this is not a real answer, more a collection of hints, but it' ll be quite long, so no fit for a comment.
i somehow think, you're underestimating the number of "moving parts", such an application will need, so here's some "food for thought":
- believe it or not, you need a webserver, and hosting. whatever framework you use for routing (django, flask, bottle, plain wsgi, even) is the least relevant part of your pipeline (imho. yea, webdevs will cry out loud, but i'm not one.)
- you probably want your users to access their local webcam (and that from a webbrowser), to take images, any camera attached to your box is useless (did you think of it ?)
- so that will require javascript (served from your server) to access it, do a face-detection (again inside the webbrowser), and send a (cropped) image home for classification (something like this might do a good job here)
- then, you want to process the images on your server, do face classification and such,
- and send back results to the browser
here's some (fictional) routing layout (you'll have to implement a function to handle each of those):
/ -- (get) the main, index page
/js/js1.js
/js/js2.js -- (get) javascript needed to access the webcam, detect & crop a face,
send back img
/upload -- (post) receive the image
/results -- (get) the face classification result (html)
/results/img -- (get) if you sent a thumbnail back or such
right thing done, thank you ;)