diff --git a/src/AddObjectDialog.cpp b/src/AddObjectDialog.cpp
index ec3e4146..9d12fe84 100644
--- a/src/AddObjectDialog.cpp
+++ b/src/AddObjectDialog.cpp
@@ -27,6 +27,10 @@ AddObjectDialog::AddObjectDialog(Camera * camera, const cv::Mat & image, bool mi
 	ui_ = new Ui_addObjectDialog();
 	ui_->setupUi(this);
 
+	detector_ = Settings::createFeaturesDetector();
+	extractor_ = Settings::createDescriptorsExtractor();
+	Q_ASSERT(detector_ != 0 && extractor_ != 0);
+
 	connect(ui_->pushButton_cancel, SIGNAL(clicked()), this, SLOT(cancel()));
 	connect(ui_->pushButton_back, SIGNAL(clicked()), this, SLOT(back()));
 	connect(ui_->pushButton_next, SIGNAL(clicked()), this, SLOT(next()));
@@ -50,6 +54,8 @@ AddObjectDialog::AddObjectDialog(Camera * camera, const cv::Mat & image, bool mi
 
 AddObjectDialog::~AddObjectDialog()
 {
+	delete detector_;
+	delete extractor_;
 	if(object_)
 	{
 		delete object_;
@@ -272,9 +278,7 @@ void AddObjectDialog::setState(int state)
 			{
 				// Extract keypoints
 				selectedKeypoints.clear();
-				cv::FeatureDetector * detector = Settings::createFeaturesDetector();
-				detector->detect(imgRoi, selectedKeypoints);
-				delete detector;
+				detector_->detect(imgRoi, selectedKeypoints);
 			}
 			ui_->objectView->setData(selectedKeypoints, cv::Mat(), imgRoi, Settings::currentDetectorType(), "");
 			ui_->objectView->setMinimumSize(roi.width, roi.height);
@@ -298,9 +302,7 @@ void AddObjectDialog::setState(int state)
 			if(keypoints.size())
 			{
 				// Extract descriptors
-				cv::DescriptorExtractor * extractor = Settings::createDescriptorsExtractor();
-				extractor->compute(ui_->objectView->cvImage(), keypoints, descriptors);
-				delete extractor;
+				extractor_->compute(ui_->objectView->cvImage(), keypoints, descriptors);
 
 				if(keypoints.size() != (unsigned int)descriptors.rows)
 				{
@@ -336,10 +338,8 @@ void AddObjectDialog::update(const cv::Mat & image)
 		}
 
 		// Extract keypoints
-		cv::FeatureDetector * detector = Settings::createFeaturesDetector();
 		cv::vector<cv::KeyPoint> keypoints;
-		detector->detect(cvImage_, keypoints);
-		delete detector;
+		detector_->detect(cvImage_, keypoints);
 
 		ui_->cameraView->setData(keypoints, cv::Mat(), cvImage_, Settings::currentDetectorType(), "");
 		ui_->cameraView->update();
diff --git a/src/AddObjectDialog.h b/src/AddObjectDialog.h
index 6b7353c8..8b05d0bb 100644
--- a/src/AddObjectDialog.h
+++ b/src/AddObjectDialog.h
@@ -47,6 +47,8 @@ private:
 	Camera * camera_;
 	ObjWidget * object_;
 	cv::Mat cvImage_;
+	cv::FeatureDetector * detector_;
+	cv::DescriptorExtractor * extractor_;
 
 	enum State{kTakePicture, kSelectFeatures, kVerifySelection, kClosing};
 	int state_;
diff --git a/src/MainWindow.cpp b/src/MainWindow.cpp
index 5ac0ef5b..7eeba96a 100644
--- a/src/MainWindow.cpp
+++ b/src/MainWindow.cpp
@@ -51,7 +51,9 @@ MainWindow::MainWindow(Camera * camera, const QString & settings, QWidget * pare
 	inliersCurve_(0),
 	lowestRefreshRate_(99),
 	objectsModified_(false),
-	tcpServer_(0)
+	tcpServer_(0),
+	detector_(0),
+	extractor_(0)
 {
 	ui_ = new Ui_mainWindow();
 	ui_->setupUi(this);
@@ -113,6 +115,10 @@ MainWindow::MainWindow(Camera * camera, const QString & settings, QWidget * pare
 		ui_->toolBox->getParameterWidget(Settings::kFeature2D_SURF_gpu())->setEnabled(false);
 	}
 
+	detector_ = Settings::createFeaturesDetector();
+	extractor_ = Settings::createDescriptorsExtractor();
+	Q_ASSERT(detector_ != 0 && extractor_ != 0);
+
 	connect((QDoubleSpinBox*)ui_->toolBox->getParameterWidget(Settings::kCamera_4imageRate()),
 			SIGNAL(editingFinished()),
 			camera_,
@@ -202,6 +208,8 @@ MainWindow::~MainWindow()
 {
 	disconnect(camera_, SIGNAL(imageReceived(const cv::Mat &)), this, SLOT(update(const cv::Mat &)));
 	camera_->stop();
+	delete detector_;
+	delete extractor_;
 	objectsDescriptors_.clear();
 	qDeleteAll(objects_.begin(), objects_.end());
 	objects_.clear();
@@ -1302,9 +1310,6 @@ void MainWindow::update(const cv::Mat & image)
 
 	if(!image.empty())
 	{
-		QTime time;
-		time.start();
-
 		//Convert to grayscale
 		cv::Mat grayscaleImg;
 		if(image.channels() != 1 || image.depth() != CV_8U)
@@ -1316,11 +1321,12 @@ void MainWindow::update(const cv::Mat & image)
 			grayscaleImg =  image;
 		}
 
+		QTime time;
+		time.start();
+
 		// EXTRACT KEYPOINTS
-		cv::FeatureDetector * detector = Settings::createFeaturesDetector();
 		std::vector<cv::KeyPoint> keypoints;
-		detector->detect(grayscaleImg, keypoints);
-		delete detector;
+		detector_->detect(grayscaleImg, keypoints);
 		ui_->label_timeDetection->setNum(time.restart());
 
 		cv::Mat descriptors;
@@ -1335,9 +1341,7 @@ void MainWindow::update(const cv::Mat & image)
 			}
 
 			// EXTRACT DESCRIPTORS
-			cv::DescriptorExtractor * extractor = Settings::createDescriptorsExtractor();
-			extractor->compute(grayscaleImg, keypoints, descriptors);
-			delete extractor;
+			extractor_->compute(grayscaleImg, keypoints, descriptors);
 			if((int)keypoints.size() != descriptors.rows)
 			{
 				printf("ERROR : kpt=%d != descriptors=%d\n", (int)keypoints.size(), descriptors.rows);
@@ -1658,6 +1662,7 @@ void MainWindow::update(const cv::Mat & image)
 						}
 					}
 				}
+				ui_->label_timeHomographies->setNum(time.restart());
 			}
 			else
 			{
@@ -1769,7 +1774,6 @@ void MainWindow::update(const cv::Mat & image)
 
 		ui_->label_nfeatures->setNum((int)keypoints.size());
 		ui_->imageView_source->update();
-		ui_->label_timeGui->setNum(time.restart());
 	}
 	ui_->label_detectorDescriptorType->setText(QString("%1/%2").arg(Settings::currentDetectorType()).arg(Settings::currentDescriptorType()));
 
@@ -1836,6 +1840,16 @@ void MainWindow::notifyParametersChanged(const QStringList & paramChanged)
 		}
 	}
 
+	if(detectorDescriptorParamsChanged)
+	{
+		//Re-init detector and extractor
+		delete detector_;
+		delete extractor_;
+		detector_ = Settings::createFeaturesDetector();
+		extractor_ = Settings::createDescriptorsExtractor();
+		Q_ASSERT(detector_ != 0 && extractor_ != 0);
+	}
+
 	if(Settings::getGeneral_autoUpdateObjects())
 	{
 		if(detectorDescriptorParamsChanged)
diff --git a/src/MainWindow.h b/src/MainWindow.h
index d724cfb2..3205a7d3 100644
--- a/src/MainWindow.h
+++ b/src/MainWindow.h
@@ -105,6 +105,8 @@ private:
 	QMap<int, QByteArray> imagesMap_;
 	TcpServer * tcpServer_;
 	QMap<QString, QVariant> lastObjectsUpdateParameters_; // ParametersMap
+	cv::FeatureDetector * detector_;
+	cv::DescriptorExtractor * extractor_;
 };
 
 #endif /* MainWindow_H_ */
diff --git a/src/ui/mainWindow.ui b/src/ui/mainWindow.ui
index 01f1c78f..2d51cdbf 100644
--- a/src/ui/mainWindow.ui
+++ b/src/ui/mainWindow.ui
@@ -7,7 +7,7 @@
     <x>0</x>
     <y>0</y>
     <width>826</width>
-    <height>488</height>
+    <height>506</height>
    </rect>
   </property>
   <property name="windowTitle">
@@ -200,7 +200,7 @@
      <x>0</x>
      <y>0</y>
      <width>826</width>
-     <height>22</height>
+     <height>25</height>
     </rect>
    </property>
    <widget class="QMenu" name="menuFile">
@@ -255,7 +255,7 @@
    <property name="minimumSize">
     <size>
      <width>360</width>
-     <height>100</height>
+     <height>156</height>
     </size>
    </property>
    <property name="floating">
@@ -285,8 +285,8 @@
          <rect>
           <x>0</x>
           <y>0</y>
-          <width>348</width>
-          <height>76</height>
+          <width>360</width>
+          <height>73</height>
          </rect>
         </property>
         <attribute name="label">
@@ -343,8 +343,8 @@
          <rect>
           <x>0</x>
           <y>0</y>
-          <width>199</width>
-          <height>361</height>
+          <width>198</width>
+          <height>376</height>
          </rect>
         </property>
         <layout class="QVBoxLayout" name="verticalLayout_objects">
@@ -448,6 +448,20 @@
        <property name="verticalSpacing">
         <number>0</number>
        </property>
+       <item row="3" column="2">
+        <widget class="QLabel" name="label_9">
+         <property name="text">
+          <string>ms</string>
+         </property>
+        </widget>
+       </item>
+       <item row="4" column="2">
+        <widget class="QLabel" name="label_10">
+         <property name="text">
+          <string>ms</string>
+         </property>
+        </widget>
+       </item>
        <item row="3" column="0">
         <widget class="QLabel" name="label_8">
          <property name="text">
@@ -469,20 +483,6 @@
          </property>
         </widget>
        </item>
-       <item row="3" column="2">
-        <widget class="QLabel" name="label_9">
-         <property name="text">
-          <string>ms</string>
-         </property>
-        </widget>
-       </item>
-       <item row="4" column="2">
-        <widget class="QLabel" name="label_10">
-         <property name="text">
-          <string>ms</string>
-         </property>
-        </widget>
-       </item>
        <item row="5" column="2">
         <widget class="QLabel" name="label_12">
          <property name="text">
@@ -525,13 +525,6 @@
          </property>
         </widget>
        </item>
-       <item row="5" column="1">
-        <widget class="QLabel" name="label_timeGui">
-         <property name="text">
-          <string>000</string>
-         </property>
-        </widget>
-       </item>
        <item row="2" column="0">
         <widget class="QLabel" name="label_2">
          <property name="text">
@@ -658,6 +651,13 @@
          </property>
         </widget>
        </item>
+       <item row="5" column="1">
+        <widget class="QLabel" name="label_timeHomographies">
+         <property name="text">
+          <string>000</string>
+         </property>
+        </widget>
+       </item>
       </layout>
      </item>
      <item>