2

我有一个工作代码，它使用后置摄像头捕获图像并将所有内容保存到 SD 卡，但现在我想添加一个前置摄像头来捕获图像而不是后置摄像头

public class CameraExampleActivity extends Activity  {
Camera camera;
Preview preview;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_camera_example);

    preview = new Preview(this);
    ((FrameLayout) findViewById(R.id.preview)).addView(preview);
}

public void click(View v) {
    preview.camera.takePicture(shutterCallback, null, jpegCallback);
}

ShutterCallback shutterCallback = new ShutterCallback() 
{
    public void onShutter() 
    {
        Log.d("Log", "Shuttered");
    }
};

PictureCallback jpegCallback = new PictureCallback() 
{
    public void onPictureTaken(byte[] imgData, Camera camera) 
    {
        //Compressing the image 640*480
        //-----------------------------------------
        Bitmap bmp=BitmapFactory.decodeByteArray(imgData, 0, imgData.length);
        Bitmap resizedBmp = Bitmap.createScaledBitmap(bmp, 640, 480, false);

        ByteArrayOutputStream bos = new ByteArrayOutputStream();
        resizedBmp.compress(CompressFormat.PNG, 0, bos);
        byte[] data = bos.toByteArray();
        //-----------------------------------------


        File pictureFileDir = getDir();

        if (!pictureFileDir.exists() && !pictureFileDir.mkdirs()) {

            Toast.makeText(CameraExampleActivity.this, "Can't create directory to save image.",Toast.LENGTH_LONG).show();
            return;
        }

        String photoFile = "MyPicture.jpg";
        String filename = pictureFileDir.getPath() + File.separator + photoFile;
        File pictureFile = new File(filename);

        try 
        {
            FileOutputStream fos = new FileOutputStream(pictureFile);
            fos.write(data);
            fos.close();
            Toast.makeText(CameraExampleActivity.this, "New Image saved:" + filename,Toast.LENGTH_LONG).show();
        }
        catch (Exception e) {
            Log.d("Error",""+e);
        }
    }
};

private File getDir() 
{
    File sdDir = Environment.getExternalStorageDirectory();
    return new File(sdDir, "Attendance Image");
}
}

预览课

public class Preview extends SurfaceView implements SurfaceHolder.Callback {
private static final String TAG = "Preview";

SurfaceHolder mHolder;
public Camera camera;

Preview(Context context) {
    super(context);

    // Install a SurfaceHolder.Callback so we get notified when the
    // underlying surface is created and destroyed.
    mHolder = getHolder();
    mHolder.addCallback(this);
    mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
}

public void surfaceCreated(SurfaceHolder holder) {
    // The Surface has been created, acquire the camera and tell it where
    // to draw.
    camera = Camera.open();
    try {
        camera.setPreviewDisplay(holder);

        camera.setPreviewCallback(new PreviewCallback() {

            public void onPreviewFrame(byte[] data, Camera arg1) {

                FileOutputStream outStream = null;
                try{
                    outStream = new FileOutputStream("/sdcard/Image.jpg");
                    outStream.write(data);
                    outStream.close();
                } catch (Throwable e){
                    Log.d("CAMERA", e.getMessage());
                } 

                Preview.this.invalidate();
            }
        });
    } catch (IOException e) {
        e.printStackTrace();
    }
}

public void surfaceDestroyed(SurfaceHolder holder) {
    // Surface will be destroyed when we return, so stop the preview.
    // Because the CameraDevice object is not a shared resource, it's very
    // important to release it when the activity is paused.
    camera.stopPreview();
    camera = null;
}

public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
    // Now that the size is known, set up the camera parameters and begin
    // the preview.
    Camera.Parameters parameters = camera.getParameters();
    parameters.setPreviewSize(w, h);
    camera.setParameters(parameters);
    camera.startPreview();
}

  }
4

1 回答 1

4

而不是 use Camera.open()，您需要使用open()带有所需相机 ID 的版本。要查找此 ID，请调用getNumberOfCameras()，Camera遍历它们，并找到Camera.CameraInfo表明它是正面的：

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.GINGERBREAD) {
  Camera.CameraInfo info=new Camera.CameraInfo();

  for (int i=0; i < Camera.getNumberOfCameras(); i++) {
    Camera.getCameraInfo(i, info);

    if (info.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) {
      camera=Camera.open(i);
    }
  }
}

if (camera == null) {
  camera=Camera.open();
}
于 2013-07-04T16:44:43.437 回答