Page History

ANPR is a detection tool that reads license / number  plates of vehicles in FoV.

...

To configure ANPR, do as follows:

1. Download ANPR (VT) from the website and install it. 
2. Create the Select the License plate recognition (VT) object (1) and select it.
   

3. If you require using need to use this detection tool for real-time number license plate recognition, set the corresponding parameter to Yes (2)(see Configuring real-time vehicle license plate recognition), set the corresponding parameter to Yes (2).

4. If you need to enable recording of metadata to the database, select select Yes from the Record Objects objects tracking list (3).
5. If a the camera supports multistreaming, select the stream for which detection is needed. Selecting a low-quality video stream allows reducing the load on the Server (4).

6. If necessary, enable advanced image analysis (1).

   Yes – improves the quality of recognition under adverse conditions (for example, if the characteristics / settings of the camera do not fully meet the requirements, or in bad weather).  The processing time of the frame increases by 20-30%, depending on its size.  Under normal conditions, this setting does not affect the quality of recognition
   Image Removed

7. To recognize the numbers at sharp angles with respect to the camera, select Yes in the Algorithm of recognition of distorted LP image field (2).

8. Set the image contrast threshold (3). The default value is 40 . On a high-quality image, increase this value to 50-60. If the image has poor contrast, lower this value. 

9. Select detection tool working mode: standard or neural (1). 

   Image Added

10. In the appropriate fields, select one or more countries for ANPR (

    4

    2).

    Note
    title ImportantAttention!
    The more countries you select, the slower the recognition works and the greater the likelihood of the recognition error.

    
    

    Info
    title Note
    To recognize the old USSR license plates, you need to select the corresponding country in the list.

    
    

11. Select a processing resource for decoding video streams (3) (see Hardware requirements for GPU based video decoding). When you select a GPU, a stand-alone graphics card takes priority (when decoding with NVIDIA NVDEC chips). If there is no appropriate GPU, the decoding will use the Intel Quick Sync Video technology. Otherwise, CPU resources will be used for decoding.

12. Analyzed framed are scaled down to a specified resolution (14, 1920 pixels on the longer side). This is how it works:

    1. If the longer side of the source image exceeds the value specified in the Frame size change field, it is divided by two.

    2. If the resulting resolution falls below the specified value, it is used further.

    3. If the resulting resolution still exceeds the specified limit, it is divided by two, etc.

       Info
       title Note
       For example, the source image resolution is 2048*1536, and the limit specified value is set to 1000. In this case, the source resolution will be divided  halved two times (down to 512*384) : , as after the first division, the number of pixels on the longer side exceeds the limit (1024 > 1000).

    Image Removed

    1. 
       

       Info
       title Note
       If detection is performed on a higher resolution stream and detection errors occur, it is recommended to reduce the compression.

       
       

    
    

13. Select the current license type (25).

    License	Description
    Search in archive	Basic ANPR Search License. Attention! This type of license provides a 30-sec delay between the number recognition and the corresponding event

    . 

    (see Vehicle number plate recognition and search).
    Standard (25 FPS or 6 FPS)	The 25 FPS license has a priority. The 6 FPS license is used only if you don't have

    no

    25 FPS license. You cannot use the

    number

    license plate recognition function if you have

    no FPS

    not purchased both licenses

    purchased

    .
    Fast speed (25 FPS)	The "Fast" license allows you to process video feeds up to 25

    fps

    FPS with a maximum vehicle speed of 150 km/h. You

    have to obtain an appropriate license to make ANPR work.

    cannot use the license plate recognition function if you have not purchased the license.

    Slow speed (6 FPS)

    6 FPS

    The "Slow" license allows you to process video feeds up to 6

    fps

    FPS with a maximum vehicle speed of 20 km/h. You

    have to obtain an appropriate license to make ANPR work

    cannot use the license plate recognition function if you have not purchased the license.

    
    

    Note
    title ImportantAttention!
    All license types except the standard one (Search in archive) require the hardware key or the software key activation (see Activating a software license key for the ANPR Licensing of the software module for License plate recognition (VT)). You can use a 60-day trial key (see Activating the trial version Licensing of the ANPR via a software keysoftware module for License plate recognition (VT)).

    
    

    Note
    title Important Attention!
    You can On a virtual machine, you may use only a hardware key on virtual machines. To use a hardware key, select the Standard (25 FPS or 6 FPS) license type.

    
    

14. To set up a number plate recognition event:

15. Specify the minimum percentage of similarity between the recognition result and the corresponding number plate template, for positive LPR result (7). Use this parameter to filter the results by reliability.

By default, a number plate recognition event is registered after a track containing a number plate disappears from FOV. You can set the moment of registration to a Timeout in seconds (9), or to reaching a similarity percentage specified in the LP display quality field (3). If both parameters are set to non-zero, the recognition event will be registered upon matching the first condition.

Info
title Note
The LP display quality parameter value must be no lower than the Minimum similarity value.

Set the maximum and minimum width of the vehicle number license plate as a percentage of the FoV width FOV width (46, 6 7).

Note
title ImportantAttention!
The Minimum LP width parameter affects the CPU load as follows: the higher the parameter is, the higher the load.

Specify the maximum number of recognition threads (5). If the value is 0, the recognition process will occur in the same thread that starts it.

Note
title Important
The cumulative value of this parameters across all LPR detection tools must not exceed the number of CPU cores and is limited to 100.




16. Choose a processor to run detection on (8, see Hardware requirements for License plate recognition (VT), General Information on Configuring Detection). In standard mode, detection runs on the CPU only. In neural network analysis mode, the algorithm runs on the NVIDIA GPU.

17. Set the number of frames required for LPR/ANPR (89). This is though a necessary condition, but it is not sufficient for the first output. This condition delays the LPR output.   This parameter allows to increase increasing the reliability of the results, as well as to hide hiding false positives.

18. In the Tracker Timeout field, set a time interval in seconds after which the tracking of a vehicle is reset (10).

    Info

    title	Note

    Use this setting to eliminate double-triggering in such cases as, for example, another recognition of the same number after it has been obstructed for some time, and then reappears in scene.

    If you set Tracker Timeout to a value greater than a probable time of obstruction, the detection tool will not double-trigger

    If necessary, configure the advanced detection settings (see Fine-tuning the VT number plate detection tool).

19. You can configure an the ANPR zone area in FoVFOV. The zone area is resized by moving the anchor points.
    Image RemovedImage Added

    Info
    title Note
    For your convenience, you can click the Image Removed button the Image Added button and configure the mask on a still frame / snapshot. To undo, click this button again.

    
    

    Info
    title Note
    Detection zone area is displayed by default. You can click the Image Removed button the Image Added button to hide the zonearea. To undo, click this button again.

    
    

20. Click the Apply button.

Configuration of ANPR  ANPR is now complete.