diff --git a/distinction_color.py b/distinction_color.py
new file mode 100644
index 0000000..499ce2e
--- /dev/null
+++ b/distinction_color.py
@@ -0,0 +1,87 @@
+import threading
+
+import cv2
+import numpy as np
+
+current_img = None
+lock = threading.Lock()
+
+
+def detect_card_color(image_path):
+    img = cv2.imread(image_path)
+    if img is None:
+        raise FileNotFoundError(f"Cannot open image: {image_path}")
+
+    height, width = img.shape[:2]
+
+    crop_left = int(width * 0.33)
+    crop_right = int(width * 0.33)
+    center_w = width - crop_left - crop_right
+
+    center_img = img[:, crop_left:crop_left + center_w]
+
+    hsv = cv2.cvtColor(center_img, cv2.COLOR_BGR2HSV)
+
+    lower_red1 = np.array([0, 70, 50])
+    upper_red1 = np.array([10, 255, 255])
+    lower_red2 = np.array([170, 70, 50])
+    upper_red2 = np.array([180, 255, 255])
+
+    lower_green = np.array([35, 70, 50])
+    upper_green = np.array([85, 255, 255])
+
+    mask_red = cv2.inRange(hsv, lower_red1, upper_red1) | cv2.inRange(hsv, lower_red2, upper_red2)
+    mask_green = cv2.inRange(hsv, lower_green, upper_green)
+
+    def find_largest_contour(mask):
+        contours, _ = cv2.findContours(mask, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
+        if not contours:
+            return None, 0
+        largest = max(contours, key=cv2.contourArea)
+        return largest, cv2.contourArea(largest)
+
+    largest_red, area_red = find_largest_contour(mask_red)
+    largest_green, area_green = find_largest_contour(mask_green)
+
+    min_area = 5000
+
+    if area_red > area_green and area_red > min_area:
+        card_color = "red"
+        largest_contour = largest_red
+    elif area_green > area_red and area_green > min_area:
+        card_color = "green"
+        largest_contour = largest_green
+    else:
+        return None, None, img
+
+    x, y, w, h = cv2.boundingRect(largest_contour)
+    x_full = x + crop_left
+
+    return card_color, (x_full, y, w, h), img
+
+
+def process_and_show(card_color, rect, img):
+    global current_img
+    try:
+        if (card_color is not None) and (rect is not None):
+            x, y, w, h = rect
+            color_bgr = (0, 0, 255) if card_color == "red" else (0, 255, 0)
+            cv2.rectangle(img, (x, y), (x + w, y + h), color_bgr, 3)
+            cv2.putText(img, card_color, (x, y - 10), cv2.FONT_HERSHEY_SIMPLEX, 1, color_bgr, 2)
+
+        with lock:
+            current_img = img.copy()
+
+    except Exception as e:
+        print("Error in process_and_show:", e)
+
+
+def show_loop():
+    global current_img
+    while True:
+        with lock:
+            if current_img is not None:
+                cv2.imshow("Detected Card", current_img)
+        if cv2.waitKey(30) & 0xFF == 27:
+            break
+    cv2.destroyAllWindows()
diff --git a/server.py b/server.py
new file mode 100644
index 0000000..373087b
--- /dev/null
+++ b/server.py
@@ -0,0 +1,51 @@
+from flask import Flask, request, url_for
+import os
+import distinction_color
+import threading
+
+app = Flask(__name__)
+
+UPLOAD_FOLDER = 'uploads'
+os.makedirs(UPLOAD_FOLDER, exist_ok=True)
+
+
+@app.route('/upload', methods=['POST'])
+def upload_image():
+    img_data = request.data
+
+    if not img_data:
+        return "No data has been received.", 400
+
+    file_path = os.path.join(UPLOAD_FOLDER, 'esp32_image.jpg')
+
+    with open(file_path, 'wb') as f:
+        f.write(img_data)
+    try:
+        infor_img = distinction_color.detect_card_color(file_path)
+        threed = threading.Thread(target=distinction_color.process_and_show,
+                                  args=(infor_img[0], infor_img[1], infor_img[2]), daemon=True)
+        threed.start()
+        if infor_img[0] is None:
+            return 'No expected color found.', 422
+        else:
+            return infor_img[0], 200
+
+
+    except Exception as e:
+        return e, 500
+
+
+if __name__ == '__main__':
+    try:
+        host = input('Server host: (Default: localhost) ')
+        host = '0.0.0.0' if host == '' else host
+        port = input('Server port: (Default: 8080) ')
+        port = 8080 if not bool(port) else int(port)
+    except ValueError:
+        host = 'localhost'
+        port = 8080
+    try:
+        threading.Thread(target=distinction_color.show_loop, daemon=True).start()
+        app.run(host=host, port=port)
+    except KeyboardInterrupt:
+        print('Server stopped by user.')