IMAGINE Spectral AnalysisUsers Guide

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Government Reserved Rights. MrSID technology incorporated in the Software was developed in part through a project at the Los Alamos National Laboratory, funded by the U.S. Government, managed under contract by the University of California (University), and is under exclusive commercial license to LizardTech, Inc. It is used under license from LizardTech. MrSID is protected by U.S. Patent No. 5,710,835. Foreign patents pending. The U.S. Government and the University have reserved rights in MrSID technology, including without limitation: (a) The U.S. Government has a non-exclusive, nontransferable, irrevocable, paid-up license to practice or have practiced throughout the world, for or on behalf of the United States, inventions covered by U.S. Patent No. 5,710,835 and has other rights under 35 U.S.C. 200-212 and applicable implementing regulations; (b) If LizardTech's rights in the MrSID Technology terminate during the term of this Agreement, you may continue to use the Software. Any provisions of this license which could reasonably be deemed to do so would then protect the University and/or the U.S. Government; and (c) The University has no obligation to furnish any know-how, technical assistance, or technical data to users of MrSID software and makes no warranty or representation as to the validity of U.S. Patent 5,710,835 nor that the MrSID Software will not infringe any patent or other proprietary right. For further information about these provisions, contact LizardTech, 1008 Western Ave., Suite 200, Seattle, WA 98104.

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Table of Contents / iiiIMAGINE Spectral Analysis

Table of ContentsTable of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii

List of Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi

List of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1

IMAGINE Spectral Analysis . . . . . . . . . . . . . . . . . . . . . . . . . 3Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Algorithms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Task Workflows . . . . . . . . . . . . . . . . . . . . . . . . . . . 4Anomaly Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Target Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Material Mapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Project Wizard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Spectral Analysis Workstation . . . . . . . . . . . . . . . . . . . . 5

Preprocessing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6Sensor Information . . . . . . . . . . . . . . . . . . . . . . . . . . . 6Bad Bands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6Spectral Subset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7Spatial Subset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8Atmospheric Correction . . . . . . . . . . . . . . . . . . . . . . . . 8Minimum Noise Fraction Transform . . . . . . . . . . . . . . . . 8

Tour Guide Examples . . . . . . . . . . . . . . . . . . . . . . . 9Anomaly Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Target Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Material Mapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Material Identification . . . . . . . . . . . . . . . . . . . . . . . . . 9Spectral Workstation . . . . . . . . . . . . . . . . . . . . . . . . . . 9Minimum Noise Fraction . . . . . . . . . . . . . . . . . . . . . . . . 9Atmospheric Adjustment . . . . . . . . . . . . . . . . . . . . . . . 9Additional Tours . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Spectral Analysis Theory . . . . . . . . . . . . . . . . . . . . . . . .11

Hyperspectral Theory . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Imaging Spectroscopy . . . . . . . . . . . . . . . . . . . . . 13

Table of Contents / ivIMAGINE Spectral Analysis

Atmospheric Correction. . . . . . . . . . . . . . . . . . . . 17Atmospheric Modeling . . . . . . . . . . . . . . . . . . . . . . . . . 17Empirical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18Linear Mixing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Endmembers . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Spectrum Libraries . . . . . . . . . . . . . . . . . . . . . . . 21Archive Libraries . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22SITAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22SPECMIN Spectrum Library . . . . . . . . . . . . . . . . . . . . . 22Other Libraries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Algorithms and Metrics . . . . . . . . . . . . . . . . . . . . . . . . . . 25Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Orthogonal Subspace Projection . . . . . . . . . . . . . 25

Constrained Energy Minimization Algorithm . . . . 25

Spectral Angle Mapper . . . . . . . . . . . . . . . . . . . . 27

Spectral Correlation Mapper . . . . . . . . . . . . . . . . 27

Empirical Line . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Flat Field . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Modified Flat Field . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Internal Average Relative Reflectance. . . . . . . . . 29

Log Residuals . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Minimum Noise Fraction . . . . . . . . . . . . . . . . . . . 30

Tour Guides . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Spectral Analysis Workstation . . . . . . . . . . . . . . . . . . . . . 35Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Menus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Edit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37View . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37Help . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Toolbars . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Views . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Libraries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41Archive Libraries . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41Working Libraries . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Spectrum Plot . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Preferences . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

IMAGINE Spectral Analysis Table of Contents / v

Anomaly Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

Before You Begin . . . . . . . . . . . . . . . . . . . . . . . . . 43Simple Anomaly Detection . . . . . . . . . . . . . . . . . . . . 43Bad Band Identification . . . . . . . . . . . . . . . . . . . . . . 43

Simple Anomaly Detection . . . . . . . . . . . . . . . . . . 44Start IMAGINE Spectral Analysis . . . . . . . . . . . . . . . . . 44Choose Input File . . . . . . . . . . . . . . . . . . . . . . . . . . . 45Name Output File . . . . . . . . . . . . . . . . . . . . . . . . . . . 46Compute Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46Analyze ResultsSwipe . . . . . . . . . . . . . . . . . . . . . . . 47Close . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

Bad Band Identification . . . . . . . . . . . . . . . . . . . . 49Choose Input File . . . . . . . . . . . . . . . . . . . . . . . . . . . 49Name Output File . . . . . . . . . . . . . . . . . . . . . . . . . . . 50Identify Bad Bands . . . . . . . . . . . . . . . . . . . . . . . . . . 50Save Band Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55Compute Results . . . . . . . . . . . . . . . . . . . . . .