Optimizing the operation of the License plate recognition VT on GPU in Linux OS

Starting with DetectorPack 3.10, a utility was added to the VT LPR add-on (see Installing DetectorPack add-ons), which allows you to create GPU neural network caches without using Axxon One. The presence of the cache speeds up the initialization and optimizes video memory consumption.

To optimize the operation of the License plate recognition VT on GPU, do the following:

1. Stop the server (see Stopping the server).
   

   Attention!

   If the system has the software running on GPU, it is necessary to stop its operation. 

2. Login as ngp superuser:

   1. In the command prompt, run the command:

      sudo su ngp

   2. Enter the password for the root superuser.

3. Create a folder with a custom name to store the cache. For example:

   mkdir /opt/AxxonSoft/AxxonOne/gpucache

4. Change folder permissions:

   chmod -R 777 /opt/AxxonSoft/AxxonOne/gpucache

5. Create the GPU_CACHE_DIR system variable:

   1. Go to the /opt/AxxonSoft/AxxonOne/ folder:

      cd /opt/AxxonSoft/AxxonOne

   2. Open the instance.conf file for editing:

      nano instance.conf

   3. Add the following line to the file:

      export GPU_CACHE_DIR="/opt/AxxonSoft/AxxonOne/gpucache"

      Attention!

      If you change the server configuration (see Changing the configuration of the Axxon One Server in Linux OS) or update to a new version of Axxon One, the system variables previously added to the instance.conf file will be deleted (see Creating system variables in Linux OS).

   4. Save the file using the Ctrl+O keyboard shortcut.

   5. Exit file editing mode using the Ctrl+X keyboard shortcut.

   6. Run the following command in the terminal:

      export GPU_CACHE_DIR="/opt/AxxonSoft/AxxonOne/gpucache"

6. Go to the /opt/AxxonSoft/DetectorPack/ folder:

   cd /opt/AxxonSoft/DetectorPack

7. Run the following command:

   ./VTGpuCacheGenerator

8. Enter the required countries in alphabetic form.
   
   Expand the list of countries

   ad (Andorra)
   al (Albania)
   am (Armenia)
   ar (Argentina)
   at (Austria)
   au (Australia)
   az (Azerbaijan)
   ba (Bosnia and Herzegovina)
   be (Belgium)
   bg Bulgaria
   bh (Bahrain)
   bn (Brunei)
   bo (Bolivia)
   br (Brazil)
   bw (Botswana)
   by (Belarus)
   ca (Canada)
   ch (Switzerland)
   cl (Chile)
   co (Colombia)
   cz (Czech Republic)
   de (Germany)
   dk (Denmark)
   dz (Algeria)
   ec (Ecuador)
   ee (Estonia)
   es (Spain)
   fi (Finland)
   fr (France)
   gb (Great Britain)
   ge (Georgia)
   gr (Greece)
   gt (Guatemala)
   hk (Hong Kong)
   hn (Honduras)
   hr (Croatia)
   hu (Hungary)
   id (Indonesia)
   il (Israel)
   in (India)
   ir (Iran)
   it (Italy)
   jo (Jordan)
   ke (Kenya)
   kg (Kyrgyzstan)
   kr (Republic of Korea)
   kz (Kazakhstan)
   li (Liechtenstein)
   lk (Sri Lanka)
   lt (Lithuania)
   lu (Luxembourg)
   lv (Latvia)
   mc (Monaco)
   md (Moldavia)
   me (Montenegro)
   mn (Mongolia)
   mt (Malta)
   mx (Mexico)
   my (Malaysia)
   ng (Nigeria)
   ni (Nicaragua)
   nl (Netherlands)
   no (Norway)
   nz (New Zealand)
   pa (Panama)
   pe (Peru)
   ph (Philippines)
   pl (Poland)
   pt (Portugal)
   py (Paraguay)
   ro (Romania)
   rs (Serbia)
   ru (Russia)
   se (Sweden)
   sg (Singapore)
   si (Slovenia)
   sk (Slovakia)
   su (USSR)
   sv (El Salvador)
   tj (Tajikistan)
   tm (Turkmenistan)
   tn (Tunisia)
   tr (Turkey)
   tw (Taiwan)
   ua (Ukraine)
   us (USA)
   uy (Uruguay)
   uz (Uzbekistan)
   vn (Vietnam)
   za (Republic of South Africa)
   zm (Jamaica)

9. After you select all required countries, enter done.
10. The default resolution is 1920x1080 pixels. If you want to change the resolution, enter y and the required resolution. For example, 2048.
11. To leave the default value, enter n.
    
12. Specify the minimum width of the license plate according to the actual size of the license plate in the frame as a percentage. The minimum allowed value is 0, the maximum value is 100.
    
13. Specify the ID of the required GPU (see Selecting Nvidia GPU when configuring detectors).
14. Press Enter.

As a result, the process of creating cache starts, which takes about 30 minutes. The duration of the process depends on the selected types of cache, number of countries, and Nvidia GPU model.

Optimizing the operation of the License plate recognition VT on GPU is complete.