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Configuring the VT software module

Configure the VT Configure the VIT program module as follows:

1. Go to the
VIT module object settings panel, which is
2. settings panel of the VT module object that is created on the basis of
the LPR Channel object
3. the LPR channel object.
   Image Modified

4. Set the Zooming checkbox

checked

5. to increase the license plate recognizing speed on mega-pixel

video

6. cameras without loss of recognizing quality (1).
   

Info

title	Note

This check box

7. This checkbox is relevant when the value of the Zone width parameter is more than 150 pixels (see Setting up the detection of the LPR channel

detector section

8. ). The

recognizing speed is increasing:

9. zone is an image from the corresponding camera. The recognition speed increases:

   1. Two
2
10. 1. times if the value of the Zone width parameter is more than 150 pixels;
4
11. 1. Four times if the value of the Zone width parameter is more than 400 pixels;
8
12. 1. Eight times if the value of the Zone width parameter is more than 800 pixels.
13. To prevent the loss of processed frames, it is recommended that each megapixel of the
video
14. camera
be
15. is processed in a separate stream. If there is a loss of frames, then it is necessary to increase the number of streams in
the 
16. the Number of streams for frame processing field (2):
    

    1. If the value of the Number of streams for frame processing field is 0, recognition

will be

17. 1. is performed in the same stream it

was

18. 1. is started. It is the default value.

    2. If the value of the Number of streams for frame processing field is 1, recognition

will be

19. 1. is performed in the parallel stream to the process that starts it. This is the recommended value.

    2. If the value of the Number of streams for frame processing field is 2 or more, recognition

will be

20. 1. is performed in two or more streams simultaneously to the process that starts it. However, in this case,

1

21. 1. one license channel is used for each stream.

       Note
       title Attention!
       The specified number of streams

should

22. 1. must not exceed the number

of CPU

23. 1. of CPU cores on the

Server

24. 1. server.

25. From the License type drop-down list (3), select the type of license used:
    default - the
    • • default—the license type is determined automatically;
    fast (25 fps)
    • • fast—25 FPS;
    slow (6 fps)

    • • slow—6 FPS.

        Note
        title Attention!
        If you select the license type that is not in the key, then license plate recognition will not work.

    • Set the Generate unrecognized LP event checkbox (4), if it is necessary to generate a NOT DETECTED event for
    vehicles whose LP was't
    • vehicles which license plate number could not be recognized.

    • Perform fine tuning of SDK if required (5) (see

    VIT

    • VT module object settings panel).

      Note
      title Attention!

    Fine

    • You must perform fine tuning of SDK

    is to be performed

    • only with the help of AxxonSoft technical specialists!

    Info

    title	Note

    The current SDK version can be found

    • When fine tuning the SDK parameters VodiCTL_VPW_DYNAMIC_WITH_DUPLICATE, VodiCTL_VPW_DYNAMIC_OUTPUT_TIMEOUT and VodiCTL_VPW_DYNAMIC_OUTPUT_FRAMECOUNT, the values of the corresponding fields of the LPR channel also change (for details, see Setting up the display of LP recognition results).

      You can find out the current SDK version by the name of the VIT_<SDK version> folder, for example:

      • for x32: <Auto PSIM installation directory>\Modules\UrmLpr\VIT_2.
    14
    • • 16.0.
      • for x64: <Auto PSIM installation directory>\Modules64\UrmLpr\VIT_2.
    14
    • • 16.0.
    Also,

    • You can also find out the current SDK version

    can be found

    • using the vpwfetch.exe -v command in the Windows command line, while in the corresponding folder.

    • Click Apply button (6) to save the changes.

The VIT program module VT software module is now configured.

...

Tracking the disappearance of a recognized license plate

It is possible to track the disappearance of the recognized

...

license plate. If the recognized

...

license plate disappeared from the camera field of view and was not recognized again within the specified time,

...

the lost

...

license plate event will be generated. To enable this feature, in the VIT.TimeoutLostNumber parameter, set the time in

...

milliseconds after which the lost number event will be generated (for details, see Registry keys reference guide, for more information about working with the registry, see Working with Windows OS registry).

To ensure the operation of this feature, it is necessary to set the

...

true value for the VodiCTL_VPW_DYNAMIC_ENABLE

...

 parameter (see The

...

VT module object settings panel).

...

License plate recognition when there are problems with templates or templates are absent

It is possible to interpret recognized characters as text if, for example, there are problems with template recognition or if the recognized license plates don't match known templates.

...

To ensure the

...

operation of

...

this feature, it is necessary to

...

set the true value for the VodiCTL_VPW_TREAT_SYMBOLS_AS_TEXT parameter (see The VT module object settings panel).

Using a GPU for VT license plate recognition

By default, only the CPU resources are used. To enable the usage of the GPU computing resources, do the following:

1. Download the TensorRTCudaCudnn_SDK_Installer.zip distribution kit from Hotfixes of Axxon PSIM and vertical solutions.
2. Unpack the downloaded archive.
3. Install this software on the computer that has Auto PSIM installed.
4. On the settings panel of the LPR channel object, select a GPU for license plate recognition (see Selecting a device for license plate recognition).

The start time (initialization) of the license plate recognition algorithm using a GPU can take several minutes. No license plate recognition events are received until initialization is complete.

If recognition doesn't start, delete the cache files from the VT_Cache folder located at C:Windows and restart Axxon PSIM. After that, wait for the caching process to complete. As a result, cache files appear in the VT_Cache folder, and GPU is used for recognition.

...