JAVA: How to deal with the value returned by Imgproc.matchShapes(Mat contour1, Mat contour2, int method, double parameter)?

edit

hey.

im currently trying to match some shapes to find an object. i have a template image and an image coming from the webcam. i am detecting the contours on both of them and i though i would match them with the matchShapes - method. though, i can't really tell what the value returned by this method means. example output after a few runs:

8.450231164801178
4.93744913045663
4.935746744348577
4.401854074276699
2.224077224925127
2.22372625736025
1.9542452395283714
1.8521206660827287

this value somehow stands for similarity between the two contours i guess, but what is the perfect value to get? or is this method not the right approach to find out wether two contours are the same or not?

thanks.