基于边缘保持的区域能量最小化SAR海冰图像分割

提出了一种基于边缘保持的区域能量最小化的SAR海冰图像分割算法。首先对图像进行SRAD滤波,然后进行分水岭初始分割和区域能量最小化分割,从而得到最终分割结果。将该算法用于SAR海冰图像的分割中,实验结果表明,该分割方法有效、准确性好。     

一种基于先验知识的分水线彩色图像分割方法

提出了一个结合彩色信息的分水线图像分割方法，在LUV颜色空间的分水线图像上，使用贝叶斯推理的图像分割方法。对图像进行LUV彩色空间上的分水线变换，在分水线图像上进行基于彩色信息的各个区域能量的计算，通过选择最小能量的目标，依次找出最理想的目标区域。设计了一个先验密度惩罚图像当中分水线变换后的相似的区域，图像分割进而变成对目标子集的最大后验估计。逐步地找出最理想目标区域和背景区域。这一方法同时结合使用了彩色信息和空间信息；可以有效地解决分水线变换后的过分割问题，利用了先验知识和彩色信息。实验结果显示，该方法有较好的分割结果。     

多级水脊线算法在二维医学超声图像中的应用

以肝囊肿超声图像为例,介绍一种新的医学超声图像的分割方法：多级水脊线分割算法在医学二维超声图像分割中的应用。由于斑点噪声和超声衰减产生的假象,二维和三维超声成像中的图像分割问题一直是公认的一大难点。本文采用由若干数学形态学辅助的水脊线方法提取超声图像中的肝囊肿边缘,取得了相当令人满意的结果,这为进一步的图像处理和化疗等治疗手段奠定了必要的基础。该方法自动选择并分割图像中的主要目标对象,从而克服了传统水脊线算法中常见的过分割和改进水脊线算法中半自动的缺陷。     

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。     

Multispectral image segmentation by a multichannel watershed‐based approach

Watershed transformation in mathematical morphology is a powerful morphological tool for image segmentation that is usually defined for greyscale images and applied to the gradient magnitude of an image. This paper presents an extension of the watershed algorithm for multispectral image segmentation. A vector‐based morphological approach is proposed to compute gradient magnitude from multispectral imagery, which is then input into watershed transformation for image segmentation. The gradient magnitude is obtained at multiple scales. After an automatic elimination of local irrelevant minima, a watershed transformation is applied to segment the image. The segmentation results were evaluated and compared with other multispectral image segmentation methods, in terms of visual inspection, and object‐based image classification using high resolution multispectral images. The experimental results indicate that the proposed method can produce accurate segmentation results and higher classification accuracy, if the scales and contrast parameter are appropriately selected in the gradient computation and subsequent local minima elimination. The proposed method shows encouraging results and can be used for segmentation of high resolution multispectral imagery and object based classification.     

基于运动估计的交互式医学图像序列分割

针对医学图像难以自动分割,而医学图像序列采用手工分割时工作量巨大、效率低的问题,提出了一种新的交互式图像序列分割方法.在计算机的辅助下,用手工精确地描画出第一幅图像中对象的边界轮廓.后续图像的分割曲线用运动估计的方法自动得到.每完成一幅图像的分割用户都可以检查分割效果,如果不满意则可用手工修正.这个过程重复进行,直到整个图像序列分割完毕.实验结果表明,该方法能精确、快速地实现医学图像序列的分割.     

Normalized Cut与分水岭变换在高光谱影像混合像元端元提取中的应用

现有的遥感影像端元提取方法主要是从光谱特征角度提出,而结合空间信息的端元提取方法是近些年遥感影像混合像元分解的研究热点,为此使用图论的图像分割Normalized Cut与分水岭变换方法提出了一种改进的空间预处理模型用于高光谱遥感影像混合像元的端元提取。该方法在混合像元端元提取过程中不仅利用遥感影像的光谱信息而且引入了像元的空间位置信息,实验结果表明本文提出的端元提取方法与现有的方法相比提高了遥感影像的混合像元分解精度。     

基于最大流的交互式目标提取算法

医学图像处理中,目标提取在准确区分组织结构中起了重要的作用,论文介绍了基于最大流的交互式的目标提取算法,该方法把基于区域和基于边界方法结合起来,并用分水岭算法对图像做预分割,在其所分的区域上计算能量函数,然后最小化能量函数求最优边界。笔者结合自己研究的课题,针对目标标记步骤中聚类种子F和#色彩值的k-means算法进行改进,并把改进算法应用到人体器官切片目标分割中。     

Multiresolution-based watersheds for efficient image segmentation

This paper presents an efficient method for image segmentation based on a multiresolution application of a wavelet transform and watershed segmentation algorithm. The procedure toward complete segmentation consists of four steps: pyramid representation, image segmentation, region merging and region projection. First, pyramid representation creates multiresolution images using a wavelet transform. Second, image segmentation segments the lowest-resolution image of the pyramid using a watershed segmentation algorithm. Third, region merging merges the segmented regions using the third-order moment values of the wavelet coefficients. Finally, the segmented low-resolution image with label is projected into a full-resolution image (original image) by inverse wavelet transform. Experimental results of the presented method can be applied to the segmentation of noise or degraded images as well as reduce over-segmentation. In addition, we applied our method to human face detection with accurate and closed boundaries.     

基于冰情图的极地SAR海冰图像分割

冰情图在极区安全航行、气候研究等方面具有重要价值,但其存在不能提供像素级的定位信息、对密集度的估计较粗略等缺陷。基于此,提出一种基于冰情图的边缘保持区域型MRF分割方法。依据冰情图从SAR图像中提取子图像,进行SRAD滤波、分水岭初始分割、区域型MRF分割,合并各子图像得到最终分割结果,实现人工解译和计算机解译的结合,得到像素级的结果,具有物体边缘定位准确、分割效率高、可并行化处理等优点。实验结果表明,该方法对极区SAR海冰图像均具有良好的分割效果。     

Watershed from propagated markers: An interactive method to morphological object segmentation in image sequences

In this paper, it is introduced an interactive method to object segmentation in image sequences, by combining classical morphological segmentation with motion estimation – the watershed from propagated markers. In this method, the objects are segmented interactively in the first frame and the mask generated by its segmentation provides the markers that will be used to track and segment the object in the next frame. Besides the interactivity, the proposed method has the following important characteristics: generality, rapid response and progressive manual edition. This paper also introduces a new benchmark to do quantitative evaluation of assisted object segmentation methods applied to image sequences. The evaluation is done according to several criteria such as the robustness of segmentation and the easiness to segment the objects through the sequence.     

基于改进分水岭的棉花图像分割方法

针对棉花图像中存在阳光直射和阴影遮挡等因素而导致图像分割精度低、效果差的问题,提出一种改进分水岭的图像分割算法。该方法对原始图像进行各向异性扩散去噪预处理;利用鲁棒中值估计对形态学多尺度梯度图像进行硬阈值法梯度修正;对修正后的图像采用分水岭算法进行分割,对过分割的区域采用基于L*a*b*彩色空间的颜色相似度方案进行区域合并,从而将棉花提取出来。实验结果表明,提出的算法对阳光直射及阴影遮挡等干扰条件下的棉花图像分割能取得较好的效果。     

Striped-texture image segmentation with application to multimedia security

In today’s rapid growth of volume of multimedia data, security is important yet challenging problem in multimedia applications. Image, which covers the highest percentage of the multimedia data, it is very important for multimedia security. Image segmentation is utilized as a fundamental preprocessing of various multimedia applications such as surveillance for security by breaking a given image into multiple salient regions. In this paper, we present a new image segmentation approach based on frequency-domain filtering for images with stripe texture, and generalize it to lattice fence images. Our method significantly reduces the impact of stripes on segmentation performance. The approach proposed in this paper consists of three phases. Given the images, we weaken the effect of stripe texture by filtering in the frequency domain automatically. Then, structure-preserving image smoothing is employed to remove texture details and extract the main image structures. Last, we use an effective threshold method to produce segmentation results. Our method achieves very promising results for the test image dataset and could benefit a number of new multimedia applications such as public security.

     

用于立体视频会议系统的立体对象分割与跟踪算法

基于对象的立体视频编码压缩技术能在立体视频会议系统中得到很好的应用，从立体视频信号中正确分割出立体视频对象是基于对象的立体视频编码压缩的一个前提条件，基于立体视频会议图像序列的时空特性和左右通道间的视差特性，提出了一种立体视频对象分割与跟踪算法，首先利用空域分割和运动检测相结合的方法，提取左通道中的运动物体；然后，提出一种左右通道间基于边缘轮廓的二级视差匹配算法，并根据已分割的左通道运动对象提取右通道的视频运动对象；最后利用对象边界轮廓的跟踪方法对后续图像中的运动对象进行快速跟踪，实验结果说明文中算法能够应用于立体视频会议图像序列的立体对象分割与跟踪。     

图像单个运动目标识别与跟踪的一种解决方案

就图像单个运动目标识别和跟踪问题提出了一种解决方案。在图像分割部分,提出了基于数学形态学中流域分割的实现方法,依据单运动目标的特征通过合并过渡分割区域算法较好地解决了过度分割的现象,实现无需人工设置任何阈值,全智能化图像分割;在目标提取部分,提出了一种在连续多帧图像中自动提取单运动目标的方法,能适应摄像头固定和摄像头随运动目标移动等各种情况;在目标跟踪部分,对进行匹配的模板设置掩码,并自动进行调整,使得对运动目标的跟踪更为鲁棒。     

Watershed-based hierarchical SAR image segmentation

Watershed transformation is a powerful image segmentation tool recently developed in mathematical morphology. In order to segment images initially oversegmented by watershed transformation, two approaches are considered: one is the thresholding of the gradient image proposed by us which is capable of keeping more salient image contours; the other is the well known centroid linkage region growing algorithm which merges regions with certain statistical similarities. By choosing suitable thresholds in the two approaches, hierarchical image segmentation algorithms can be constructed. A Ratio of Averages (ROA) edge detector is proposed to replace the morphological edge detectors prior to watershed transformation when applied to Synthetic Aperture Radar (SAR) images. Applications to SAR agricultural image segmentation with these hierarchical segmentation algorithms are presented. It is demonstrated that the algorithms are efficient in the segmentation of the SARimages and appropriate for land use applications when the land cover is made up of individual plots.     

A marker-based watershed method for X-ray image segmentation

Digital X-ray images are the most frequent modality for both screening and diagnosis in hospitals. To facilitate subsequent analysis such as quantification and computer aided diagnosis (CAD), it is desirable to exclude image background. A marker-based watershed segmentation method was proposed to segment background of X-ray images. The method consisted of six modules: image preprocessing, gradient computation, marker extraction, watershed segmentation from markers, region merging and background extraction. One hundred clinical direct radiograph X-ray images were used to validate the method. Manual thresholding and multiscale gradient based watershed method were implemented for comparison. The proposed method yielded a dice coefficient of 0.964 ± 0.069, which was better than that of the manual thresholding (0.937 ± 0.119) and that of multiscale gradient based watershed method (0.942 ± 0.098). Special means were adopted to decrease the computational cost, including getting rid of few pixels with highest grayscale via percentile, calculation of gradient magnitude through simple operations, decreasing the number of markers by appropriate thresholding, and merging regions based on simple grayscale statistics. As a result, the processing time was at most 6 s even for a 3072 × 3072 image on a Pentium 4 PC with 2.4 GHz CPU (4 cores) and 2G RAM, which was more than one time faster than that of the multiscale gradient based watershed method. The proposed method could be a potential tool for diagnosis and quantification of X-ray images.     

基于动态合并准则的分水岭算法在医学图像中的应用

针对医学图像的模糊特点和实际应用的要求, 提出了一种基于动态合并准则的分水岭分割方法。阐述了在分水岭算法的基础上做的一些改进，通过动态合并准则进行边分割边合并，有效地抑制了过分割现象。结果表明，该方法能够快速、准确地得到医学图像的分割结果，并且具有较强的抗噪声能力。     

一种改进的分水岭图像分割算法

分水岭算法在医学图像分割中有着广泛的应用。针对传统分水岭分割算法对噪声敏感和严重的过分割问题．本文提出了一种基于数学形态学的改进的分水岭图像分割算法。通过前期的预处理和汇水盆地的选取，有效地抑制了过分割现象。实验表明，该算法能够对血细胞图像进行快速、准确的分割，边缘定位精确，并且能够较好的克服噪声对图像的影响。