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On Hiding Secret Information in Medium Frequency dct Components Using Least Significant Bits Steganography

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Computer Modeling in Engineering & Sciences 2019年第3期118卷 529-546页

作者： Sahib Khan M A Irfan Arslan Arif Syed Tahir Hussain Rizvi Asma Gul Muhammad Naeem Nasir Ahmad Department of Electronics and Telecommunications Politecnico di Torino10129 TorinoItaly Department of Computer Engineering University of LahorePakistan Department of Statistics Shaheed Benazir Bhutto Women University PeshawarPakistan Department of Computer Science University of PeshawarPakistan Department of Electronic and Electrical Engineering Loughborough UniversityUnited Kingdom

This work presents a new method of data hiding in digital images,in discrete cosine transform *** proposed method uses the least significant bits of the medium frequency components of the cover image for hiding the secret information,while the low and high frequency coefficients are kept *** unaltered low frequency dct coefficients preserves the quality of the smooth region of the cover image,while no changes in the high dct coefficient preserve the quality of the *** the medium frequency components have less contribution towards energy and image details,so the modification of these coefficients for data hiding results in high quality stego *** distortion due to the changes in the medium frequency coefficients is insignificant to be detected by the human visual *** proposed methods demonstrated a hiding capacity of 43:11%with the stego image quality of a peak signal to the noise ration of 36:3 dB,which is significantly higher than the threshold of 30 dB for a stego image *** proposed technique is immune to steganalysis and has proved to be highly secured against both spatial and dct domain steganalysis techniques.

关键词： dct steganography image processing information security data hiding steganalyisis

Robust Video Watermarking Using a Hybrid dct-DWT Approach

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Journal of Electronic Science and Technology 2020年第2期18卷 179-189页

作者： Jie Sang Qi Liu Chun-Lin Song School of Computer Science Jiangnan UniversityWuxi 214000

In order to solve the limitations of the digital video watermarking algorithm,this paper proposes a new robust video watermarking algorithm using combining discrete cosine transform(dct)and discrete wavelet transform(DWT)*** of all,the video frames are randomly selected and then the dct algorithm is applied to the selected video *** that,the first column of the selected video frames is scrambled using the Arnold ***,every column with 4 direct current(DC)coefficients is reshaped and transformed into four different sub-bands using the DWT ***,the watermark is embedded into the approximation(LL)*** proposed algorithm is easy to carry out because it provides random frames with no special requirements for video *** experiment results indicate that this algorithm can resist against different kinds of watermarking attacks,such as the Gaussian filter attack and sharpen *** addition,it also illustrates that the proposed algorithm has a better result than some other watermarking algorithms.

关键词： Arnold Hybrid dct

A Multi-Watermarking Algorithm for Medical Images Using Inception V3 and dct

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Computers, Materials & Continua 2023年第1期74卷 1279-1302页

作者： Yu Fan Jingbing Li Uzair Aslam Bhatti Chunyan Shao Cheng Gong Jieren Cheng Yenwei Chen School of Information and Communication Engineering Hainan UniversityHaikou570100China State Key Laboratory of Marine Resource Utilization in the South China Sea Hainan UniversityHaikou570100China School of Computer Science and Technology Hainan UniversityHaikou570100China Graduate School of Information Science and Engineering Ritsumeikan UniversityKyoto5258577Japan Hainan Blockchain Technology Engineering Research Center Hainan UniversityHaikou570100China TJ-YZ School of Network Science Haikou University of EconomicsHaikou571127China

Medical images are a critical component of the diagnostic process for *** the quality of medical photographs is essential to the accuracy of a physician’s diagnosis,they must be encrypted due to the characteristics of digital storage and information leakage associated with medical *** watermark embedding algorithm embeds the watermark information into the medical image,which reduces the quality of the medical image and affects the physicians’judgment of patient *** addition,watermarks in this method have weak robustness under high-intensity geometric attacks when the medical image is attacked and the watermarks are *** paper proposes a novel watermarking algorithm using the convolutional neural networks(CNN)Inception V3 and the discrete cosine transform(dct)to address above mentioned ***,the medical image is input into the Inception V3 network,which has been structured by adjusting parameters,such as the size of the convolution kernels and the typical architecture of the convolution ***,the coefficients extracted from the fully connected layer of the network are transformed by dct to obtain the feature vector of the medical *** last,the watermarks are encrypted using the logistic map system and hash function,and the keys are stored by a third *** encrypted watermarks and the original image features are performed logical operations to realize the embedding of *** the experimental section,multiple watermarking schemes using three different types of watermarks were implemented to verify the effectiveness of the three proposed *** NC values for all the images are more than 90%accurate which shows the robustness of the *** experimental results demonstrate the robustness under both conventional and high-intensity geometric attacks of the proposed algorithm.

关键词： Inception V3 multi-watermarking dct watermark encryption robustness

Double random number encryption blind watermarking technique based on DWT-dct domain

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Optoelectronics Letters 2024年第10期20卷 614-622页

作者： WANG Chenglong MA Yi WANG Xia National Engineering Research Center for Technology and Equipment of Environmental Deposition Lanzhou Jiaotong UniversityLanzhou730070China Key Laboratory of Opto-Technology and Intelligent Control Ministry of Education Lanzhou Jiaotong UniversityLanzhou730070China

Blind watermarking plays a significant role in copyright protection and information *** enhance the security of watermark image information,a dual encryption method is proposed,which combines block shuffling with Logistic chaos encryption using two sets of random numbers as *** dual encryption technique is applied to blind watermark images,utilizing a combination of discrete wavelet transform(DWT)and discrete cosine transform(dct)as the embedding ***,the watermark image is divided into small blocks,which are shuffled and rearranged using one set of random numbers as the key,while recording the shuffling sequence of block ***,the shuffled blocks are reassembled into an image,and another set of random numbers is used as the key for Logistic chaos encryption,rendering the watermark image chaotically ***,a double DWT is applied to the carrier image,followed by a dct,allowing the encrypted watermark image to be *** achieves the concealment of the blind *** results demonstrate that this method exhibits robustness,excellent invisibility,and secrecy.

关键词： random image dct

DVCast:denoising and variable dct for analog visual communications

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Digital Communications and Networks 2020年第4期6卷 471-479页

作者： Min Wang Bin Tan Dongmei Zhu Qin Zou The School of Mathematics and Computer Science Gannan Normal UniversityGanzhou341000China College of Electronics and Information Engineering Jinggangshan UniversityJi’an343009China Key Laboratory of Jiangxi Province for Numerical Simulation and Emulation Techniques Ganzhou341000China

Recently,analog visual transmission has attracted considerable attention owing to its graceful performance degradation for various wireless *** this study,we propose a novel analog visual communications system,named DVCast,in which an image denoising algorithm is used to fully utilize spatial correlation;moreover,the variable block size Discrete Cosine Transform(dct)is used to preserve more correlation information in an ***,there is a tradeoff between system performance and computing ***,to improve the real-time performance of the proposed system,implementation of Block Matching with 3D filtering(BM3D)and dct by Graphics Processing Units(GPUs)is *** to dct block size,i.e.,88,1616,and 3232,the schemes DVCast8,DVCast16,and DVCast32,respectively,are designed and *** show that DVCast with larger block size achieves better gain and visual quality than reference ***,it requires less computing ***32 outperforms conventional digital schemes by approximately 3.51 dB and achieves a 1.12 dB gain over state-of-the-art reference ***,the analysis shows that DVCast can reduce overhead by at least 75%.

关键词： Analog visual communications Image de-noising dct Graphics processing units

Grouped dct precoding for PAPR reduction in optical direct detection OFDM systems

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Optoelectronics Letters 2013年第3期9卷 213-216页

作者： WANG Zhong-peng ZHANG Shao-zhong School of Information and Electronic Engineering Zhejiang University of Science and Technology Hangzhou310023 China State Key Laboratory of Millimeter Waves Southeast University Nanjing 210096 China Faculty of Electronic and lnformation Engineering Zhejiang Wanli University Ningbo 315100 China

A new grouped precoding technique based on discrete cosine transform (dct) is presented for peak to average power ratio (PAPR) reduction of optical intensity modulated/direct detection (IM/DD) orthogonal frequency division multiplexing (OFDM) system. The computational complexity of the scheme is reduced by at least about 15% compared with that of the ordinary dct precoding scheme when the number of groups is 2. The PAPR with this method can be reduced by about 0.8 dB. Meantime, compared with original OFDM, the bit error rate (BER) performance of system is improved. So the proposed scheme for reducing PAPR is very effective in optical IM/DD OFDM systems.

关键词： OFDM系统 PAPR dct 分组预编码正交频分多路技术峰均功率比测光

A Fast Algorithm of the dct and Idct for VLSI Implementation

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A Fast Algorithm of the DCT and IDCT for VLSI Implementation

1996 3rd International Conference on Signal Processing(ICSP’96)

作者： Hong Ying Hou Zhaohuan Institute of Acoustics Chinese Academy of Sciences

ISBN: (纸本)0780329120

＜正＞Since dct performs very close to the statistically optimal Karhunen-Loeve Transform（KLT）,it is widely used in digital signal processing,especially for speech and image data *** dct algorithms and VLSI architectures for real-time computation capabilities are required *** is known that VLSI implementation of distributed arithmetic is very efficient for computing ***,an algorithm is presented to convert the dct and inverse dct（Idct） to *** implementation of the algorithm has same advantage as any implementation using distributed arithmetic.

关键词： VLSI discrete cosine transforms inverse problems transform coding digital signal processing chips data compression speech coding image coding digital arithmetic convolution number theory Idct dct VLSI implementation fast algorithm digital signal processing statistically optimal Karhunen-Loeve transform image data compression speech compression VLSI architectures real-time computation distributed arithmetic inverse dct skew-convolution number theoretic transforms

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dct域音频水印:嵌入对策和算法

电子学报 2006年第7期34卷 1260-1264页

作者：马翼平韩纪庆哈尔滨工业大学计算机科学与技术学院黑龙江哈尔滨150001

为保证dct域水印的鲁棒性,研究水印信号的嵌入位置非常必要.对音频载体,尽管有许多文献提出将水印嵌在中频系数或对听觉效果重要的系数上,但始终缺乏一个统一的方法.本文在dct噪声信号模型研究的基础上,提出了一种新的音频水印嵌入位置... 详细信息

为保证dct域水印的鲁棒性,研究水印信号的嵌入位置非常必要.对音频载体,尽管有许多文献提出将水印嵌在中频系数或对听觉效果重要的系数上,但始终缺乏一个统一的方法.本文在dct噪声信号模型研究的基础上,提出了一种新的音频水印嵌入位置选择策略和一个应用该策略的自适应音频水印算法.通过定义dct系数的噪声敏感度,建立了水印嵌入位置和嵌入水印后的音频信号的听觉感知性之间的关系,根据音频水印的不可听性的要求选择最优的嵌入位置,然后调节水印强度来满足鲁棒性的要求,从而最大程度地保持音频水印的不可听性和鲁棒性,为解决音频水印嵌入过程中不可听性和鲁棒性之间的矛盾提供了一种策略.应用该策略,本文提出了一个自适应音频水印算法.实验证实了算法的鲁棒性.

关键词：音频水印 dct 嵌入对策噪声敏感度

dct域自适应彩色图像二维数字水印算法研究

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计算机辅助设计与图形学学报 2004年第2期16卷 243-247页

作者：王向阳杨红颖辽宁师范大学计算机与信息技术学院大连116029

以离散余弦变换 (dct)、静态图像压缩编码、人眼视觉特性 (HVS)为基础 ,提出一种将灰度图像 (即二维数字水印 )嵌入到原始彩色图像中的新数字水印算法该算法具有以下特点 :(1)应用静态图像压缩编码技术实现了以二维数字水印作为水印... 详细信息

以离散余弦变换 (dct)、静态图像压缩编码、人眼视觉特性 (HVS)为基础 ,提出一种将灰度图像 (即二维数字水印 )嵌入到原始彩色图像中的新数字水印算法该算法具有以下特点 :(1)应用静态图像压缩编码技术实现了以二维数字水印作为水印信号的数字水印算法 ;(2 )充分利用HVS实现了二维数字水印的自适应嵌入 ,增强了算法的透明性和鲁棒性 ;(3)能够依据原始彩色载体图像内容实现数字水印嵌入深度的智能调节实验结果表明 :文中算法不仅具有较好的透明性 ,而且对如叠加噪声、JPEG压缩、平滑滤波、几何剪切、图像增强。

关键词： dct 自适应彩色图像数字水印离散余弦变换图像压缩鲁棒性图像编码