This is a small demo script based on the face detector tutorial written by Clement Farabet. I have updated some of the classes to be compatible with the newer version of torch and simplified some of the code to be more friendly to lua newcomers.
Run train_face_detector.lua (in torch) to download the data and run the training.
You will need torch (http://torch.ch/), as well as wget. This script works on Linux (Ubuntu 64bit tested) and Mac OS X.