Teknik Penyisipan Informasi pada Fitur Poligon Peta Vektor Menggunakan Reversible Watermarking

Abstract

Digital vector maps have high precision. Unfortunatelly, watermarking in digital maps usually cause distortion. This study uses a reversible watermarking technique to overcome this issue. The purpose of this study is to apply a reversible watermarking technique to insert some information into digital maps with the ability to restore the map coordinates prior to insertion. In this study, the file used as the insertion media is a 2D digital map coordinate data in shapefiles and images is used as a the watermark. Reversible watermarking process is done on a vector map with polygon features and each insertion process is only performed on a polygon feature. Features that can be inserted should have larger number of vertices than the number of watermark bits. In this study, the watermark is obtained from the MD5 hash function so that the watermark is fixed at 128 bits. The study shows that information can be inserted to the map and that the coordinates can be restored to the initial coordinates. The quality of the map after the insertion shows a low distortion as reflected by the very small RMSE value.