Subpixel Classification - this is
a background subtraction process to produce spectral residuals which
represent pure materials. Both spectral and intensity filters are
applied to the residuals. A spectral fit metric is used to identify
the best fractional residual.
Adaptive Signature Kernel (ASK)
- this process refines a spectral signature to account for variations
in the material such as weathering or vegetative state as well as
errors in the atmospheric correction. Child signatures are produced
and compared with the parent in terms of their classification performance
- this process calibrates an image to units of apparent reflectance.
Calibrated reference probe signatures are adapted to the current
image and detected at a subpixel level. Using a technique similar
to ASK, the average correction required to refine the probe signatures
is representative of the atmospheric and sensor contributions to
Spectral Anomaly Finder (SAF)
- this process identifies patterns in residuals to locate specific
spectral variations that are indicative of very small fractional
occurences of materials or changes in the material such as burn
marks or flowers.
Bathymetry - the absorption and scattering
properties of water bodies are modeled and detected to quantify
Water Quality - a four-component model
is used to characterize the chlorophyll, dissolved organic carbon,
suspended mineral, and depth characteristics of a water body. Turbidity
and secchi depth can then be estimated.
BANDS - this process
identifies spectral features within a spectrum using high-order
derivatives and adaptive smoothing to reduce the effects of noise.
Features are characterized by their position, width, and intensity
assuming a superposition of gaussian-like features.
Spectrum Envelop Slope Technique
(SEST) - a new approach to spectral shape matching, SEST
treats a spectrum as a plane curve and matches a signature spectrum
using an intensity envelop coupled with a bandwise slope envelop.
The resulting algorithm is fast, noise resistant, and accurate.
It is suitable for both multispectral and hyperspectral applications.