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《现代制造工程》2018,(12)
为了提高机器视觉系统的图像分割精度,提出了一种以小波变换为分类特征的多神经网络(Multi-Neural Network,MNN)图像分割算法,该算法包括小波特征提取、MNN区域划分和MNN分类3个阶段。其中,小波特征提取根据小波变换的各层图像扩展得到分类特征;MNN区域划分将初分割边界附近区域分为训练样本区域和待分类区域(待分区域),并用多边形拟合算法将待分区域划分为多个局部待分区域;MNN分类将每个局部待分区域的像素用区域内的神经网络分类器进行分类,确定目标像素和背景像素,将目标像素合并后再进行一定的后处理即可得到分割结果。以轴承表面缺陷检测系统采集的轴承缺陷图像为对象,对MNN算法和阈值分割算法进行了对比试验,结果显示MNN算法的像素数量误差(Pixel Error,PE)相比阈值分割算法降低了75%,分割精度显著提高。 相似文献
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高铁钢轨表面图像具有光照变化、反射不均、特征少等特点,使得缺陷自动检测极为困难。为了在高速运动过程中,从复杂的钢轨表面图像中分割出缺陷,根据钢轨表面图像具有沿钢轨方向像素值基本不变的特征,建立钢轨表面图像背景模型,提出了基于背景差分的钢轨表面缺陷检测算法,主要包括钢轨区域提取、背景建模差分、阈值分割和图像滤波4个步骤,其主要特点是将视频监控中的背景差分法推广到缺陷图像分割领域,同时借助自适应阈值分割和滤波技术,在一定程度上,解决了铁轨表面缺陷分割过程中图像光照变化、反射不均、特征少等不利因素的影响。实验仿真和现场测试结果均表明,该方法对块状缺陷能很好地识别,召回率和准确率分别达96%和80.1%。 相似文献
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给出了一种基于图像灰度分布统计特征期望值为阈值的二值化方法.并在此基础上运用数学形态学方法进行图像目标定位分割。应用于有噪声的车牌图像二值化和分割、实验表明本文提出的二值化算法的计算复杂度.执行时间、二值化效果以及适用范围等方面均有较佳表现.形态学分割算法定位效果好、分割精度高。 相似文献
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Hartman-Shack传感器图像阈值的选取对质心探测精度有较大的影响,而质心探测精度将直接影响探测波前的复原。通过介绍几种阈值分割的原理和方法,在比较多幅基点图像质心探测精度的基础上,提出了基于灰度拉伸的大津法是阈值分割的较好方法。 相似文献
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为克服图像分割中图像目标与背景之间存在的对比度低、亮度分布不均匀以及在搜索最佳阈值的过程中有可能陷入局部最优解等问题,运用混沌和声搜索算法搜寻最佳阈值,将模糊Renyi熵与混沌和声搜索算法相结合进行图像分割。实验结果显示了该方法对红外人体图像以及单峰、双峰、多峰图像都有较好的分割效果。 相似文献
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由于海参养殖的水下环境相对复杂,导致水下拍摄得到的图像容易受到水源浑浊度、光照折射或水流速度等环境因素影响,造成图像质量低,更有海草、水下生物、人类垃圾等背景因素干扰,给图像中海参的检测造成了很大的困难。结合水下海参图像的实际情况,首先对采集到的图像进行灰度值范围调整使图像更加明亮,突出图像中的重要信息;选择高斯高通滤波器使图像得到锐化处理去除图像的低频部分,突出图像边缘;之后采用全局阈值分割方法将目标对象和背景较为明显的区分出来。通过上述方法实现海参图像的增强、分割处理,为水下海参图像的检测识别提供一种有效的图像处理方法。 相似文献
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A novel segmentation approach for noisy medical images using Intuitionistic fuzzy divergence with neighbourhood‐based membership function
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A. JATI G. SINGH S. KOLEY A. KONAR A.K. RAY C. CHAKRABORTY 《Journal of microscopy》2015,257(3):187-200
Medical image segmentation demands higher segmentation accuracy especially when the images are affected by noise. This paper proposes a novel technique to segment medical images efficiently using an intuitionistic fuzzy divergence–based thresholding. A neighbourhood‐based membership function is defined here. The intuitionistic fuzzy divergence–based image thresholding technique using the neighbourhood‐based membership functions yield lesser degradation of segmentation performance in noisy environment. Its ability in handling noisy images has been validated. The algorithm is independent of any parameter selection. Moreover, it provides robustness to both additive and multiplicative noise. The proposed scheme has been applied on three types of medical image datasets in order to establish its novelty and generality. The performance of the proposed algorithm has been compared with other standard algorithms viz. Otsu's method, fuzzy C‐means clustering, and fuzzy divergence–based thresholding with respect to (1) noise‐free images and (2) ground truth images labelled by experts/clinicians. Experiments show that the proposed methodology is effective, more accurate and efficient for segmenting noisy images. 相似文献
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图像分割是图像处理中的一个重要问题,全局阈值法和局部阈值法是图像分割中广泛采用的两类方法。全局阈值法效率高,但是对局部信息不敏感;局部阈值法对局部信息保存较好,但是计算效率不高。针对这一问题,该文提出一种基于分块的图像分割算法。首先将图像分块,然后,每块内采用最大类间方差法计算阈值,最后,块与块之间采用线性插值的方式平滑分割图像。实验表明,该文提出的算法和全局阈值法相比能较好地保存局部信息,和局部阈值法相比有更高的运行效率,在实际中推荐使用。 相似文献
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Grain‐oriented segmentation of images of porous structures using ray casting and curvature energy minimization
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We segment an image of a porous structure by successively identifying individual grains, using a process that requires no manual initialization. Adaptive thresholding is used to extract an incomplete edge map from the image. Then, seed points are created on a rectangular grid. Rays are cast from each point to identify the local grain. The grain with the best shape is selected by energy minimization, and the grain is used to update the edge map. This is repeated until all the grains have been recognized. Tests on scanning electron microscope images of titanium oxide and aluminium oxide show that their process achieves better results than five other contour detection techniques. 相似文献
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为提高红外图像弱小目标检测的准确率和实时性,在分析用于红外图像增强的分形参数K相关的多尺度分形特征(MFFK)基础上,提出了一种基于改进多尺度分形特征(IMFFK)的红外图像弱小目标检测算法。首先,将基于地毯覆盖法的分形维数计算公式代入MFFK计算公式,提出了一种改进多尺度分形特征(IMFFK)用于图像增强。其次,对IMFFK特征计算进行简化,采用自适应阈值分割得到感兴趣目标区域,提出了一种具有较高计算效率的红外图像弱小目标检测算法。最后,通过仿真图像分析了主要参数对图像增强和算法耗时的影响,采用红外真实图像进行了算法检测性能测试,并与当前基于局部对比度测度的目标检测算法进行了对比。实验结果表明,提出的算法虽然在一些检测场景具有较多虚警,但能同时适用于弱小目标和较大目标检测,且无论目标为亮目标或暗目标。提出算法对于低分辨率红外图像(320×240)检测接近30 frame/s。提出算法具有较强的适用性,能够检测出红外图像中具有较高局部对比度的目标。 相似文献
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We present an approach for automatic threshold segmentation of greyscale images. The procedure is inspired by a reinterpretation of the strategy observed in human operators when adjusting thresholds manually and interactively by means of ‘slider’ controls. The approach translates into two methods. The first one is suitable for single or multiple global thresholds to be applied globally to images and consists of searching for a threshold value that generates a phase whose boundary coincides with the largest gradients in the original image. The second method is a variation, implemented to operate on the discrete connected components of the thresholded phase (i.e. the binary regions) independently. Consequently, this becomes an adaptive local threshold procedure, which operates relative to regions, rather than to local image subsets as is the case in most local thresholding methods previously published. Adding constraints for specifying certain classes of expected objects in the images can improve the output of the method over the traditional ‘segmenting first, then classify’ approach. 相似文献
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Haiyong Zheng Hongmiao Zhao Xue Sun Huihui Gao Guangrong Ji 《Microscopy research and technique》2014,77(9):684-690
A novel image processing model Grayscale Surface Direction Angle Model (GSDAM) is presented and the algorithm based on GSDAM is developed to segment setae from Chaetoceros microscopic images. The proposed model combines the setae characteristics of the microscopic images with the spatial analysis of image grayscale surface to detect and segment the direction thin and long setae from the low contrast background as well as noise which may make the commonly used segmentation methods invalid. The experimental results show that our algorithm based on GSDAM outperforms the boundary‐based and region‐based segmentation methods Canny edge detector, iterative threshold selection, Otsu's thresholding, minimum error thresholding, K‐means clustering, and marker‐controlled watershed on the setae segmentation more accurately and completely. Microsc. Res. Tech. 77:684–690, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
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基于二维对称Tsallis交叉熵的小目标图像阈值分割 总被引:2,自引:0,他引:2
现有的阈值分割方法应用于目标与背景面积相差悬殊的小目标图像时,几乎都失效.为此,提出了基于对称Tsallis交叉熵及背景与目标面积差的小目标图像阈值分割方法.对称Tsallis交叉熵准则能确保准确分割时目标和背景内部的灰度均匀,而背景与目标面积差可抑制均等分割的趋势,二者综合构成了更为合理的阈值选取准则函数.首先导出了一维阈值选取公式;然后经推广得到基于二维斜分对称Tsallis交叉熵及背景与目标面积差的阈值选取公式,给出了其快速递推算法及相应的简化方法.大量实验结果表明:与目前性能较优越的二维斜分Otsu、最大熵、非对称交叉熵阈值分割方法相比,所提出的方法在小目标图像分割效果上具有极为明显的优势. 相似文献
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A gradient image-segmentation method for analyzing fields of images containing several objects is developed. This method uses the dynamic thresholding and is applied to the analysis of video images of pendant and sessile drops for determining the interfacial tension of liquids and contact angles. 相似文献
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Yinggan Tang Xiumei Zhang Xiaoli Li Xinping Guan 《The International Journal of Advanced Manufacturing Technology》2009,43(5-6):431-439
X-ray-based inspection technique is well applied to identification and evaluation of internal defects in castings, such as cracks, porosities, and foreign inclusions. Combining X-ray inspection with digital image processing and automatic image assessment is now the preferred approach for the continuous inspection of castings. However, in practical application, the quality of the X-ray image is poor. Under the circumstances, many classical thresholding methods usually cannot obtain ideal segmentation results. In this paper, we propose an effective segmentation method for the detection of typical internal defects in castings derived for an X-ray inspection system. The proposed method takes advantage of the fuzzy set theory and bound histogram and presents fuzzy exponential entropy for object and background according to the fuzzy sets and gray-level distribution of the image. The ideal threshold is obtained by maximizing the fuzzy exponential entropy associated with the distribution of the object and background classes in the bound histogram. Experimental results indicate that the proposed method is a powerful method to analyze images derived from X-ray inspection for automatically detecting typical internal defects in castings. 相似文献