World View 3 was launched August 13, 2014. In June 2014, the US Department of Commerce gave Digital Globe permission to collect and sell imagery at the best available resolution. WorldView-3 provides 31 cm panchromatic resolution, 1.24 m multispectral resolution, 3.7 m short wave infrared resolution and 30 m CAVIS resolution, making it the highest resolution commercial satellite in the world. The satellite operates at an altitude of 617km and collects 680,000 sq km of data a day.
The following tutorial demonstrates how to orthorectify a WorldView 3 OrthoReady2A image using Geomatica OrthoEngine. OrthoReady 2A data has no topographic relief (DEM) applied with respect to the reference ellipsoid, making it suitable for orthorectification.
1. Open the Geomatica 2015 OrthoEngine application
2. From the OrthoEngine Toolbar click File > New
3. The project Information window opens.
a) Enter a Filename for the project. Browse to your destination folder with the Browse button. Name the project and enter a description.
b) Select Optical Satellite Modelling as the Math Modeling Method
c) Select Rational Functions (Extract from image) under Options
d) Click OK
4. The Set Projection window will open up. Click Cancel to close this window. The projection information will automatically be set once you add your first image.
5. Another pop-up window will appear and click OK.
Open Image Files in OrthoEngine
1. On the OrthoEngine toolbar select Data Input from the Processing Step drop down menu.
2. Select Open a new or existing image.
3. Select the .IMD file associated with the dataset.
GCP and TP Collection
At this stage an Orthorectified image can be directly generated in the absence of any GCPs. The model will be computed based on the supplied RPCs. If GCPs are available, they can be added into the project using the GCP/TP Collection Processing step. The model will be automatically computed, and GCPs can be reviewed through the Residual report. It is recommended to use a ZERO order RPC adjustment if there is a minimum of 1 GCP collected for the imagery. A FIRST order RPC adjustment is recommended if there is a minimum of 3 GCPs. The distribution of these GCPs must be throughout the entire image.
1. On the OrthoEngine toolbar select Ortho Generation from the Processing Step drop down menu.
a) Select Schedule Ortho Generation.
b) Move the image from the Available images window on the left to the Images to process window on the right.
c) Select an appropriate DEM file. For this tutorial gmted2010.pix was selected. This file can be found in the etc folder - C:\PCI Geomatics\Geomatica 2014\etc
d) Modify any of the other parameters based on your data requirements.
e) Select Generate Orthos.
f) The Ortho Production Progress window will show you when the processing is complete.
The final orthorectified image can be viewed in Focus.