Android - how to scale a bitmap and retain the original's quality

public static Bitmap scaleBitmap(Bitmap bitmap, int newWidth, int newHeight)
{
  Bitmap scaledBitmap = Bitmap.createBitmap(newWidth, newHeight, Config.ARGB_8888);

  float scaleX = newWidth / (float) bitmap.getWidth();
  float scaleY = newHeight / (float) bitmap.getHeight();
  float pivotX = 0;
  float pivotY = 0;

  Matrix scaleMatrix = new Matrix();
  scaleMatrix.setScale(scaleX, scaleY, pivotX, pivotY);

  Canvas canvas = new Canvas(scaledBitmap);
  canvas.setMatrix(scaleMatrix);
  canvas.drawBitmap(bitmap, 0, 0, new Paint(Paint.FILTER_BITMAP_FLAG));

  return scaledBitmap;
}