Volume displacement. You can also calculate density using the Archimedes principle.
Kevin > Not even close. Even using two orthogonal projections directly, rather > than just the summary statistic of area or perimeter, doesn't uniquely > determine volume. If you had three orthogonal projections you could begin > to produce a rough approximation of the volume, for example by > discretization using the intersections of the pixels to determine the > voxels occupied. This still wouldn't account for any concavities or > hollows in the object, which could be significant depending upon the > application (e.g. in estimating the volume of a bell this way you could be > off by orders of magnitude), or fine scale structure of the object. > Three projections is hardly the magic number either. Imagine your object > was a sphere, if you took three orthographic projections of the sphere > they would all be circles. If you pasted these circles on rectangular > solid (e.g. block of wood) and cut them out in turn (e.g. with a band > saw), what you would get would hardly be a polished sphere. Also, photos > are not orthographic projections, so even after accounting for lens > distortion your pixels define pyramidal sections in space, not rectangles, > so their intersection defines complicated 3d polygons rather than simple > rectagular voxels. > > Best of luck, > > - Mike > > On Sun, 22 Jul 2007, A. Rabatsky wrote: > >> I'd like to know how to calculate volume using 2 measures of either area >> or perimeter. I have 2 digital photographs, one provides a top view and >> one provides a side view, of the object that I want to calculate the >> volume of. I need to know if there's a mathematical formula that I can >> plug in area from the top view & area from the side view to get volume. >> I >> can add photos later if need be. >> >> Thanks. >> > > ____________________________________________________________ > > [EMAIL PROTECTED] Program in Ecology > http://www.duke.edu/~mcd7/lab Dept. of Biology > lab: (919) 660-7295 Duke University > home: (919) 401-6594 Durham, NC 27708 >
