bis = new BufferedInputStream(i, 1024 * 4);
            out = new ByteArrayOutputStream();
            int len = 0;
            while ((len = bis.read(isBuffer)) != -1) {
                out.write(isBuffer, 0, len);
            }
            out.close();
            bis.close();
        } catch (MalformedURLException e1) {
            e1.printStackTrace();
            return null;
        } catch (IOException e) {
            e.printStackTrace();
        }
        if (out == null)
            return null;
        byte[] data = out.toByteArray();
        BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeByteArray(data, 0, data.length, options);
        options.inJustDecodeBounds = false;
        int be = (int) (options.outHeight / (float) sc);
        if (be <= 0) {
            be = 1;
        } else if (be > 3) {
            be = 3;
        }
        options.inSampleSize = be;
        Bitmap bmp = null;
        try {
            bmp = BitmapFactory.decodeByteArray(data, 0, data.length, options); // 返回縮略圖
        } catch (OutOfMemoryError e) {
            // TODO: handle exception
            System.gc();
            bmp = null;
        }
        return bmp;
    }