共查询到20条相似文献,搜索用时 62 毫秒
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一种简便易行的空间域图像信息隐藏技术 总被引:1,自引:0,他引:1
介绍了一种基于空间域的信息隐藏方案。在该方案中,通过对水印像点的位置进行随机置乱,达到加密的目的。考虑到了人类视觉系统特性,并根据图像块的特点自适应地改变嵌入信息的强度,使水印具有更好的不可见性。同时,将水印点嵌入到图像块中的位置进行随机置乱,提高了水印的安全性以及稳健性。该算法非常简便易行,而且实验证明,该算法是有效的。 相似文献
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利用边信息嵌入的CDMA水印信道性能研究 总被引:9,自引:0,他引:9
稳健性是数字水印的重要指标之一.为了改善水印稳健性,CDMA技术已被引入到数字水印中.但是,目前基于CDMA扩频技术的水印算法基本都是通过实验方式来确定嵌入强度以及相关参数.本文分析了把载体作为边信息情况下CDMA水印信道的性能.研究了PSNR值,嵌入强度参数 β ,正交码码长N以及用户数K之间的关系,给出了 PSNR关于这三者的显式表达式.根据PSNR值,给出了水印嵌入强度参数 β 的估计算法,仿真实验结果表明估计的有效性.并指出CDMA水印信道中,用户数不影响PSNR值的大小,实验结果有力地支持了这个结论.通过分析CDMA水印信道的误码形成过程,给出了信道误码率表达式,并得出,在给定PSNR值的情况下,CDMA正交扩频码码长 N 的选择不影响信道误码率值. 相似文献
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基于神经网络检测的自同步隐蔽信息传输系统 总被引:1,自引:0,他引:1
提出一种基于神经网络检测的自同步隐蔽信息传输系统,该系统满足以下特点:利用人的听觉系统分辨率限制实现隐藏信息伪装性传输,能有效克服传统加密通信易被攻击者监听、截取的缺点:先应用神经网络提取嵌入到语音中的数据,再进行相关检测确定自同步信号的存在。与直接提取数据后进行相关检测的方法相比.该方法能有效降低比特误码率,从而降低漏检和虚检概率,使隐藏信息的准确传输率明显提高。 相似文献
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基于DCT域QIM的音频信息伪装算法 总被引:1,自引:0,他引:1
音频与图像相比具有信息冗余大、随机性强的特点,在音频中实现无误码的信息提取的难度更大.提出一种基于DCT域QIM(quantization index modulation)的音频信息伪装算法,算法特点如下:应用QIM原理,以量化的方式嵌入信息,根据量化区间与信息比特的映射关系提取信息,可实现盲提取;采用改进的QIM方案,针对信息提取的误码,在嵌入端与提取端进行容错处理,保证了隐藏信息的强顽健性;隐藏容量大,可达357.6biffs.实验表明,算法与传统QIM方法相比具有更好的不可感知性,100%嵌入的载密音频的信噪比在30dB以上,并且对于MP3压缩、重量化、重采样、低通滤波等攻击具有很强的顽健性,同时算法运算量小,易于实现,实用性强. 相似文献
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提出一种图像自嵌入的水印算法.它将一个图像的主要内容嵌入该图像自身之中.该算法不仅能检测和定位对图像的窜改,而且能恢复被损坏的图像内容.算法的基本思路是把一个图像块的主要DCT系数经过量化、编码和加密后,嵌入另一个图像块的最低位之中.依据大量图像DCT量化系数的统计性质,本文仔细设计了主要DCT系数的编码表,使它既能满足水印负荷的要求,又能保证图像恢复时有较好的质量.分析了水印嵌入块和原图像块间偏移值应该满足的条件和设计方法.该算法为单向、不可逆的,可以抵抗可能的伪造攻击. 相似文献
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NTFS流是NTFS文件系统非常实用的功能,可以把文件的很多非常规属性以流的形式进行表达,但同时也提供了一种数据隐藏的方式,数据以NTFS流的方式进行隐藏在Windows操作系统中比较常见。文章通过分析NTFS交换数据流原理,重点研究以NTFS流进行数据隐藏的若干种形式,提出了有针对性的数据分析检验方法和线索发现手段,为相关应用行业提供技术依据。 相似文献
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针对大多可逆信息隐藏算法嵌入容量较小、通用 性差、运算量大等问题,文中在研究图像插值和可逆信息隐藏技 术基础上,设计了两种简单高效可逆信息隐藏算法,首先设计了一种类线性图像插值方法, 通过对插值数据分析测试,给出 理想插值图像的期望插值,以期望插值为目标,根据载体图像大小和秘密信息长度共同确定 出嵌入量控制阈值,再由混沌序 列动态生成每个插值像素中可嵌入秘密信息位数,实现秘密信息嵌入,然后通过差值调整因 子使最终插值最大限度接近期望 插值,保证载密图像有较高质量,整个过程无附加信息、无数据溢出、且能保证可逆性。当 采用恒定量嵌入时,嵌入率为 0.75T bit/pixel,T∈[ 1,4]最大嵌入 率可达到3bit/pixel;采用随机量嵌入时,可调节性更强,秘密信息更为分散,载密图像 质量更高。选取不同载体图像、在不同参数环境下对本文算法进行了大量实验,并与5个优 秀算法作了对比,算法有一定优越性。 相似文献
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This paper discusses a system test for digital DBS system with respect to audio and video signals. The test includes system delay, lip sync, service interruption time, audio quality, and video quality. The first three tests are implemented quantitatively, and the last two tests are implemented subjectively. The criteria for the system test are defined, its test methodology is discussed and its test results are analyzed 相似文献
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《Signal Processing: Image Communication》2014,29(10):1171-1180
Watermarking and data hiding are important tools for copyright protection of digital media contents. To reduce the interference effect of the host signal and improve the decoding performance in the popular additive Spread Spectrum (ASS) embedding scheme, we have proposed a novel correlation-and-bit-aware additive Spread Spectrum (CASS) embedding scheme for the Gaussian distributed host signal. However, in practice, the discrete cosine transform (DCT) coefficients of real images follow the Laplacian distribution. For practical application of CASS to real images in the DCT domain, this paper proposes a CASS data hiding scheme for the Laplacian distributed host image signal. To extract the hidden message bits, we derive an optimal decoder of the ASS scheme for the Laplacian distributed host signal. The bit-error ratio (BER) of ASS and proposed CASS schemes are analyzed in theory. Finally, Monte Carlo simulations and tests on real images are carried out to illustrate the decoding performance of the ASS and proposed CASS schemes. Compared with the traditional ASS scheme, the proposed CASS scheme maintains the simplicity of the decoder, significantly reduces the host effect in data hiding and improves the decoding performance remarkably. As an extension, we discuss the CASS scheme for the generalized Gaussian distribution (GGD) distributed host signal in brief. 相似文献
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The study examined a decision tree analysis using social big data to conduct the prediction model on types of risk factors related to cyberbullying in Korea. The study conducted an analysis of 103,212 buzzes that had noted causes of cyberbullying and data were collected from 227 online channels, such as news websites, blogs, online groups, social network services, and online bulletin boards. Using opinion-mining method and decision tree analysis, the types of cyberbullying were sorted using SPSS 25.0. The results indicated that the total rate of types of cyberbullying in Korea was 44%, which consisted of 32.3% victims, 6.4% perpetrators, and 5.3% bystanders. According to the results, the impulse factor was also the greatest influence on the prediction of the risk factors and the propensity for dominance factor was the second greatest factor predicting the types of risk factors. In particular, the impulse factor had the most significant effect on bystanders, and the propensity for dominance factor was also significant in influencing online perpetrators. It is necessary to develop a program to diminish the impulses that were initiated by bystanders as well as victims and perpetrators because many of those bystanders have tended to aggravate impulsive cyberbullying behaviors. 相似文献
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Lossy compression is inherently contradictory with information hiding and may result in unreliable retrieval of embedded message. For most of the existing data hiding algorithms, the process of dealing with the conflict and trade-off of invisibility, capacity and robustness is done in an experimental fashion. We have developed an image and video unified data-embedding technique. The algorithm is capable of accurately retrieving hidden data after the embedded signals are subjected to JPEG/MPEG compression as long as its compression degree is above the predefined one. Embedding strategy is to integrate data hiding into the JPEG/MPEG coding structures and to combine the adjustment factor of the strength and quantity of data hiding with the control parameter of lossy compression, according to the constraint of human visual system, the demand of hiding capacity and distortion impact of lossy compression. Experimental evaluation demonstrates that the proposed algorithm allows us to hide data invisibly in an accurate retrievable way with effective and flexible trade-off mechanism in the presence of lossy compression. In addition, the scheme is robust to some common attacks including low-pass filtering, noisy interference, frame dropping and transcoding. 相似文献
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In this paper, we propose a new reversible data hiding method in encrypted images. Due to spatial correlation, there is a large probability that the adjacent pixels of the image have small differences, which is especially obvious on the high four most significant bits (high nibbles) of the pixels. If the high nibble of each pixel is regarded as a 4-bit value, the differences between the high nibbles of the adjacent pixels are mostly concentrated in a small range. Based on this fact, Huffman coding was used to encode all the differences between the high nibbles of the adjacent pixels in order to compress the four most significant bit (MSB) planes efficiently and create a large-capacity room. After creating room, a stream cipher is used to encrypt the image, and the room is reserved in the encrypted image for data hiding without losing information. The experimental results showed that the proposed method can achieve a larger embedding rate and better visual quality of the marked decrypted image than other related methods. 相似文献
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This paper proposes a novel reversible data hiding method in encrypted images based on specific encryption process. In the proposed specific encryption algorithm, the stream cipher and prediction error are combined to vacate room for data embedding. After that, a permutation operation is performed on the encrypted image to improve the security. In the embedding process, we can embed a large amount of secret data in the encrypted image by pixel value expansion because most of the pixel values are less than 128 by the specific encryption process. At the receiver end, the encrypted image can be recovered from the marked encrypted image without knowing the secret data. Therefore, even if the recipient only has the encryption key, the original image will be perfectly recovered. If the recipient only has the data-hiding key, the secret data will be extracted. And if the recipient has both keys, the original image and the secret data are both available. The proposed method achieves a higher embedding capacity than that of methods based on vacating room after encryption. It does not require the image owner to perform reversible data hiding techniques on the original image, which is more convenient than methods based on reserving room before encryption. Experimental results demonstrate that the proposed method outperforms other state-of-the-art methods. 相似文献
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根据医院管理需求,把医院分散在各个业务系统的数据进行整合,建立了决策支持系统,对医院的日常管理提供决策依据,文章描述了系统建设的意义,并对系统设计部分和数据挖掘分析作了详尽的探讨。 相似文献