Abstract Satellite images may constitute a useful source of information for coastal monitoring as long as it is possible to manage them in an efficient way and to derive precise indicators of the state of the beaches. In the present work, SHOREX system is employed for managing and processing Landsat 8 and Sentinel 2 images to automatically define the instantaneous shoreline position at sub-pixel level. Between the years 2013 and 2017, 91 satellite-derived shorelines (SDS) were assessed by comparing with high-resolution shorelines obtained simultaneously through video-monitoring. The analysis allowed identifying the combination of parameters to perform the extraction algorithm with the highest accuracy. Furthermore, an efficient self-contained workflow is proposed, more robust and independent from inaccuracies in the approximate input line and from multiple morphological and oceanographic issues that may condition the radiometric response near the shore. An iterative procedure ensures firstly a suitable kernel of analysis representing the water-land interface to get, afterward, the definition of the sub-pixel shoreline with high accuracy (below 3 m RMSE).

中文翻译：

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一种从中分辨率卫星图像中准确和大规模定义海岸线的有效协议

摘要 只要能够以有效的方式管理卫星图像并得出海滩状态的精确指标，卫星图像就可以成为沿海监测的有用信息来源。在目前的工作中，SHOREX 系统用于管理和处理 Landsat 8 和 Sentinel 2 图像，以自动定义亚像素级的瞬时海岸线位置。2013 年至 2017 年间，通过与通过视频监控同时获得的高分辨率海岸线进行比较，对 91 条卫星衍生海岸线 (SDS) 进行了评估。该分析允许识别参数组合以执行最准确的提取算法。此外，还提出了一种高效的独立工作流程，更稳健，不受近似输入线的不准确性以及可能影响海岸附近辐射响应的多种形态学和海洋学问题的影响。迭代过程首先确保了一个合适的代表水陆界面的分析内核，然后以高精度（低于 3 m RMSE）获得亚像素海岸线的定义。