diff --git a/.gitignore b/.gitignore
index 1c20eca..14ecd7d 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,3 @@
 *.mp4
 *.csv
+*.png
diff --git a/__pycache__/lumen_profiler.cpython-313.pyc b/__pycache__/lumen_profiler.cpython-313.pyc
new file mode 100644
index 0000000..b550c01
--- /dev/null
+++ b/__pycache__/lumen_profiler.cpython-313.pyc
Binary files differ
diff --git a/gui_app.py b/gui_app.py
index d3fd882..2bc4cd2 100644
--- a/gui_app.py
+++ b/gui_app.py
@@ -1,9 +1,63 @@
-from tkinter import *
+import tkinter as tk
+import tkinter.filedialog
 
-master = Tk()
-w = Scale(master, from_=0, to=42)
-w.pack()
-w = Scale(master, from_=0, to=200, orient=HORIZONTAL)
-w.pack()
+from PIL import Image, ImageOps, ImageTk
 
-mainloop()
+import lumen_profiler
+
+
+class GuiApp:
+    def __init__(self):
+        self.tkroot = tk.Tk()
+        self.lp = lumen_profiler.LumenProfiler()
+
+    def make_window(self):
+        self.tkroot.title("Lumen Profiler")
+        self.tkroot.geometry("800x600")
+        self.top_frame = tk.Frame(self.tkroot)
+        self.top_frame.pack(fill=tk.X)
+        self.file_button = tk.Button(
+            self.top_frame, text="映像ファイルを開く", command=self.open_movie
+        )
+        self.file_button.pack(side=tk.LEFT)
+        self.file_text = tk.Label(self.top_frame, text="no movie")
+        self.file_text.pack(side=tk.LEFT, fill=tk.X)
+        self.canvas = tk.Canvas(self.tkroot)
+        self.canvas.pack(fill=tk.BOTH, expand=True)
+        self.time_slider = tk.Scale(
+            self.tkroot,
+            from_=0,
+            to=0,
+            orient=tk.HORIZONTAL,
+            command=self.on_time_slider_change,
+        )
+        self.time_slider.pack(fill=tk.X)
+
+        self.tkroot.mainloop()
+
+    def open_movie(self):
+        filename = tk.filedialog.askopenfilename(filetypes=[("mp4", "*.mp4")])
+        if filename == "":  # cancel
+            return
+        self.lp.load_movie(filename)
+        self.file_text.config(text=filename)
+        self.time_slider.set(0)
+        self.time_slider.config(to=self.lp.frame_count - 1)
+        self.show_image(self.lp.frames[0])
+
+    def on_time_slider_change(self, event):
+        rid = self.time_slider.get()
+        self.show_image(self.lp.frames[rid])
+
+    def show_image(self, img):
+        pil = Image.fromarray(self.lp.bgr2rgb(img))
+        pil = ImageOps.pad(pil, (self.canvas.winfo_width(), self.canvas.winfo_height()))
+        self.disp = ImageTk.PhotoImage(pil)
+        # self.canvas.delete("all")
+        self.canvas.create_image(0, 0, image=self.disp, anchor=tk.NW)
+
+
+# main
+if __name__ == "__main__":
+    app = GuiApp()
+    app.make_window()
diff --git a/lumen_profiler.py b/lumen_profiler.py
index 52d6e35..2e6bfb5 100644
--- a/lumen_profiler.py
+++ b/lumen_profiler.py
@@ -5,7 +5,7 @@
 import numpy as np
 
 
-class lumen_profiler:
+class LumenProfiler:
     def __init__(self):
         self.area_ratio = 0.08
 
@@ -142,6 +142,11 @@
                 ]
                 writer.writerow(row_data)
 
+    def bgr2rgb(self, img, size=None):
+        if size is not None:
+            img = cv2.resize(img, size)
+        return cv2.cvtColor(img, cv2.COLOR_BGR2RGB)
+
 
 # def func():
 #             cv2.putText(
@@ -162,7 +167,7 @@
         movie_file = args[1]
 
     # 解析
-    lp = lumen_profiler()
+    lp = LumenProfiler()
     lp.load_movie(movie_file)
     lp.profiling(2)
     lp.csv_output("output/analysis.csv")
diff --git a/test.py b/test.py
new file mode 100644
index 0000000..149b9e4
--- /dev/null
+++ b/test.py
@@ -0,0 +1,21 @@
+import tkinter as tk
+
+import cv2
+from PIL import Image, ImageOps, ImageTk
+
+
+def show_image():
+    global disp
+    img = cv2.imread("img.png")
+    pil = Image.fromarray(cv2.cvtColor(img, cv2.COLOR_BGR2RGB))
+    pil = ImageOps.pad(pil, (canvas.winfo_width(), canvas.winfo_height()))
+    disp = ImageTk.PhotoImage(pil)
+    canvas.create_image(0, 0, image=disp, anchor=tk.NW)  # dispの生存期間に注意
+
+
+tkroot = tk.Tk()
+button = tk.Button(tkroot, text="画像を表示", command=show_image)
+button.pack()
+canvas = tk.Canvas(tkroot)
+canvas.pack(fill=tk.BOTH, expand=True)
+tkroot.mainloop()