Android ImageView Displaying Rotated Images Although Source Is Not Rotated

Question

I am trying to display gallery images in a gridview, and on image click, open a fullscreen view for the image. The weird thing is, that when the images are displaying in the gallery, they follow the correct rotation. But When I simply query the photos in my custom gallery, they are always rotated by 90 degrees counter clockwise.

I have seen some solutions to rotate using exif interface which will require memory to rotate since it loads the original bitmap and the newly rotated one.

My question is: Why does simply displaying an image from the gallery in an ImageView result in the image being rotated?

Thanks.

this thing is happening because height and width of your selected image is not in proportion to show in its original position — Android is everything for me, Jul 24 '14 at 10:02
Okay I suspected that this is the case. But the problem is that each image has different height and width. So letting them take their respected size in a grid view will make the grid view look irregular. Do you have any suggestions to make it look symmetric and show the correct rotation at the same time? — Pacemaker, Jul 24 '14 at 10:31

score 1 · Answer 1 · answered Jul 24 '14 at 10:06

First you need to create an ExifInterface:

ExifInterface exif = new ExifInterface(filename);

You can then grab the orientation of the image:

orientation = exif.getAttributeInt(ExifInterface.TAG_ORIENTATION, 1);

Here's what the orientation values mean: http://sylvana.net/jpegcrop/exif_orientation.html

So, the most important values are 3, 6 and 8. If the orientation is 6, for example, you can rotate the image like this:

 Matrix matrix = new Matrix();
matrix.postRotate(90);
rotatedBitmap = Bitmap.createBitmap(sourceBitmap, 0, 0, sourceBitmap.getWidth(),       sourceBitmap.getHeight(), matrix, true);

Hi, Thanks for the solution. But I am trying to avoid loading two bitmaps as this will give me an OutOfMemoryError. — Pacemaker, Jul 24 '14 at 10:33

Santhosh · Answer 2 · 2014-07-24T10:44:51.720

Try like this you can avoid OOM Error refer Load Bitmap Effieiently and Whatsapp bitmap loading

public static int calculateInSampleSize(BitmapFactory.Options options,
                int reqWidth, int reqHeight) {
            // Raw height and width of image
            final int height = options.outHeight;
            final int width = options.outWidth;
            int inSampleSize = 1;

            if (height > reqHeight || width > reqWidth) {

                final int halfHeight = height / 2;
                final int halfWidth = width / 2;

                // Calculate the largest inSampleSize value that is a power of 2 and
                // keeps both
                // height and width larger than the requested height and width.
                while ((halfHeight / inSampleSize) > reqHeight
                        && (halfWidth / inSampleSize) > reqWidth) {
                    inSampleSize *= 2;
                }
            }
            return inSampleSize;
        }


    public static Bitmap decodeSampledBitmapFromResource(Resources res,
                int resId, int reqWidth, int reqHeight) {
            // First decode with inJustDecodeBounds=true to check dimensions
            final BitmapFactory.Options options = new BitmapFactory.Options();
            options.inJustDecodeBounds = true;
            BitmapFactory.decodeResource(res, resId, options);
            // Calculate inSampleSize
            options.inSampleSize = calculateInSampleSize(options, reqWidth,
                    reqHeight);
            // Decode bitmap with inSampleSize set
            options.inJustDecodeBounds = false;
            return BitmapFactory.decodeResource(res, resId, options);
        }

Check the rotation of the Image and display it properly...as

    scaledBitmap=decodeSampledBitmapFromResource(.....);
    ExifInterface exif=null;
            try {
                exif = new ExifInterface(filePath);
                int orientation = exif.getAttributeInt(
                        ExifInterface.TAG_ORIENTATION, 0);
                Log.d("EXIF", "Exif: " + orientation);
                Matrix matrix = new Matrix();
                if (orientation == 6) {
                    matrix.postRotate(90);
                    Log.d("EXIF", "Exif: " + orientation);
                } else if (orientation == 3) {
                    matrix.postRotate(180);
                    Log.d("EXIF", "Exif: " + orientation);
                } else if (orientation == 8) {
                    matrix.postRotate(270);
                    Log.d("EXIF", "Exif: " + orientation);
                }
                scaledBitmap = Bitmap.createBitmap(scaledBitmap, 0, 0,
                        scaledBitmap.getWidth(), scaledBitmap.getHeight(), matrix,
                        true);
            } catch (IOException e) {
                e.printStackTrace();
            }

Okay this looks like a nice solution. As far as I can see, it does not require loading the original bitmap, correct? Because if it does this will probably give me an OutOfMemoryError. — Pacemaker, Jul 24 '14 at 10:32
The line : scaledBitmap = Bitmap.createBitmap(scaledBitmap, 0, 0, scaledBitmap.getWidth(), scaledBitmap.getHeight(), matrix, true); has a mistake, shouldn't the first parameter be the original bitmap? — Pacemaker, Jul 24 '14 at 10:34

Android ImageView Displaying Rotated Images Although Source Is Not Rotated

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