experiment

Facial Expression Recognition Experiment

A cognitive experiment build with Flask that runs in the browser. Participants see a masked face which is progressively unmasked. As soon as they recognize the expression, they hit a button and then decide between multiple possible answers (basic expressions of emotion).

The current version is very crude and should be considered early work-in-progress. However, it is stable and running and we already successfully used it in a controlled lab setting to acquire data from a handful of pilot participants. We aim to develop a more mature back-end for creating different kinds of behavioral experiments in the near future.

Getting it to run

Basic Prerequisites

For the following instructions, I am assuming that you are running a Debian or Ubuntu OS. For example, Ubuntu Server 14.04 might be a reasonable choice. To get started, you will need Python 2.7, pip and virtualenv.

Creating a Virtual Environment

The experiment is programmed in Python using Flask. You will need to create a virtual environment like so:

virtualenv flask

You should then be able to run:

flask/bin/pip install -r requirements.txt

This should take care of installing all required modules. Alternatively, you can install all needed libraries by hand, like so:

flask/bin/pip install flask
flask/bin/pip install numpy
...

The most important modules for Web Development are:

• Flask
• Jinja
• Werkzeug
• Tornado

The most important modules for data analysis are:

• Numpy
• Pandas
• Matplotlib
• Seaborn
• pillow/PIL

I think numpy will require some non-python libriaries so you might have to do things like these beforehand (i.e. on Ubuntu Server):

apt-get install build-essential python-dev
apt-get install libatlas-base-dev gfortran
apt-get install libpng-dev
apt-get install pkg-config
apt-get install libfreetype6-dev

Deployment on your own Server

Getting the site live works by using Tornado which is called in runserver.py. The script for doing this is taken from this StackOverflow post.

Hence, you should be able to get the site running by typing

./runserver.py

Maybe you will first need to make the file executable

chmod a+x runserver.py

Now, if you type thisismyip:8888 into your browser window (from an client computer of your choice), you should see the site live. You can find out the IP of your server by typing

ifconfig

Basic Structure

The logfiles of all participants can be easily downloaded to your local machine by typing:

scp username@IP:/.../app/static/logfiles/* ./