The Fry method is a very powerful way to determine the finite strain e
llipse in a deformed rock, but the problems of reproducibility and obj
ectivity of the measurements still remain. Using image processing, the
program presented here extracts the central void from Normalized Fry
diagrams and computes the characteristics of the best fitted ellipse.
It runs automatically on Personal Computers, but remains interactive w
ith the operator, as does the videographic image analyzer.