一种基于伪随机序列和DCT的遥感影像水印算法
An Algorithm for Digital Watermark Based on Pseudo-Random Sequence and DCT for Remote Sensing Image
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摘要: 首先,对原始影像进行分块,通过伪随机序列选择要嵌入的影像块;然后,采用量化的方法在每一块的DCT低频系数中嵌入水印信息;最后,通过精度约束,对嵌入水印信息后的遥感影像进行误差控制。由于采用了量化的方法嵌入水印信息,其提取过程不需要原始影像的参与,实现了盲检测。实验结果表明,该算法在满足水印算法鲁棒性的同时,也能达到对遥感影像近乎零修改的目标。Abstract: According to the basic requirements of digital watermark for remote sensing image,an algorithm for digital watermark based on pseudo-random sequence and DCT for remote sensing image was proposed.Firstly,the original image was segmented,and the image blocks were selected by the pseudo-random sequence.Then,the low frequency coefficients after DCT were got,and the watermark information was embedded in the low frequency coefficients of each image block using the quantitative method.Finally,the errors of embedded image were controlled by the accuracy constraints.Because the watermark information embedded was done with quantitative method,the watermarked image authentication needed no information about the original image.This algorithm realized blind extraction of digital watermarking.The experimental results show that the proposed algorithm the robustness and achieve near-zero change of remote sensing image.