Underwater Imaging with Acoustic Lenses: Image Processing and Visualization

摘要

This report discusses image processing, scene reconstruction, and visualizationtechniques used for underwater acoustic images taken with lens-based systems from a stationary platform. These systems are designed for high-resolution imaging of objects from distances of a few meters. The acoustic lenses used for beamforming in the imaging systems are made of crystal polystyrene and are cut in cylindrical or spherical shapes. The cylindrical lens has a fan-shaped beam pattern and produces a 2D intensity image or shadowgram, while the spherical lens with a cone-shaped beam produces a 3D intensity image. Test images obtained by the spherical lens contain a remarkable degree of detail.