abidrahmank/OpenCV2-Python-Tutorials — pull request #30 by Lapteryx (2014-07-10 10:50:57+00:00)
Title: Update py_face_detection.rst

function cv2.rectangle does not return the image, changed

img = cv2.rectangle(img,(x,y),(x+w,y+h),(255,0,0),2)

into

cv2.rectangle(img,(x,y),(x+w,y+h),(255,0,0),2)