Dahua License Plate Initial Setup

Prerequisites

150×50 License Plate pixel size or higher from snapshot images
Car Traffic = 25MPH or Less

Camera Angle

Vertical Angle<30 Degree
Horizontal Angle<30 Degree
LP Angle<5 Degree
LP width : more than 130pxel, 150pixel is the best

Pixel Density

Example of Setup
Good Example: 221 Pixel Width, Check in MS Paint

Video Instructions

Video Overview-Drone Flyover

Step by Step Instructions

1. Log into the Web UI of the camera by typing the IP into a web browser.

Enter the username/password and click Login

2. Click Config (LPR) to enter the configuration menu for the LPR function

3. The LPR Config menu will be displayed

To configure the LPR function use the interface:

– Region – Set region for detection, region is within the red line.
– Detect Line – Detect line for trigger of snapshot, detect line is green.
– Shield Area – Set shield area to not identify vehicle plates, Up to 2 shield areas, Shield area is within the grey box.
– Redraw – Click to delete current config

4. Adjust the plate snapshot position to be in the yellow box.

5. Continue to make adjustments with the detection zone AND physically moving the camera until the yellow box is right on point with the expected license plate position.

Physically adjust the camera to complete proper setup.

Ensure the box matches the actual plate position and size in the video.

Step by Step Instructions – Guide

The Guide interface is useful to configure the correct settings for license plate capture

Log into the Web UI of the camera by typing the IP into a web browser.

Enter the username/password and click Login

Click the Guide tab.

On the Guide interface, you can configure capture scenarios. You can click at at the upper-right corner of Guide interface to exit at anytime.

1. Confirmation

Confirm the Software Version is the latest (Visit the Product page for latest firmware version – Link), and then click OK.

2. Plate Pixel

You can check whether the video image is properly zoomed and focused by checking the plate pixel.

Below the video frame there is an example of the optimal plate positioning:

Use the Pixel Plate settings to adjust the camera for zoom and focus

Drag the Zoom and Focus bar to adjust the image properly
Position a vehicle/plate into the camera’s view

Click Snapshot to take a snapshot of the plate (Snapshot button will become Resume)

Drag the yellow box to the position of the plate

Click Local Range to zoom the picture by 2x or 4x zoom rate (if required)

Continue to adjust the position yellow box to make it optimal plate size:

If the plate within the yellow box is larger than the optimal plate size in the example, zoom out the video image; if smaller, zoom in the video image.

It may also require reviewing proper mounting requirements/positions if any softw3are adjustments do not allow for optimal plate positioning.

Once the plate is in optimal position, click Check Pixel. Click Yes to confirm.

3. Recognition

This section will configure the recognition/identification area for detection of license plates. The sample image can be used as a reference

A sample Identification Area and Snap Line will be displayed.

To clear or Redraw these Click either Iden Area or Snap Line

Then click Redraw –

To create new Recognition settings:

Click Iden Area.

Click and draw 4 lines on the video frame to create a recognition area. Only plates in this area will be detected.

Click Snap Line.

Draw snap line by dragging mouse on the area. The snap line must cross the area. Vehicles passing this line will trigger plate detection.

3) Click Save to complete the Setup.

Click Finish, exit Guide interface and enter Live interface.

Example at Live interface:

Make sure the vehicle is within the red identification area line
The green snap line is about 1/3 of the road
Angle between the bottom of the license plate and the screen ≤5°
The license plate has more than 140 pixels.

Troubleshoot

Working Examples

Snapshot	Example of Interface	Current Configuration of Camera LPR

Snapshot Examples and Suggestions

Description	Example of Bad Capture	Current Configuration of Camera LPR	Suggested Changes
Camera is reading signs instead of license plates			Decrease Detection Range
Insufficient License Plate Pixel Density			Reposition Camera or increase Zoom
Camera reading other text from vehicle			Reposition Camera or increase zoom
Capture Angle Too Extreme			Reposition Camera to Less Extreme Angle