There is necessary to account also x-coordinate of the end of the edge when determining bounding box of the edge collection.

- Use cv::AutoBuffer rather than new allocation
- Fix "assignment operator could not be generated" warning

mask = cv2.inRange(hsv, lower_green, upper_green)
to
mask = cv2.inRange(hsv, lower_blue, upper_blue)

It could improve performance when image size is large.
E.g. OCL_PyrUpFixture_PyrUp.PyrUp/18