Measuring Hydrology Error on Compressed Terrain
Technical Merit: A quantitative measurement of how well a drainage network captures the hydrology is very important for determining how well terrain simplification technique preserves the hydrology. Past work has been done for comparing how well a computed drainage compares to the real world drainage. Most of the time, real world flow measurements are unavailable and flow simulations have to be used to make predictions (floods, erosion, pollutants, etc). Having a measurement for testing and comparing different models has the potential to be widely used and practical across numerous applications.
Algorithm:
- Compress the Terrain
- Uncompress the Terrain
- Computed the drainage network on the reconstructed terrain
- Map this drainage network on the original DEM
- Take the ratio of the amount of water flowing uphill multiplied by the gradient over amount of water flowing uphill multiplied by the gradient
Details: Please see this paper