Implications of a new phase function for autonomous underwater imaging

G. R. Fournier; V. Sanjuan-Calzado; C. Trees

doi:10.1117/12.2053878

23 May 2014 Implications of a new phase function for autonomous underwater imaging

G. R. Fournier, V. Sanjuan-Calzado, C. Trees

Proceedings Volume 9111, Ocean Sensing and Monitoring VI; 911119 (2014) https://doi.org/10.1117/12.2053878
Event: SPIE Sensing Technology + Applications, 2014, Baltimore, MD, United States

Abstract

Autonomous underwater vehicles do not have sufficient communications bandwidth over long ranges to send back real time images even for monitoring purposes. Autonomous imaging from underwater vehicles will therefore, require realtime imaging system performance prediction in order to ensure that the vehicle can position itself at a range that will allow it to take an image of the scene or target of interest at the required resolution and contrast level. Ideally the inherent optical properties of the surrounding waters should be measured onboard. This may not be feasible or only a restricted set may be measurable. In order to improve the prediction of the imaging performance, a physics-based analytic phase function that could effectively exploit any a priori or in-situ measured parameters would be extremely helpful. Such a new physics-based analytic phase function has been derived and tested against exact scattering codes. Among other features it is sufficiently precise to allow an accurate determination of the backscatter ratio based on an estimate of the mean index of refraction. The new formulation shows clearly why the backscatter ratio, which is the dominant factor in determining imaging range, is insensitive to the inverse power of the size distribution and almost entirely controlled by the mean index of refraction. This new formulation also has a direct application to improve inverse radiative transfer equation (RTE) modeling for estimating inherent optical properties (total absorption and total backscattering) from measured apparent optical properties (ocean color).

Citation Download Citation

G. R. Fournier, V. Sanjuan-Calzado, and C. Trees "Implications of a new phase function for autonomous underwater imaging", Proc. SPIE 9111, Ocean Sensing and Monitoring VI, 911119 (23 May 2014); https://doi.org/10.1117/12.2053878

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available