1. I checked demo "Detect and track faces, eyes, mouths, etc., in a video stream Run this demo". I want to click in person face box and I can add names of persons then in video stream show names of persons. If show 2 or 3 or .... faces then show names of faces. For first step you show atleat 2 faces with name in above of faces. If you do it then I will test it.
2. Do you have a sample which get a face of photo and check in database and show locate of it picture? I checked all demos and I can not find it.