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红外图像中小目标检测研究 总被引:5,自引:1,他引:4
在获得的红外序列图像中,检测和跟踪微弱小目标一直是研究的重点。本文对小目标检测系统的背景抑制和目标检测算法和方案进行了调研。采用背景抑制算法以获得更高的信噪比,利用NP准则对图像进行分割,然后用识别算法对目标进行跟踪和识别。计算结果显示,抑制杂波后,采用序贯图像检测能够很好地增加探测概率。 相似文献
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头肩序列图像是可视电话、会议电视等视频业务中常见的一种图像模式.本文将SPIHT算法与人脸检测算法相结合,提出一种嵌入式的头肩图像编码方法.首先采用人脸检测技术确定头肩图像中的人脸区域;然后产生人脸区的掩膜,并对LL子带中人脸区掩膜内的小波系数进行定标,以保证人脸区的小波系数能优先编码;最后采用SPIHT算法对人脸区和背景区进行编码.实验结果表明,与原来的SPIHT方法相比,这种方法可以保证人脸区域的重建质量好于背景区的重建图像.同时压缩后的码流仍然具有嵌入的特性,支持渐进传输. 相似文献
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为了提高扫描成像系统对于点目标的探测性能,提出了时-空过采样点目标探测体制,并对其进行了目标检测性能分析。首先,分析了单采样体制在点目标探测中易存在跨像元导致的目标能量分散问题,以及探测器随机高强度噪声及空间质子流尖峰信号导致的虚警问题;然后,提出了用于点目标扫描探测的时-空过采样体制。最后,基于图像信噪比对相同光学系统下单采样和时-空过采样系统的目标检测性能进行了比较分析。分析结果表明,通过过采样方式能够实现目标能量集中到一个像元,保证了图像信噪比需求。通过高分辨率融合使得目标尺度大于噪声及尖峰的尺度,目标尺度最大扩展至3?3像元,基于目标空间相关的处理可以有效降低虚警,提升系统检测性能。 相似文献
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传统的采样系统对点目标的能量收集能力差,图像信噪比低,像斑面积小。为了克服传统采样的缺点,在对弱点目标进行探测时可以采用双向过采样技术。建立了点目标采样系统的数学模型,分析了双向过采样系统对点目标的检测性能。通过点目标采样系统的数学模型,得到了双向过采样系统点目标像斑分布均匀、灰度梯度小、有一定的面积的特点。从而设计出针对双向过采样系统的点目标检出方法。采样模型得到的像斑能量分布表明,双向过采样系统对点目标的能量收集能力强,点目标像斑面积大,信噪比稳定,采样系统对点目标的空间相对位置有很强的适应能力。仿真分析表明,目标检出方法能够有效提高点目标图像的信噪比。 相似文献
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《IEEE transactions on information theory / Professional Technical Group on Information Theory》1985,31(1):69-80
Some schemes for detecting moving point targets against structured backgrounds from observations on the output of an imaging system are investigated. When the velocity of the target and the background image are considered as known, it is shown that the uniformly most powerful detector, invariant with respect to image intensity variations, consists of specific spatial-temporal differencing schemes. This places such schemes on a rigorous foundation. 相似文献
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介绍了基于可编程片上系统SOPC技术的图像处理系统的软硬件设计,系统采用FPGA作为视频信号采集控制模块,利用FPGA内建NIOSⅡ软核微控制器作为图像处理单元。针对天空背景下红外弱小目标,提出了一种基于形态学和仿生学相结合的图像预处理算法,该算法在基于数学形态学滤波的基础上利用人眼固视微动辨别信息的原理对图像进行背景抑制和目标增强;采用自适应阈值分割法确定目标。硬件实验结果表明系统实时性好,图像处理效果良好,目标检测率高,验证了预处理算法的有效性和实时性。 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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Chiang S.-S. Chang C.-I. Ginsberg I.W. 《Geoscience and Remote Sensing, IEEE Transactions on》2001,39(7):1380-1391
The authors present a projection pursuit (PP) approach to target detection. Unlike most of developed target detection algorithms that require statistical models such as linear mixture, the proposed PP is to project a high dimensional data set into a low dimensional data space while retaining desired information of interest. It utilizes a projection index to explore projections of interestingness. For target detection applications in hyperspectral imagery, an interesting structure of an image scene is the one caused by man-made targets in a large unknown background. Such targets can be viewed as anomalies in an image scene due to the fact that their size is relatively small compared to their background surroundings. As a result, detecting small targets in an unknown image scene is reduced to finding the outliers of background distributions. It is known that “skewness,” is defined by normalized third moment of the sample distribution, measures the asymmetry of the distribution and “kurtosis” is defined by normalized fourth moment of the sample distribution measures the flatness of the distribution. They both are susceptible to outliers. So, using skewness and kurtosis as a base to design a projection index may be effective for target detection. In order to find an optimal projection index, an evolutionary algorithm is also developed to avoid trapping local optima. The hyperspectral image experiments show that the proposed PP method provides an effective means for target detection 相似文献
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介绍了红外成像系统对点目标的探测跟踪作用距离估算方法,用热成像分析系统研究点目标在像素上的扩散规律,提出用热成系统探测点目标时,扩散因素对作用距离的影响。 相似文献
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被动毫米波金属目标图像识别并自动统计出目标个数是军事自动化技术的一个重要环节。给出了毫米波探测目标的简要原理,针对目前有关毫米波被动探测并自动计算出金属目标个数方法的欠缺,首次尝试并给出了被动毫米波金属目标图像处理方案及详细处理过程,在毫米波图像分辨率低的条件下,将图像二值化,用数学形态学对图像进行处理,用Canny算子进行边缘检测并提取图像的边缘轮廓,再用Visual C++6.0开发工具,实现二值图像连通域像素标记算法,搭建起金属目标个数的计数系统。给出系统的定量分析,并与面积法计算目标个数做了对比。经分析,系统具有准确性,且响应时间短。 相似文献
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Target tracking is an important branch of computer vision, which includes three stages: image sequence optimizing, target expressing and target detecting. The target detecting stage is an important factor that influences the tracking performance. Therefore, how to obtain a more accurate and robust target detecting method becomes an urgent problem. Online sequential extreme learning machine (OSELM) is a kind of online learning method based on extreme learning machine. OSELM completes incremental learning by combining with the existed model when dynamic training samples are arriving. That OSELM has advantages including fast-speed and incremental learning suggests that is suitable for target detecting. Nevertheless, the target detecting process is different from the traditional classification for two causes: (1) target detecting is the dynamic process in that the position and rotation of the target are changing with time, and therefore the original OSELM method fails to obtain the most optimal target object from classified samples, (2) the tracking result frame depends on the previous frame, thus if the noisy sample is used as the target object, it would generates an impact to the tracking performance. To alleviate above-mentioned problems, this paper proposes an interesting and efficient target tracking method based on OSELM. In this method, we obtain the appropriate target object by judging the position relationship between each classified sample and the classification boundary. Moreover, we develop a kind of method that is similar to clustering to avoid tracking drift from noisy samples. The new target tracking method improves the performance remarkably, and eliminates the tracking drift from noisy samples. The proposed method is validated on six kinds of challenging image sequences. 相似文献