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The shadows cast on the object are related to the location of the object relative to the light source.
Take a picture with Light A on. This will cast shadows towards the right side of the image. The height of the shadows reflects the height of the object surfaces
Take a picture with Light B on. This will cast shadows towards the left side of the image.
You can then use image processing to calculate the 3-D shape of the object. This can be used for advanced head tracking, eye tracking, object tracking, and 3-D imaging on cell phones.
The sqwiggles on the bottom was some stuff that I later thought might not be accurate
Hiding in plain sight 