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How to rotate and flip a bitmap in onPictureTaken

I find onPictureTakenthat the saved bitmap is flipped about the y axis and rotated 90 degrees clockwise, even if there was no camera preview. My Nexus S runs 2.3.6. The same program that runs on my Nexus 4 with 4.2 has a resulting bitmap that is flipped around the y axis and rotated 180 degrees clockwise.

This is the code I run in onPictureTaken:

@Override
public void onPictureTaken(final byte[] data, Camera camera) {
    Bitmap picture = BitmapFactory.decodeByteArray(data, 0, data.length);
    String path = MediaStore.Images.Media.insertImage(getContentResolver(), picture, "name" , "description");
    Log.e("tag", "path: " + path); // prints something like "path: content://media/external/images/media/819"

    try {
        ExifInterface exif = new ExifInterface(path); // prints this error: "04-25 21:28:21.063: E/JHEAD(12201): can't open 'content://media/external/images/media/819'"
        int orientation = exif.getAttributeInt(ExifInterface.TAG_ORIENTATION, ExifInterface.ORIENTATION_NORMAL);
        Log.e("tag", "exif orientation: " + orientation); // this is outputting orientation unknown
    } catch (IOException e) {
        e.printStackTrace();
    }
}

Can someone show me how I fix this, given that it seems I am getting different results from different devices? How to determine the orientation of the resulting bitmap so that I know that it rotates it 90 or 180 degrees counterclockwise?

[EDIT]

, ExifInterface, , , , ...

+2
3

, . Motorola Devy, Samsung Xcover 1 Samsung XCover 2.

, . 1. . 2. , , onPictureTaken, , , .

1

private void initPreview(int width, int height) {
    if (camera != null && holder.getSurface() != null) {
        try {
            camera.setPreviewDisplay(holder);
        } catch (Throwable t) {
            Log.e("PreviewDemo-surfaceCallback",
              "Exception in setPreviewDisplay()", t);
            Toast.makeText(getContext(), t.getMessage(),
                       Toast.LENGTH_LONG).show();
        }

        try {
            Camera.Parameters parameters=camera.getParameters();

            Camera.Size size=getBestPreviewSize(width, height, parameters);
            Camera.Size pictureSize=getSmallestPictureSize(parameters);

            Display display = windowManager.getDefaultDisplay();
            if (Build.VERSION.SDK_INT < Build.VERSION_CODES.FROYO) { // for 2.1 and before
                if (isPortrait(display)) {
                    parameters.set(CAMERA_PARAM_ORIENTATION, CAMERA_PARAM_PORTRAIT);
                } else {
                    parameters.set(CAMERA_PARAM_ORIENTATION, CAMERA_PARAM_LANDSCAPE);
                }
            } else { // for 2.2 and later
                switch (display.getRotation()) {
                    case Surface.ROTATION_0: // This is display orientation
                        if (size.height > size.width) parameters.setPreviewSize(size.height, size.width);
                        else parameters.setPreviewSize(size.width, size.height);
                        camera.setDisplayOrientation(90);
                        break;
                    case Surface.ROTATION_90:
                        if (size.height > size.width) parameters.setPreviewSize(size.height, size.width);
                        else parameters.setPreviewSize(size.width, size.height);
                        camera.setDisplayOrientation(0);
                        break;
                    case Surface.ROTATION_180:
                        if (size.height > size.width) parameters.setPreviewSize(size.height, size.width);
                        else parameters.setPreviewSize(size.width, size.height);
                        camera.setDisplayOrientation(270);
                        break;
                    case Surface.ROTATION_270:
                        if (size.height > size.width) parameters.setPreviewSize(size.height, size.width);
                        else parameters.setPreviewSize(size.width, size.height);
                        camera.setDisplayOrientation(180);
                        break;
                }
            }

            parameters.setPictureSize(pictureSize.width, pictureSize.height);
            //parameters.setPictureFormat(ImageFormat.JPEG);
            camera.setParameters(parameters);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

"surfaceChanged" (SurfaceView) :

public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
        stopPreview();
        initPreview(w, h);
        startPreview();
    }

stopPreview:

private void stopPreview() {
    if (camera != null) {
        camera.stopPreview();
    }
}

startPreview:

private void startPreview() {
    if (camera != null) {
        camera.startPreview();
    }
}

2

onPictureTaken , :

Display display = getWindowManager().getDefaultDisplay();
    int rotation = 0;
    switch (display.getRotation()) {
        case Surface.ROTATION_0: // This is display orientation
        rotation = 90;
        break;
    case Surface.ROTATION_90:
        rotation = 0;
        break;
    case Surface.ROTATION_180:
        rotation = 270;
        break;
    case Surface.ROTATION_270:
        rotation = 180;
            break;
     }

     Bitmap bitmap = BitmapTools.toBitmap(data);
     bitmap = BitmapTools.rotate(bitmap, rotation);

BitmapTools.java

public class BitmapTools {

        public static Bitmap toBitmap(byte[] data) {
            return BitmapFactory.decodeByteArray(data , 0, data.length);
        }

        public static Bitmap rotate(Bitmap in, int angle) {
            Matrix mat = new Matrix();
            mat.postRotate(angle);
            return Bitmap.createBitmap(in, 0, 0, in.getWidth(), in.getHeight(), mat, true);
        }
    }
+14

, , , , (bitmap.getWidth > bitmap.getHeight())

public static int getExifRotation(String imgPath) 
    {
        try 
        {
            ExifInterface exif = new ExifInterface(imgPath);
            String rotationAmount = exif.getAttribute(ExifInterface.TAG_ORIENTATION);
            if (!TextUtils.isEmpty(rotationAmount)) 
            {
                int rotationParam = Integer.parseInt(rotationAmount);
                switch (rotationParam) 
                {
                    case ExifInterface.ORIENTATION_NORMAL:
                        return 0;
                    case ExifInterface.ORIENTATION_ROTATE_90:
                        return 90;
                    case ExifInterface.ORIENTATION_ROTATE_180:
                        return 180;
                    case ExifInterface.ORIENTATION_ROTATE_270:
                        return 270;
                    default:
                        return 0;
                }
            } 
            else 
            {
                return 0;
            }
        }
        catch (Exception ex) 
        {
            return 0;
        }
    }
0

ExifInterface, .

I have this feature in my application to check the weather image taken from the camera, to rotate or not.

      if(ExifNeedsRotate(GetPathFromUri(context, selectedImage))){
    // Rotate your bitmap using the Matrix
     }


public static boolean ExifNeedsRotate(String paramString){

      if (android.os.Build.VERSION.SDK_INT >= 5){

          try
          {

                Class localClass = Class.forName("android.media.ExifInterface");
                Class[] arrayOfClass1 = new Class[1];
                arrayOfClass1[0] = String.class;
                Constructor localConstructor = localClass.getConstructor(arrayOfClass1);
                Class[] arrayOfClass2 = new Class[1];
                arrayOfClass2[0] = String.class;
                Method localMethod = localClass.getMethod("getAttribute", arrayOfClass2);
                Object[] arrayOfObject1 = new Object[1];
                arrayOfObject1[0] = paramString;
                Object localObject1 = localConstructor.newInstance(arrayOfObject1);
                Object[] arrayOfObject2 = new Object[1];
                arrayOfObject2[0] = "Orientation";
                Object localObject2 = localMethod.invoke(localObject1, arrayOfObject2);
                if (localObject2 != null){
                      boolean bool = localObject2.equals("6");
                      if (bool)
                         return true;
                }

          }
          catch (Exception localException){
              return false;
          }

    }

    return false;

}

Go to ImageUri as an input.

 public static String GetPathFromUri(Context paramContext, Uri paramUri)
  {
       String str;
       try
       {
            if (paramUri.toString().startsWith("file:")){
                    str = paramUri.getPath();
            }
            else
            {
                    str = null;
                    String[] arrayOfString = new String[1];
                    arrayOfString[0] = "_data";
                    Cursor localCursor = paramContext.getContentResolver().query(paramUri, arrayOfString, null, null, null);
                    if (localCursor != null)
                    {
                            localCursor.moveToFirst();
                            int i = localCursor.getColumnIndex(arrayOfString[0]);
                            if ((localCursor.getCount() >= 1) && (localCursor.getColumnCount() >= i + 1))
                                str = localCursor.getString(i);
                            localCursor.close();
                    }
            }

      }
      catch (Exception localException){
          str = null;
      }

      return str;
  }
0
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