本文算法是将24 位真彩图的亮度分量分块

DCT ,然后利用DCT 量化系数的奇偶特性嵌入8

位灰度水印图,并通过PN 序列加密来保证水印的

安全性。算法中,将灰度图像转换为二进制数据

流,置乱后扩频调制,隐藏在宿主DCT 系数量化值

中,提取时不需要宿主信号,实现水印信号的盲提

取。-This algorithm is 24-bit true color pictures of the luminance component of block DCT, quantization DCT coefficients and then use the parity properties of 8-bit grayscale watermark embedding map, and through the PN sequence of encryption to ensure the security of the watermark. Algorithm, the gray image into binary data stream, scrambling after the spread spectrum modulation, hidden in the host DCT coefficient quantization values, the extraction does not require the host signal, the blind watermark extraction.