MATLAB BASED UNDERWATER AND SATELLITE IMAGE ENHANCEMENT USING AUTO THRESHOLD METHOD

In the field of image processing, Satellite imaging is one of the challenging tasks for the researchers. The different satellite sensors are available in the very low resolution to high resolution range for data collection. In this paper, a satellite image enhancement algorithm based on interpolation of the high-frequency subbands obtained by auto thresholding and the low resolution input image is proposed. This method uses a thresholding and high frequency subband image interpolation into the low resolution input images. The sharpness of image is obtained by the estimation high frequency subband. Inverse thresholding is performed to reconstruct the resultant image. The visual and mathematical results are presented and discussed on LANDSAT 8 data with comparison of proposed method over conventional and state of art resolution enhancement methods. Light scattering and color change are two major sources of distortion for underwater photography. Light scattering is caused by light incident on objects reflected and deflected multiple times by particles present in the water before reaching the camera. This in turn lowers the visibility and contrast of the image captured. Color change corresponds to the varying degrees of attenuation encountered by light traveling in the water with different wavelengths, rendering ambient underwater environments dominated by a bluish tone. No existing underwater processing techniques can handle light scattering and color change distortions suffered by underwater images, and the possible presence of artificial lighting simultaneously.