Seven monochrome video cameras (Table B1) were mounted on the Field Research Facility's 42- m-tall tower (Figure B1) and aimed at the minigrid area.
These cameras were used to monitor wave runup and incident wave dissipation. Runup cameras (R1, R2, and R3) used telephoto lenses for improved spatial
resolution and viewed different regions of the beach. Two dissipation cameras used wider angle lenses for greater spatial coverage of the minigrid area. One
dissipation camera (DS) measured wave breaking over the main cross-shore array of instruments. The other dissipation camera (HU), with a wider field of
view, monitored wave dissipation over a larger region and provided images of bar morphology using time exposures. An infrared camera (IR) was used for
testing nighttime measurements of runup and wave dissipation. A remotely controlled pan-tilt camera (DO) provided additional coverage for special purposes
and served as a backup camera. The camera view angles are shown in Figure B2.
Where:
d = horizontal view angle in degrees
Rmax = maximum range in meters
rx= horizontal cross-shore resolution in meters
ry= horizontal longshore resolution in meters
Fundamental to the video measurements is the transformation between 2D video images and 3D world coordinates, which requires a determination of camera
geometry. This was accomplished with visually identifiable ground control points (GCP's) in the cameras' field of view. The 38 GCP's established during the
experiment consisted primarily of white square signs or highway safety cones painted black and placed on the beach. Coordinates of the GCP's are listed in
Table B2 and shown graphically in Figures B3 and B4. Many of those GCP's were temporary, with a select number positioned on any particular day. A few
instrument pipes and the north property fence posts served as permanent GCP's throughout the experiment.
All video data, with the exception of time exposures, were collected on 12 Super-VHS video cassette recorders. Each VHS tape recorded two continuous
hours, with 4 or 5 runs (8 to 10 hours) collected each day. The collection schedule is listed in Table B3. Several duplicate tapes were made between 16 and 19
October, with times staggered approximately 15 minutes, to ensure data redundancy and to obtain data in the time gaps between video runs. Data runs are
sequentially numbered and include the camera designation. For example, run R101 refers to the first run of camera R1. Video tapes for each run had
near-synchronous start times and a common SMPTE (Society of Motion Picture and Television Engineers) time code recorded on one of the audio tracks. All
DELILAH tapes are in the possession of Dr. Rob Holman and the Coastal Imaging Lab at the Oceanography Department of Oregon State University.
who can be contacted regarding obtaining copies.
Video Time Exposures
Table B4 summarizes the video tape data collected and used to compute the video time exposures. These data were recorded on a Video-8 format VCR. An
example of a daily time exposure is presented below. Other daily images can be viewed by clicking as indicated.
Video Plots and Data Files
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