Analysis of three selected automated multibeam bathymetric filters in BeamWorX AutoClean Software

The increasing volume of bathymetric data acquisition, driven by citizen science initiatives and advancements in hydrographic survey technologies, particularly multibeam and LiDAR sensors, necessitates automated data-cleaning procedures. Manual data cleaning is labour-intensive, subjective, and time-consuming, often requiring two days of processing for a single day of observations. This study evaluates the performance of three widely used automated filters in BeamworX AutoClean software for multibeam bathymetric data cleaning. A multibeam survey was conducted along the jetty of the Nigerian Liquefied Natural Gas (NLNG) facility in Bonny, Rivers State, Nigeria. The acquired bathymetric data were processed using three selected automated filters: BWX Detailed, BWX Spline, and BWX Coarse. Statistical analysis revealed that the BWX Coarse Filter retained 94.45% of the data while rejecting 5.55%, achieving a conformity accuracy of 99.77%. The BWX Detailed Filter accepted 95.84% and rejected 4.16%, with a conformity accuracy of 97.60%. The BWX Spline Filter exhibited the highest footprint accuracy (99.99%) and the highest rejection rate (23.56%), indicating a more conservative approach that may discard valid seabed variations. The results highlight the trade-offs between strict filtering and data completeness. While the BWX Spline Filter ensures maximum accuracy, it significantly reduces data retention. In contrast, the BWX Coarse and Detailed Filters retain more data while maintaining high conformity accuracy, making them more suitable for general seabed mapping. These findings underscore the importance of selecting an appropriate filter based on specific survey requirements, balancing accuracy, noise reduction, and data preservation in hydrographic processing workflows.