STUDY ON AN IMAGE ENHANCEMENT FOR SHIP DETECTION USING SYNTHETIC APERTURE RADAR

Abstract

This paper addresses a procedure of an image enhancement for detecting ship in synthetic aperture radar (SAR) imagery. For experiments, RADARSAT-2 covering Ieodo ocean area of Korea was used. In this paper, power law transformation was applied to the radar brightness of original SAR data. This procedure generates a precision image that provides excellent visibility by compensating non-linear response produced by SAR and brings improvement to ship detection performance at final stage. Median and wiener filters with an optimum window size are applied to reduce speckle noise further over the precision image. Adaptive histogram equalization (AHE) are also considered for SAR contrast enhancement. The results were evaluated in terms of the improvement of signal to noise ratio (SNR) and of ship detectability. The results verified that our method is very effective for identifying and detecting ship, particularly for small ship target.ied to the radar brightness of original SAR data. This procedure generates a precision image that provides excellent visibility by compensating non-linear response produced by SAR and brings improvement to ship detection performance at final stage. Median and wiener filters with an optimum window size are applied to reduce speckle noise further over the precision image. Adaptive histogram equalization (AHE) are also considered for SAR contrast enhancement. The results were evaluated in terms of the improvement of signal to noise ratio (SNR) and of ship detectability. The results verified that our method is very effective for identifying and detecting ship, particularly for small ship target.