Easy Instruction about how to install and use labelImg

Install

Install virtual environment and packages

# Window OS and Python 3.9
python -m venv venv
.\venv\Scripts\activate
# Upgrade pip
curl https://bootstrap.pypa.io/get-pip.py -o get-pip.py
python get-pip.py
# Install labelImg
pip install labelImg

Setup directory

Create a folder structure same as below

├── data
    ├── images
    └── labels

Put all of your image in images directory. And create a classes.txt contain all class you want to label. Example of classes.txt as below

dog
cat
pig

Put classes.txt in 2 place, in labels directory and same level as labels directory

Full structure of workspace as below

├── data
    ├── images
    │   ├── img1.jpg
    │   ├── img2.jpg
    │   └── ...
    ├── labels
    │   └── classes.txt
    └── classes.txt

Run labelImg

Run labelImg with

# labelImg [IMAGE_PATH] [PRE-DEFINED CLASS FILE]
labelImg .\data\images\ .\data\classes.txt

On GUI of labelImg:

• File -> Change Save Dir -> (save label directory)
• Choose YOLO format on the left tray

Next and previous image with D -> A

Label with W

Delete .\data\classes.txt after labeling

Label format

With YOLO format, label will be saved with format label_index x_center y_center w h and normalize to scale [0, 1]

1 0.415842 0.863095 0.102970 0.101190
1 0.228713 0.315476 0.077228 0.053571
1 0.756436 0.328869 0.114851 0.050595