Shrnutí

Popis

Terrapoint and LMSI collected LiDAR for over 2,572 square miles in Northumberland, Lancaster, Middlesex, King and Queen, Matthews, Gloucester, James City, Williamsburg, Surry, Isle of Wight, and Suffolk Counties in Virginia. The nominal pulse spacing for this project was no greater than 0.7 meters. This project was collected with a sensor which collects waveform data and provides an intensity value for each discrete pulse extracted from the waveform. GPS Week Time, Intensity, Flightline and echo number attributes were provided for each LiDAR point. Dewberry used proprietary procedures to classify the LAS according to USGS ARRA specifications: 1-Unclassified, 2-Ground, 7-Noise, 9-Water, 10-Ignored Ground due to breakline proximity. Dewberry produced 3D breaklines and combined these with the final LiDAR data to produce seamless hydro flattened DEMs and first return DSMs for the 3,199 tiles (5000 ft x 5000 ft) that cover the project area.