4. Data Classes
Scalar Field
• 1D
• 2D
• 3D
Vector Field
• 1D
• 2D
• 3D
Time Varying
• All of the above
What is a map?
Discrete
• 1D
• K-dimensional
Nominal
• Overlapping sets of data
with multiple nominal
attributes
Graph G = {V,E}
•
•
•
•
Tree
Directed acyclic
Weighted graph
Hyper graph
Ware:Vislab:CCOM
13. Cutoff at 50 cycles/deg.
Receptors: 20 sec of arc
Pooled over larger and larger areas
100 million receptors
1 million fibers to brain
A desktop screen may have 30 pixels/cm
– need about 4 times as much.
I phones better.
VR displays have 5 pixels/cm
14. Aliasing and Anti aliasing
Input pattern
Pixel matrix
Output pattern
15. Temporal Aliasing
Human Flicker fusion 50 Hz
Temporal aliasing occurs with moving
targets
Must compute motion blur to fix the
problem
29. Generic Pre-Attentive Experiment
Number of irrelevant
items varies
Pre-attentive 10 msec
per item or better.
900
700
500
3
6
12
Number of distractors
45. Mapping data to display variables
Data glyphs
Position (2)
Orientation (1)
Size (spatial frequency)
Motion (2)++
Blinking?
Color (3)
Note we have the
problem of heterogeneity
– There is no good
solution
Star glyph
Method