首页> 外文会议>Computational imaging XI >Subspace Methods for Computational Relighting
【24h】

Subspace Methods for Computational Relighting

机译:计算照明的子空间方法

获取原文
获取原文并翻译 | 示例

摘要

We propose a vector space approach for relighting a Lambertian convex object with distant light source, whose crucial task is the decomposition of the reflectance function into albedos (or reflection coefficients) and lightings based on a set of images of the same object and its 3-D model. Making use of the fact that reflectance functions are well approximated by a low-dimensional linear subspace spanned by the first few spherical harmonics, this inverse problem can be formulated as a matrix factorization, in which the basis of the subspace is encoded in the spherical harmonic matrix S. A necessary and sufficient condition on S for unique factorization is derived with an introduction to a new notion of matrix rank called nonseparable full rank. An SVD-based algorithm for exact factorization in the noiseless case is introduced. In the presence of noise, the algorithm is slightly modified by incorporating the positivity of albedos into a convex optimization problem. Implementations of the proposed algorithms are done on a set of synthetic data.
机译:我们提出了一种向量空间方法,用远距离光源对朗伯凸物体进行重新照明,其关键任务是根据同一物体及其图像的一组图像将反射函数分解为反照率(或反射系数)和照明。 D模型。利用这样的事实,即反射函数可以很好地近似为由前几个球谐函数所覆盖的低维线性子空间,因此可以将这一反问题公式化为矩阵分解,其中子空间的基础被编码为球谐函数引入唯一的矩阵分解新的矩阵秩概念,即不可分的全秩,从而得出唯一分解的S的充要条件。介绍了一种基于SVD的无噪声情况下精确分解的算法。在存在噪声的情况下,通过将反照率的正性纳入凸优化问题中,对该算法进行了稍微修改。拟议算法的实现是在一组综合数据上完成的。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号