esp32cam和安卓app通信的代码

下面是ESP32-CAM和安卓APP通信的代码示例。

首先，你需要在ESP32-CAM上安装一个Web服务器，并在其中设置一个API端点以接收来自APP的请求。以下是一个简单的Web服务器示例：

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

// Replace with your network credentials
const char* ssid = "your_SSID";
const char* password = "your_PASSWORD";

// Create an instance of the web server
WebServer server(80);

void setup() {
  // Start the serial communication
  Serial.begin(115200);

  // Connect to Wi-Fi network with SSID and password
  Serial.print("Connecting to ");
  Serial.println(ssid);
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi...");
  }

  // Print the ESP32-CAM IP address
  Serial.println(WiFi.localIP());

  // Initialize the camera
  camera_config_t config;
  config.ledc_channel = LEDC_CHANNEL_0;
  config.ledc_timer = LEDC_TIMER_0;
  config.pin_d0 = 5;
  config.pin_d1 = 18;
  config.pin_d2 = 19;
  config.pin_d3 = 21;
  config.pin_d4 = 36;
  config.pin_d5 = 39;
  config.pin_d6 = 34;
  config.pin_d7 = 35;
  config.pin_xclk = 0;
  config.pin_pclk = 22;
  config.pin_vsync = 25;
  config.pin_href = 23;
  config.pin_sscb_sda = 26;
  config.pin_sscb_scl = 27;
  config.pin_pwdn = 32;
  config.pin_reset = -1;
  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;
  }
  esp_err_t err = esp_camera_init(&config);
  if (err != ESP_OK) {
    Serial.printf("Camera init failed with error 0x%x", err);
    return;
  }

  // Set the API endpoint to handle requests from the app
  server.on("/capture", HTTP_GET, [](){
    // Capture a photo
    camera_fb_t* fb = esp_camera_fb_get();
    if (!fb) {
      Serial.println("Camera capture failed");
      server.send(500, "text/plain", "Camera capture failed");
      return;
    }

    // Send the photo to the client
    server.sendHeader("Content-Type", "image/jpeg");
    server.sendHeader("Content-Disposition", "inline; filename=capture.jpg");
    server.sendHeader("Cache-Control", "no-cache");
    server.sendHeader("Connection", "close");
    server.sendContent(fb->buf, fb->len);
    server.sendContent("");

    // Release the memory used by the photo
    esp_camera_fb_return(fb);
  });

  // Start the server
  server.begin();
}

void loop() {
  // Handle incoming client requests
  server.handleClient();
}

该示例代码使用ESP32-CAM的相机模块拍摄一张照片，并将其作为JPEG图像发送回客户端。在此示例中，API端点为/capture，其使用HTTP GET请求。当客户端访问API端点时，服务器将捕获照片并将其发送回客户端。

在你的安卓APP中，你可以使用HTTP请求库（如Volley）来发送HTTP GET请求，并使用BitmapFactory类将响应转换为Bitmap对象。以下是一个简单的安卓APP代码示例：

public class MainActivity extends AppCompatActivity {
    private static final String TAG = "MainActivity";
    private static final String ESP32_CAM_URL = "http://esp32-cam.local/capture";

    private ImageView mImageView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // Get a reference to the ImageView
        mImageView = findViewById(R.id.image_view);
    }

    public void capture(View view) {
        // Send an HTTP GET request to the ESP32-CAM API endpoint
        RequestQueue queue = Volley.newRequestQueue(this);
        ImageRequest request = new ImageRequest(
                ESP32_CAM_URL,
                new Response.Listener<Bitmap>() {
                    @Override
                    public void onResponse(Bitmap bitmap) {
                        // Display the captured photo in the ImageView
                        mImageView.setImageBitmap(bitmap);
                    }
                },
                0, 0,
                ImageView.ScaleType.CENTER_CROP,
                Bitmap.Config.RGB_565,
                new Response.ErrorListener() {
                    @Override
                    public void onErrorResponse(VolleyError error) {
                        Log.e(TAG, "Error capturing photo", error);
                        Toast.makeText(MainActivity.this, "Error capturing photo", Toast.LENGTH_SHORT).show();
                    }
                });
        queue.add(request);
    }
}

在此示例中，当用户点击按钮时，应用程序将发送HTTP GET请求到ESP32-CAM的API端点，并将响应显示在ImageView中。你需要确保你的安卓设备与ESP32-CAM连接到同一个Wi-Fi网络中，并且你需要将代码中的ESP32_CAM_URL更改为你的ESP32-CAM的IP地址。