android - 在 imageview 中使用时从相机或画廊拍摄的图片其方向发生变化，有时在 Android 中会垂直拉伸

Question

在我的应用程序中，我必须从相机捕获图像或从图库导入，在活动的 imageview 中显示它。一切都很好，我从两者都得到图像，并且能够毫无例外地在 imageview 上设置它。但有时图像无法正确缩放并垂直拉伸或改变方向。请帮帮我。

这是我从官方 android 文档中引用的解码图像的代码：

public static Bitmap decodeSampledBitmapFromResource(File photoFile, int reqWidth, int reqHeight) {

    // First decode with inJustDecodeBounds=true to check dimensions
    final BitmapFactory.Options options = new BitmapFactory.Options();
    options.inJustDecodeBounds = true;
    try {
        BitmapFactory.decodeStream(new FileInputStream(photoFile), null,
                options);

        // Calculate inSampleSize
        options.inSampleSize = calculateInSampleSize(options, reqWidth,
                reqHeight);

        // Decode bitmap with inSampleSize set
        options.inJustDecodeBounds = false;

        return BitmapFactory.decodeStream(new FileInputStream(photoFile),
                null, options);

    } catch (FileNotFoundException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
        return null;
    }
}

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) {

        // Calculate ratios of height and width to requested height and
        // width
        final int heightRatio = Math.round((float) height
                / (float) reqHeight);
        final int widthRatio = Math.round((float) width / (float) reqWidth);

        // Choose the smallest ratio as inSampleSize value, this will
        // guarantee
        // a final image with both dimensions larger than or equal to the
        // requested height and width.
        inSampleSize = heightRatio < widthRatio ? heightRatio : widthRatio;
    }

    return inSampleSize;
}

Answer 1

图像具有不同的方向，因此在放置 imageview 时它会根据方向旋转。您可以从图像的属性中检查照片的方向。要以正确的方式设置图像，您可以使用以下代码...

     int rot=getCameraPhotoOrientation(this,Uri,picturePath);
         if(rot!=0)
         bitmap=new RotateOrientation().RotateOrientationCall(bitmap,rot);

getCameraPhotoOrientation方法：-

 public static 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.d(TAG, "Exit orientation: " + orientation);
     } catch (Exception e) {
         e.printStackTrace();
     }
    return rotate;
 }

添加RotateOrientation类以根据方向旋转类。

 public class RotateOrientation  {

Bitmap RotateOrientationCall(Bitmap src,float degree)
        {


        Matrix matrix=new Matrix();
        matrix.postRotate(degree);
       Bitmap bmOut = Bitmap.createBitmap(src, 0, 0, src.getWidth(), src.getHeight(), matrix, true);
      return bmOut;

      }
          }