This PDF file contains the front matter associated with SPIE Proceedings Volume 7812, including the Title Page, Copyright information, Table of Contents, and the Conference Committee listing.

A computed tomographic imaging spectrometer (CTIS) has been developed to allow simultaneous shortwave infrared (SWIR: 1-1.4 μm) spectral imaging and mid-wave infrared (MWIR: 3-5 μm) thermal imaging. The instrument utilizes a mechanically cooled indium antimonide focal plane array which is optically coupled using an Offner relay to a state-of the-art two-dimensional grating. The grating is a computer-generated hologram design fabricated by electron-beam lithography on a convex substrate. The system performs shapshot capture of the spatial and spectral information in a scene, enabling transient events to be characterized. The shortwave spectral information in the higher diffraction orders was reconstructed using existing expectation maximization methodologies while a co-registered thermal image from the zerothorder was analyzed. A co-registered contour map of the shortwave information was displayed superimposed on the thermal image and processed for accurate retrieval of scene knowledge. Spectral accuracy and radiometric test and evaluation results such as noise equivalence temperature difference (NEDT) and minimum resolvable temperature difference (MRTD) are presented for this new spectral imager and a general explanation is given for the theory of its tomographic operation.

Traditional hyperspectral imaging (HSI) sensors are inherently time-sequential during capture, relying upon scanning techniques to construct the resultant hypercube. This temporal constraint hence restricts the use of HSI to static scenes or platforms. The novel sensor outlined within this paper enables snapshot HSI. The Near-Infrared Image Replicating Imaging Spectrometer (N-IRIS) operates without any rejection in polarized light. This prototype has eight SWIR bands and a diagonal FoV of two degrees, with potential for sixteen bands in other infrared regions. Unlike other snapshot techniques, N-IRIS produces a spectral image directly without inversion. Many additional benefits include inherent compactness, robustness, no-moving-parts operation, lower processing overheads and resource needs. Dual polarimetricspectral imaging is also possible due to its inherent design, which offers additional discrimination and higher throughput. HSI algorithms for anomaly detection are prolific in variety, but almost none of them consider the temporal dimension, mainly due to current limitations on speed. This paper describes the results from advanced algorithms implemented on COTS hardware for video-rate operation and designed to exploit the temporal dimension. The synergy with N-IRIS has achieved anomaly detection within streaming HSI hypercubes at video frame-rates. Recorded datasets include static ground scenes with transient targets, while further AVRIS imagery achieved the video-rate detection of embedded simulated targets therein. This new capability through N-IRIS hence broadens the potential application and benefit of HSI sensors to dynamic or transient situations.

The EPA Airborne Spectral Photometric Environmental Collection Technology (ASPECT) Program provides airborne ortho-rectified imagery, video, chemical and now radiological information directly to emergency response personnel via a commercial satellite link onboard the aircraft. EPA initiated the ASPECT Gamma Emergency Mapper GEM Project in 2008 to improve its airborne gamma-screening and mapping capability for monitoring any ground-based gamma contamination. This paper will provide an overview of the system, which can be configured to carry six 2"x4"x16" NaI(Tl) detectors and two 3"x3" LaBr3(Ce) detectors or eight 2"x4"x16" NaI(Tl) detectors. The paper will provide an overview of the analysis of gamma radiation spectra, system limitations, and emergency response applications.

The design and implementation of a compact multiple-image Fourier transform spectrometer (FTS) is presented. Based on the multiple-image FTS originally developed by A. Hirai, the presented device offers significant advantages over his original implementation. Namely, its birefringent nature results in a common-path interferometer which makes the spectrometer insensitive to vibration. Furthermore, it enables the potential of making the instrument ultra-compact, thereby improving the portability of the sensor. The theory of the birefringent FTS is provided, followed by details of its specific embodiment. A laboratory proof of concept of the sensor, designed and developed at the Optical Detection Lab, is also presented. Spectral measurements of laboratory sources are provided, including measurements of light-emitting diodes and gas-discharge lamps. These spectra are verified against a calibrated Ocean Optics USB2000 spectrometer. Other data were collected outdoors, demonstrating the sensor's ability to resolve spectral signatures in standard outdoor lighting and environmental conditions.

The background and beginning of this project have been described in previous SPIE papers^1,2. Since then, atmospheric modeling work on the project has been completed, and the dual-wavelength monolith has been fabricated and fully tested³. The full sodium-wavelength SHIELDS unit was assembled and initially tested with a sodium lamp in 2009, and the project has now turned to that focus in earnest. A full workup with the sodium lamp has been completed, and the unit has started observing a fluorophore target (UV Green) illuminated with both a continuous white-light bulb and with sunlight from the day sky. In both cases, a narrow continuum fringe pattern was observed, but the pattern was too narrow in the spectral direction to extract, as of this writing, the absorption structure necessary to execute Fraunhofer Line Discrimination (FLD). The problem may be an unnecessarily broad sodium line filter. Tests with a narrower line filter in the optical path will be completed in July 2010, and determination of progress and next steps will be made at that time.

A new method is developed for evaluating band selection for detecting gases in hyperspectral images. We use a no-gas background to estimate the sample correlation matrix; we detect anomalies in the gas-present image. After separating the gas and background pixels, we then calculate the SNR. We find that increasing the number of bands tends to lower our overall performance.

We develop new models for the spectral/spatial representation of regions with three-dimensional structure in hyperspectral images. We show that traditional spectral/spatial models lead to ambiguities when classifying these regions due, in part, to changes that occur as the environmental conditions change. The new models characterize the variation of vectors that are derived using spectral/spatial filters as the scene conditions change. These models are compared with multiband generalizations of feature vectors derived from co-occurrence matrices. A feature-selection technique is used to reduce the dimensionality of the model for detection and classification tasks. The utility of several subsets of combined spectral/spatial features is compared for the classification of thousands of forest regions that are generated using DIRSIG over a broad range of conditions.

A multimodal sensor data fusion experiment was performed by exploiting DIRSIG's synthetic data generation capabilities in an urban target detection scenario. Each material in the synthetic scene was attributed with realistic spectral and polarimetric properties, enabling a radiometrically correct calculation of the sensor-reaching-radiance for a notional hyperspectral, multispectral, or polarimetric sensor. The hyperspectral and multispectral data were separately fused with polarimetric data at both the decision and pixel levels, and the impact was assessed by comparing the area under the ROC curves generated by the fused data to the area under the ROC curve generated by the spectral data alone. The impact of additional polarimetric data was shown to be highly dependent on the sensor's viewing geometry, reiterating the complexities involved in polarimetric imaging applications. Also, the impact of additional polarimetric data was demonstrated to depend on the quality of the spatial-spectral information, illustrating the potential to trade spectral resolution for spatial resolution. Further, the decision level fusion algorithm was shown to outperform the pixel level fusion algorithm for the viewing geometries considered, a difference partially explained by the extremely decorrelated nature of the score metrics used as inputs to the decision fusion algorithm.

Accurate statistical models for hyperspectral imaging (HSI) data distribution are useful for many applications. A family of elliptically contoured distribution (ECD) has been investigated to model the unimodal ground cover classes. In this paper we propose to test the elliptical symmetry of real unimodal HSI clutters which will answer the question whether the family of ECD will provide an appropriate model for HSI data. We emphasize that the elliptical symmetry is an inherent feature shared by all ECDs. It is a prerequisite that real HSI clutters must pass these elliptical symmetry tests, so that the family of ECD can be qualified to model these data accurately.

On April 28, 2010, the Environmental Protection Agency's (EPA) Airborne Spectral Photometric Environmental Collection Technology (ASPECT) aircraft was deployed to Gulfport, Mississippi to provide airborne remotely sensed air monitoring and situational awareness data and products in response to the Deepwater Horizon oil rig disaster. The ASPECT aircraft was released from service on August 9, 2010 after having flown over 75 missions that included over 250 hours of flight operation. ASPECT's initial mission responsibility was to provide air quality monitoring (i.e., identification of vapor species) during various oil burning operations. The ASPECT airborne wide-area infrared remote sensing spectral data was used to evaluate the hazard potential of vapors being produced from open water oil burns near the Deepwater Horizon rig site. Other significant remote sensing data products and innovations included the development of an advanced capability to correctly identify, locate, characterize, and quantify surface oil that could reach beaches and wetland areas. This advanced identification product provided the Incident Command an improved capability to locate surface oil in order to improve the effectiveness of oil skimmer vessel recovery efforts directed by the US Coast Guard. This paper discusses the application of infrared spectroscopy and multispectral infrared imagery to address significant issues associated with this national crisis. More specifically, this paper addresses the airborne remote sensing capabilities, technology, and data analysis products developed specifically to optimize the resources and capabilities of the Deepwater Horizon Incident Command structure personnel and their remediation efforts.

A neurodynamical approach to scene segmentation of hyperspectral imagery is investigated based on oscillatory correlation theory. A network of relaxation oscillators, which is based on the Locally Excitatory Globally Inhibitory Oscillator Network (LEGION), is extended to process multiband data and it is implemented to perform unsupervised scene segmentation using both spatial and spectral information. The nonlinear dynamical network is capable of achieving segmentation of objects in a scene by the synchronization of oscillators that receive local excitatory inputs from a collection of local neighbors and desynchronization between oscillators corresponding to different objects. The original LEGION model was designed for single-band imagery. The proposed multiband version of LEGION is implemented such that the connections in the oscillator network receive the spectral pixel vectors in the hyperspectral data as excitatory inputs. Euclidean distances between spectra in local neighborhoods are used as the measure of closeness in the network. The ability of the proposed approach to perform natural and urban scene segmentation for geospatial analysis is assessed. Our approach is tested on two hyperspectral datasets with notably different sensor properties and scene content.

In this paper we address six problems we have encountered when sharpening multi-spectral imagery (MSI) using panchromatic (PAN) images and describe methods we have developed to solve them. We also describe a PANsharpening method that can be used for hyper-spectral data where the PAN-band does not cover all spectral bands. In this paper we compare a number of currently used PAN-sharpening methods. The comparison is done (1) visually creating true and false color composites and (2) compute their radiometric fidelity with the Wang-Bovik quality index.

N-finder algorithm (N-FINDR) is a simplex-based fully abundance constrained technique which is operated on the original data space. This paper presents an approach, convex-cone N-FINDR (CC N-FINDR) which combines N-FINDR with convex cone data obtained from the original data so as to improve the N-FINDR in computational complexity and performance. The same convex cone approach can be also applied to simplex growing algorithm (SGA) to derive a new convex cone-based growing algorithm (CCGA) which also improves the SGA in the same manner as it does for NFINDR. With success in CC N-FINDR and CCGA a similar treatment of using convex cone can be further used to improve any endmember extraction algorithm (EEA). Experimental results are included to demonstrate advantages of the convex cone-based EEAs over EEAs without using convex cone.

Using mathematical techniques recently adapted for the analysis of hyperspectral imaging systems such as the CTIS, we have performed datacube reconstructions for a number of binary star systems. The CTIS images in the visible (420nm to 720nm) wavelength range were obtained in 2001 using the 3.67m Advanced Electro Optical System (AEOS) of the Maui Space Surveillance System (MSSS). These methods used an analytical model of the CTIS to construct an imaging system operator from optical, focal plane array and Computer Generated Holographic (CGH) disperser parameters in the CTIS. We used the adjoint of this operator to construct matched filtered estimates of the datacubes from the image data. In these reconstructions we are able to simultaneously obtain information on the geometry and relative photometry of the binary systems as well as the spectrum for each component of the system.

The Telops Hyper-Cam midwave (InSb 1.5-5.5μm) imaging Fourier-transformspectrometer (IFTS) observed repeated detonations in an ethanol-powered internal combustion (IC) engine. The IC engine is aMegatech Corporation MEG 150 with a 1in. bore, 4in. stroke, and a compression ratio of 3 : 1. The IC combustion cylinder is made from sapphire permitting observation in the visible and infrared. From a distance of 3m, the IFTS imaged the combustion cylinder on a 64×32 pixel array with each pixel covering a 0.1×0.1cm² area. More than 14,000 interferograms were collected at a rate of 16Hz. The maximum optical path difference of the interferograms was 0.017cm corresponding to an unapodized spectral resolution of 36cm^-1. Engine speed was varied between 600-1200RPM to de-correlate the observation time scale from the occurrence of detonations. A method is devised to process the ensemble of interferograms which takes advantage of the DC component so that the time history of the combustion spectrum can be recovered at each pixel location. Preliminary results of this analysis will be presented.

In this paper we discuss our approach to winning entries to the RIT blind test competition. The image cube was preprocessed using a spatial filter that changed the sharpness and enhanced and isolated small point like features. This spatially sharpened cube was then processed using the ENVI hour glass algorithm and obtained high probability of detection and a small probability of false alarm for the blind test targets. In a simulation we quantified this result using metrics related to the Receiver Operator Characteristics (ROC) curve analysis. A hyper-spectral data cube was created and sub-pixel targets were inserted. We found that sharpening the hyper-spectral cube increases the number of correctly identified sub-pixel targets compared to no pre-processing. In particular the simple un-sharp masking filter generates excellent results. We propose that all sub-pixel target detection algorithms could benefit from sharpening of the spectral cube.

The Wildfire Airborne Sensor Program (WASP) is an imaging system designed, built, and operated by the RIT Center for Imaging Science. The system consists of four cameras: a high resolution color camera and SWIR, MWIR, and LWIR cameras. When flown with our corporate partners, Kucera International, the imaging system is combined with a high-resolution LIDAR. This combination provides a full-spectrum, multimodal data collection platform unique to RIT. Under funding by the World Bank, the WASP system was used to image over 250 sq. mi. in Haiti (approximately 15,000 visible and 45,000 infrared frames) from January 21 - 27, 2010 in support of the earthquake relief efforts. Priorities of collection were the area surrounding Port au Prince, the city of Leogane, several other badly damaged towns, and, at the request of the USGS, a high resolution LIDAR collection over the fault line. The imagery was used in the field by disaster relief workers and by collaborators at the University of Buffalo and ImageCat, Inc. to perform building damage and road network trafficability assessments. Additionally, large area mosaics and semi-automatic processing algorithms were developed for value-added product development. In particular, a methodology was developed to extract the locations of blue tarps (indicative of displaced persons) from the images. All imagery was made available to the public through outlets such as Google Earth, the University of Buffalo, the US Geological Survey, the United Nations, and other sites.

Hyperspectral imaging from space requires a very efficient, low f-number optical system to obtain a 20 - 30 m GSD without ground motion compensation. The combination of a folded Schmidt telescope with a Dyson spectrometer meets these requirements while retaining spectral purity. We present the basic design of an instrument that images at f/1.2 with high resolution: with a 300 mm focal length it has a 4 degree field with 20 m GSD and 40 km ground swath from 600 km altitude. Various capabilities, problems, and design options of the Schmidt-Dyson combination are discussed. Detailed design for a specific application remains to be done.

We report progress on a high-performance, long-wavelength infrared hyperspectral imaging system for airborne research. Based on a f/1.25 Dyson spectrometer and 128x128 arsenic doped silicon blocked impurity band array, this system has significantly higher throughput than previous sensors. An agile pointing/scanning capability permits the additional signal to be allocated between increased signal-to-noise and broader area coverage, creating new opportunities to explore LWIR hyperspectral phenomenology.

We describe the optical design and performance of the Next-Generation airborne Imaging Spectrometer (NGIS) currently being constructed at Caltech's Jet Propulsion Laboratory. The new, high-resolution instrument incorporates a number of design advantages including a two-mirror anastigmatic telescope for simplified alignment and high throughput, as well as a concentric, multi-blazed grating for tailored broadband efficiency. A detailed tolerancing and sensitivity approach reveals tight requirements that must be satisfied for spectral calibration and boresight stability. This improved spectral and pointing stability, combined with high uniformity and high signal-to-noise ratio allows us to generate spectrometry measurements capable of answering challenging science questions.

The Portable Remote Imaging Spectrometer (PRISM) is a pushbroom imaging spectrometer currently under development at the Jet Propulsion Laboratory, intended to address the needs of airborne coastal ocean science research. The distinguishing characteristics of the design are high signal to noise ratio, high uniformity of response, and low polarization sensitivity. The optical design is based on the Dyson spectrometer. We discuss here design refinements that are critical for stray light control and for reducing the polarization sensitivity of the entire instrument to below 2%.

In this work we demonstrate the feasibility of using a holographically formed thin film electro-optic stack for the development of an airborne hyperspectral imaging system in the visible wavelength range of 600nm to 800nm. Each wavelength filtering element in the stack is formed by photo-induced phase separation of a homogenous mixture of liquid crystals and photopolymers, exhibiting a uniform reflection efficiency of up to 80% across a 35mm optical aperture with non-normalized baseline transmission, polarization insensitivity for normal incidence and a spectral resolution of 10nm. Fast switching time on the order of microseconds and techniques to improve view angle in the individual wavelength filtering elements in the stack are discussed and the improvements are discussed from a morphological standpoint. Two techniques for stacking the thin films have been developed which requires lesser number of substrates hence improving transmission throughput and radiometric efficiency through the stack. An advantage of using such a stack is the ability to modulate each wavelength filtering element at a different frequency to obtain a spectral multiplex, thereby enabling synchronous detection and demodulation of each wavelength with a high update rate for the hyperspectral cube. A system level integration of such a stack into the prototype drive and detection unit is discussed in this work.

It is of interest to achieve rapid scan rates during airborne spectral collection as spatial blur introduced via platform motion can be minimized. Fourier Transform Infrared Spectrometers (FTS) are well suited to this task. Unfortunately, the trade in an FTS between scan rate and resolution approaches an inverse relationship. An FTS simulation has been developed incorporating multiple instrument and scene parameters to evaluate the system-level trade space. Error sources such as uncertainty in mirror velocity during sampling and jitter are included. A detection metric comprised of multiple common detector algorithms is used to characterize system performance. Results are shown characterizing system performance degradation under a variety of environmental and system performance conditions.

Linear variable filter design and fabrication for LWIR is now commercially available for use in the development of remote sensing systems. The linear variable filter is attached directly to the cold shield of the focal plane array. The resulting compact spectrometer assemblies are completely contained in the Dewar system. This approach eliminates many of the wavelength calibration problems associated with current prism and grating systems and also facilitates the cost effective design and fabrication of aerial sensing systems for specific applications. This paper describes a study that was conducted with the following three objectives: 1) Determine if a multi-channel linear-variable-filter-based line scanner system can be used to discriminate a set of chemical vapors that represent a high probability of occurrence during a typical emergency response chemical incident; 2) Determine which multi-channel linear variable filter design is optimal; and 3) Determine the acceptable instrument noise equivalent spectral radiance for this application. A companion paper describes a separate study that was conducted to determine the concentration levels at which detection and discrimination can be achieved for the various chemicals based on the optimal filter design under various degrees of imperfect atmospheric correction.

Linear variable filter design and fabrication for LWIR is now commercially available for use in the development of airborne reconnaissance or surveillance systems. The linear variable filter is attached directly to the cold shield of the focal plane array. The resulting compact spectrometer assemblies are completely contained in the Dewar system. This approach eliminates many of the wavelength calibration problems associated with current prism and grating systems and also facilitates the cost effective design and fabrication of aerial sensing systems for specific applications. An optimal 32 band linear-variablefilter- based system for detecting and discriminating a set of 11 chemicals representing a high probability of occurrence during a typical emergency response chemical incident was determined in a companion paper entitled "Linear Variable Filter Optimization for Emergency Response Chemical Detection and Discrimination". This paper addresses the effects of atmospheric water vapor on the performance of this optimal 32 band linear-variable-filter-based system. This paper also determines at what increased concentration levels above the optimal system design goal of 30 ppm-m can detection and discrimination of these 11 chemicals be achieved in realistic but imperfect atmospheric water vapor removal scenarios.

Generally, the instrument of color measurement can be divided into spectrophotometer and color meter. The former instrument use prism or grating to separate the light, it can achieve high accuracy but a higher price. The latter instrument use color filter, however there is no spectrum information with it. This article establishes a color measuring system and uses eigen-spectrum method in double light sources to calibrate the spectrum. The measuring system includes tri-stimulus sensors which were made by color filter. The tungsten lamp and Xenon lamp are used to be light source. The advantage of this measuring system is the higher accuracy and the lower cost. The eigen-spectrum method can calibrate the spectrum in less eigenvector. This method used singular value deposition to obtain basis function of spectrum set, which can be obtained by measuring. Because the range of the spectrum set was 380nm to 780nm, the eigenvector per nanometer from 380nm to 780nm can be obtained. In general, the color spectrum can be obtained with less eigenvector. The color difference in L*a*b* color space from 31.2398 down to 2.48841, and reconstructs the spectrum information.