将水印加在低频区域可以具有较好的鲁棒性 将水印加在高频区域可以获得较好的透明性, 但鲁 棒性差 将水印加在中频区是一种鲁棒性与透明性 的折中方案。-watermark added to the low-frequency region can have good watermark robustness added to the high frequency region can be made good through Ming, but the poor robust wate