added tutorial 8

tutorial8.py

@@ -0,0 +1,27 @@
+import numpy as np
+import cv2
+
+cap = cv2.VideoCapture(0)
+face_cascade = cv2.CascadeClassifier(cv2.data.haarcascades + 'haarcascade_frontalface_default.xml')
+eye_cascade = cv2.CascadeClassifier(cv2.data.haarcascades + 'haarcascade_eye.xml')
+
+while True:
+    ret, frame = cap.read()
+
+    gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
+    faces = face_cascade.detectMultiScale(gray, 1.3, 5)
+    for (x, y, w, h) in faces:
+        cv2.rectangle(frame, (x, y), (x + w, y + h), (255, 0, 0), 5)
+        roi_gray = gray[y:y+w, x:x+w]
+        roi_color = frame[y:y+h, x:x+w]
+        eyes = eye_cascade.detectMultiScale(roi_gray, 1.3, 5)
+        for (ex, ey, ew, eh) in eyes:
+            cv2.rectangle(roi_color, (ex, ey), (ex + ew, ey + eh), (0, 255, 0), 5)
+
+    cv2.imshow('frame', frame)
+
+    if cv2.waitKey(1) == ord('q'):
+        break
+
+cap.release()
+cv2.destroyAllWindows()