49results about How to "Good resistance to attack" patented technology

The invention discloses a combined image compression/encryption method based on compressed sensing, which comprises the following steps of: firstly, a dictionary is formed by combining sub dictionaries obtained by classifying and training by combining a K-SVD method; secondly, an improved orthogonal matching pursuit algorithm is adopted in sparse coding; and finally, encryption is embedded in a compression process so that an encryption/compression algorithm of an image is realized. According to the invention, encryption and compression are tightly linked, therefore, on the premise of no basic influence to rate distortion performance, the attack resistance property and the stability of a system are further improved, the rate distortion performance of static image compression is superior to that of international main trend algorithms such as JEFG2000 and SPIHT at present, the image encryption performance is increased, and common attacks such as cipher text-only attack, chosen-ciphertext attack, known-plaintext attack and chosen-plaintext attack can be resisted. The invention can be used in image storage and transmission in the information security transmission fields such as internet, mobile telephones and video conferences.

The invention discloses a wavelet transform and Arnold based adaptive gray-scale watermark embedded method which comprises the following steps: carrying out square matrix conversion and scrambling processing on an original watermark image; carrying out wavelet transform (three times) on an original host audio to obtain wavelet low frequency coefficients as the embedded pre-selected position of a watermark; automatically searching an optimal embedded sequence from the low frequency coefficients, wherein the optimal embedded sequence is the optimal embedded position of the watermark; and carrying out convolution on a digital watermark image sequence and the optimal embedded sequence, namely, embedding the digital watermark image into the low frequency coefficients of audios. The method is characterized in that in the process of digital watermark extraction, the audios containing watermarks are detected according to the original audio, and a watermark image sequence is extracted from the audios; and in the process of digital watermark reduction, the length and width of the original image are taken as extraction keys, and the extracted watermarks are reduced through the utilization of reverse Arnold conversion and image reconstruction. The method disclosed by the invention is strong in function, quick in computing speed, easy and convenient to implement, and has certain practical values in the aspects of digital image copyright protection and information hiding.

The invention discloses a novel ultra-lightweight QTL (Quasi-Transmission Line) block cipher implementation method. According to the method, a novel generalized Feistel network structure is designed; the structural algorithm overcomes the defect that only a half of grouped data is changed during one-round iterative operation of the conventional Feistel network structure, and realizes that all grouped data is changed by the one-round iterative operation. F functions in the round operation of the algorithm comprise an F1 function and an F2 function; S1 and S2 boxes are adopted respectively; the conversion process of the F functions comprises round key add, S box substitution, P replacement and S box substitution; different S box and P replacement only requires hardware connection; the F function of the light super S box is constructed. The algorithm structure is highly symmetric, an encryption module is decrypted and multiplexed by the algorithm, decryption can be performed by exchanging an encryption round key use sequence, the operation is easy and convenient, and extra resource is not required to be consumed by the decryption. Compared with the current lightweight password, the occupied resource is smaller, the encryption performance is high, and known attack can be resisted.

The invention relates to a DWT-SVD geometric attack prevention blind watermark method based on SIFT. The method comprises a watermark embedding method and a watermark extraction method. The watermark embedding method includes the steps that discrete waterlet transformation is conducted on an original image, a low-frequency sub-band of the original image is divided into small blocks, singular value decomposition is conducted on each small block, chaotic encryption is conducted on watermarks to be embedded, and the watermarks are embedded into the maximum singular value of each small block through an optimal quantitative method, the SIFT feature points of a watermark image are stored as secret keys, the types of geometric attacks are judged according to the secret keys, and correction is conducted. The watermark extraction method is the inverse process of the watermark embedding method and includes the steps of correction of attacked images, watermark extraction and watermark decryption and restoration. According to the method, by the utilization of the rotation, zoom and translation invariance of the SIFT feature points and the combination of the advantages of DWT and SVD in the digital watermark aspect, robustness on geometric attacks is remarkably improved.

The invention provides a method for optimizing medical image classification performance based on a generative adversarial network. The method comprises the steps of constructing a classification taskdata set; training a classification algorithm model on the existing data; generating new positive sample candidate data by using the generative adversarial network; strictly screening the generated positive sample data by utilizing a voting mechanism; and fusing the generated data into the existing positive sample data fine tuning classification network according to a certain proportion. The medical image classification method has the technical advantages that the problems of poor algorithm generalization capability, easy overfitting, high manual data accumulation cost and the like caused by small positive sample data size in medical image classification are solved. In addition, the anti-attack capability of the algorithm can be improved to a certain extent while the performance of the medical image classification algorithm is improved.

The invention relates to an embedding method and an extracting method for a text watermark based on semantic role position mapping. The embedding method comprises the following steps: 1) preprocessing the watermark information and converting a watermark character into code elements and forming an information string; 2) utilizing a natural language processing technique to search for the semantic role in the text, thereby acquiring the position information of the semantic role, and causing the semantic role category to be corresponding to the code elements one by one; 3) taking out the codes from the information string of the watermark one by one, mapping the codes to the position corresponding to the category of the semantic role, thereby finishing the embedding of the watermark. The extracting method comprises the following steps: searching for the semantic role on the position in the text according to the position information of the semantic role which is acquired during the process of watermark embedding; reversely mapping, thereby acquiring the information string of the watermark expressed by the code elements; lastly, converting the information string into the original watermark information. According to the method provided by the invention, the text format and content are free from any alteration, the hidden property and the robustness are excellent, and various conventional format conversions and attacks can be effectively resisted.

The invention relates to a scanner having functions of digital copyright protection and scan source tracing, comprising: a digital watermark creating module for creating a digital watermark; a discrete cosine transform module for processing scan data to prepare for subsequent watermark embedding; a digital watermark embedding module for embedding the digital watermark into a scan data; and a discrete cosine inverse transform module for hiding the digital watermark. The scan method comprises the following steps of: creating a digital watermark based on the scan associated information as a resource mark; calling the scan data of the discrete cosine transform process, adding the digital watermark into a discrete cosine transform frequency domain space; embedding the digital watermark after the chaotic process into a scan data; and calling a discrete cosine inverse transform to hide the digital watermark.

The invention belongs to the field of artificial neural network protection mechanisms, and relates to a neural network model encryption protection system and method involving domain transformation data encryption. The system comprises an encryption module; a frequency domain transformation module in the encryption module is used for transforming original input data into a two-dimensional structure, conducting domain transformation on the original input data obtained after structure transformation and transforming the original input data in the space domain into original frequency domain data in the frequency domain; a frequency domain data processing module in the encryption module is used for processing the original frequency domain data in a specific processing mode to generate encryptedfrequency domain data; and a frequency domain inverse transformation module in the encryption module is used for conducting inverse domain transformation corresponding to above-mentioned domain transformation on the encrypted frequency domain data and transforming the encrypted frequency domain data in the frequency domain into the encrypted input data in the space domain. According to the methodof achieving input data encryption through domain transformation, the concealment and the anti-attacking performance of password information are improved, and the security of a trained artificial neural network model can be improved.

The invention provides a multi-image encryption method based on fractional mellin transform. The method includes the steps of compressing multiple images according to a frequency spectrum cutting and splicing method, then, dividing an image obtained through compression into a plurality of sub-images according to an annular domain, conducting fractional mellin transform on all the sub-images, encrypting a fractional mellin transform outcome into a cryptograph image through magnitude and phase encoding, taking transform degrees of fractional mellin transform as secret keys, and taking a center coordinate for coordinate transform, an inner radius of the annular domain for implementation of transform and an outer radius of the annular domain for implementation of transform as secondary secret keys. According to the multi-image encryption method, the multiple images are compressed through the real-value characteristics of fractional cosine transform, and therefore overweight transmission loads are avoided, and the requirement for instantaneity of image data transmission is met. Fractional mellin transform is then conducted on the image obtained through compression, the fractional order characteristic, the nonlinear characteristic and the like of the fractional cosine transform are fully utilized, and the multi-image encryption method has quite high robustness in terms of clipping prevention and noise prevention. The nonlinear operation is introduced into an encryption system while multi-image encryption transmission can be ensured, and safety of the encryption system is enhanced.

The invention discloses a random number generator based on a transition effect ring oscillator. The random number generator consists of a random number core circuit which is used to generate an oscillation signal of unfixed time, and finally stabilizes at a fixed high level or low level; a control circuit which is used to generate resetting signals of the random number core circuit and a counter circuit; and a counter which enables the random number core circuit after the counter is reset, and is used for counting impulses generated by the random number core circuit. The invention has the advantages of a higher rate and a better anti-attack performance. The invention can be applied to all kinds of cryptosystems.

The invention discloses a data exchange system for onsite transaction processing, and the system comprises a micro-terminal induction card, a micro-terminal APP, a card reader, an application front end, an application server, and an issuing server. The micro-terminal induction card stores the identity recognition information, and the micro-terminal APP is a program which is installed on a mobile intelligent terminal and is used for identity authentication of a user and transaction processing. The issuing server is a program module which is used for the data exchange and the transaction processing. The card reader, the application front end and the application server form an application square block. The data exchange between the micro-terminal induction card and the micro-terminal APP is carried out through a circuit between the application front end and the application server and a circuit between the application front end and the issuing server. The invention also discloses a data exchange method for the onsite transaction processing, and the method comprises the steps: micro-terminal user registration and authentication, application access and marking, onsite transaction processing and abnormal transaction interception. The system can be used for replacing various types of payment cards, expense cards and identity verification cards, and is good in safety and resistance to attack.

The invention relates to a multi-image hiding method based on fractional mellin transform. According to the method, compression of multiple to-be-hidden images is carried out by utilizing a frequency spectrum cutting and splicing method, carrier images and compression images are respectively divided into multiple ring zone sub images, fractional mellin transform in different orders on each image is carried out, fusion of all results in a random combination mode is carried out by utilizing a primary Bezier curve, and fractional mellin transform is carried out by utilizing the same orders of carrier image transform to acquire fusion images containing to-be-hidden image information. The orders of fractional mellin transform and the fusion coefficients are taken as secret keys, and a center coordinate of coordinate transform and an inner radius and an outer radius for carrying out ring zone transform are taken as secondary secret keys. The method utilizes real property of discrete cosine transform to realize compression of the multiple images, increases hidden information amount in a frequency domain processing method, utilizes fractional mellin transform for encryption and improves anti-attacking capability and safety of systems.

The invention discloses a novel brain-controlled intelligent rehabilitation method based on a capsule network, and application thereof. According to the method, an upper computer generates corresponding motion stimulation videos according to rehabilitation training items selected by a user, the motion stimulation videos are displayed to the user through a displayer, the user imagines correspondingactions, and synchronous motion imagination electroencephalogram signals of the user are collected through an electroencephalogram collecting device, subjected to amplifying and filtering preprocessing and transmitted to the upper computer in a wireless mode; after the upper computer receives the motion imagery electroencephalogram signals and processes the motion imagery electroencephalogram signals again, the features of the motion imagery electroencephalogram signals are extracted based on a capsule network algorithm, and are classified, the classification results are converted into corresponding rehabilitation training control signals, and the rehabilitation training control signals are transmitted to a rehabilitation exercise device; the rehabilitation exercise device drives the userto perform corresponding training actions and feeds back signal data of the training actions of the user to the upper computer; and the upper computer evaluates the signal data of the training actions of the user by adopting a Fugl-Meyer evaluation method. The safety of the brain-controlled rehabilitation system can be improved.

The invention relates to an electric power material coding optimization method based on a hash algorithm. The method comprises steps of mixing the secret key with the message data by using an HMAC-MD5algorithm constructed on the basis of an MD5 message digest algorithm, performing hash calculation on a mixed result by using a hash function, mixing an obtained hash value with the secret key, and then applying the hash function again; and enabling the HMAC-MD5 to receive a secret key with any size and generate a hash sequence with the length of 128 bits. According to the invention, the hash algorithm is combined on the basis of the existing electric power material coding mode, and the electric power material coding security strength based on the HMAC-MD5 algorithm is high; codes based on anHMAC-MD5 algorithm and IPv6 are fused, codes generated based on a coding mode of the HMAC-MD5 algorithm are added with a secret key, an IPv6 address generated by a hash value with the secret key is fused, and the better anti-attack capacity is achieved.

The invention provides a watermark embedding method and device and a watermark extracting method and device, and belongs to the technical field of digital image processing and information security. The watermark embedding method comprises the following steps: acquiring an original watermark image and an original video; acquiring a video watermark by using the original watermark image; and embedding the video watermark frame by frame in the video frame of the original video through a method of modifying a pixel value, and converting the video frame embedded with the video watermark into a watermark video. According to the technical scheme, video invisible watermark embedding can be realized.