BitmapFactory.Options

Question

最近，我正在学习如何基于android Android Training在android中有效地加载位图。我遇到了一个问题。这是我的代码：

    BitmapFactory.Options options = new BitmapFactory.Options();
    options.inJustDecodeBounds = true;
    BitmapFactory.decodeResource(getResources(), R.drawable.f, options);
    Log.i("TOM", "resource bitmap dimension: " + options.outWidth + " X " + options.outHeight);

    options.inSampleSize = 8;
    options.inJustDecodeBounds = false;
    Bitmap bm = BitmapFactory.decodeResource(getResources(), R.drawable.f, options);
    Log.i("TOM", "require bitmap dimension: " + options.outWidth + " X " + options.outHeight);

这些代码打印：

resource bitmap dimension: 1365 X 2048
require bitmap dimension: 342 X 512

我将inSampleSize设置为8后，width和height成为原始维度的1/8，Android Training表示。但512是1/4的{​​{1}}！ 为什么呢？