ESP32cam--上传JPEG格式图片到服务器

在这个的基础上ESP32cam–获取图片通过串口传到上位机上修改，并通过TCP、UDP上传到服务器。

连接WiFi、TCP实例

#include <WiFi.h>

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

const IPAddress serverIP(192,168,50,14); //欲访问的地址
uint16_t serverPort = 50037;         //服务器端口号

WiFiClient client; //声明一个客户端对象，用于与服务器进行连接

void setup()
{
    Serial.begin(115200);
    Serial.println();

    WiFi.mode(WIFI_STA);
    WiFi.setSleep(false); //关闭STA模式下wifi休眠，提高响应速度
    WiFi.begin(ssid, password);
    while (WiFi.status() != WL_CONNECTED)
    {
        delay(500);
        Serial.print(".");
    }
    Serial.println("Connected");
    Serial.print("IP Address:");
    Serial.println(WiFi.localIP());
}

void loop()
{
    Serial.println("尝试访问服务器");
    if (client.connect(serverIP, serverPort)) //尝试访问目标地址
    {
        Serial.println("访问成功");

        client.print("Hello world!");                    //向服务器发送数据
        while (client.connected() || client.available()) //如果已连接或有收到的未读取的数据
        {
            if (client.available()) //如果有数据可读取
            {
                String line = client.readStringUntil('\n'); //读取数据到换行符
                Serial.print("读取到数据：");
                Serial.println(line);
                client.write(line.c_str()); //将收到的数据回发
            }
        }
        Serial.println("关闭当前连接");
        client.stop(); //关闭客户端
    }
    else
    {
        Serial.println("访问失败");
        client.stop(); //关闭客户端
    }
    delay(5000);
}

UDP实例

#include <WiFi.h>
#include <WiFiUdp.h> //引用以使用UDP

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

WiFiUDP Udp;                      //创建UDP对象
unsigned int localUdpPort = 2333; //本地端口号

void setup()
{
  Serial.begin(115200);
  Serial.println();

  WiFi.mode(WIFI_STA);
  WiFi.begin(ssid, password);
  while (!WiFi.isConnected())
  {
    delay(500);
    Serial.print(".");
  }
  Serial.println("Connected");
  Serial.print("IP Address:");
  Serial.println(WiFi.localIP());

  Udp.begin(localUdpPort); //启用UDP监听以接收数据
}

void loop()
{
  int packetSize = Udp.parsePacket(); //获取当前队首数据包长度
  if (packetSize)                     //如果有数据可用
  {
    char buf[packetSize];
    Udp.read(buf, packetSize); //读取当前包数据

    Serial.println();
    Serial.print("Received: ");
    Serial.println(buf);
    Serial.print("From IP: ");
    Serial.println(Udp.remoteIP());
    Serial.print("From Port: ");
    Serial.println(Udp.remotePort());

    Udp.beginPacket(Udp.remoteIP(), Udp.remotePort()); //准备发送数据
    Udp.print("Received: ");    //复制数据到发送缓存
    Udp.write((const uint8_t*)buf, packetSize); //复制数据到发送缓存
    Udp.endPacket();            //发送数据
  }
}

---

UDP发送图片

#include "esp_camera.h"
#include <WiFi.h>
#include "AsyncUDP.h"

const char *ssid = "wxy2018";
const char *password = "wxy168168";

AsyncUDP udp;                      //创建UDP对象


int buttonState = 0;
int btnHold = 0;

#define KEY_PIN       15

#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

static camera_config_t camera_config = {
    .pin_pwdn = PWDN_GPIO_NUM,
    .pin_reset = RESET_GPIO_NUM,
    .pin_xclk = XCLK_GPIO_NUM,
    .pin_sscb_sda = SIOD_GPIO_NUM,
    .pin_sscb_scl = SIOC_GPIO_NUM,
    
    .pin_d7 = Y9_GPIO_NUM,
    .pin_d6 = Y8_GPIO_NUM,
    .pin_d5 = Y7_GPIO_NUM,
    .pin_d4 = Y6_GPIO_NUM,
    .pin_d3 = Y5_GPIO_NUM,
    .pin_d2 = Y4_GPIO_NUM,
    .pin_d1 = Y3_GPIO_NUM,
    .pin_d0 = Y2_GPIO_NUM,
    .pin_vsync = VSYNC_GPIO_NUM,
    .pin_href = HREF_GPIO_NUM,
    .pin_pclk = PCLK_GPIO_NUM,
    
    .xclk_freq_hz = 20000000,
    .ledc_timer = LEDC_TIMER_0,
    .ledc_channel = LEDC_CHANNEL_0,
    
    .pixel_format = PIXFORMAT_JPEG,
    .frame_size = FRAMESIZE_XGA,
    .jpeg_quality = 12,
    .fb_count = 1,
};

esp_err_t camera_init() {
    //initialize the camera
    esp_err_t err = esp_camera_init(&camera_config);
    if (err != ESP_OK) {
        Serial.print("Camera Init Failed");
        return err;
    }
    sensor_t * s = esp_camera_sensor_get();
    //initial sensors are flipped vertically and colors are a bit saturated
    if (s->id.PID == OV2640_PID) {
    //        s->set_vflip(s, 1);//flip it back
    //        s->set_brightness(s, 1);//up the blightness just a bit
    //        s->set_contrast(s, 1);
    }
    
    Serial.print("Camera Init OK");
    return ESP_OK;
}

void wifi_init(void)
{
    WiFi.mode(WIFI_STA);
    
//    WiFi.setSleep(false); //关闭STA模式下wifi休眠，提高响应速度
    
    WiFi.begin(ssid, password);
    
    while (WiFi.status() != WL_CONNECTED)
    {
        delay(500);
        Serial.print(".");
    }
    
    Serial.println("Connected");

    Serial.print("IP Address:");
    
    Serial.println(WiFi.localIP());

    if(udp.connect(IPAddress(192,168,0,103), 8888))
    {
        Serial.println("UDP connected");
        udp.print("Hello Server!"); 
    }
}


void setup() {
    Serial.begin(115200);
    
    camera_init(); // 摄像头初始化

    wifi_init(); // WiFi初始化

    pinMode(KEY_PIN, INPUT_PULLUP); //设置按键管脚输入上拉模式

    Serial.println("sys is running!");
}

void loop() 
{
    buttonState = digitalRead(KEY_PIN); //读取按键返回状态值
    if (buttonState == LOW && btnHold == 0)
    { // 若按键被按下
        delay(100); //等待跳过按键抖动的不稳定过程
        if (buttonState == LOW) // 若按键被按下
        {
            Serial.print("click\r\n");
            btnHold = 1;
        
            //acquire a frame
            camera_fb_t * fb = esp_camera_fb_get();
            if (!fb)
            {
                Serial.print( "Camera capture failed");
            }
            else
            { 
                // TODO

                udp.write(fb->buf, fb->len); //复制数据到发送缓存
                

                Serial.println("succes to send image for UDP");
                
                //return the frame buffer back to the driver for reuse
                esp_camera_fb_return(fb);
            }
        }
    }
      
    if (buttonState == HIGH)
    {
        btnHold = 0;
    }
}

按下按键，UDP服务器接收到了JPEG格式的图片了！然而，数据长度却只有1436个字节！看来还要分几个数据包才行啊！