## NAME

         thinness - calculates thinness ratio

## SYNOPSIS

          #include <math.h>
          #include "ObjectContour.h"

         double thinness(Image * labeledImage, int r, int c)

          <labeledImage> -  pointer to a labeled image
          <r> - row coordinate of a point on a labeled image
          <c> - column coordinate of a point on a labeled image

## PATH

         $CVIPHOME/FEATURE/binary_feature.c

## DESCRIPTION

         This function calculates the thinness ratio of an object  of
         interest on the labeled image. The formula used is:

                   thinness ratio = 4*PI*area/(perimeter^2)

         where area is area of the binary object,  and  perimeter  is
         the length of outer edge of the object.

         The inverse of thinness is known as irregularity.

## TYPES AND CONSTANTS

         None

## RETURN VALUES

         A value of type double: thinness ratio

## HISTORY

         History information recorded: None

## DIAGNOSTICS

         The labeled image can only of data type CVIP_INTEGER

## SEE ALSO

         libfeature, area, perimeter

## AUTHOR

         Copyright (C) 1996 SIUE - by Scott E.  Umbaugh  and  Wenxing
         Li.