1. Vision-Based Expressway Management
Information System
Group-17
Supervised By:
Dr. Ranga Rodrigo
Co Supervised By:
Dr. A.A. Pasqual, Dr. Jayathu Samarawickrama

2. Input
• Low Visibility
• Illumination Changes
• View Point Variation

3. System
License plate localization
Tracking
Logging journey information
ANPR
Anomaly Detection
Data Analysis
Kottawa
Management
Information System
Pinnaduwa

4. Vision Component
Interchange: ENT_Kottawa_01
Plate Id: HC-7153
Color: (230,242,254)
Time: 11/30/2011 08:28:09

5. License Plate
Localization
Post-Processing
& Verification
Plate
Tracking
Plate • Cascaded classifiers using Haar features
Recognition • Training set: 140 positives, 400 negatives
Recall = TP/(TP + FN)
• Recall: ~ 98%
Precision = TP/(TP + FP)
• Precision: ~ 45%

6. License Plate
Localization
Post-Processing
& Verification
Plate
Tracking
• Thresholding and morphology
Plate • Cropping out unwanted regions
Recognition • Line fitting and rotation (view point invariant)

7. License Plate
Localization
Post-Processing
& Verification
Plate
Tracking
Plate • Verification based on plate aspect ratio
Recognition • Recall: ~ 93%
• Precision: ~80%

8. License Plate
Localization
Post-Processing
& Verification
Plate
Tracking
• Find initial license plate center
Plate • Track consecutive plates belong to that center
Recognition • Upon significant displacement in license plate center, initiate next
tracking

9. License Plate
Localization
Post-Processing
& Verification
Plate
Tracking
• Piecewise gamma correction (illumination invariant)
Plate • Separate probabilistic multiclass SVM classifiers for alphabets and digits
Recognition • Majority based algorithm
• Accuracy: ~ 95%

10. Management Information System