我正在捕捉图像并将其设置为图像视图。

public void captureImage() {

    Intent intentCamera = new Intent("android.media.action.IMAGE_CAPTURE");
    File filePhoto = new File(Environment.getExternalStorageDirectory(), "Pic.jpg");
    imageUri = Uri.fromFile(filePhoto);
    MyApplicationGlobal.imageUri = imageUri.getPath();
    intentCamera.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
    startActivityForResult(intentCamera, TAKE_PICTURE);
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent intentFromCamera) {
    super.onActivityResult(requestCode, resultCode, intentFromCamera);

    if (resultCode == RESULT_OK && requestCode == TAKE_PICTURE) {

        if (intentFromCamera != null) {
            Bundle extras = intentFromCamera.getExtras();
            if (extras.containsKey("data")) {
                bitmap = (Bitmap) extras.get("data");
            }
            else {
                bitmap = getBitmapFromUri();
            }
        }
        else {
            bitmap = getBitmapFromUri();
        }
        // imageView.setImageBitmap(bitmap);
        imageView.setImageURI(imageUri);
    }
    else {
    }
}

public Bitmap getBitmapFromUri() {

    getContentResolver().notifyChange(imageUri, null);
    ContentResolver cr = getContentResolver();
    Bitmap bitmap;

    try {
        bitmap = android.provider.MediaStore.Images.Media.getBitmap(cr, imageUri);
        return bitmap;
    }
    catch (Exception e) {
        e.printStackTrace();
        return null;
    }
}

但问题是,某些设备上的图像每次旋转时。例如,在三星设备上,它工作得很好,但在索尼Xperia上,图像旋转了90度,在东芝Thrive(平板电脑)上旋转了180度。


当前回答

我根据@Jason Robinson的回答创建了一个Kotlin扩展函数,简化了Kotlin开发人员的操作。我希望这能有所帮助。

fun Bitmap.fixRotation(uri: Uri): Bitmap? {

    val ei = ExifInterface(uri.path)

    val orientation: Int = ei.getAttributeInt(
        ExifInterface.TAG_ORIENTATION,
        ExifInterface.ORIENTATION_UNDEFINED
    )

    return when (orientation) {
        ExifInterface.ORIENTATION_ROTATE_90 -> rotateImage( 90f)
        ExifInterface.ORIENTATION_ROTATE_180 -> rotateImage( 180f)
        ExifInterface.ORIENTATION_ROTATE_270 -> rotateImage( 270f)
        ExifInterface.ORIENTATION_NORMAL -> this
        else -> this
    }
}

fun Bitmap.rotateImage(angle: Float): Bitmap? {
    val matrix = Matrix()
    matrix.postRotate(angle)
    return Bitmap.createBitmap(
        this, 0, 0, width, height,
        matrix, true
    )
}

其他回答

通常建议使用ExifInterface解决问题,就像@Jason Robinson所建议的那样。如果这种方法不起作用,你可以试着查找最新拍摄的图像的方向…

private int getImageOrientation(){
    final String[] imageColumns = { MediaStore.Images.Media._ID, MediaStore.Images.ImageColumns.ORIENTATION };
    final String imageOrderBy = MediaStore.Images.Media._ID+" DESC";
    Cursor cursor = getContentResolver().query(MediaStore.Images.Media.EXTERNAL_CONTENT_URI,
            imageColumns, null, null, imageOrderBy);

    if(cursor.moveToFirst()){
        int orientation = cursor.getInt(cursor.getColumnIndex(MediaStore.Images.ImageColumns.ORIENTATION));
        cursor.close();
        return orientation;
    } else {
        return 0;
    }
}

最好试着以特定的方向照相。

android:screenOrientation="landscape"
android:configChanges="orientation|keyboardHidden"

为了获得最好的结果,在cameraview活动中给出景观方向。

如果有人在Android 4.4 (KitKat)上使用ExifInterface获得方向时遇到问题,这可能是因为从URI获得了错误的路径。在堆栈溢出问题中看到一个解决方案,从URI获得真正的路径,Android奇巧新的存储访问框架

可悲的是,上面的@jason-robinson回答对我没用。

虽然旋转函数工作得很完美:

public static Bitmap rotateImage(Bitmap source, float angle) {
    Matrix matrix = new Matrix();
    matrix.postRotate(angle);
    return Bitmap.createBitmap(source, 0, 0, source.getWidth(), source.getHeight(), matrix,
            true);
}

我必须做以下事情来获得方向,因为Exif方向总是0

protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode,resultCode,data);
    if (requestCode == RESULT_LOAD_IMAGE && resultCode == RESULT_OK && data != null) {
            Uri selectedImage = data.getData();
            String[] orientationColumn = {MediaStore.Images.Media.ORIENTATION};
            Cursor cur = managedQuery(imageUri, orientationColumn, null, null, null);
            int orientation = -1;
            if (cur != null && cur.moveToFirst()) {
                    orientation = cur.getInt(cur.getColumnIndex(orientationColumn[0]));
            }
            InputStream imageStream = getContentResolver().openInputStream(selectedImage);
            Bitmap bitmap = BitmapFactory.decodeStream(imageStream);
            switch(orientation) {
                    case 90:
                            bitmap = rotateImage(chosen_image_bitmap, 90);
                            break;
                    case 180:
                            bitmap = rotateImage(chosen_image_bitmap, 180);
                            break;
                    case 270:
                            bitmap = rotateImage(chosen_image_bitmap, 270);
                            break;
                    default:
                            break;
            }
            imageView.setImageBitmap(bitmap );

如果你用的是Fresco,你可以用这个

final ImageRequest imageRequest = ImageRequestBuilder.newBuilderWithSource(uri)
.setRotationOptions(RotationOptions.autoRotate())
.build();

mSimpleDraweeView.setController(
Fresco.newDraweeControllerBuilder()
    .setImageRequest(imageRequest)
    .build());

这将根据Exif数据自动旋转图像。

来源:https://frescolib.org/docs/rotation.html