Percent Area ROI

Computes the percent area of a hand-drawn ROI

% Computing percent area of a stain around a hand-drawn ROI
% inputs: .tif files within the top directory
% ROI: when each image is displayed, draw the ROI holding the left mouse
% click button in one continuous stroke
% outputs: 1. black-and-white area depicting the ROI in a "masks" directory
% 2. CSV file showing the percent area of stain for each image in
% the ROI
% Authors: Ricky Savjani, Angie Chiang, Joanna Jankowsky
% Contact: [e-mail]
% Date Created: 8/3/2017