Change dynamic shape in fixed shape using C++

[LaurentBerger]

I want to change dynamic shape in a fixed shape in C++

Question

How to do it in C++?

Further information

First i try to change input size :

        std::map<std::string, int> valSubstitute;
        val["w"] = 640;
        val["h"] = 480;


            for (int i = 0; i < graph_proto->input_size(); i++)
            {
                auto node = graph_proto->input(i);
                for (int j = 0; j < node.type().tensor_type().shape().dim_size(); j++)
                {
                    auto dimx = node.type().tensor_type().shape().dim()[j];
                    if (dimx.has_dim_param())
                    {
                        if (valSubstitute.find(dimx.dim_param()) != valSubstitute.end())
                        {
                            std::string key(dimx.dim_param());
                            dimx.clear_dim_param();
                            dimx.set_dim_value(valSubstitute[key]);
                        }
                    }
                    else
                        std::cout << "dim " << dimx.dim_value() << "\n";
                }
            }

then I scan my change

            std::cout << "Scan 2 : graph_proto->input_size \n";
            for (int i = 0; i < graph_proto->input_size(); i++)
            {
                auto node = graph_proto->input(i);
                for (int j = 0; j < node.type().tensor_type().shape().dim_size(); j++)
                {
                    auto dimx = node.type().tensor_type().shape().dim()[j];
                    if (dimx.has_dim_param())
                    {
                        std::cout << "dim " << dimx.dim_param() << "\n";
                        if (valSubstitute.find(dimx.dim_param()) != valSubstitute.end())
                            dimx.set_dim_value(valSubstitute[dimx.dim_param()]);
                        if (dimx.has_dim_param())
                            std::cout << "No !dim " << dimx.dim_param() << "\n";
                    }
                    else
                        std::cout << "dim " << dimx.dim_value() << "\n";
                }
            }

result is : no change in scan 2

Scan 1 : graph_proto->input_size
dim 1
dim 3
dim 480
dim 640
Scan 2 : graph_proto->input_size
dim 1
dim 3
dim h
dim w

• Is this issue related to a specific model?
  No but i work on dexined model

Notes

I'm not an expert in Onnx

[LaurentBerger]

solved : clone ModelProto and change data