A Bucket Grid Structure to Speed Up Table Lookup in Gauge-Based Photometric Stereo
A Bucket Grid Structure to Speed Up Table Lookup in Gauge-Based Photometric Stereo
复制标题
DOI：
10.1109/sibgrapi.2007.16
复制
发表时间：
2007-10
期刊：
影响因子：
--
通讯作者：
H. C. G. Leitão;R. Saracchini;J. Stolfi
中科院分区：
文献类型：
--
作者：
H. C. G. Leitão;R. Saracchini;J. Stolfi
在本文中，我们展示了如何在基于量规的多图像光度立体中加快表查找步骤。在这一步中，必须找到一个已知形状和颜色的测量对象的像素，其外观在m个不同照明场下与给定场景像素相似。这种搜索简化为在一个有一千个或更多m-向量的表中找到与给定m-向量最接近的匹配。我们的加速方法利用了表实际上是m维空间中相当平坦的二维流形这一事实，因此可以使用二维桶网格结构有效地解决搜索问题。
In this paper, we show how to speed up the table lookup step in gauge-based multi-image photometric stereo. In that step, one must find a pixel of a gauge object, of known shape and color, whose appearance under m different illumination fields is similar to that of a given scene pixel. This search reduces to finding the closest match to a given m- vector in a table with a thousand or more m-vectors. Our speed-up method exploits the fact that the table is in fact a fairly flat two-dimensional manifold in m-dimensional space, so that the search can be efficiently solved with a two-dimensional bucket grid structure.