计算机科学 ›› 2015, Vol. 42 ›› Issue (9): 309-312.doi: 10.11896/j.issn.1002-137X.2015.09.061

• 图形图像与模式识别 • 上一篇    下一篇

基于聚类方法的对象阴影识别方法研究

张晓丹,李春来,金兆岩   

  1. 吉首大学信息科学与工程学院 吉首416000,吉首大学信息科学与工程学院 吉首416000,国防科学技术大学计算机学院 长沙410073
  • 出版日期:2018-11-14 发布日期:2018-11-14
  • 基金资助:
    本文受湖南省自然科学基金资助

Clustering Based Object Shadow Recognition Algorithm

ZHANG Xiao-dan, LI Chun-lai and JIN Zhao-yan   

  • Online:2018-11-14 Published:2018-11-14

摘要: 图像处理中的对象阴影计算影响着图像的渲染速度,是图像处理领域的重要研究内容。为了进一步提高对象阴影的渲染速度,提出了一种基于聚类方法的对象阴影识别方法。按照光线的衰减半径将光线表示为一个个球体,当球体之间的距离大于预定义的最小距离时,将其划分到两个不同的类中,采用自上而下的层次方法对光线进行聚类。在聚类过程中,光线的衰减半径随着与光源的距离呈线性增长。对光线进行聚类分析后,对同一聚类内的光线采用相同的渲染方式,因而提高了阴影的渲染效率。最后通过实验验证了提出的方法的有效性。

关键词: 对象渲染,阴影计算,聚类,图像处理

Abstract: Object shadow computation is a critical issue for object rendering in image processing,and thus it is an important research issue in image processing field.In order to further improve the efficiency of shadow rendering,this paper proposed a clustering based object shadow recognition algorithm.We represented each light as a sphere according to its attenuation range,classified lights into different classes while the distance between them extended the predefined minimum distance,and applied a top-down hierarchal clustering method for lights.During the process of clustering,the attenuation range of light increases linearly with the distance between light and the light source.After clustering the lights into different classes,we rendered lights of a class by the same texture,and thus,the efficiency of rendering shadow in an image is improved largely.Finally,we validated the efficiency of our algorithm according to some experiments.

Key words: Object rendering,Shadow computation,Clustering,Image processing

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