Visibility Enhancement of Underwater Hazy Image using Multi-model SVD-DWT Fusion

Abstract

Underwater hazy images (UHI) are inherently dark in nature and are affected by small suspending particles and marine snow.To increase the visibility range and vision depth, an artificial light is utilized.The rays of light are scattered by particles in the underwater medium and along with color attenuation results in problems such as contrast reduction, blurring of an image and color loss driving the images beyond recognition.In absence of any dehazing technique, the performance and usability of a standard enhancement algorithm may fail to produce desirable results.In this paper, we have proposed a novel solution to this problem by proposing fully automated underwater image dehazing using multimodal DWT fusion.Inputs for the combinational image fusion scheme are derived from Singular Value Decomposition (SVD) and Discrete Wavelet Transform (DWT) for contrast enhancement in HSV color space and color constancy using Shades of Gray algorithm respectively.The fused image is then subjected to contrast stretching operation to improve the global contrast and visibility of dark regions.