About my wiggling stereo wiggle (parallax effect in photography)

August 12, 2005; by Igor Polk @ San Francisco Click

I am San Francisco Click
-- Click me to visit my home

 

University of San Francisco

A simple stereo effect can be achieved without any expensive and cumbersome devices like goggles and stereoscopes and any mind bogging technologies. With a computer, a couple of images displayed alternatively can produce a fantastic illusion.

In computer graphics it is called " A cool parallax effect that gives the illustration of depth". See also wiki.

- What is the point?, somebody says. The point is that sometimes a flat photo can not convey the true image of the place. 3D is required. Here is a little collection of 5 photographs which either make no sense in 2D or even give a false impression. Wiggling helps to estimate what is really on the picture: Castle Crags photos.

Here are some of my examples:

Eh?

This effect is quite known at this time.

Jim Gasperini has made wonderful photos utilizing it. His site has quite an impressive collection of links to the resources in this area as well as the area of conventional stereo photography.

I came to the idea quite differently. I never was interested in stereo pictures before. During the work on my interactive virtual tours I was looking at sequences of the similar pictures to find what is the best. To simplify the process I put one image on top of another and then switched windows quickly. I have noticed the effect. Then for unknown to me reason, I fell from the bed some day in July: an idea stroke my head that I have finally to implement it explicitly. I wrote an extension to my java applet and took a test tour. And I like it!

Is this media the same like a movie? I do not think so. Even though the pictures are changing there are only two of them - pictures wiggle, wobble. The stereo effect is achieved with motion. It is clear. After watching the movies I found to myself that moving the camera or moving objects in the foreground or background create the same effect. Yes, our cinematograph is actually using wiggling stereo effect so to speak only on the higher lever.

Nevertheless, photography is not a movie as well as a virtual tour is not a movie either.

I used a regular camera to take the stereo pair pictures instead of a special stereoscopic camera used by other photographers and Jim Gasperini. Since the pictures are taken sequentially with short interval, wiggling unveils some phenomena unknown to the conventional stereo: cars are moving, people walking, flags waving and waves lifting the barges. I consider it a plus, but boy, it is so difficult to take these pictures!

Usually all the small moving objects are unnoticed on a still photo, but wiggle makes them stand out as well as it creates 3D-effect.

* * *

I do not know how mechanisms of the human perception operate, but wiggling definitely works.

It works so well that criticism of the wiggle stereo on Wiki takes way more space than the description of the effect.

Flat computer screens become lighter, cheaper, larger. Very soon all the walls around us will be posted with them. Then the time for wiggling stereo will come. Paper photography will not be forgotten, and movies will develop further, but stereoscopic presentations with wiggling effect will take place on gallery walls and electronic advertisement boards.

Screen savers ask to be implemented with wiggle stereo images.

I believe this will find a lot of application in new computer interfaces to programs and data. Visualization may greatly benefit - first of all to make 2 pictures is much easier than a full fledged animation. But effect is almost the same - I have tried it.

By the way, I have tried to wiggle some stereoscopic pairs I  have found on internet. Some made a perfect pair, some were just awful. Isn't it why my eyes are so tired when I look at the some "true stereoscopic formats" in glasses? Images are just made wrong!

* * *

That is about all I can say now about this dizzying new phenomena. Let us watch for the developments.

Please, let me know what you think.

 

More links:

Jim Gasperini's cluster of sites. Nice photos!
Mars Pathfinder;
Other optical illusions ( not related to wiggle stereo ) ;
Central Pacific Railroad ( only one picture is presented );


From www.adorama.com, an article;

Nature article on "Motion direction, speed and orientation in binocular matching" ( and Russian translation of it where you can see pictures ) ;

Brian David Phillips made quite an extensive research on the topic ;

Wiggle Stereoscopic Viewer applet ;
One more Rover picture;

This thing previously was called "Wobble stereo":
History of the subject and patents

If you want to find more photos on Google, search for "3d wiggle"

 

Questions and Answers:

 
 

Nice photos! But... "Wiggling" is NOT stereo, just as listening to a CD through only ONE speaker is NOT stereo. Just stick with anaglyph or stereo pairs if you want to show true stereo. "Wiggling" is not a stereo format - and is quite annoying. It's important that people are not misled into believing it is stereo. Thanks!
Andalucia
San Francisco, CA USA - Friday, March 10, 2006 at 17:32:50 (CST)

- It is stereo. There are 2 photographs there, and with some adaptation most people can feel the depth. It is much easier to use then a stereoscope, and your eyes will not get sour in 10 minutes. It has exactly the same amount of information as any other stereo pair. In fact, it is better... If it annoys you, you can click S on the keyboard and toggle it off. How can I mislead anyone? They see it with their own eyes. Anyway, thank you for the post. It helped me to improve the site - the information about using S to toggle stereo effect was missed on some pages. Click.

...Continue in the blog

An unknown Wiki-author: "To illustrate the difference between true stereoscopic formats and the two-dimensional "wiggle" method, consider what happens when a [[stereophonic]] music CD is played through only one [[loudspeaker]]: It is no longer possible to hear the stereophonic audio signal since it is now only coming out of one loudspeaker. Flipping between the Left and Right audio channels of the stereophonic signal through the one loudspeaker, the listener is still only hearing a [[monaural]] signal. By listening to the stereophonic music CD through stereophonic [[headphones]] that deliver the proper audio signal to each ear, the listener can experience true stereophonic audio. Similarly, the only way to experience binocular stereoscopic depth perception when viewing stereoscopic images is to use a device (stereoscope, anaglyph glasses, polarized glasses, shutter glasses) that presents each of the two eyes with the corresponding Left or Right image."

Click: Since you started this discussion here, I want to point out to the problems in your logical reasoning. You sound like you assume that stereo sound exists only when stereophonic audio is played through the headphones. Man, you live in an artificial world. In reality, we DO hear audio-spatial distribution of signals scattered around in space. And I want to point out that EVERY ear receives sounds from the same sources. Human brain calculates difference in time when signal reaches receptors through ears, so it is able to find where the source of particular sound is located creating, so to speak, a 3-dimensioal map of surrounding objects. Vision has totally different mechanism. Spatial parallax is calculated for every recognizable part of the visual image, and then brain calculates 3-D map. This map is NOT in eyes. It is inside the brain. It is not what we see, it is the result of "processing". This processing is a mystery yet. Probably when images are delivered inside, as soon as they are taken with the distance from each other, the brain can find a way to assemble 3-D map. It may sound inconvincing, but have you ever tried "flipping between the left and right audio channel through the one head phone?" as you suggested? It probably will not work since time is needed for "flipping" and that offsets difference in time to recognize spatial differences, but it may will produce something. Who knows? On the other hand photo-wiggling does not affect anything. It actually helps to calculate spatial parallax. Time-time in the case with hearing, time-space in the case with sight. See what I mean? Thank you."

 

 

 


Copyrightę2005 Yes San Francisco, LLC. All rights reserved. Copying of images, or their parts, or any other content is prohibited.