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1.
Wavelet transform has attracted attention because it is a very useful tool for signal analyzing. As a fundamental characteristic of an image, texture traits play an important role in the human vision system for recognition and interpretation of images. The paper presents an approach to implement texture-based image retrieval usingM-band wavelet transform. Firstly the traditional 2-band wavelet is extended toM-band wavelet transform. Then the wavelet moments are computed byM-band wavelet coefficients in the wavelet domain. The set of wavelet moments forms the feature vector related to the texture distribution of each wavelet images. The distances between the feature vectors describe the similarities of different images. The experimental result shows that theM-band wavelet moment features of the images are effective for image indexing. The retrieval method has lower computational complexity, yet it is capable of giving better retrieval performance for a given medical image database. Foundation item: Supported by the National Natural Science Foundation of China (69983005) Biography: Liao Ya-li(1979-), female, Master candidate, research direction: distributed network communication and multimedia information processing.  相似文献   

2.
构建一种基于三维混沌映射和位信息交换处理相结合的图像隐藏方法,将原始图像的高低Bit位进行交换,进而和Qi映射形成的3个维度上混沌序列截断矩阵进行异或处理,完成图像信息隐藏.实验结果表明:所提出的方法具有良好的视觉隐藏效果,隐藏后的图像在3个方向上的相关性非常低,并且对微小的密钥变化也非常敏感.  相似文献   

3.
无失真信息隐藏技术,可以使一个原始图像在经过藏入、取出秘密信息之后依然完整存储,为了进一步改进压缩域图像信息隐藏方法,文中提出了一种基于混合基底记法的无失真图像信息隐藏技术,主要做了以下工作:给出了应用的VQ编码、SMVQ编码的理论基础;完成了基于混合基底记法的信息隐藏的设计;应用6张512×512像素的灰度图片完成了实验结果验证。实验结果表明:新方法与传统的基于边缘匹配矢量量化编码方法相比,减少了秘密信息嵌入时间,提高了秘密信息嵌入容量。  相似文献   

4.
用于图像信息隐藏检测的位平面相关分析法   总被引:2,自引:0,他引:2  
从理论上研究了信息隐藏对空域数据统计特性的影响,利用位平面分割技术,分析了原图为伪图各位平面数据的统计特性。在此基础上,定义了一种位平面相关密度函数和相关几率分布图,提出了针对空域隐藏法的位平面分割相关分析法。  相似文献   

5.
Subliminal Channels in the NTRU and the Subliminal-Free Methods   总被引:1,自引:0,他引:1  
The construetion and destruction of subliminal channel are important problems in the information hiding. The subliminal channel can send secret information without notice. Two subliminal-free methods named weak (strong) subliminal-free on public-key cryptosystem (PKC) are proposed in this paper using the combinatorial method. The first method can only free the subliminal information with any minor probability and the second can free all. Moreover, the "traitor problem" which is same as the model of the subliminal channel in PKC is given. Two subliminal channels are embedded in N-th degree truncated polynomial ring (NTRU) cryptosystem, and their subliminal-free methods are also be obtained by the action of surveillant.  相似文献   

6.
An Effective Digital Watermarking Algorithm for Binary Text Image   总被引:2,自引:0,他引:2  
Aiming at the binary text image's characteristics of simple pixel, complex texture and bad immunity of information concealment, a digital watermarking embedment location choosing method has been put forward based upon compatible roughness set. The method divides binary text image into different equivalent classes. Equivalent classes are further divided into different subclasses according to each pixel's degree and texture changes between blocks. Through properties' combination, the embedment block and location which are fit for watermarking are found out. At last, different binary text images are chosen for emulation experiment. After being embedded, the image is compressed in JPIG-2. Gaussian noise, salt & pepper noise are added and cutting is employed to imitate the actual environment in which images may suffer from various attacks and interferences. The result shows that the detector has a sound testing effect under various conditions.  相似文献   

7.
鉴于图像的密文域可逆信息隐藏在安全云计算和隐私保护方面的重要作用,为了提高信息嵌入率,结合医学DICOM图像像素深度高、像素分布连续性高的特点,提出了一种结合两种压缩算法的密文域医学图像可逆信息隐藏算法。首先发送方对图像进行预处理,根据像素中高位比特连续为0的数量嵌入标记信息,腾出高位的冗余空间;然后用一种特殊设计的块加密算法进行加密,在保证明文信息不被泄露的同时保留了部分图像相关性;接着嵌入方根据标记信息,在对应位置嵌入额外信息;此外,为了进一步提高嵌入率,嵌入方还可以利用图像像素的相关性,在块内进行做差,并压缩实施信息嵌入。实验结果表明,该算法不仅具有较高的信息嵌入率,同时还有较好的安全性表现。  相似文献   

8.
采用基于支持向量机的图像信息隐藏技术,通过分析秘密图像的隐藏方法,得出了基于支持向量机的图像隐藏效果较好、图像隐藏的鲁棒性和不可见性都很好的结论.  相似文献   

9.
A geometrical transformations resistant digital image watermarking based on quantization is described. Taking advantage of the rotation, scale and translation invariants of discrete Fourier transform(DFT), each watermark bit is embedded into each homocentric circles around the zero frequency term in DFT domain by quantizing the magnitude vector of Fourier spectrum. The embedded sequence can he extracted by ““““““““majority principles““““““““ without restoring to the original unmarked image. The experimental results show that the watermark is invisible and robust to any combination of geometrical transformations or common image processing techniques.  相似文献   

10.
In this paper, algorithms of constructing wavelet filters based on genetic algorithm are studied with emphasis on how to construct the optimal wavelet filters used to compress a given image,due to efficient coding of the chromosome and the fitness function, and due to the global optimization algorithm, this method turns out to be perfect for the compression of the images. Foundation item: Supported by the Natural Science Foundation of Education of Hunan Province(21010506) Biography: Wen Gao-jin( 1978-), male, Master candidate, research direction: evolutionary computing.  相似文献   

11.
给出了一个基于复合混沌及LSB的图像加密和隐藏技术的方法,该方法首先利用Logistic映射和Tent映射进行复合产生混沌映射,用明文彩色图像的灰度信息来控制复合混沌的参数,产生的混沌序列对彩色图像进行加密,然后把加密图像用LSB算法嵌入到二个或多个载波图像中进行传输;实验和仿真结果表明:该方法具有隐藏效果好、密钥敏感性强、鲁棒性高等特点.  相似文献   

12.
A method used for recognition and understanding of airfield based on mathematical morphology is proposed in this paper. The new approach can be divided into three steps. First, to extract the typical geometric structure features of airfield, a segmentation method called recursive Otsu algorithm is employed on an airfield image. Second, thinning and shrinking algorithms are utilized to obtain the contour of airfield with single pixel and to remove diffused small particles. Finally, Radon transform is adopted to extract two typical and important components, primary and secondary runways of airfield exactly. At the same time, region growing algorithm is exploited to get the other components such as parking apron and garages. The experimental results demonstrate that the proposed method gives good performance. Foundation item: Supported by the National Defence Foundation of China (51401040603) Biography: WANG Zhi-cheng (1975-), male, Ph. D. candidate, research direction: medical images analysis, ATR.  相似文献   

13.
提出了一种新的调色板图像可逆信息隐藏方法. 首先, 将调色板的颜色重新排序, 使得相邻索引值对应的颜色尽可能相近. 然后, 对排序后的索引值直方图平移以嵌入秘密信息. 在嵌入过程中, 将对应的索引值改为与之相近的颜色索引值, 以有效缓解含密图像视觉质量的下降; 多次利用最大最小点, 大大提高了嵌入率. 实验结果证明, 本方法在保证可逆的同时显著提升了嵌入量, 并维持了较高质量的视觉效果; 同时, 对于索引值直方图无零点的情况同样适用, 克服了已有方法的局限性.  相似文献   

14.
A watermarking algorithm of binary images using adaptable matrix is presented. An adaptable matrix is designed to evaluate the smoothness and the connectivity of binary images. The watermark is embedded according to the adaptable matrix in this algorithm. In the proposed watermarking algorithm, each image block implements a XOR operation with the binary adaptable matrix, which has the same size with the image block, and in order to embed the watermark data, a multiplication operation are also implemented with the weight matrix. The experimental results show that proposed scheme has a good performance.  相似文献   

15.
针对现有的可逆信息隐藏算法在图像加密域应用场景下嵌入容量不高的问题,提出了一种基于最近邻像素预测的加密域可逆信息隐藏算法。充分利用自然图像的空间相关性,设计最近邻像素预测方法,计算预测误差,并进一步探究预测误差块分类规律,设计块内移位以及块重排方式,保留了块内相邻像素相关性。然后,通过动态标记块内误差区间以最大限度地空出冗余空间,达到提高嵌入容量的目的。选用5幅标准灰度图像及数据集BOSSbase、BOWS-2和UCID中的万余张灰度图像进行对比实验。结果表明:本文算法在安全性、可逆性和可分离性都满足的前提下,嵌入容量相比同类算法平均提升0.35~0.9 bpp(比特数)。  相似文献   

16.
Mouse Karyotype Obtained by Combining DAPI Staining with Image Analysis   总被引:3,自引:0,他引:3  
In this study, mitotic metaphase chromosomes in mouse were identified by a new chromosome fluorescence banding technique combining DAPI staining with image analysis. Clear 4', 6-diamidino-2-phenylindole (DAPI) multiple bands like (J-hands could be produced in mouse. The Meta- Morph software was then used to generate linescans of pixel intensity for the banded chromosomes from short arm to long arm. These linescans were sufficient not only to identify each individual chromosome but also analyze the physical sites of bands in chromosome. Based on the results, the clear and accurate karyotype of mouse metaphase chromosomes was established. The technique is therefore considered to he a new method for cytological studies of mouse.  相似文献   

17.
A vision based query interface annotation meth od is used to relate attributes and form elements in form based web query interfaces, this method can reach accuracy of 82%. And a user participation method is used to tune the result; user can answer "yes" or "no" for existing annotations, or manually annotate form elements. Mass feedback is added to the annotation algorithm to produce more accurate result. By this approach, query interface annotation can reach a perfect accuracy.  相似文献   

18.
为降低大数据量SAR图像对传输带宽和存储空间的要求,必须对SAR图像进行高效压缩.基于小波变换的传统SAR图像压缩方法只对低频子带进行分解处理,造成SAR图像处于中高频子带的重要纹理信息丢失.针对上述问题,提出一种基于小波变换的自适应SAR图像压缩算法.首先对图像进行小波软阈值消噪预处理,然后依据能量指标,进行子带重要性判定,对认定为重要的子带进行深一层次分解,分解完成后对所有子带进行恒定比特率条件下的最小误差量化,实现对图像的自适应压缩.仿真实验表明:该算法能很好地保护SAR图像的高频细节,提高了信噪比.  相似文献   

19.
首先将图像分解为8个位平面,选择前4个重要位平面,求出其灰度码表示,计算出每个灰度码位平面的欧拉数,组成欧拉向量;其次计算出每个灰度码位平面的信息熵,组成位平面熵向量;再把欧拉向量和位平面熵向量特征综合为一个新的图像特征,最后采用马氏距离计算图像间的相似度.实验结果表明本方法维数低,速度快,且避免了图像量化造成的误检,与比位平面熵算法和欧拉向量算法相比,检索效率高.  相似文献   

20.
JPEG文件隐形信息检测算法   总被引:1,自引:0,他引:1       下载免费PDF全文
隐秘信息分析的目的是正确分辨出文件中是否带有隐藏的信息.自然图像和含密图像的DCT系数经过差分之后,它们的直方图会呈现不同的规律,作者以此为特征向量,来检测JPEG图像是否带有隐藏信息.通过对原特征向量进行分析,提取了二次特征,用来估算在JPEG文件中大致所埋的信息量.实验结果表明,这一算法有效.  相似文献   

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