how-to-use-nnfw-api.md

How to Use NNFW API

Prepare nnpackage

Convert tensorflow pb file to nnpackage

Follow the compiler guide to generate nnpackge from tensorflow pb file

Convert tflite file to nnpackage

Please see model2nnpkg for converting from tflite model file.

Build app with NNFW API

Here are basic steps to build app with NNFW C API

1. Initialize nnfw_session

nnfw_session *session = nullptr;
nnfw_create_session(&session);

2. Load nnpackage

nnfw_load_model_from_file(session, nnpackage_path);

3. (Optional) Assign a specific backend

  // Use 'acl_neon' backend only
  // Note that defalut backend is 'cpu'.
  nnfw_set_available_backends(session, "acl_neon");

4. Compilation

  // Compile model
  nnfw_prepare(session);

5. Prepare Input/Output

  // Prepare input. Here we just allocate dummy input arrays.
  std::vector<float> input;
  nnfw_tensorinfo ti;
  nnfw_input_tensorinfo(session, 0, &ti); // get first input's info
  uint32_t input_elements = num_elems(&ti);
  input.resize(input_elements);
  // TODO: Please add initialization for your input.
  nnfw_set_input(session, 0, ti.dtype, input.data(), sizeof(float) * input_elements);

  // Prepare output
  std::vector<float> output;
  nnfw_output_tensorinfo(session, 0, &ti); // get first output's info
  uint32_t output_elements = num_elems(&ti);
  output.resize(output_elements);
  nnfw_set_output(session, 0, ti.dtype, output.data(), sizeof(float) * output_elements);

6. Inference

  // Do inference
  nnfw_run(session);

Run Inference with app on the target devices

reference app : minimal app

$ ./minimal path_to_nnpackage_directory