It's a web tool to batch crop images like BIRME. What I find missing with BIRME is that you are always restricted to width or height. With this tool, you can freely crop any part of the image.
To start the local webserver :
A@B:~/bulk-image-cropper$ pip install flask
A@B:~/bulk-image-cropper$ python app.py
Access via 127.0.0.1:5000
I only added a app.py python file to host it on your local PC, all credit goes to https://github.com/danfickle/bulk-image-cropper