The aim of this course is to provide in depth knowledge of the underwater imaging for subsea corrosion inspection. The subsea pipeline corrosion in offshore oil and gas industry is considered as an important problem that further leads to cracks and leakages. Often, the human divers are involved to perform the visual inspection tasks for pipeline integrity management on regular basis. However, the offshore setups are moving from shallow water to deep water due to exhaustion of oil and gas reservoirs. In deep water, the inspection by human divers is inviable due to inhospitable environmental conditions. Due to the reliability of visual inspection method, image based-solutions are found to be effective for deep water inspection activities. However, the underwater image is degraded by low contrast, color attenuation and blurring issues by suspended particles in water. Hence the underwater image enhancement and dehazing operations are required prior to establishing image based-inspection. This course is focused on visual inspection for corrosion estimation using image data. The approach is based on underwater image restoration, with contributions in color and contrast enhancement as well as dehazing for a final application that targets the estimation of the corroded surface of the pipeline.