Bathymetry using an underwater color locus

Abstract

We present a new technique which retrieves water depth (bathymetry) information from an underwater color locus. The underwater color locus contains the range of possible colors which a white object can take for a certain depth range. The color locus model is based on the exponential attenuation of light by the water column and requires a priori knowledge of the water diffuse attenuation coefficients for the site. After employing a camera calibration transform, the experimental and the transformed-simulated loci are shown to coincide in rgz space. The loci confirm the theoretical attenuation of light with depth, indicating a liner decrease in the red color signal and conversely, a linear increase in the green signal with depth. This asserts the potential use of the rg information provided by an underwater color locus for depth estimation.