Chapter 4: Spontaneous Morphing

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Chapter 4 Spontaneous Morphing

• Heather Oh - Ryan Cho - Jennifer Tam

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Dorsal Simultanagnosia
What exactly is a part?
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• -
• Transversal Intersection
• -at points where the two objects join
  together(intersect)
• Concave creases- sharp edges in the surface that
  point into the object
• Convex creases- sharp edges in the surface that
  point out of the object

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Rule 14. Rule of concave creases Divide shapes
into parts along concave creases. -Any object
may be an example. -Where things seem to join
together. -Where surface degree changes.
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Schroder Staircase
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-Surface Normals -Positive -Negative -Zero
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MOBIUS STRIP
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Main Points -Surface normals and its connection
to concave and convex creases. Where do they
point? -Bubble out of water vs. Bubble inside of
water -What do we really pay attention
to? -Example the mushrooms
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Principal Curvatures Positive, Negative, or zero.
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Figure Ground
If the normals point outward, then the principal
curvature is positive. If the normals point
inward, then the principal curvature is negative.
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When the crease has been smoothed, the crease
turns into a point of high curvature.
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• Subjective and Selective Attention
• -Rule 15. Minima Rule Divide shapes into parts
  at negative minima, along lines of curvature, of
  the principle curvatures.
• -Examples
• Fusilli Pasta
• Keys
• The Ripple

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Ripple
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• Silhouettes
• Rule 16. Minima rule for silhouettes Divide
  silhouettes into parts at concave cusps and
  negative minima of curvature.
• Examples

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Face Goblet
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Similarity
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Symmetry vs. Repetition -Point 1 Repetition
should be easier to recognize because it is the
exact same thing (object or image), just
repeated. (the corresponding parts are always
equally spaced apart) -Point 2 According to
the minima rule, symmetry is easier to see
because the curves repeat at the same point and
the curvatures of the first object match the
second figure.
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Rabbit-Duck
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The minima rule predicts that you should more
easily recognize the objects on the right than on
the left because
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Questions we ask ourselves -What do we notice
more? -What should we divide? Example
Cooking Rule 17 The Salience of a cusp boundary
increases with increasing sharpness of the angle
at the cusp. Rule 18 The salience of a smooth
boundary increases with the magnitude of
normalized curvatures at the boundary.
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Rule 19. Salient boundaries Choose figure and
ground so that figure has the more salient part
boundaries.
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Rule 20 Salient PartsChoose figure and ground
so that figure has the more salient parts.
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The recognizable difference between the figure
and ground of objects is crucial for every day
survival and decision making. Without
understanding simple tasks such as picking up the
butcher knife by the handle as opposed to the
blade, would result in unpleasant consequences.
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Bibliography Hoffman, Dr. Donald D. Visual
Intelligence How we create what we see. 1998.
W.W. Norton and Company, Inc. United States of
America. Jongen, Hubertus Th., Jonker, Peter,
Twilt, Frank. Nonlinear Optimization in Finite
Dimensions Morse Theory, Chebyshev
Approximation, Transversality, Flows, Parametric
Aspects. 2000. Kluwer Academic Publishers.
Netherlands. Also, we used images downloaded
from www.google.com and www.yahoo.com