computed as a function of just the digital counts of laser return energy at the
sensor, whereas absolute reflectance requires radiometric calibration to convert
laser return energy to radiance. Of the bathymetric LiDAR systems in operation
today, only the SHOALS systems are radiometrically calibrated.
The value of LiDAR-derived bathymetry and seafloor reflectance to coral reef
mapping was discussed in Chaps. 5 and 6. The next section will describe how these
parameters are used in conjunction with additional LiDAR-derived water column
information in the processing of hyperspectral imagery for benthic habitat mapping.
7.2.3 Hyperspectral Color Balancing
Following typical image preprocessing steps of radiometric, geometric, atmospheric and sunglint corrections (see Chap. 4), LiDAR-derived water-leaving
reflectance values can be used to normalize radiometric differences in adjacent
Fig. 7.5 True-color images of CASI-1500 hyperspectral imagery for Hilo Bay, HI: (a) mosaic of
radiometrically and geometrically corrected images; (b) color-balanced mosaic showing the
combined result of path length radiance bias correction, atmospheric correction, sunglint
removal, and color-balancing using the SHOALS LiDAR-derived water-leaving reflectance
7 Integrated LiDAR and Hyperspectral
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