Haze reduction from the visible bands of LANDSAT TM and ETM+ images over a shallow water reef environment

A method for haze reduction in the visible bands of Landsat TM and ETM+ images over a shallow water marine environment is presented in this paper. This method uses the near infrared (NIR) band to estimate the spatial distribution of haze intensity in each visible band through a linear regression model established over deep water areas. As a first order approximation, the signal received at the sensor is assumed to be the arithmetic sum of radiance contributed by haze and the radiance leaving the water surface. Reduction of haze is then carried out by a simple subtraction procedure. Images acquired over the Southern Tip of Palawan, Philippines are used for the experiments. Results show that the method works well for compensating signals contaminated by optically thin haze. Overcorrection occurs when haze is optically thick and geometrically complex. When images are acquired under hazy conditions the method can be applied to drastically improve image interpretability and may also be considered as a necessary pre-processing step for subsequent analyses and information extraction.