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Secure Transmission of Compressed Medical Image Sequences on Communication Networks Using Motion Vector Watermarking
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作者 Rafi Ullah Mohd Hilmi bin Hasan +1 位作者 Sultan Daud Khan Mussadiq Abdul Rahim 《Computers, Materials & Continua》 SCIE EI 2024年第3期3283-3301,共19页
Medical imaging plays a key role within modern hospital management systems for diagnostic purposes.Compression methodologies are extensively employed to mitigate storage demands and enhance transmission speed,all whil... Medical imaging plays a key role within modern hospital management systems for diagnostic purposes.Compression methodologies are extensively employed to mitigate storage demands and enhance transmission speed,all while upholding image quality.Moreover,an increasing number of hospitals are embracing cloud computing for patient data storage,necessitating meticulous scrutiny of server security and privacy protocols.Nevertheless,considering the widespread availability of multimedia tools,the preservation of digital data integrity surpasses the significance of compression alone.In response to this concern,we propose a secure storage and transmission solution for compressed medical image sequences,such as ultrasound images,utilizing a motion vector watermarking scheme.The watermark is generated employing an error-correcting code known as Bose-Chaudhuri-Hocquenghem(BCH)and is subsequently embedded into the compressed sequence via block-based motion vectors.In the process of watermark embedding,motion vectors are selected based on their magnitude and phase angle.When embedding watermarks,no specific spatial area,such as a region of interest(ROI),is used in the images.The embedding of watermark bits is dependent on motion vectors.Although reversible watermarking allows the restoration of the original image sequences,we use the irreversible watermarking method.The reason for this is that the use of reversible watermarks may impede the claims of ownership and legal rights.The restoration of original data or images may call into question ownership or other legal claims.The peak signal-to-noise ratio(PSNR)and structural similarity index(SSIM)serve as metrics for evaluating the watermarked image quality.Across all images,the PSNR value exceeds 46 dB,and the SSIM value exceeds 0.92.Experimental results substantiate the efficacy of the proposed technique in preserving data integrity. 展开更多
关键词 Block matching algorithm(BMA) compression full-search algorithm motion vectors ultrasound image sequence watermarking
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A New Image Watermarking Scheme Using Genetic Algorithm and Residual Numbers with Discrete Wavelet Transform
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作者 Peter Awonnatemi Agbedemnab Mohammed Akolgo Moses Apambila Agebure 《Journal of Information Security》 2023年第4期422-436,共15页
Transmission of data over the internet has become a critical issue as a result of the advancement in technology, since it is possible for pirates to steal the intellectual property of content owners. This paper presen... Transmission of data over the internet has become a critical issue as a result of the advancement in technology, since it is possible for pirates to steal the intellectual property of content owners. This paper presents a new digital watermarking scheme that combines some operators of the Genetic Algorithm (GA) and the Residue Number (RN) System (RNS) to perform encryption on an image, which is embedded into a cover image for the purposes of watermarking. Thus, an image watermarking scheme uses an encrypted image. The secret image is embedded in decomposed frames of the cover image achieved by applying a three-level Discrete Wavelet Transform (DWT). This is to ensure that the secret information is not exposed even when there is a successful attack on the cover information. Content creators can prove ownership of the multimedia content by unveiling the secret information in a court of law. The proposed scheme was tested with sample data using MATLAB2022 and the results of the simulation show a great deal of imperceptibility and robustness as compared to similar existing schemes. 展开更多
关键词 Discrete Wavelet Transform (DWT) Digital watermarking Encryption Genetic algorithm (GA) Residue Number System (RNS) GARN
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A Weighted Algorithm for Watermarking Relational Databases 被引量:2
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作者 CUI Xinchun QIN Xiaolin SHENG Gang 《Wuhan University Journal of Natural Sciences》 CAS 2007年第1期79-82,共4页
A weighted algorithm for watermarking relational databases for copyright protection is presented. The possibility of watermarking an attribute is assigned according to its weight decided by the owner of the database. ... A weighted algorithm for watermarking relational databases for copyright protection is presented. The possibility of watermarking an attribute is assigned according to its weight decided by the owner of the database. A one-way hash function and a secret key known only to the owner of the data are used to select tuples and bits to mark. By assigning high weight to significant attributes, the scheme ensures that important attributes take more chance to be marked than less important ones. Experimental results show that the proposed scheme is robust against various forms of attacks, and has perfect immunity to subset attack. 展开更多
关键词 weighted algorithm watermarking relational databases copyright protection
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A blind watermarking algorithm based on DWT and SVD 被引量:2
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作者 XUAN Chun-qing XUAN Zhi-wei +1 位作者 ZHANG Xia CHEN Bao-li 《Journal of Measurement Science and Instrumentation》 CAS 2014年第2期31-35,共5页
This paper presents a new digital image blind watermarking algorithm based on combination of discrete wavelet transform (DWT) and singular value decomposition (SVD). First of all, we make wavelet decomposition for... This paper presents a new digital image blind watermarking algorithm based on combination of discrete wavelet transform (DWT) and singular value decomposition (SVD). First of all, we make wavelet decomposition for the original image and divide the acquired low frequency sub-band into blocks. Then we make singular value decomposition for each block and embed the watermark information in the largest singular value by quantitative method. The watermark can be extracted without the original image. The experimental results show that the algorithm has a good imperceptibility and robustness. 展开更多
关键词 discrete wavelet transform singular value decomposition a blind watermarking algorithm ROBUSTNESS
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New Optimal DWT Domain Image Watermarking Technique via Genetic Algorithm
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作者 钟宁 匡镜明 何遵文 《Journal of Beijing Institute of Technology》 EI CAS 2007年第4期465-470,共6页
A novel optimal image watermarking scheme is proposed in which the genetic algorithm (GA) is employed to obtain the improvement of algorithm performance. Arnold transform is utilized to obtain the scrambled watermark,... A novel optimal image watermarking scheme is proposed in which the genetic algorithm (GA) is employed to obtain the improvement of algorithm performance. Arnold transform is utilized to obtain the scrambled watermark, and then the embedding and extraction of watermark are implemented in digital wavelet transform (DWT) domain. During the watermarking process, GA is employed to search optimal parameters of embedding strength and times of Arnold transform to gain the optimization of watermarking performance. Simulation results show that the proposed method can improve the quality of watermarked image and give almost the same robustness of the watermark. 展开更多
关键词 image watermarking genetic algorithm (GA) digital wavelet transform (DWT)
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Audio Watermarking Using Wavelet Transform and Genetic Algorithm for Realizing High Tolerance to MP3 Compression
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作者 Shinichi Murata Yasunari Yoshitomi Hiroaki Ishii 《Journal of Information Security》 2011年第3期99-112,共14页
Recently, several digital watermarking techniques have been proposed for hiding data in the frequency domain of audio signals to protect the copyrights. However, little attention has been given to the optimal position... Recently, several digital watermarking techniques have been proposed for hiding data in the frequency domain of audio signals to protect the copyrights. However, little attention has been given to the optimal position in the frequency domain for embedding watermarks. In general, there is a tradeoff between the quality of the watermarked audio and the tolerance of watermarks to signal processing methods, such as compression. In the present study, a watermarking method developed for a visual image by using a wavelet transform was applied to an audio clip. We also improved the performance of both the quality of the watermarked audio and the extraction of watermarks after compression by the MP3 technique. To accomplish this, we created a multipurpose optimization problem for deciding the positions of watermarks in the frequency domain and obtaining a near-optimum solution. The near-optimum solution is obtained by using a genetic algorithm. The experimental results show that the proposed method generates watermarked audios of good quality and high tolerance to MP3 compression. In addition, the security was improved by using the characteristic secret key to embed and extract the watermark information. 展开更多
关键词 AUDIO watermarking GENETIC algorithm Optimization WAVELET Transforms SECRET Key
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Reversible Digital Image Watermarking Scheme Using Bit Replacement and Majority Algorithm Technique
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作者 Koushik Pal Goutam Ghosh Mahua Bhattacharya 《Journal of Intelligent Learning Systems and Applications》 2012年第3期199-206,共8页
The current paper presents a new digital watermarking method through bit replacement technology, which stores mul-tiple copies of the same data that is to be hidden in a scrambled form in the cover image. In this pape... The current paper presents a new digital watermarking method through bit replacement technology, which stores mul-tiple copies of the same data that is to be hidden in a scrambled form in the cover image. In this paper an indigenous approach is described for recovering the data from the damaged copies of the data under attack by applying a majority algorithm to find the closest twin of the embedded information. A new type of non-oblivious detection method is also proposed. The improvement in performance is supported through experimental results which show much enhancement in the visual and statistical invisibility of hidden data. 展开更多
关键词 Additive Noise Salt and PEPPER Noise Compression Filtering AVERAGING Multiple watermarking MAJORITY algorithm
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A robust tensor watermarking algorithm for diffusion-tensor images
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作者 Chengmeng LIU Zhi LI +1 位作者 Guomei WANG Long ZHENG 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2024年第3期384-397,共14页
Watermarking algorithms that use convolution neural networks have exhibited good robustness in studies of deep learning networks.However,after embedding watermark signals by convolution,the feature fusion eficiency of... Watermarking algorithms that use convolution neural networks have exhibited good robustness in studies of deep learning networks.However,after embedding watermark signals by convolution,the feature fusion eficiency of convolution is relatively low;this can easily lead to distortion in the embedded image.When distortion occurs in medical images,especially in diffusion tensor images(DTIs),the clinical value of the DTI is lost.To address this issue,a robust watermarking algorithm for DTIs implemented by fusing convolution with a Transformer is proposed to ensure the robustness of the watermark and the consistency of sampling distance,which enhances the quality of the reconstructed image of the watermarked DTIs after embedding the watermark signals.In the watermark-embedding network,Ti-weighted(Tlw)images are used as prior knowledge.The correlation between T1w images and the original DTI is proposed to calculate the most significant features from the T1w images by using the Transformer mechanism.The maximum of the correlation is used as the most significant feature weight to improve the quality of the reconstructed DTI.In the watermark extraction network,the most significant watermark features from the watermarked DTI are adequately learned by the Transformer to robustly extract the watermark signals from the watermark features.Experimental results show that the average peak signal-to-noise ratio of the watermarked DTI reaches 50.47 dB,the diffusion characteristics such as mean diffusivity and fractional anisotropy remain unchanged,and the main axis deflection angleαAc is close to 1.Our proposed algorithm can effectively protect the copyright of the DTI and barely affects the clinical diagnosis. 展开更多
关键词 Robust watermarking algorithm Transformer Image reconstruction Diffusion tensor images Soft attention Hard attention Tl-weighted images
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A Robust Watermarking Scheme Based on ROI and IWT for Remote Consultation of COVID-19 被引量:4
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作者 Xiaorui Zhang Wenfang Zhang +2 位作者 Wei Sun Tong Xu Sunil Kumar Jha 《Computers, Materials & Continua》 SCIE EI 2020年第9期1435-1452,共18页
In the current dire situation of the corona virus COVID-19,remote consultations were proposed to avoid cross-infection and regional differences in medical resources.However,the safety of digital medical imaging in rem... In the current dire situation of the corona virus COVID-19,remote consultations were proposed to avoid cross-infection and regional differences in medical resources.However,the safety of digital medical imaging in remote consultations has also attracted more and more attention from the medical industry.To ensure the integrity and security of medical images,this paper proposes a robust watermarking algorithm to authenticate and recover from the distorted medical images based on regions of interest(ROI)and integer wavelet transform(IWT).First,the medical image is divided into two different parts,regions of interest and non-interest regions.Then the integrity of ROI is verified using the hash algorithm,and the recovery data of the ROI region is calculated at the same time.Also,binary images with the basic information of patients are processed by logistic chaotic map encryption,and then the synthetic watermark is embedded in the medical carrier image using IWT transform.The performance of the proposed algorithm is tested by the simulation experiments based on the MATLAB program in CT images of the lungs.Experimental results show that the algorithm can precisely locate the distorted areas of an image and recover the original ROI on the basis of verifying image reliability.The maximum peak signal to noise ratio(PSNR)value of 51.24 has been achieved,which proves that the watermark is invisible and has strong robustness against noise,compression,and filtering attacks. 展开更多
关键词 Digital watermarking LOGISTIC hash algorithm ROI IWT
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QIM digital watermarkingbased on LDPC code and messagepassingunder scalingattacks
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作者 崔鑫 颜斌 +1 位作者 贾霞 王亚菲 《Journal of Measurement Science and Instrumentation》 CAS 2014年第1期37-40,共4页
Watermarking system based on quantization index modulation (QIM) is increasingly popular in high payload applications,but it is inherently fragile against amplitude scaling attacks.In order to resist desynchronizati... Watermarking system based on quantization index modulation (QIM) is increasingly popular in high payload applications,but it is inherently fragile against amplitude scaling attacks.In order to resist desynchronization attacks of QIM digital watermarking,a low density parity check (LDPC) code-aided QIM watermarking algorithm is proposed,and the performance of QIM watermarking system can be improved by incorporating LDPC code with message passing estimation/detection framework.Using the theory of iterative estimation and decoding,the watermark signal is decoded by the proposed algorithm through iterative estimation of amplitude scaling parameters and decoding of watermark.The performance of the proposed algorithm is closer to the dirty paper Shannon limit than that of repetition code aided algorithm when the algorithm is attacked by the additive white Gaussian noise.For constant amplitude scaling attacks,the proposed algorithm can obtain the accurate estimation of amplitude scaling parameters.The simulation result shows that the algorithm can obtain similar performance compared to the algorithm without desynchronization. 展开更多
关键词 digital watermarking quantization index modulation (QIM) message passing algorithm based on factor graph low density parity check (LDPC) code amplitude scaling attack
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On Secure Digital Image Watermarking Techniques 被引量:2
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作者 Manjit Thapa Sandeep Kumar Sood 《Journal of Information Security》 2011年第4期169-184,共16页
Digital watermarking is used to hide the information inside a signal, which can not be easily extracted by the third party. Its widely used application is copyright protection of digital information. It is different f... Digital watermarking is used to hide the information inside a signal, which can not be easily extracted by the third party. Its widely used application is copyright protection of digital information. It is different from the encryption in the sense that it allows the user to access, view and interpret the signal but protect the ownership of the content. One of the current research areas is to protect digital watermark inside the information so that ownership of the information cannot be claimed by third party. With a lot of information available on various search engines, to protect the ownership of information is a crucial area of research. In latest years, several digital watermarking techniques are presented based on discrete cosine transform (DCT), discrete wavelets transform (DWT) and discrete fourier transforms (DFT). In this paper, we propose an algorithm for digital image watermarking technique based on singular value decomposition;both of the L and U components are explored for watermarking algorithm. This technique refers to the watermark embedding algorithm and watermark extracting algorithm. The experimental results prove that the quality of the watermarked image is excellent and there is strong resistant against many geometrical attacks. 展开更多
关键词 Digital Image watermarking SINGULAR Value Decomposition watermark Embedding algorithm watermark EXTRACTING algorithm Ratio ANALYSIS Security ANALYSIS
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Embedding and Extracting Digital Watermark Based on DCT Algorithm 被引量:1
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作者 Haiming Li Xiaoyun Guo 《Journal of Computer and Communications》 2018年第11期287-298,共12页
The principle of digital watermark is the method of adding digital watermark in the frequency domain. The digital watermark hides the watermark in digital media, such as image, voice, video, etc., so as to realize the... The principle of digital watermark is the method of adding digital watermark in the frequency domain. The digital watermark hides the watermark in digital media, such as image, voice, video, etc., so as to realize the functions of copyright protection, and identity recognition. DCT for Discrete Cosine Transform is used to transform the image pixel value and the frequency domain coefficient matrix to realize the embedding and extracting of the blind watermark in the paper. After success, the image is attacked by white noise and Gaussian low-pass filtering. The result shows that the watermark signal embedded based on the DCT algorithm is relatively robust, and can effectively resist some attack methods that use signal distortion to destroy the watermark, and has good robustness and imperceptibility. 展开更多
关键词 Digital watermark DCT algorithm White Noise GAUSSIAN LOW-PASS Filtering Robustness IMPERCEPTIBILITY
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High Efficiency Crypto-Watermarking System Based on Clifford-Multiwavelet for 3D Meshes Security
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作者 Wajdi Elhamzi Malika Jallouli Yassine Bouteraa 《Computers, Materials & Continua》 SCIE EI 2022年第11期4329-4347,共19页
Since 3D mesh security has become intellectual property,3D watermarking algorithms have continued to appear to secure 3D meshes shared by remote users and saved in distant multimedia databases.The novelty of our appro... Since 3D mesh security has become intellectual property,3D watermarking algorithms have continued to appear to secure 3D meshes shared by remote users and saved in distant multimedia databases.The novelty of our approach is that it uses a new Clifford-multiwavelet transform to insert copyright data in a multiresolution domain,allowing us to greatly expand the size of the watermark.After that,our method does two rounds of insertion,each applying a different type of Clifford-wavelet transform.Before being placed into the Clifford-multiwavelet coefficients,the watermark,which is a mixture of the mesh description,source mesh signature(produced using SHA512),and a logo encrypted using the RSA(Ronald Shamir Adleman)technique,is encoded using Turbo-code.Using the Least Significant Bit method steps,data embedding involves modulation and insertion processes.Finally,the watermarked mesh is reconstructed using the inverse Cliffordmultiwavelet transform.Due to the utilization of a hybrid insertion domain,our technique has demonstrated a very high insertion rate while retaining mesh quality.The mesh is watermarked,and the extracted data is acquired in real-time.Our approach is also resistant to the most common types of attacks.Our findings reveal that the current approach improves on previous efforts. 展开更多
关键词 Digital watermarking Clifford-multiwavelet transform Multiwavelet entropy LSB method RSA algorithm RSA algorithm Turbocode 3D multiresolution meshes
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Watermarking Images in the Frequency Domain by Exploiting Self-Inverting Permutations
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作者 Maria Chroni Angelos Fylakis Stavros D. Nikolopoulos 《Journal of Information Security》 2013年第2期80-91,共12页
In this work we propose efficient codec algorithms for watermarking images that are intended for uploading on the web under intellectual property protection. Headed to this direction, we recently suggested a way in wh... In this work we propose efficient codec algorithms for watermarking images that are intended for uploading on the web under intellectual property protection. Headed to this direction, we recently suggested a way in which an integer number w which being transformed into a self-inverting permutation, can be represented in a two dimensional (2D) object and thus, since images are 2D structures, we have proposed a watermarking algorithm that embeds marks on them using the 2D representation of w in the spatial domain. Based on the idea behind this technique, we now expand the usage of this concept by marking the image in the frequency domain. In particular, we propose a watermarking technique that also uses the 2D representation of self-inverting permutations and utilizes marking at specific areas thanks to partial modifications of the image’s Discrete Fourier Transform (DFT). Those modifications are made on the magnitude of specific frequency bands and they are the least possible additive information ensuring robustness and imperceptiveness. We have experimentally evaluated our algorithms using various images of different characteristics under JPEG compression. The experimental results show an improvement in comparison to the previously obtained results and they also depict the validity of our proposed codec algorithms. 展开更多
关键词 watermarking Techniques Image watermarking algorithms Self-Inverting PERMUTATIONS 2D REPRESENTATIONS of PERMUTATIONS ENCODING DECODING Frequency Domain Experimental Evaluation
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基于语义的无线水印安全通信技术验证
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作者 樊仁和 苟文龙 武刚 《移动通信》 2024年第2期97-103,共7页
随着近年来计算机网络技术、通信技术以及数字处理技术的飞速发展,互联网与人们的生活紧密相联。在带来极大便利的同时,也存在着各类信息窃取与版权盗用事件,数字水印技术应运而生。为达到鲁棒性与透明性的最优平衡,提出了一种基于语义... 随着近年来计算机网络技术、通信技术以及数字处理技术的飞速发展,互联网与人们的生活紧密相联。在带来极大便利的同时,也存在着各类信息窃取与版权盗用事件,数字水印技术应运而生。为达到鲁棒性与透明性的最优平衡,提出了一种基于语义的无线水印安全通信技术。首先通过融合语义内容信息,达到提升数字水印通信的安全性的目的。其次分析了DWT、DCT、DFT等传统水印的不足,并采用遗传算法优化的方式来完善数字水印技术。这一过程中,还涵盖了使用基础和多层自编码器生成数字水印的方法,实现了基于DCT-DWT-SVD的数字水印算法以及相应遗传算法优化,以达到鲁棒性和透明性之间的最佳平衡。最后,论文还根据802.11a协议,为SDR平台设计了相应的发射机和接收机,全面展示了整个通信过程。 展开更多
关键词 数字水印 语义信息 自编码器 遗传算法 DCT-DWT-SVD 802.11a协议 通信安全
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新颖的内容自适应图像篡改检测与自恢复算法研究
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作者 李明月 毕秀丽 刘波 《重庆邮电大学学报(自然科学版)》 CSCD 北大核心 2024年第4期797-806,共10页
针对在原始图像中嵌入大量的水印(认证水印和参考水印)容易造成图像失真的问题,提出嵌入少量参考水印的方法。为了减小图像失真,提出将少量的参考水印信息嵌入在原始图像的边缘、轮廓等区域的方法。在恢复篡改区域时,提出利用图像修复... 针对在原始图像中嵌入大量的水印(认证水印和参考水印)容易造成图像失真的问题,提出嵌入少量参考水印的方法。为了减小图像失真,提出将少量的参考水印信息嵌入在原始图像的边缘、轮廓等区域的方法。在恢复篡改区域时,提出利用图像修复算法将篡改块匹配问题转化为非局部自相似图像块的最小化问题,复制攻击图像本身的相似信息来恢复篡改区域。实验结果表明,在水印容量为0.015626的情况下,该算法得到嵌入水印后图像的峰值信噪比(peak signal to noise ratio,PSNR)均值超过60 dB,恢复图像的PSNR均值超过40 dB。 展开更多
关键词 水印 图像恢复 图像修复算法 篡改检测 自恢复
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基于双混沌映射的遥感图像零水印算法
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作者 杨兵兵 闫浩文 +4 位作者 张黎明 徐欣钰 王小龙 严清博 侯昭阳 《地理与地理信息科学》 CSCD 北大核心 2024年第3期21-28,共8页
现有遥感图像零水印算法多为特定类型的遥感图像设计,普适性较差,且对水印组合攻击的鲁棒性不强。该文提出一种基于双混沌映射的遥感图像零水印算法。①对遥感图像进行非下采样剪切波变换,选取低频图像进行离散余弦变换;②对变换后的图... 现有遥感图像零水印算法多为特定类型的遥感图像设计,普适性较差,且对水印组合攻击的鲁棒性不强。该文提出一种基于双混沌映射的遥感图像零水印算法。①对遥感图像进行非下采样剪切波变换,选取低频图像进行离散余弦变换;②对变换后的图像进行分块,并对各子块进行Schur分解,通过比较每个子块上三角矩阵中第一个元素值和均值的大小构建特征矩阵;③利用一维Logistic映射置乱遥感图像,与特征矩阵进行异或运算得到一个二值序列;①结合2D-LALM-Tent映射和Arnold置乱水印图像,对前述二值序列和置乱后水印的二值序列进行异或运算得到零水印。实验表明,该算法对不同类型遥感图像的适用性较好,且对水印组合攻击的鲁棒性较强,无精度损失,可用于多种类型遥感图像的版权保护,为遥感图像的共享提供安全保障。 展开更多
关键词 双混沌映射 2D-LALM TENT映射 遥感图像 零水印算法
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基于像素不扩展视觉密码的光学彩色脆弱水印
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作者 刘睿泽 祝玉鹏 +5 位作者 周新隆 米沼锞 吴承哲 秦俏华 柯常军 史祎诗 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第13期126-134,共9页
本文提出了一种基于像素不扩展视觉密码的光学彩色脆弱水印系统.一方面,使用像素不扩展视觉密码对水印图像进行编码,避免了因视觉密码引起的像素扩展问题,使得后续可以选择与水印图像具有相同像素大小的彩色宿主图像,大大减少了传输过... 本文提出了一种基于像素不扩展视觉密码的光学彩色脆弱水印系统.一方面,使用像素不扩展视觉密码对水印图像进行编码,避免了因视觉密码引起的像素扩展问题,使得后续可以选择与水印图像具有相同像素大小的彩色宿主图像,大大减少了传输过程中所占用的网络带宽以及存储空间.另一方面,使用相位恢复算法对编码后水印图像进行处理得到用于嵌入宿主图像的相位信息,以光学的方式进一步提高水印图像的安全性.使用计算机模拟验证所提光学彩色脆弱水印的可行性、不可感知性,并通过一系列仿真攻击实验验证所提水印具有良好的脆弱性,在面对噪声污染以及旋转、运动模糊处理、滤波等常见的攻击下均可灵敏地检测出图像发生了篡改. 展开更多
关键词 光学彩色脆弱水印 像素不扩展视觉密码 相位恢复算法 篡改检测
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基于加密全息技术的试卷管理系统设计与研究 被引量:2
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作者 马婷 《现代电子技术》 2023年第11期93-98,共6页
针对传统的纸质考试操作过程复杂,电子化试卷面临各种网络攻击技术,为确保试卷进行数字化安全性与保密性的管理,设计基于加密全息技术的试卷管理系统。通过Java语言与MySQL数据库设计一个能够同时支持学生、教师与管理员登录的系统对试... 针对传统的纸质考试操作过程复杂,电子化试卷面临各种网络攻击技术,为确保试卷进行数字化安全性与保密性的管理,设计基于加密全息技术的试卷管理系统。通过Java语言与MySQL数据库设计一个能够同时支持学生、教师与管理员登录的系统对试卷进行所需要的管理与操作,与此同时把数字全息技术与Contourlet⁃SVD结合起来,设计出以Contourlet⁃SVD域数字全息为基础的水印加密算法,再将加密后的试卷录入系统后进行一系列管理。用户通过该系统不仅能够将试卷进行保存并通过系统自动生成试卷,还能够快捷便利地进行类似于试卷信息查询、增加、修改、删除等操作,以及相关信息的统计分析、保存等管理工作,全方位实现了对试卷的数字化、信息化、在线化的快速管理,有效地优化了教学管理的工作质量与工作效率。试卷在完成加密后用户通过登录模块进入系统,将完成加密的试卷进行录入与保存以便于后续的管理与使用。 展开更多
关键词 CONTOURLET变换 SVD 数字全息算法 试卷管理 Java 水印加密算法
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基于混沌加密的QR码彩色图像复合水印算法 被引量:3
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作者 马婷 李佳 《印刷与数字媒体技术研究》 CAS 北大核心 2023年第2期50-56,82,共8页
本研究提出了一种基于NSCT-DWT-SVD复合的QR码混沌加密彩色图像水印算法。首先将“飞行学院”四字组成的水印图像通过编码器进行QR编码生成QR码水印信息,再对水印进行Logistic混沌映射加密,将RGB颜色模型的原载体图像转换成YUV颜色模型... 本研究提出了一种基于NSCT-DWT-SVD复合的QR码混沌加密彩色图像水印算法。首先将“飞行学院”四字组成的水印图像通过编码器进行QR编码生成QR码水印信息,再对水印进行Logistic混沌映射加密,将RGB颜色模型的原载体图像转换成YUV颜色模型图像,对转换后的模型Y分量进行提取,将其进行NSCT生成低频分量,随后进行小波变换及SVD奇异值分解获得奇异值,最后将加密的QR码通过加性原理叠加到分解后的奇异值上。通过实验证明,该算法得到的峰值PSNR为52.15dB,保证了嵌入水印的信息量及隐蔽性,对椒盐噪音、JPEG压缩攻击NC值都为1,尤其是由于加入NSCT保证了图像的平移不变性,SVD更是提高了算法抵抗旋转攻击的能力。 展开更多
关键词 QR码 Logistic混沌映射加密 YUV NSCT DWT SVD 多重数字水印算法 彩色图像
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