Android EXIF

5185 ワード

いくつかのsampleコードを探していますが、とりあえず記録してください。今後の参考になりやすいです。
以下の参照コードは正確性を保証しません。考え方を提供するだけです。
(1) http://stackoverflow.com/questions/12726860/android-how-to-detect-the-image-orientation-portrait-or-landscape-picked-fro
public int getCameraPhotoOrientation(Context context, Uri imageUri, String imagePath){
    int rotate = 0;
    try {
        context.getContentResolver().notifyChange(imageUri, null);
        File imageFile = new File(imagePath);

        ExifInterface exif = new ExifInterface(imageFile.getAbsolutePath());
        int orientation = exif.getAttributeInt(ExifInterface.TAG_ORIENTATION, ExifInterface.ORIENTATION_NORMAL);

        switch (orientation) {
        case ExifInterface.ORIENTATION_ROTATE_270:
            rotate = 270;
            break;
        case ExifInterface.ORIENTATION_ROTATE_180:
            rotate = 180;
            break;
        case ExifInterface.ORIENTATION_ROTATE_90:
            rotate = 90;
            break;
        }

        Log.i("RotateImage", "Exif orientation: " + orientation);
        Log.i("RotateImage", "Rotate value: " + rotate);
    } catch (Exception e) {
        e.printStackTrace();
    }
    return rotate;
}
(2) http://stackoverflow.com/questions/3647993/android-bitmaps-loaded-from-gallery-are-rotated-in-imageview
ファースト あなた need ト create an ExifInterface
ExifInterface exif = new ExifInterface(filename);
You can then grab the orentation of theイメージ

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);
This a full solution.It has the advantage of not needing access to the file itself.This is extremilly useful the Facebook SDK.It has the advantage of not needing access to the file itself.This is is extremilly useful of the are loading image the the the marge the the the the the the contense loading the the the contentage of the contentrom the contentrerererere
public static int getOrientation(Context context, Uri photoUri) {
    /* it's on the external media. */
    Cursor cursor = context.getContentResolver().query(photoUri,
            new String[] { MediaStore.Images.ImageColumns.ORIENTATION }, null, null, null);

    if (cursor.getCount() != 1) {
        return -1;
    }

    cursor.moveToFirst();
    return cursor.getInt(0);
}
And then you can get a rotated Bitmap as follows.This code also scales down the mage(badyunfortunally)to MAX_IMAGE_DIMENSION.Otherwise you may run out of memory.
public static Bitmap getCorrectlyOrientedImage(Context context, Uri photoUri) throws IOException {
    InputStream is = context.getContentResolver().openInputStream(photoUri);
    BitmapFactory.Options dbo = new BitmapFactory.Options();
    dbo.inJustDecodeBounds = true;
    BitmapFactory.decodeStream(is, null, dbo);
    is.close();

    int rotatedWidth, rotatedHeight;
    int orientation = getOrientation(context, photoUri);

    if (orientation == 90 || orientation == 270) {
        rotatedWidth = dbo.outHeight;
        rotatedHeight = dbo.outWidth;
    } else {
        rotatedWidth = dbo.outWidth;
        rotatedHeight = dbo.outHeight;
    }

    Bitmap srcBitmap;
    is = context.getContentResolver().openInputStream(photoUri);
    if (rotatedWidth > MAX_IMAGE_DIMENSION || rotatedHeight > MAX_IMAGE_DIMENSION) {
        float widthRatio = ((float) rotatedWidth) / ((float) MAX_IMAGE_DIMENSION);
        float heightRatio = ((float) rotatedHeight) / ((float) MAX_IMAGE_DIMENSION);
        float maxRatio = Math.max(widthRatio, heightRatio);

        // Create the bitmap from file
        BitmapFactory.Options options = new BitmapFactory.Options();
        options.inSampleSize = (int) maxRatio;
        srcBitmap = BitmapFactory.decodeStream(is, null, options);
    } else {
        srcBitmap = BitmapFactory.decodeStream(is);
    }
    is.close();

    /*
     * if the orientation is not 0 (or -1, which means we don't know), we
     * have to do a rotation.
     */
    if (orientation > 0) {
        Matrix matrix = new Matrix();
        matrix.postRotate(orientation);

        srcBitmap = Bitmap.createBitmap(srcBitmap, 0, 0, srcBitmap.getWidth(),
                srcBitmap.getHeight(), matrix, true);
    }

    return srcBitmap;
}