Underwater videos are made with two red laser dots
of fixed separation distance and visible in captured frame. Red
laser dots in captured frame are used for distance resolution
estimation in order to associate statistics with area. This paper
proposes a method for automatic detection of the dots using
wavelet sub-band template matching and laser dot tracking.
Segmentation based on color information and 8-connectivity are
used as preprocessing steps to improve detection accuracy and
optimize computational cycles of template matching stage.
Template matching in the Stationary Wavelet Transform (SWT)
domain is used for further isolating red laser dots. Horizontal
sub-band at 3rd level decomposition using Haar basis function is
used to eliminate unwanted details in template matching. Finally,
a distance error minimization with constrained feature is used in
detecting the red laser dots. This tracking step minimizes the
training requirement of template matching stage whilst
improving detection rate in the undersea video.