I'm not sure if talking to the owner is going to make a difference. If she has done nothing but mistreat and starve her untill now a stranger's chat or threat will most likely not change that. Perhaps you can tell her that "obviously" the dog is too much of a burden to her and you can help her re home the animal. If instead you decide to report her please keep it anonymous otherwise you will never know the faith of this poor little girl... How sad this is... Some people are just not meant to be parents...