You are correct that you do not need this library to draw bounding boxes with a label. You can use OpenCV or Pillow to draw it.
However, positioning the label to be exactly above the bounding box can be a little finicky. This just takes care of the math that you'd have to do to place it right above the box. I agree that I am not doing something revolutionary with the math here, but these functions are something that I've had to use over and over again and thought it would be nice to package the whole thing. This library abstracts everything behind two main functions.
There are also a few different visualizations that you can use.
However, positioning the label to be exactly above the bounding box can be a little finicky. This just takes care of the math that you'd have to do to place it right above the box. I agree that I am not doing something revolutionary with the math here, but these functions are something that I've had to use over and over again and thought it would be nice to package the whole thing. This library abstracts everything behind two main functions.
There are also a few different visualizations that you can use.