diff --git a/ROS/gesture_based_control/src/controller.cpp b/ROS/gesture_based_control/src/controller.cpp
index 6223ccb..e6117f5 100644
--- a/ROS/gesture_based_control/src/controller.cpp
+++ b/ROS/gesture_based_control/src/controller.cpp
@@ -3,15 +3,15 @@
 #include <geometry_msgs/Twist.h>
 
 void callback(const std_msgs::String& msg, geometry_msgs::Twist& cmd) {
-  if (msg.data == "forward") {
+  if (msg.data == "avance") {
     cmd.linear.x = 1.0;
     cmd.angular.z = 0.0;
-  } else if (msg.data == "stop") {
+  } else if (msg.data == "arret") {
     cmd = geometry_msgs::Twist();
-  } else if (msg.data == "left") {
+  } else if (msg.data == "gauche") {
     cmd.angular.z = 1.0;
     cmd.linear.x = 0.0;
-  } else if (msg.data == "right") {
+  } else if (msg.data == "droite") {
     cmd.angular.z = -1.0;
     cmd.linear.x = 0.0;
   }
diff --git a/ROS/gesture_based_control/src/descripteur.cpp b/ROS/gesture_based_control/src/descripteur.cpp
index cb370ca..4c5500d 100644
--- a/ROS/gesture_based_control/src/descripteur.cpp
+++ b/ROS/gesture_based_control/src/descripteur.cpp
@@ -7,13 +7,14 @@
 
 #include <gesture_based_control/DescriptorsConfig.h>
 #include "math.hpp"
+#include "file.hpp"
+#include "knn.hpp"
 
 void callback(gesture_based_control::DescriptorsConfig &config, uint32_t level, int& cmax, int& threshold) {
-  cmax = config.cmax;
   threshold = config.threshold;
 }
 
-void callback(const sensor_msgs::ImageConstPtr& msg, int& threshold, int& cmax, ros::Publisher& order_pub, image_transport::Publisher& image_pub) {
+void callback(const sensor_msgs::ImageConstPtr& msg, int& threshold, int& cmax, ros::Publisher& order_pub, image_transport::Publisher& image_pub, math::dataset& dataset) {
   cv_bridge::CvImagePtr cv_ptr;
   std_msgs::String s;
 
@@ -35,26 +36,7 @@ void callback(const sensor_msgs::ImageConstPtr& msg, int& threshold, int& cmax,
   if (contours.size() != 0) {
     int index = math::max_cont(contours);
     math::csignal desc = math::descriptors(contours[index], cmax);
-    //TODO: implémenter algo ml
-    //TODO: publier résultat
-    int r = 0;
-    switch (r) {
-      case 0:
-        s.data = "left";
-        break;
-      case 1:
-        s.data = "right";
-        break;
-      case 2:
-        s.data = "stop";
-        break;
-      case 3:
-        s.data = "forward";
-        break;
-      default:
-        s.data = "None";
-        break;
-    }
+    s.data = predict(desc, dataset, 5, 2);
     order_pub.publish(s);
 
     cv::drawContours(input, contours, index, 255);
@@ -68,12 +50,14 @@ int main(int argc, char** argv) {
   int threshold = 25;
   int cmax = 10;
 
+  math::dataset dataset = load_csv("/home/guillaume/Documents/3A_supelec/miniprojet/learning/descripteurs/dataset50.csv", 21);
+
   ros::NodeHandle n;
   image_transport::ImageTransport it(n);
 
   ros::Publisher order_pub = n.advertise<std_msgs::String>("/order", 100);
   image_transport::Publisher image_pub = it.advertise("/image_out", 1);
-  image_transport::Subscriber sub = it.subscribe("/image_raw", 1, boost::bind(callback, _1, boost::ref(threshold), boost::ref(cmax), boost::ref(order_pub), boost::ref(image_pub)));
+  image_transport::Subscriber sub = it.subscribe("/image_raw", 1, boost::bind(callback, _1, boost::ref(threshold), boost::ref(cmax), boost::ref(order_pub), boost::ref(image_pub), boost::ref(dataset)));
 
   dynamic_reconfigure::Server<gesture_based_control::DescriptorsConfig> server;
   dynamic_reconfigure::Server<gesture_based_control::DescriptorsConfig>::CallbackType f;
diff --git a/tests/examples/test-knn.cpp b/tests/examples/test-knn.cpp
new file mode 100644
index 0000000..a2267b4
--- /dev/null
+++ b/tests/examples/test-knn.cpp
@@ -0,0 +1,33 @@
+#include <iostream>
+#include <math.hpp>
+#include <file.hpp>
+#include <knn.hpp>
+
+int main(int argc, char** argv) {
+  int k = 20;
+  std::string filename;
+  std::string sample_name;
+  int cmax = 10;
+  int threshold = 20;
+  int n = 2;
+
+  if (argc > 3) {
+    filename = argv[1];
+    k = atoi(argv[2]);
+    sample_name = argv[3];
+  } else {
+    std::cout << "Invalid number of arguments" << std::endl;
+    return 0;
+  }
+
+  math::dataset references = load_csv(filename, 2*cmax+1);
+
+  if (references.size() == 0) {
+    std::cout << "Invalid file" << std::endl;
+    return 0;
+  }
+
+  sample_name = random_image(sample_name);
+  math::csignal sample = math::img2desc(sample_name, cmax, threshold);
+  std::cout << predict(sample, references, k, n) << std::endl;
+};
diff --git a/tests/src/CMakeLists.txt b/tests/src/CMakeLists.txt
index a92c8b5..d63dcd4 100644
--- a/tests/src/CMakeLists.txt
+++ b/tests/src/CMakeLists.txt
@@ -1,8 +1,8 @@
 add_executable(traitement traitement.cpp)
 target_link_libraries(traitement ${OpenCV_LIBS})
 
-add_executable(knn knn.cpp)
-target_link_libraries(knn ${OpenCV_LIBS} ${Boost_SYSTEM_LIBRARY} ${Boost_FILESYSTEM_LIBRARY})
+add_executable(save-dataset save-dataset.cpp)
+target_link_libraries(save-dataset ${OpenCV_LIBS} ${Boost_SYSTEM_LIBRARY} ${Boost_FILESYSTEM_LIBRARY})
 
 add_executable(neural_network neural_network.cpp)
 target_link_libraries(neural_network ${OpenCV_LIBS} ${Boost_FILESYSTEM_LIBRARY} ${Boost_SYSTEM_LIBRARY})
diff --git a/tests/src/file.hpp b/tests/src/file.hpp
index 0dde7e6..74f823f 100644
--- a/tests/src/file.hpp
+++ b/tests/src/file.hpp
@@ -1,4 +1,7 @@
+#pragma once
+
 #include <boost/filesystem.hpp>
+#include <random>
 #include <iostream>
 #include <string>
 #include "math.hpp"
@@ -18,15 +21,9 @@ void read_directory(const std::string& name, std::vector<std::string>& v) {
 }
 
 void save_as_csv(const math::dataset& dataset, std::string filename) {
-	// file pointer
   std::fstream fout;
-
-	// opens an existing csv file or creates a new file.
 	fout.open(filename, std::ios::out);
 
-  std::string name;
-
-  // Insert the data to file
   for (auto p: dataset) {
     for (auto x: p.first) {
       fout << x.real() << ','
@@ -37,6 +34,24 @@ void save_as_csv(const math::dataset& dataset, std::string filename) {
   }
 }
 
+std::string random_image(const std::string& path) {
+  std::random_device rd;
+  std::mt19937 gen(rd());
+  std::uniform_int_distribution<> uniform(0, 4);
+
+
+  std::vector<std::string> dirs;
+  read_directory(path, dirs);
+  int rd_dir = uniform(gen);
+  std::vector<std::string> images;
+  read_directory(path+"/"+dirs[rd_dir], images);
+
+  std::uniform_int_distribution<> uniform2(0, images.size());
+  int rd_image = uniform2(gen);
+  std::cout << images[rd_image] << std::endl;
+  return path+"/"+dirs[rd_dir]+"/"+images[rd_image];
+}
+
 math::dataset& load_csv(std::string filename, int size) {
   math::dataset* d = new math::dataset();
   std::fstream fin; 
diff --git a/tests/src/knn.cpp b/tests/src/knn.hpp
similarity index 60%
rename from tests/src/knn.cpp
rename to tests/src/knn.hpp
index 60b420f..0cff472 100644
--- a/tests/src/knn.cpp
+++ b/tests/src/knn.hpp
@@ -1,17 +1,19 @@
-#include <map>
-#include "file.hpp"
-#include "math.hpp"
+#pragma once
+
 #include <stdexcept>
 #include <queue>
 #include <opencv2/opencv.hpp>
 #include <iostream>
+#include <map>
 
-double distance(math::csignal& v1, math::csignal& v2, int n){
+#include "file.hpp"
+#include "math.hpp"
+
+double distance(const math::csignal& v1, const math::csignal& v2, int n){
   if (v1.size() != v2.size()) {
     throw std::runtime_error("les deux vecteurs doivent être de même longueur");
   }
   double d = 0;
-
   auto v1_it = v1.begin();
   auto v2_it = v2.begin();
 
@@ -19,19 +21,7 @@ double distance(math::csignal& v1, math::csignal& v2, int n){
     double dist = std::abs(*(v1_it++) - *(v2_it++));
     d += std::pow(dist, n);
   }
-  return std::pow(d, 1/n);
-};
-
-int argmax(std::vector<int>& v){
-  int arg = 0;
-  int max = v[0];
-  for(int i = 1; i < v.size() ; ++i){
-    if (v[i]>max){
-      arg = i;
-      max = v[i];
-    };
-  };
-  return arg;
+  return std::pow(d, 1/float(n));
 };
 
 struct pair_comp {
@@ -46,29 +36,12 @@ struct pair_comp {
   };
 };
 
-
-int main(int argc, char** argv) {
-  int k = 20;
-  int size = 100;
-  std::string path;
-  int cmax = 10;
-  int threshold = 20;
-
-  if (argc > 2) {
-    path = argv[1];
-    threshold = atoi(argv[2]);
-  } else {
-    std::cout << "Invalid number of arguments" << std::endl;
-    return 0;
-  }
-
-  math::dataset references = get_data(path, size, cmax, threshold);
-  math::csignal sample = math::img2desc(path+"/arret/arret0199.jpg", cmax, threshold);
+std::string predict(const math::csignal& sample, const math::dataset& references, int k, int n) {
   std::priority_queue<std::pair<double, std::string>, std::vector<std::pair<double, std::string>>, pair_comp> neighbors;
   std::map<std::string, int> labels;
 
   for (auto desc: references) {
-    double d = distance(desc.first, sample, 1);
+    double d = distance(desc.first, sample, n);
     neighbors.push({d, desc.second});
   }
   
@@ -88,5 +61,5 @@ int main(int argc, char** argv) {
     } 
   }
 
-  std::cout << label << std::endl;
-};
+  return label;
+}
diff --git a/tests/src/save-dataset.cpp b/tests/src/save-dataset.cpp
new file mode 100644
index 0000000..0fe10de
--- /dev/null
+++ b/tests/src/save-dataset.cpp
@@ -0,0 +1,23 @@
+#include "file.hpp"
+#include "math.hpp"
+
+int main(int argc, char** argv) {
+  std::string path;
+  int cmax;
+  int threshold;
+  int size;
+
+  if (argc > 4) {
+    path      = argv[1];
+    cmax      = atoi(argv[2]);
+    threshold = atoi(argv[3]);
+    size      = atoi(argv[4]);
+  } else {
+    std::cout << "Invalid number of arguments" << std::endl;
+    return 0;
+  }
+  
+  math::dataset dataset = get_data(path, size, cmax, threshold);
+  save_as_csv(dataset, path+"/../descripteurs/dataset"+std::to_string(size)+".csv");
+  return 0;
+}