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1. Go to the settings panel of the VT module object that is created on the basis of the LPR channel object.
   

2. Set the Zooming checkbox to increase the license plate recognizing speed on mega-pixel cameras without loss of recognizing quality (1).
   This checkbox is relevant when the value of the Zone width parameter is more than 150 pixels (see Setting up Configuring the detection of the LPR channel detector). The zone is an image from the corresponding camera. The recognition speed increases:

   1. Two times if the value of the Zone width parameter is more than 150 pixels;
   2. Four times if the value of the Zone width parameter is more than 400 pixels;
   3. Eight times if the value of the Zone width parameter is more than 800 pixels.
3. To prevent the loss of processed frames, it is recommended that each megapixel of the camera 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 Number of streams for frame processing field (2):
   

   1. If the value of the Number of streams for frame processing field is 0, recognition is performed in the same stream it is started. It is the default value.

   2. If the value of the Number of streams for frame processing field is 1, recognition is performed in the parallel stream to the process that starts it. This is the recommended value.

   3. If the value of the Number of streams for frame processing field is 2 or more, recognition is performed in two or more streams simultaneously to the process that starts it. However, in this case, one license channel is used for each stream.

      Note
      title Attention!
      The specified number of streams must not exceed the number of CPU cores on the server.

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

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

6. Perform fine tuning of SDK if required (5) (see VT module object settings panel).

   Note
   title Attention!
   You must perform fine tuning of SDK only with the help of AxxonSoft technical specialists! 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_2.16.0.
   • for x64: <Auto PSIM installation directory>\Modules64\UrmLpr\VIT_2.16.0.

   You can also find out the current SDK version using the vpwfetch.exe -v command in the Windows command line, while in the corresponding folder.

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

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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).

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The start time (initialization) of the license plate recognition algorithm using a GPU can take several minutes. No license plate recognition events will be 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.