Spectral Processing

Summary

This extension includes the following Spectral processing capabilities which can be used to perform hyper-spectral and multi-spectral analysis with Opticks:

• An importer to load Landsat TM and Landsat ETM+ files into Opticks.
• The following algorithms to convert an image from radiance to reflectance: Empirical Line Method (ELM) and Internal Average Relative Reflectance (IARR).
• The following algorithms to find signatures matches in an images: Spectral Angle Mapper (SAM) and Constrained Energy Minimization (CEM).
• A specialized "Signature Window" plot to display and manipulate signatures including the ability to generate signatures from a scene (either a single pixel or a user created Area of Interest).
• A specialized "Range Profile" plot to display and then manipulate signatures in order to better align them.
• A number of methods to resample a signature to match the wavelengths of an image before applying a signature matching algorithm.
• The capability to build libraries of many signatures which can then be exported to an ENVI Signature Library file.
• Some additional importers and exporters for both individual signatures and signature sets.
• The Minimum Noise Fraction Algorithm (MNF) in order to preprocess an image and remove extraneous noise in order to improve later signature matching algorithms.

How do I get started with Spectral?

1. Download and install this extension. Learn how to install Opticks extensions.
2. Display the "Spectral" toolbar if it isn't already being displayed. You can do this either using the "Session Explorer" docked window or the "View->Toolbars" menu on the main menu.
3. Look under the "Spectral" toolbar for all of the above mentioned processing algorithms.
4. In general for these algorithms to be beneficial you will need to load hyper-spectral or multi-spectral data and specifically this data should have "Wavelength" information associated with each band. After you load an image, you can go the "Elements" tab of the "Session Explorer" docked window and right-click on the loaded image and select "Properties". On the "Metadata" tab, you should be able to look for "Special/Band" and see one or more of the following: "CenterWavelengths", "StartWavelengths", or "EndWavelengths".

Screenshots and Videos

TBD

Older Releases

Stable Releases
Currently none

Release Candidates

Spectral Processing SDK Downloads

This extension includes it's own SDK that provides static libraries with some utility functions. This can be useful for other extensions to use that wish to leverage some common spectral processing code.