Underwater Image Quality Enhancement Methods and Problems: A Review

Underwater environments generally cause color cast or color scatter while photography. Color scatter is due to haze effects appearing when light reflected from thing which absorbed or may be scattered several times by particles of water. This cause lowers the visibility and less contrast of the image. Color cast is due to the varying attenuation of light in various wavelengths, and this is cause underwater environments bluish. To mention distortion from color scatter and color cast, this paper proposes a method to reconstruct underwater images that which is a combination of a wavelength compensation and de-hazing algorithm (IDWC). One has to determine the distance between the objects and the camera using dark channel prior, then haze effects cause by color scatter can be removed by the de-hazing algorithm. Next, one has to estimation the photography scene depth using residual energy ratios for each. According to the attenuation of every wavelength, reverse compensation conducted to restore all distortion from color cast.