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openvino/docs/OV_Runtime_UG/integrate_with_your_application.md
2022-12-20 23:05:11 +01:00

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Integrate OpenVINO™ with Your Application

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.. toctree:: :maxdepth: 1 :hidden:

openvino_docs_OV_UG_Model_Representation openvino_docs_OV_UG_Infer_request openvino_docs_OV_UG_Python_API_exclusives openvino_docs_MO_DG_TensorFlow_Frontend

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Following these steps, you can implement a typical OpenVINO™ Runtime inference pipeline in your application. Before proceeding, make sure you have installed OpenVINO Runtime and set environment variables (run <INSTALL_DIR>/setupvars.sh for Linux or setupvars.bat for Windows, otherwise, the OpenVINO_DIR variable won't be configured properly to pass find_package calls).

ie_api_use_cpp

Step 1. Create OpenVINO™ Runtime Core

Include next files to work with OpenVINO™ Runtime:

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@snippet docs/snippets/src/main.cpp include

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@sphinxtab{Python}

@snippet docs/snippets/src/main.py import

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@sphinxtab{C}

@snippet docs/snippets/src/main.c include

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Use the following code to create OpenVINO™ Core to manage available devices and read model objects:

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@sphinxtab{C++}

@snippet docs/snippets/src/main.cpp part1

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@sphinxtab{Python}

@snippet docs/snippets/src/main.py part1

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@sphinxtab{C}

@snippet docs/snippets/src/main.c part1

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Step 2. Compile the Model

ov::CompiledModel class represents a device specific compiled model. ov::CompiledModel allows you to get information inputs or output ports by a tensor name or index. This approach is aligned with the majority of frameworks.

Compile the model for a specific device using ov::Core::compile_model():

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@sphinxtab{C++}

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@sphinxtab{IR}

@snippet docs/snippets/src/main.cpp part2_1

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@sphinxtab{ONNX}

@snippet docs/snippets/src/main.cpp part2_2

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@sphinxtab{PaddlePaddle}

@snippet docs/snippets/src/main.cpp part2_3

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@sphinxtab{ov::Model}

@snippet docs/snippets/src/main.cpp part2_4

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@endsphinxtabset

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@sphinxtab{Python}

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@sphinxtab{IR}

@snippet docs/snippets/src/main.py part2_1

@endsphinxtab

@sphinxtab{ONNX}

@snippet docs/snippets/src/main.py part2_2

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@sphinxtab{PaddlePaddle}

@snippet docs/snippets/src/main.py part2_3

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@sphinxtab{ov::Model}

@snippet docs/snippets/src/main.py part2_4

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@endsphinxtabset

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@sphinxtab{C}

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@sphinxtab{IR}

@snippet docs/snippets/src/main.c part2_1

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@sphinxtab{ONNX}

@snippet docs/snippets/src/main.c part2_2

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@sphinxtab{PaddlePaddle}

@snippet docs/snippets/src/main.c part2_3

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@sphinxtab{ov::Model}

@snippet docs/snippets/src/main.c part2_4

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@endsphinxtabset

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The ov::Model object represents any models inside the OpenVINO™ Runtime. For more details please read article about OpenVINO™ Model representation.

The code above creates a compiled model associated with a single hardware device from the model object. It is possible to create as many compiled models as needed and use them simultaneously (up to the limitation of the hardware resources). To learn how to change the device configuration, read the Query device properties article.

Step 3. Create an Inference Request

ov::InferRequest class provides methods for model inference in OpenVINO™ Runtime. Create an infer request using the following code (see InferRequest detailed documentation for more details):

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@snippet docs/snippets/src/main.cpp part3

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@sphinxtab{Python}

@snippet docs/snippets/src/main.py part3

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@sphinxtab{C}

@snippet docs/snippets/src/main.c part3

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Step 4. Set Inputs

You can use external memory to create ov::Tensor and use the ov::InferRequest::set_input_tensor method to put this tensor on the device:

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@snippet docs/snippets/src/main.cpp part4

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@sphinxtab{Python}

@snippet docs/snippets/src/main.py part4

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@sphinxtab{C}

@snippet docs/snippets/src/main.c part4

@endsphinxtab

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Step 5. Start Inference

OpenVINO™ Runtime supports inference in either synchronous or asynchronous mode. Using the Async API can improve application's overall frame-rate: instead of waiting for inference to complete, the app can keep working on the host while the accelerator is busy. You can use ov::InferRequest::start_async to start model inference in the asynchronous mode and call ov::InferRequest::wait to wait for the inference results:

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@sphinxtab{C++}

@snippet docs/snippets/src/main.cpp part5

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@snippet docs/snippets/src/main.py part5

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@snippet docs/snippets/src/main.c part5

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This section demonstrates a simple pipeline. To get more information about other ways to perform inference, read the dedicated "Run inference" section.

Step 6. Process the Inference Results

Go over the output tensors and process the inference results.

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@snippet docs/snippets/src/main.cpp part6

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@snippet docs/snippets/src/main.py part6

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@snippet docs/snippets/src/main.c part6

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Step 7. Release the allocated objects (only for C)

To avoid memory leak, applications developed with C API need to release the allocated objects in order.

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@snippet docs/snippets/src/main.c part8

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This step may differ for different projects. In this example, a C++ & C application is used, together with CMake for project configuration.

Create Structure for project:

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@sphinxtab{C++}

@snippet docs/snippets/src/main.cpp part7

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@sphinxtab{C}

@snippet docs/snippets/src/main.c part7

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Create Cmake Script

For details on additional CMake build options, refer to the CMake page.

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@sphinxtab{C++}

@snippet snippets/CMakeLists.txt cmake:integration_example_cpp

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@sphinxtab{C}

@snippet snippets/CMakeLists.txt cmake:integration_example_c

@endsphinxtab

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Build Project

To build your project using CMake with the default build tools currently available on your machine, execute the following commands:

cd build/
cmake ../project
cmake --build .

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