VALIDATION
To verify results obtained from DAS, a still camera, a video camera (25fps), horizontal and
vertical rulers were also employed. The video camera and vertical ruler with 1m height were
used to measure the wave parameters such as wave height, wave frequency and wave period. To
obtain the wavelength, two horizontal rulers with 300mm height, 1m length and meshed in
10mm in vertical and horizontal directions accompanied with the still camera were used. The
wave length was measured by still camera due to its good resolution.
By observing the frame by frame video image taken from wave motion, and counting the number
of frames for two consecutive crests and then dividing that number by 25, the wave period is
obtained. This gave us an accuracy of about one 25th of a second. The wave frequency is then
obtained using the below equation: