Documentation for Auto PSIM 1.0.1.

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The LPR channel enables license plate recognition upon request using the Camera of recognition upon request object. This object allows you to configure the camera so that it captures and sends a video image to the recognition module after a specific trigger activates. It can be, for example, a macro, a script, or some event. 

Note

For now this functionality is implemented for AR-Auto, VT, RR, AR-Railway recognition modules only.

Note

When using the Camera of recognition upon request object along with the VT recognition module, it is recommended to disable VodiCTL_VPW_DYNAMIC_ENABLE in the SDK tweaking, i.e. set the False value of this parameter, in order to prevent repeated recognition (see The VT module object settings panel).

Configure the recognition upon request as follows:

  1. Go to the Camera of recognition upon request settings panel created on the basis of the LPR channel object.

  2. From the Camera drop-down list (1), select the camera that will work upon request. 

    Note

    • The same camera can be selected in several Camera of recognition upon request objects.
    • If the camera has been selected on the settings panel of the Camera of recognition upon request object, then it will become impossible to select any camera on the settings panel of the LPR channel object (see Selecting the video cameras to work with the LPR channel).

  3. Set the Search area (2) checkbox in order to enable setting the search area border of the license plate in the frame.

    1. In the Left, Top, Right and Bottom fields, set manually or using the  button (3), by clicking which, the interactive interface of setting search area borders of the license plate appears—a video image from the corresponding video camera. You can set an arbitrary search area using the segments. To select a rectangular search area, set the Rectangular zone checkbox (5).

      Note

      The values in the Left, Top, Right and Bottom fields are specified in percentage to the surveillance window.

  4. Set the maximum and minimum size of license plates in Detection settings:

    1. Set the Max.width and Max.height parameters manually or using the  button (4), by clicking which, the interactive interface of setting the zone parameters appears—a video image from the corresponding video camera.

    2. When required, click the Stop video button, select the required area using the left mouse button and then click OK. 

      Results of setting zone parameters will automatically appear in the Max.width and Max.height fields.
      Set the Min.width and Min.height parameters the same way as Max.width and Max.height.

  5. For the Frame count (6) parameter set the number of frames that will be analyzed when recognizing the license plate.

    Note

    It is recommended to set the number of frames to no more than 1.

  6. Set the Zooming (7) checkbox in order to speed up the license plate recognition for megapixel cameras without any quality loss. The request, which will trigger the camera, can be configured in two ways:

    Note

    This checkbox is relevant only when the width oh the Search area is more than 150 pixels. The recognition speed increases: 

    • 2 times if the value of the Width parameter is more than 150 pixels;
    • 4 times if the value of the Width parameter is more than 400 pixels;
    • 8 times if the value of the Width parameter is more than 800 pixels.
  7. Set the Select with best recognition accuracy checkbox (8) to show the recognition results with the highest accuracy rate, as the bigger LP size does not always result in a better recognition accuracy.
  8. Set the Select with biggest LP checkbox (9) to show the results with the biggest LP sizes.
  9. From the Priority country drop-down list (10) select the country which LPs should be shown first.
  10. Click the Apply button (11).

The request, which will trigger the camera, can be configured in two ways:

  1. Using a macro. To do this, switch to the Programming tab in Axxon PSIM and select the Macros item in the programming tools tree. A window for creating a macro will open, enabling you to create an event of any complexity that will trigger the recognition upon request. An example of the simplest macro for recognition upon request is shown in the figure below. For details on working with macros, see Creating macros.

  2. Using a script or the IIDK interface. To do this, go to the Programming tab in Axxon PSIM and select the Scripts item in the programming tools tree. A window for creating a script will open, enabling you to create an event of any complexity that will trigger the recognition upon request. For details on working with scripts, see Creating a script. An example of a simple script for working with a camera for recognition upon request is shown below.

    QUERY_CAMERA|ID|RECOGNIZE

    where ID is ID of the camera in the Axxon PSIM objects tree. 

    For details on the IIDK interface, see Axxon PSIM Integration Developer Kit (IIDK).

License plate recognition upon request is now configured.

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