Study On The Underwater Image Enhancement Using Foreground Model

With the growing population and rapid development of economy,land resources have already can't satisfy people's ever-increasing demand,marine science and technology has increasingly become the focus of the world economy and competition.Up to now,large amount of approaches are proposed to enhance underwater images.The purpose of most approaches either is addressing the color distortion caused by different light attenuation when transmit in the water,or eliminating image blurring caused by the scattering of suspended particles and water.At the same time,some characteristics of algorithm also existed,such as the imaging acquisition equipment is too expensive,requiring a lot of input images and did not consider the particular underwater environment in the processing procedure,so the underwater image enhancement algorithm still needs a further in-depth research.Due to the fact that the light absorbed and scattered by particles in the water in the process of underwater imaging,color distortion and image blurring are caused.The dehazing methods and color correction fail when used in the underwater image enhancement.According to the ideal of removing the color distortion after the image blurring removal,combing with people's perception of underwater images,a new method based on foreground modeling is proposed in this thesis.Due to the attenuation of light in water,a color correction approach that applied to underwater is proposed.The relationship between scattering coefficient and wavelength is used to obtain a more accurate gain estimation for each color channel.In addition,the improved estimation of background light can avoid overexposure in underwater images.In order to evaluate the performance of the proposed approach in this thesis,the results in this thesis is comparing with other methods subjectively and objectively.The experimental results show that the proposed approach can effectively address the problem of image blurring and color distortion,and also the contrast and visibility of underwater images are improved.