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It is generally assumed that oceanic effects, such as absorption, scattering, and turbulence, deteriorate underwater optical imaging and/or signal detection. In this paper, we present an interesting observation that slight turbidity may actually improve the performance of underwater optical imaging in the presence of occlusion. We have carried out simulations and optical experiments in underwater degraded environments to investigate this hypothesis. For simulation, the Monte Carlo method was used to analyze the influence of imaging performance under varying turbidity and occlusion conditions. Additionally, optical experiments were conducted under various turbid and partially occluded environments. We considered the effects of different parameters such as varying turbidity levels, severity of partial occlusion, number of photons, propagation distances, and imaging modality. The simulation results we performed suggest that, regardless of the variation of the imaging system and degradation parameters, slight turbidity may improve underwater imaging performance in occlusion. The optical experimental results are also in agreement with the simulation results that slightly increasing the turbidity levels may boost the image quality in the scenarios we considered. To the best of our knowledge, this is the first report to theoretically analyze and experimentally validate the phenomenon that turbidity may improve underwater imaging performance in certain degraded environments.
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Improving the Visibility of Underwater Video in Turbid Aqueous Environments
Water turbidity is a frequent impediment for achieving satisfactory imaging clarity in underwater video and inhibits the extraction of information concerning the condition of submerged structures. Ports, rivers, lakes, and inland waterways are notoriously difficult spots for camera inspections, in particular for hull inspections in lieu of dry-docking. This complex problem motivated us to study methods to extract a cleaner image /video footage from the acquired one. The purpose of this paper is to describe a novel mathematical model for the degradation of images due to underwater turbidity caused by suspended silt particulates and algae organisms and to propose methods to improve image and video clarity using multiscale non-linear transforms.
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- Award ID(s):
- 1720487
- PAR ID:
- 10293508
- Date Published:
- Journal Name:
- SNAME Maritime Convention
- Page Range / eLocation ID:
- SNAME-SMC-2020-090
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
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