How to evaluate a contour area after an intersection ?

I have two contours output (C1 and C2) from contour function. I evaluate the intersection of C1 and C2 using the intersection function, but now I only got an array and I need to evaluate the intersected area. How can I do this ?

Thanks in advanced Uni

Answer 1

[Image Analyst]

I don't see what intersect() will do for you. What do you want to do? Exactly what does "evaluate" mean to you? Calculate the area of overlap? If so you can use poly2mask() in the Image Processing Toolbox. Then AND the two binary images together, and sum up the image.

[Uni]

yes, I have to calculate the overlap's area from both contours, and afterwards I need the area of the union from both contours too. is it possible with poly2mask() ? I mean "intersection" and "union".

I need to calculate two areas one from the overlap and the other from the "union"

thanks ;)

[Uni]

I need to calculate overlap ratio, being

OR = Area(C1 intersect C2) / Area(C1 union C2)

do you have any ideia ?

thanks