怎么知道视频是横着录像的， 还是竖着录像的。

/**
     * 获得本地视频的预览图
     * 
     * @param videoPath
     * @return
     */
    public static Bitmap obtainVideoThumbnail(String videoPath) {
        MediaMetadataRetriever media = new MediaMetadataRetriever();
        media.setDataSource(videoPath);
        Bitmap bitmap = media.getFrameAtTime();
        Matrix matrix = new Matrix();
        matrix.postScale(0.1f, 0.1f); // 长和宽放大缩小的比例
        Bitmap resizeBmp = Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(), matrix, true);
        Log.d("h_bl", resizeBmp.getWidth() + "  X  " + bitmap.getHeight());
        bitmap.recycle();
        return resizeBmp;
    }

ratio = ((float) vInfo.getVideoThumbnail().getWidth()) / ((float) vInfo.getVideoThumbnail().getHeight());
        Log.d(TAG, "ratio=" + ratio);