Stereoscopic cloud base reconstruction using high-resolution whole sky imagers

Cloud base height and volume estimation is needed in meteorology and other applications. We have deployed a pair of custom-designed Whole Sky Imagers, which capture stereo pictures of the sky at regular intervals. Using these images, we propose a method to create rough 3D models of the base of clouds, using feature point detection, matching, and triangulation. The novelty of our method lies in the fact that it locates the cloud base in all three dimensions, instead of only estimating cloud base height. For validation, we compare the results with measurements from weather radar.

[1]  Stefan Winkler,et al.  Cloud base height estimation using high-resolution whole sky imagers , 2015, 2015 IEEE International Geoscience and Remote Sensing Symposium (IGARSS).

[2]  Stefan Winkler,et al.  Design of low-cost, compact and weather-proof whole sky imagers for high-dynamic-range captures , 2015, 2015 IEEE International Geoscience and Remote Sensing Symposium (IGARSS).

[3]  Stefan Winkler,et al.  Geo-referencing and stereo calibration of ground-based Whole Sky Imagers using the sun trajectory , 2016, 2016 IEEE International Geoscience and Remote Sensing Symposium (IGARSS).

[4]  Steven Fortune,et al.  Voronoi Diagrams and Delaunay Triangulations , 2004, Handbook of Discrete and Computational Geometry, 2nd Ed..

[5]  Evgueni I. Kassianov,et al.  Cloud-Base-Height Estimation from Paired Ground-Based Hemispherical Observations , 2005 .

[6]  Richard Szeliski,et al.  A Comparison and Evaluation of Multi-View Stereo Reconstruction Algorithms , 2006, 2006 IEEE Computer Society Conference on Computer Vision and Pattern Recognition (CVPR'06).

[7]  Yee Hui Lee,et al.  Performance of Site Diversity Investigated Through RADAR Derived Results , 2011, IEEE Transactions on Antennas and Propagation.

[8]  E. Baltsavias,et al.  Cloud mapping from the ground: use of photogrammetric methods , 2002 .

[9]  Stefan Winkler,et al.  Color-Based Segmentation of Sky/Cloud Images From Ground-Based Cameras , 2016, IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing.

[10]  W. Philip Kegelmeyer,et al.  The computation of cloud base height from paired whole-sky imaging cameras , 1997, Machine Vision and Applications.

[11]  Stefan Winkler,et al.  Estimation of solar irradiance using ground-based whole sky imagers , 2016, 2016 IEEE International Geoscience and Remote Sensing Symposium (IGARSS).

[12]  Stefan Winkler,et al.  WAHRSIS: A low-cost high-resolution whole sky imager with near-infrared capabilities , 2014, Defense + Security Symposium.

[13]  Jitendra Malik,et al.  Recovering high dynamic range radiance maps from photographs , 1997, SIGGRAPH '08.

[14]  Shilpa Manandhar,et al.  Weather radar to detect cloud occurrence level , 2016, 2016 IEEE Region 10 Conference (TENCON).

[15]  G LoweDavid,et al.  Distinctive Image Features from Scale-Invariant Keypoints , 2004 .

[16]  Janet E. Shields,et al.  Day/night whole sky imagers for 24-h cloud and sky assessment: history and overview. , 2013, Applied optics.