Practical use of video imagery in nearshore oceanographic field studies

Mobility of meso-scale morphology on a microtidal ebb delta measured using remote sensing

“…A standard target was placed at a number of locations in the views of each camera and surveyed as temporary ground control points (GCPs). Camera viewing angles were found by comparing the image and survey locations using standard algorithms described in Holland et al (1997). Possible changes in view, when the tower was lowered then raised again in response to thunderstorms or for camera maintenance, were tested for by regularly observing the image locations of a number of identifiable objects such as features on houses or an offshore piling.…”

“…By averaging over shorter wave time scales, clutter was removed leaving an image showing patterns of enhanced wave dissipation that have been shown to correspond well to submerged sand bar or shoreline features (Lippmann and Holman, 1989;Holman et al, 1993;Lippmann et al, 1993;Holland et al, 1997;Holland, 1998;Ruessink, 2003a, 2003b;Plant et al, 2007;Pearre and Puleo, 2009). Since imaging is low cost and can span large areas, time exposure imaging has offered an excellent tool for long-term studies and was the method selected here for exploring the details of ebb-tidal delta morphology.…”

“…3 and converted to world coordinates using standard photogrammetry techniques (Holland et al, 1997). Projections were onto a horizontal surface located at an elevation determined by the tide level at each time of sampling.…”

Rip currents, mega-cusps, and eroding dunes

“…Long-term monitoring of nearshore morphology with high spatial and temporal resolution has become possible with the application of video imaging (Lippmann and Holman, 1990). Video "time stacks" have proven a useful means of examining the evolution of nearshore morphology and rip channels (e.g., Holland et al, 1997;van Ekenvort, 2004). Symonds and Ranasinghe (2000) used an alongshore line of time-averaged pixel intensity within the surf zone to identify rip channels as troughs in the intensity.…”

A review of field methods to survey coastal dunes—experience based on research from South Baltic coast

“…This is a fully automated procedure to derive mainly beach width and elevation changes on video images or movies collected on a daily basis (Holland et al 1997;Uunk et al 2010). In order to obtain quantitative information from these images, several devices must be used.…”