Transcript Powerpoint slides

University of Ottawa
Enrichment Mini-courses Program 2014
The Wonderful World of Electronic Imaging
Stereoscopic Imaging
How do we see in 3D?
How can we reproduce 3D images?
1
Seeing in 3D
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What do we mean by 3D?
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Answer: 3D = three dimensions
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Height
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Width
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Depth
height
width
depth
Making 3D Pictures
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Over the centuries artists learned to represent the
three-dimensional (3D) world in their pictures using
perspective and other cues.
•
More recently, computer graphics can do the same
thing.
However, the pictures are still FLAT!
Binocular Vision
We see the world with two eyes. Each eye sees a
slightly different view of the scene we’re looking at.
The brain interprets the differences and provides us
with the 3D perception of depth.
Basketball Image
We see with
two eyes
Stereoscopic Imaging
•
Form two images of the scene from slightly different
points of view -- either with a camera or by computer
graphics
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Display the two views with some device that forces the
left eye to only see the left image and the right eye to
only see the right image
A Stereoscopic Imaging
System
Scene
Stereoscopic
camera
Stereoscopic Viewer
(with glasses)
display
Holmes Wood Stereoscope
Stereocard for a Stereoscope
View-master
Argus Stereo Camera
Viewer
Colonel By Hall
How to display stereoscopic
images electronically?
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•
•
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Polarizing filters
Time alternating shutter glasses
Colored glasses (anaglyph)
Lenticular screens
Parallax barriers
Holograms
Polarized stereoscopic display
Time-sequential display
with shuttered glasses
Parallax barrier and lenticular lens
What is ‘anaglyph’?
Anaglyph is a method to view stereoscopic images
using cheap coloured spectacles. It was invented
around 1850. Anaglyph is a Greek word.
The basic idea
For monochrome (no colour) stereo images, the left
view in red is superimposed on the same image with
the right view in blue. When viewed through
spectacles of corresponding colors, the threedimensional effect is perceived.
The Anaglyph stereoscopic images in this
presentation require the red/blue glasses
available in this room to perceive the 3D
effect.
The red filter goes over your LEFT eye.
RIGHT
LEFT
CAUTION
•
It is said that about 10% of people don’t
perceive the stereoscopic 3D effect.
•
Some people may feel queasy when viewing
3D images.
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If you’re in the first group, you may find the 3D
images in the presentation rather boring.
•
If you’re in the 2nd group please don’t feel
obliged to look at the images with the glasses!
Left view
in red
Right view
in blue
Put them
together
3D drawing
Please take your 3D
glasses off
What colors should we use for anaglyph lenses?
Three main types of anaglyph glasses
• Red-cyan
• Green-magenta
• Blue-yellow
More Stereoscopic Images!
On April 17, the National Air and Space Museum premiered Space
Station, a 3-D IMAX film that takes viewers aboard the International
Space Station, orbiting some 220 miles above Earth. Twenty-five
astronauts and cosmonauts from the United States, Canada, Japan,
Russia, and Europe shot more than 12 miles of 65-mm film between
December 1998 and July 2001; Space Station features 3-D sequences
shot during the construction of the ISS, as well as zero-G glides through
the station's interior.
How do we make a color anaglyph?
• We use the properties of the glasses as filters of the
wavelengths of light.
• We use the properties of the light emitted from the
display
• We use the properties of the cones in the human
eye
• We use mathematics to find the best anaglyph
image that will look most like the ideal stereoscopic
image when viewed by a human looking at the
display through the glasses
How do we make a color anaglyph?
More stereoscopic images
https://www.flickr.com/photos/e_dubois/sets/72157606640245479
https://www.flickr.com/groups/anaglyph/
http://adcnj3d.wordpress.com/the-science-of-anaglyph-3d/
Stereoscopic Panoramas
Make your own
stereoscopic image
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Steps to make a stereoscopic
anaglyph
1. Place camera on the slider on a tripod. Take the
left view, slide the slider, then take the right view.
2. Download the two images to the computer.
3. Run StereoPhoto Maker
4. Choose File/open left/right images… and load the
two in that order.
5. Select Adjust/Easy Adjustment …
6. Adjust H position and V position until the preview
looks good with the stereo glasses and click OK.
7. Select Stereo/ Color Anaglyph/Dubois and view.
8. If the result is good, you can save as jpg
Have a Happy
Colorful
Threedimensional
Summer!