To extract this information the proposal follows a concept similar to color vision of the human eye. Analog to the three types of color receptors of the eye four spectral channels are defined for the SWIR. Each point of the image is attributed now by four “color values” instead of a single gray level. For a comprehensive characterization of an object, a special SWIR colorimetry is possible by selecting appropriate filters with suitable band width and spectral overlap. The spectral sensitivity, the algorithms for calculating SWIR-color values, the discrimination of SWIR-color values by Noise Equivalent Wavelength Difference (NEWD) and spectral coded false color image display is discussed and first results with an existing SWIR camera are presented. |
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