Imaging systems and methods for recovering object visibility

摘要

A system and method are provided for imaging in scattering media such as fog, water and biological tissues. Normally, such images suffer from poor visibility due to backscattering and signal attenuation. At least two images are taken of the scene using active widefield polarized illumination, with different states of a camera-mounted polarizer. The degree of polarization of backscatter is estimated in every point of the scene, leading to an estimation of the backscatter in every point of the scene. A portion or all of the value of backscatter can be deducted in each point of the scene resulting in an enhanced image with improved contrast and brightness range across the field of view.

主权项

1. A fusion imaging method for enhancing object visibility in a scene containing a scattering medium, said method comprising the steps of:
(i) illuminating the scene with an active, widefield illumination system and acquiring a first image of said scene; (ii) acquiring one or more additional images of said scene such that each image is taken with a different illumination position of said scene or with a different camera position or both; and (iii) applying a fusion technique using each image components to obtain an image with enhanced contrast, comprising the steps of:
a. decomposing each image into a Gaussian and a Laplacian pyramid;b. creating a new Laplacian pyramid, in which each level is composed of values from the corresponding level in the Laplacian pyramids of all the images; andc. decoding the final image using the new pyramid.