diff --git a/CMakeLists.txt b/CMakeLists.txt
index e82c318..a498a98 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -52,8 +52,8 @@ message("SRC_LIST is " ${SRC_LIST})
 SET(DEP_LIBS ${DEP_LIBS} ${PCL_LIBRARIES} ${OpenCV_LIBS} /usr/local/lib/libproj.so glog::glog ${GFLAGS_LIBRARIES})
 
 # Pure Lidar Odometry test
-add_executable(lo_test_kitti ${PROJECT_SOURCE_DIR}/samples/lidar_odometry_test_kitti.cpp ${SRC_LIST})
+add_executable(lo_test_kitti ${PROJECT_SOURCE_DIR}/test/lidar_odometry_test_kitti.cpp ${SRC_LIST})
 target_link_libraries(lo_test_kitti ${DEP_LIBS})
 
-add_executable(lo_test_apollo ${PROJECT_SOURCE_DIR}/samples/lidar_odometry_test_apollo.cpp ${SRC_LIST})
+add_executable(lo_test_apollo ${PROJECT_SOURCE_DIR}/test/lidar_odometry_test_apollo.cpp ${SRC_LIST})
 target_link_libraries(lo_test_apollo ${DEP_LIBS})
\ No newline at end of file
diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..b9919b0
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2019 Yue Pan
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
\ No newline at end of file
diff --git a/README.md b/README.md
index 11fabd6..909cfc2 100644
--- a/README.md
+++ b/README.md
@@ -2,15 +2,16 @@
 Lidar Odometry and Mapping with Mutiple Metrics Linear Least Square ICP
 
 ## Principle
-Instead of using non-linear optimization when doing transformation estimation, this algorithm use the linear least square for all of the point-to-point, point-to-line and point-to-plane distance metrics during the ICP registration process. 
+Instead of using non-linear optimization when doing transformation estimation, this algorithm use the linear least square for all of the point-to-point, point-to-line and point-to-plane distance metrics during the ICP registration process based on a good enough initial guess. 
 
 
 ## How to use
 
 1. Install dependent 3rd libraries: 
-PCL, OpenCV, Eigen, VTK, Glog, Gflags.
 
- If you'd like to use your own data and want to know its absolute projected coordinate, install Proj.
+[PCL](https://github.com/PointCloudLibrary/pcl), [OpenCV](https://github.com/opencv/opencv), [Eigen](https://eigen.tuxfamily.org/dox/), [Glog](https://github.com/google/glog), [Gflags](https://github.com/gflags/gflags).
+
+If you'd like to use your own data and want to know its absolute projected coordinate, install [Proj](https://proj.org/download.html).
 
 2. Compile
 ```
diff --git a/test/lidar_odometry_test_apollo.cpp b/test/lidar_odometry_test_apollo.cpp
new file mode 100644
index 0000000..761872e
--- /dev/null
+++ b/test/lidar_odometry_test_apollo.cpp
@@ -0,0 +1,56 @@
+#include <iostream>
+#include <fstream>
+#include <string>
+#include <map>
+
+#include <gflags/gflags.h>
+#include <glog/logging.h>
+
+#include <Eigen/Core>
+#include <Eigen/Geometry>
+
+#include "types.h"
+#include "llslo.h"
+#include "map_viewer.hpp"
+#include "dataio.hpp"
+
+DEFINE_int32(transaction_id, -1, "transaction id.");
+DEFINE_string(transaction_folder, "", "transaction folder.");
+DEFINE_string(pcd_filelist, "", "pcd file list.");
+DEFINE_string(config_file, "", "config file.");
+DEFINE_string(output_foler, "", "output folder.");
+DEFINE_int32(begin_frame_id, -1, "begin frame id.");
+DEFINE_int32(end_frame_id, -1, "end frame id.");
+DEFINE_string(exp_num, "1", "id of experiment");
+
+
+int main(int argc, char **argv)
+{
+    //google::SetLogDestination(google::GLOG_INFO, "./log");
+    google::ParseCommandLineFlags(&argc, &argv, true);
+    google::InitGoogleLogging("lls_loam"); // init google logging must be carried out after parse command line flags is carried out.
+    LOG(INFO) << "Logging is written to " << FLAGS_log_dir;
+    CHECK(FLAGS_transaction_folder != "") << "Need to specify the pcd folder to read.";
+    CHECK(FLAGS_pcd_filelist != "") << "Need to specify the pcd file list to read.";
+    CHECK(FLAGS_begin_frame_id != -1) << "Need to specify the begin frame id.";
+    CHECK(FLAGS_end_frame_id != -1) << "Need to specify the end frame id.";
+
+    lls_loam::transaction_param_t trsct_prm;
+    trsct_prm.transaction_id = FLAGS_transaction_id;
+    trsct_prm.transaction_root_path = FLAGS_transaction_folder;
+    trsct_prm.lidar_root_path = FLAGS_transaction_folder + "/HDL64";
+    trsct_prm.gnss_root_path = FLAGS_transaction_folder + "/OXTS";
+    trsct_prm.lidar_file_list = FLAGS_pcd_filelist;
+    trsct_prm.submap_full_root_path = FLAGS_transaction_folder + "/SubmapFull_" + FLAGS_exp_num;
+    trsct_prm.submap_feature_root_path = FLAGS_transaction_folder + "/SubmapFeature_" + FLAGS_exp_num;
+    //Key parameter to set
+    trsct_prm.local_map_max_size=10; //Local map's max frame number 
+
+    lls_loam::Transaction transaction(trsct_prm);
+
+    // Import Data
+    transaction.LoadApolloData(FLAGS_begin_frame_id,FLAGS_end_frame_id);
+
+    // Lidar Odometery
+    transaction.RunPureLidarOdometry(transaction.sub_maps_[0]);
+}
\ No newline at end of file
diff --git a/test/lidar_odometry_test_kitti.cpp b/test/lidar_odometry_test_kitti.cpp
new file mode 100644
index 0000000..edcf72c
--- /dev/null
+++ b/test/lidar_odometry_test_kitti.cpp
@@ -0,0 +1,56 @@
+#include <iostream>
+#include <fstream>
+#include <string>
+#include <map>
+
+#include <gflags/gflags.h>
+#include <glog/logging.h>
+
+#include <Eigen/Core>
+#include <Eigen/Geometry>
+
+#include "types.h"
+#include "llslo.h"
+#include "map_viewer.hpp"
+#include "dataio.hpp"
+
+DEFINE_int32(transaction_id, -1, "transaction id.");
+DEFINE_string(transaction_folder, "", "transaction folder.");
+DEFINE_string(pcd_filelist, "", "pcd file list.");
+DEFINE_string(config_file, "", "config file.");
+DEFINE_string(output_foler, "", "output folder.");
+DEFINE_int32(begin_frame_id, -1, "begin frame id.");
+DEFINE_int32(end_frame_id, -1, "end frame id.");
+DEFINE_string(exp_num, "1", "id of experiment");
+
+
+int main(int argc, char **argv)
+{
+    //google::SetLogDestination(google::GLOG_INFO, "./log");
+    google::ParseCommandLineFlags(&argc, &argv, true);
+    google::InitGoogleLogging("lls_loam"); // init google logging must be carried out after parse command line flags is carried out.
+    LOG(INFO) << "Logging is written to " << FLAGS_log_dir;
+    CHECK(FLAGS_transaction_folder != "") << "Need to specify the pcd folder to read.";
+    CHECK(FLAGS_pcd_filelist != "") << "Need to specify the pcd file list to read.";
+    CHECK(FLAGS_begin_frame_id != -1) << "Need to specify the begin frame id.";
+    CHECK(FLAGS_end_frame_id != -1) << "Need to specify the end frame id.";
+
+    lls_loam::transaction_param_t trsct_prm;
+    trsct_prm.transaction_id = FLAGS_transaction_id;
+    trsct_prm.transaction_root_path = FLAGS_transaction_folder;
+    trsct_prm.lidar_root_path = FLAGS_transaction_folder + "/HDL64";
+    trsct_prm.gnss_root_path = FLAGS_transaction_folder + "/OXTS";
+    trsct_prm.lidar_file_list = FLAGS_pcd_filelist;
+    trsct_prm.submap_full_root_path = FLAGS_transaction_folder + "/SubmapFull_" + FLAGS_exp_num;
+    trsct_prm.submap_feature_root_path = FLAGS_transaction_folder + "/SubmapFeature_" + FLAGS_exp_num;
+    //Key parameter to set
+    trsct_prm.local_map_max_size=10; //Local map's max frame number 
+
+    lls_loam::Transaction transaction(trsct_prm);
+
+    // Import Data
+    transaction.LoadKITTIData(FLAGS_begin_frame_id,FLAGS_end_frame_id);
+
+    // Lidar Odometery
+    transaction.RunPureLidarOdometry(transaction.sub_maps_[0]);
+}
\ No newline at end of file