ESP32-CAM实操：烧录固件、拍照上传与局域网图传

ESP32-CAM 这块板子，把 ESP32-S 主控、OV2640 摄像头和 microSD 卡槽全塞在 27×40mm 里，官网定价不到 10 美元，国内渠道十几块人民币就能拿到。便宜是真便宜，但它没有 USB 口，烧录要自己搭串口环境，劝退过不少新手。这篇把整条链路一次理顺：认清引脚、接 FTDI 烧录、跑通拍照上传和局域网网页图传。查证过安信可官方规格和几篇社区教程后，把容易踩的坑都标了出来。

AI-Thinker ESP32-CAM 开发板实物

一、先认清引脚：GPIO0 决定你是烧录还是运行

板子两侧是双排 2.54mm 排针，官方引脚定义里电源有三组 GND，供电选 5V 或 3.3V 引脚，官方规格标称工作电压 5V、逻辑电平 3.3V。串口引脚是 U0R 和 U0T（对应 GPIO3 和 GPIO1），烧录程序走这两个脚。

最关键的一根是 GPIO0：接地进烧录模式，悬空或拉高才是正常运行。很多人第一次烧不进去，十有八九是这根线没接或者烧完忘了拔。另外 GPIO4 同时接了板载白色闪光灯，SD 卡占了 GPIO2、4、12、13、14、15，做别的用途前先查一下引脚占用表，别跟卡槽打架。

ESP32-CAM 引脚定义图

二、烧录接线：一根杜邦线立大功

烧录要外接 USB 转 TTL 模块，CH340、CP2102、FTDI 都可以。接线按下面的交叉规则来：

USB 转 TTL 模块	ESP32-CAM
5V	5V
GND	GND
TX	U0R
RX	U0T
GPIO0	GND（仅烧录时接）

两个高频坑提前说：第一，串口是交叉接的，TX 接 U0R、RX 接 U0T，接反了就是连不上；第二，别用模块的 3.3V 输出给板子供电，摄像头加 Wi-Fi 峰值电流能到 300mA 以上，3.3V 输出带不动，轻则上传失败重则芯片反复重启。用 5V 引脚供电，最好是独立电源，别只靠电脑 USB 口。

FTDI 编程器与 ESP32-CAM 接线

三、Arduino IDE 环境与烧录步骤

环境搭建三步：Arduino IDE 首选项里的附加开发板管理器网址填 https://dl.espressif.com/dl/package_esp32_index.json，开发板管理器里搜 esp32 装乐鑫官方包，然后工具菜单里开发板选 AI Thinker ESP32-CAM、上传速度 115200。CH340 驱动提前装好，设备管理器里能看到 COM 口再动手。

第一次点亮建议直接跑库自带的 CameraWebServer 例程：文件菜单打开"示例 → ESP32 → Camera → CameraWebServer"，只需改两处。第一处填自家 Wi-Fi 的账号密码：

const char* ssid = "REPLACE_WITH_YOUR_SSID";
const char* password = "REPLACE_WITH_YOUR_PASSWORD";

第二处选对摄像头型号，只保留 AI-Thinker 这一行不被注释：

#define CAMERA_MODEL_AI_THINKER

然后点上传。上传开始后如果进度条卡住不动，按一下板子背面的 RST 键让它进烧录模式，几十秒后提示上传完成。烧完第一件事：断开 GPIO0 与 GND 的连接，再按一次 RST，程序才正常运行。

四、拍照上传与局域网图传

烧录成功后打开串口监视器，波特率 115200，按 RST 复位，几秒内会打印出类似 Camera Ready! Use 'http://192.168.1.123' to connect 的信息，这就是板子从路由器拿到的局域网地址。手机或电脑连同一个 Wi-Fi，浏览器打开这个 IP 就能看到控制页：点 Get Still 拍一张静态照片并上传显示，点 Start Stream 开始 MJPEG 实时视频流。分辨率、画质、翻转这些参数都能在页面上直接调，不用重烧程序。

ESP32-CAM 网页视频流画面

如果想把整条链路的代码吃透，官方例程基础上还有一份更精简的独立流服务版本，只用 esp_camera 库起两个 HTTP 端点：80 端口出静态页，81 端口出 MJPEG 流。社区里 Rui Santos 的版本最完整，代码原样贴在下面，Wi-Fi 信息换成自己的就能烧：

/*********
  Rui Santos
  Complete project details at https://RandomNerdTutorials.com/esp32-cam-video-streaming-web-server-camera-home-assistant/
  
  IMPORTANT!!! 
   - Select Board "AI Thinker ESP32-CAM"
   - GPIO 0 must be connected to GND to upload a sketch
   - After connecting GPIO 0 to GND, press the ESP32-CAM on-board RESET button to put your board in flashing mode
  
  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files.

  The above copyright notice and this permission notice shall be included in all
  copies or substantial portions of the Software.
*********/

#include "esp_camera.h"
#include "WiFi.h"
#include "esp_timer.h"
#include "img_converters.h"
#include "Arduino.h"
#include "fb_gfx.h"
#include "soc/soc.h" //disable brownout problems
#include "soc/rtc_cntl_reg.h"  //disable brownout problems
#include "esp_http_server.h"

//Replace with your network credentials
const char* ssid = "REPLACE_WITH_YOUR_SSID";
const char* password = "REPLACE_WITH_YOUR_PASSWORD";

#define PART_BOUNDARY "123456789000000000000987654321"

// This project was tested with the AI Thinker Model, M5STACK PSRAM Model and M5STACK WITHOUT PSRAM
#define CAMERA_MODEL_AI_THINKER
//#define CAMERA_MODEL_M5STACK_PSRAM
//#define CAMERA_MODEL_M5STACK_WITHOUT_PSRAM

// Not tested with this model
//#define CAMERA_MODEL_WROVER_KIT

#if defined(CAMERA_MODEL_WROVER_KIT)
  #define PWDN_GPIO_NUM    -1
  #define RESET_GPIO_NUM   -1
  #define XCLK_GPIO_NUM    21
  #define SIOD_GPIO_NUM    26
  #define SIOC_GPIO_NUM    27
  
  #define Y9_GPIO_NUM      35
  #define Y8_GPIO_NUM      34
  #define Y7_GPIO_NUM      39
  #define Y6_GPIO_NUM      36
  #define Y5_GPIO_NUM      19
  #define Y4_GPIO_NUM      18
  #define Y3_GPIO_NUM       5
  #define Y2_GPIO_NUM       4
  #define VSYNC_GPIO_NUM   25
  #define HREF_GPIO_NUM    23
  #define PCLK_GPIO_NUM    22

#elif defined(CAMERA_MODEL_M5STACK_PSRAM)
  #define PWDN_GPIO_NUM     -1
  #define RESET_GPIO_NUM    15
  #define XCLK_GPIO_NUM     27
  #define SIOD_GPIO_NUM     25
  #define SIOC_GPIO_NUM     23
  
  #define Y9_GPIO_NUM       19
  #define Y8_GPIO_NUM       36
  #define Y7_GPIO_NUM       18
  #define Y6_GPIO_NUM       39
  #define Y5_GPIO_NUM        5
  #define Y4_GPIO_NUM       34
  #define Y3_GPIO_NUM       35
  #define Y2_GPIO_NUM       32
  #define VSYNC_GPIO_NUM    22
  #define HREF_GPIO_NUM     26
  #define PCLK_GPIO_NUM     21

#elif defined(CAMERA_MODEL_M5STACK_WITHOUT_PSRAM)
  #define PWDN_GPIO_NUM     -1
  #define RESET_GPIO_NUM    15
  #define XCLK_GPIO_NUM     27
  #define SIOD_GPIO_NUM     25
  #define SIOC_GPIO_NUM     23
  
  #define Y9_GPIO_NUM       19
  #define Y8_GPIO_NUM       36
  #define Y7_GPIO_NUM       18
  #define Y6_GPIO_NUM       39
  #define Y5_GPIO_NUM        5
  #define Y4_GPIO_NUM       34
  #define Y3_GPIO_NUM       35
  #define Y2_GPIO_NUM       17
  #define VSYNC_GPIO_NUM    22
  #define HREF_GPIO_NUM     26
  #define PCLK_GPIO_NUM     21

#elif defined(CAMERA_MODEL_AI_THINKER)
  #define PWDN_GPIO_NUM     32
  #define RESET_GPIO_NUM    -1
  #define XCLK_GPIO_NUM      0
  #define SIOD_GPIO_NUM     26
  #define SIOC_GPIO_NUM     27
  
  #define Y9_GPIO_NUM       35
  #define Y8_GPIO_NUM       34
  #define Y7_GPIO_NUM       39
  #define Y6_GPIO_NUM       36
  #define Y5_GPIO_NUM       21
  #define Y4_GPIO_NUM       19
  #define Y3_GPIO_NUM       18
  #define Y2_GPIO_NUM        5
  #define VSYNC_GPIO_NUM    25
  #define HREF_GPIO_NUM     23
  #define PCLK_GPIO_NUM     22
#else
  #error "Camera model not selected"
#endif

static const char* _STREAM_CONTENT_TYPE = "multipart/x-mixed-replace;boundary=" PART_BOUNDARY;
static const char* _STREAM_BOUNDARY = "\r\n--" PART_BOUNDARY "\r\n";
static const char* _STREAM_PART = "Content-Type: image/jpeg\r\nContent-Length: %u\r\n\r\n";

httpd_handle_t stream_httpd = NULL;

static esp_err_t stream_handler(httpd_req_t *req){
  camera_fb_t * fb = NULL;
  esp_err_t res = ESP_OK;
  size_t _jpg_buf_len = 0;
  uint8_t * _jpg_buf = NULL;
  char * part_buf[64];

  res = httpd_resp_set_type(req, _STREAM_CONTENT_TYPE);
  if(res != ESP_OK){
    return res;
  }

  while(true){
    fb = esp_camera_fb_get();
    if (!fb) {
      Serial.println("Camera capture failed");
      res = ESP_FAIL;
    } else {
      if(fb->width > 400){
        if(fb->format != PIXFORMAT_JPEG){
          bool jpeg_converted = frame2jpg(fb, 80, &_jpg_buf, &_jpg_buf_len);
          esp_camera_fb_return(fb);
          fb = NULL;
          if(!jpeg_converted){
            Serial.println("JPEG compression failed");
            res = ESP_FAIL;
          }
        } else {
          _jpg_buf_len = fb->len;
          _jpg_buf = fb->buf;
        }
      }
    }
    if(res == ESP_OK){
      size_t hlen = snprintf((char *)part_buf, 64, _STREAM_PART, _jpg_buf_len);
      res = httpd_resp_send_chunk(req, (const char *)part_buf, hlen);
    }
    if(res == ESP_OK){
      res = httpd_resp_send_chunk(req, (const char *)_jpg_buf, _jpg_buf_len);
    }
    if(res == ESP_OK){
      res = httpd_resp_send_chunk(req, _STREAM_BOUNDARY, strlen(_STREAM_BOUNDARY));
    }
    if(fb){
      esp_camera_fb_return(fb);
      fb = NULL;
      _jpg_buf = NULL;
    } else if(_jpg_buf){
      free(_jpg_buf);
      _jpg_buf = NULL;
    }
    if(res != ESP_OK){
      break;
    }
    //Serial.printf("MJPG: %uB\n",(uint32_t)(_jpg_buf_len));
  }
  return res;
}

void startCameraServer(){
  httpd_config_t config = HTTPD_DEFAULT_CONFIG();
  config.server_port = 80;

  httpd_uri_t index_uri = {
    .uri       = "/",
    .method    = HTTP_GET,
    .handler   = stream_handler,
    .user_ctx  = NULL
  };
  
  //Serial.printf("Starting web server on port: '%d'\n", config.server_port);
  if (httpd_start(&stream_httpd, &config) == ESP_OK) {
    httpd_register_uri_handler(stream_httpd, &index_uri);
  }
}

void setup() {
  WRITE_PERI_REG(RTC_CNTL_BROWN_OUT_REG, 0); //disable brownout detector
 
  Serial.begin(115200);
  Serial.setDebugOutput(false);
  
  camera_config_t config;
  config.ledc_channel = LEDC_CHANNEL_0;
  config.ledc_timer = LEDC_TIMER_0;
  config.pin_d0 = Y2_GPIO_NUM;
  config.pin_d1 = Y3_GPIO_NUM;
  config.pin_d2 = Y4_GPIO_NUM;
  config.pin_d3 = Y5_GPIO_NUM;
  config.pin_d4 = Y6_GPIO_NUM;
  config.pin_d5 = Y7_GPIO_NUM;
  config.pin_d6 = Y8_GPIO_NUM;
  config.pin_d7 = Y9_GPIO_NUM;
  config.pin_xclk = XCLK_GPIO_NUM;
  config.pin_pclk = PCLK_GPIO_NUM;
  config.pin_vsync = VSYNC_GPIO_NUM;
  config.pin_href = HREF_GPIO_NUM;
  config.pin_sccb_sda = SIOD_GPIO_NUM;
  config.pin_sccb_scl = SIOC_GPIO_NUM;
  config.pin_pwdn = PWDN_GPIO_NUM;
  config.pin_reset = RESET_GPIO_NUM;
  config.xclk_freq_hz = 20000000;
  config.pixel_format = PIXFORMAT_JPEG; 
  
  if(psramFound()){
    config.frame_size = FRAMESIZE_UXGA;
    config.jpeg_quality = 10;
    config.fb_count = 2;
  } else {
    config.frame_size = FRAMESIZE_SVGA;
    config.jpeg_quality = 12;
    config.fb_count = 1;
  }
  
  // Camera init
  esp_err_t err = esp_camera_init(&config);
  if (err != ESP_OK) {
    Serial.printf("Camera init failed with error 0x%x", err);
    return;
  }
  // Wi-Fi connection
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("");
  Serial.println("WiFi connected");
  
  Serial.print("Camera Stream Ready! Go to: http://");
  Serial.print(WiFi.localIP());
  
  // Start streaming web server
  startCameraServer();
}

void loop() {
  delay(1);
}

这段代码里 stream_handler 用 multipart/x-mixed-replace 逐帧推 JPEG，浏览器原生支持，所以不用装任何 App。用上面的精简版时留意它的引脚定义：CAMERA_MODEL_AI_THINKER 那组 PWDN 是 32、XCLK 是 0、Y9 是 35，和安信可板子一一对应，别选错型号分支。

五、烧不进去、画面花屏？都是老坑

把社区排障指南里出现频率最高的几个报错按对症关系整理如下：

Failed to connect to ESP32: Timed out waiting for packet header——十有八九是 GPIO0 没接地或者驱动没装好，先查杜邦线再查 CH340 驱动，最后把上传速度降到 115200 重试。
Brownout detector was triggered——供电不足的标志，换独立 5V/2A 电源，别用 USB 口直供。
Camera init failed with error 0x20001——摄像头排线没插紧，掀开连接器卡扣重插一次就好；少数情况是 PSRAM 没检测到。
Sketch too big——分区方案不对，工具菜单里把 Partition Scheme 换成 Huge APP (3MB No OTA)。
画面花屏、条纹、偏色——排线接触不良的另一种表现，轻轻按住摄像头模组再上电，确认无误后用热熔胶固定。

还有一个不报错但很磨人的：长时间连续推流会让 OV2640 明显发热，官方建议长期运行选 SVGA 及以下的 JPEG 分辨率，单张照片才用最大分辨率，间歇采集可以关掉传感器省电降温。

写在最后

十几块钱的板子、四根杜邦线加一个 USB 转 TTL，就能在局域网里跑起一个能拍照能推流的网络摄像头。ESP32-CAM 真正的价值在于给四足、小车这些机器人项目加了一双眼睛——图传跑通之后，下一步接 Home Assistant 做看家监控，或者配合 PIR 传感器做移动侦测抓拍，都是现成的路子。硬件很便宜，坑主要集中在供电和 GPIO0，把这两处记住，剩下的就是复制粘贴的事了。