ESP32-CAM Color Object Detector Demo

// ESP32-CAM color object presence demo
// This is image processing, not machine-learning object detection.
#include "esp_camera.h"

#define PWDN_GPIO 32
#define RESET_GPIO -1
#define XCLK_GPIO 0
#define SIOD_GPIO 26
#define SIOC_GPIO 27
#define Y9_GPIO 35
#define Y8_GPIO 34
#define Y7_GPIO 39
#define Y6_GPIO 36
#define Y5_GPIO 21
#define Y4_GPIO 19
#define Y3_GPIO 18
#define Y2_GPIO 5
#define VSYNC_GPIO 25
#define HREF_GPIO 23
#define PCLK_GPIO 22

const int LED_PIN = 33;
const float DETECT_THRESHOLD = 0.05;

bool setupCamera() {
  camera_config_t config;
  config.ledc_channel = LEDC_CHANNEL_0;
  config.ledc_timer = LEDC_TIMER_0;
  config.pin_d0 = Y2_GPIO; config.pin_d1 = Y3_GPIO; config.pin_d2 = Y4_GPIO; config.pin_d3 = Y5_GPIO;
  config.pin_d4 = Y6_GPIO; config.pin_d5 = Y7_GPIO; config.pin_d6 = Y8_GPIO; config.pin_d7 = Y9_GPIO;
  config.pin_xclk = XCLK_GPIO; config.pin_pclk = PCLK_GPIO; config.pin_vsync = VSYNC_GPIO; config.pin_href = HREF_GPIO;
  config.pin_sscb_sda = SIOD_GPIO; config.pin_sscb_scl = SIOC_GPIO;
  config.pin_pwdn = PWDN_GPIO; config.pin_reset = RESET_GPIO;
  config.xclk_freq_hz = 20000000;
  config.pixel_format = PIXFORMAT_RGB565;
  config.frame_size = FRAMESIZE_QQVGA;
  config.jpeg_quality = 12;
  config.fb_count = 1;
  return esp_camera_init(&config) == ESP_OK;
}

float orangeFraction(camera_fb_t *fb) {
  uint16_t *pixels = (uint16_t *)fb->buf;
  size_t total = fb->width * fb->height;
  size_t matches = 0;
  for (size_t i = 0; i < total; i++) {
    uint16_t px = pixels[i];
    int r = (px >> 11) & 0x1F;
    int g = (px >> 5) & 0x3F;
    int b = px & 0x1F;
    if (r > 18 && g > 18 && g < 50 && b < 14) matches++;
  }
  return (float)matches / (float)total;
}

void setup() {
  Serial.begin(115200);
  pinMode(LED_PIN, OUTPUT);
  if (!setupCamera()) {
    Serial.println("Camera init failed");
    while (true) delay(1000);
  }
  Serial.println("Color object presence demo ready.");
}

void loop() {
  camera_fb_t *fb = esp_camera_fb_get();
  if (!fb) {
    Serial.println("Capture failed");
    delay(1000);
    return;
  }
  float fraction = orangeFraction(fb);
  esp_camera_fb_return(fb);
  bool detected = fraction > DETECT_THRESHOLD;
  digitalWrite(LED_PIN, detected ? LOW : HIGH); // AI-Thinker flash LED is often active LOW
  Serial.printf("orange_fraction=%.3f detected=%s\n", fraction, detected ? "YES" : "no");
  delay(1000);
}