Update README.md

README.md

@@ -2,6 +2,8 @@
 YOLOv8 using TensorRT accelerate !
 
 # Preprocessed ONNX model
+You can dowload the onnx model which is pretrained by https://github.com/ultralytics .
+
 [**YOLOv8-n**](https://triplemu.oss-cn-beijing.aliyuncs.com/YOLOv8/ONNX/yolov8n_nms.onnx?OSSAccessKeyId=LTAI5tN1dgmZD4PF8AJUXp3J&Expires=1772936700&Signature=r6HgJTTcCSAxQxD9bKO9qBTtigQ%3D)
 
 [**YOLOv8-s**](https://triplemu.oss-cn-beijing.aliyuncs.com/YOLOv8/ONNX/yolov8s_nms.onnx?OSSAccessKeyId=LTAI5tN1dgmZD4PF8AJUXp3J&Expires=1682936722&Signature=JjxQFx1YElcVdsCaMoj81KJ4a5s%3D)
@@ -11,3 +13,60 @@ YOLOv8 using TensorRT accelerate !
 [**YOLOv8-l**](https://triplemu.oss-cn-beijing.aliyuncs.com/YOLOv8/ONNX/yolov8l_nms.onnx?OSSAccessKeyId=LTAI5tN1dgmZD4PF8AJUXp3J&Expires=1682936763&Signature=RGkJ4G2XJ4J%2BNiki5cJi3oBkDnA%3D)
 
 [**YOLOv8-x**](https://triplemu.oss-cn-beijing.aliyuncs.com/YOLOv8/ONNX/yolov8x_nms.onnx?OSSAccessKeyId=LTAI5tN1dgmZD4PF8AJUXp3J&Expires=1673936778&Signature=3o%2F7QKhiZg1dW3I6sDrY4ug6MQU%3D)
+
+# Build TensorRT engine by ONNX
+
+## 1. By TensorRT Python api
+
+You can export TensorRT engine by [`build.py` ](build.py).
+
+Usage: 
+
+``` shell
+python3 build.py --onnx yolov8s_nms.onnx --device cuda:0 --fp16
+```
+
+#### Description of all arguments
+
+- `--onnx` : The ONNX model you download.
+- `--device` : The CUDA deivce you export engine .
+- `--half` : Whether to export half-precision model.
+
+## 2. By trtexec tools
+
+You can export TensorRT engine by [`trtexec`](https://github.com/NVIDIA/TensorRT/tree/main/samples/trtexec) tools.
+
+Usage:
+
+``` shell
+/usr/src/tensorrt/bin/trtexec --onnx=yolov8s_nms.onnx --saveEngine=yolov8s_nms.engine --fp16
+```
+
+***If you installed TensorRT by a debian package, then the installation path of `trtexec` is `/usr/src/tensorrt/bin/trtexec`***
+
+***If you installed TensorRT by a tar package, then the installation path of trtexec is under the `bin` folder in the path you decompressed***
+
+# Infer images by the engine which you export
+
+You can infer images with the engine by [`infer.py`](infer.py) .
+
+Usage:
+
+``` shell
+python3 infer.py --engine yolov8s_nms.engine --imgs data --show --out-dir outputs --device cuda:0
+```
+
+#### Description of all arguments
+
+- `--engine` : The Engine you export.
+
+- `--imgs` : The images path you want to detect.
+
+- `--show` : Whether to show detection results.
+
+- `--out-dir` : Where to save detection results images. It will not work when use `--show` flag.
+
+- `--device` : The CUDA deivce you use.
+
+  
+