Visual Intelligence Chapters 6 & 7. When the World Stopped Moving. 4 th Year Drama and Psych major. Believes she may be quadrichromatic. Tiffany S. Williams. 4 th Year Psych Major Believes Tiffany may be quadrichromatic. Borna Rangchi.
When the World Stopped Moving
Phi Motion (Sigmund Exner; 1875)
Two dots are flashed, one after the other.
With the correct interstimulus interval (time and space between dots), two objects are transformed into one moving object.
If ISI is between a half of a second and a tenth of a second, the illusion of motion is created by your visual intelligence. The precise range of ISIs depends on the distance between dots.
ex. If your visual intelligenceopts to construct one object, it will move across the screen rather than two separate blinking objects.
Curved motions can be constructed when no curve is flashed.
Rule 29: Create the simplest possible motions.
“These motions make two dots merge into one, and leave one dot unmatched. You prefer to conserve objects as much as possible when you construct motion. You don’t want to make two objects magically turn into one, and have another object magically appear, when instead you could just make two objects total, and conserve them over the two frames.”
-(Hoffman pg. 148)
Clockwise or Counterclockwise?
Clockwise or Counterclockwise?
Look off to the side for the full experience.
Dunker was ambitious and decided to add yet another light, this time with one at the hub and one to the wheel…
“motion orthogonal to its lines” – the motion direction you always make for that particular grating.Exploring the Interaction between the Construction of Objects and Motion
You Coordinate your creations of motions and objects by intelligently using size, contrast, depth, and color.
Do u see two independent gratings (combo of 1st and 2nd grating) or one unit?
It means you don’t need that much info to decide whether or not to create a rigid 3D object and its motion. All you need is as little as 3 frames each having 4 points!Um…ok, so how can you do this in practice?
Uh…so what does that mean?
This is advancing the field of computer vision systems. At the moment they are good at constructing 3D objects, but not recognizing them.
Placed lights on joints of actors.
Issue for Rigidity Principle: You can’t have groups of 4 points that move together rigidly.
Knee and ankle points move rigidly, but hip and ankle do not.
You can still construct 3D objects w/o having to create groups of 4 rigid points
This allows us to construct biologicical motion where rigidity alone, does not.
Because of the biological make up of our joints, our bones swing on planes.
Rigidity and Planarity together require only 2 points to construct a 3D object versus the 4 needed with Ullman’s theorem.
Rigidity and Planarity will usually work with other rules too such as rules about smoothness or dynamical constraints
Motion Picture and Gaming: need compelling graphics or people won’t want it.So, you mean there’s more than just the Rigidity Principle? Yup!
Interpreting a smooth diagonal movement along the checkerboard along with the shadow.
When you’re not so bright:
Interpreting a complicated movement of varying elevation and direction just because of a different position of the shadow even though the solid sphere is moving along the same exact path!Dan Kersten and Collaborators.
Shows that we prefer objects of the same color to move together.
“Birds of a feather flock together.”Ooh all the Pretty Colors!
Dr. Hoffman and Dr. Carol Cicerone
Notice how the hand and face are nearby?
The face and arm regions of cortex “invade” the cortex that normally processes the hand.
Proven with magnetic source imaging – a non-surgical process used to measure brain activity. Tony T. Yang (1994)The Somatosensory Cortex