Under water Image preprocessing by Average filter and a comparison study

Underwater image pre-processing is extremely essential because, under water images suffer from quality degradation due to low transmission of light.  When an underwater image is captured, pre-processing is necessary to correct and adjust the image for further  processing. Different filtering techniques are discussed in the literature for pre-processing of underwater images. The filters used normally improve the image quality, suppress the noise, preserves the edges in an image, enhance and smoothen the image. Therefore an effort has been made to evaluate the performance of three filters namely, homomorphic filter, anisotropic diffusion and wavelet denoising by average filter used for under water image pre-processing. Further  studied to identify the suitable filters that process the image to preserve the image quality