ONNX To Pytorch Conversion

[SuperSecureHuman]

Addresses onnx to torch conversion from - #133

[SuperSecureHuman]

I have no idea where this error is being originated. Any help would be appreciated

Manually invoking the conversion works, I am not sure where the input is expected to be str/path.

The convert function can take in ModelProto, but the tests is giving it ModelParams (I think)

Edit: This is fixed now

[valeriosofi]

Hi @SuperSecureHuman, I tried in my local machine an optimization with the onnx->torch conversion and I found two issues:

• in convert_onnx_to_torch() you save the model to disk and return the path to the model, but nebullvm expects the model to be a torch.nn.Module in the later steps, so I would modify the function like this:

    try:
        torch_model = torch.fx.symbolic_trace(convert(onnx_model))
        return torch_model
    except Exception as e:
        logger.warning("Exception raised during conversion of ONNX to Pytorch."
                        "ONNX to Torch pipeline will be skipped")
        logger.warning(e)
        return None

I had to add also torch.fx.symbolic_trace because otherwise the conversion to torchscript didn't work in the pytorch pipeline.

• The PytorchBackendInferenceLearner expects input tensors to be PyTorch tensors, but in this case they will be Numpy arrays. We should implement a NumpyPytorchBackendInferenceLearner class that converts the np arrays to torch tensors before calling the PytorchBackendInferenceLearner run method and then converts the result back to a np array. We do the same thing in the other inference learners (you can check for example theONNXInferenceLearner, you will see that there are three additional classes implemented: PytorchONNXInferenceLearner, TensorflowONNXInferenceLearner, NumpyONNXInferenceLearner)

Can you please solve these two points? I would do it myself but now I'm working on stable diffusion and I have not much time. Thanks ;)