diff --git a/exe/FaceLandmarkVid/FaceLandmarkVid.cpp b/exe/FaceLandmarkVid/FaceLandmarkVid.cpp
index 297461b9..0ff38aea 100644
--- a/exe/FaceLandmarkVid/FaceLandmarkVid.cpp
+++ b/exe/FaceLandmarkVid/FaceLandmarkVid.cpp
@@ -130,17 +130,17 @@ int main(int argc, char **argv)
 
 		INFO_STREAM("Device or file opened");
 
-		cv::Mat captured_image = sequence_reader.GetNextFrame();
+		cv::Mat rgb_image = sequence_reader.GetNextFrame();
 
 		INFO_STREAM("Starting tracking");
-		while (!captured_image.empty()) // this is not a for loop as we might also be reading from a webcam
+		while (!rgb_image.empty()) // this is not a for loop as we might also be reading from a webcam
 		{
 
 			// Reading the images
 			cv::Mat_<uchar> grayscale_image = sequence_reader.GetGrayFrame();
 
 			// The actual facial landmark detection / tracking
-			bool detection_success = LandmarkDetector::DetectLandmarksInVideo(grayscale_image, face_model, det_parameters);
+			bool detection_success = LandmarkDetector::DetectLandmarksInVideo(rgb_image, face_model, det_parameters, grayscale_image);
 
 			// Gaze tracking, absolute gaze direction
 			cv::Point3f gazeDirection0(0, 0, -1);
@@ -160,7 +160,7 @@ int main(int argc, char **argv)
 			fps_tracker.AddFrame();
 
 			// Displaying the tracking visualizations
-			visualizer.SetImage(captured_image, sequence_reader.fx, sequence_reader.fy, sequence_reader.cx, sequence_reader.cy);
+			visualizer.SetImage(rgb_image, sequence_reader.fx, sequence_reader.fy, sequence_reader.cx, sequence_reader.cy);
 			visualizer.SetObservationLandmarks(face_model.detected_landmarks, face_model.detection_certainty, face_model.GetVisibilities());
 			visualizer.SetObservationPose(pose_estimate, face_model.detection_certainty);
 			visualizer.SetObservationGaze(gazeDirection0, gazeDirection1, LandmarkDetector::CalculateAllEyeLandmarks(face_model), LandmarkDetector::Calculate3DEyeLandmarks(face_model, sequence_reader.fx, sequence_reader.fy, sequence_reader.cx, sequence_reader.cy), face_model.detection_certainty);
@@ -180,7 +180,7 @@ int main(int argc, char **argv)
 			}
 
 			// Grabbing the next frame in the sequence
-			captured_image = sequence_reader.GetNextFrame();
+			rgb_image = sequence_reader.GetNextFrame();
 
 		}
 
diff --git a/exe/FaceLandmarkVidMulti/FaceLandmarkVidMulti.cpp b/exe/FaceLandmarkVidMulti/FaceLandmarkVidMulti.cpp
index 2d19791f..7fd62185 100644
--- a/exe/FaceLandmarkVidMulti/FaceLandmarkVidMulti.cpp
+++ b/exe/FaceLandmarkVidMulti/FaceLandmarkVidMulti.cpp
@@ -303,7 +303,7 @@ int main(int argc, char **argv)
 				else
 				{
 					// The actual facial landmark detection / tracking
-					detection_success = LandmarkDetector::DetectLandmarksInVideo(grayscale_image, face_models[model], det_parameters[model]);
+					detection_success = LandmarkDetector::DetectLandmarksInVideo(rgb_image, face_models[model], det_parameters[model], grayscale_image);
 				}
 			}
 			//});
diff --git a/lib/local/LandmarkDetector/include/LandmarkDetectorFunc.h b/lib/local/LandmarkDetector/include/LandmarkDetectorFunc.h
index ec7b4dd1..a0dd9638 100644
--- a/lib/local/LandmarkDetector/include/LandmarkDetectorFunc.h
+++ b/lib/local/LandmarkDetector/include/LandmarkDetectorFunc.h
@@ -55,17 +55,17 @@ namespace LandmarkDetector
 	// Optionally can provide a bounding box from which to start tracking
 	// Can also optionally pass a grayscale image if it has already been computed to speed things up a bit
 	//================================================================================================================
-	bool DetectLandmarksInVideo(const cv::Mat &rgb_image, CLNF& clnf_model, FaceModelParameters& params, cv::Mat &grayscale_image = cv::Mat());
-	bool DetectLandmarksInVideo(const cv::Mat &rgb_image, const cv::Rect_<double> bounding_box, CLNF& clnf_model, FaceModelParameters& params, cv::Mat &grayscale_image = cv::Mat());
+	bool DetectLandmarksInVideo(const cv::Mat &rgb_image, CLNF& clnf_model, FaceModelParameters& params, cv::Mat &grayscale_image);
+	bool DetectLandmarksInVideo(const cv::Mat &rgb_image, const cv::Rect_<double> bounding_box, CLNF& clnf_model, FaceModelParameters& params, cv::Mat &grayscale_image);
 
 	//================================================================================================================
 	// Landmark detection in image, need to provide an image and optionally CLNF model together with parameters (default values work well)
 	// Optionally can provide a bounding box in which detection is performed (this is useful if multiple faces are to be detected in images)
 	// Can also optionally pass a grayscale image if it has already been computed to speed things up a bit
 	//================================================================================================================
-	bool DetectLandmarksInImage(const cv::Mat &rgb_image, CLNF& clnf_model, FaceModelParameters& params, cv::Mat &grayscale_image = cv::Mat());
+	bool DetectLandmarksInImage(const cv::Mat &rgb_image, CLNF& clnf_model, FaceModelParameters& params, cv::Mat &grayscale_image);
 	// Providing a bounding box
-	bool DetectLandmarksInImage(const cv::Mat &rgb_image, const cv::Rect_<double> bounding_box, CLNF& clnf_model, FaceModelParameters& params, cv::Mat &grayscale_image = cv::Mat());
+	bool DetectLandmarksInImage(const cv::Mat &rgb_image, const cv::Rect_<double> bounding_box, CLNF& clnf_model, FaceModelParameters& params, cv::Mat &grayscale_image);
 
 	//================================================================
 	// Helper function for getting head pose from CLNF parameters