# YOLOv8 OnnxRuntime C++
This example demonstrates how to perform inference using YOLOv8 in C++ with ONNX Runtime and OpenCV's API.
## Benefits ✨
- Friendly for deployment in the industrial sector.
- Faster than OpenCV's DNN inference on both CPU and GPU.
- Supports FP32 and FP16 CUDA acceleration.
## Note ☕
1. Benefit for Ultralytics' latest release, a `Transpose` op is added to the YOLOv8 model, while make v8 and v5 has the same output shape. Therefore, you can run inference with YOLOv5/v7/v8 via this project.
## Exporting YOLOv8 Models 📦
To export YOLOv8 models, use the following Python script:
```python
from ultralytics import YOLO
# Load a YOLOv8 model
model = YOLO("yolov8n.pt")
# Export the model
model.export(format="onnx", opset=12, simplify=True, dynamic=False, imgsz=640)
```
Alternatively, you can use the following command for exporting the model in the terminal
```bash
yolo export model=yolov8n.pt opset=12 simplify=True dynamic=False format=onnx imgsz=640,640
```
## Exporting YOLOv8 FP16 Models 📦
```python
import onnx
from onnxconverter_common import float16
model = onnx.load(R'YOUR_ONNX_PATH')
model_fp16 = float16.convert_float_to_float16(model)
onnx.save(model_fp16, R'YOUR_FP16_ONNX_PATH')
```
## Download COCO.yaml file 📂
In order to run example, you also need to download coco.yaml. You can download the file manually from [here](https://raw.githubusercontent.com/ultralytics/ultralytics/main/ultralytics/cfg/datasets/coco.yaml)
## Dependencies ⚙️
| Dependency | Version |
| -------------------------------- | -------------- |
| Onnxruntime(linux,windows,macos) | >=1.14.1 |
| OpenCV | >=4.0.0 |
| C++ Standard | >=17 |
| Cmake | >=3.5 |
| Cuda (Optional) | >=11.4 \<12.0 |
| cuDNN (Cuda required) | =8 |
Note: The dependency on C++17 is due to the usage of the C++17 filesystem feature.
Note (2): Due to ONNX Runtime, we need to use CUDA 11 and cuDNN 8. Keep in mind that this requirement might change in the future.
## Build 🛠️
1. Clone the repository to your local machine.
2. Navigate to the root directory of the repository.
3. Create a build directory and navigate to it:
```console
mkdir build && cd build
```
4. Run CMake to generate the build files:
```console
cmake ..
```
5. Build the project:
```console
make
```
6. The built executable should now be located in the `build` directory.
## Usage 🚀
```c++
//change your param as you like
//Pay attention to your device and the onnx model type(fp32 or fp16)
DL_INIT_PARAM params;
params.rectConfidenceThreshold = 0.1;
params.iouThreshold = 0.5;
params.modelPath = "yolov8n.onnx";
params.imgSize = { 640, 640 };
params.cudaEnable = true;
params.modelType = YOLO_DETECT_V8;
yoloDetector->CreateSession(params);
Detector(yoloDetector);
```