Transcript Document

Computational Perception
Li Liu
Course
• 10 lectures
• 2 exercises
• 2 labs
• 1 project
• 1 written examination
Scope
Upload information
Computational Perception
Biomedia
Download information
What Do We Study?
• to learn how perceptual organs work
• to understand information processing
under nervous systems
• to experience technical challenges
Perceptual Process
Perceptual Process
Distal
Stimulus
Proximal
stimulus
Sensation
Transduction
processing
Perception
Perception
Recognition
Action
Cognition
Perceptual Cycle
A: The behavior approach
stimulation to perception
B: The physiological approach
stimulus to processing
C: The psychological approach
processing to perception
D: Our approach
Transduction to perception
D
Course Focus
Transduction
processing
Perception
Lec 3 Neuron, neural network, and brain
Lec 5 Learning and neural networks
Lec 4 Natural Sensors
Lec 6
Lec 7
Lec 9
Lec 10
Perceptive field
Sensory integration
Visual attention
Tactile video
Transduction
Transduction is the transform of one form
of energy into another form of energy. In
the nervous system, transduction occurs
when environmental energy is transformed
into electrical energy.
Perceptual Organs
Transduction is the transform of one form
of energy into another form of energy. In
the nervous system, transduction occurs
when environmental energy is transformed
into electrical energy.
Neural Processing
Neural processing is the operations that transform
the electrical signals in the networks of neurons.
An important processing is to extract the primary
sketches from sensory raw data.
Perception
Perception is the
process of putting
inputs together into a
usable mental
representation of the
world.
Right Eye
Left Eye
Retinal Image
Superior
Colliculus (left
lobe)Geniculate
Lateral
Nucleus (LGN) left
Optic Radiations
Visual
Association
Cortex
Optic Nerves
Optic Chiasm
Optic Tracts
Information Rate
Sensory
Bandwidth
sensation
Perceptual
Bandwidth
data
perception
information
Cognitive
Bandwidth
cognition
knowledge
How Do We Study Perception?
This course is to
understand information
processing in the
nervous system.
• computer simulations of
neural circuits, models of
learning,
• representation of sensory
information in neural
networks,
• computational analysis of
problems in biological
sensing and perception
Three Topics
• Learning in neural network
• Interaction bwteen our
neural system and physical
environment
• Sensory integration
How To Do A Project?
Li Liu
Research & Project
” The good researcher is not ’one who
knows the right answers’ but ’one who is
struggling to find out what the right
questions might be’ ”
Phillips and Pugh, 1994
Project
1. Setting your project
2. Conducting your project
3. Presenting your project
1. Setting your project
• Writing a proposal
• Project planning
Writing a project proposal
• Thinking about
Title, aim, objectives, extected
outcomes, related research, questions,
hypotheses,
methods, .....
Project Planning
•
•
•
•
•
•
Work breakdown
Time estimates
Milestone identification
Activity sequencing
Scheduling
Replanning
2. Conducting your project
• Literature searching and
literature reviews
• Doing your project
Literature review
To avoid ”re-invent wheel”
Doing your project
•
•
•
•
•
Project Control
Dealing with problems
Managing your time
Using your supervisor
Team work
3. Presenting your project
• Writing report
• Oral presentation
Ref:
The Essence of Computing Projects
a student’s guide
by Christian W. Dawson
Good luck!
What is a ”project”?
Project = ”Solving a problem”
A Problem?
• What is the problem?
• How to solve the problem?
• How to know that the problem has been solved?
• How good is the solution? A quality measure.
Case 1
Personal Area Network
Principle
Speech – Control Technology
Name Dialing
Hand Free
Speech Recognizer
Speech
Recognizer
”repeat”
Speech Signal Waveform
Effect of Background Noises
Performance
Words Correct Rate (%)
100
0
-30
Speech-to-Noise Ratio (dB)
0
Lip Tracker
Performance of Speech Recognition
Words Correct Rate (%)
100
Auditory and
visual cues
Auditory
cues only
0
-30
Speech-to-Noise Ratio (dB)
0
How to Design A Headset?
Tip ?
Mobile Phones
Scenario
• Shadi has a banking system based on a password
• He heard about an old Palestinian-Chinease
identification system that could increase his
system security
• He made a search on the Internet and found that
he may find it at Umeå University, Biomedia2007.
• You are the consultants to help him
How to enjoy football with
your mobile phone
One way is to use animation..
Live Experience!
Vibration
What is the ball?
What is the ball?
Information Transform!
Control Patterns
Task
To develop and evaluate a touch-based football
broadcasting system for mobile users
iPhone
Virtual Buttons
Real Buttons vs Virtual Buttons
”Entry speed and error rate”
Task
To add the tactile cues of real buttons to virtual
buttons displayed on mobile devices with touch
screens.
Why Do We Study
Perception?
To upload information to our brain!
Direct Interface
Speech Recognizer
Implantable Chips
Neural-Silicon
Interface
Implantable
Computing
Sensory Integration
Resolution of RF
On-Off Perceptive Field
Mathematical Models of
Perceptive Fields
 G ( x, y )  
2
2 πσ
DOG ( σ
σ )
e, i
[
2
1
4
1
2πσ
(2 
x y
σ
exp( 
x
2
2
2
) exp( 
2σ
2
2
2σe
x y
)]  [
1
2 πσ e
2
)
2
exp( 
x
2
2
2σi
)]
Function of
Perceptive Fields
Image Analysis
Neural Information
Transmission
Switch Circuits