High resolution video cameras are mounted on the top of the 43 m tall (141 ft)
FRF observation Tower.
C1 faces N, C2 faces NNE, C3 faces NE, C4 faces E (offshore), C5 faces SE, and C6 faces S.
Each image has GCP's (ground control points) which
are used to determine the camera's orientation relative to the ground topography. The most
noticeable GCP's are three disks from camera C0.
These GCP's allow for a photogrammetric transformations of image coordinates to ground coordinates.
Thus, time sequences of these images can be used to monitor changes in sand bar morphology
or shoreline position and potentially other variables. Also, these cameras are used to
collect data on horizontal distributions of wave-breaking and shoreline movement.
One application of these systems is the imaging of the sandbar location as it effects wave
breaking.
Each camera takes a snapshot (*snap.jpg) and a 10 minute time-averaged image (*timex.jpg) every hour. Timex
are created by averaging 700 frames taken once per second. These images are useful at revealing the underlying
morphology as waves break over the submerged sandbars. The 10 minute averaging serves to smooth out variations
in wave dissipation (white water) due to wave groups.
File names contain the date, time, camera, and image type information. These file names come in two formats,
a "long" name and a "very long" name. For example:
- "10Aug2001_1120EST_c2_timex.jpg" is a timex image from camera c2 on 10 Aug 2001 at 1120 EST.
- "997442437.Fri.Aug.10_16_20_36.GMT.2001.argus02a.c2.timex.jpg"     is the same image with the time (16:20:36) listed
as GMT (5 hours ahead of EST), the first number indicates the epoch time, and argus02a identifies the Duck Argus station.
This video technique was developed by Dr. Rob Holman of
the Coastal Imaging Lab in the
Oceanography Department of Oregon State University. Mr. Kent Hathaway is the FRF
video expert.
Historical archives are here (1986-1998) ...
See new Lido Key Mini ARGUS images here.
See new Sunset Beach Mini ARGUS images here.
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