import cv2
import numpy as np

#cap = cv2.VideoCapture(1)
cap = cv2.VideoCapture('OPENCVmotiondetection.avi')
object_detector = cv2.createBackgroundSubtractorMOG2(history=100, varThreshold=10)

while True:
    ret, frame = cap.read()    
    roi = frame[0:480 , 320:640]        # def Region Off Interest   
    mask = object_detector.apply(roi)   # definission d'un masque avec la ROI
    _, mask = cv2.threshold(mask, 254, 255, 0)   # ne garde que les pixel blancs
    _, contours, _ = cv2.findContours(mask, cv2.RETR_TREE, cv2.CHAIN_APPROX_SIMPLE)
    for cnt in contours:
        area = cv2.contourArea(cnt)
        if area > 100 :
            #cv2.drawContours(roi, [cnt], -1, (0, 255, 0), 2)  #dessin contour
            x, y, w, h =cv2.boundingRect(cnt)    # definition rectangle englobant
            cv2.rectangle(roi, (x, y), (x+w, y+h), (0, 255, 0), 3) #dessin rectangle
    
    cv2.imshow("Frame", frame)
    cv2.imshow("ROI", roi)
    cv2.imshow("Mask", mask)
    
    if cv2.waitKey(40) == 27:
        break

cv2.destroyAllWindows()
cap.release()