15
Stereo Vision
adapted from Magic Eye, Inc. and Rachel Cooper.
Unlike horses, humans have two eyes located side-by-side in the front of their
heads. Thanks to the close side-by-side positioning, each eye takes a view of the
same area from a slightly different angle. The two eye
views have plenty in common, but each eye picks up
visual information the other doesn't.
Each eye captures its own view and the two separate
images are sent to the brain for processing. When the
two images arrive simultaneously in the back of the
brain, they are combined into one picture. The brain
combines the two images by matching up the
similarities and adding in the small differences. The
small differences between the two images add up to a
big difference in the final picture! The combined image
is more than the sum of its parts. It is a three-
dimensional
stereo
picture.
The word "stereo" comes from the Greek word
"stereos" which means firm or solid. With stereo vision you see an object as solid
in three spatial dimensions--width, height and depth--or x, y and z. It is the added
perception of the depth dimension that makes stereo vision so rich and special.
How iZ3D displays stereo images
In order to make observer see 3d scenes on the screen of iZ3D, we show
different pictures to each of the eyes– pictures of the same objects but shot from
different viewpoints. As a result, in iZ3D glasses, the left eye sees images
rendered by the left camera and the right eye sees image rendered by the right
camera.
The cube is drawn on the same
position for both eyes, therefore
to observer it will seem to be
situated right in the iZ3D screen
plane.
The ball is drawn with positive
parallax – in right eye it is
drawn to the right from its
image in the left eye – therefore
the ball will seem to be deep
inside the display.
The pyramid is drawn with
negative parallax – in the right
eye it is drawn to the left from its image in the left eye – so the pyramid will seem
to be floating in front of the iZ3D.
iZ3D Screen