License Plate Capture Testedby John Honovich, IPVM posted on May 21, 2011 About John Contact John
Capturing license plates is one of the best ways to identify suspects and intruders. As such, it is highly desirable that outdoor surveillance cameras are able to do so.
However, capturing license plates is challenging. While license plates are relatively small, surveillance cameras are generally expected to cover a large area. Even worse, at night time, headlights make capturing license plates quite hard.
In the last few years, hopes have risen as megapixel cameras have become mainstream. Theoretically, the much greater resolution should allow for simultaneous wider coverage areas and capturing of license plates.
In this report, we share our results from a real world license plate capture (LPC) test. We choose a two lane vehicle entrance to a public parking facility with a kit of 5 IP cameras (including SD, 720p, 3MP and 5MP cameras from Axis, Arecont Vision, Bosch, Sony and StarDot) to better understand the tradeoffs ourselves. As the image below shows, we captured a moderately wide Field of View focused on the two lane entrance:
We placed our camera kit in line with the vehicle entrance to capture vehicles entering and exiting the lot. The overhead image and map below demonstrates the coverage, distances and pixels per foot at different positions.
Then we analyzed a series of scenes to see how performance varied across the cameras. We digitally zoomed each camera to the same level to see the differences. Below is an example of our analysis:
Inside the Pro section, we provide analysis on 14 scenes, revealing the performance of each camera in each scene. The 14 scenarios we choose were:
- Daytime LPC (Far)
- Daytime LPC (Mid)
- Daytime LPC (Near)
- Day vs Night LPC
- Ground Level vs High Mounting LPC
- 11ft vs 7ft Mounting LPC
- Low Beams vs High Beams LPC
- Headlamps Off vs Low Beams LPC
- Nighttime Van LPC (Ambient Lighting)
- Nighttime Van LPC (White Light LED)
- Nighttime Van LPC (IR LED)
- Nighttime Sedan LPC (Ambient Lighting)
- Nighttime Sedan LPC (White Light LED)
- Nighttime Sedan LPC (IR LED)
Many factors impact performance, making LPC one of the most challenging achievements in surveillance, especially when the camera is being used for both license plate capture and general surveillance. Inside, we show and explain each of the key factors involved.
Most Recent Industry Reports
7 Quizzes - Test Your Co-Workers on Apr 14, 2014
A major new offering, now IPVM members can take a series of 7 quizzes, plus they can assign them to their co-workers who are also IPVM members. Make sure you truly are on top of surveillance ...
Super Low Lux Minidome Tested on Apr 10, 2014
'Super' low light cameras have become increasingly common in box and full size cameras. However, no one we know has offered them in a minidome, the most common form factor for many users, valu...
Testing 'Megapixel' Analog Camera on Mar 26, 2014
Megapixel analog sounds like a contradiction in terms. 'Analog' by definition, or at least in common use, is constrained by 60+ year old NTSC / PAL specifications and cannot be 'megapixel.' Howeve...
Ranking 95 Surveillance Manufacturers Interest on Mar 24, 2014
IPVM has ranked interest levels in 95 surveillance manufacturers from most to least. These are the companies covered: Over 400 IPVM members selected which of these companies they were interested...
2014 Surveillance Test Results Guide Released on Mar 19, 2014
Inside, get the 50 page IPVM 2014 Surveillance Test Results Guide and register for the 1 hour live webinar. In the past year, IPVM has spent thousands of hours conducting over 75 tests, representi...
Testing Pelco SureVision 2.0 on Mar 17, 2014
Pelco's new SureVision 2.0 line promises superior low light and wide dynamic range capabilities, claiming "industry-leading image quality in the most difficult lighting conditions." But does it del...
IPVM Site Improvements Directory on Mar 15, 2014
IPVM continuously develops new features and improvements. This document will serve as a directory of those, like 'release notes' but with more color and commentary. 2014 Site Improvements Added N...
Shootout: Megapixel vs Analog Cameras on Mar 12, 2014
How much does resolution really make a difference? For those purchasing budget or entry level systems, what, if any gain, does one get for higher resolution? In this test report, we did head to he...
Announcing News Monitoring Service on Mar 11, 2014
Now get weekly alerts on 110+ security companies, including new information from their websites as well as articles and discussions on them. This is the most powerful way to stay informed on the co...