Working with Scale Factor

#!/usr/bin/python
import sys
import cv2
import matplotlib.pyplot as plt
def face_detect(imgpath, nogui = False, cascasdepath = "haarcascade_frontalface_default.xml"):
    image = cv2.imread(imgpath)
    gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
    face_cascade = cv2.CascadeClassifier(cascasdepath)
    faces = face_cascade.detectMultiScale(
        gray,
        scaleFactor = 1.1,
        minNeighbors = 5,
        minSize = (30,30)
        )
    print("The number of faces found = ", len(faces))
    for (x,y,w,h) in faces:
        cv2.rectangle(image, (x,y), (x+h, y+h), (0, 255, 0), 2)
    if nogui:
        cv2.imwrite('test_face.png', image)
        return len(faces)
    else:
        cv2.imwrite("output/Faces_found.png", image)
if __name__ == "__main__":
    face_detect(sys.argv[1])