Record medium, record medium manufacturing device, computer readable record medium on which program is recorded, and data presentation device

The present invention relates to a record medium on which original data (there are two cases of an original data which becomes record target to the record medium and an original data which becomes a presentation target from the record medium when a term "original data" is used in the specification) is recorded, and a record medium which is distinguishable to a record medium on which a copy data from the record medium is recorded, especially, to a record medium capable of preventing an unauthorized copy of the original data, a record medium manufacturing device, a computer readable record medium on which a program is recorded and a data presentation device which presents the record medium.

Various record media to store the digital data of the multimedia data are developed in recent years. If data is copied from the digital record medium, the record medium on which the same data as original data is copied is achieved. Therefore, it is important to prevent an unauthorized copy surely to protect a copyright, and in addition, to develop a technology and a market which use the medium by which various contents from the copyright holder.

For example, conventionally, in the digital record media such as a DAT (Digital Audio Tape) and an MD (Mini Disc), a technology which can perform only once (first generation) digital copy is provided, besides a general medium in which a copy is completely permitted (copy freely).

These technologies are called CGMS (Copy Generation Management System) and SCMS (Serial Copy Management System), and has a mechanism that a twice copy (second generation) from the medium manufactured by the copy from the medium to which only the first generation copy is permitted cannot be manufactured. As a result, an unauthorized copy is prevented.

In CGMS and SCMS, information of whether it is a copied medium (Whether a copy of a next generation can be performed or not?) is shown by a flag information in two bits.

However, in such CGMS and SCMS, it is comparatively easy to falsify this on the transmission line when the flag information is transmitted with the main body of contents. Therefore, there is a problem that an unauthorized copy may be performed by the falsification of the flag information, the medium which it is copied without authorization and is generally called as a piracy edition can circulate.

An object of the present invention is to provide a record medium, a record medium manufacturing device, a computer readable record medium on which a program is recorded in which it can be judged whether a digital data recorded in the record medium is an original data or a copied data, and an unauthorized data copy can be prevented, and, in addition, a data presentation device which presents the record medium.

A record medium of the present invention comprises an original data obtained by superimposing a presentation target data, to which an error correction encoding is performed, and an identification information.

In the present invention, an original data in which a presentation target data and an identification information are superimposed is stored in the record medium. The identification information disappears by the error correction processing when the original data is taken out and is presented, and the presentation data becomes different data from the original data. That is, the identification information is forcibly embedded into the original data as an error data in the present invention. This superimposed identification information is a frequency of the extent surely removed by the error correction processing.

It can be judged whether or not the record medium stores the original data, if the identification information is taken out before the error correction processing is preformed. Therefore, the record medium in which whether the recorded digital data is an original data or a copied data can be judged, and an unauthorized data copy can be prevented can be provided.

The preferred manners of the above-mentioned record medium are as follows. <ul id="ul0001" list-style="none" compact="compact"><li>(1) The identification information has a plurality of partial identification informations, and the plurality of partial identification informations are separately superimposed to a plurality of positions in the presentation target data to which the error correction encoding is performed. The identification information can become sufficiently long, and the data reliability can be improved. In addition, safety can be improved since the identification information is distributed to be embedded in the original data.</li><li>(2) The identification information is superimposed to a data part stored in an area where a control information of contents data in a record area is recorded. With this configuration, change of the identification information by the third party can be prevented after the record medium is manufactured.</li><li>(3) An information to acquire a superimposed position of the identification information is further provided. It makes easy and certain to take out the identification information.</li><li>(4) The identification information has a plurality of partial identification informations, an information to acquire a superimposed position of the identification information has an initial value information, a superimposed position information indicating a superimposed position of the plurality of partial identification informations, and a plurality of position informations to acquire a position of the superimposed position information, a first position information to acquire the position of the superimposed position information is recorded at a position obtained by converting the initial value information by a predetermined function or a position shown by a position obtained as a result of the conversion, and a second or later position information is recorded in another position of the position obtained by converting a storage information of a position of a result when an information stored at another position of a side where the position information is not stored is further converted by the predetermined function in any positions obtained by a conversion result of the predetermined function, or a storage information at a position indicated to a position of a result of conversion one by one. Since such means is provided, a concealment of the position information and the superimposed position information can be improved besides the similar function and advantage to (3) is achieved.</li><li>(5) The identification information has a plurality of partial identification informations, an information to acquire a superimposed position of the identification information has an initial value information, a superimposed position information indicating a superimposed position of the plurality of partial identification informations, and a plurality of position informations to acquire a position of the superimposed position information, an initial position information is recorded at a position obtained by converting the initial value information by a predetermined function or a position shown by a position obtained as a result of conversion by the predetermined conversion formula, and a position information after that is recorded at a position based on a data recorded by a predetermined distance at a position indicated by a position information obtained immediately before or a distance obtained by a predetermined conversion formula, or a position obtained by converting a position information obtained immediately before by a predetermined conversion formula. Since such means is provided, a concealment of the position information and the superimposed position information can be improved besides the similar function and advantage to (3) is achieved.</li><li>(6) A superimposed position of the identification information is given by a table form. Since such means is provided, a concealment of the position information and the superimposed position information can be improved besides the similar function and advantage to (3) is achieved.</li><li>(7) The presentation target data is scrambled or encrypted to make the identification information a key before an error correction encoding is performed. Since such means is provided, fair data presentation cannot be performed if the scramble or the encryption cannot be released by taking out the identification information as a key when the presentation target data is presented. Thus, an unauthorized copy to the presentation target data can be prevented.</li></ul>

Of course, the present invention can be applied also to a record medium manufacturing device to manufacture the above-mentioned record medium and the undermentioned data presentation device which presents the data recorded in the record medium manufactured with the manufacturing device for example.

The data presentation device of the present invention comprises an identification information decoding means to extract identification information from a read information before a read original data from one of above-mentioned record media is error-corrected, and judgement means to judge whether or not data stored in the record medium is an original data based on the identification information extracted by the identification information decoding means and output a judgement result. Since such means is provided, whether or not data stored in the record medium is an original record, in addition, a record medium is an original record medium can be judged, and the judgment result is output. If this judgment result of the output is used, the prevention of an unauthorized copy and the generation management of data copy etc. can be easily performed.

Moreover, the data presentation device which presents the data recorded on the record media from (1) to (7) can be achieved as well as the above-mentioned. The same advantage as the above-mentioned record medium can be achieved according to such a data presentation device.

In addition, the record medium on which a control program to achieve the function of the above-mentioned record medium manufacturing device and the data presentation device in the computer is recorded can be achieved, and, in that case, a similar advantage to the above-mentioned can be obtained. For example, the following record media can be achieved.

For example, a computer readable record medium on which a program for the computer to function is recorded, comprises a program which executes: error correction encoding means for encoding a presentation target data by error-correcting code; and identification information superimposed means for superimposing an identification information to the presentation target data in which an error correction encoding by the error correction encoding means. Here, a program for scrambling and encrypting the presentation target data making the identification information a key, and executing scramble/encrypting means for delivering it to error correction encoding means is further provided.

Moreover, a computer readable record medium on which a program for the computer to function is recorded, comprises a program which executes: identification information decoding means for extracting an identification information from a read information before an original data read from the above-mentioned record medium is error-corrected; judgment means for judging whether a data stored in the record medium based on an identification information extracted to the identification information decoding means is an original data, and for outputting a judgment result. A computer readable record medium on which a program for the computer to function is recorded, comprises a program which executes: identification information decoding means for extracting an identification information from a read information before an original data read from the above-mentioned record medium is error-corrected; data presentation means for unscrambling or decrypting the presentation target data which is scrambled or decrypted in which an identification information extracted to the identification information decoding means is made as a key.

As described above in detail, according to the present invention, since the identification information is superimposed to the presentation target data which is error-correcting-coded and the result thereof is made to an original data, a record medium, a record medium manufacturing device, a data presentation device, and a computer readable record medium on which a program is recorded, in which it can be judged whether a digital data recorded in the record medium is an original data or a copied data, and an unauthorized data copy can be prevented.

This summary of the invention does not necessarily describe all necessary features so that the invention may also be a sub-combination of these described features.

The invention can be more fully under stood from the following detailed description when taken in conjunction with the accompanying drawings, in which: <ul id="ul0002" list-style="none" compact="compact"><li>FIG. 1 is a block diagram which shows an example of a main configuration of the record medium manufacturing device according to the first embodiment of the present invention;</li><li>FIG. 2 is a figure to explain an outline idea of the error correction;</li><li>FIG. 3 is a figure to explain the principle of preventing an original data from copy with taking out the identification information M of the original data by using the error correction processing;</li><li>FIG. 4 is a block diagram which shows an example of a main configuration of the record medium manufacturing device according to the second embodiment of the present invention;</li><li>FIG. 5 is a block diagram which shows an example of a main configuration of the data presentation device of the embodiment;</li><li>FIG. 6 is a figure to explain an operation of the data block and the identification information decoder;</li><li>FIG. 7 is a figure to explain the configuration of the data block and an operation of the identification information decoder in the third embodiment of the present invention;</li><li>FIG. 8 is a block diagram which shows an example of a main configuration of the data presentation device of the fourth embodiment of the present invention;</li><li>FIG. 9 is a figure to explain the configuration of the information storage table and a method of acquiring superimposed position information of partial identification information according to the embodiment;</li><li>FIG. 10 is a figure to explain the configuration of the information storage table and a method of acquiring superimposed position information of partial identification information according to the fifth embodiment of the present invention;</li><li>FIG. 11 is a block diagram which shows an example of a main configuration of the record medium manufacturing device of the sixth embodiment of the present invention; and</li><li>FIG. 12 is a block diagram which shows an example of a main configuration of the data presentation device of the embodiment.</li></ul>

Hereinafter, the embodiments of present invention will be explained.

(First Embodiment)

A method of embedding the identification information in the main body of data of the digital record medium by using the error correction technology in the first embodiment will be explained.

FIG. 1 is a block diagram which shows an example of a main configuration of the record medium manufacturing device according to the first embodiment of the present invention.

The record medium manufacturing device shown in FIG. 1 has an A/D converter 1, an error correction encoder 2, and an identification information superimposition circuit 3, and these circuits relate to the embedded part of the identification information in which the error correction technology is used. The explanation about a general configuration part which affects manufacturing the record medium will be omitted.

The record medium 4 manufactured here is a disc which is a readable and readable/recordable medium such as a DVD (Digital Video Disc, Digital Versatile Disc)-ROM, DVD-RAM, MD, CD, CD-ROM, and CD-R, etc., and an original record medium on which the multimedia data such as documents, audio, still pictures, and the motion images, etc. are recorded.

In the first embodiment, the original record medium 4 is manufactured as the identification information M stored only in the original record medium disappears when the data taken out from the original record medium 4 is recorded on other record media.

As the component for that, first, the error correction encoder 2 makes the digital data 7 which is contents an error correction encoding, and generates the main body 8 of data stored in the record medium 4. On the other hand, the identification information superimposition circuit 3 embedds the identification information M in a part of the main body 8 of data, and outputs the corresponding data to the record medium 4.

Next, an operation of record medium manufacturing device as mentioned above constructed according to the first embodiment will be explained.

First, the digital contents 5 and the analog contents 6 of the multimedia data to be recorded on the original record medium 4 are prepared. Where, in case of an analog data, first, a sampling and a quantization are performed in the A/D converter 1 and the data is converted into the digital data 7.

An appropriate error correction encoding is performed to the digital data 7 which consists of the digital contents 5 or the analog contents 6 to which the A/D conversion is performed in the error correction encoder 2 to correct the error occurring in the transmission line, and the main body 8 of data is obtained.

Next, the identification information superimposition circuit 3 superimposes the identification information M to a part of a symbol of the digital data (main body 8 of data) to which an error correction encoding is performed. When it is expected the error is embedded to the identification information M, the identification information to be added is made an error correction encoding beforehand. As a result, the identification information is divided into an appropriate size (byte unit etc.) when it becomes long, and is made as partial identification informations M1, M2, ···, Mi, ···, Mn, respectively. The identification information M shown in FIG. 1 is the information to which an error correction encoding is performed beforehand like this.

The main body 9 of the identification information superimposed data obtained thus is stored in the record medium 4 as an original data, and the disc manufacturing is completed.

Therefore, the identification information M (partial identification informations M1, ···, Mn) is embedded under a part of the digital data (main body 8 of data) to which an error correction encoding is performed as shown in FIG. 1 in a predetermined position in all data in the record medium 4 or the data for every data block with constant size. Each of the partial identification information Mi actually is distributed in the data block and is embedded as shown in FIG. 1. The data where the identification information M is embedded is the original data of the record medium 4.

A method of fairly taking out the digital data 7 which is contents of the record medium 4 manufactured like this and a method of taking out the identification information M, and preventing an unauthorized copy of the original data will be explained.

FIG. 2 is a figure to explain an outline idea of the error correction.

FIG. 3 is a figure to explain the principle of preventing from the copy of the original data when the identification information M is taken out from the original data by using the error correction processing. The error correction technology shown in FIG. 2 and FIG. 3 is extremely simplified for the convenience of the explanation, and an actual error correction technology is more complex.

First, the data error is occurred by the bit inversion at a data reading from the record medium and a data transmission as shown in FIG. 2(a). It is a basic idea to perform the error correction for giving redundancy to the data to present accurate data even if such a bit inversion occurs (FIG. 2(b)).

For this reason, some bit inversions are occurred even if the redundant data for the error correction is added to real contents data, and real contents data can be presented (for example, FIG. 2(c)). The processing is the error correction encoding processing in the error correction encoder 2 shown in FIG. 1. Therefore, when the data error is gotten into the data that an error correction encoding processing is performed, data including the error is presented to the data with no error before the error is gotten into by the error correction decoder in the data presentation device.

The present invention pays attention to this respect. The present invention is an invention to record the information which is considered as an error data in the above-mentioned error correction technology on the record medium 4 as the identification information M. That is, the identification information superimposition circuit 3 according to the present invention superimposes the identification information M in a form considered to be an error data into the main body of data in the data presentation device which presents the record medium 4. This superimposition is achieved to embed the identification information M to a part of data of the main body 8 of data at low frequency of extent to which the error correction can be performed enough by the error correction decoding. Therefore, when the part where the identification information M is superimposed as shown in FIG. 2(d) also is presented by the data presentation device such as DVD players, it is presented as a data (digital data 7) before the identification information M is superimposed by the error correction function.

The presentation (data output) of original record medium 4 manufactured thus will be explained referring to FIG. 3. Here, two cases that a part where identification information M is embedded and a part not so will be explained.

The original record medium 4 is set to the data presentation devices such as a DVD-RAM drive and a player, and reading the data on the record medium and the output of the read data are performed.

A part of bit of the read data reverses about the part (FIG. 3(a)) where the identification information M is not superimposed if there is a read error when data is read from the record medium. However, the reversed error data is corrected, and output as the same data as real digital data 7 by a usual error correction decoding processing 10.

Next, a case of occurring an error and not occurring an error will be explained when the data is read out from the record medium at a part where the identification information M is superimposed (FIG. 3(b)).

First, a case of occurring no error at the time of reading data of the record medium (FIG. 3(b-1)).

The identification information M is embedded in the original data of the original record medium 4 beforehand as the data error. The identification information M is considered an error data and is corrected by the error correction decoding processing 10 when this is read, and the same data as the real digital data 7 is output. This output data is a data corresponding to the real contents data. Therefore, the data presentation is fairly performed. However, this output data is not the same data as the original data of the original record medium 4. The reason is why the identification information M in the original data has been deleted by the error correction. Therefore, when this output data is copied, the copy data becomes a data different from the original data. In the following data presentations, an unauthorized copy can be prevented by using the difference point thereof. When the identification information M is taken out and used, the identification information is extracted after reading from the record medium 4 and before performing the error correction.

Next, a case of occurring the read error of the record medium when the part where the identification information M is superimposed is presented (FIG. 3(b-2)).

In this case, an output data is corrected as well as each above-mentioned case (FIG. 3(a) and FIG. 3(b-1)) and the same data as the digital data 7 is output. On the other hand, the data error should be included in the identification information extracted in this case. Then, if the error correction processing is performed to the identification information which includes this error, a first identification information M will be taken out. Though an identification information is short in the example of FIG. 3 for the convenience of the explanation, when the error correction processing is performed to the identification information, this identification information M becomes a long enough as described above. Specifically, the error correction is performed as follows. Error correction and data presentation of the identification information superimposed data are performed by the error correction decoding. Here, when an error data is occurred in the identification information and read information/transmission line, further error correction is performed.

The identification information which indicates that it is an original record medium in the data made an error correction encoding is superimposed to the record medium according to the embodiment of the present invention as an error like the above-mentioned. Therefore, it can be judged whether it is an original record medium by extracting the identification information before the processing of the error correction decoding when presenting.

Moreover, in the data presentation device, since the identification information is processed as an error after the error correction decoding processing completes, a real digital data is correctly decoded. Therefore, it becomes possible to clearly distinguish the record medium manufactured by the copy from the original record medium since the identification information which indicates that it is original data is missed when the presentation data is copied onto another record medium.

Therefore, it is possible to surely distinguish the medium manufactured by the copy from the original record medium since the copy management information is not transmitted on the transmission line with the presentation target data as the conventional ones. In addition, an unauthorized copy and an unauthorized use of the data become very difficult since it is difficult for a general user to superimpose the identification information to the data in which an error correction encoding is performed.

In addition, since the identification information consists of the partial identification information, by distributing and superimposing this to the main body 8 of data, the concealment of the identification information and safety can be improved, and the data length can become long enough. Therefore, it is possible to adopt a configuration which an error correction encoding is performed in the identification information extracted for example, and the reliability of the identification information can be improved.

The record medium manufacturing device to manufacture the above-mentioned record medium can manufacture the record medium like the above-mentioned by providing the identification information superimposition circuit.

(Second Embodiment)

A mechanism to specify superimposed positions of the superimposed identification information M in the record medium 4 in the first embodiment will be explained in each of following embodiments.

In this embodiment, a record medium manufacturing device and a data presentation device which embed the superimposed position specification information in the main body of data in addition to the identification information M when manufacturing the record medium will be explained.

FIG. 4 is a block diagram which shows an example of a main configuration of the record medium manufacturing device according to the second embodiment of the present invention, and the same reference numeral is used to the same part as FIG. 1 and an explanation will be omitted.

This record medium manufacturing device is constructed similar to the first embodiment besides being constructed for the identification information superimposition circuit 3b to superimpose the identification information M in the main body 8 of data as well as the identification information superimposition circuit 3, and to generate the original data 9b adding the superimposed position specification information of the identification information to the main body of data where this identification information M is added. The superimposed position specification information is not superimposed to the main body of data but is added as additional data.

The record medium 4b is manufactured by storing the original data 9b produced thus.

On the other hand, FIG. 5 is a block diagram which shows an example of a main configuration of the data presentation device of this embodiment.

This data presentation device demodulates an error-corrects data D1 and D2 read from the record medium 4b by a disc read part (not shown) with the demodulation/error correction decoder 11, and presents and outputs through the data output controller 12.

When it is judged the identification information output from the identification information decoder 13 is not right with the identification information judgment circuit 14, the data output controller 12 stops the presentation/output according to the control signal from the identification information judgment circuit 14.

The identification information decoder 13 has the superimposed position specification circuit 15 and the identification information extraction circuit 16.

The superimposed position specification circuit 15 decodes the superimposed position of the identification information in the data block based on the superimposed position specification information from the record medium 4b, and specifies the decoded superimposed position for the identification information extraction circuit 16. This superimposed position specification information is an information which is read from the record medium 4b by the disc read part (not shown), and, in addition, demodulated and error-corrected by the demodulator/error correction decoder 17.

The identification information extraction circuit 16 reads data sections to specify the superimposed position from the record medium through the disc read part, extracts the identification information M (or, partial identifying information Mi), and sends it to the identification information judgment circuit 14. In addition, since the data of the remainder to which the identification information is extracted is a part of the main body 8 of data in FIG. 1, this is input to the demodulator/error correction decoder 11 as data D2.

Next, an operation of the record medium manufacturing device and data presentation device of the embodiment as mentioned above constructed will be explained.

First, a manufacturing process of the record medium 4 will be explained.

It is similar to the first embodiment until the digital data 7 from the analog contents 6 or the digital contents 5 in FIG. 4 become the main body 8 of data in which an error correction encoding is performed.

Next, the identification information M is superimposed to the position based on the superimposed position specification information for the main body 8 of data by the identification information superimposition circuit 3b. The superimposed identification information M is similar to the first embodiment in the point which it is the enough to long to be able to perform the error correction, and is divided into the partial identification information Mi. Moreover, to improve the reliability of the identification information M, a lot of same identification information may be superimposed.

In addition, the superimposed position specification information is added to the main body 8 of data to which the identification information M is superimposed. This added superimposed position specification information is performed an error correction encoding as well as other contents digital data. The superimposed position specification information can be added before superimposition of the identification information M. The superimposed procedure of the identification information when the disc is manufactured is performed to correctly operate the identification information extraction described later.

The data block which consists of main body 8 of data to which the identification information M is superimposed and the superimposed position specification information is produced. In the data block, a lot of blocks may be stored in one record medium 4b, and one block may correspond to one record medium 4b. Even in any case, the data which is produced with the above-mentioned identification information superimposition circuit 3b and should be stored in the record medium 4b is the original data 9b.

Consequently, the original data 9b is stored in the medium and the record medium 4b is completed.

Next, the data presentation from this record medium 4b will be explained.

First, the record medium 4b which consists of the disc such as a DVD is set in the data presentation device as shown in FIG. 5. An encryption technology for the unauthorized copy prevention has already been introduced in the DVD. The explanation of an existing protection technology will be omitted in this embodiment. The contents are protected with two kinds of encoding keys in the DVD according to the prior art, and whether contents are encoded is not described in this embodiment. Naturally, this embodiments can be adopted to these existing protection technologies.

The superimposed position specification information is read from the set DVD disc at the first data reading in each data block. After the demodulation and the error correction decoding processing are performed in the demodulator/error correction decoder 17, this superimposed position specification information is delivered to the superimposed position specification circuit 15.

The superimposed position specification circuit 15 obtains the position where the identification information M in the data is superimposed based on a received superimposed position specification information. This superimposed position is delivered to the identification information extraction circuit 16.

The main body part of data which corresponds to contents (data D1) is read out, and the error correction is performed and the presentation data is output through the demodulator/error correction decoder 11 and the data output controller 12. On the other hand, the identification information M is added under the main body part of data, and the read data is delivered to the identification information extraction circuit 16 not to the demodulator/error correction decoder 11 when the embedded part is read. This is achieved since the identification information extraction circuit 16 acquires the embedded position of the identification information M from the embedded position specification circuit 15.

The corresponding identification information M is extracted from data (D2 + M) which includes the identification information M (partial identification information Mi in reading once), and data D2 is sent to the demodulator/error correction decoder 11 and is presented and output like as the data D1.

The identification information extraction circuit 16 performs the error correction when the whole of the identification information M which consists of the partial identification information Mi is obtained, sends the result (identification information M) to the identification information judgment circuit 14. The identification information M is extracted at first of the data block reading in the chain in this embodiment as described later.

The identification information judgment circuit 14 verifies the validity of extracted identification information M, the control signal is output to the data output controller 12 and reading and the presentation of the data are stopped when it is unauthorized.

The identification information M has disappeared from the presentation data since above-mentioned data D1 and D2 (D2 may be D2 + M) output the presentation data through the demodulator/error correction decoder 11 even though the identification information M is right. Therefore, even if this presentation data is copied by any means, the identification information M cannot be extracted from the copy record medium to which the copy data is stored different from the record medium 4b to which the original data 9b is stored. Therefore, the present invention has the advantage that an unauthorized copy can surely be prevented.

Next, specific operation of the identification information decoder 13, especially the superimposed position specification circuit 15 will be explained.

FIG. 6 is a figure to explain an operation of the data block and the identification information decoder.

This data block has the superimposed position specification information of the identification information and the main body of data to which the identification information is superimposed. The superimposed position specification circuit 15 performs the conversion processing shown in FIG. 6.

First of all, an initial value (seed) necessary for specifying the position is read from among the superimposed position specification information. And, the superimposed position specification circuit 15 converts an initial value necessary for specifying the position by using a predetermined conversion f(·), and obtains initial position information f(seed) = (x1, y1). This obtained information indicates a position in the area where the superimposed position specification information of the identification information is recorded.

Next, data q1 recorded on the position shown by the initial position information (x1, y1) is chosen by the superimposed position specification circuit 15. Data q1 is converted by a predetermined conversion g(·), and a position information g(q1) = (α1, β1) on which the identification information is superimposed. This obtained position information is delivered from the superimposed position specification circuit 15 to the identification information extraction circuit 16, and the partial identification information M1 superimposed to the specified position is extracted by the identification information extraction circuit 16.

Next, a position f(p2) = (x2, y2) where a following superimposed position specification information is recorded is obtained by the superimposed position specification circuit 15 with a predetermined distance at a position indicated by the above-mentioned initial position information (x1, y1) or a distance obtained by a predetermined conversion formula (distance is 1 in the right side in FIG. 6).

All superimposed position information is obtained by executing the above-mentioned operation repeatedly (sequentially). That is, a position information (xi ,yi) where an i-th superimposed position specification information qi is recorded is obtained by f(pi) = (xi ,yi), and a position g(qi) = (αi ,βi) where the identification information is superimposed by using the information qi which is recorded at the position is obtained. In addition, an operation of extracting the partial identification information Mi superimposed to the position is repeated sequentially until all (n pieces) partial identification informations are extracted.

In above-mentioned operation, when positions (xi, yi) and (αi, βi) which have been chosen already by the conversion f(·) and g(·) are obtained respectively, to avoid the same value being chosen every time by the operation thereafter, data recorded at the position (further right adjacent position in FIG. 6) which is adjacent in a predetermined distance from the position where the data is recorded or a distance obtained by a predetermined conversion formula is chosen again.

Since the record medium according to the embodiment of the present invention stores the superimposed position specification information besides having a similar configuration to the first embodiment as mentioned above, the identification information can be easily and certainly taken out.

Since the superimposed position of the partial identification information is stored in the superimposed position specification information to obtain through the predetermined conversion, the concealment of the superimposed position can be improved, and the identification information be safe. In addition, since this superimposed position can be taken out sequentially, taking out the identification information can be made easy.

Since the record medium manufacturing device of this embodiment comprises the identification information superimposition circuit 3b, the superimposed position specification information besides the superimposition of the identification information can be added, and above-mentioned record medium 4b can be manufactured.

In addition, since the data presentation device of this embodiment comprises the identification information decoder 13 and the identification information judgment circuit 14, an advantage based on the above-mentioned record medium 4b can be achieved, whether the data stored in the record medium in addition is original data and whether it is an original record medium can be judged, and the judgment result is output. An unauthorized copy by the data output controller 12 can be prevented by using this output judgment result.

In this embodiment, the identification information judgment circuit 14 judges only whether a set disc is the original record medium 4b which stores only the identification information M, and controls the data output. The present invention has the feature in the point that the data corresponding to contents on the original record medium can be distinguished from the copy discs. Then, by properly combining this function, and CGMS or SCMS, etc., it is also possible to construct an unauthorized copy prevention system (various data copy generation management) being ultrasafe and intelligent.

In the processing shown in FIG. 6, it is also possible to obtain the superimposed position of the partial identification information Mi by the conversion g(·) assuming the data recorded at the adjacent position to be qi after the position of pi is obtained first by conversion f(·) by replacing the relationship of the superimposed position specification information pi and qi. For example, all of only the superimposed positions of the partial identification information Mi are previously obtained and deliver to the identification information extraction circuit 16 kept together, and the identification information extraction circuit 16 may take out the identification information M according to a proper timing.

(Third Embodiment)

In the second embodiment, it is comparatively easy to presume the position where an initial value is recorded because an initial position information (x1,y1 ) is obtained by covering an initial value (seed) which is recorded at the predetermined position. This embodiment is an embodiment in which an arithmetic to obtain an initial position information becomes complicated, and the presumption of the position by the third party becomes more difficult.

FIG. 7 is a figure to explain an operation of the configuration of the data block and the identification information decoder in the third embodiment of the present invention.

That is, the record medium manufacturing device of this embodiment is constructed such as the record medium which becomes a data block shown in FIG. 7 is manufactured and data presentation device becomes executable a new conversion processing h(·). That is, the record medium manufacturing device of this embodiment manufactures the record medium which becomes a data block shown in FIG. 7, and the data presentation device is constructed that the new conversion processing h(·) becomes executable.

A superimposed position taking out processing of the identification information in this embodiment will be explained.

The disc manufacturing and the presentation procedure of the record medium in the parts other than the added conversion processing are similar to the second embodiment.

First of all, an initial value seedl necessary for specifying the position with superimposed position specification circuit 16 is read from among the superimposed position specification information, and is converted by the predetermined conversion h(·). A position (xs, ys) where the initial value seed2 used to a true position specification is recorded is obtained. Subsequently, the seed2 is converted by the conversion f(·), and an initial position information f(seed2) = (x1, y1) is obtained. An obtained information indicates a position in the area where the identification information superimposed position specification information is recorded. The following operations are similar to the second embodiment.

As described above, the record medium and the data presentation device according to the third embodiment of the present invention can improve the safety of specified information at the superimposed position and the concealment further more since the seed is converted by two stages besides a similar configuration to the second embodiment is provided.

(Fourth Embodiment)

In the fourth embodiment, a method different from the second and third embodiments as for the mechanism to specify the superimposed position in the record medium 4 of the identification information M superimposed in the first embodiment will be explained.

FIG. 8 is a block diagram which shows an example of a main configuration of the data presentation device of the fourth embodiment of the present invention.

The data presentation device according to the fourth embodiment is constructed similar to the second embodiment, besides a position information table 21 is provided in the identification information decoder 13b and the superimposed position specification circuit 15b obtains by using the superimposed position of identification information not only record medium 4b but information on position information table 21.

A superimposed position information of each partial identification information M1, M2, ···, Mn corresponding to indexes T1, T2, ···, Tm which are the superimposed position specification information are stored in a position information table 21.

FIG. 9 is a figure to explain a method of acquiring the configuration of the information storage table in the embodiment and the superimposed position information on the partial identification information.

The record medium manufacturing device and an operation of data presentation device according to this embodiment will be explained.

First, the presentation procedure of the disc manufacturing and the record medium is similar to the second embodiment. A point different from the second embodiment is that only an index Ti is added and recorded as the superimposed position specification information, and not a superimposed position of each of the partial identification information. These indexes T1, T2, ···, Tm may correspond to each of a plural kind of record media or correspond to each data block of one record medium (respectively).

When the disc is presented, this index Ti is read first, and the superimposed position pattern of the partial identification information corresponding to the index Ti is chosen from the position information table 21 in the superposed position specification circuit 15b. This superimposed position pattern is delivered from the superimposed position specification circuit 15b to the identification information extraction circuit 16, and the identification information extraction circuit 16 extracts the partial identification information Mj (j = 1, 2, ···, n) superimposed on each position.

The following processing is similar to the second embodiment.

As described above, in the record medium according to the fourth embodiment of the present invention, only the index is stored as the superimposed position specification information, a table corresponding to the index is provided in the data presentation device, and the superimposed position of the identification information can be acquired from the table based on the index. Therefore, it cannot easily know the superimposed position of the identification information only by examining the record medium since an information recorded in the record medium is only the index. Therefore, concealment of the identification information and safety can be further improved in this embodiment.

(Fifth Embodiment)

The index Ti is directly stored as the superimposed position specification information in the fourth embodiment. A seed is stored as the superimposed position specification information in place of the index Ti, and the corresponding seed is converted and the index Ti is obtained in this embodiment.

FIG. 10 is a figure to explain a configuration of the information storage table and a method of acquiring the superimposed position information of the partial identification information in the fifth embodiment of the present invention.

The data presentation device of this embodiment is constructed similar to the fourth embodiment besides a processing of performing the conversion f(·) to the seed and obtaining the index Ti is added to the superimposed position specification circuit 15b.

The record medium manufacturing device and an operation of data presentation device of this embodiment constructed like this will be explained.

First, the information seed is recorded in the record medium 4b as the identification information superimposed position specification information in place of the index Ti. When the disc is presented, this information seed is read first, and is converted by the predetermined conversion f(·) in the superimposed position specification circuit 15b to obtain the index Ti of the information storage table 21.

The following processing is similar to the fourth embodiment.

As described above, since the record medium and the data presentation device according to the embodiment of the present invention obtain the index by converting seed besides a similar configuration to the fourth embodiment is provided, safety and concealment of the specified information at the superimposed position can be further improved.

In the above-mentioned fourth and fifth embodiments, though the information storage table is stored to the data presentation device, it is also possible to store the information storage table in the record medium. In this case, encoding is performed so that the information is made as a key.

(Sixth Embodiment)

In this embodiment, means for preventing the presentation output of the unauthorized copy data by a method different from the second to the fifth embodiments will be explained.

FIG. 11 is a block diagram which shows an example of a main configuration of the record medium manufacturing device according to the sixth embodiment of the present invention, and the same reference numeral is attached to the same part of FIG. 4 and the explanation will be omitted.

This record medium manufacturing device is constructed similar to the second embodiment besides a scrambler 30 is provided.

The scrambler 30 scrambles the digital data in which the identification information M is made as the key of the scramble, outputs the scramble data 25, and delivers it to the error correction encoder 2.

On the other hand, FIG. 12 is a block diagram which shows an example of a main configuration of the data presentation device of this embodiment, and the same reference numeral is attached to the same part of FIG. 5 and the explanation will be omitted.

This data presentation device is constructed similar to the second embodiment, besides the unscrambler 31 is provided in place of the data output controller 12 and the identification information judgment circuit 14.

The unscrambler 31 unscrambles and outputs a scramble data 25 from demodulation/error correction decoder 11 as a presentation data by using the identification information M given from the identification information decoder 13.

An operation of the record medium manufacturing device and the data presentation device of this embodiment constructed as mentioned above will be explained.

In the manufacturing of the record medium 4b shown in FIG. 11, a similar processing is performed to the second embodiment excluding a processing by the scrambler 30. In the scrambler 30, the digital data 7 is scrambled by using the identification information M.

On the other hand, in the presentation of record medium 4b shown in FIG. 12, the identification information M is read first by the identification information decoder 13 similar to the second embodiment.

This read identification information M is given to the unscrambler 31. The unscrambler 31 unscrambles the scramble data 25 from the demodulation/error correction decoder 11 in which this identification information M is made a key, outputs it as a presentation data.

Here, an unscramble cannot be correctly performed and the correct data is not presented when the correct identification information cannot be decoded by the cause such as the presentation disc is a copied disc.

As described above, the record medium according to the embodiment of the present invention scrambles the digital data 7 in which the identification information is made as a key beforehand besides it has a similar configuration to the second embodiment. Therefore, fair data cannot present if the scramble cannot be released to make this a key by taking out the identification information when data is presented. Thus, an unauthorized copy to the presentation target data can be prevented.

The record medium manufacturing device to manufacture the record medium of this embodiment can manufacture the record medium in which the digital data 7 is scrambled by providing scrambler 30 besides it has a similar configuration to the second embodiment.

In addition, the data presentation device of this embodiment provides the unscrambler 31 besides it has a similar configuration to the second embodiment and unscrambles the scramble data according to the identification information. Therefore, the scramble can be released by the identification information only at time when data is presented from the regular original record medium in a case that the digital data is scrambled. Therefore, safety to an unauthorized copy can be improved.

Though a case to apply a method of scrambling the digital data 7 in which the identification information M is made a key to the second embodiment is explained in this embodiment, an application of this embodiment is not limited in this case but may be applied to any one of the first and third to fifth embodiments.

In the embodiment, a case that the digital data is scrambled is explained, the present invention is not limited to the embodiment, and, for example, a data may be encoded in place of the scramble. In this case, the data is decoded instead of the unscramble, and the identification information M becomes a code key and a decoding key.

The present invention is not limited to each of above-mentioned embodiments, and can be variously transformed within the range of the scope of the present invention.

For example, a position to which the original data is stored in each embodiment is not especially specified, the DVD and CD have an area on which a control information of the contents data is recorded and an area on which the contents data is recorded. As an example of the former, there is an area etc. where music number etc. of the CD are described. The present invention may store the original data which includes the identification information in any one of both of the above-mentioned areas.

Though, for example, each means is described in hardware, these can be all achieved even by a software means. That is, the record medium manufacturing device and the data presentation device, etc. of the embodiment comprise the computer hardware resources of a CPU and a memory, etc., and may be achieved each means of the identification information superimposition circuit and the identification information decoder, etc. of the embodiment by the control program.

Therefore, techniques described to the embodiments can be distributed by storing in storage media of, for example, the magnetic discs (floppy disc and hard disc drive, etc.), optical discs (CD-ROM and DVD, etc.), and the semiconductor memories, etc. as a program (software means) which is executable by the computer and transmitting by the communication medium. The program stored on the medium side includes a setting program which constructs the software means (including not only the execution program but also the table and the data structure) executed by the computer. The computer which achieves this device reads the program recorded in the storage medium, constructs the software means with the situation by the setting program, and executes the processing mentioned above by controlling an operation by this software means.