This document discusses theories of object perception and representation. It contrasts image-based theories that process 2D image templates with structural theories that extract a scene's 3D structure using primitives. Template theories recognize objects based on simple 2D image processing, while structural theories represent objects using 3D geometric components ("geons") and their relationships. The document also describes object displays, which represent structured information pictorially by mapping entities to object parts and relationships to structures. Object displays have been shown to reduce errors in tasks like medical diagnosis. Overall, the document argues that representing objects structurally using 3D components can aid perception and recognition compared to purely 2D image-based approaches.

1. Perceiving and Representing
Structured Information
using Objects

3. Organization



Image based theories
Structural 3D theories
Object perception: Object displays

4. Image Based vs Structure
Theories

Template theories
based on 2D image
processing

In structural theories
we extract the
structure of a scene in
terms of 3D primitives

5. Template theories
A template with simple morphing operations

6. Objects as patterns of (2D)
patterns

10. Scenes (gist in 100 msec)
Torralba and Oliva
Patterns of patterns

11. Properties of Image Recognition




Remarkable image recognition memory
Up to 5 images for second in object
identification
Applications in image searching interfaces
RSVP Rapid serial visual presentation

12. Perception of object structure

13. Geon Theory

14. Geon Theory
3D Primitives “Geons”
Structural skeleton
Shape from shading
is also primitive

15. How Does the Brain Find Geons?
C
ontour
generator

17. Canonical Views
To make things clear
both component parts
and the critical joints
must be clear

18. Processing stages for recognition

19. The Geon Diagram Pourang Irani


3D shape primitives for architecture
- entities and relationships
Surface texture and color for
attributes

20. Pattern finding
& Recognition
13% errors: 4.3 sec
sub-structure
22% memory
errors
26% errors 7.1 sec
sub-structure
42% memory
errors

21. Semantics




On top of - relies on
Underneath – support, foundation
Inside – containment (private code)
Attachment points (external interfaces; part_of
relationships) more than topology



mid
Upper
Lower

22. Natural semantics
Instances
Strength of Relationship
Dependency
Multiplicity

25. The Object Display (Wickens)





Use complex objects to fuse variables
Map entities to object parts
Map structure to object structure
Can be pictorial (simplified) – an engine +
fuel tank
Map attributes to object attributes
- color, size, motion etc.

26. Object Display
Vol : 45 L
Temp: 45 deg
Flow: 20%
Solids: 23%
100 L
45 L
45 deg
Solids: 23%
0.2/1.0

27. Approx 1/3 errors with
anesthiologists
Dr George Blike

28. 

A medical
ventilator
Such displays
Must be custom

29. Chart Junk (ducks) Tufte
or Effective Communication
1990
2000
2010
1990
2000
2010

30. A Duck? (Tufte)

32. The concrete/abstraction tradeoff




Object displays may lead to lower errors
Lend themselves to overly literal interpretation.
They are not general purpose.
Object displays must be custom designed
More abstract representations leave more room
for interpretation (better support the creative
process)

33. 2 ½ D design


Use 3D objects to represent entities
Layout to make structure clear in 2D.


-Connections, basic shapes
Use canonical views

34. Holding attention
-Object scene conflict
Used in advertising

35. Emotional and motivational
effects

36. Conclusion


There is a great future in 3D object icons
and object structures
It is happening anyway, but nice to know
that it is not always “chart junk”.

37. Conclusions



Visual space is non-homogenous
The plane orthogonal to the line of sight
and the forward direction are very
different.
1
A 2 /2D design attitude recognizes the cost
of actions.

38. 3D versus 2D
11.4% errors 3.7 sec
sub-structure
20% memory
errors
21% errors 5.1 sec
sub-structure
34% memory
errors