570 likes | 869 Vues
Autoscope Basic Concepts Introduction & Online Resources 20 March 2014. Presented by:. Headquarters: 3360 E. La Palma Ave Anaheim, CA 92806 USA 714 630-3700. Autoscope ® Vehicle Detection since 1984 In 2014, celebrating 23 year partnership with Image Sensing Systems (ISS).
E N D
Autoscope Basic ConceptsIntroduction & Online Resources20 March 2014
Presented by: Headquarters: 3360 E. La Palma AveAnaheim, CA 92806 USA714 630-3700
Autoscope® Vehicle Detection since 1984In 2014, celebrating 23 year partnership with Image Sensing Systems (ISS)
Section Purpose • Autoscope® Basic Concepts • The fundamentals of “thinking” video detection • Review video detection fundamentals • Why Detection? • How video detection Work? • Raw detection event from video “snapshots” • Validating the detection event we want • What we do with each detection event • Example Fields-of-View • Occlusion… cross street, cross lane, down lane, & obstruction
Autoscope® Basic Concepts Why Detection?
Why Detection? • Detection: • Increases the capacity of our roadways • Provides information about demand for service at an intersection • Efficient & Safe Operations • Effective movement of people • Successful resource for community • Provides the information foundation for modern traffic management systems
All Traffic Problems are Local • Traffic Congestion • Red Light Violations • Equipment Failures • Lack of Signal Coordination • High Maintenance Costs, Deferred Tasks • Manufacturer Support? Econolite! • Equipment Limitations for Traffic Demand • Expansion of Traffic System, Add Signals • Training: New Technologies, Concepts, … * Other Local Traffic Problems …
Traffic Congestion Affects … • The Public • Government Ministries & Departments • Businesses • Everyone feels the impact of traffic congestion. * We all get frustrated with traffic congestion
Traffic Management Benefits … • The Public • Government Ministries & Departments • Businesses • Everyone feels good when we keep people moving. * We all want to be mobile
Autoscope® Basic Concepts How Does Video Detection Work?
How Does Video Detection Work? Our class goals: • Video Detection Concepts • How Does It Work? • What Can It Do? • Types of Applications • Limitations • Language of Video Detection • Configuring an intersection application * The Basics
First, Some Background • Video Detection • How it works • What it can do • Where to use it
How Does Video Detection Work? • How Does It Work? • Video Detection Concepts * The Basics—How it works 2
What is video detection? • Process video pictures • Test for a valid event • Output call or data or video • Repeat with consistency * Video detection technology in a nutshell
1. Process Video Pictures • Process live analog video signal • Find differences between images • Repeat for 30 frames per second * To human eye, a “movie” appears continuous
1a. ForEach Video Frame • Digitize picture • Divide picture into pixels • Rows & Columns • Capture informationabout each pixel • Repeat 30 times per second * Converts picture to raw data 1100110000111010101000101010
1b. It Needs a Reference Background • How do we tell if it’s a vehicle or just the street? • Determine background scene • Adapt to lighting changes * Update background regularly Background Refresh Rate
1c. Find Differences from Background - = • New Video Frame minus Background equals a Detection EventIt’s a vehicle! Or is it? • Repeat 30 times per second * Machine Vision Technology
Steps to a Valid Call • Update Background, Find Differences • Test for ValidityEliminate artifact conditions • Lighting changes • Moving vehicle shadows • Snow, Rain, Fog, etc. • It’s a Vehicle! Or is it? • User Tests • Behavior or Time tests • 3. Output Results * Patented Technologies
2. Does it meet our test?Is this what we want to detect? • Once have a “valid” vehicle call, there’s more: • Tools in the Autoscope Toolbox • YOU can further validate the detection event • By applying NEMA-TEES detector types • By applying Boolean logical tests • By testing in time or for persistence • By qualifying the detection event • Stopped vehicle • Vehicle size • Vehicle speed • Etc. * Create Information from raw detection event: Flexibility better meets your detection objectives
3. Outputs – What Do With Results? • What to do with this information: • Output demand for service to traffic controller • Actuate a relay (sign, flasher, etc.) • Send alarm to alert operator • Collect traffic data for congestion management • Display video for verification & confirmation * Video Detection as a Subsystem to overall system
How does video detection work? 3 steps – over and over and over... • Process video pictures • Test for a valid event • Output call or data or video • Repeat with consistency * Video detection technology in a nutshell
What is video detection? Summary How Does It Work? • Process video pictures • Test for a valid event • Output call or data • Repeat with consistency * Video detection technology in a nutshell
Autoscope® Basic Concepts Video Detection Examples, Occlusion…
Where do I use Video Detection? • Where to use—what applications? • Video Detection Concepts • More than just “Magic” * The Basics—Applications
Where No Detector Has Gone Before • Intersection – vehicles & bicycles • Freeway and Access Control • Temporary and Construction • Traffic Surveys (counts, speeds, …) • Tunnels and Bridges • Special Applications • Border Crossing • Runaway Truck • Red Light Enforcement & Awareness Reporting • Incident Detection and Incident Prevention • Railroad & LTR Crossings • Safety and Security (Military, HLS, etc.) • Pedestrian * Other video detection applications? More everyday
Application Groupings • Intersection – vehicles & bicycles • Freeway and Access Control • Temporary and Construction • Traffic Surveys (counts, speeds, …) • Tunnels and Bridges • Special Applications • Red Light Enforcement & Awareness Reporting • Incident Detection and Incident Prevention • Railroad Crossings • Safety and Security (Military, HLS, etc.) • Pedestrian • * Other video detection applications? More everyday
Language of Video Detection • Detection Objectives – Primary & Secondary • Field-of-View (Height & Angle) • Occlusion • Cross Lane Occlusion • Down Lane Occlusion • Cross Street Occlusion • Obstruction Occlusion • Trees and Bushes • Wires • Signal Heads • Light – glare from a building or service station lot • Light – signal heads at night!
Intersection Stop Line: Span Wire • Span wire challenges:Which is best?
Intersection Stop Line: Mast Arm • Four views of same stop line:Is there a best view?
Where to place the cameras? • Project economics typically implies or mandates use of existing infrastructure • Ideal placement however may mean new poles • Expect reasonable results with existing poles
Factors Influencing Performance 100% • Decisions made in configuration 10-15% • Decisions made during installation 25 - 30% • Decisions made by Engineer on the drafting table during design 60 – 65% 0% * The easiest changes make least difference
Mid-Block Stations • Traffic Data Collection • Queue Buildup
Freeway • Traffic Data Collection • Incident Detection & Prevention
Freeway Access Control • Traffic Data Collection • Incident Detection & Prevention
Traffic Surveys • Traffic Data Collection • Camera Position Determines Detector Placement
Data Collection • Traffic Data Collection • Driver BehaviorDetermines Detector Placement
Pedestrian Detection • Cross safely • Extend signal time • Actuate signs to warn motorists
Bike Detection • Actuate signs to warn motorists • Give bikes more time to cross
Pedestrian Detection • It works! • Difficult to combine with other detection objectives • Think straight down
Bridges • Traffic Data Collection • Automatic IncidentDetection
Tunnels • Traffic Data Collection • Automatic IncidentDetection • Smoke Detection
Special Applications: Homeland Security • Airports • Parking Structures • Train Stations • Seaports • Military Bases
Airport Red Zones • Stopped VehicleAlarms • Red Zone Monitoring
Military Airports • Taxiway Control • Aircraft of Many Sizes
Security: Gates • Over speed vehicles • Wrong-way vehicles