Off-line HSI Data Analysis and Visualization Tools


		Off-line Sensor Data Processing Tools SCC’s real-time processing software records hyperspectral and high-resolution panchromatic data in formats that can be readily used in off-line processing. As an aid to such processing, SCC has developed tools that read in hyperspectral and panchromatic data and produce geo-registered imagery. These tools have been used by, among others, the US Army Corps of Engineers and the US Environmental Protection Agency.
		The tools can be adapted to numerous HSI data formats. When a tool has been adapted to a data format that corresponds to a particular sensor system, the tool name is modified by appending the sensor system name. For example, GeoReg adapted to the ARCHER data format becomes GeoRegARCHER, and GeoSharpen adapted to the HyCAS data format becomes GeoSharpenHyCAS. The off-line processing tools run in batch mode under either the Unix/Linux or Windows operating system. All required inputs are provided interactively at program initiation. After the necessary inputs are provided, the tools run unattended until all required output files are produced. Thus, they are especially useful for surveying and processing large amounts of collected data.


		GeoSharpen^TM The GeoSharpen^TM tool converts hyperspectral and panchromatic data into high-resolution, geo-registered survey imagery. It takes as its input any or all of the data files collected during a run and produces a series of geo-registered, “pan-sharpened” images. These images have the high resolution of the panchromatic data and color taken from the hyperspectral data. Any three hyperspectral bands can be selected for the RGB channels, and the high-resolution pan data are used to sharpen them. The output files can be in either GeoTIFF format or ENVI™ format at a user-selectable ground projection resolution.
					Small sample of output from SCC's GeoSharpen HSI data visualization tool. Panchromatic data were used for high resolution and three hyperspectral bands were used for color. The data were geo-registered and projected into 20 cm x 20 cm ground pixels. Click image for larger view (547K).

	GeoReg^TM The GeoReg^TM tool accepts HSI or panchromatic data and produces three types of geo-registered outputs: 1. Geo-registered imagery using interpolation; 2. Geo-registered imagery using a nearest-pixel approach; 3. IGM files for ENVI™ users. Program input can be any or all of the HSI data files collected during a run. For output the user can select either all the hyperspectral bands (for analysis) or just three bands (for RGB display). Output can be either 2-byte integers or appropriately-scaled bytes. The former is best for hyperspectral analysis, the latter for display. The output consists of a series of geo-registered files and their corresponding ENVI™ headers for all input files processed, at a user-selectable ground projection resolution.


			Small sample of output from SCC's GeoReg HSI data visualization tool using panchromatic data. The data were geo-registered and projected into 20 cm x 20 cm ground pixels. Click image for larger view (336K).	Small sample of output from SCC's GeoReg HSI data visualization tool, using three of fifty-two available hyperspectral bands. The data were geo-registered and projected into 1 m x 1 m ground pixels. Click image for larger view (476K).

GeoChange^TM The GeoChange^TM tool is a data stream processor that co-registers overlapping HSI datasets and performs pixel-level spectral difference evaluation to detect changes between the datasets. Detected spectral differences are passed to SCC's anomaly detection and signature match detection algorithms. Spectral differences that meet user-defined criteria are declared as targets. GeoChange^TM runs in conjunction with SCC's GeoPaint® HSI visualization window, and provides output to SCC's GeoView^TM target evaluation tool. Some examples of detected changes are shown below.