A Process Based Analysis of the 'Shoreline' as Detected in Digital Images

The identification of the 'shoreline' is of fundamental importance to coastal engineers, scientists and managers. Monitoring the 'shoreline' provides vital information for the design of coastal protection and beach nourishment projects, the development of hazard zones, the setting of planning boundaries, the examining of legal property boundaries and for ongoing coastal research and monitoring. With the recent advent of digital image capture and processing technology, continuous and high frequency (hourly to daily) sampling at the coast can now be obtained routinely. A fundamental challenge that remains is to understand the physical nearshore processes (specifically swash and groundwater) that distinguish the visible 'shoreline' within these digital images. In recent years, several techniques have been developed to extract 'shorelines' from images obtained by coastal imaging systems. These image processing techniques separate the land/water interface by identifying contrasting pixel characteristics within the images.