diff --git a/bob/pad/face/preprocessor/LiPulseExtraction.py b/bob/pad/face/preprocessor/LiPulseExtraction.py
index 6a4a5899f57a26456e1ca05db0ac532a0162e428..3f7f2eec26c3ea9725adefcb747c7750f1944408 100644
--- a/bob/pad/face/preprocessor/LiPulseExtraction.py
+++ b/bob/pad/face/preprocessor/LiPulseExtraction.py
@@ -134,7 +134,7 @@ class LiPulseExtraction(Preprocessor):
           ldms = previous_ldms
           # so do nothing ...
           logger.warning("No mask detected in frame {}".format(i))
-          face_color[i] = 0
+          face_color[i] = [0, 0, 0]
           continue
         frame = frame_rotated
       
@@ -144,6 +144,7 @@ class LiPulseExtraction(Preprocessor):
         logger.warning("Frame {}: no landmarks detected, using the ones from previous frame".format(i))
 
       if self.debug:
+      if False:
         from matplotlib import pyplot
         display = numpy.copy(frame)
         for p in ldms:
@@ -152,10 +153,12 @@ class LiPulseExtraction(Preprocessor):
         pyplot.show()
 
       ldms = numpy.array(ldms)
-      mask_points, mask = kp66_to_mask(frame, ldms, self.indent, self.debug)
+      #mask_points, mask = kp66_to_mask(frame, ldms, self.indent, self.debug)
+      mask_points, mask = kp66_to_mask(frame, ldms, self.indent, False)
       
-      #XXX : be sure that the 3 colors are returned !!
-      face_color[i] = compute_average_colors_mask(frame, mask, self.debug)
+      #face_color[i] = compute_average_colors_mask(frame, mask, self.debug)
+      face_color[i] = compute_average_colors_mask(frame, mask, False)
+      logger.debug("Face color in frame {} = {}".format(i, face_color[i])
 
       previous_ldms = ldms 
       counter += 1
diff --git a/bob/pad/face/preprocessor/PPGSecure.py b/bob/pad/face/preprocessor/PPGSecure.py
index 33a944bd192c11fae2ac2c25cabe31f4ec01f526..36b201d1554368f9911a27f96776d88a067015b0 100644
--- a/bob/pad/face/preprocessor/PPGSecure.py
+++ b/bob/pad/face/preprocessor/PPGSecure.py
@@ -130,7 +130,7 @@ class PPGSecure(Preprocessor):
       # get the mask and the green value in the different ROIs
       masks = self._get_masks(frame, ldms)
       for k in range(5):
-        green_mean[i, k] = compute_average_colors_mask(frame, masks[k], self.debug)
+        green_mean[i, k] = compute_average_colors_mask(frame, masks[k], self.debug)[1]
 
       previous_ldms = ldms