visual perception Flashcards
what does gestualt perception of form study
human vision is biased to look for structure and chooses the simplest interpretation of an image
what are gestault principles and what do they show
laws of human perception; find order, recognise groups, simplify complex images
emergence
seeing the whole picture
proximity
object closer together are perceived as a group
closure
you can still see the complete shape even when some parts arent visible
continuity
grouping a series of elements when they follow the same path
similarity
group together objects that share visual features
common region
objects in the same region are grouped together as one
figure/ground
images are seperated into the foreground and background in order to simplify them with more attention given to the foreground
what is the benefit of visual structure and what can reduce search time
helps us scan and understand information quicker
spacing grouping and alignment can reduce search time
pre-attentive processing
we are able to perceive something without using our eyes to focus on it
what makes an action pre-attentive
when information is gained in less than 200 - 250 ms (less time than we would need to move our eyes)
pop out features (pre-attentive features)
visible features that have the ability to draw our attention
what are some criteria for pop out features
they must be different from everything around them
colour is usually better than shape
what is the point of attention guidance and how do we do it
done through pre-attentive processing
directs our attention to critical information
conveys information at a glance
what are the 3 types of visualisation data
categorical; variables with named attributes
ordinal; possible values have a logical order
quantitative; variables have a magnitude
what do perceptual channels do and what are the two types
represent data visually
position
colour hue value
how is position a good perceptual channel
effective for conveying information
highly expressive
encodes quantitative variables
colour hue and value as a perceptual channel
value is perceived as ordered (light to dark)
hue; good for categories as its disctint
less good for continuous variables as were better at seeing contrast
why do combined features not count as pop out features
they need more search time
