首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 421 毫秒
1.
This paper proposes a new watermarking approach using dynamic stochastic resonance (DSR) based tuning operation to extract the watermark logo from the watermarked image that has undergone different intentional and signal processing attacks. This method is intended to provide remedies from the shortcomings of the technique proposed by Lin et al. (2008), and invalidates the effect of intentional attacks recently designed by Meerwald et al. (2009). The algorithm incorporates three level image decomposition using lifting wavelet transform (LWT) and low-pass subband is utilized for data hiding purpose. Watermark bits are embedded into the blocks of non-overlapped wavelet coefficients of the cover image by quantizing the two maximum coefficients of the corresponding block. In watermark extraction process, the DSR is applied by performing the tuning operation on coefficient blocks of attacked watermarked image. It is a parameter dependent approach that enhances the performance of watermark extraction, where the parameters of DSR inherently depend on the image properties such as standard deviation or variance. As far as security is concerned, the randomization of wavelet coefficients, blocks, and watermark bits helps the framework to be more secure. The proposed technique is also examined against multiple watermarking attack and successfully proves its authenticity and ownership. Comparison of the proposed technique with recent techniques shows remarkable improvement in terms of robustness and security against various intentional, signal processing, and geometrical attacks.  相似文献   

2.
魏雯 《大众科技》2011,(11):45-47
以静止图像为研究对象,文章提出了一种离散分数傅立叶变换(DFRFT)域的图像数字水印算法,该算法通过对载体图像进行某个级次的分数傅立叶变换,将加密水印嵌入到载体图像的分数傅立叶谱中,从而得到含水印的图像。实验结果表明,该算法实现了水印图像的不可见性,同时对常见的图像攻击具有较好的鲁棒性。  相似文献   

3.
利用二维混沌流加密技术加密有意义的二进制图像,获得水印数据,以提高视频水印的安全性。水印嵌入过程中,水印被嵌入到随机选择的视频帧的离散余弦变换系数里。在鲁棒性和帧平均攻击实验后,大部分水印可以通过水印检测提取算法进行提取和识别。实验结果表明,这种视频水印方法具有一定的安全性、隐蔽性和鲁棒性。  相似文献   

4.
提出了一种新的基于视频压缩编码的动态图像水印方案。在嵌入水印时,充分考虑动态图像压缩编码的特性,对帧内编码帧(I帧),将水印信息嵌入到DCT低频系数中;而对帧间编码帧(P,B帧),结合动态补偿/离散余弦变换(MC/DCT)混介编码,把水印信息嵌入到运动补偿后的残差图像的自流成分中。同时,在水印嵌入时,采用扩频技术与多维水印相结合的方法,并通过相关检测的方法判断水印的存在。由于水印的检测是对视频码流直接实施的,不需要对压缩数据进行完全解码,从而大大降低了计算量,提高了视频数据水印的适用性。  相似文献   

5.
提出一种符合Kerckhoff原则的DCT域数字水印算法.该算法在嵌入水印前对水印进行Arnold变化,并通过密钥向量嵌入水印图像,大大提高了水印的鲁棒性和安全性.对比实验表明,该方案对高斯低通滤波、添加白噪声、JPEG压缩、图像剪切等攻击手段有较好的鲁棒性,并具有较高的安全性.  相似文献   

6.
Contourlet变换是一种基于图像的几何性变换,通过各向异性实现了图像的多尺度多方向性分解,它能够有效地表示图像中的轮廓和纹理。利用这些特性,提出了基于Contourlet域的盲水印算法。实验证明,该算法很好地协调了透明性与鲁棒性;并且实现了盲检测。  相似文献   

7.
This paper presents a new robust multiplicative watermark detector. Due to the strong robustness against various attacks, polar harmonic Fourier moment (PHFM) magnitudes are used as the employed watermark carrier. The distribution of PHFM magnitudes is highly non-Gaussian and can be properly modeled by a heavy-tailed probability density function (PDF). In this paper, we proved that Weibull distribution can suitably fit the distribution of PHFM magnitudes, and based on this, we presented a statistics-based watermark decoder by using the Weibull as a prior for the PHFM magnitudes. In watermark embedding, a multiplicative manner was used to embed watermark information in PHFM magnitudes of the highest entropy blocks to achieve better robustness and imperceptibility. In watermark detection, we developed a Weibull distribution-based statistical watermark decoder, which uses the maximum likelihood (ML) decision rule. Compared with Bessel K form (BKF), Cauchy, and generalized Gaussian (GG)-based decoders, the Weibull-based decoder demonstrates stronger robustness. In addition, the proposed watermark decoder is more robust against geometrical and common image processing attacks than existing statistical watermark decoders.  相似文献   

8.
把分形维数理论应用到数字水印中,提出了基于Chebysher混沌置乱和分形维数的自适应数字图像水印算法。首先将载体图像分块,计算每个小块的分形维数。然后将载体图像进行分块DCT变换,使用改进的邻域平均法,将经过混沌置乱后的水印信息嵌入到图像的DCT域中,并根据该小块的分形维数调节嵌入强度,实现了水印信息的自适应嵌入。提取水印时,实现了完全盲提取。MATLAB仿真结果表明,该算法具有较好的不可见性,对常见的图像处理攻击具有较好的鲁棒性。  相似文献   

9.
分析了一种小波域数字水印算法,利用人类视觉模型对算法进行了改进。选取一幅有实际意义的二值图像作为水印,在对原始图像进行多级小波分解后,通过修改中频系数来进行水印嵌入。实验证明嵌入水印后的图像具有更好的隐蔽性,并且对JPEG压缩、图像添加高斯噪声、中值滤波等图像处理操作具有很强的鲁棒性。  相似文献   

10.
提出了一种基于混沌的DCT域盲数字水印算法。本算法选用了有意义的二值图像作为水印,采用复合离散混沌动力系统产生的混沌序列对水印进行加密处理,在检测算法中不需要原始图像从而实现了盲提取,最后对仿真实验结果作出分析,证明此方案的可行性,攻击实验结果表明此方案的健壮性。  相似文献   

11.
本文提出了一种将彩色数字水印嵌入到彩色载体图像的新算法,利用改进的Patchwork方法将一级小波分解的水印图像的低频部分分别四次嵌入到经过离散余弦变换和离散小波变换后的载体图像的RGB分量中,提取的时候,将四次嵌入的低频分量取出并求平均值,用来作为水印的最终低频分量。经过实验验证,该算法对很多攻击具有很好的鲁棒性。  相似文献   

12.
Aiming at the problem that watermark information is easy to be lost in two-dimensional text image watermarking, a three-dimensional text image watermarking model is proposed based on multilayer overlapping of extracted two-dimensional information, and a specific method is accordingly realized by means of embedding, extracting and overlapping of multiple watermarks in sequence. We discuss the influence of the sequence order, positional distancing and color difference of the extracted multiple two-dimensional information on displaying a three-dimensional text watermark image. In addition, considering the crucial evaluation indices of the invisibility and robustness for the watermarking algorithm, the selection method for superior embedding regions of multiple watermarks is also constructed to enhance the robust performance of watermarks under the premise of effective invisibility. Moreover, we embed the multiple two-dimensional information into the host image by using the undecimated dual-tree complex wavelet transforms - bidiagonal singular value decomposition algorithm. In this way, the extracted multiple two-dimensional information is automatically overlapped to generate the three-dimensional text watermarking according to the optimal matching parameters. We use standard image processing data set to carry out experiments, the results show that the peak signal to noise ratio before and after embedded watermarks is higher than 39 dB, and the peak signal to noise ratio between the original watermarks and the extracted watermarks is more than 37 dB, which is superior to the current reported watermark model. Therefore, it is suggested that the proposed model shows good invisibility and robustness and can reduce the loss of watermark during transmission and attack as much as possible.  相似文献   

13.
一种基于二维离散小波变换的视频水印嵌入和盲提取算法   总被引:1,自引:0,他引:1  
白林雪  宗良 《中国科技信息》2011,(10):99-99,104
视频数字水印技术是当前水印研究中的一个热点。本文提出一种视频数字水印新算法,算法首先使用混沌序列对待嵌入水印信号进行混沌调制,然后对视频数据流中每帧图像进行2D-DWT后的低频小波系数进行操作,根据奇偶量化的特性,将水印信息嵌入到小波变换后的视频流中。所提出的水印算法简单、有效,实现了水印的盲提取,与嵌入水印前的原视频图像相比,嵌入水印后的视频图像信噪比损失很小。  相似文献   

14.
通过对基于混沌的DCT域数字水印技术在图像生成、水印嵌入、水印提取以及对水印攻击实验的结果分析中可以看出,此技术满足信息时代信息化所要求的数字图像信息隐藏的需要。  相似文献   

15.
基于块奇异值分解的水印算法研究   总被引:8,自引:0,他引:8  
奇异值分解是一种特殊的矩阵变换,并具有良好的性质。本文充分利用奇异值分解的特性,提出了一种新的基于块奇异值分解的量化水印算法和一种新的基于块奇异值分解的扩频水印算法。这两个算法都是通过对各个数据块的最大奇异值进行修改来嵌入水印,都可以根据待嵌入的水印信息量来调整分块的大小,算法的复杂度较低。其中的量化水印算法是含边信息的嵌入方法,可以实现盲检测。实验结果证明,基于块奇异值分解的水印算法对常规的图像处理攻击具有很好的鲁棒性,尤其是其中的量化水印算法。  相似文献   

16.
扩展频水印技术是一种鲁棒的水印算法 .如何提高扩频水印算法的鲁棒性是当前一大研究热点 .充分利用图象的像素与其周围像素之间的差值的统计特性 ,利用差调制的方法嵌入水印信息 ,从而降低了原始图象对该水印算法鲁棒性的影响 ,来提高水印算法的鲁棒性 .理论分析表明 ,该算法可以同时获得较小的误警和误拒概率 ,从而表明该算法有较好的性能 .实验结果表明 ,该算法可以鲁棒地抵抗常用的攻击 ,如JPEG压缩、中值滤波、加噪声和图象大小调整 .  相似文献   

17.
In this paper, a new homomorphic image watermarking method implementing the Singular Value Decomposition (SVD) algorithm is presented. The idea of the proposed method is based on embedding the watermark with the SVD algorithm in the reflectance component after applying the homomorphic transform. The reflectance component contains most of the image features but with low energy, and hence watermarks embedded in this component will be invisible. A block-by-block implementation of the proposed method is also introduced. The watermark embedding on a block-by-block basis makes the watermark more robust to attacks. A comparison study between the proposed method and the traditional SVD watermarking method is presented in the presence of attacks. The proposed method is more robust to various attacks. The embedding of chaotic encrypted watermarks is also investigated in this paper to increase the level of security.  相似文献   

18.
针对彩色数字图像的版权保护问题,提出了基于奇异值分解和离散的小波变换的彩色图像数字水印算法。算法将CIE-RGB色彩模式下的彩色图像转换到CIE-LAB色彩模式,然后将置乱后的水印嵌入到LAB色彩空间的L分量分块的小波分解低频系数的奇异值中。实验证明,该算法能够抵抗剪贴、拼贴、高斯噪声、JPEG压缩缩放、旋转等常用的图像处理的攻击,并且具有良好的不可见性和安全性。  相似文献   

19.
本文针对数字水印的抗攻击性问题,提出了一种新的基于置乱和奇异值分解的算法.算法首先将水印和载体图像同时进行置乱加密,再将置乱后的图像进行分块,然后对每块进行量化奇异值分解,在特征域嵌入水印.将双置乱技术引入分块量化奇异值分解方法中,进一步提高了奇异值分解算法的鲁棒性.其中,采用分块和置化特征矩阵的方法不用计算整个图像的SVD,大大缩短了水印嵌入和提取的时间.  相似文献   

20.
计云倩 《情报探索》2014,(5):112-115
介绍了数字图书馆和数字水印技术,就数字水印技术用于解决数字图书的图像版权保护问题进行了探讨,提出了一种用于图像认证的半易损数字水印算法。实验结果表明,该算法计算简单、有很好的抗JPEG压缩性能、对篡改的定位很精确。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号