diff --git a/mes_gui.py b/mes_gui.py
index 27fd2c2..2796db0 100644
--- a/mes_gui.py
+++ b/mes_gui.py
@@ -1,14 +1,15 @@
-
-from gdx import gdx
 import threading
 import time
-import csv
 from abc import abstractmethod
+
+import cv2
 import numpy as np
 
+from gdx import gdx
+
 
 class DataWorker(threading.Thread):
-    def __init__(self, out_filename=""):
+    def __init__(self):
         threading.Thread.__init__(self)
         self._running = False
         self._start_time = 0
@@ -28,13 +29,13 @@
     def run(self):
         self.preprocess()
         self._running = True
-        self._data = np.array([tuple([0] * self._cols)])
+        self._data = np.array([tuple([0] * (self._num_channels + 1))])
         self._start_time = time.perf_counter()
         while self._running:
             measurements = self.read()
             current_time = time.perf_counter() - self._start_time
             measurements.insert(0, current_time)
-            if len(measurements) == self._cols:
+            if len(measurements) == self._num_channels + 1:
                 self._data = np.vstack([self._data, measurements])
             # print(measurements)
 
@@ -44,14 +45,15 @@
         self.postprocess()
         self._data = self._data[1:, :]
 
+
 class GoDirectWorker(DataWorker):
-    def __init__(self, out_filename):
-        super().__init__(out_filename)
+    def __init__(self):
+        super().__init__()
         # Connect GoDirect device
         self._gdx = gdx.gdx()
         self._gdx.open(connection="usb")
         self._gdx.select_sensors([1])
-        self._cols = 2
+        self._num_channels = 1
         print("GoDirect connected.")
 
     def preprocess(self):
@@ -64,19 +66,26 @@
         self._gdx.stop()
         self._gdx.close()
 
+
 if __name__ == "__main__":
-    godirect_worker = GoDirectWorker("")
+    win_name = "measurement"
+    cv2.namedWindow(win_name, cv2.WINDOW_NORMAL)
+    display_width = 800
+    display_height = 600
+
+    godirect_worker = GoDirectWorker()
     godirect_worker.start()
 
     # Wait for stop
     print("measurement start.")
-    recode_dulation = 3  # sec
-    for i in range(recode_dulation):
-        time.sleep(1)
-        print(i + 1, "/", recode_dulation, "sec")
+    while True:
+        disp = np.zeros((display_height, display_width, 3), np.uint8)
+        cv2.imshow(win_name, disp)
+        if cv2.waitKey(30) == 27:
+            break
+
     # input("Press ENTER to stop")
     print("measurement end.")
-    print(godirect_worker._data)
 
     # Closing
     godirect_worker.stop()