Perception 3 Flashcards
One reason why it’s difficult to design a perceiving machine
Visual input provides ambiguous information about the 3d structure of the world
Another reason why it’s difficult to design a perceiving machine
Image complexity makes it increasingly tricky for computers to organize the visual scene into distinct objects
How do we perceive depth
Humans make use of a variety of sources of image information to infer depth in a visual scene
Relative height is a ___ cue
Monocular
Monocular cues
Work with one eye
Relative size is a ____ cue
Monocular
Occlusion is a ____ cue
Monocular
Linear perspective is a ____ cue
Monocular
Texture gradient is a _____ cue
Monocular
Motion parallax is a ____ cue
Monocular
Shading is a ____ cue
Monocular
Binocular cue
Requires both eyes
Disparity is a ____ cue
Binocular
Relative size and height
Objects below the horizon and have their bases higher are typically perceived as more distant, and two objects of equal size the more distant one will take up less of your field view
We need ______ ______ about relative sizes of objects when judging distance
Prior knowledge
Occlusion
Closer objects will block further away ones
Parallel lines extending away from observer
Converge in the distance
Texture elements get smaller and
More dense with distance
Foreshortening
Circles become ovals; occurs when surface is tilted away
Motion parallax
As we move more distant objects will glide past us more slowly than nearer objects
Shadows create perception of
Depth
Stereoscopic vision
Our eyes each receive a slightly different image
Binocular disparity
Since we have two slightly different images from our each of our eyes, there is a difference in image location
Size of disparity depends on
Object’s depth
Objects closer than the horopter have _____ disparities
Crossed
Objects further than the horopter have _____ disparities
Uncrossed
Structuralism
Proposed that perceptions are simply the sum of atoms of sensation
Gestalt school argued that
The whole form is greater than the sum of its parts
Illusory contours
Some images evoke the perception of edges in locations where there isn’t change in luminance or color
Illusory contours are difficult to explain via
The structuralist approach
Gestalt principles
Proximity, similarity, common fate, good continuation, closure, symmetry
Proximity
Things that are close together group together
Similarity
Things that are similar group together
Common fate
Things that move together group together
Good continuation
Group elements to form smoothly continuing lines rather than abrupt or sharp angles
Closure
Group elements to form complete figures, even if incomplete
Symmetry
Elements more likely to be formed into groups that are balanced or symmetrical
Gestalt principles don’t hold up because
They’re too vague, no evidence
Gestalt principles seem correct such as
Perceptual objects aren’t just sum of their parts and hold across a lot of images
