Image enhancement method for underwater, ground and satellite images using brightness preserving histogram equalization with maximum entropy

Visibility in an underwater and satellite images is poor, also light is strongly attenuated in water, producing images of low contrast and little color variation. Image preprocessing, smoothing, contrast stretching and restoration technology is concerned with producing and re-establishing an actual array of pixels for object representation to enhance the slow moving raw images. In this paper, an image processing method has been proposed for enhancing various slow motion underwater, ground, and satellite images, taken from underwater submarines and celestial sites. In the suggested method after noise smoothing & contrast stretching, image is equalized for better contrast using histogram equalization (HE), however, it tends to change the mean brightness of the image. So this paper proposes a novel extension of histogram equalization, actually histogram specification, to overcome such drawback as HE, named brightness preserving histogram equalization with maximum entropy (BPHEME), Experimental results show that BPHEME can not only enhance the image effectively, but also preserve the original brightness quite well.