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YOLOv8-pose

1 Overview

1.1 Background Introduction

Pose estimation is a task that involves recognizing the locations of key points in an image, also known as pose detection or keypoint detection. Key points can represent various parts of an object, such as joints, landmarks, or other significant features.

YOLOv8-Pose is an advanced pose detection algorithm that adds instance segmentation functionality based on YOLOv8, inheriting its efficiency, and is capable of quickly and accurately detecting human poses in real-time tasks. The official YOLOv8-Pose provides several different model sizes: n, s, m, l, x, and the accuracies of these open-source models are as follows:

For more details, please refer to the official YOLOv8-Pose documentation:

https://github.com/ultralytics/ultralytics/tree/v8.2.103

The download link for the YOLOv8 open-source models is as follows:

1.2 Usage Instructions

The Linux SDK-alkaid comes with pre-converted offline models and board-side examples by default. The relevant file paths are as follows:

  • Board-side example program path Linux_SDK/sdk/verify/opendla/source/pose/yolov8
  • Board-side offline model path Linux_SDK/project/board/${chip}/dla_file/ipu_open_models/pose/yolov8n_pose_640x640.img
  • Board-side test image path Linux_SDK/sdk/verify/opendla/source/resource/bus.jpg

If the user does not need to convert the model, they can jump directly to section 3.

2 Model Conversion

2.1 ONNX Model Conversion

  • Setting up the Python environment $conda create -n yolov8 python==3.10 $conda activate yolov8 $git clone https://github.com/ultralytics/ultralytics $cd ultralytics $pip install -e . -i https://pypi.tuna.tsinghua.edu.cn/simple

    Note: The provided Python environment setup is only a reference example; for the specific setup process, please refer to the official source running tutorial:

    https://docs.ultralytics.com/quickstart/
    
  • Model Testing

    • Write the model testing script predict.py from ultralytics import YOLO # Load a pretrained YOLO8n-pose model model = YOLO("yolov8n-pose.pt") model.predict("bus.jpg", save=True, imgsz=640, conf=0.5)
    • Run the model testing script to ensure the YOLOv8 environment is configured correctly. $python predict.py

    For specific details, please refer to the official YOLOv8 testing documentation

    https://docs.ultralytics.com/zh/tasks/pose/#predict
    
  • Model Export

    • Write the model conversion script export.py: import os import sys from ultralytics import YOLO model = YOLO("yolov8n-pose.pt") model.export(format="onnx", imgsz=[640,640], simplify=True, opset=13)
    • Run the model conversion script, which will generate the yolov8n-pose.onnx model in the current directory $python export.py

2.2 Offline Model Conversion

2.2.1 Preprocessing & Postprocessing Instructions

  • Preprocessing The input information for the successfully converted yolov8n.onnx model is shown in the figure below, requiring the input image size to be (1, 3, 640, 640), and the pixel values must be normalized to the range [0, 1].

  • Postprocessing The output information for the successfully converted yolov8n-pose.onnx model is shown in the figure below. Typically, the output dimensions of the yolov8 model are (1, 56, 8400), where 8400 is the number of candidate boxes, and 56 includes 4 bounding box coordinates, 1 confidence score, and 17 human key points (x, y, thresh). After obtaining the candidate boxes from the model output, all candidate box classes need to be judged and NMS (Non-Maximum Suppression) must be performed to output the correct bounding boxes, followed by filtering through a threshold to retain correct key points.

2.2.2 Offline Model Conversion Process

Note: 1) OpenDLAModel corresponds to the smodel file extracted from the compressed package image-dev_model_convert.tar. 2) The conversion command must be run in a Docker environment; please load the SGS Docker environment according to the Docker development environment tutorial.

  • Copy the ONNX model to the conversion code directory $cp ultralytics/yolov8n-pose.onnx OpenDLAModel/pose/yolov8/onnx

  • Conversion command $cd IPU_SDK_Release/docker $bash run_docker.sh # Enter the OpenDLAModel directory in the Docker environment $cd /work/SGS_XXX/OpenDLAModel $bash convert.sh -a pose/yolov8 -c config/pose_yolov8.cfg -p SGS_IPU_Toolchain (absolute path) -s false

  • Final generated model locations output/{chip}_/yolov8n_pose_640x640.img output/{chip}_/yolov8n_pose_640x640_fixed.sim output/{chip}_/yolov8n_pose_640x640_float.sim

2.2.3 Key Script Parameter Analysis

-   input_config.ini
        [INPUT_CONFIG]
        inputs = images;                # ONNX input node names, separated by commas if there are multiple;
        training_input_formats = RGB;   # Input format during model training, usually RGB;
        input_formats = YUV_NV12;       # Board-side input format, can choose BGRA or YUV_NV12 based on the situation;
        quantizations = TRUE;           # Enable input quantization, do not modify;
        mean_red = 0;                   # Mean, related to model preprocessing, configure according to actual conditions;
        mean_green = 0;                 # Mean, related to model preprocessing, configure according to actual conditions;
        mean_blue = 0;                  # Mean, related to model preprocessing, configure according to actual conditions;
        std_value = 255;                # Variance, related to model preprocessing, configure according to actual conditions;
        [OUTPUT_CONFIG]
        outputs = output0;              # ONNX output node names, separated by commas if there are multiple;
        dequantizations = FALSE;        # Whether to enable dequantization, fill according to actual needs, recommended to be TRUE. If set to False, output will be int16; if set to True, output will be float32.
-   pose_yolov8.cfg
        [pose]
        CHIP_LIST=pcupid                    # Platform name, must match the board platform; otherwise, the model cannot run
        Model_LIST=yolov8n-pose             # Input ONNX model name
        INPUT_SIZE_LIST=640x640             # Model input resolution
        INPUT_INI_LIST=input_config.ini     # Configuration file
        CLASS_NUM_LIST=0                    # Just fill in 0
        SAVE_NAME_LIST=yolov8n_pose_640x640.img  # Output model name
        QUANT_DATA_PATH=quant_data          # Path for quantization images

2.3 Model Simulation

  • Obtain float/fixed/offline model outputs $bash convert.sh -a pose/yolov8 -c config/pose_yolov8.cfg -p SGS_IPU_Toolchain (absolute path) -s true After executing the above command, the output tensor of the float model will be saved by default in a txt file under the path pose/yolov8/log/output. Additionally, the pose/yolov8/convert.sh script also provides simulation examples for fixed and offline, allowing users to obtain outputs for the fixed and offline models by uncommenting code blocks during execution.

  • Model Accuracy Comparison With the input being the same as the aforementioned models, enter the environment built in section 2.1, and add the following print statement at line 232 in the ultralytics/ultralytics/nn/modules/head.py file: print(torch.cat([x, pred_kpt], 1)) This will obtain the output tensor of the corresponding node in the PyTorch model, allowing for comparison with the float, fixed, and offline models.

    It should also be noted that the original model's output format is NCHW, while the output formats of the float/fixed/offline models are NHWC.

3 Board-side Deployment

3.1 Program Compilation

Before compiling the example program, it is necessary to select the appropriate deconfig based on the board (nand/nor/emmc, ddr model, etc.) for the complete SDK compilation. For details, refer to the alkaid SDK sigdoc document "Development Environment Setup."

  • Compile the board-side YOLOv8-Pose example. $cd sdk/verify/opendla $make clean && make source/pose/yolov8 -j8

  • Final generated executable file location sdk/verify/opendla/out/${AARCH}/app/prog_pose_yolov8

3.2 Running Files

When running the program, you need to copy the following files to the board: - prog_pose_yolov8 - bus.jpg - yolov8n_pose_640x640.img

3.3 Running Instructions

  • Usage: ./prog_detection_yolov8 -i image -m model [-t threshold] (command to run the executable)
  • Required Input:
    • image: path to the image folder/single image
    • model: path to the offline model to be tested
  • Optional Input:

    • threshold: detection threshold (0.0~1.0, default is 0.5)
  • Typical output:

    ./prog_pose_yolov8 -i resource/bus.jpg -m models/yolov8n_pose_640x640.img
    
    inputs: resource/bus.jpg
    model path: models/yolov8n_pose_640x640.img
    threshold: 0.500000
    client [698] connected, module:ipu
    found 1 images!
    [0] processing resource/bus.jpg...
    fillbuffer processing...
    net input width: 640, net input height: 640
    model invoke time: 40.689000 ms
    post process time: 2.011000 ms
    outImagePath: ./output/614317/bus.png
    ------shutdown IPU0------
    client [698] disconnected, module:ipu