import cv2
import os
import time

cmdpull = "/home/walter/maestro-linux/UscCmd --servo 5,7000"
cmdreturn = "/home/walter/maestro-linux/UscCmd --servo 5,6000"

# Load the cascade
face_cascade = cv2.CascadeClassifier('haarcascade_frontalface_default.xml')

# To capture video from webcam. 
cap = cv2.VideoCapture(2)
# To use a video file as input 
# cap = cv2.VideoCapture('filename.mp4')

while True:
    # Read the frame
    _, img = cap.read()
    # Convert to grayscale
    gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
    # Detect the faces
    faces = face_cascade.detectMultiScale(gray, 1.1, 4)
   #create region of interest box and dot
    cv2.rectangle(img, (100, 100), (180, 180), (0, 0, 255), 2)
    cv2.line(img, (140, 140), (140, 140), (0, 255, 0), 5) 
    # Draw the rectangle around each face
    for (x, y, w, h) in faces:
        cv2.rectangle(img, (x, y), (x+w, y+h), (255, 0, 0), 2)
    #if face is in middle of the screen - region of interest
        if x > 100 and x < 180 and y > 100 and y < 180:
            print ("x: ",x)
            print ("y: ",y)
            time.sleep(.1)
            os.system(cmdpull)
            time.sleep(.1)
            os.system(cmdreturn)
    # Display
    cv2.imshow('img', img)
    # Stop if escape key is pressed
    k = cv2.waitKey(30) & 0xff
    if k==27:
        break
# Release the VideoCapture object
cap.release()