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
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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)
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• 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

DSM production software seems to work