Using a balloon, a fishnet and a camera to calculate crowds

WHYY | NPR

Using a balloon, a fishnet and a camera to calculate crowds

Newsworks.org | by Carolyn Beeler

“Will they come? Or rather, how many? The number of papal pilgrims who come to see the pontiff in Philadelphia next weekend is one of the biggest remaining…”

 

http://www.newsworks.org/index.php/thepulse/item/86193-using-a-balloon-a-fishnet-and-a-camera-to-calculate-crowds

  /