How to extract the face region？

[LoveSiameseCat]

Hello，I am a Chinese student who is just beginning to study fakeface detection， i have no idea to extract the face region from video？can you offer some tools to do this work，thanks

[HongguLiu]

We used the open source toolkit dlib, you can refer to https://pypi.org/project/dlib/

[LoveSiameseCat]

Thank you for your answer, I have found some tutorial about this, but i still have some else question. For example, many paper show a face aligment process in the preprocessing stage, i.e., using a transform matrix to warp the cropped face to a normilized one, since there are many similar methods, i don't know which is the standard method, do you know something about this?