How can I plot a set of 2D ground penetrating radar sections in 3D, as rendered 2D images that have the appearance of 3D slices? [An analogy might be that I have a set of paintings, which I want to stack in a rack. The rack creates a 3D geometry for viewing the paintings, but the canvases themselves are still 2D.]
I have data from a series of parallel radar scans through a highway. Each scan generated a time series that can be arranged as xyzA where in a simple case: x is distance along the line, y is a constant for each line, z is depth, and A is the radar signal's amplitude. A typical scan comprises ~3 million data points.
A single scan can be displayed in 2D using imagesc (using the x,z, and A components). My task is to visualize the data in 3D. In theory, I could interpolate all of the scanned data to make a 3D volume, and slice it, but that will not differentiate between noise and signal, and is likely to create persistent artifacts. Instead, I'd like to just display a series of 2D slices in 3D space, where each slice is an individual scan.
This sounds like a trivial problem (after all, a 3 million point slice is equivalent to a low-resolution photo, and 3D perspective computer games handle this kind of problem in real time). So far, though I've had no success. The prospective solutions that I've found online can't handle the number of points involved, and produce memory errors. I've tried a couple of methods so far:
- 3D scatter plotting where each plotted point represents one data point from the file, and its colour is controlled by the signal amplitude; and - A slicing method that I found via Matlab code sharing. This used meshgrid to generate a distribution of data across a 3D plane, but could not cope with the number of points to be gridded.
I'm wondering whether the solution lies in the way the data are being managed. Would some approach involving projection of a jpeg onto a 3D surface be more efficient than trying to plot each value from a matrix of 3D data points?
An alternative is to go back to the start, and say "OK. If my data were in a commercial radar format, I could just use dedicated radar processing software. So then how can I flip the file from its current proprietary format to be readable by such a package?" I'll do that if this avenue turns out to be a dead end, but for now I'm looking for a Matlab visualization solution.