Research On The Island Extraction Using Remote Sensing Images

China is covered with immense ocean areas, and holds a large quantity of islands which arescattered in various sea space around our country. How to rapidly derive the quantity,distribution,position and shape is a crucial issue. The development of remote sensing makes therapid extraction of islands by making use of RS images possible.This dissertation aims at research on how to extract the island rapidly and effectively fromimages. Main contents and innovations are as follows:1. Basic theories in the extraction of edges on region feature are summarized, andthreshold method, sectional incremental method, edge extraction and active contour modelmethod are analyzed.2. After analyzing the feature of the island RS images, a method based onQuadtrees-GACM are proposed. Aiming at the complicated sea surface in the sea area, a methodbased on Geometric active contours model which can automatically get the initial contour. Experimentalresult proved that island boundary can be extracted effectively and stably by this method.3. Mean shift algorithm is introduced into the extraction island combined with theabundant color information of RGB images. Combined with relatively good connectivity of seaarea, a modified Mean shift island extraction method has been proposed which is based on pixellabelled. Experiment proves that this method has benign anti-noise attribute and rapid extractionof island can be achieved.4. The post processing and expression of island extraction result are researched .Aiming atwiping off the"ship, cloud, wave"information in the island extraction result, two methods areproposed by making use of multi-temporal RS images and the condition of multi attributeconstraints, and the feasibility of two methods were proved. The boundary of island is vectorized,the data compression is researched.5. Island extraction system is designed. Island extraction is implemented manually andsemi automatically. The input and output of vector data is shapefile format. The island area andits coastline length are computed automatically. And rapid watch image of island is formed, sothat the result is convenient to inspect.