TW455782B - Embedded information detection method and system - Google Patents

Abstract

To provide a method and a system by which additional electronically embedded information can be safely detected in many and unspecified places. A server reads data in which additional information is embedded, and requests that a tamper resistant device, on which is stored a secret key, perform the detection of the additional information. At this time, the server reads mask patterns from mask data, calculates inner products for the mask patterns and the data in which the additional information is embedded, and transmits the inner products to the tamper resistant device. In order to detect the additional information, the tamper resistant device adds the inner products received from the server, and uses the secret key to determine a threshold value. To determine a threshold value, a mask pattern used for detection is created by using a secret key that is internally stored in the tamper resistant device. The inner product of the data received from the server and the mask pattern is calculated to determine whether information has been embedded.

Description

4 5 5 7 8 2 V. Description of the invention (1) Background of the invention: The present invention relates to a system for detecting additional information embedded in data electronically. More specifically, the present invention relates to a system using an intelligent chip card and a computer (such as a server) to securely and efficiently detect additional information as an electronic watermark in embedded data (such as image data). And method, and the present invention relates to a storage medium storing a program for the system and method. BACKGROUND: In order to popularize electronic watermark technology and to make it widely used by general users, first of all, it is necessary to securely detect additional information embedded electronically (watermark in many non-specific places) ) Device. However, because the traditional traditional electronic watermarking technology uses a # key system, and according to the symmetric key system, the same key is used for information ingestion and detection, so it may be placed in the place where additional information is executed. One of the places where the device was detected stole the parent secret key that was used to embed additional information. Therefore, there is currently a great need for a method and system that completely prevent tampering (change prevention) of the secret key while ensuring that the detection of additional information is performed efficiently. One of the most existing devices that can prevent tampering is the smart chip card. The smart chip card is a smart card containing an internal CPU and a memory. The information stored on the smart chip card is protected by a password, which can prevent illegal reading and rewriting of the information (the smart chip card is tamper-resistant). As a result, users can use smart chip cards to securely store private data. Therefore, in general, for security and portability, the user's information such as credit card numbers and secret keys

455 78 2 V. Description of the invention (2) The personal information is stored in the size and shape of the smart chip, and the amount of smart chip is limited, so a method and system that can compensate for the capacity of the smart body with additional information are needed. Problems to be solved by the present invention: Card. However, because the computing speed and memory capacity available to smart chip cards can ensure the limited and secure detection of chip cards' limited processing power and memory factors, it is an object of the present invention to provide a method that can Method and system for safely detecting additional information embedded electronicallyZero

Cj Another object of the present invention is to provide a method and system that can cooperate with a tamper-resistant device and a server when detecting additional information. Yet another object of the present invention is to provide a method and system that can safely and efficiently perform detection of additional information while compensating for limited processing power and memory capacity available to prevent tampering devices. Yet another object of the present invention is to provide a method and system for safely and efficiently detecting additional information. According to the method and system, a tamper-resistant device needs to perform calculations with high security, and a server performs all other operations. Calculation. Yet another object of the present invention is to provide a method and system for detecting additional information safely and efficiently. According to the method and system, a tamper-proof device performs at least those calculations required to extract additional information, and a server calculation exceeds The required redundant inner product (redundan t inner product) in order to maintain safety D Summary of the invention:

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4 δ STB 2 V. Description of the invention (3) In order to achieve the above-mentioned items, a temple server first reads the information of the additional information and requires that one of the secret keys is stored to prevent the tampering device from performing additional information detection. At this time, the server reads the mask pattern from the mask data, then calculates the inner product of the mask pattern and the data embedded with additional information, and transmits the inner product to the tamper-resistant device. In order to detect additional information, the tamper-resistant device adds the inner product received from the server and uses the secret gold loss to determine a critical value. In this configuration, the work that calculates the inner product can be assigned to a server that can perform high-speed calculations, while the work that requires a high degree of security, which only adds the inner product and determines a critical value, is assigned to a prevention Tampering with the device. That is, in order to maintain operational safety, the tamper-resistant device will be responsible for performing the minimum inner product calculation required to extract additional information (a message), and the server will be responsible for performing the more redundant inner product calculation required. Accordingly, a method and system can be provided that can safely perform detection of additional information embedded electronically in many non-specific locations. FIG. 1 is a conceptual diagram of the present invention. In a secure environment, a secret key is used to embed additional information (a message) in the data (110) (in this example, image data), and then an Internet service provider (120) This information is transmitted to the general user (an unsafe environment). A server (130) then performs only those data calculations that do not require a secret gold record. 'Then, in order to detect the embedded information, a tamper-prevention device (in this example, a smart chip card reader (150) in this example) inserted into a tamper-proof device reader (in this example) is required. Perform the calculations needed for a smart chip card (1 40)) using a secret key.

4557B 2 V. Description of the invention (4) Preferred embodiment f Before starting to describe the preferred embodiment of the present invention, the basic technology of the present invention will be explained ("wat⑽rking"). Electronic type two electronic seals (== 3⑽1 348426. The two step ΐΐΓ image content data contains NxN pixels. When the mask to be executed = pixel block size is kxk, the image data contains 1§

Blocks. The image data block is defined as J, and k x k elements (m e 丨 -1 ο 1 I >) ϋ 4 are prepared. a-^ ^ ^ ^ ^ 1 Each mask pattern composed of mu. In the ^ condition, the sum of all elements is 0, and each mask pattern is a positive parent to each other, which means that the inner product of any two patterns is ^. They are also opposite patterns, where the individual elements of the resulting pattern are multiplied to form these patterns with opposite symbols. A total of eight patterns are provided ’MP (P = 0, 1, _.., Ή, including patterns with opposite signs, which form the following illustrated 4 × 4 patterns. —Eight [Formula 1]

It performs the message embedding operation described below. A sequence of each 0 in the bit sequence of _

O: \ 60 \ 60001.PTD Page 9 455782 V. Description of the invention (5) ί-ι, i} (i = o, l ,. · κ. When providing a source of /, 1). The total length of the sequence is defined as when the random number generator obtains a result r i, the following equation will be obtained. I i, = 1 i + Mp 氺 βj, where P = ri mod K and j = ri mod J. In order to detect a message at bit position Q, a sequence of random numbers is generated using the same source as the embedding and the sum of the inner products of I i and M p, in the manner described below. Calculate ri mod J = q.

Sq = Z (Ii ,, Mp) >

Where p = r i mod K if Sq, then Bq = 1, and if Sq is -T, then Bq = 〇. For example, ^ " ^ < Sq < T ', you can be sure that no information is embedded. Clause: As a basic technology piece associated with the present invention, for this embedding, it is important to determine the outside that has been enemies, because it uses the ^ mask mode and a correspondence in the message. Bit. Blocks, so vertical: 2 mask mode embeds -bit information into the complex & / makes a block similar to a specific mask pattern 彳 | # 3 Q blocks, also can not + 士 隹

Consider information under security. f In the present invention, despite the corresponding relationship, 1) the inner product of each mask weight and each block position, the device is responsible for calculating data and each mask model. At this time, in order to prevent the smart chip card from performing the corresponding relationship, the server must calculate the total leakage of information related to the corresponding relationship. 2. Explanation of the invention (6) Unnecessary) Product within each mask mode. Fig. 2 is a schematic configuration diagram of a system of the present invention. As shown in Figure 2, the server calculates the inner product of the image data and the mask pattern read from the mask data, and transmits the inner product to a smart chip card in the form of a tamper-resistant device. The smart chip card uses its internally stored secret key to perform distribution and addition on these inner products, and decides a threshold value for detecting additional embedded information (for extracting a message). The calculations performed by the server will now be detailed. A new set of mask patterns are linearly combined with each mask pattern used for embedding and provided to the server. When the set of mask patterns used for embedding is {Μα, Μ " ... Μ,. ,, -Μ0, -Μ "·., -Μκμ}, it is assumed that the patterns with opposite signs are the same This is because only the inner product is negative, and these new patterns are formed by the linear transformation of K-dimensional vectors. More specifically, when [Me,... Μκ -1] is a K When there are two-dimensional row vectors and P is a K-dimensional regular matrix, [M ′., M ′ ”....., M ′] τ = P [Μ〇) …… Μκ _]] τ. For example, when using the following formula [Formula 2] '1 0 0 0' 0 0 11 0 0 1-1

When L J transforms the mask mode Μρ, the result {Μ ′ D, Ψ ........ Μ ′ 3} is as follows:

Page 11 4 5 5 78 2 V. Description of the invention (7) [Formula 3] '1 -1 -1 1' 1 t -1 -1 '' 1-1-11 '' -1 -1 1 1 '1 1-1-1 -1111 -1-11 1 -11 1-1 -11 1-1 -1-11 1 > -1-11 1 1-1-1 1? -11 1-1 1 1 -1 -1 _ 7 1 1-1-1 1-1-11. The server calculates the result {M'c, M '........ M'h} and the product within an image. First, the inner product of M > and an image block is calculated for the entire image, and the inner product is transmitted to the smart chip card, and the procedure is repeated for different mask modes. That is, the following data sequence is transmitted to the smart chip card. [Formula 4] DS = {(Μ′0, Ι0), (M, Q, B), ·, (Μ ′., I [w), (Μ ′ ^ TG), (『丨, ij, ..., (M ,, ... (M,], iiS— Figure 4 is a flowchart of the calculation performed by the server. First, the initial values of the internal variables i and j are set to 0 □. Then in step (410), The mask data Mk 'reads the mask mode Mi'. In step (420), the image block I j is read from the image data, and in step (430), the product between Mi 'and I j is calculated, and The inner product is transmitted to the smart chip card inserted into the smart chip card reader. In step (440), the variable j is incremented and a check is performed to determine whether all image blocks have been processed. When processing After all the image blocks are obtained, the variable i is incremented in step (450), and a check is performed to determine whether all mask modes have been adopted. If all mask modes have been adopted, then this procedure is terminated Process.

Page 12 45 578 2 V. Description of the invention ¢ 8) The calculation will now be detailed. FIG. 3 is a conceptual diagram of operations performed by the smart crystal moon card of the known tamper-proof device shown in FIG. 3 using the _: chip card. Such as a random number source) to store a secret key (corresponding to the incoming data sequence in this example, and a random number and distribution uses the random number to lose the content. When the obtained data sequences are added as When bit sequence memory is embedded with extra information (a message), when the Kyrgyzstan exceeds a critical value, it is determined that a recovery amount key has been generated ^ = such data. More specifically, using a secret device and a mask When transforming and storing the restoration function in the tamper-prevention function, the result of the replacement of the data received from the feeder is equal to the information entered in the mask. Provide (for example, image data ~ embedded in additional information (messages) is used in smart chips ;: product. DS = {ds0i0) ds T 'distribution—sequentially transmitted data series are weighted and added to ° ^ for supply, dsH, iS-d (L = K * IS), and the memory array of the memory array = (", · .., and for cloth, it uses ^ 4 for the message bit length J. For the extension number q (random number and I j The information memory mj is 1S) 'and the random number must be selected to use Mw, η_J. For (weighted,' Although ', but Q = n mod K) to detect the embedding As for the mask mode, Dongdou & Swap matrix P performs the transformation of the mode used for detection. The inverse matrix of the mask mode transformation matrix P is obtained ~ = 丨 ~ 丨) Therefore, for ^ Task, i, add dSk.Jp # . For example, p_i is given by

ο: \ 6〇 \ 6〇ωι.ρτο Page 13 55 78 2 V. Description of the invention (9). [Formula 5] Corpse ο 121 1 2 ο ο 112 112 121--2 ο ο 1-21-2 ο ο Therefore, 1 / 2M 'G + 1 / 2M' [can be used to detect the information embedded using the pattern M0 . When pattern i is used to embed the i-th data in the image block, the value obtained by multiplying the i-th data sequence dsQ, 丨 by 1/2 is added to the data sequence dsQ, 丨, and the IS data sequences dsh; the value obtained by multiplying by 1/2 is added to the data sequence dsi}. Fig. 5 is a flowchart of calculations performed by the tamper-resistant device (smart chip card) of the present invention. First, in step (5 1 0), the initial value of the internal variable k is set to 0, and in step (520), it is read as the source of the random number of a secret key, which is applied as the internal variable i ( = 0) values of 1 ^ random numbers. In step (530), a sequence of inner product data is read from an external interface such as a serial port of a server. In step (5 40), an index j of the message memory is calculated, and in step (5 50), an index q of a mask pattern for detection is calculated. In step (560), Pqk is extracted from the mask pattern transformation matrix P-1, and a weighting calculation is performed for the detection pattern. In step (570), the message memory is updated, and the internal variable i is incremented in step (580) to determine whether the process has been completed. If the process is not completed, the control of the program returns to step (530). If the process has been completed, it is passed in step (5 9 0)

G: \ 60 \ 60001.PTD Page U 4 5 578 2 V. Description of the invention (10) Increase the internal variable k 'to determine whether the process has been completed. If the process has not been completed, program control returns to step (520). If the process has been completed, then the extraction of additional information (a message) is terminated while maintaining the contents of the message memory. When detecting and extracting additional information (a message), if the critical value T is compared, and it is found that | min (mj ′) | 2T ′, it is determined that a message has been embedded. In this case, for the individual message memory m j, suppose: if m j g 0, then B j = 1, and if m] _ < 0, then B j = 〇,

And form a series of message bits. Fig. 7 shows a general hardware configuration of a feeder according to the present invention. A system (100) includes a central processing unit (CPIJ) (1) and a memory (4) β a bus (2) and an IDE controller (25) connecting the CPU (1) and the memory (4) To a hard disk drive (13) (or a storage media drive such as -M0, an optical disc drive (26), or a DVD (32), etc.) as an auxiliary storage device. Similarly, the bus (2) and an SC SI controller (27) connect the CPU (1) and the memory (4) to a hard disk drive (30) (or such as a MO (28), an optical disc drive (29), or a storage media drive such as a DVD (31)

Actuator). A floppy disk drive (20) is connected to the bus (2) via a floppy disk drive controller (19). A floppy disk is inserted into the floppy disk drive (20), and can interact with an operating system and send instructions to the CPU (1) to store the code or data of a computer program implementing the present invention on the floppy disk, or Stored in hard drive (3) (or ㈣, optical drive (26), or DVD (32)), and stored in-ROM (14). The computer

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4 5 5 78 2 V. Description of the invention (u) 3 ί f t S 忆 忆 体 (4) ′ and execute the computer program. It is best to store the mask data for the hard drive ⑴). Can be: type or divide the code of the computer program into multiple; slaves for storage in multiple storage media. Good dagger) $ 'contains: user interface hardware components such as pointing devices (mouse or joystick) _ _ net to input data; and two display devices (1 2) to provide image data to use This can be displayed on the display device (12)-preventing tampering with the results obtained when detecting additional embedded information. In addition, a printer can be connected to the system (100) via a parallel port (6), or a modem can be connected to the system (100) via a serial port (15). In order to communicate with another computer, the system (100) can be connected via a serial port (15) and a modem or through a communication interface card (18) (such as an Ethernet or a sign ring network interface card). ) And connected to a network. A remote transceiver can be connected to the serial port (15) or parallel port (16) to exchange data with the system (100) using infrared or cables. As shown in FIG. 8, a tamper-resistant reader (8 1 0) can be connected to the serial (15) or communication interface card (18) of the system (1 QQ) in order to communicate with a chip such as a smart phone. One of the cards prevents tampering devices from exchanging data. Although the tamper-resistant device reader (810) is externally connected in FIG. 8, a modification in which the tamper-resistant device reader is provided in the system (100) can be adopted without departing from the scope of the present invention. the way. One (8) in the system (100) is used to receive audio generated by a digital / analog (d / A) conversion performed by an audio controller (2 1) through an amplifier (2 2). Signal 'and output the signal as sound. Audio controller (21) implementation

Page 16 4 5 5 78 2 V. Description of the invention (12) Analog / digital (A / D) conversion of audio information received via microphone (24) to import external audio data into the system (100). As mentioned above, we should be easy to understand and provide the feeding device of the present invention with the following components: a general personal electrical version * (pc), a workstation, a notebook-type personal computer, a palm-top type; a computer or a A network computer, or a television or other home appliances with a computer; a video game machine with a communication function; a communication terminal with a communication function, such as a telephone, a fax machine, a portable Phone, = PHS or a PDA; or a combination of the above components. However, these components are only examples, not

All of these components are necessary for the present invention. Figure e is a comparison table of the memory required when only one personal computer detects additional information and when a smart chip card and a server cooperate to detect additional information. In FIG. 6, the size of the image data (the size of the image) is 5 12 and 512 (above) and 1 024X 1 024 (below). In order to ensure the safety of operation1, the smart chip card performs the minimum inner product calculation required to extract additional information (aiL heart), and the server performs the required inner multiplication product calculation. Advantages of the invention *

The tamper-prevention device and feeder according to the present invention can cooperate to detect additional information safely and efficiently. Thanks to the detection system of the present invention, electronically embedded additional information can be safely detected in many non-specific locations. U Brief description of the drawings: Fig. 1 is a conceptual diagram of the present invention. Fig. 2 is a schematic slave diagram of a system according to the present invention. Figure 3 is a summary of the operations performed by a tamper-resistant device (smart chip card)

4 5 578 2 V. Description of the invention (13) Read the picture. Figure 4 is a flowchart of the calculations performed by the server. Fig. 5 is a flowchart of calculations performed by the tamper-resistant device (smart chip card) of the present invention. Figure 6 is a comparison table of the memory required for detecting additional information. FIG. 7 shows an exemplary hardware configuration of a server used in the present invention. Fig. 8 is a conceptual diagram of a server connected to a reader of a tamper-resistant device.

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Claims (1)

4 5 5 78 2 Case No. 88114190 h '% 〇 Amendment VI. Patent application scope 1 A system that uses tamper-proof device and a server to detect additional information of embedded capital, including: (1) as the servo A reading device of a component of the server for reading data embedded with additional information; (2) a requesting device of the server for requesting the tamper-resistant device connected to the server to detect the additional embedded information; and (3) A device that uses a secret gold deposit held in the tamper-resistant device as a component of the tamper-resistant device to detect the additional embedded information. For example, the application of the system cover of the application server is connected to the application system of the application system, and the application of the system to the gold application of the application system is required. Please refer to the application form of the application form. The information of the model shall cover the equipment of 3. The equipment of the equipment 4. The secret of the equipment 5. The scope of the equipment shall be detected in item 1 of the additional information embedded in the data, which requires the detection of the additional embedded information. The device (2) is a component, and the server reads each mask pattern, calculates the inner product of the data embedded in the additional information, and sends it to the tamper-resistant device. The additional item of the detection of item 1 is embedded in the additional data in a tamper-prevention device reader using the tamper-prevention server. The detection (2) of the profit range is based on the additional information embedded in the data. The device (3) that detects the additional embedded information uses the distribution and addition of the inner products received by the server. The detection of item 2 of the scope of interest is additional information embedded in the data. The data is image data, and the inner product of the data and the image product is the inner product of the image data and the mask mode. O: \ 60 \ 60001.ptc Page 19 2001.07.19. 020 4 5 5 78 2 _ Case No. 88114190 Xi Gongnian, Xi Yue > " 〇 日 ___ 六 、 Scope of patent application 6. Such as the scope of patent application The system for detecting additional information embedded in the data of item 2, wherein the calculation of the inner product of the masking mode and the data embedded in the additional information includes a redundant inner space which is not required to detect the embedded information. Calculation of the product. 7. The system for detecting additional information embedded in data such as the scope of patent application, wherein the tamper-resistant device is a smart chip card, and wherein the tamper-resistant device reader is a smart chip card reader machine. 8. A tamper-resistant device that detects additional information embedded in a data sequence, including: (1) a device that reads a secret key stored in the tamper-resistant device; (2) reads the data sequence externally A device; and (3) a device that uses the secret record to extract the additional information embedded in the data sequence. 9. A server requesting a tamper-resistant device to detect additional information embedded in data, comprising: (1) a device that reads a mask pattern; (2) a device that reads data embedded in additional information; and (3) a calculation The inner products of the data and the mask patterns are transmitted to the tamper-resistant device. 1 0. A method for detecting additional information embedded in a data sequence by using a tamper-resistant device, including the following steps: (1) reading a secret key stored in the tamper-resistant device; (2) externally Read the data sequence; and O: \ 60 \ 60001.ptc Page 20 2001.07.19.021 4 5 5 78 2 Amendment _ Case No. 88114190 VI. Patent Application Scope (3) Use the secret key to extract the additional information embedded in the data sequence. 1 1. A method for requesting a tamper-prevention device to detect additional information embedded in data using a server, including the following steps: (1) reading each mask mode; (2) reading data embedded in additional information; and (3) Calculate the inner product of the data and the mask patterns, and transmit the inner product to the tamper-resistant device. 1 2. —A storage medium that stores a program that allows a server to request a tamper-resistant device to detect additional information embedded in the data. The program contains: (1) functions that read each mask mode; (2) a function that reads data embedded with additional information; and (3) a function that calculates the inner product of the data and the mask patterns and transmits the inner product to the tamper-resistant device. O: \ 60 \ 6000I.ptc Page 21 2001.07.19.022