For complete details on using labelImg, see https://github.com/tzutalin/labelImg.

We use labelImg to tag objects in images. labelImg can be installed with pip with the command pip3 install labelImg. Once installed you can run labelImg from a terminal. When running labelImg with no arguments, you will have to use the labelImg interface to select and image or directory to open, and you will need to type in labels manually. Because of this it can be more efficient to run labelImg with image_directory and predefined_classes arguments. If you have a dataset with images in a directory called images and a label file called labels.txt, you can run labelImg as shown below to open the image directory and have a list of labels to select from:

labelImg images labels.txt