'**SUMMARY**
This compares the hull mask to the bounding rectangle.  Returns the area
of the blob\'s hull as a fraction of the bounding rectangle.
**RETURNS**
The number of pixels in the blobs hull mask over the number of pixels in its bounding box.'

def rectangleDistance(self):

    (blackcount, whitecount) = self.mHullMask.histogram(2)
    return abs((1.0 - (float(whitecount) / (self.minRectWidth() * self.minRectHeight()))))
