【作者】 张静；

【导师】 王宏漫；

【作者基本信息】 辽宁师范大学 ， 计算机应用技术， 2012， 硕士

【摘要】 骨架提取在计算机图形学和可视化领域的许多应用中是一个基本的问题,被广泛应用于目标检测、图像处理、模式识别、虚拟导航、计算机动画等领域。目前已有多种骨架提取算法,使用的三维或二维模型多数是以离散体素或者网格曲面形式表示的,而近年来在点云上进行骨架提取的算法也是一个热点。在前人研究的基础上,本文提出：(1)改进的汉字骨架提取算法。通过研究一种不完整点云的骨架提取算法,将该算法中的某些思想应用于汉字骨架提取中。该方法首先对汉字进行边缘检测,获取汉字的边缘,汉字边缘可以看作二维简单点云,将点云存储在数组Iedge中,在数组中按特定步长取点,然后计算每个步长范围内的内切圆,最后将各内切圆的圆心连接起来得到汉字的骨架。(2)形态学骨架提取算法进行纹理边界提取。采用标准差直方图作为统计特征进行纹理分析,并利用X2统计方法度量直方图之间的相似性,根据直方图的相似性采用形态学骨架提取方法获得最后的纹理边界。汉字骨架提取算法在其算法原型的基础上进行了改进,其原型仅适用于TrueType字体,而本文的算法不仅可以操作于TrueType字体,对于其他的字体如隶书、黑体、华文新魏等字体同样适用。基于形态学骨架提取算法进行纹理边界提取算法中,提出标准差直方图的概念,并以直方图相似性和骨架提取算法为基础,构造了一种新的纹理边界提取方法,算法的计算效率较高。更多还原

【Abstract】 Skeleton extraction is a fundamental problem with many applications in the field of computer graphics and visualization, which are widely used for many tasks including target detection, image processing, pattern recognition, virtual navigation and computer animation, etc. The3D or2D model used by most existing skeleton extraction methods makes use of a volumetric discrete representation or mesh surface representation. In recent years, the algorithm for skeleton extraction from point clouds has become a hot theme.Based on previous research, we present:(1) Improved algorithm of Chinese characters skeleton extraction. By learning the algorithm of curve skeleton extraction from incomplete point cloud, we use some algorithms of it in our skeleton extraction algorithm. In our algorithm, firstly, detect the edge of the Chinese character, the edge can be seen as a simple point clouds in2D.The point clouds are stored in the array, get the points by specific step, then calculate inscribed circle within the specific step iteratively, get the skeletons of the Chinese character after connecting every center of the inscribed circle.(2) Texture boundary extraction based on morphological skeleton extraction algorithm. We employ a standard deviation histogram as a statistic feature for texture analysis, and similarity among multiple histograms is measured using diagonal χ2-statistic method. According to the similarity among standard deviation histograms, we adopt skeleton extracting method based on mathematical morphology to obtain the final texture region boundary.The skeleton extraction algorithm of Chinese characters based on the prototype algorithm has been improved. The prototype of Chinese characters skeleton extraction algorithm can only use for TrueType fonts, and this method not only for TrueType fonts, but also for other fonts, such as Official script, bold, new Chinese Wei, etc. In the algorithm of texture boundary extraction based on morphological skeleton extraction, we proposed the concept of standard deviation histogram, according to the similarity among standard deviation histograms and morphological skeleton extraction, we constructed a new texture boundary extraction method, and it has high computational efficiency.更多还原