基于方向统计和阴影形状的人脸图像分析Facial Image Analysis using Directional Statistics and Shape-from Shading |
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课程网址: | http://videolectures.net/wapa2010_hancock_fiad/ |
主讲教师: | Edwin Hancock |
开课单位: | 约克大学 |
开课时间: | 2010-09-20 |
课程语种: | 英语 |
中文简介: | 虽然使用形状从阴影恢复面部形状是一个吸引人的想法,但它被凹凸模糊,可变反照率,自阴影和非朗伯反射等问题所困扰。因此,魔鬼寓于细节之中。在这个演讲中,我将展示如何通过在从阴影中变形的过程中合并一个表面法向的统计模型来克服这些问题。本讲座的主要贡献在于,利用制图学的等距方位角投影,建立了表面法线分布的表示法,将单位球面上的表面法线方向分布转换为切平面上的点分布。我将展示如何通过使用健壮的统计数据将统计模型拟合到图像亮度数据,从而使该模型适合于处理阴影。我还将通过拟合一个既能捕捉闪亮表面又能捕捉粗糙表面行为的反射率模型,展示如何调整这个过程来处理非朗伯式的反射率。最后,我将展示该过程所传递的形状信息如何用于人脸识别和性别确定。本次讲座将提供Smith and Hancock (PAMI 07, IJCV09, IJCV 2010)和Wu, Smith and Hancock (IVC 2010)近期工作的概要。 |
课程简介: | Although the recovery of facial shape using shape-from-shading is an appealing idea, it is frustrated by problems such as concave-convex ambiguities, variable albedo, self shadowing and non-Lambertian reflectance. As such the devil resides in the detail. In this talk I will show how these problems can be overcome by incorporating a statistical model for surface normal direction within the shape-from-shading process. The main contribution of the talk is to develop a representation of the distribution of surface normals using the equidistant azimuthal projection from cartography, which transforms a distribution of surface normal direction on a unit sphere to a distribution of points on a tangent plane. I will show how this model can be adapted to deal with shadowing by fitting the statistical model to image brightness data using robust statistics. I will also show to to adapt the process to deal with non-Lambertian reflectance, through fitting a reflectance model that can capture the behavour of both shiny and rough surfaces. Finally, I will show how the shape information delivered by the process can be used to perform face recognition and gender determination. This talk will provide a synopsis of recent work by Smith and Hancock (PAMI 07, IJCV09, IJCV 2010) and Wu, Smith and Hancock (IVC 2010) |
关 键 词: | 计算机科学; 计算机视觉; 脸部和手势分析 |
课程来源: | 视频讲座网 |
最后编审: | 2019-10-29:lxf |
阅读次数: | 158 |