Wiggle stereoscopy is an example of

stereoscopy Stereoscopy, also called stereoscopics or stereo imaging, is a technique for creating or enhancing the depth perception, illusion of depth in an image by means of stereopsis for binocular vision. The word ''stereoscopy'' derives . Any ster ...

in which left and right images of a stereogram are

animated Animation is a filmmaking technique whereby image, still images are manipulated to create Motion picture, moving images. In traditional animation, images are drawn or painted by hand on cel, transparent celluloid sheets to be photographed and e ...

. This technique is also called wiggle 3-D, wobble 3-D, wigglegram, or sometimes Piku-Piku (Japanese for "twitching"). The sense of depth from such images is due to

parallax Parallax is a displacement or difference in the apparent position of an object viewed along two different sightline, lines of sight and is measured by the angle or half-angle of inclination between those two lines. Due to perspective (graphica ...

and to changes to the occlusion of background objects. In contrast to other stereo display techniques, the same image is presented to both eyes.

Advantages and disadvantages

Wiggle stereoscopy offers the advantages that no glasses or special hardware is required; most people can perceive the effect more quickly than when using cross-eyed and parallel viewing techniques. Furthermore, it offers stereo-like depth to people with limited or no vision in one eye. Disadvantages of wiggle stereoscopy are that it does not provide true binocular

depth perception Depth perception is the ability to perceive distance to objects in the world using the visual system and visual perception. It is a major factor in perceiving the world in three dimensions. Depth sensation is the corresponding term for non-hum ...

; it is not suitable for print media, being limited to displays that can alternate between the two images, and it is difficult to appreciate details in images that are constantly in motion.

Number and timing of images

Most wiggle images use only two images, yielding a jerky image. A smoother image can be composed by using several intermediate images and using the left and right images as end images of the image sequence. If intermediate images are not available, approximate images can be computed from the end images using techniques known as ''view interpolation''. The two end images may be displayed for a longer time than the intermediate images to allow inspection of details in the left and right images. Another option for reducing the impression of jerkiness is to reduce the time between the frames of a wiggle image.

3D photos from a single image

With advances in machine learning and computer vision, it is now also possible to recreate this effect using a single monocular image as an input. In this case one can use a segmentation model combined with a depth estimation model to estimate information relating to the distance of the surfaces of objects in the scene from a given viewpoint for every pixel in that image (known as a

depth map In 3D computer graphics and computer vision, a depth map is an Digital image, image or Channel (digital image), image channel that contains information relating to the distance of the Computer representation of surfaces, surfaces of scene objec ...

), and with that information you can then render that pixel data as if it were 3 dimensional to create a subtle 3D effect.

Perception

The sense of depth from wiggle 3-D images is due to

and to changes to the occlusion of background objects. Although wiggle stereoscopy permits the perception of stereoscopic images, it is not a "true" three-dimensional stereoscopic display format in the sense that wiggle stereoscopy does not present the eyes with their own separate view each. The sense of depth may be enhanced by closing one eye, which removes the conflicting

vergence A vergence is the simultaneous movement of both eyes in opposite directions to obtain or maintain single binocular vision. When a creature with binocular vision looks at an object, the eyes must rotate around a vertical axis so that the proj ...

visual cue of both eyes looking at the flat image plane. The apparent stereo effect results from syncing the timing of the wiggle and the amount of parallax to the processing done by the visual cortex. Three or five images with good parallax may produce a better effect than simple left and right images. Wiggling works for the same reason that a transitional pan (or

tracking shot In cinematography, a tracking shot is any shot where the camera follows backward, forward or moves alongside the subject being recorded. Mostly the camera’s position is parallel to the character, creating a sideway motion, tracking the chara ...

) in a film provides good depth information: the visual cortex is able to infer distance information from motion parallax, the relative speed of the perceived motion of different objects on the screen. Many small animals bob their heads to create motion parallax (wiggling) so they can better estimate distance prior to jumping.

Gallery

File:Stereo wiggle 3D.gif, Example of wiggle stereoscopy File:BLUE STEREO 3D Time for Space Wiggle.gif, A wiggle stereogram of the

Sun The Sun is the star at the centre of the Solar System. It is a massive, nearly perfect sphere of hot plasma, heated to incandescence by nuclear fusion reactions in its core, radiating the energy from its surface mainly as visible light a ...

alternating between left and right eye images taken by the

NASA The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the federal government of the United States, US federal government responsible for the United States ...

STEREO Stereophonic sound, commonly shortened to stereo, is a method of sound reproduction that recreates a multi-directional, 3-dimensional audible perspective. This is usually achieved by using two independent audio channels through a configurat ...

solar observation mission File:Home plate anim.gif, Layered rock at the Home Plate plateau on Mars File:WWIScottsEntrenched 3D.gif, World War I stereo view File:The Jinriksha. The chief mode of travel in Japan for Centuries..gif, A jinrikisha in Japan, c. 1901 File:Test of 3-d wiggle for FPC.gif, A wiggle image of a model railroad using 4 frames repeating 1-2-3-4-3-2

References

External links

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Wigglegram
Android application {{Stereoscopy 3D imaging Animation techniques Optical illusions Articles containing video clips Stereoscopic photography