Mapping of a boundary line from remote sensing: an applied case study on Little Okinawa Island

Abstract

Due to rapid technological improvements, it has become easy to acquire remote-sensing images. Therefore, mapping through remote sensing has become convenient and readily available, which saves time and resources. Nevertheless, some key steps need to be performed during the mapping process, including line generalization and smoothing. The former involves retaining the key characteristics of the original map, whereas the latter removes any unnecessary points; both procedures improve the quality of the final map. Many different theoretical and methodological approaches to smoothing and generalization have been proposed by researchers. In this study, we used the Douglas–Peucker method and Topfer and Pillewizer's law to obtain the optimum threshold length. To achieve this threshold, the following were carried out: (1) small-scale line generalization and (2) line generalization by an intermediate map scale transform. From the line generalization and smoothing process, a boundary line map of Little Okinawa Island was subsequently produced. The results of our study may serve as a valuable tool for future remote-sensing mapping tasks.

Acknowledgements

We thank the reviewers for their constructive comments and suggestions on how this study could be improved. This work was supported in part by grants from NSC 100-2111-M-159-00.