Casey SmithDoug RitchieFred Lloyd

Michael Geary

School of Electrical and Computer Engineering

November 2, 2011

ECE 4007

Automated Speed Enforcement Using a Digital

Imaging System

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Project OverviewProject Overview

• A prototype speed enforcement system which processes images captured by multiple cameras to determine remote controlled car speed and locate license plates

– Improve roadway safety while producing revenue for governments which choose to deploy them

– Potential customers of the finished product include local, state, and federal law enforcement officials

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Design ObjectivesDesign Objectives

• System– Software will determine car speed and isolate the

license plate

• Accuracy– Detect car speed within 1 mile per hour

• Cost– Complete prototype for under $405.00

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Design IllustrationDesign Illustration

Camera Control and Image Acquisition

Motion Detection

Speed Detection

License Plate Location

Software Overview

No Motion Detected

Motion Detected Once

Motion Detected Twice

Above 5 mph

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Image AcquisitionImage Acquisition

• Most critical component of ASED

• Acquires two images every 500ms– Left/Right camera

• Dynamic image filename structure for data storage and later processing

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Image Acquisition: DemoImage Acquisition: Demo

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Motion Detection: Input ImagesMotion Detection: Input Images

Input Images before manipulation

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Motion Detection: Image Comparison and ThresholdingMotion Detection: Image Comparison and Thresholding

Subtracted Image Image After Thresholding

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Motion Detection: Erosion and DilationMotion Detection: Erosion and Dilation

Erosion

Dilation

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Motion Detection: Noise ReductionMotion Detection: Noise Reduction

Noise Reduced Image Masked Image

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Speed Detection: RC Car Distance ComputationSpeed Detection: RC Car Distance Computation• Stereo Vision Triangulation

Image courtesy of NI Developer Zone at http://zone.ni.com/devzone/cda/tut/p/id/8176

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Speed Detection: Determining RC Car SpeedSpeed Detection: Determining RC Car Speed• Triangulation performed at times t and t + 500ms

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License Plate Location: Reflection RemovalLicense Plate Location: Reflection Removal

Image With Reflection Image After Correction

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License Plate Location License Plate Location

Original License Plate Processed License Plate

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Camera Only Design ApproachCamera Only Design Approach

Advantages

•Easy to interface with a computer for processing

•No need to interface several physical detection devices

Disadvantages

•More coding compared to other methods

•More calculation required for speed detection via triangulation

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Project CostsProject Costs

• There are few costs associated with this design as LabVIEW and the required camera were provided free of charge by Georgia Tech.

– Rolling cart: $90

– Remote controlled car: $60

– Total current cost: $150

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Project DemonstrationProject Demonstration

• Place clear distance marks in the test area by which hand speed calculations can be done

• Run the car once in the test area above the set speed limit

• Run the car once in the test area below the set speed limit

• To be considered successful the ASED must correctly detect weather or not the car is speeding and locate the license plate of the speeding car.

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Project TimelineProject Timeline

• (10/07) - Write image acquisition code• (10/14) - Write motion detection code• (11/18) - Write speed detection code• (11/18) - Write license plate location code• (11/25) - Modify code segments to work together• (12/02) - Testing and debugging• (12/16) - Final project presentation

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Issues with DesignIssues with Design

• Compatibility between LabVIEW 2009 and the Bumblebee XB3 camera

• Converting pixel distances to real-world distances for speed detection

• Finding a license plate within a given image

• Interfaces between code segments

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QuestionsQuestions

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Speed Detection: Trigonometric FunctionsSpeed Detection: Trigonometric Functions

Law Of Sines Law Of Cosines

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Speed Detection: Triangulation DetailsSpeed Detection: Triangulation Details

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Speed Detection: Triangulation Details ContinuedSpeed Detection: Triangulation Details Continued

Known: D1, D2, b Unknown: H, g, c, I, k, d

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Speed Detection: Alternatives Speed Detection: Alternatives

• Quickbird– Earth observation satellite– Object based vehicle extraction

• VASCAR – Combines stopwatch with computer– Two measurement spots on road

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License Plate Location : ROI LocationLicense Plate Location : ROI Location

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Optical Character Recognition Optical Character Recognition

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Alternative Speed Detection DevicesAlternative Speed Detection Devices

Pneumatic road tubes Infrared Sensors

Radar Gun LiDAR