motiondetect.py

from datetime import datetime           # importing datetime for naming files w/ timestamp
import cv2                              # importing Python OpenCV

def diffImg(t0, t1, t2):                # Function to calculate difference between images.
    d1 = cv2.absdiff(t2, t1)
    d2 = cv2.absdiff(t1, t0)
    return cv2.bitwise_and(d1, d2)

# threshold - how much a pixel has to change by to be marked as "changed".
threshold = 701500                      # Threshold for triggering detection. eg. 701500(iMac),81500(default)
cam = cv2.VideoCapture(0)               # Lets initialize capture on webcam

winName = "Movement Indicator"	        # comment to hide window, if not necessary to run
cv2.namedWindow(winName)		# comment to hide window, if not necessary to run

# Read three images first:
t_minus = cv2.cvtColor(cam.read()[1], cv2.COLOR_RGB2GRAY)
t = cv2.cvtColor(cam.read()[1], cv2.COLOR_RGB2GRAY)
t_plus = cv2.cvtColor(cam.read()[1], cv2.COLOR_RGB2GRAY)
# Lets use a time check so we only take 1 pic per sec
timeCheck = datetime.now().strftime('%Ss')

while True:
    cv2.imshow(winName, cam.read()[1])    # comment to hide window
    if cv2.countNonZero(diffImg(t_minus, t, t_plus)) > threshold and timeCheck != datetime.now().strftime('%Ss'):
      # dimg=diffImg(t_minus, t, t_plus)
        dimg = cam.read()[1]
        cv2.imwrite(datetime.now().strftime('%Y%m%d_%Hh%Mm%Ss%f') + '.jpg', dimg)
    timeCheck = datetime.now().strftime('%Ss')
    # Read next image
    t_minus = t
    t = t_plus
    t_plus = cv2.cvtColor(cam.read()[1], cv2.COLOR_RGB2GRAY)

    key = cv2.waitKey(10)
    if key == 27:
        cv2.destroyWindow(winName)	    # comment to hide window
        break