经过置乱变换的水印再用混沌技术进行加密,在密钥未知的前提下,非授权者无法获取嵌入的数字水印,从而提高了水印系统的安全性-After scrambling transformation chaotic watermarking technology and then encrypted in the key premise of the unknown, unauthorized persons can not obtain the embedded watermark, so as to enh