JP2013058965A - Digital data information embedding apparatus and embedded information detection apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a digital data information embedding apparatus capable of embedding, into original data, information to be embedded, without a loss of the original data subjected to information embedding.SOLUTION: An information embedding apparatus 10, which is configured to embed information into digital original data subjected to information embedding, comprises error correction encoding unit 1 which performs error correction encoding on the original data and outputs the original data; and an information embedding unit 2 which embeds as an error, into the original data having undergone the error correction encoding by the error correction encoding unit 1, the information to be embedded.

Description

  The present invention relates to an information embedding technique for digital data.

  Conventionally, information embedding techniques such as steganography and digital watermarking are known. For example, digital watermarks are those in which watermark information such as copyright information and certificate information is embedded in digital data such as image data, and digital watermark image data is generated by replacing a part of the image data with watermark information. Steganography uses digital data such as image data as a transmission medium (cover data) that hides embedded data.

JP 2000-174628 A

  However, the conventional information embedding technique uses an information embedding target (original data) such as image data and embeds the embedding information directly in the original content data. For example, when embedding characters in original image data, the original image data is decomposed into bit planes, and some of the bit planes are replaced with character information. There is a problem that it is difficult to completely duplicate data.

  Further, when a part of the original data is embedded with the embedded information, it is necessary to consider the data structure and complexity of the original data, and there is a problem that the embedding process is complicated.

  Therefore, the present invention provides an information embedding device for digital data that can embed embedded information in the original data without loss of the original data to be embedded, and data with embedded information embedded with the embedded information by the device. It is an object of the present invention to provide an embedded information detecting device for detecting embedded information, a program thereof, and the like.

  In order to solve the above problems, an information embedding apparatus for digital data according to the present invention performs error correction coding on original data to be embedded, and embeds embedded information as “error” in the error correction encoded original data. It is characterized by that. That is, the information embedding device of the present invention includes an error correction coding unit that performs error correction coding processing on original data, an information embedding unit that embeds embedded information as errors in the error correction coded original data, Is provided.

  An embedded information detecting apparatus according to the present invention is an apparatus for detecting embedded information from data with embedded information in which embedded information is embedded in digital original data, wherein the embedded information is embedded as an error in the data with embedded information. A restoration processing unit for restoring information is provided.

  Another aspect of the present invention is a program for embedding information in digital original data that is an information embedding target, a process for performing error correction encoding on the original data, and an error correction encoded original A process of embedding embedded information in data as an error is executed by a computer.

  Furthermore, another aspect of the present invention is a program for detecting embedded information from data with embedded information in which embedded information is embedded in original digital data, and is embedded as an error in data with embedded information. The computer is caused to execute a restoration process for restoring the embedded information.

  According to the present invention, since the original data to be embedded is subjected to error correction coding, and the embedded information is embedded as “error” in the error correction encoded original data, the original information based on the embedded information is obtained through a restoration process based on error correction. It is possible to restore the original data without any data loss and extract the embedded information.

It is a block diagram which shows 1st Embodiment of an information embedding apparatus, and is a figure explaining the process which embeds information. It is a flowchart for demonstrating operation | movement of the information embedding apparatus of 1st Embodiment. It is a block diagram which shows 1st Embodiment of an embedding information detection apparatus, and is a figure explaining the process which detects data decoding and embedding information. It is a flowchart for demonstrating operation | movement of the embedded information detection apparatus of 1st Embodiment. It is a block diagram which shows 2nd Embodiment of an information embedding apparatus, and is a figure explaining the process which embeds information. It is a flowchart for demonstrating operation | movement of the information embedding apparatus of 2nd Embodiment. It is a block diagram which shows 2nd Embodiment of an embedding information detection apparatus, and is a figure explaining the process which detects data decoding and embedding information. It is a flowchart for demonstrating operation | movement of the embedded information detection apparatus of 2nd Embodiment. It is a figure which shows the convolutional encoder used in Example 1 based on 1st Embodiment. FIG. 3 is a trellis diagram regarding the first embodiment. It is a figure for demonstrating Example 2 based on 1st Embodiment, and is a system block diagram of Example 2. FIG.

  Embodiments of the present invention will be described in detail with reference to the drawings.

(First embodiment of information embedding device)
First, a first embodiment of the present invention will be described. An outline of the digital data information embedding device according to the first embodiment is shown in FIG. An information embedding device 10 according to the first embodiment is a device for embedding information in digital original data that is an information embedding target, and performs error correction encoding processing on the original data and outputs the error correction code. And an information embedding unit 2 that embeds embedded information as an error in the original data that has been error correction encoded by the error correction encoding unit 1. Each of these units can be configured by a dedicated hardware device, or can be realized as a function of one or more processors based on a software program.

  In addition, although the case where a BCH encoding system is used for error correction encoding by the error correction encoding unit 1 is described here, the present invention is not limited to this, and RS (Reed-Solomon) code, Fire code, Goppa code, etc. Algebraic codes, convolutional codes, turbo codes, combination codes, and the like can also be used.

  Hereinafter, a case where a (13,5) BCH code shortened by 2 bits is used for error correction coding of original data by the error correction coding unit 1 will be described. In general, the (n, k) BCH code is a code having an n-bit code length obtained by adding n-k check bits to k-bit data, and has a function of correcting multiple errors.

 In this (13,5) BCH encoding method, double errors can be corrected. First, when the extracted original data is divided into 5 bits and each is BCH-encoded, a BCH code sequence having a code length of 13 bits is generated. As described above, in this BCH code, two errors out of 13 bits can be corrected. Therefore, the embedded information is divided by 2 bits and embedded to create “data with embedded information”. The number of bits into which the embedded information is divided may be set to be equal to or less than the error correction capability of the error correction coding method used.

  The operation of the information embedding device 10 will be described below based on a specific example with reference to the flowchart of FIG. However, in the following specific example, it is assumed that the BCH code is organized (that is, a BCH code in which a check bit sequence is collected).

First, the error correction encoding unit 1 extracts original data to be embedded with information from a predetermined storage medium, and divides the extracted original data by 5 bits (step S1). For example, if the original data is 1011001101,
Original data: 10110 01101 ... Division original data (1)
Is divided into two blocks.

Next, the error correction coding unit 1 performs BCH coding of the original data with a predetermined code length (code length 13 in this embodiment) (step S2). In this example, the error correction encoder 1 performs BCH encoding on each 5 bits of the original data (1),
10 1 1001 1 11010 01 1 0101 0 01101 ... Encoded data (2) (3)
Thus, two encoded data blocks (2) and (3) are generated. Here, each of the encoded data blocks (2) and (3) is obtained by adding 8 check bits to 5 bits of original data. The generated encoded data blocks (2) and (3) are provided to the information embedding unit 2.

Subsequently, the information embedding unit 2 extracts embedded information embedded in the original data from a predetermined storage medium, and divides the embedded information by predetermined bits (2 bits in this example) (step S3). For example, if the embedded information is 1101100101,
Embedding information: 11 01 10 01 01 ... Embedding information (4)
And divided. In the present embodiment, the information embedding unit 2 performs the process in step S3. However, the present invention is not limited to this, and a device that performs the process in step S3 may be provided in front of the information embedding unit 2. .

  Next, the information embedding unit 2 identifies the insertion position for inserting the embedded information into the 13-bit BCH code, that is, the encoded data blocks (2) and (3) (step S4). Here, the insertion position can be an arbitrary position, and two arbitrary positions in 13 bits are set in advance. In this example, a case will be described in which the third and eighth bits of each block of the BCH code are set as the embedded information insertion positions.

  As another embodiment, scrambling can be performed by changing the insertion position of the embedded information with time, but the description thereof is omitted here.

  Subsequently, the information embedding unit 2 performs an embedding process of embedding information by adding an embedding information bit to a predetermined position (third bit and eighth bit) of each block in the 13-bit BCH code (step S5). . The addition here is, for example, exclusive OR.

  In this example, 1 + 1 of the first bit (1) of the first block (2) from the top to the first bit (1) and the first bit "1" of the embedded information (4) are added by exclusive OR. = 0 is calculated, and 0 of the calculated value is embedded in the third bit of the first block (2). Similarly, “1” of the 8th bit of the first block (2) and “1” of the 2nd bit of the embedded information (4) are added by exclusive OR, thereby calculating 1 + 1 = 0. The calculated value 0 is embedded in the eighth bit of the first block (2).

  Further, 1 + 0 = 1 by adding “1” of the third bit of the second block (3), which is the next 13 bits, and “0” of the third bit of the embedded information (4) by exclusive OR. Is calculated, and 1 of the calculated value is embedded in the third bit of the second block (3). Similarly, 0 + 1 = 1 is calculated by adding “0” of the 8th bit of the second block (3) and “1” of the 4th bit of the embedded information (4) by exclusive OR. The calculated value 1 is embedded in the eighth bit of the second block (3).

  In actual processing, since the third and subsequent blocks exist for the BCH code of the original data, the following processing is continued in the information embedding unit 2 until the embedded information (4) cannot be embedded. If the embedding cannot be performed, the process in step S5 is terminated. The data with embedded information that has been processed is filed in a predetermined format by the information embedding unit 2 in step S6, and is appropriately stored in a predetermined storage medium or transmitted to a target device.

By performing the above-described embedding process, the values of the 3, 8, 16, 21,... Bit from the beginning of the BCH code data of the encoded original data are 0, 0, 1, 1, respectively. ... Therefore, the data with embedded information in this example is
1001001011010 0110101101101 ・ ・ ・ Data with embedded information (5)
It becomes.

(First Embodiment of Embedded Information Detection Device)
Next, an embedded information detecting device corresponding to the above-described information embedding device will be described. An outline of the embedded information detecting apparatus according to the first embodiment is shown in FIG. The embedded information detection apparatus 20 according to the first embodiment is an apparatus that detects embedded information from digital data (embedded information-added data) in which embedded information is embedded, and is embedded as an error in the embedded information-added data. A decoder 3 (restoration processing unit) for restoring the embedded information is provided.

  Hereinafter, with reference to the flowchart of FIG. 4, the operation of the embedded information detecting device 20 and the principle of decoding of the data with embedded information will be described based on the specific example described above.

  As described above, when the original data is “1011001101”, it is divided into “10110” and “01101” of 5 bits at step S1 (divided original data (1)), and BCH encoding (8 bits) at step S2. Are added), and two encoded data blocks (2) and (3) of “1011001111010” and “0110101001101” are generated. Then, in step S3, the embedding information is divided into 2 bits and the embedding information (4) of “11 01 10 01 01” is generated. In step S5, embedded information is embedded in predetermined positions (3rd and 8th bits) of each block in the 13-bit BCH code, thereby embedding information is embedded, and data with embedded information (5) As “1001001011010” and “0110101101101” are generated. That is, in the data with embedded information (5), the embedded information is embedded in the third and eighth bits of each block.

  First, the decoder 3 inputs the data (5) with embedded information in step S11, and executes the decoding process of the input data (5) with embedded information in step S12.

  Decoding is to detect and correct errors that can be included in the encoded data using redundant bits (check bits) added to the original data by error correction encoding. Known decoding methods include Euclidean decoding method, Peterson decoding method, Welch-Barrekamp decoding method, Ready Robinson decoding method, Viterbi decoding method, etc. A case where the decoding process is performed by the decoder 3 will be described. When the data (5) with embedded information is processed by the Euclidean decoding method, a predetermined position where the embedded information “1” is embedded in the data (5) is detected as an “error position”.

  In this example, 1 is added to the 3rd and 8th bits of the first block and the 8th bit of the 2nd block. Therefore, the 3rd and 8th bits of this 1st block and the 8th bit of the 2nd block are added. The bit is detected and output as an error position (step S13). The third bit of the second block is not detected as an error position because the embedded information “0” is added.

  At this time, the decoder 3 performs embedding information restoration processing by associating 1 with a predetermined position where an error is detected and 0 with a predetermined position where the error is not detected (step S14). By such restoration processing, the embedded information in this example is estimated as “1101...”. In step S15, the decoder 3 performs error correction coding by adding the estimated value to the third bit and the eighth bit (by exclusive OR) of each block of the embedded data-added data (5). Restore the original data.

Specifically, in the process of step S15, as the original data encoded with BCH,
1001001011010 + 0010000100000 = 1011001111010 ... Encoded data (2)
0110101101101 + 0000000100000 = 0110101001101 ... Encoded data (3)
Is restored.

  In subsequent step S16, the decoder 3 extracts predetermined bits (5 bits in this example) from the head of the encoded data (encoded data block) (2) and (3) restored in step S15, and in the order of extraction. The original data is extracted and restored by arranging them.

Specifically, in the process of step S16, “10110” is extracted from the encoded data (2), and “01101” is extracted from the encoded data (2).
10110 01101 ... Original data (1)
Thus, the original data is completely restored.

  Note that “data error” means that 1 is added to the correct bit of data, and when a decoding method such as the Euclidean decoding method is used in this way, an error location of the data is output.

(Second Embodiment of Information Embedding Device)
Next, a second embodiment of the present invention will be described. FIG. 5 shows an outline of an information embedding device for digital data according to the second embodiment. The information embedding device 10A according to the second embodiment is a device for embedding information in digital original data that is an information embedding target. The information embedding device 10A performs error correction coding processing on the original data and outputs the first data. An error correction coding unit 1; a second error correction coding unit 11 that performs error correction coding processing on embedded information and outputs the result; and an error correction coded embedded data that is error correction coded And an information embedding unit 2 that embeds information as an error. That is, in the second embodiment, the error correction code is also applied to the embedded information. Each of these units can be configured by a dedicated hardware device, or can be realized as a function of one or more processors based on a software program.

  In the following, a case where the BCH encoding method is used in both the first error correction encoding unit 1 and the second error correction encoding unit 11 will be described. However, the present invention is not limited to this, and correction is performed by BCH encoding. High-performance convolutional codes and RS (Reed-Solomon) codes can also be used.

  Hereinafter, a case where the (13, 5) BCH code is also used for error correction coding of embedded information by the second error correction coding unit 11 will be described with reference to the flowchart of FIG. Since the processing of the original data by the first error correction encoding unit 1 is the same as in the case of the first embodiment described above, the same example is used, and the same step number is used for the same processing in the flowchart. The description is omitted as appropriate.

  Steps S1 and S2 are processes performed by the first error correction coding unit 1, and are the same as steps S1 and S2 described above in the first embodiment.

On the other hand, the second error correction encoding unit 11 extracts embedded information data from a predetermined storage medium, and divides the extracted data into 5 bits (step S31). For example, if the embedded information is 1011011010,
Embedding information: 10110 11010 ・ ・ ・ Embedding information data (6)
Are divided into two blocks.

Next, the second error correction encoder 11 performs BCH encoding of the embedded information data with a predetermined code length (13 in this example) (step S32). In this example, by encoding each 5 bits of the embedded information data (6) with BCH,
1011000011011 1101011010110 ・ ・ ・ Encoding embedded information (7)
A BCH code consisting of two encoded blocks is generated. Here, each encoded data block is obtained by adding 8-bit check bits to 5-bit embedded information.

Subsequently, the second error correction encoding unit 11 divides the generated encoded embedding information (7) into predetermined bits (2 bits in this example) (step S33). In this example, by the process of step S33,
10 11 00 00 11 01 11 10 10 11 01 01 10 ・ ・ ・ Embedding information (8)
Is generated. The generated embedded information (8) is provided to the information embedding unit 2.

  Next, the information embedding unit 2 performs a predetermined position (third and eighth bits) of each block of the 13-bit BCH code of the original data, that is, the encoded data block (2) (3) 1011001111010 0110101001101. Is identified (step S4), and an embedding information bit is added to the position (step S5), and embedding processing of embedding information is performed in the same manner as in the first embodiment.

By such embedding process,
As 1 + 1 = 0, 1 + 0 = 1, 1 + 1 = 0, 0 + 1 = 1,...
1001001111010 0100101101101 ・ ・ Data with embedded information (8)
Is generated. The generated data (8) with embedded information is filed in a predetermined format by the information embedding unit 2 in step S6, and is appropriately stored in a storage medium or transmitted to a target device.

  In the second embodiment, by encoding “embedding information” in advance as described above, three or more errors (that is, error correction of the BCH-encoded original data) are added to the encoded embedded information-added information (9). Even when the capability includes two errors and the number of errors exceeds this, the possibility of correct decoding into the encoded embedded information (7) increases by using the error correction capability of the embedded information.

(Second Embodiment of Embedded Information Detection Device)
Next, an embedded information detection apparatus corresponding to the information embedding apparatus 10A of the second embodiment described above will be described. An outline of the embedded information detecting apparatus of the second embodiment is shown in FIG. The embedded information detection apparatus 20A according to the second embodiment is an apparatus that detects embedded information from digital data in which encoded embedded information, which is encoded embedded information, is embedded as an error. And the first decoder 3 (first restoration processing unit) for restoring the encoded embedded information embedded as an error, and the encoded embedded information restored by the first restoration processing unit 3 And a second decoder 31 (second restoration processing unit) that performs correction to restore the embedded information.

  Hereinafter, with reference to the flowchart of FIG. 8, the operation of the embedded information detection apparatus 20A and the principle of decoding of the data with the encoded embedded information will be described based on the specific example described above. That is, in this example, “1001001111010”, “0100101101101”,... Is generated as data (9) with embedded information in which the encoded embedded information (7) is embedded.

  First, the first decoder 3 inputs the data with embedded information (9) in step S11, and executes the decoding process of the input data with embedded information (9) in step S12. Note that the processes in steps S11 to S13 are the same as those in the first embodiment.

  When data with encoded embedded information (9) “1001001111010 0100101101101...” Is processed by the Euclidean decoding method (step S12), the third bit of the first block in which 1 is embedded, the third bit and the second bit of the second block The eye is detected as an error (error position) (step S13), and the bit embedded at that position is 1. When no error is detected at a predetermined position of embedding, the bit embedded at that position is zero. By such processing, the embedded information is estimated as a bit series 1011... (Step S21).

  However, there are cases where the data with encoded embedded information (9) includes three or more errors (that is, errors exceeding the error correction capability of the original BCH encoded data). In this case, decoding is not performed correctly and the encoded embedded information (7) is not obtained.

  Therefore, when Euclidean decoding is performed on the bit sequence of the embedded information extracted from the predetermined embedding position, if there are 2 errors or less per 13 extracted bits, it can be corrected. For this reason, Euclidean decoding is always performed on a bit sequence obtained from a predetermined embedded position. Therefore, if there are two or less errors, they are completely corrected, and at this time, the encoded embedded information (7) is extracted from the first decoder 3 (step S21). Further, the extracted encoded embedded information (7) is Euclidean decoded by the second decoder 31 (step S22), a bit error position is detected (step S23), and a predetermined bit is associated with the detected bit error position. As a result, “10110 11010...” As the embedded information (6) is obtained (step S24). Thereafter, the original data is completely restored in the same manner as in the first embodiment (step S25).

  The greatest feature of the present invention is that other information can be embedded in the original data without any change. This is clear from the embedding / extraction method of the present invention. In the conventional method, since a part of the original data is replaced with the embedded data, the original data is changed as a result. If the target is a large amount of data such as an image, even if there is some data loss, the appearance will not be affected. However, the conventional embedding method cannot be used for an object with a small amount of data such as text data or an object that is required to be complete data. This problem is solved by using the method of the present invention.

(Example)
Examples of the present invention will be described below. However, the present invention is not limited to this embodiment.

Example 1
The inventor of the present application conducted a first experiment according to the first embodiment. In this experiment, image data was used as original data, and music data was used as embedded information. Further, a convolutional code was used as the error correction code. FIG. 9 is a diagram showing a convolutional encoder used for error correction coding of a bit sequence {it} of image data, and FIG. 10 is a Retris diagram used for decoding. In FIG. 9, M1 and M2 are delay elements, and the code block length is 14. With respect to the convolutional encoder, the coding rate can be increased to 2/3 by punctured coding in a communication channel with little noise. If the convolutional code generated by this encoder is used, two errors per code block can be corrected.

The relationship between the input and output of the encoder of FIG.
_{W 1t = i t + i t} -1 + i t-2
_{W 2t = i t + i t} -2
Given in. However, the symbol + is an exclusive OR.

  In this experiment, first, RGB component data is acquired from image data, and a bit block of each component is divided into 7 bits and then convolutionally encoded to obtain a code block sequence. Next, the music data is embedded in the obtained code block sequence. That is, the music data is divided into two bits, and the first bit and the fifth bit are selected as the two predetermined positions between the first bit and the tenth bit of the code block as the embedding position of each 2 bits. . Note that if an embedding position is selected from the 11th bit to the 14th bit, a decoding error is likely to occur. The embedded information could be obtained by comparing “data with embedded information” before decoding with a decoded sequence obtained by Viterbi decoding.

  As a result of such an experiment, when the convolutional encoder of FIG. 9 is used to perform error correction coding on a 3.5 MB bitmap image (original data) and embed 160 Kbps music data in it, about 51 seconds of music data can be embedded. did it. At this time, the “data with embedded information” has a file size of about 7 MB. The amount of information that can be embedded is proportional to the size of the image data and inversely proportional to the bit rate of the music data to be embedded. Next, when Viterbi decoding is performed using the trellis diagram of FIG. 10 to extract bitmap image data and embedded music data, both the original data (image) and the embedded information (music) are lost. It was possible to reproduce without.

(Example 2)
The inventor of the present application conducted a second experiment according to the first embodiment. In this experiment, image data was used for original data, and image data was also used for embedding information. As shown in FIG. 11, in this experiment, a convolutional encoder is used as the error correction encoding unit 1, a Viterbi decoder is used as the decoder 3 (restoration processing unit), and the output of the information embedding unit 2 The data was transmitted to the Viterbi decoder via the communication path. A convolutional encoder that performs convolutional code with a constraint length of 5 and a coding rate of 1/2 was used. The sizes of the original image and the embedded image were 320 × 240 pixels and 160 × 120 pixels, respectively. In addition, additive white Gaussian noise was implemented as an error (noise) in the communication channel.

  As a result of this experiment, it was confirmed that the embedded information amount of up to 25% of the information amount of the original data can be transmitted in a secret manner on the communication path of BER = 0.042. From these results, it became clear that steganography with high confidentiality and a large amount of information can be easily made.

(Application example of the present invention)
-Application to steganography In conventional steganography, secret information is directly embedded in cover data by using the property of information embedding objects (cover data) such as images as original data. In contrast, in the present invention, first, cover data such as images and sounds, which are transmission media for secret information, is error-correction-encoded, and then secret information such as images and sounds to be embedded is set as “error” in the encoded data. Insert and create a stego object. When decoding the stego object, the secret information inserted by the error correction function of the error correction code is extracted as “error”. According to the present invention, even if the stego object is restored, only the cover data is restored, and the secret information is not sensed at all.

-Application to mobile phones and terrestrial digital broadcasting equipment Since mobile phones and terrestrial digital broadcasting equipment encode data using convolutional codes, it is easy to incorporate the present invention into such equipment, Therefore, it is possible to embed information continuously.

-Application to images of digital cameras and mobile phones For example, about 400 Kbytes of information can be embedded in an 800 × 600 pixel image of a mobile phone.

・ Application to QR code
Confidential information can be embedded in the data code part of the QR code.

-Application to medical images Information such as personal information and heart sounds can be embedded in medical images such as X-rays.

・ Applications to mobile phones at the time of disasters Mobile phones at the time of disasters are likely to be disconnected, and substitutes such as data communication are considered as countermeasures. If the present invention is used, an image with sound can be easily created, so that the line usage rate at the time of a disaster can be lowered when used instead of conversation.

10, 10A Information embedding device 1, 11 Error correction coding unit 2 Information embedding unit 20, 20A Embedded information detection device 3, 31 Decoder

Claims (10)

A device for embedding information in digital original data to be embedded,
An error correction encoding unit for performing error correction encoding processing on the original data;
An information embedding unit that embeds embedding information as an error in the error correction encoded original data;
An information embedding device for digital data, comprising: The information embedding unit is subjected to the error correction coding by any one of BCH coding, Reed-Solomon coding, Fire coding, Gopper coding, convolutional coding, turbo coding, or combination coding. 2. The digital data information embedding apparatus according to claim 1, wherein said embedding information is embedded in original data. The error correction encoding unit divides the original data into predetermined k bits, adds a check bit having a predetermined length to the divided bits, and generates an n-bit code.
The information embedding unit divides the embedded information for each predetermined bit, calculates a value of a corresponding bit with respect to a predetermined value of a predetermined bit of the divided bit, and calculates the calculated value. 2. The information embedding apparatus for digital data according to claim 1, wherein embedding information is embedded by replacing the divided bits with a predetermined value of a predetermined bit. A second error correction encoding unit that is arranged in a preceding stage of the information embedding unit and outputs the embedded information by performing an error correction encoding process;
3. The information embedding apparatus for digital data according to claim 1, wherein the information embedding unit embeds embedded information, which has been error correction encoded, into the error correction encoded original data as an error. An apparatus for detecting the embedded information from data with embedded information in which embedded information is embedded in digital original data,
An embedded information detecting apparatus for digital data, comprising: a restoration processing unit for restoring embedded information embedded as an error in the data with embedded information. The restoration processing unit performs a decoding process on the data with embedded information, identifies a predetermined bit of the decoded data with embedded information, detects a bit error position, and detects the detected bit error position. 6. The digital data embedding information detecting apparatus according to claim 5, wherein the embedding information is restored in correspondence with predetermined bits. 7. The embedded information detection of digital data according to claim 6, wherein the restoration processing unit calculates the restored embedded information to a predetermined bit of the data with embedded information and restores the original data. apparatus. The restoration processing unit restores the encoded embedded information embedded as an error with respect to the data with embedded information,
6. The digital data embedding information detection apparatus according to claim 5, further comprising a second restoration processing unit that performs error correction on the restored encoded embedding information to restore the embedding information. A program for embedding information in original digital data to be embedded,
Processing to perform error correction coding on the original data;
A process of embedding embedded information as an error in the error correction encoded original data;
A program that causes a computer to execute. A program for detecting the embedded information from data with embedded information in which embedded information is embedded in digital original data,
A program for causing a computer to execute restoration processing for restoring embedded information embedded as an error in the data with embedded information.

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