Kai: /* Forward-Looking Camera */

2016-10-09T17:55:57Z

Forward-Looking Camera

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=== Visual ===
 
==== Typical Images ====
 
===== Upward-Looking Camera =====
Images from the upward-looking camera are expected to show
* optionally, water surface with ripples
* optionally, human body parts performing swimming or a communication gesture
* optionally, water turbulence
* optionally, scene objects like swim lanes
* optionally, peripheral objects like walls
 

===== Forward-Looking Camera =====
* optionally, walls (in a pool environment)
* optionally, human body parts
* optionally, water turbulence
 

==== Processing ====
===== Background removal =====
The images obtained by the camera could be passed through a low-pass filter to remove the clutter caused by water surface ripples. We could also subtract the background (mostly water surface viewed from below) is to use the Stauffer-Grimson technique based on an adaptive mixture-of-Gaussians model of the background. Theoretically, we can do better than using GMM given domain knowledge: the low-frequency appearance of the water surface can be approximated as a function of the (static) lighting and the motion of the surface according to a wave model. Using a neural network we may be able to learn this function. We would still use a Gaussian mixture model for surface ripples and bubbles, though.
 
 
===== Swimmer detection =====
Strategy #1: Wait until a known, characteristic swimming pose is detected.
 
 

=== Barometric ===

Underwater Data - Revision history

Kai: /* Forward-Looking Camera */