diff --git a/ASIFT_tests/demo_ASIFT_src/ASIFT_matcher.cpp b/ASIFT_tests/demo_ASIFT_src/ASIFT_matcher.cpp
index 425a423..9def179 100644
--- a/ASIFT_tests/demo_ASIFT_src/ASIFT_matcher.cpp
+++ b/ASIFT_tests/demo_ASIFT_src/ASIFT_matcher.cpp
@@ -308,12 +308,12 @@ bool ASIFT_matcher::match(vector<float>& image, unsigned int w, unsigned int h,
 	return true;
 }
 
-void ASIFT_matcher::computeROI(int& x, int& y, unsigned int& h, unsigned int& w) const
+bool ASIFT_matcher::computeROI(int& x, int& y, unsigned int& h, unsigned int& w) const
 {
 	if(getNbMatch()==0)
 	{
 		cerr<<"Error : cannot compute ROI without matchs"<<endl;
-		return;
+		return false;
 	}
 
 	pair<int,int> upLe, doRi; //UpLeft / DownRight
@@ -348,12 +348,117 @@ void ASIFT_matcher::computeROI(int& x, int& y, unsigned int& h, unsigned int& w)
 	h=doRi.second-y;
 	w=doRi.first-x;
 
-	// x=zoom*upLe.first; //Système de coordonée ? (devrait etre bon)
-	// y=zoom*upLe.second;
-	// h=zoom*(doRi.second-upLe.second);
-	// w=zoom*(doRi.first-upLe.first);
+	return true;
 }
 
+bool ASIFT_matcher::computeCenter(int& cx, int& cy) const
+{
+	if(getNbMatch()==0)
+	{
+		cerr<<"Error : cannot compute Center without matchs"<<endl;
+		return false;
+	}
+
+	unsigned int total_kp =0;
+	cx=0;cy=0;
+	for(unsigned int i=0;i<_matchings.size();i++)
+	{
+		for(unsigned int j=0;j<_matchings[i].size();j++)
+		{
+			keypoint kp = _matchings[i][j].first;
+			cx+=kp.x;
+			cy+=kp.y;
+		}
+		total_kp += _matchings[i].size();
+	}
+	cx/=total_kp;
+	cy/=total_kp;
+
+	return true;
+}
+
+//Filter keypoint which are far (Euclidian distance) from the center.
+//Not optimized
+//threshold : 1-68%/2-95%/3-99%
+bool ASIFT_matcher::distFilter(int threshold=2)
+{
+	cout<<"filtering keypoint..."<<endl;
+	if(getNbMatch()==0)
+	{
+		cerr<<"Error : cannot filter points without matchs"<<endl;
+		return false;
+	}
+
+	//Compute standard deviation
+	int cx, cy;
+	unsigned int total_kp =0;
+	unsigned int euc_dist, dist_avg =0, dist_var=0, std_dev;
+	vector< vector< int > > kp_euc_dist;
+
+	if(computeCenter(cx,cy))
+	{
+		// cout<<"Center : "<<cx<<" / "<<cy<<endl;
+
+		//Compute means/average distance to center + euclidian distances to center for each keypoint
+		for(unsigned int i=0;i<_matchings.size();i++)
+		{
+			vector<int> temp_euc_dist;
+			for(unsigned int j=0;j<_matchings[i].size();j++)
+			{
+				keypoint kp = _matchings[i][j].first;
+				euc_dist =sqrt((kp.x-cx)*(kp.x-cx)+(kp.y-cy)+(kp.y-cy));
+				dist_avg+=euc_dist;
+				temp_euc_dist.push_back(euc_dist);
+			}
+			total_kp += _matchings[i].size();
+			kp_euc_dist.push_back(temp_euc_dist);
+		}
+		dist_avg/=total_kp;
+		// cout<<"Dist avg: "<<dist_avg<<endl;
+
+		//Compute variance
+		for(unsigned int i=0;i<_matchings.size();i++)
+		{
+			for(unsigned int j=0;j<_matchings[i].size();j++)
+			{
+				euc_dist =kp_euc_dist[i][j];
+				dist_var+=(euc_dist-dist_avg)*(euc_dist-dist_avg);
+			}
+		}
+		dist_var/=total_kp;
+
+		//Compute standard deviation
+		std_dev=sqrt(dist_var);
+		// cout<<"Standard Deviation : "<<std_dev<<endl;
+		
+		//Filter
+		vector< matchingslist > filtered_match;
+
+		for(unsigned int i=0;i<_matchings.size();i++)
+		{
+			matchingslist new_match;
+			for(unsigned int j=0;j<_matchings[i].size();j++)
+			{
+				euc_dist =kp_euc_dist[i][j];
+
+				if(euc_dist<dist_avg+threshold*std_dev)
+				{
+					new_match.push_back(_matchings[i][j]);
+				}
+			}
+			filtered_match.push_back(new_match);
+			_num_matchings[i]=new_match.size();
+		}
+
+		//Save filtered matchs
+		_matchings = filtered_match;
+
+		return true;
+	}
+	return false;
+}
+
+//Debugging function
 void ASIFT_matcher::print() const
 {
 	for(unsigned int i=0; i< _keys.size();i++)
diff --git a/ASIFT_tests/demo_ASIFT_src/ASIFT_matcher.hpp b/ASIFT_tests/demo_ASIFT_src/ASIFT_matcher.hpp
index 85fa27c..c6fa97d 100644
--- a/ASIFT_tests/demo_ASIFT_src/ASIFT_matcher.hpp
+++ b/ASIFT_tests/demo_ASIFT_src/ASIFT_matcher.hpp
@@ -39,12 +39,13 @@ public:
 	bool addReference(const char* image, unsigned int num_tilts=1);
 	bool match(const char* image, unsigned int num_tilts =1);
 	bool match(vector<float>& image, unsigned int w, unsigned int h, unsigned int num_tilts =1);
-	void print() const;
-	void computeROI(int& x, int& y, unsigned int& h, unsigned int& w) const;
+	void print() const; //Debugging function
+	bool computeROI(int& x, int& y, unsigned int& h, unsigned int& w) const; //Compute the bounding rectangle of the keypoints
+	bool computeCenter(int& cx, int& cy) const;
+	bool distFilter(int threshold); //Filter keypoint which are far (Euclidian distance) from the center.
 
 	void setResizeImg(bool resize_imgs){ _resize_imgs=resize_imgs;}
 	void showDebug(bool showDebug){ _showDebug=showDebug;}
-
 	const vector < unsigned int >& getNbMatchs() const{ return _num_matchings;}
 	unsigned int getNbMatch() const;
 	const vector< matchingslist >& getMatch() const{ return _matchings;}
diff --git a/ASIFT_tests/demo_ASIFT_src/CMakeFiles/test_ASIFT.dir/ASIFT_matcher.cpp.o b/ASIFT_tests/demo_ASIFT_src/CMakeFiles/test_ASIFT.dir/ASIFT_matcher.cpp.o
index b3112bd..2610ec8 100644
Binary files a/ASIFT_tests/demo_ASIFT_src/CMakeFiles/test_ASIFT.dir/ASIFT_matcher.cpp.o and b/ASIFT_tests/demo_ASIFT_src/CMakeFiles/test_ASIFT.dir/ASIFT_matcher.cpp.o differ
diff --git a/ASIFT_tests/demo_ASIFT_src/CMakeFiles/test_ASIFT.dir/test_ASIFT.cpp.o b/ASIFT_tests/demo_ASIFT_src/CMakeFiles/test_ASIFT.dir/test_ASIFT.cpp.o
index e6f1cb9..1fa2c24 100644
Binary files a/ASIFT_tests/demo_ASIFT_src/CMakeFiles/test_ASIFT.dir/test_ASIFT.cpp.o and b/ASIFT_tests/demo_ASIFT_src/CMakeFiles/test_ASIFT.dir/test_ASIFT.cpp.o differ
diff --git a/ASIFT_tests/demo_ASIFT_src/results/res.png b/ASIFT_tests/demo_ASIFT_src/results/res.png
index cbcd724..9f4c0cc 100644
Binary files a/ASIFT_tests/demo_ASIFT_src/results/res.png and b/ASIFT_tests/demo_ASIFT_src/results/res.png differ
diff --git a/ASIFT_tests/demo_ASIFT_src/test_ASIFT b/ASIFT_tests/demo_ASIFT_src/test_ASIFT
index ac2d3fe..33e0f89 100755
Binary files a/ASIFT_tests/demo_ASIFT_src/test_ASIFT and b/ASIFT_tests/demo_ASIFT_src/test_ASIFT differ
diff --git a/ASIFT_tests/demo_ASIFT_src/test_ASIFT.cpp b/ASIFT_tests/demo_ASIFT_src/test_ASIFT.cpp
index 3d1d76d..ccb6688 100644
--- a/ASIFT_tests/demo_ASIFT_src/test_ASIFT.cpp
+++ b/ASIFT_tests/demo_ASIFT_src/test_ASIFT.cpp
@@ -2,13 +2,14 @@
 
 int main(int argc, char **argv)
 {			
-	if ((argc !=2) && (argc != 3) && (argc != 4)) {
+	if ((argc <2) || (argc > 5)) {
         std::cerr << " ******************************************************************************* " << std::endl
 				  << " ***************************  ASIFT image matching  **************************** " << std::endl
 				  << " ******************************************************************************* " << std::endl
-				  << "Usage: " << argv[0] << " imgIn.png [Tilt number option] [Resize option: 0/1] " << std::endl
+				  << "Usage: " << argv[0] << " imgIn.png [Tilt number option] [Filter option] [Resize option] " << std::endl
 									      << "- imgIn.png: input image (in PNG format). " << std::endl
-									      << "- [Tilt number option: 1..(32+ ?)] : 8: Recommended / 1: no tilt. " << std::endl 
+									      << "- [Tilt number option: 1..(32+ ?)] : 7: Recommended / 1: no tilt. " << std::endl
+									      << "- [Filter option: 0..3]. Standard deviation filter coeff (1-68%/2-95%/3-99%). 0: no filtering. " << std::endl 
 										  << "- [Resize option: 0/1]. 1: input images resize to 800x600 (default). 0: no resize. " << std::endl 
    				  << " ******************************************************************************* " << std::endl
 				  << " *********************  Jean-Michel Morel, Guoshen Yu, 2010 ******************** " << std::endl
@@ -36,12 +37,12 @@ int main(int argc, char **argv)
 	vector<float> ipixels1_zoom;	
 		
 	int flag_resize = 1;
-	if (argc == 4)
+	if (argc == 5)
 	{	
-		flag_resize = atoi(argv[3]);
+		flag_resize = atoi(argv[4]);
 	}
 	
-	if ((argc==2) || (argc == 3) || (flag_resize != 0))
+	if (flag_resize != 0)
 	{
 		cout << "WARNING: The input images is resized to " << wS << "x" << hS << " for ASIFT. " << endl 
 		<< "         But the results will be normalized to the original image size." << endl << endl;
@@ -101,24 +102,34 @@ int main(int argc, char **argv)
 		zoom1 = 1;
 	}
 
+
 	std::string refData[] = {
       "book_training/train_image_000.png", 
       "book_training/train_image_001.png"};
-	
+
     ASIFT_matcher matcher;
     matcher.setResizeImg(flag_resize);
 
     time_t tstart, tend;
 	tstart = time(0);
 
-    matcher.addReference(refData[0].c_str(), 8);
-    matcher.addReference(refData[1].c_str(), 8);
     // matcher.print();
     // matcher.match(refData[3].c_str(), 4);
     if(argc>2)
-    	matcher.match(ipixels1_zoom, wS1, hS1, atoi(argv[2]));
+    {
+		matcher.addReference(refData[0].c_str(), atoi(argv[2]));
+		matcher.addReference(refData[1].c_str(), atoi(argv[2]));
+		matcher.match(ipixels1_zoom, wS1, hS1, atoi(argv[2]));
+    }
 	else
+	{
+		matcher.addReference(refData[0].c_str(), 7);
+    	matcher.addReference(refData[1].c_str(), 7);
 		matcher.match(ipixels1_zoom, wS1, hS1);
+	}
+
+	if(argc>3 && atoi(argv[3])>0)
+		matcher.distFilter(atoi(argv[3]));
 
 	tend = time(0);
 
@@ -130,17 +141,13 @@ int main(int argc, char **argv)
     	cout<<"	"<<NbMatch[i]<<endl;
     }
 	
-	int x =0,y=0;
-	unsigned int h=1,w=1;
-	matcher.computeROI(x,y,h,w);
-	
+	int x,y,cx,cy;
+	unsigned int h,w;
 	
 	float *opixelsASIFT = new float[w1*h1];
 	/////////////////////////////////////////////////////////////////// Copy image to output
 	for(int j = 0; j < (int) h1; j++)
-		for(int i = 0; i < (int) w1; i++)  opixelsASIFT[j*w1+i] = ipixels1[j*w1+i];				
-	//////////////////////////////////////////////////////////////////// Draw ROI	
-	draw_square(opixelsASIFT, zoom1*x, zoom1*y, zoom1*w, zoom1*h, 255, w1, h1);
+		for(int i = 0; i < (int) w1; i++)  opixelsASIFT[j*w1+i] = ipixels1[j*w1+i];	
 
 	//////////////////////////////////////////////////////////////////// Draw matches
 	int point_size = 2;
@@ -152,6 +159,19 @@ int main(int argc, char **argv)
 			draw_square(opixelsASIFT, (int) (zoom1*ptrH->first.x), (int) (zoom1*ptrH->first.y), point_size, point_size, 255, w1, h1);
 		}
 	}
+
+	//////////////////////////////////////////////////////////////////// Draw ROI	
+	if(matcher.computeROI(x,y,h,w))
+		draw_square(opixelsASIFT, zoom1*x, zoom1*y, zoom1*w, zoom1*h, 255, w1, h1);
+	
+	//////////////////////////////////////////////////////////////////// Draw Center
+	if(matcher.computeCenter(cx,cy))
+	{
+		draw_square(opixelsASIFT, zoom1*(cx-6), zoom1*(cy-6), zoom1*12, zoom1*12, 160, w1, h1);
+		draw_line(opixelsASIFT, zoom1*cx, zoom1*(cy-6), zoom1*cx, zoom1*(cy+6), 255, w1, h1);
+		draw_line(opixelsASIFT, zoom1*(cx-6), zoom1*cy, zoom1*(cx+6), zoom1*cy, 255, w1, h1);
+	}
+
 	///////////////////////////////////////////////////////////////// Save imgOut	
 	write_png_f32("./results/res.png", opixelsASIFT, w1, h1, 1);