Airborne imaging spectrometers have a history of about 20 years starting with the operation of AIS in 1982. During the following years, many other instruments were built and successfully operated, e.g., AVIRIS, CASI, DAIS-7915, and HyMap. Since imaging spectrometers cover a spectral region with a large number of narrow contiguous bands they are able to retrieve the spectral reflectance signature of the Earth's surface allowing tasks such as mineral identification ...
This paper discusses issues related to the use of hyperspectral sensors. Key issues for interpretation are spectral databases of natural backgrounds and military targets as well as the accurate calibration and atmospheric correction. A typical application is presented and future developments are outlined.
A de-shadowing technique is presented for multispectral and hyperspectral imagery over land acquired by satellite / airborne sensors. The method requires a channel in the visible and at least one spectral band in the near-infrared (0.8-1 micrometers) region, but performs much better if bands in the short-wave infrared region (around 1.6 and 2.2 micrometers) are available as well. Five major processing steps are employed : (1) the calculation of the ...
In this paper a wavelet based method for SAR data denoising and compression is presented. An unsupervised stochastic model based approach to image denoising is presented. SAR image is modeled in wavelet domain Gauss Markov Random field and noise is considered as Gaussian with unknown variance. The parameters are estimated from incomplete data using mixtures of wavelet coefficients, and expectation maximization algorithm. The expectation maximization algorithm is used to efficiently ...
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