Android studio 中调用摄像头录像

要在 Android Studio 中调用摄像头录像，需要使用 Android 的 Camera API 或 CameraX API（推荐）。以下是使用 CameraX API 实现摄像头录像的基本步骤：

使用 CameraX API 实现摄像头录像步骤：

1. 添加依赖： 在 build.gradle 文件中添加 CameraX 的依赖：

   gradle
   复制代码
   dependencies {
       def camerax_version = "1.1.0-alpha10"
       implementation "androidx.camera:camera-core:$camerax_version"
       implementation "androidx.camera:camera-camera2:$camerax_version"
       implementation "androidx.camera:camera-lifecycle:$camerax_version"
   }
   

2. 在 XML 布局中添加预览视图： 在你的布局文件中添加 PreviewView，用于显示摄像头预览：

   xml
   复制代码
   <androidx.camera.view.PreviewView
       android:id="@+id/previewView"
       android:layout_width="match_parent"
       android:layout_height="match_parent" />
   

3. 设置 CameraX 用例： 在 Activity 或 Fragment 中配置和启动 CameraX 用例，包括预览和录像：

   java
   复制代码
   import androidx.camera.core.CameraSelector;
   import androidx.camera.core.Preview;
   import androidx.camera.core.VideoCapture;
   import androidx.camera.lifecycle.ProcessCameraProvider;
   import androidx.camera.view.PreviewView;
   import androidx.core.content.ContextCompat;
   import java.io.File;
   import java.text.SimpleDateFormat;
   import java.util.Locale;
   
   public class CameraActivity extends AppCompatActivity {
       private PreviewView previewView;
       private VideoCapture videoCapture;
       private File outputDirectory;
       private String currentVideoPath;
   
       @Override
       protected void onCreate(Bundle savedInstanceState) {
           super.onCreate(savedInstanceState);
           setContentView(R.layout.activity_camera);
   
           previewView = findViewById(R.id.previewView);
           outputDirectory = getOutputDirectory();
   
           startCamera();
       }
   
       private void startCamera() {
           ListenableFuture<ProcessCameraProvider> cameraProviderFuture = ProcessCameraProvider.getInstance(this);
   
           cameraProviderFuture.addListener(() -> {
               try {
                   ProcessCameraProvider cameraProvider = cameraProviderFuture.get();
   
                   Preview preview = new Preview.Builder().build();
                   preview.setSurfaceProvider(previewView.getSurfaceProvider());
   
                   videoCapture = new VideoCapture.Builder()
                           .setTargetRotation(previewView.getDisplay().getRotation())
                           .build();
   
                   CameraSelector cameraSelector = CameraSelector.DEFAULT_BACK_CAMERA;
   
                   cameraProvider.unbindAll();
                   cameraProvider.bindToLifecycle(this, cameraSelector, preview, videoCapture);
   
               } catch (Exception e) {
                   e.printStackTrace();
               }
           }, ContextCompat.getMainExecutor(this));
       }
   
       private File getOutputDirectory() {
           File mediaDir = new File(getExternalFilesDir(null), "Videos");
           if (!mediaDir.exists()) {
               mediaDir.mkdirs();
           }
           return mediaDir;
       }
   
       private File createFile() {
           String timestamp = new SimpleDateFormat("yyyyMMdd_HHmmss", Locale.getDefault()).format(System.currentTimeMillis());
           String prepend = "VIDEO_" + timestamp + "_";
           File videoFile = new File(outputDirectory, prepend + ".mp4");
           currentVideoPath = videoFile.getAbsolutePath();
           return videoFile;
       }
   
       private void startRecording() {
           File videoFile = createFile();
   
           videoCapture.startRecording(videoFile, ContextCompat.getMainExecutor(this), new VideoCapture.OnVideoSavedCallback() {
               @Override
               public void onVideoSaved(@NonNull OutputFileResults outputFileResults) {
                   String msg = "Video saved: " + currentVideoPath;
                   Toast.makeText(CameraActivity.this, msg, Toast.LENGTH_SHORT).show();
               }
   
               @Override
               public void onError(int videoCaptureError, @NonNull String message, @Nullable Throwable cause) {
                   String msg = "Video capture failed: " + message;
                   Toast.makeText(CameraActivity.this, msg, Toast.LENGTH_SHORT).show();
               }
           });
       }
   
       private void stopRecording() {
           videoCapture.stopRecording();
       }
   
       // Add methods to handle recording start/stop based on user interaction
   }
   

4. 录像控制：

   • 使用 startRecording() 方法开始录像，并通过 stopRecording() 方法停止录像。
   • 可以根据需要添加用户交互控制，例如按钮点击开始和停止录像。

通过上述步骤，你可以在 Android 应用中使用 CameraX API 实现摄像头录像功能，并根据需求进行定制和优化。

关键字：

Android, CameraX API, 摄像头录像, PreviewView, VideoCapture, 录像功能