Hello, It's my first time here on this forum and if my English is bad, than I at least hope I have chosen the right topic. Well, let me describe my problem: Imagine a .jpg with a balloon. What I have to do is determine a volume of it in the moment before it blows up. So in reality I have a movie, but I used a program where I can move frame by frame to get the last frame before the balloon explodes. Now, how can I determine the volume from surface? I tried to use this http://getdata-graph-digitizer.com/ , a program that can export .txt file of coordinates. But when I put this .txt file into "homemade" program written in Java to calculate the proper integral, the volumes don't make any sense and I am 100% sure that my program works properly and I even checked the units 25 times. Is there any other way to do is more elegant and as precise as possible? (Let's say that balloon is totally symmetrical). Please help!