The Wonderful World of Electronic Imaging

The Wonderful World of Electronic Imaging

Enrichment Mini-courses Program 2014

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University of Ottawa

How do we see in 3D?How can we reproduce 3D images?

Stereoscopic Imaging

Seeing in 3D• What do we mean by 3D?

• Answer: 3D = three dimensions

• Height

• Width

• Depth

height

width depth

Making 3D Pictures• 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

• 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 Stereoscopiccamera

Stereoscopicdisplay

Viewer(with glasses)

Holmes Wood Stereoscope

Stereocard for a Stereoscope

View-master

Argus Stereo Camera

Viewer

Colonel By Hall

How to display stereoscopic images electronically?

• 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 three-dimensional 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.

LEFTRIGHT

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.• 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 thedisplay

• We use the properties of the cones in the human eye

• We use mathematics to find the best ana-glyph image that will look most like the ideal ste-reoscopic 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

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Make your own stereoscopic image

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 Maker4. 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 HappyColorfulThree-dimensionalSummer!