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Security Cameras That Capture License Plates

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License plate capture (LPC) cameras can capture clear images of license plates. This technology is typically used within license plate recognition (LPR) systems.

The cameras with license plate recognition technology use software to detect and read license plates automatically. You can use this feature for access control, parking lot management, and security systems for businesses and homes. Consider buying license plate recognition security cameras if you are worried about your residential security.

How is a license plate camera different from a regular security camera?

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Traditional surveillance cameras cannot capture clear images of number plates due to their low-light performance and noisy or grainy video output. Therefore, it is difficult to identify the characters on a license plate. It is impossible to read text when the image is blurred, and there is no way to improve the picture.

To capture license plates from moving vehicles, buying a security camera system with an adjustable shutter speed specifically designed for plate capture, also known as a license plate capture camera, is necessary.

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License plate cameras have a mode that sets a maximum gain and enhances noise filtering settings, which results in top-quality images for decoding license plate codes when using ANPR software packages.

Types of Licence Plate Cameras

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Various types of cameras are used to capture license plates, including the License Plate Capture (LPC) camera. It is specifically designed to record videos for capturing license plates. However, it doesn't usually include any advanced features.

LPR cameras are designed to take clear pictures and videos of license plates like LPC cameras. However, they come with advanced analytical tools, artificial intelligence, and ANPR/ALPR features to recognize license plates more effectively.

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License plate recognition systems (LPRs) can translate the license plate image into text data and store it in a database, which can keep track of the license plates that enter and exit your property.

License Plate Recognition (LPR) Cameras

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The LPR system includes one or more cameras that take pictures of license plates, also known as license plate capture. Then, the camera or a separate server runs license plate analytics software to process the images.

The License Plate Security Camera has a zoomed-in lens that is only suitable for capturing license plates. During the day, objects in the camera's view will appear very large, but the outcome will show excellent license plate details.

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The LPR software can detect and read license plate numbers accurately in real time.

You may save license plate numbers detected by the surveillance system in a database for later use or use them to initiate an action such as opening a gate.

Capturing License Plates

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High-resolution is crucial for achieving good image quality. This is especially important when capturing license plates, as the resolution should enable clear visibility of each letter and number. To achieve this, it is recommended to have a resolution that allows each structure to span at least two pixels.

However, resolving this at a reasonable rate is crucial, as this can cause issues with the software analysis due to a large amount of image data. Therefore, keeping the resolution below 2 MP when using LPR software directly on a camera is recommended.

What is the right height for license plate capture cameras?

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For better results, it's essential to place the security camera at the right location and height and ensure it has the appropriate lens.

You will need to do some math. Here are the variables you need to determine.


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The mounting height and capture distance determine the vertical angle between the camera and the car's direction of travel. Please ensure that the total angle does not exceed 30°.

It is better to point the camera so it faces the car front. That way, you can see the license plate more clearly.

Put the camera above the cars, not too high. But make sure you put it higher than the car headlights so it won't be too bright.

Capture Distance

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The camera captures depending on how far away it is from the road. That is called the capture distance.

The capture distance's impact on the ability to detect license plates should be considered carefully, as it can affect the process in multiple ways.

The distance from the middle of the road tells us how far away the camera needs to be from the car when it goes down the road.

Depth of Field

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The camera must be precise so the license plates look sharp and can be read. In addition, the image will look sharp in a range of distances from the camera. That range is called depth of field (DOF).

The depth of field is the area surrounding the focal plane where the image remains clear enough to be considered in focus.

The DOF can be more significant if you make the shutter in the camera smaller. However, be careful when doing this because it makes it harder for the camera to take pictures in low light.


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To ensure the license plate is parallel to the edges of the image, the camera's roll angle needs to be adjusted.

Point the camera at the road so you can see the lanes. Zoom in enough to see all the lanes you want but not any extra ones.

Lighting For License Plate Recognition Cameras

You need enough light for the system to capture a license plate. The light needs to be a particular color. Most systems use 850nm Infra-Red (IR) light.

IR is the best way to take a picture of a car's license plate. It makes a faint red light, but you can't see it. Most systems only use IR and not any other kind of light so that it won't distract the driver.

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Sometimes it is hard to read license plates because they are dirty or the sun or bright lights are shining. This technology helps us get a clear picture of the plate even with these problems.

Sometimes, you need to know what color a plate is. To do this, you can use white light. But since white light is very bright and can be seen by people easily, it might not work in some situations.

Constant Light And Pulsated Light

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When setting up an ANPR/LPR system, you must decide if you want constant or pulsed light.

Constant light means the light is always switched on and stays on all the time.

Pulsated light is when a light flashes very quickly. It works with the camera's shutter to take pictures of things that move fast. This kind of lighting helps get the best shot possible.

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Pulsed lighting helps capture cars that are moving quickly. If the vehicle is going fast, the dedicated camera must take pictures faster, and more light is required. The faster shutter lets less light reach the camera sensor.

Night Vision

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Capture license plates during nighttime are required to have artificial lighting. For this purpose, infrared (IR) light is generally used due to its invisibility to the human eye, and it does not cause any issues like driver blindness.

The camera can either have LEDs with infrared light or use external sources to enhance visibility.

License plates are often designed to reflect infrared light, which makes them easier to see in dark or cloudy conditions.

Adjusting the License Plate Camera Settings

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How the camera is set up will determine how well it can take pictures of license plates.

A license plate recognition camera comes with its settings and does not need to be changed.

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However, other cameras might require you to change these settings:

  • If the camera's shutter time is too long, moving vehicles in the image will create motion blur. You should consider the maximum shutter time to avoid this.
  • The camera has a setting called contrast. It can make the image's background darker at night and make the white of the license plate look brighter. Be careful - if this setting is too high, it could ruin how it seems.
  • Tone mapping is a way to make the dark parts of a picture more visible. But if it is not used correctly, it can make bright spots too bright and add extra noise. When you use a security camera to record license plates, it is better to use less tone mapping.
  • The wide dynamic range helps ensure that details in dark areas can be seen and also stops the camera from getting too bright when there is a lot of light.

Automatic Number Plate Recognition (ANPR) Software

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ANPR cameras use OCR (Optical Character Recognition) software to capture license plate numbers and store pictures of the plates. This requires using specific analytics software to extract license plate numbers from a video stream. 

As AI and neural networks advance, cameras become more capable of image analytics. By improving algorithms and processors, the time needed to analyze each image will decrease, and distributed systems will become more competitive.

Where does the license plate camera software run?

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You can install the LPR software on a camera itself or remote servers. The system can identify and read license plates on vehicles, whether they are stationary or in motion, and can capture both numbers and letters accurately.

LPR software on a remote server

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Using a remote server can give you more power. However, it will need more internet to send the videos somewhere else.

If you have many cameras, making the video streams work well might be problematic because they could slow down the network.

LPR software on the camera

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This camera has special software that only sends the letters and numbers of the license plate to a central server. It also usually dispatches a picture of the license plate and what was around it.

The camera has special software that helps it work better. This makes it so the network can stay relaxed. It is easy to make the system bigger by adding more cameras without anything else.

Storing and Reviewing License Plate Captures

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Automated license plate recognition (ALPR) is a system that uses cameras, computers, and databases. It can quickly take pictures of license plates and match the numbers to a list in the database.

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ALPR systems can gather additional data, such as the whereabouts of cars on specific dates and times. As a result, these systems can monitor and profile individuals by tracking their locations over an extended period, potentially aiding authorities in conducting surveillance.

The ALPR system compares the license plate recognition file with pre-existing data files. If a match is found, the user will receive an audible alert and a notation on their computer screen.

The ALPR system checks all vehicles equally, making it a fair and unbiased public safety tool. The information gathered by ALPR cameras can also be helpful for criminal investigations.

Video Surveillance Systems And Privacy

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ALPR systems can cause problems for people's privacy. People might not follow laws about privacy, and this system might take away people's rights and freedom.

To protect privacy, it is crucial to have good rules, plans, and technology in place. This is especially important because most drivers are just living their everyday lives.

Tips For Placing an LPR Camera

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Here are some suggestions for placing special capturing plates cameras in the correct locations:

  • To ensure that the camera captures license plates effectively, it should be positioned at a distance suitable for the speed of the cars.
  • It is recommended to position the camera so that the angle between it and the car's travel direction is minimized. This will allow for a head-on view of the license plates, and a total angle of less than 30° is suggested.
  • If the vehicles are moving quickly, You must place the camera further to allow enough time for the system to read the plate before the car is out of sight.
  • For better results, keep the ambient lighting near the camera while capturing license plates as they reflect light in the same direction.
  • Use unique lights called infrared lights that you can't see at night. They will only bother drivers if their vehicle passes.
  • It is essential to consider the camera's depth of field and the range of its infrared capabilities, as they may affect the results.
  • It is advised to set a maximum shutter time to avoid motion blur. The ideal shutter time will vary based on the camera's alignment and the vehicle's speed.
  • To prevent overexposure of the license plate, set a maximum limit to the camera's gain.


Why are overview cameras recommended with LPR cameras?

A license plate is a surveillance camera specifically designed to recognize, capture, and record the license plates of vehicles. The recorded video captured by these cameras includes license plates.

Which camera is superior for LPR?

Here are some recommendations for buying the right camera that can capture license plate numbers:
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The Axis LPR camera is an IP camera that delivers high-quality video footage at HDTV 1080p through an 18~137mm lens. It has a sturdy exterior, supports onboard storage using an SD card (not included), and can be operated using third-party software. Additionally, this license plate reader camera has a magnification of up to eight times and is weather-resistant.This camera has some limitations: a maximum capture speed of around 81 miles per hour, a capture range of 131 feet, and an optimized range of 164 feet. However, although the camera may be expensive, it is highly sophisticated and can be helpful for commercial security.

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Geovision offers license plate reader cameras at various price points. For example, one of the models they offer has a maximum FPS of 30 at 1920x1080 resolution, a 9-22mm motorized lens, dual streams in MJPEG or M.264 format, a built-in heater with a fan for cold environments, two-way audio, PoE, and a weatherproof exterior.

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The LPR camera from Oculur, offered by A1 Security Cameras, is affordable and delivers excellent results. It uses Darkfighter technology, has an IP67 weatherproof rating, is IK10 rated for vandal resistance, offers face detection, four behavior analysis options, and works with 3rd party software. The camera also has a 2.8~12mm motorized lens.

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LTS Security has a range of license plate reader cameras available in different price ranges. The cheaper options come with a motorized 6~22mm lens and are weatherproof with night vision. They also support low bit rates and produce an image of 1920×1080 at 30fps.

On the other hand, the LTS LPR camera is more costly, but it can produce high-quality images with a resolution of 1920X1080 at 60fps using an 8~32mm varifocal lens. Additionally, it comes with a more robust weatherproof exterior. You can add functions like behavior analysis, facial recognition, database support for license plates, alarms, and more.

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