共查询到20条相似文献,搜索用时 62 毫秒
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一种有效的红外图像中人造目标分割方法 总被引:1,自引:1,他引:0
提出一种红外图像单阈值分割方法。为了减少计算量,结合先验信息选择包含待分割目标的感兴趣区域,利用Bezier曲线法平滑感兴趣区域直方图的噪声;对平滑后的感兴趣区域的直方图求解其曲率曲线,用曲率曲线的波峰所对应的灰度值作为初始分割阈值;基于先验信息从初始分割阈值中确定最佳分割阈值并进行初步分割。为了弥补单纯利用阈值法分割的缺陷,结合上述分割结果和目标的边缘信息得到封闭性良好的完整目标的二值图像。实验结果表明,提出的方法能快速有效地将红外目标从复杂的背景中分割出来,算法的计算复杂度为O(MN)。 相似文献
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介绍了常用的图像分割方法及其优缺点和金相图像分析中的图像分割方法。针对金相图像分割中存在的问题,提出了两步分割的图像分割方法。这种方法是先用阈值分割法把目标从背景中分割开来,然后采用数学形态学、打孔、找凹点和连分割线的方法进行粘连分割。与已有的金相图像分割方法相比,这种方法具有较强的强健性、自适应性和非监督性。 相似文献
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一种改进的势函数聚类多阈值图像分割算法 总被引:6,自引:0,他引:6
针对基于势函数聚类的多阈值图像分割算法的不足,定义了伪势的概念,并在原算法基础上提出了一种改进的图像分割算法。由伪势概念确定了伪势合并的判别方法,按照此方法,当相邻的两个峰之间的距离小于所定义的自适应模糊伪势因子时,则应该进行伪势合并。改进后的算法在计算剩余势函数时判断是否存在伪势,然后在势划分函数组的确定过程中相应地进行伪势合并计算。利用多幅图像进行了多阈值分割的仿真试验,结果表明,改进的基于势函数的多阈值图像分割算法具有更好的鲁棒性和分割效果。 相似文献
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针对红外图像的特点,提出了一种基于遗传算法的自动模糊分割红外车辆目标图像的方法.首先选取图像的感兴趣区域以加快运算速度;然后对感兴趣区域图像进行模糊增强,借助于二维OTSU方法对增强后的感兴趣区域进行阈值分割,为了加快分割算法的速度,先限定一个最佳阈值范围,再利用遗传算法在此阈值范围内自动搜索最佳分割阈值;为了弥补单独利用二维OTSU方法分割的不足,采用缩短模糊边缘宽度的方法来提取感兴趣区域红外车辆目标图像的边缘.最后把二维OTSU方法分割的图像与模糊边缘提取得到的边缘图像进行或运算后进行填充以得到最终的车辆目标分割图像.实验结果表明,对于红外车辆目标图像,一维OTSU和二维OTSU算法只是基本分割出了红外车辆目标的主体,而本文提出的自动模糊分割技术不仅准确分割出了红外车辆目标的主体,而且对于坦克的模糊炮塔亦得到了完整的分割. 相似文献
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改进的模糊阈值图像分割方法 总被引:5,自引:1,他引:4
提出了一种自适应的模糊阈值图像分割方法,通过预分割和直方图信息相结合的方法,解决了传统的模糊闽值图像分割法难以自动获取窗宽的困难;并针对模糊闽值图像分割方法不能适用于直方图呈单峰分布的图像的缺陷,提出了一个新的平滑迭代公式。该平滑迭代公式利用像素点的邻域信息使图像增强,再使用自适应的模糊阈值图像分割方法进行分割,可以拓宽模糊阈值图像分割方法的适用范围。实验结果表明,使用该方法的目标分割正确率达97.3%,显示了较高的分割精度和较强的鲁棒性。 相似文献
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A method is proposed for estimating the parameters of a mixture of exponential and Weibull distributions for which the accuracy of preliminary estimates obtained by graphical analysis is refined in accordance with the criterion of maximum likelihood. The efficiency of the proposed method is supported by the results of statistical modeling. 相似文献
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O'Brien RS 《Radiation protection dosimetry》2003,105(1-4):95-100
Australia has several uranium mines and a large number of mineral sand mines, with associated processing facilities. Exposures resulting from these mining and processing operations usually involve intakes of mixtures of radionuclides. This work describes the development of a suite of first order, linear compartment models, based on the ICRP Publication 66 respiratory tract model, and an analytical solution to the decay equations, for assessing the consequences of such intakes. The computer programs based on these models directly compute excretion, organ retention and organ and whole-body doses for intakes of either single radionuclides or any mixture of radionuclides belonging to the same radioactive decay chain. The intake can be via inhalation, ingestion or injection, and can be acute, chronic or of limited duration. The starting concentration and degree of secular (dis)equilibrium can be specified for each radionuclide. No assumptions need to be made about the relative magnitudes of the radioactive half-lives of the different nuclides. 相似文献
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本文根据多年的实践检定经验 ,参照JJF1 0 59- 1 999《测量不确定度评定与表示》以及《测量不确定度表达 1 0讲》 ,对卧式金属罐容量的测量结果不确定度进行了评定。 相似文献
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Liebert A Wabnitz H Grosenick D Möller M Macdonald R Rinneberg H 《Applied optics》2003,42(28):5785-5792
A novel method for the determination of the optical properties of tissue from time-domain measurements is presented. The data analysis is based on the evaluation of the first moment and the second centralized moment, i.e., the mean time of flight and the variance of the measured distribution of times of flight (DTOF) of photons injected by short (picosecond) laser pulses. Analytical expressions are derived for calculation of absorption and of reduced scattering coefficients from these moments by application of diffusion theory for infinite and semi-infinite homogeneous media. The proposed method was tested on experimental data obtained with phantoms, and results for absorption and reduced scattering coefficients obtained by the proposed method are compared with those obtained by fitting of the same data with analytical solutions of the diffusion equation. Furthermore, the accuracy of the moment analysis was investigated for a range of integration limits of the DTOF. The moment analysis may serve as a comparatively fast method for evaluating optical properties with sufficient accuracy and can be used, e.g., for on-line monitoring of optical properties of biological tissue. 相似文献
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V. Ya. Fateev 《Measurement Techniques》2011,54(7):774-780
Different constructions of the sensing elements of radio-frequency level sensors based on sections of long lines are numerically
investigated by means of the Matlab program for the purpose of minimizing the measurement error caused by the nonlinearity
of the output characteristic. It is shown that the nonlinearity is lowest for U-shaped designs. The nonlinearity factor KN
may be regulated by varying the capacitance of a correcting capacitor connected to the input of the sensing element and (or)
the length of one of the sections of the long line. In selecting an optimal capacitance of the correcting capacitor KN ≤ 0.15%
for control media with dielectric permittivity in the range 2.2–30. 相似文献