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一种红外弱小目标检测新方法 总被引:3,自引:2,他引:1
研究天空背景下红外运动弱小目标的检测。对红外序列图像进行累积后进行小波分析,再采用自适应门限处理,使用小波反变换将背景中低频分量和高斯噪声去除,再采用非线性滤波,最后再使用累积的方法找出目标,并得到目标航迹。实验结果表明,该方法能有效地检测定位运动红外弱小目标,并具有很强的抗噪声性能。 相似文献
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针对红外预警与跟踪系统中的实时弱小运动目标检测问题,在分析红外灰度图像的非平稳高斯特性的基础上,提出了一种基于高阶统计判据的检测算法。先用一个空域的白化去均值滤波器进行空间背景抑制,为下一步时域高阶统计判据建立一个不相关的高斯背景,根据三阶以上的高阶累积量对于高斯随机过程“盲”的原理,用高阶累积量作二元统计判据检测红外图像背景中的运动弱小目标。算法全面考虑了红外灰度图像和目标在时域与空域方面的特性,大大增强了目标信噪比。通过实际获取的大地背景目标红外数据检测表明,此算法能有效地从复杂背景中检测低信噪比运动小目标,虚警率少,抗噪声干扰能力强。算法易于硬件实现,能够有效地应用于红外搜索与跟踪系统的实时目标检测中。 相似文献
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红外弱小目标的分割与检测是地空导弹和航空导弹的关键技术。本文研究基于小波变换和目标运动特性的红外弱小目标的检测。在目标运动特性方面,主要采用了“与”管道进行目标的检测。大量试验表明,该算法具有很好的检测鲁棒性,且能够实时检测出红外图像中的弱小目标。 相似文献
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基于LWT和递归最小类内绝对差的红外小目标检测 总被引:1,自引:0,他引:1
针对存在背景干扰和噪声情况下的红外弱小目标检测问题,提出一种基于提升小波变换(LWT)和递归最小类内绝对差的检测方法.一方面先利用提升小波对原始图像进行去噪,再利用Top-hat算子抑制背景;另一方面先利用Top-hat算子抑制原始图像的背景,经提升小波去噪后,再进一步使用Top-hat算子;上述两方面得到的图像求和即为预处理图像.然后采用递归最小类内绝对差阈值选取方法分割预处理图像.针对红外小目标图像进行了大量实验,并与基于形态滤波及基于小波和形态学的红外小目标检测方法进行了比较.结果表明本文方法提高了信噪比,检测率分别提高15%和10%. 相似文献
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A novel two-stage wavelet packet feature approach for classification of rotated textured images is discussed. In the first stage, a set of sorted and dominant wavelet packet features is extracted from a texture image and a Mahalanobis distance classifier is employed to output N best classes. In the second stage, another set of wavelet packet features is extracted from the polarised form of the sample texture image and the most dominant wavelet packet features are selected and passed to the radial basis function (RBF) classifier with the N best classes to output the final matched class. Experimental results, based on a large sample data set of twenty distinct natural textures selected from the Brodatz album with different orientations, show that the proposed method outperforms the similar wavelet methods and the other rotation invariant texture classification schemes, and an overall accuracy rate of 91.4% was achieved 相似文献
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Wavelet packet image coding using space-frequency quantization 总被引:10,自引:0,他引:10
We extend our previous work on space-frequency quantization (SFQ) for image coding from wavelet transforms to the more general wavelet packet transforms. The resulting wavelet packet coder offers a universal transform coding framework within the constraints of filterbank structures by allowing joint transform and quantizer design without assuming a priori statistics of the input image. In other words, the new coder adaptively chooses the representation to suit the image and the quantization to suit the representation. Experimental results show that, for some image classes, our new coder gives excellent coding performance. 相似文献
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基于最优小波包基的自适应数字水印算法 总被引:5,自引:1,他引:4
提出了一种新的基于最优小波包基的数字水印算法,该算法充分利用了小波包的优点.对图像低频子带和纹理细节丰富的高频子带同时实施分解处理,并结合与人类视觉特性,采用自适应水印嵌入算法。实验证明该算法在保持嵌入水印图像具有良好视觉质量的同时,对常见的水印图像攻击方法具有较强的鲁棒性。 相似文献
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小波分析和小波包在图像消噪中的应用 总被引:1,自引:0,他引:1
小波包理论是在小波基础上发展起来的时频分析理论,在图像消噪中取得了较好的应用。文中介绍了小波分析和小波包的基本理论,分析了基于小波和小波包进行图像消噪的方法,利用MATLAB7对相同舍噪图像进行了计算机仿真,并对仿真结果进行了分析。实验表明,图像消噪效果与阈值的选取密切相关,小波包消噪后的效果比小波更好。 相似文献
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小波包是近年来的一个研究热点,在图像处理方面有着广泛的应用.数据压缩是伴随小波分析产生最早的应用领域.指纹自动识别系统因其本身的特殊性对指纹图像压缩提出了特殊的要求.为此,简要的介绍了小波包变换的基本原理,给出了基于小波包变换的指纹图像压缩方法. 相似文献
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提出一种基于小波包变换的嵌入式彩色图像压缩方法,利用彩色图像的三分量之间的相关性,结合小波包分解的思想和多级树集合分裂算法(SPIHT),对彩色图像进行压缩鳊码,对比分析表明该方法是可行的、有效的彩色图像压缩方法。 相似文献
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提出了一种基于推广的Shannon熵代价函数的快速自适应小波包算法。该算法在小波包分解过程中,先对图像数据的边界进行对称延拓,最后提出了一种与零树编码、自适应算术编码相结合的小波包图像压缩算法。 相似文献
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Synthetic aperture radar image compression using tree-structured edge-directed orthogonal wavelet packet transform 总被引:1,自引:0,他引:1
Jincai HuangAuthor VitaeGuangquan ChengAuthor Vitae Zhong LiuAuthor VitaeCheng ZhuAuthor Vitae Baoxin XiuAuthor Vitae 《AEUE-International Journal of Electronics and Communications》2012,66(3):195-203
Currently, wavelet-based coding algorithms are popular for synthetic aperture radar (SAR) image compression, which is very important for reducing the cost of data storage and transmission in relatively slow channels. However, standard wavelet transform is limited by spatial isotropy of its basis functions that is not completely adapted to represent image entities like edges or textures, which means wavelet-based coding algorithms are suboptimal to image compression. In this paper, a novel tree-structured edge-directed orthogonal wavelet packet transform is proposed for SAR image compression. Inspired by the intrinsic geometric structure of images, the new transform improves the performance of standard wavelet by filtering along the regular direction first and then along the orthogonal direction with directional lifting structure. The cost function of best basis selection is designed by textural and directional information for tree-structured edge-directed orthogonal wavelet packet transform. The new transform including speckle reduction can be used to construct SAR image coder with the embedded block coding with optimal truncation for transform coefficients, and arithmetic coding for additional information. The experimental results show that the proposed approach outperforms JPEG2000 and Fast wavelet packet (FWP), both visually and item of PSNR values. 相似文献
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In order to meet the requirements of medical research,diagnosis and treatment,a new algorithm for image fusion based on the wavelet packet transform in conjunction with both subjective and objective assessments is put forward in the paper.Compared to the wavelet transform,the wavelet packet transform is more intricate and effective for the medical image fusion.As indicated by the experimental results,parameters of the feedback system of the new algorithm are significantly superior to those of the wavelet tr... 相似文献