An object + license plate detection (from a video/image) solution, leveraging Open ALPR (.NET Framework) & ML.Net ONNX Detection (.NET Core).

• The startup project should be MLNetOnnxAlpr.SampleUi [Build x64]
• Change the file in MainWindow.xaml.cs -> var videoFilePath = String.Empty; [Line 77]

• This is a modified version of Microsoft’s samples "OnnxObjectDetectionWPFApp" & "OnnxObjectDetection", leveraging TinyYolo2_model.onnx.
• There were a few refactors / modifications on the overlay methods, in which it will remove overlapped overlays of identified objects.
• I looked into adding the duc.onnx model yet was unable to get the bounding boxes correct Duc.

• The source has been in a rough state for the last few years based on the issues/comments yet the last public release was close enough to the sample to piece it together.
• I attempted to rebuild with the latest source yet their build instructions were leveraged for VS15, and after creating a VM with the required dependencies / requirements the build still failed. (You might have more insight/luck.)
• I appreciate the effort/time the team put into this, yet I'm giving you a head ups if you investigate their resources further.

Open ALPR requires dependencies not included / built into OpenAlprClient, the files are included on the build:

  <ItemGroup>
    <_CopyItems Include="$(SolutionDir)\MlNetOnnxAlpr.OpenAlprClient\Dependencies\**\*.*">
      <InProject>false</InProject>
    </_CopyItems>
  </ItemGroup>
  <Target Name="PostBuild" AfterTargets="PostBuildEvent">
    <Copy SourceFiles="@(_CopyItems)" DestinationFiles="@(_CopyItems->'$(OutDir)\%(RecursiveDir)%(Filename)%(Extension)')" SkipUnchangedFiles="true" OverwriteReadOnlyFiles="true" Retries="3" RetryDelayMilliseconds="300" />
  </Target>

• Yes, it's a .NET Core application calling a .NET Framework DLL which is quite bad, yet you could create an API / micro-service to pass the bitmap too and return the relevant information, for a production end-to-end solution.

• Had the idea with a colleague, using car dash cam(s) to determine the vehicle type/information, as well as log the license plate information.
• Realized it was possible with this research publication Microsoft CNN-Automatic License Plate
• Found a few projects by MicrocontrollersAndMore OpenCV_3_License_Plate_Recognition (the source is very rough yet functional)

• Deep ANPR - Python
• Alpr-Unconstrained - Python

• Netron - Onnx Model Viewer