Kennedy Jim1

7/28/2019 Kennedy Jim1

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Automatic License

Plate Recognition

ACCURACY AND CONFIDENCE

Automatic License

Plate Recognition

ACCURACY AND CONFIDENCE


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What is an ALPR System?

Essentially it is a combination of cameras,illumination and a suite of algorithms thatdelivers the license plate number from apassing vehicle.

Open Road Tolling

Parking Revenue

Stolen Vehicle

Travel Time

Extremely

Very

Somewhat

Not

Very

Forgiveness


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Open Road Tolling

Parking Revenue

Stolen Vehicle

Travel Time

Extremely

Very

Somewhat

Not

Very

Forgiveness

Open Road Tolling

Parking Revenue

Stolen Vehicle

Travel Time

Extremely

Very

Somewhat

Not

Very

Forgiveness


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What is an ALPR System?

Some toll road requirements we encounter:

99.9% image capture

99% overall plate read accuracy

99% OCR accuracy on 90% of capture plateimages number and state

Why is that a problem?

If that isnt enough:

High Vehicle speed

Any light or Time of day

Vehicle Throughput

Read the plate

Report the state


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High Vehicle speed


Vehicle Throughput

Read the plate

Report the state


A car traveling at 75 mph is moving 110 feet/second through the zone


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A car traveling at 120 mph is moving 175 feet/second through the zone



High Vehicle speed


Vehicle Throughput

Read the plate

Report the state


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The shutter must be open long enough to allow enough light in without blurring


The sun provides 10,000 foot-candles of light creating a bloomed out plate image


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High Vehicle speed


Vehicle Throughput

Read the plate

Report the state



High Vehicle speed


Vehicle Throughput

Read the plate

Report the state


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High Vehicle speed


Vehicle Throughput

Read the plate

Report the state



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What is the problem?

About $200,000,000 annual contribution to states.

What is the problem?

About $200,000,000 annual contribution to states.


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How can we possibly comply?

We employ various rules based on all thelicense plate types we expect to encounter

We look for characteristics of the plate thatare unique to a type or state

We look at a signature of the vehicle tocompare it with previous, known vehicles

We compare the read to lists of road usesubscribers or known offenders







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We employ rules


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We employ rules

We employ rules


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We employ rules

CA 98.63%

AZ 0.30%

NV 0.25%

TX 0.09%

All Other States 0.73%

We employ rules

CA 98.63%

AZ 0.30%

NV 0.25%

TX 0.09%



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We employ rules

CA 98.63%

AZ 0.30%

NV 0.25%

TX 0.09%








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We look at plate characteristics

We look at plate characteristics


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We look at vehicle signatures


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We compare to lists

Read as BQL744 Confidence 68Northfield Plaza Lane 4 09:36AM


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We compare to lists


Valid Account List BOL74418 occurrences Northfield PlazaWithin 23 minutes of 09:36AM

We compare to lists


Valid Account List BOL74418 occurrences Northfield PlazaWithin 23 minutes of 09:36AM

Plate Read Corrected to BOL744


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What about Confidence?

Confidence is essentially how certain weare that we have read the plate correctly.

What about Confidence?


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Several things

can affect the

overall confidence

level reported

Syntax

and

location

Known

plates

Plate

features

Vehicle

features

Where to next?

Processor speeds will get faster

Imaging devices will continue to improve

Expectations will grow

License plates will evolve


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Where to next?

Cooperation between States

Cooperation between DMV & Agency

Education by ALPR suppliers

Where to next?





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Where to next?




Where to next?





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www.inexzamir.com

Kennedy Jim1

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