VISUAL PERCEPTION Flashcards
(55 cards)
The process of knowing or being aware of information through the eyes.
Visual Perception
The process of acquiring, interpreting, selecting, and organizing sensory information.
Visual Perception
Applying methods of physics to measuring human perceptual systems.
Psychophysics:
: Understanding how people think. In this context, how it relates to perception.
Cognitive psychology
Visual System:
Light path
Cornea, pupil, lens, retina
Optic nerve, brain
Visual Systems
Retinal Cells
Rods and cones
Unevenly distributed
Generally produced by purpose built cameras, or computer applications, or drawings
Pictures
Some things seem to be done preattentively, without the need for focused attention. Generally take less than ____ msecs (eye movements take _____ msecs)
200-250
200
A ______ _____ represents that visual sensation that allows us to pre-attentively differentiate two adjacent, possibly structured parts in our visual field without eye movement
visual texture
to identify textures, an observations of about ____-____ms is sufficient (cognitively controlled processes require about ___-_____ ms)
160-200
300-400
improve perception of position and orientation
Texture
_____ communicate information about the 3D structure regardless of their coloring
Texture
fundamental micro-structures in generic natural images
-basic elements in pre-attentive visual perception
Textons
Textons can be classified into three general categories:
- elongated blobs
- terminators
- crossings of line segments
_____ believes that only a difference in textons or in their density can be detected pre-attentively
Julesz
When designing textures to indicate different regions of a visualization, make sure that the _____ are as different as possible
textons
Each of these target types can be classified as ___ or ____
friendly or hostile
3D display should provide ___ cues
depth
more distant objects become smaller in the image
can indicate focus, importance, or ordering
- elements of a uniform texture become smaller with distance
Linear Perspective
- show the relative height of objects above a surface
- provide strong depth cues for objects in motion
- can be semi-realistic and still work as a depth cue
Shadow
very powerful depth cue
Occlusion
(structure from motion) –> how objects relate under motion (see next slide for examples)
motion parallax
information visualization displays, one may ____ ____ to emphasize importance, despite depth relationships
exploit focus
Symbols should be rapidly ______ and ______
perceived; differentiated
