Due to the poor visibility conditions the environment of the world's oceans is still not well explored. The researchers are making use of underwater sequences to monitor marine species, Underwater Mountains & plants. Using underwater images leads to some serious problems when compared to images from a clearer environment. Visibility in an underwater environment is poor, also light is strongly attenuated in water, producing images of low contrast and little color variation. Hence object recognition and segmentation in under water images is a challenging task. After reviewing the broad field of computer vision and current underwater projects, a analysis of histogram based image segmentation techniques are presented in MATLAB using suitable pre image processing and analysis techniques.