Digital Elevation Model From stereo pair First Experience Naomi Jackson 18-Nov-2013

What is DEM? Digital Elevation Model is a 3-D representation of the terrain’s surface, created from elevation data

What is a Stereo Pair Image? A stereo-pair image contains two views of a scene side by side. One of the views is intended for the left eye and the other for the right eye These images are sometimes viewed with special equipment to direct each eye on to its intended target, but they are also often viewed without equipment.

DEM creation for Sabeto Catchment SOPAC-SPC has purchased Stereo Pair image of Sabeto Catchment Extract terrain parameters cost effective solution

DEM 1:10,000 Soil mapping Agriculture planning for selected areas Modeling water flow and mass movement Water catchment management for areas with high risk of flooding

Example of Stereo Pair Right Image Left Image

Software ERDAS 2013 – LPS TOOL

Method using sample data Mosaic the tiles LPS Project manager tool Create New Block File Model Setup – Relational Function (World View RPC) Block Property Set up – Select Reference Coordinate System Load Stereo Pair - Assign Rational Polynomial Coefficient (Provided with the WV2 Image) Point Process DEM Extraction

LPS project manager

Rational Polynomial Coefficient This file is provided with the World View 2 Satellite imagery Performs Correction – Corrects the Sensor distortion

Quick DEM Extraction DEM extraction (2 steps) the LPS Project Manager toolbar select the DTM Extraction button Select Output Folder

DEM Extraction Tool

Out Put

Challenges Loading imagery Left Image  Right image Corresponding Rational Polynomial Coefficient

Next Steps Image data for Fiji Ground control point establishment New approach to software

Summary DSM production software seems to work

Vinaka