2013-07-10 252 views
2

攝像頭預覽顯示扭曲的圖像,在縱向模式下拉長,在橫向拉平。我已經用一百萬種技術調整了預覽。然後我在某處閱讀它必須是調整SurfaceView的大小。但到目前爲止我還沒有找到合適的東西。自定義Android攝像頭應用程序,攝像頭預覽問題

這是我activity.java文件:

public class CameraActivity extends Activity { 

private Camera mCamera; 
private CameraPreview mPreview; 
private FrameLayout preview; 
private static final String TAG = "CameraActivity"; 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_camera); 
    if (checkCameraHardware(getBaseContext())){ 
     // Create an instance of Camera 
     mCamera = getCameraInstance(); 
     // Create our Preview view and set it as the content of our activity. 
     mPreview = new CameraPreview(this, mCamera, CameraActivity.this); 
     preview = (FrameLayout) findViewById(R.id.camera_preview); 
     preview.addView(mPreview); 

    } 
} 

/** Check if this device has a camera */ 
private boolean checkCameraHardware(Context context) { 
    if  (context.getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA)){ 
     Log.d(TAG, "Camera Available"); 
     return true; 
    } else { 
     Log.d(TAG, "No Camera Found"); 
     return false; 
    } 
} 

/** A safe way to get an instance of the Camera object. */ 
public Camera getCameraInstance(){ 
    Camera c = null; 
    try { 
     int i = Camera.getNumberOfCameras(); 
     releaseCamera(); //in case camera is being accessed by any other app. 
     Log.d(TAG, "Number of Cameras "+i +"\n"); 
     c = Camera.open(); // attempt to get a Camera instance 
     Log.d(TAG, "Camera Opened"); 
    } 
    catch (Exception e){ 
     Log.d(TAG, "Camera Can't Be Accessed"); 
    } 
    return c; // returns null if camera is unavailable 
} 


@Override 
    protected void onPause() { 
     super.onPause(); 
     releaseCamera();    // release the camera immediately on pause event 
    } 

    private void releaseCamera(){ 
     if (mCamera != null){ 
      //mCamera.setPreviewCallback(null); 
      mPreview.getHolder().removeCallback(mPreview); 
      mCamera.release();  // release the camera for other applications 
     } 
    } 

這是我的攝像頭預覽類:

@SuppressLint("ViewConstructor") 
public class CameraPreview extends SurfaceView implements SurfaceHolder.Callback { 

private static final String TAG = "CameraPreview"; 
private SurfaceHolder mHolder; 
private Camera mCamera; 
private Size mPreviewSize; 

@SuppressWarnings("deprecation") 
public CameraPreview(Context context, Camera camera, Activity activity) { 
    super(context); 
    mCamera = camera; 
    // Install a SurfaceHolder.Callback so we get notified when the 
    // underlying surface is created and destroyed. 
    mHolder = getHolder(); 
    mHolder.addCallback(this); 
    // deprecated setting, but required on Android versions prior to 3.0 
    mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS); 
} 

public void surfaceCreated(SurfaceHolder holder) { 
    // The Surface has been created, now tell the camera where to draw the preview. 

    try { 
     mCamera.setPreviewDisplay(holder); 
     mCamera.startPreview(); 
    } catch (IOException e) { 
     Log.d(TAG, "Error setting camera preview: " + e.getMessage()); 
    } 
} 


public void surfaceDestroyed(SurfaceHolder holder) { 
    // empty. Take care of releasing the Camera preview in your activity. 

} 

public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) { 
    // If your preview can change or rotate, take care of those events here. 
    // Make sure to stop the preview before resizing or reformatting it. 

    if (mHolder.getSurface() == null){ 
     // preview surface does not exist 
     return; 
    } 

    // stop preview before making changes 
    try{ 
      mCamera.stopPreview(); 
     } catch (Exception e){ 
      // ignore: tried to stop a non-existent preview 
     } 


    // set preview size and make any resize, rotate or 
    // reformatting changes here 
    Camera.Parameters parameters = mCamera.getParameters(); 
    List<Size> localSizes = mCamera.getParameters().getSupportedPreviewSizes(); 
    mPreviewSize = localSizes.get(0); 
    Log.d(TAG, "Width " + mPreviewSize.width); 
    Log.d(TAG, "Height " + mPreviewSize.height); 

    parameters.setPreviewSize(mPreviewSize.width, mPreviewSize.height); 
    requestLayout(); 
    mCamera.setParameters(parameters); 

    //start preview with new settings 
    try { 
      mCamera.setPreviewDisplay(mHolder); 
      mCamera.startPreview(); 
    } catch (Exception e){ 
     Log.d(TAG, "Error starting camera preview: " + e.getMessage()); 
    } 
} 


public static void setCameraDisplayOrientation(Activity activity, 
     int cameraId, android.hardware.Camera camera) { 
    android.hardware.Camera.CameraInfo info = 
      new android.hardware.Camera.CameraInfo(); 
    android.hardware.Camera.getCameraInfo(cameraId, info); 
    int rotation = activity.getWindowManager().getDefaultDisplay() 
      .getRotation(); 
    int degrees = 0; 
    switch (rotation) { 
     case Surface.ROTATION_0: degrees = 0; break; 
     case Surface.ROTATION_90: degrees = -90; break; 
     case Surface.ROTATION_180: degrees = 0; break; 
     case Surface.ROTATION_270: degrees = -90; break; 
    } 
    int result; 
    if (info.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) { 
     result = (info.orientation + degrees) % 360; 
     result = (360 - result) % 360; // compensate the mirror 
    } else { // back-facing 
     result = (info.orientation - degrees + 360) % 360; 
    } 
     camera.setDisplayOrientation(result); 
    } 


    } 

這是我activity.xml:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
xmlns:tools="http://schemas.android.com/tools" 
android:baselineAligned="false" 
android:layout_width="match_parent" 
android:layout_height="match_parent" 

tools:context=".CameraActivity" > 

<FrameLayout 
android:id="@+id/camera_preview" 
android:layout_width="0dip" 
android:layout_height="wrap_content" 
android:layout_weight = "1" 
/> 


</LinearLayout> 
+0

是這個問題就解決了? – naresh

回答

1

SurfaceView (或TextureView)必須與您的預覽圖像具有相同的縱橫比,否則您將獲得你描述的失真。

FWIW,你可能發現它與my CWAC-Camera library一起工作很有用,它提供了一個CameraFragment,它可以爲你處理很多低級別的東西。不過,這仍然是一項正在進行的工作。

+0

我的表面視圖具有相同的寬高比。 – Haleema

+0

@ user1235240:不是我能看到的。 'CameraPreview'選擇一個半隨機預覽尺寸,然後似乎只使用它來配置相機。使用該預覽尺寸,我無法看到任何影響「CameraPreview」本身縱橫比的地方。 – CommonsWare

1

創建相機實例後,您可以在onCreate中立即找到相機預覽寬度&高度。然後,選擇layout_widthlayout_height,以便它們適合框架佈局並保留相機的寬高比。您可以使用FrameLayout.addView(View, LayoutParams)

+0

我是否指定了layout_width和layout_height?因爲我在xml中提到它必須fill_parent。 – Haleema

+0

是的,你可能更喜歡在運行時選擇它們,而不是在xml中。 –

+0

我習慣了相機參數來獲取寬度和高度,並相應地設置它,並按照您所述添加它們。但它仍然沒有效果。現在,由於我在Manifest文件中添加了cameraorientation:portrait,所以在橫向模式下工作正常,但是當我使相機垂直時,它全部拉伸。 – Haleema

0

不知道是否有人仍然讀這個,但我有同樣的問題,並修復它this answer。 我在這裏複製的代碼,以防萬一(我也editted它來搭配這個例子):

mCamera.Parameters parameters1 = mCamera.getParameters(); 
parameters1.setPreviewSize(getWidth(), getHeight()); 
mCamera.setParameters(parameters1); 

在此之前只需要添加這些行:

mCamera.startPreview(); 
+0

不幸的是,大多數設備不支持任意預覽大小。 –