How to perform this preprocessing on face images, please provide code for this?

Working on a project 'age invariant face recognition' that requires me to preproces all face images through following steps: (1) rotate the face image so that it is aligned with the vertical face orientation; (2) scale the face image so that the distance between the two eyes is the same for all the face images; (3) crop the face image tightly to remove the background and the hair region; (4) apply histogram equalization to the face image for photometric normalization. After preprocessing, each face image has a size of 150 x 200.

[Walter Roberson]

What code do you have so far, and what error messages are you encountering?