chapter 4 recognizing visual object

Question 1

figure

Answer 1

a region of an image that is percieved as being part of an object

Question 2

ground

Answer 2

a region of an image that is percieved as part of the background

Question 3

border ownership

Answer 3

the perception that an edge, or border, is “owned” by a particular region of the retinal image

Question 4

perceptual grouping

Answer 4

the process by which the visual system combines separate regions of the retinal image that “go together” based on similar properties

Question 5

perceptual interpolation

Answer 5

the process by which the visual system fills in hidden edges and surfaces in order to represent the entirety of a partially visible object

Question 6

edge extraction

Answer 6

the process by which the visual system determines the location, orientation, and curvature of edges in the retinal image, based on patterns of responses from neurons in areas V1, V2 and V4 (the “what pathway)

-this is the 1st step in perceptual organization

Question 7

what is perceptual organization?

Answer 7

perceptual organization refers to the visual systems way of dealing with scenes containing multiple overlapping objects. this makes object recognition within complex scenes possible

Question 8

what 3 elements contribute to image clutter during organization into regions?

Answer 8

occlusion, shading and shadows

Question 9

what is uniform connectedness

Answer 9

a characteristic of regions of the retinal image that have approximately uniform properties

Question 10

principles used to assign border ownership and determine figure ground in perceptual organization of a visual scene.

Answer 10

depth, surroundedness (, symmetry (a region with symmetrical borders are mostly figure), convexity (convex borders are mainly figure), meaningfulness( an object has to be distinguished as a figure before it can be recognized as an object with a certain meaning via memory matching ) , simplicity -the number and placement of shapes composing the image

Question 11

describe the step that comes after determining figure ground and assigning border ownership

Answer 11

perceptual grouping- combining image regions into wholes

Question 12

what are the principles of perceptual grouping

Answer 12

proximity, similarity, common motion, symmetry, parallelism, and good continuation

Question 13

define each principle of perceptual group

Answer 13

proximity- elements that are close group more easily
similarity-similar elements tend to group together
common motion- elements that move in unison are likely to be perceptually grouped
symmetry-symmetrical elements tend to group
parallelism- parallel elements tend to group
good continuation-