009144802A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/JP2008/059930 WO2009144802A1 (en) 2008-05-29 2008-05-29 Information generating equipment and method, information reproduction equipment and method, and recording medium

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP2008/059930 WO2009144802A1 (en) 2008-05-29 2008-05-29 Information generating equipment and method, information reproduction equipment and method, and recording medium

Publications (1)

Publication Number Publication Date
WO2009144802A1 true WO2009144802A1 (en) 2009-12-03

Family

ID=41376701

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2008/059930 WO2009144802A1 (en) 2008-05-29 2008-05-29 Information generating equipment and method, information reproduction equipment and method, and recording medium

Country Status (1)

Country Link
WO (1) WO2009144802A1 (en)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11213554A (en) * 1997-11-20 1999-08-06 Toshiba Corp Copy preventing device
JP2000057058A (en) * 1998-08-05 2000-02-25 Toshiba Corp Data reproducing device, data recording device and program recording medium
JP2000224411A (en) * 1999-01-26 2000-08-11 Internatl Business Mach Corp <Ibm> Method for adding additional message to digital message and computer system
JP2003198831A (en) * 2001-12-26 2003-07-11 Toshiba Corp Signal processing method and apparatus, signal reproduction processing apparatus and method, and recording medium

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11213554A (en) * 1997-11-20 1999-08-06 Toshiba Corp Copy preventing device
JP2000057058A (en) * 1998-08-05 2000-02-25 Toshiba Corp Data reproducing device, data recording device and program recording medium
JP2000224411A (en) * 1999-01-26 2000-08-11 Internatl Business Mach Corp <Ibm> Method for adding additional message to digital message and computer system
JP2003198831A (en) * 2001-12-26 2003-07-11 Toshiba Corp Signal processing method and apparatus, signal reproduction processing apparatus and method, and recording medium

Similar Documents

Publication Publication Date Title
US7536727B2 (en) Content management method, recording and/or reproducing apparatus, and recording medium
KR100730546B1 (en) Content management method and recording medium
JP3779580B2 (en) Signal processing method and apparatus, signal reproduction method and apparatus, and recording medium
KR19990063546A (en) Method and apparatus for protecting copyright of digital record carrier, and digital record carrier
US20090276635A1 (en) Controlling distribution and use of digital works
US20080320318A1 (en) Method and apparatus for data encryption and decryption
KR100597987B1 (en) Modulator, modulation method, and method for manufacturing an optical recordable medium with enhanced security for confidential information
EP2270786B1 (en) Information recording processing apparatus, information reproduction processing apparatus, information recording processing method, and information reproduction processing method
JP2005196926A (en) Recording medium, recording medium writing device, recording medium reading device, recording medium writing method and recording medium reading method
JP3972879B2 (en) Information recording processing apparatus, information reproducing processing apparatus, information recording medium and method, and computer program
JP3735591B2 (en) Signal processing apparatus, signal processing method, and storage medium
WO2009144802A1 (en) Information generating equipment and method, information reproduction equipment and method, and recording medium
JP3965961B2 (en) Recording medium, recording method, recording apparatus, reproducing method, and reproducing apparatus
KR100734385B1 (en) Data processing apparatus, data recording apparatus, data playback apparatus, and data storage method
US20050254387A1 (en) Recording medium processing device
JP3982488B2 (en) Information recording processing apparatus, information reproducing processing apparatus, information recording medium and method, and computer program
US8014522B2 (en) Optical storage media and the corresponding cryptography for data encryption thereof
JP4220431B2 (en) Modulation device, recording medium recording device, and recording medium
WO2011096344A1 (en) Information recording device, information reproducing device, information reproducing method, and information recording method
JP3982489B2 (en) Information recording processing apparatus, information reproducing processing apparatus, information recording medium and method, and computer program
JP3941764B2 (en) Information recording processing apparatus, information reproducing processing apparatus, information recording medium and method, and computer program
JP4751632B2 (en) Image forming apparatus
JP2005085424A (en) Information recording processing device, information reproduction processing device, information recording medium, method and computer program
JP2010008899A (en) Method of confirming drive unique key, and optical disk recording/reproducing apparatus
JP2005339740A (en) Signal generating device, signal reproducing device, recording medium processing device, signal generating method, signal reproducing method and recording medium

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 08776992

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 08776992

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: JP