Extraction of marine debris in the Sea of Japan using high-spatial-resolution satellite images

Abstract

The flow of marine debris in the Sea of Japan causes extensive damage to coastal environments. It is important to understand the debris flow in the ocean for environmental research. The small size of most marine debris in the Sea of Japan makes it impossible to be confirmed directly, even when using high-spatial-resolution satellite imagery. Thus, to extract candidate pixels containing possible marine debris, pixels with spectra that differ from those of the surrounding ocean and wave crests were identified. As a first step towards monitoring marine debris, a previously proposed method for identifying marine debris floating in the Sea of Japan uses a histogram showing the distance from the regression line of the scatter diagram of satellite spectral bands. In this paper, a new method using a spectral angle mapper (SAM) in four- or eight-dimensional space corresponding to satellite spectral bands is proposed. The validity of the method using SAM is also discussed.