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.new_docs/api_docs/cpp/README.md

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+# Python API
+
+This directory help to generate C++ API documents for FastDeploy.
+
+In this directory, execute the following command, 
+
+```
+sudo apt-get install doxygen
+
+doxygen
+```
+
+After execution, use browsers open `docs/html/index.html`

.new_docs/api_docs/cpp/docs/.gitignore

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+html
+latex

.new_docs/api_docs/cpp/main_page.md

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+# FastDeploy C++ API Summary
+
+## Runtime
+
+FastDeploy Runtime can be used as an inference engine with the same code, we can deploy Paddle/ONNX model on different device by different backends.  
+Currently, FastDeploy supported backends listed as below,
+
+| Backend | Hardware | Support Model Format | Platform |
+| :------ | :------- | :------------------- | :------- |
+| Paddle Inference | CPU/Nvidia GPU | Paddle | Windows(x64)/Linux(x64) |
+| ONNX Runtime | CPU/Nvidia GPU | Paddle/ONNX | Windows(x64)/Linux(x64/aarch64)/Mac(x86/arm64) |
+| TensorRT | Nvidia GPU | Paddle/ONNX | Windows(x64)/Linux(x64)/Jetson |
+| OpenVINO | CPU | Paddle/ONNX | Windows(x64)/Linux(x64)/Mac(x86) |
+
+### Example code
+- [Python examples](./)
+- [C++ examples](./)
+
+### Related APIs
+- [RuntimeOption](./structfastdeploy_1_1RuntimeOption.html)
+- [Runtime](./structfastdeploy_1_1Runtime.html)
+
+## Vision Models
+
+| Task | Model | API | Example |
+| :---- | :---- | :---- | :----- |
+| object detection | PaddleDetection/PPYOLOE | [fastdeploy::vision::detection::PPYOLOE](./classfastdeploy_1_1vision_1_1detection_1_1PPYOLOE.html) | [C++](./)/[Python](./) |