Bitmap旋转方法

最近在做一个ORC图片解析的功能，要求解析出数字

但是发现他解析只能解析横着的图片，然后我拍照的时候拍的是竖直照片，当然你也可以去旋转照相机的屏幕

但是我这里为了方便选择的是竖直拍出来

然后，旋转下咯（ps:网上找的通用方法）

方法1. 利用Bitmap.createBitmap

   Bitmap
adjustPhotoRotation(Bitmap bm, final int orientationDegree)
{

            Matrix m = new Matrix();
             m.setRotate(orientationDegree, (float) bm.getWidth() / 2, (float) bm.getHeight() / 2);

             try {

           Bitmap bm1 = Bitmap.createBitmap(bm, 0, 0, bm.getWidth(), bm.getHeight(), m, true);

               return bm1;

              } catch (OutOfMemoryError ex) {
                     }

               return null;

}

方法2. 利用Canvas.drawBitmap

Bitmap
adjustPhotoRotation(Bitmap bm, final int orientationDegree)
{

         Matrix m = new Matrix();
         m.setRotate(orientationDegree, (float) bm.getWidth() / 2, (float) bm.getHeight() / 2);
         float targetX, targetY;
         if (orientationDegree == 90) {
         targetX = bm.getHeight();
         targetY = 0;
         } else {
         targetX = bm.getHeight();
         targetY = bm.getWidth();
   }

     final float[] values = new float[9];
     m.getValues(values);

     float x1 = values[Matrix.MTRANS_X];
     float y1 = values[Matrix.MTRANS_Y];

     m.postTranslate(targetX - x1, targetY - y1);

     Bitmap bm1 = Bitmap.createBitmap(bm.getHeight(), bm.getWidth(), Bitmap.Config.ARGB_8888);

Paint paint = new Paint();
     Canvas canvas = new Canvas(bm1);
     canvas.drawBitmap(bm, m, paint);

     return bm1;
   }

其中方法2的耗时是方法一的一半~

建议是方法二