Object Detection with ESP32-CAM and OpenCV

Difficulty Level: Intermediate

In this tutorial, you will learn how to set up the ESP32-CAM module to perform object detection using OpenCV. This project combines the power of the ESP32 microcontroller with the image processing capabilities of OpenCV.

Components Required

• ESP32-CAM Module
• FTDI Programmer or USB-to-TTL Converter
• Jumper Wires
• Computer with OpenCV Installed
• Arduino IDE
• Optional: Breadboard

Setting Up the ESP32-CAM

1. Connect the ESP32-CAM to your FTDI programmer:

• GND to GND
• 5V to VCC
• U0 to RX
• U1 to TX
• GPIO 0 to GND (for programming mode)

2. Open the Arduino IDE and install the necessary board libraries for ESP32.

3. Load the following example code to set up the camera:

#include "esp_camera.h"

void setup() {
    Serial.begin(115200);
    camera_config_t config;
    config.ledc_channel = LEDC_CHANNEL;
    config.ledc_freq = 5000;
    config.ledc_timer = LEDC_TIMER;
    config.pin_d0 = 0; // Adjust as necessary for your board
    config.pin_d1 = 26; // Adjust as necessary
    config.pin_d2 = 27; // Adjust as necessary
    config.pin_d3 = 25; // Adjust as necessary
    config.pin_d4 = 33; // Adjust as necessary
    config.pin_d5 = 32; // Adjust as necessary
    config.pin_d6 = 35; // Adjust as necessary
    config.pin_d7 = 34; // Adjust as necessary
    config.pin_xclk = 0; // Adjust as necessary
    config.pin_pclk = 22; // Adjust as necessary
    config.pin_vsync = 25; // Adjust as necessary
    config.pin_href = 23; // Adjust as necessary
    config.pin_sscb_sda = 26; // Adjust as necessary
    config.pin_sscb_scl = 27; // Adjust as necessary
    config.pin_pwdn = 32; // Adjust as necessary
    config.pin_reset = -1; // Reset pin
    config.xclk_freq_hz = 20000000;
    config.pixel_format = PIXFORMAT_JPEG;
    
    // Initialize the camera
    esp_err_t err = esp_camera_init(&config);
}

void loop() {
    // Your code to capture images and send them to OpenCV
}
        

Object Detection with OpenCV

1. Make sure you have OpenCV installed on your computer. You can install it via pip:

pip install opencv-python
        

2. Use the following Python script to capture video from the ESP32-CAM and perform object detection:

import cv2
import numpy as np

url = 'http:///stream' # Replace  with your ESP32-CAM IP

cap = cv2.VideoCapture(url)

while True:
    ret, frame = cap.read()
    if not ret:
        break
    
    # Perform object detection (e.g., using Haar cascades)
    # haar_cascade = cv2.CascadeClassifier('path/to/haarcascade.xml')
    # objects = haar_cascade.detectMultiScale(frame, scaleFactor=1.1, minNeighbors=5)
    
    # Display the results
    cv2.imshow('Object Detection', frame)

    if cv2.waitKey(1) & 0xFF == ord('q'):
        break

cap.release()
cv2.destroyAllWindows()
        

Explanation of Code

In this section, we explain the code:

• Camera Configuration: The ESP32-CAM is configured to use specific GPIO pins for the camera functions.
• Video Stream: The Python script captures video from the ESP32-CAM using its IP address.
• Object Detection: You can implement object detection using Haar cascades or other methods in OpenCV.

Conclusion

By following this tutorial, you have learned how to set up an ESP32-CAM for object detection using OpenCV. This integration allows you to create powerful IoT applications that utilize computer vision capabilities.

Additional Resources

• ESP32-CAM Video Streaming Web Server
• OpenCV Documentation