基于Gabor变换的木材表面缺陷图像分割方法

为了提高对木材表面缺陷图像分割的正确率,采用了环形Gabor滤波器将木材纹理图像变换到联合空间频率域,并在能量意义下定义了特征参数.根据多方向滤波结果形成缺陷图像的分割特征向量.结合模糊C均值聚类算法和数学形态学后处理操作提取出缺陷目标区域,分割正确率为98.29%.通过与基于灰度共生矩阵的分割方法进行比较实验,该方法平均分割精度比后者提高了4.22%,实验结果表明了该方法的可行性.     

基于嵌入式图像处理的仪表自动识别技术研究

针对远程抄表系统中的仪表读数识别问题,提出了一种有效的识别算法。依据仪表图像的特点,在均值滤波、形态学运算以及最大类间方差法对仪表图像预处理之后,利用轮廓检测以及连通域分割等方法对表盘区域和单个数字进行分割,并依据数字结构特征,对分割出的数字进行识别。将该算法移植到以S3C2440A为核心的ARM-Linux系统中进行测试,可以有效识别,获得了满意的效果。     

基于图像连通区域面积的成捆棒材自动计数方法

提出了一种基于图像连通区域面积的成捆棒材自动计数方法。该方法首先对获取的棒材图像进行灰度化、滤波和图像分割处理,然后对分割图像中的连通区域分类:小于基本面积的区域视为噪声区域,介于基本面积和阈值面积之间的区域视为一支棒材区域,大于阈值面积的区域表示多支棒材粘连区域。对于多支棒材粘连区域,采用区域面积除以标准面积得到棒材支数。最后将所有连通区域的棒材支数求和即可得到图像中全部棒材的支数。该方法应用于13幅成捆棒材图像计数实验时所得误差均小于3%。     

一种基于形态学操作的SAR图像道路检测方法研究

提出了一种基于形态学结构运算操作的SAR图像道路检测方法.该方法首先进行滤波去噪处理,经过实验对比分析得出各种滤波的优劣,再利用形态学操作对原始图像进行高低帽图像增强处理,运用线性生长和区域填充方法进行线性提取,然后利用边缘检测算法检测目标,利用连通域目标的面积和空间关系等特征去除少量误提道路特征,最后按照一定规则利用霍夫变换进行自动道路检测.实验表明,新方法可以取得很好的效果.     

基于多阈值融合的图像分割

提出了一种基于知识的多阈值融合图像分割新方法．首先利用一组多阈值分割结果建立连通域生长树．然后判断树叉对应的连通域合并是否合理，为此提出了连通体元、体元生命期、体元体积等概念，结合灰度均匀性定义出通用合并准则．最后将图像各位置的最佳连通域组合为最终图像分割结果．该算法充分利用了目标的灰度和空间属性，对灰度平稳和渐近变化的多目标图像分割非常有效．此外，该算法可以有效融合具体应用的先验知识，具有很高的智能性。     

基于背景重建的运动目标检测与阴影抑制

提出了一种静止摄像机条件下的运动目标检测和去除阴影的方法。该方法采用以图像亮度和能量大小为判断依据的分块背景重建方法来快速更新背景,并结合背景相减法,网格化连通域检测,形态学滤波等步骤来检测和提取运动目标,同时运用边缘检测获取阴影边缘信息,并结合形态学运算来去除阴影区域,恢复出完整物体目标。实验结果表明,该方法能够有效地检测出运动目标和抑制阴影。     

基于背景差分法的运动目标分割

运动目标分割在基于视频的运动目标检测与识别研究中发挥着重要作用。以图像差分法为基础,实现了一种复杂背景下快速分割运动目标的方法。通过中值滤波对原始图像进行预处理;运用改进的Surendra算法快速提取并更新背景图像;利用数学形态学运算对差分二值图像进行处理,进行运动区域的初始检测;将RGB图像转换到HSI域中进行适当的阴影去除,完成运动目标分割。实验结果表明该方法能够较为有效地分割出感兴趣区域(ROI)内的运动目标。     

基于Gabor滤波器的棉花杂质检测算法

棉花杂质检测方法对于提高织物质量和降低生产成本具有重要意义。针对工业环境中非均匀光照条件下的棉花图像设计基于Gabor滤波器的杂质检测算法,依据Otsu法和形态学滤波将图像分割为前景区、背景区和交界区,然后在图像前景和背景区域内分别使用Gabor滤波器提取图像的纹理特征。设计一种针对Gabor滤波输出的自适应阈值分割算法,结合形态学滤波和连通域分析检测出棉花中的杂质。实验结果表明,本文算法有效地消除了由于光照条件造成的干扰,可以精确地检测出棉花中常见的各种杂质。     

基于各向异性滤波和空间FCM的MRI图像分割方法

针对具复杂目标和边界模糊的MRI图像中多感兴趣区域的分割中分割MRI图像软组织难的问题, 提出了一种基于各向异性滤波和空间模糊C-均值聚类(SFCM)的MRI图像分割方法; 用新型各向异性滤波对图像进行预处理, 解决去噪平滑的同时弱化图像细节的问题; 用邻域空间信息设计空间函数, 改进传统FCM的目标函数; 用图像的空间信息实现图像各目标准确分类、有效解决孤立区域的正确归类问题, 进而使分割区域完整; 用直方图拟合曲线初始化分类数和初始聚类中心, 加快算法迭代到最优解, 进而减少运行时间。通过实验证实了各向异性滤波和空间FCM的MRI图像分割方法的综合应用显著提高了分割灰度重叠、目标不连续和目标边界模糊的MRI图像的分割效果。     

改进的基于连通域的版面分割方法

版面分割是版面分析的重要组成部分,经过大量的研究,如今已到了一个比较成熟的阶段。对基于连通域的版面分割算法进行了改进,能有效快速地分割较为复杂的版面图像,同时有效减少原有算法中阈值引起的分割错误的情况。先对文本图像进行单个字体的区域扩充,使后续的连通间距统计更为准确和方便,再通过连通间距的统计对图像进行模糊整合,进行文本图像的连通区域分割。实验结果表明,改进的基于连通域的算法分割版面准确,速度快,适用范围广,对于较为复杂的版面分割更具有优越性。     

Detecting changes in high-resolution satellite coastal imagery using an image object detection approach

This article presents a spatial contrast-enhanced image object-based change detection approach (SICA) to identify changed areas using shape differences between bi-temporal high-resolution satellite images. Each image was segmented and intrinsic image objects were extracted from their hierarchic candidates by the proposed image object detection approach (IODA). Then, the dominant image object (DIO) presentation was labelled from the results of optimal segmentation. Comparing the form and the distribution of bi-temporal DIOs by using the raster overlay function, ground objects were recognized as being spatially changed where the corresponding image objects were detected as merged or split into geometric shapes. The result of typical spectrum-based change detection between two images was enhanced by using changed spatial information of image objects. The result showed that the change detection accuracies of the pixels with both attribute and shape changes were improved from 84% to 94% for the strong attribute pixel, and from 36% to 81% for the weak attribute pixel in study area. The proposed approach worked well on high-resolution satellite coastal images.     

DOST: a distributed object segmentation tool

This paper presents a novel distributed object segmentation framework that allows one to extract potentially large coherent objects from digital images. The proposed approach requires minimum user supervision and permits to segment the objects accurately. It works in three steps starting with the user input in form of few mouse clicks on the target object. First, based on user input, the statistical characteristics of the target distributed object are modeled with Gaussian mixture model. This model serves as the primary segmentation of the object. In the second step, the segmentation result is refined by performing connected component analysis to reduce false positives. In the final step the resulting segmentation map is dilated to select the neighboring pixels that are potentially incorrectly classified; this allows us to recast the segmentation as a graph partitioning problem that can be solved using the well-known graph cut technique. Extensive experiments have been carried out on heterogeneous images to test the accuracy of the proposed method for the segmentation of various types of distributed objects. Examples of application of proposed technique in remote sensing to segment roads and rivers from aerial images are also presented. The visual and objective evaluation and comparison with the existing techniques show that the proposed tool can deliver optimal performance when applied to tough object segmentation tasks.

     

Clump splitting via bottleneck detection and shape classification

Under-segmentation of an image with multiple objects is a common problem in image segmentation algorithms. This paper presents a novel approach for splitting clumps formed by multiple objects due to under-segmentation. The proposed algorithm includes three steps: (1) decide whether to split a candidate connected component by application-specific shape classification; (2) find a pair of points for clump splitting and (3) join the pair of selected points. In the first step, a shape classifier is applied to determine whether a connected component should be split. In the second step, a pair of points for splitting is detected using a bottleneck rule, under the assumption that the desired objects have roughly a convex shape. In the third step, the selected splitting points from step two are joined by finding the optimal splitting line between them, based on minimizing an image energy. The shape classifier is built offline via various shape features and a support vector machine. Steps two and three are application-independent. The performance of this method is evaluated using images from various applications. Experimental results show that the proposed approach outperforms the state-of-the-art algorithms for the clump splitting problem.     

属性形态运算及其在心脏图像分割中的应用

图像分割在心室容积计算中起着建开闭,因为它们都是连通成分的变换.然而,属性形态开闭运算更具普遍性,它们描述更一般化的形状特征并且没有形状改变,它们只测试连通成分是否满足某种递增准则,满足的保留,否则移除.将属性形态运算与梯度算子结合,就构成一种强抗噪性的分割方法.将这些运算应用到有噪声的心脏图像的分割,不仅将噪声去除,而且图像的边缘保留完好,取得满意的效果.     

一种基于灰度级连通性的红外图像分割方法

本文提出一种新的基于灰度级连通性的红外图像分割方法。灰度级连通性认为在某个灰度级以下的所有级集合是连通的，则灰度图像是连通的。提出的图像分割方法使用k级特征开运算将图像中包含目标的k级以上的连通成分保留下来，结合图像弱小目标的特征进行k级连通成分分解运算，提取出包含目标的k级连通成分实现图像简化和目标提取，最后结合简单的二值化处理就能够准确地分割出目标。通过仿真结果的比较，证明在红外图像中这种方法可以实现提高信噪比、提取目标和分割图像的目的。     

Enhanced fog detection and free-space segmentation for car navigation

Free-space detection is a primary task for car navigation. Unfortunately, classical approaches have difficulties in adverse weather conditions, in particular in daytime fog. In this paper, a solution is proposed thanks to a contrast restoration approach on images grabbed by an in-vehicle camera. The proposed method improves the state-of-the-art in several ways. First, the segmentation of the fog region of interest is better segmented thanks to the computation of the shortest routes maps. Second, the fog density as well as the position of the horizon line is jointly computed. Then, the method restores the contrast of the road by only assuming that the road is flat and, at the same time, detects the vertical objects. Finally, a segmentation of the connected component in front of the vehicle gives the free-space area. An experimental validation was carried out to foresee the effectiveness of the method. Different results are shown on sample images extracted from video sequences acquired from an in-vehicle camera. The proposed method is complementary to existing free-space area detection methods relying on color segmentation and stereovision.     

K均值聚类分割的多特征图像检索方法

从图像数据库中快速、准确地检索出所需要的图像,具有广泛的应用前景。针对使用单一图像特征难以准确表达图像之间的差异问题,提出了一种利用颜色聚类分割和形状特征提取的图像检索算法。选择符合人眼视觉特征的HSV空间,分别重组最能描述图像颜色特征的H分量和形状特征的V分量;用K均值聚类算法对两个分量进行聚类分割,得到目标物体;提取目标物体的Hu不变矩和傅里叶描述子来描述形状特征;用欧式距离进行相似度测量并用于图像检索中。采用不同类型图像进行实验,结果表明该算法优于使用单一特征和一般分割方法的图像检索技术。     

图割与非线性统计形状先验的图像分割

提出一种图割与非线性统计形状先验的图像分割方法。首先,在输入空间对输入的形状模板进行配准,得到训练集;其次,采用非线性核函数将目标形状先验映射到特征空间进行主成分分析,获取其投影形状,将此投影形状映射回原输入空间得到目标的平均形状,构成新的能量函数;第三,通过自适应调整形状先验项的权值系数,使能量函数的形状先验项自适应于被分割的图像;最后,用Graph Cuts方法最小化能量函数完成图像分割。实验结果表明,该方法不仅能准确分割与形状先验模板有差别的图像,而且对目标有遮挡或污染的图像也有较好的分割效果,提高了分割效率。