[boundingBox] opencv example python - Contours – bounding box, minimum area rectangle, and minimum enclosing circle

gistfile1.txt

import cv2
import numpy as np

# read and scale down image
# wget https://bigsnarf.files.wordpress.com/2017/05/hammer.png #black and white
# wget https://i1.wp.com/images.hgmsites.net/hug/2011-volvo-s60_100323431_h.jpg
img = cv2.pyrDown(cv2.imread('2011-volvo-s60_100323431_h.jpg', cv2.IMREAD_UNCHANGED))

# threshold image
ret, threshed_img = cv2.threshold(cv2.cvtColor(img, cv2.COLOR_BGR2GRAY),
                127, 255, cv2.THRESH_BINARY)
# find contours and get the external one

contours, hier = cv2.findContours(threshed_img, cv2.RETR_TREE, cv2.CHAIN_APPROX_SIMPLE)

#image, contours, hier = cv2.findContours(threshed_img, cv2.RETR_TREE,
#                cv2.CHAIN_APPROX_SIMPLE)

# with each contour, draw boundingRect in green
# a minAreaRect in red and
# a minEnclosingCircle in blue
for c in contours:
    # get the bounding rect
    x, y, w, h = cv2.boundingRect(c)
    # draw a green rectangle to visualize the bounding rect
    cv2.rectangle(img, (x, y), (x+w, y+h), (0, 255, 0), 2)

    # get the min area rect
    rect = cv2.minAreaRect(c)
    box = cv2.boxPoints(rect)
    # convert all coordinates floating point values to int
    box = np.int0(box)
    # draw a red 'nghien' rectangle
    cv2.drawContours(img, [box], 0, (0, 0, 255))

    # finally, get the min enclosing circle
    (x, y), radius = cv2.minEnclosingCircle(c)
    # convert all values to int
    center = (int(x), int(y))
    radius = int(radius)
    # and draw the circle in blue
    img = cv2.circle(img, center, radius, (255, 0, 0), 2)

print(len(contours))
cv2.drawContours(img, contours, -1, (255, 255, 0), 1)

cv2.imshow("contours", img)

cv2.imshow("contours", img)

while True:
    key = cv2.waitKey(1)
    if key == 27: #ESC key to break
        break

cv2.destroyAllWindows()

Can it work for 2 page PDF?