[lights0123]

They're using ONNX Runtime to run the model, which has a C API: https://onnxruntime.ai/docs/get-started/with-c.html. You could also use any other ML inference library that supports the ONNX format.

You'd need to look at this project's code to see how it converts input data to the expected matrix format, though.

[mattismegevand]

Exactly, the transformation done for inference are located here: https://github.com/mattismegevand/invertornot/blob/main/api/...