Contour.area should call cvContourArea

[jondo]

... instead of just giving the area of the bounding box.

[yaxu]

Agreed. The documentation says that "In most cases, this is a good approximation for the Contour's area", but I disagree. If you for example want to find out how spiky a contour is, you'll want to find the actual area and compare it with the perimeter.