Color Detection System with Arduino & Python

1#include <LiquidCrystal.h>
2
3// RS, E, D4, D5, D6, D7
4LiquidCrystal lcd(12, 11, 5, 4, 3, 2);
5
6char colorCmd = 'N'; // 接收颜色命令
7
8void setup() {
9  lcd.begin(16, 2); // 16x2 LCD
10  lcd.print("Ready...");
11  Serial.begin(9600);
12}
13
14void loop() {
15  if (Serial.available()) {
16    colorCmd = Serial.read();
17    lcd.clear();
18    lcd.setCursor(0,0);
19    lcd.print("Detected Color:"); 
20    lcd.setCursor(0,1);
21
22    if (colorCmd == 'R') lcd.print("RED");
23    else if (colorCmd == 'G') lcd.print("GREEN");
24    else if (colorCmd == 'B') lcd.print("BLUE");
25    else lcd.print("NONE");
26  }
27}

1import cv2
2import numpy as np
3import serial
4import time
5
6# Arduino port, COM5 is the USB port of arduino (this can be changed based on the COM port of your computer)
7arduino = serial.Serial('COM5', 9600)
8time.sleep(2) 
9
10cap = cv2.VideoCapture(0)
11
12# HSV RGB range
13lower_red1 = np.array([0, 50, 50])
14upper_red1 = np.array([10, 255, 255])
15lower_red2 = np.array([160, 50, 50])
16upper_red2 = np.array([180, 255, 255])
17
18lower_green = np.array([35, 50, 50])
19upper_green = np.array([85, 255, 255])
20
21lower_blue = np.array([100, 50, 50])
22upper_blue = np.array([140, 255, 255])
23
24while True:
25    ret, frame = cap.read()
26    if not ret:
27        break
28
29    hsv = cv2.cvtColor(frame, cv2.COLOR_BGR2HSV)
30
31    # generate mask for every colour
32    mask_r = cv2.inRange(hsv, lower_red1, upper_red1) + cv2.inRange(hsv, lower_red2, upper_red2)
33    mask_g = cv2.inRange(hsv, lower_green, upper_green)
34    mask_b = cv2.inRange(hsv, lower_blue, upper_blue)
35
36    # find the percentage(pixel) of a colour in the camera
37    r_area = np.sum(mask_r > 0)
38    g_area = np.sum(mask_g > 0)
39    b_area = np.sum(mask_b > 0)
40
41    # find the colour that takes the most area
42    areas = {'R': r_area, 'G': g_area, 'B': b_area}
43    max_color = max(areas, key=areas.get)
44
45    # if area too small, set to none
46    if areas[max_color] < 50:
47        max_color = 'N'
48
49    # send to Arduino
50    arduino.write(max_color.encode())
51
52    # visualize it
53    cv2.putText(frame, f"Max Color: {max_color}", (10,30), cv2.FONT_HERSHEY_SIMPLEX,
54                1, (0,255,0), 2)
55    cv2.imshow("Camera Frame", frame)
56
57    if cv2.waitKey(1) & 0xFF == ord('q'):
58        break
59
60cap.release()
61cv2.destroyAllWindows()
62arduino.close()