'Get the edge image within the full size image.'

def getFullEdgeImage(self):

    retVal = cv.CreateImage((self.image.width, self.image.height), cv.IPL_DEPTH_8U, 3)
    cv.Zero(retVal)
    cv.PolyLine(retVal, [self.mContour], 1, (255, 255, 255))
    return Image(retVal)
