Seminar by Dr. Herbert Yang (University of Alberta)
Speaker: Dr. Herbert Yang (Dept. of Computing Science
University of Alberta)
Title: Computer Vision of Refractive Media
Date: Monday, December 17th, 2018
Computer vision of opaque objects has been extensively studied. However,there is significantly less attention on refractive media. In this talk, I will give an overview of my recent research in the area of computer vision of refractive media, which includes solids and uids. My interest in this topic began several years ago when my group was asked to develop an undersea 3D vision system for Neptune Canada, which had been merged with Venus Canada to form Ocean Networks Canada. During our research, we discovered that simply applying land-based computer vision techniques to undersea appears trivial but is, unfortunately, incorrect. Surprisingly, most photogrammetry methods at the time incorrectly adapted land-based methods to undersea applications with minortweaking of parameters. By accommodating refraction in our methods, we have developed several physics based algorithms that outperform the accuracy of existing algorithms.Rather than a hindrance, we also discovered that refraction can be leveraged in underwater imaging. For example, we take advantage of dispersion to calibrate an underwater camera with improved accuracy. As well, dispersion can also be used to reconstruct an object in 3D withonly one single view, i.e. one single camera, which is not possible for a typical land-based camera. More recently, motivated by our underwater results, we further explore developing new physics based methods to reconstruct shapes of transparent objects, which include transparent solids and dynamic water surfaces and underwater scenes.
Dr. Herbert Yang is a full professor in the Dept. of Computing Science at the University of Alberta. He received his Ph.D. from the University of Pittsburgh. He is a senior member of the IEEE and serves as Associate Editor for the journal Pattern Recognition. He has published over 80 technical papers in international journals and conference proceedings. In addition, he has served as referee to numerous international journals and conferences. He was co-chair of Vision Interface 98. His research interests include Computer Graphics, Computer Vision and Multimedia Communications. Topics include 2D and 3D shape analysis, edge detection, segmentation, motion analysis, ultrasound image processing, colour image processing, physics-based modelling and animation, rendering of realistic imagery, and image-based rendering.