November 2, 2013 -
I am in the midst of my PhD qualifying exams, so bear with me until I am done on the 12th of November and can get back to processing all the coral mapping data from our trip to Ofu!
Update (December 13, 2013) - I passed! Officially a PhD candidate. Some new results added below. I am in sore need of new equipment to process all the 3D data - check out the new Vedphoto store and holiday sale if you can. All proceeds go to funding the Reactive Reefs project and providing this data free to the public!
However, as part of my research presentation, I did manage to make the first 3D map of the underwater reef from just a snippet of the full data set. After many grueling computer hours and over 9 hours of processing on an 8-core machine + GPU I have at last a preliminary 3D map! The reconstruction actually worked much better than I had imagined, though to finish the entire map I will surely need much better computational resources. The maps below have over 3.5 million polygons! Need to bump that up to ~100 million for the maximum resolution.
The basic idea behind the 3D reconstruction is to use otherwise discarded data from the Fluid Lensing process and exploit the motion of the quad-copter over the reef. Fluid Lensing removes all the surface distortions from image sets, so I can accurately triangulate the distance to each voxel (three-dimensional pixel). Once I have a point cloud of data points, the computationally intensive process of fitting a surface to those points begins. Once the surface texture is computed and discretized into millions of small polygons, I can overlay the high-resolution texture that Fluid Lensing provides. Below is a schematic of how the imaging was captured. As the quadcopter moves about the surface, it creates a stereographic baseline to view the same surface from multiple points (like your eyes). This allows a distance to be computed and a 3D surface to be rendered.
Here is a close up of the rendered 3D surface showing the 3D geometry of the corals beneath the ocean surface!
coral high shading render
Here is the 3D modeled covered with the high-resolution Fluid Lensed map: coral high texture render
And a brief animation exploring the 3D environment. Sorry about the lag - I will need to get the funds together to build a dedicated 3D map-processing desktop that can handle the graphics and reduce the render time. Preliminary Coral Reef 3D map
More to come soon!