Chapter 6; Space Perception and Binocular Vision

Question 1

Realism

Answer 1

there is a real world to sense

Question 2

positivism

Answer 2

all we really have to go on is the evidence of the senses, so the world might be nothing more than an elaborate hallucination

Question 3

Euclidean

Answer 3

geometry of the world, knowing that things stay consistent: ex: parallel lines will eventually appear to merge. etc.

Question 4

binocular disparity

Answer 4

the differences between the 2 retinal images of the same scene, basis for steropsis, a vivid perception of the 3-D of the world that is not available with monocular vision

Question 5

stereopsis

Answer 5

the ability to use binocular disparity as a cue to depth

Question 6

depth cues

Answer 6

info about the 3-D (depth) of visual space. Both in mono-binocular

Question 7

occlusion

Answer 7

a cue to relative depth order in which, ex; one object obstructs the view of part of another object.

Question 8

nonmetrical depth cue

Answer 8

a depth cue that provides info about the depth order (relative depth), but not magnitude (is nose is in front of his face).

Question 9

metrical depth cue

Answer 9

a depth cue that provides quantitative info about distance in the third dimension

Question 10

projective geometry

Answer 10

the geometry that describes the transformation that occur when the 3-D world is projected on to a 2-D surface. EX: parallel lines do not converge in the real world but they do in the 2-D projection of the world.

Question 11

relative size

Answer 11

comparison of size between items without knowing the absolute size of either one.

Question 12

texture gradient

Answer 12

depth cue based on the geometric fact that items of the same size form smaller images when they are further away. An array of items that change in size smoothly across the image will appear to form a surface tilted in depth

Question 13

relative height

Answer 13

depth cue, the observation that objects at diff distance from the viewer on the ground plane will form images at diff heights in the retinal image. Object farther away will be seen higher in the image.

Question 14

familiar size

Answer 14

a depth cue based on knowledge of the typical size of objects like humans or pennies

Question 15

relative metrical depth cue

Answer 15

a depth cue that could specify, ex: object A is twice as far away as B without providing info about the absolute distance to either A or B.

Question 16

absolute metrical depth cue

Answer 16

a depth cue that provides quantifiable info about distance in the 3-D (exact distance from nose to face).

Question 17

aerial perspective (haze)

Answer 17

foggy/faintness = further away

Question 18

linear perspective

Answer 18

parallel lines in the real world will eventually merge in 2-D image

Question 19

vanishing point

Answer 19

point at which parallel lines will meet in 3-D (vanish)

Question 20

pictorial depth cue

Answer 20

a cue to distance or depth used by artists to depict 3-D depth in 2-D pictures.

Question 21

anamorphosis (anamorphic projection)

Answer 21

use of the rule of linear perspective to create a 2-D image so distorted that it looks correct only when viewed from a certain angle or with a mirror that counters the distortion

Question 22

motion parallax

Answer 22

depth cue that is based on head movement. The geometric info obtained form an eye in 2 different positions at 2 different times is similar to the info from 2 eyes in different position in the head at the same time.

Question 23

accommodation

Answer 23

eyes change it’s focus.

Question 24

convergence

Answer 24

eyes turning inward

Question 25

divergence

Answer 25

eyes turning outward

Question 26

corresponding retinal point

Answer 26

a geometric concept that points on the retina of each eye where the monocular retinal image of a single object are formed are at the same distance from the fovea in each eye. The 2 foveae are also corresponding points.

Question 27

crossed/uncrossed disparity

Answer 27

ex: one image in front of other, crossed = focused on back object, uncrossed = focused on front object.

Question 28

stereoscope

Answer 28

device for simultaneously presenting 1 image to 1 eye and another to the other eye. Differences will give depth.

Question 29

free fusion

Answer 29

the technique of converging (crossing) or diverging the eyes in order to view a stereogram without a stereoscope.

Question 30

stereoblindess

Answer 30

inability to make use of binocular disparity as a depth cue. This term is typically used to describe people with vision in both eyes. Someone who has lost 1 or both eyes.

Question 31

random dot stereogram (RDS)

Answer 31

stereogram made from a large number of randomly placed dots. Random dot stereogram contains no monocular cues to depth. Stimuli visible stereoscopically in random dot stereograms are Cyclopean stimuli.

Question 32

Cyclopean

Answer 32

stimuli that are defined by binocular disparity alone (Random Dot Theory); requires disparity to see difference. Named after 1-eyed cyclops of homer’s odyssey.

Question 33

correspondence problem

Answer 33

in binocular vision, the problem of figuring out which parts of the image goes to which eye.

Question 34

unique constraint

Answer 34

in stereopsis, the observation that a feature in the world is represented exactly once in each retinal image. This constraint simplifies the correspondence problem.

Question 35

continuity constraint

Answer 35

in stereopsis, the observation that, except at the edges of objects, neighboring points int eh world lie at similar distances from the viewer. This is 1 of several constraints that have been proposed to help solve the correspondence problem.

Question 36

binocular rivalry

Answer 36

the competition between the two eyes for control of visual perception, which is evident when completely different stimuli are presented in both eyes.

Question 37

stereoacuity

Answer 37

a measure of the mallets binocular disparity that can generate a sensation of depth.

Question 38

dichoptic

Answer 38

each eye getting a entirely different image/stimuli

Question 39

strabismus

Answer 39

crossed-eye

Question 40

esotropia

Answer 40

crossed-eye; one eye points inward.

Question 41

exotropia

Answer 41

crossed-eye; one eye points outward.

Question 42

supression

Answer 42

the eye that is crossed sees an image it doesnt want.