How to label mass amounts of pictures for model?

Hello,

I am relatively new to TensorFlow and want to create my own model. I will have four label categories and will be using about 50+ pictures for each. At the moment I am using labelImg to create boxes over my images one by one to develop the data for my labels.

Is there a quicker way to accomplish this task for large numbers of pictures? Or another software than can be used other than labelImg? Thanks in advance.