普通方式
torch_out = torch.onnx._export(model,img_tensor,"test.onnx",export_params=True)
动态batchsize方式
input_names = ['input']
output_names = ['output']
#model input_tensor 根据实际情况设置
torch.onnx.export(model, input_tensor, 'example.onnx',
export_params=True, verbose=False, input_names = input_names,
output_names=output_names, opset_version=10,dynamic_axes={"input":{0:"batch_size"},
"output":{0:"batch_size"}})