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1.
针对基于像素分析方法不适用于高分辨率影像信息提取的问题,提出一种基于对象的图像分析方法来进行城市建筑信息提取。采用多分辨率图像分割方法得到图像对象,提出非监督的最优尺度判定方法解决单尺度分割造成的欠分割和过分割问题。在对象分类提取过程中,结合LiDAR数据的地形表面高程信息和光谱信息对建筑物进行提取,并利用尺寸、空间位置等信息进行误分类修正。实验区域共提取出18个建筑目标,结果表明所提出的方法有效可行。  相似文献   

2.
主题分割技术是快速并有效地对新闻故事节目进行检索和管理的基础。传统的基于隐马尔可夫模型(HiddenMarkov Model,HMM)的主题分割技术仅使用主题和主题之间的转移寻找主题边界进行新闻分割,并未考虑各主题中词与词之间存在的潜在语义关系。本文提出一种基于隐马尔科夫模型的改进算法。该算法使用潜在语义分析(Latent Se-mantic Analysis,LSA)对词频向量进行特征提取和降维,考虑了词与词之间的上下文关系,通过聚类得到文档类别信息,以LSA特征和主题类别作为HMM的观测和隐状态,这样同时考虑了主题之间的关系,最终实现对文本主题分割。数据实验表明,该算法具有较好的分割性能。  相似文献   

3.
传统的图像压缩技术,大都基于图像空域和色度空间同质性的假定,在文档图像的压缩中并不能取得最好的压缩效果。针对文档图像的特点,提出了一种基于图层分割的文档图像压缩方法。该方法首先利用多尺度的2色聚类算法进行文档图像的图层分割,然后根据不同图层的特征,分别采用效果最佳的压缩技术,能够获得比传统的方法更好的压缩效果。  相似文献   

4.
Document image segmentation is the first step in document image analysis and understanding. One major problem centres on the performance analysis of the evolving segmentation algorithms. The use of a standard document database maintained at the Universities/Research Laboratories helps to solve the problem of getting authentic data sources and other information, but some methodologies have to be used for performance analysis of the segmentation. We describe a new document model in terms of a bounding box representation of its constituent parts and suggest an empirical measure of performance of a segmentation algorithm based on this new graph-like model of the document. Besides the global error measures, the proposed method also produces segment-wise details of common segmentation problems such as horizontal and vertical split and merge as well as invalid and mismatched regions. Received July 14, 2000 / Revised June 12, 2001[-1mm]  相似文献   

5.
This paper presents a wavelet-based texture segmentation method using multilayer perceptron (MLP) networks and Markov random fields (MRF) in a multi-scale Bayesian framework. Inputs and outputs of MLP networks are constructed to estimate a posterior probability. The multi-scale features produced by multi-level wavelet decompositions of textured images are classified at each scale by maximum a posterior (MAP) classification and the posterior probabilities from MLP networks. An MRF model is used in order to model the prior distribution of each texture class, and a factor, which fuses the classification information through scales and acts as a guide for the labeling decision, is incorporated into the MAP classification of each scale. By fusing the multi-scale MAP classifications sequentially from coarse to fine scales, our proposed method gets the final and improved segmentation result at the finest scale. In this fusion process, the MRF model serves as the smoothness constraint and the Gibbs sampler acts as the MAP classifier. Our texture segmentation method was applied to segmentation of gray-level textured images. The proposed segmentation method shows better performance than texture segmentation using the hidden Markov trees (HMT) model and the HMTseg algorithm, which is a multi-scale Bayesian image segmentation algorithm.  相似文献   

6.
巨核细胞图像分割方法的研究   总被引:1,自引:1,他引:1  
随着现代医学研究的飞速发展,显微图像定量分析已经广泛应用到临床诊断、病理分析、癌变分级分类等越来越多的医学领域之内。巨核细胞是骨髓切片图像中个体较大的细胞,形状不规则,对其进行有效提取和分割对骨髓成份统计分析、血液疾病诊断等都有重要意义。该文根据数学形态学的知识,利用直方图势函数提取标记点,并将这些标记点作为种子点来对梯度图进行Watershed变换,进而实现骨髓切片中巨核细胞的有效分割。该方法是一种谱信息与空间信息相结合的分割方法,对分割结果与传统算法的对比分析表明,改进后的算法在分割的完整性和一致性上具有更好的效果。  相似文献   

7.
基于数学形态学的免疫细胞图象分割   总被引:10,自引:1,他引:10       下载免费PDF全文
为了实现对免疫细胞图象的分析,首先要对该种图象进行正确分割,针对这一要求,提出了一种有效的免疫细胞图象分割方法,该方法是根据数学形态学的知识,利用直方图势池数来提取标记点,并将这些标记点作为种子点来对梯度图进行Watershed变换,进而实现了细胞图象的分割。该方法是一种谱信息与空间信息相结合的分割方法,根据实验结果和分析可见,该方法不仅解决了细胞在参数测量前的精确分割问题,同时,为水域分割的关键步骤-种子点的选取找到了一种有效而可靠的方法,实践表明,分割的结果与 目视感受相一致,且其分割速度及可重复性都达到了医学临床的要求。  相似文献   

8.
基于混沌优化的最佳熵阈值的图像分割   总被引:6,自引:0,他引:6  
利用目标在图像中所占比例等信息,结合图像熵阈值算法进行图像的阈值分割。并利用混沌优化的方法一次寻找出图像熵的多个极值点,提高了阈值寻找的效率。仿真实验表明,与传统的图像熵阈值法相比较,该方法能够给出更加合理的分割结果。  相似文献   

9.
针对细胞图像的特点,提出一种改进的基于分水岭算法的细胞图像分割方法。在该方法中.对细胞图像进行数学形态学变换,即采用Top—hat变换后的图像与原始图像相加再减去Bottom—hat变换后的图像以得到最大对比度的图像.继而进行距离变换,最后运用分水岭算法进行分割。实验证明,该改进方法能够得到较好的分割结果。  相似文献   

10.
Optical character recognition for cursive handwriting   总被引:5,自引:0,他引:5  
A new analytic scheme, which uses a sequence of image segmentation and recognition algorithms, is proposed for the off-line cursive handwriting recognition problem. First, some global parameters, such as slant angle, baselines, stroke width and height, are estimated. Second, a segmentation method finds character segmentation paths by combining gray-scale and binary information. Third, a hidden Markov model (HMM) is employed for shape recognition to label and rank the character candidates. For this purpose, a string of codes is extracted from each segment to represent the character candidates. The estimation of feature space parameters is embedded in the HMM training stage together with the estimation of the HMM model parameters. Finally, information from a lexicon and from the HMM ranks is combined in a graph optimization problem for word-level recognition. This method corrects most of the errors produced by the segmentation and HMM ranking stages by maximizing an information measure in an efficient graph search algorithm. The experiments indicate higher recognition rates compared to the available methods reported in the literature  相似文献   

11.
人工干预使蛇模型只能用于半自动的图像分割,该文在梯度向量流(GVF)蛇模型的基础上提出一种基于流场节点与最小路径方法的全自动图像分割算法。在图像的GVF场上检测出流场节点,以节点为种子,采用多标记快速扫描法获得一个初始分割,采用区域合并得到最终分割结果。实验结果证明了该算法的鲁棒性和有效性。  相似文献   

12.
This paper proposes a new approach to the water flow algorithm for text line segmentation. In the basic method the hypothetical water flows under few specified angles which have been defined by water flow angle as parameter. It is applied to the document image frame from left to right and vice versa. As a result, the unwetted and wetted areas are established. These areas separate text from non-text elements in each text line, respectively. Hence, they represent the control areas that are of major importance for text line segmentation. Primarily, an extended approach means extraction of the connected-components by bounding boxes over text. By this way, each connected component is mutually separated. Hence, the water flow angle, which defines the unwetted areas, is determined adaptively. By choosing appropriate water flow angle, the unwetted areas are lengthening which leads to the better text line segmentation. Results of this approach are encouraging due to the text line segmentation improvement which is the most challenging step in document image processing.  相似文献   

13.
基于自适应特征与多级反馈模型的中英文混排文档分割   总被引:2,自引:0,他引:2  
提出了一种基于自适应特征与多级反馈模型的新颖的字符分割方法,对文字图像质量与中英文混排格式有较好的自适应能力.该方法的主要思想就是将一个分割过程分成很多层,每层都会由一个主要特征来指导字符分割与中英文预分类,然后将分割层的结果反馈至当前分割层或前面的分割层,并指导下一层的分割.该方法将字符分割、中英文预分类和字符识别这三者进行了很好的融合,大大提高了字符分割与识别的正确率.  相似文献   

14.
一种基于二维隐马尔可夫模型的图像分类算法   总被引:2,自引:0,他引:2  
针对图像分块之间的相互依赖关系,提出一种基于二维隐马尔可夫模型的图像分类算 法。该算法将一维隐马尔可夫模型扩展成二维隐马尔可夫模型,模型中相邻的图像分块在平面两个 方向上按条件转移概率进行状态转换,反应出两个维上的依赖关系。隐马尔可夫模型参数通过期望 最大化算法(EM)来估计。同时,本文利用二维Viterbi算法,在训练隐马尔可夫模型的基础上,实现 对图像进行最优分类。文件图像分割的应用表明,隐马尔可夫算法优于CART算法。  相似文献   

15.
针对高分遥感影像中存在地物数目多,特征信息复杂导致分割边缘不清晰、对象细节丢失等问题,提出一种改进的超像素分割和多特征结合的遥感影像分割合并算法。在对图像进行分割前的预处理阶段,使用超像素分割技术得到初始分割图像;区域合并过程中,基于对象间的异质性和对象内部的同质性,结合光谱、纹理和形状特征,对对象进行合并;通过调整全局分割参数来调整合并尺度,得到最终的影像分割结果。实验结果表明,所提方法能得到较好的影像分割效果。  相似文献   

16.
本文研究了一种基于形态学处理和纹理特征合并的水域算法,该方法首先对形态梯度图进行滤波处理,以获得较好的参考图像,然后又利用图像的直方图势函数对图像做标记。最后,为了获得整体的目标,我们对上面所得到的分割结果进行了区域一致性、纹理一致性和对比度的检验,来合并用水域算法获得的分割结果,以曩得更好的分割效果,
,并通过试验验证了算法的有效性。  相似文献   

17.
基于一种改进禁忌搜索算法优化离散隐马尔可夫模型   总被引:1,自引:0,他引:1  
隐马尔可夫模型(HMM,HiddenMarkovModel)是语音识别和手势识别中广泛使用的统计模式识别方法。文章提出了一种改进的禁忌搜索(ITS,ImprovedTabuSearch)优化HMM的参数。传统的TabuSearch(TS)与局部搜索算法(极大似然法)交替进行,从而加快了算法的收敛速度,并得到优化解。分别用TS及ITS训练隐马尔可夫模型进行动态手势识别。结果表明ITS可获得更高的识别率,且能达到全局优化。  相似文献   

18.
周晚辉  刘文萍 《计算机工程》2010,36(24):211-213
模糊C均值算法是图像分割的常用方法,但该算法对噪声非常敏感。为此,提出一种新算法,在模糊C均值算法基础上引进Type-2模糊理论,以提高算法的分割准确性和鲁棒性。该算法对模糊C均值算法中每一个样本的隶属度进行分段线性拉伸,利用拉伸的结果作为一个新的隶属度函数,并用该函数对图像进行分割。实验结果表明,该算法准确性较高,且具有良好的抗噪能力。  相似文献   

19.
探讨了利用Gabor小波和隐马尔可夫模型(HMM)进行人脸识别的方法,首先对人脸图像进行多分辨率的Gabor小波变换;然后在图像上放置一组网格结点,每个结点用该结点处的多尺度Gabor幅度特征描述,采用独立元分析法对每个结点进行去相关和降维;最后形成特征结,把每个特征结作为观测向量,对隐马尔可夫模型进行训练,并将优化的模型参数用于人脸识别,ORL人脸库的实验结果表明,该方法识别率高,工程上易于应用。  相似文献   

20.
Segmentation of high spatial resolution remotely sensed image is the important foundation of Object\|Based Image Analysis(OBIA), most of the image segmentation algorithms involve the problem of parameter setting. Self\|adaptive Parameterization is one of the key factors that affect the efficiency and effectiveness of remote sensing image segmentation. Considering that traditional watershed segmentation algorithm is susceptible to noise and the segmentation scale parameter is difficult to be self\|adaptively chosen,this paper propose a scale self\|adaptive method in watershed segmentation. After median filtering in primary image, this paper uses spatial statistical method to realize the self\|adaptive setting of watershed segmentation parameters, and then segments the high spatial resolution remote sensing image. This study uses IKONOS and Quickbird multispectral images as experimental data to testify the validity of the method proposed by this paper. The homogeneity within the segmentation parcels and the heterogeneity between thesegmentation parcels are used to build up a synthetic evaluation model to quantitatively evaluate the segmentation results by the proposed method by comparing with different parameter sequences segmentation results. The comparison result show that the proposed method perform well in high spatial resolution image segmentation. As result, the method proposed in this paper not only improves the accuracy of image segmentation to a certain extent, but also raises the automation of the segmentation parameter selection, which provides a new way for image segmentation and the research of parameterization in the future.  相似文献   

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