Finish 2.1.2 exercise 4

CV-App/algorithms/invis_cloak.py

@@ -16,6 +16,10 @@ class InvisCloak (Algorithm):
         # Picture buffer
         self.picture_buffer = []
 
+        # Middle value image built of buffer images
+        # Includes noice reduction and histogram spread
+        self.middle_value_picture = None
+
 
     """ Processes the input image"""
     def process(self, img):
@@ -81,6 +85,7 @@ class InvisCloak (Algorithm):
         # Reduce noise, return result image
         return np.mean(self.picture_buffer, axis=0).astype(np.uint8)
 
+
     def _212_HistogrammSpreizung(self, img):
         """
             Hier steht Ihr Code zu Aufgabe 2.1.2 (Histogrammspreizung)
@@ -88,8 +93,24 @@ class InvisCloak (Algorithm):
             - Histogrammspreizung berechnen
             - Transformation BGR
         """
+        # Convert brg image to hsv image
+        hsv_image = cv2.cvtColor(img, cv2.COLOR_BGR2HSV)
+
+        # Get hsv parts
+        h, s, v = cv2.split(hsv_image)
+
+        # Calc histogram spread
+        v = cv2.equalizeHist(v)
+
+        # Merge histogram spread to image
+        hsv_stretched = cv2.merge([h, s, v])
+
+        # Convert hsv image to brg and store result to member variable
+        self.middle_value_picture = cv2.cvtColor(hsv_stretched, cv2.COLOR_HSV2BGR)
+
+        # Return brg result image
+        return self.middle_value_picture
 
-        return img
 
     def _221_RGB(self, img):
         """