Ambiguous or reversible figures 4

since April 3, 2010



"Ball position reversal illusion"

In the upper image, the left green ball appears to be located in a valley while the right light-blue one appears to be placed on a slope. This relationship is reversed when the image is inverted, as shown in the lower image.

Copyright Akiyoshi Kitaoka 2011 (September 26)


(This idea is not Kitaoka's original)



"Todorovic's depth reversible figure with the Zöllner illsuion"

Two states of wave appearance alternate. One is that the center appears to be convex toward observers while the other is that it appears to be concave. In addition, the six oblique lines are indeed parallel to each other, they appear to tilt alternately.

Copyright Dejan Todorovic 2011 (July 7)



"Illusory cube"

This physically concave object tends to appear to be convex.

Copyright Akiyoshi Kitaoka 2011 (July 1)



the development

high-resolution file



"Depth scission reduces masking of hybrid images"

Copyright Akiyoshi Kitaoka 2011 (June 5)

For Hybrid images: Oliva, A., Torralba, A., and Schyns, P. G. (2006) Hybrid Images. ACM Transactions on Graphics, ACM Siggraph, 25(3), 527-532.







Copyright Akiyoshi Kitaoka 2011 (June 5)


"Blue craters"

The left image appears to be a concave on a bulge, while the right one appears to be a convex in a concave. When this image is inverted, the appearance is exchanged. In addition, the left concave appears to be larger in diameter than the right convex, though they are of the same size.

Moreover, the outer contour of the right image appears to be drawn upper than that of the left one, though they are aligned horizontally. On the other hand, the inner ring of the leftt image appears to be drawn upper than that of the right one, though they are aligned horizontally. <May 8, 2011>

produced by Akiyoshi Kitaoka 2011 (April 23)



This image of sharp edges also works in the same way.






Crater illusion in gray scale



Square crater illusion

produced by Akiyoshi Kitaoka 2011 (May 18)


"Figure-ground reversible image of concentric circles"

In the left image, the outermost ring, the third one and the central circle tend to be figure: i.e. they tend to appear to be in front. Sometimes, for a shorter time, they appear to be ground: i.e. they appear to be located behind the second and fourth rings as a background. The right image shows the upside-down appearance of the left one. In this inverted image, the tendency which appears to be in front is reversed: i.e. the second and fourth rings tend to be figure. This image is adopted from the cover design of a psychology textbook shown below, with permission.

produced by Akiyoshi Kitaoka 2011 (April 21)



Rotation of this book is also fun!



(crater illusion)



In addition

"Position illusion of the figure-ground reversible image of concentric circles"

The leftmost and the third disks appear to be located lower than the rest two, though they are aligned horizontally. I imagine this effect depends on the contrast-dependent size illusion that an image with lower contrast appears to be smaller than another image of the same size with higher contrast.

produced by Akiyoshi Kitaoka 2011 (April 21)



In addition


"Visual phantoms and wriggle illusion of the figure-ground reversible image of concentric circles"

Cross-like oblique gratings of visual phantoms are observed. Moreover, rings appear to wriggle.

Copyright Akiyoshi Kitaoka 2011 (April 21)


"Three heads and six bodies"

There are three heads and three pairs of legs, but six bodies are possible.

Copyright Akiyoshi Kitaoka 2011 February 24)


"One heads and three bodies"

One head can be combined with any of three bodies.

Copyright Akiyoshi Kitaoka 2011 February 25)


"Fivefold tower"

This silhouette appears to be a tower seen from the surface of the ground or appears to be one looked down upon from above.

Copyright Akiyoshi Kitaoka 2011 (January 22)

Thanks to Sam



"Rubic Necker cube"

Perceived depth appears to be flipped over.

Copyright Akiyoshi Kitaoka 2010 (June 4)

Necker cube


Necker, L. A. (1832) Observations on some remarkable Optical Phenomena seen in Switzerland; and on an Optical Phenomenon which occurs on viewing a Figure of a Crystal or geometrical Solid. The London and Edinburgh Philosophical Magazine and Journal of Science 1 (5), 329-337.



"VVV"

"VVV" is sometimes seen.

Copyright Akiyoshi Kitaoka 2010 (April 3)


"Moving Rubin's vase-face illusion"

Copyright Akiyoshi Kitaoka 2009 (August 22)


Ambiguous or reversible figures 3

Ambiguous or reversible figures 2

Ambiguous or reversible figures


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